This thesis describes a three year study which explored perceptions and experiences of being involved in self care and perceptions of control and self-efficacy over time amongst patients receiving a six month course of chemotherapy treatment for colorectal cancer. The study was underpinned by Leventhal’s Self Regulation Model and aimed to explore how patients undergoing chemotherapy for colorectal cancer perceived the meaning of self care, what they did as part of their self care in managing the effects of their treatment and whether this changed between the beginning and end of their six month course of chemotherapy. The study also set out to explore the relationship between patients’ perceptions of control and self efficacy and their involvement in self care. The study adopted a patient focussed, mixed method, longitudinal approach for complementarity and expansion purposes in which the qualitative findings formed the focus of the investigation, supplemented by the quantitative findings. This was important to provide a greater breadth and range to the study and to obtain a realistic understanding of patients’ perceptions and experiences of being involved in self care during their six month course of chemotherapy treatment and the influence of their perceptions of control and self efficacy on their involvement in self care. Thirty one patients participated in the study and data were collected using qualitative semi structured interviews (with a subsample of patients who participated in the study) and quantitative questionnaires (Illness Perception Questionnaire-revised and the Strategies Used by People to Promote Health) and prospective self care diaries with the full study sample. Data were collected at several time points over the course of patients’ chemotherapy treatment (beginning, middle and end of treatment) and were analysed and integrated in accordance with Tashakkori and Teddlie (1998)’s guidance for integrating qualitative and quantitative findings in a mixed methods study. The study findings revealed that the use of a mixed method, longitudinal study design was a valuable approach for understanding patients’ involvement in self care during chemotherapy for colorectal cancer and the influence of factors, such as their perceptions of control, on their subsequent involvement in their self care. In particular, the principal findings suggested that self care held a range of meanings to the patients in this study. Principally, patients’ self care consisted of two components; physical self care, carried out to manage the physical impact of undergoing treatment, and emotional self care, carried out to manage their emotional response to being diagnosed with, and undergoing treatment for, cancer. The findings suggested that there was no association between patients’ perceptions of control and the degree of self care that they carried out identified in the quantitative analysis. However, in the qualitative analysis, it was revealed that patients’ perceptions of control were likely to influence their attitudes towards their active involvement in self care and the importance with which they viewed this role. In particular, patients who considered themselves to have a high degree of control during their treatment were more likely to believe that they could limit the impact of the treatment through their own actions, that being actively involved in their self care was important and were interested in taking on this role, and that they would use a greater range of self care strategies in helping to manage the impact of their treatment. Conversely patients who considered themselves to have a lower degree of control during their treatment were less likely to believe that they could limit the impact of the treatment through their own actions, that their active involvement in self care was important and were less likely to expect to take on an active role, preferring to leave the management of treatment-related effects to health professionals, whom they regarded as being the “experts”. The findings from this study have implications for nursing practice because they reinforce the importance of the listening to the patient’s experience and how this approach can contribute to a fuller and more accurate understanding of how patients become involved in their self care and the factors that influence this. This is important so that nurses can provide holistic care, tailored to meet their patients’ self care needs and preferences, and to encourage partnership working between patients, nurses, allied health professionals and other agencies in promoting involvement in self care. The findings also have implications for theories relating to self care in emphasising the importance of patient centred models of care and for Leventhal’s Self Regulation Model in adding further support for the components of the model yet also offering a greater understanding of how the model fits with patients’ emotional responses to the effects of illness and its’ treatments. Finally, the study findings have implications for future research, calling for further research to focus on the meaning of constructs such as self care and control from the patients’ perspective and to further explore the use of the mixed methodology in researching and understanding patients’ involvement in self care and the factors that influence this.

The most common form of childhood cancer is Acute Lymphoblastic Leukemia (ALL). Patients treated for ALL may experience short- and long-term physiological and cognitive effects due to treatment. However, delayed emotional and behavioral effects in pediatric survivors, as well as risk-factors that may make them more susceptible to developing problems with psychological and behavioral functioning are less understood. Studies investigating pediatric survivors have demonstrated that negative emotional and behavioral late effects can and do occur (Hobbie et al., 2000; Buizer et al. 2006; Novakovic et al., 1996; Mulhern, Wasserman, Friedman, & Fairclough, 1989), and it has been purported that survivors experience higher rates of depression, anxiety and low self-esteem (Koocher, O’Malley, Gogan, & Foster, 1980; Kazak, 1994). Anxiety in particular, has been identified as one of the longest lasting psychological sequelae of cancer (Kazak, 1994). Still, the data on long-term psychological sequelae is mixed, with some studies suggesting healthy, long-term, psychological adjustment (Brown et al., 1992; Fritz, Williams & Amylon, 1988; Greenberg, Kazak, & Meadows, 1989). This pilot study attempted to investigate emotional and behavioral late effects of cancer as reported by survivors and their caregivers on the Behavior Assessment System for Children, Second Edition (BASC-2). This study also investigated potential risk factors that made it more likely to develop emotional and behavioral late-effects. This study hypothesized that females, those undergoing high intensity chemotherapy, and those starting chemotherapy at an earlier age, would report significantly more internalizing and externalizing problems. Analysis revealed significant differences in reporting of anxiety, depression, attention and hyperactivity symptoms combined based on the age when treatment started. No other significant findings were uncovered; however, in an effort to provide directions for future research, patterns in the data were examined by comparing overall means on BASC-2 subscales. For example, females reported more hyperactive symptoms than males. In general, individuals who started treatment at younger ages reported more difficulty with emotional and behavioral functioning. Additionally, males and females adaptive behavior fell within normal limits. Overall, no BASC-2 mean scores were in the at-risk or clinically significant range of impairment suggesting adequate emotional, behavioral and adaptive functioning overall. / text

published_or_final_version / abstract / toc / Community Medicine / Doctoral / Doctor of Philosophy

Purpose: Control of micrometastatic ovarian cancer in the peritoneal cavity remains a major objective in post-surgical treatment. The purpose of this project was to investigate the efficacy and toxicity of targeted alpha therapy (TAT) for ovarian cancer in vitro and in vivo in animal models and to select the optimal targeting vector for an ovarian cancer clinical trial. Animal models of ovarian, breast and prostate cancer were developed and for further TAT; a phase I melanoma clinical trial was supported, paving the way for an ovarian cancer clinical trial. Methods: The expression of the turnor-associated antigens (Her2, MUC1, uPAfuPAR) on cancer cell line, animal model xenografts and human ovarian cancer tissue was tested by immunostaining. MTS and TUNEL assays were used to evaluate cell killing of alpha conjugates in monolayer and spheroids. Toxicity and maximum tolerance doses for different vectors were tested and determined in vivo. Pharmacokinetics was studied for different time points and different parameters. The antiproliferative effect of 213Bi-C595 and 213Bi-PAI2 was tested at 9 days post-peritoneal cell inoculation of the ovarian cancer cell line OVCAR3. The treatment efficacy of 213Bi-Herceptin was tested at a 2 days post-subcutaneous breast cancer cell BT474 inoculation. Mice were injected (i.p) with various concentrations of alpha conjugates (AC). Changes in cancer progression were assessed by girth size and tumor size. Results: uPA/uPAR and MUCI are expressed on ovarian cancer cell lines and more than 45% ovarian cancer tissue, while HER2 was only positive in one cell line and was positive in less than 15% of ovarian cancer tissues. The ACs can target and kill cancer cells in vitro in a dose dependent fashion. TUNEL positive cells were found after incubation with the different ACs. PAI2 and C595 vectors were selected for in vivo ascites model study of OVCARJ cell with high expression. Delayed and acute toxicity in animal models showed that radiation nephropathy was the cause of body weight loss. Biodistribution studies showed that kidney was the major uptake organ. L-lysine can reduce kidney uptake for 213Bi-PAI2, but no significant differences were found. A single ip injection of 213Bi-C595 or 213Bi-PAI2 can inhibit ascites growth, whereas, 213Bi-Herceptin can inhibit breast cancer growth in a nude mice model. Conclusion: 213Bi labelled targeting vectors can specifically target ovarian cancer cells in vitro and inhibit tumor growth in vivo. These ACs may be useful agents for the treatment of ovarian cancer at the minimum residual disease stage.

[Truncated abstract] Therapeutic Radiation has been used for the treatment of cancer and other diseases for nearly a century. Over the past 20 years, Hyperbaric Oxygen Treatment (HBOT) has been used to assist wound healing in the prevention and treatment of the more severe complications associated with the side effects of Therapeutic Radiation Treatment (TRT). The use of HBOT is based on the premise that increased oxygen tissue tension aids wound healing by increasing the hypoxic gradient and stimulating angiogenesis and fibroblast differentiation. As it takes up to 6 months for a hypoxic state to develop in treated tissue, following radiation treatment, current recommendations for HBOT state that it is not effective until after this time. During this 6 month period, immediately following TRT, many specialized tissues in or adjacent to the field of irradiation, such as salivary glands and bone, are damaged due to a progressive thickening of arteries and fibrosis, and these tissues are never replaced. Currently, HBOT is used to treat the complications of TRT, but it would be far better if they could be prevented . . . In summary, this experimental model has fulfilled its prime objective of demonstrating that HBOT is effective in reducing the long-term side effects of therapeutic radiation treatment in normal tissue, when given one week after the completion of the radiation treatment and statistically disproves the Null Hypothesis that there is no difference in the incidence of postoperative complications or morbidity of TRT when 20 intermittent daily HBOT are started one week after completion of TRT. This project provides an extensive description of the histological process and also proposes a hypothesis for the molecular events that may be taking place.

Η παρούσα διατριβή αναφέρεται στην ανάπτυξη νέων πεπτιδικών αναλόγων μπομπεσίνης (ΒΝ) με απώτερο στόχο την ενδεχόμενη κλινική εφαρμογή τους στο πεδίο της διαγνωστικής ογκολογίας με SPECT (Υπολογιστική Τομογραφία Εκπομπής ενός Φωτονίου, Single-photon emission computed tomography) και PET (Τομογραφία Εκπομπής Ποζιτρονίων, Positron emission tomography). Η ΒΝ αποτελεί έναν εξειδικευμένο πεπτίδιο-προσδέτη για τους υποδοχείς του πεπτιδίου απελευθέρωσης της γαστρίνης (gastrin-releasing peptide receptors, GRPrs), οι οποίοι υπερεκφράζονται στην επιφάνεια διαφόρων τύπων καρκινικών κυττάρων. Οι υποδοχείς GRP δυνητικά θα μπορούσαν να θεωρηθούν ιδανικός στόχος για την απεικόνιση νευροενδοκρινικών όγκων μετά από χορήγηση ραδιοεπισημασμένων παραγώγων ΒΝ, με τεχνικές μοριακής διαγνωστικής, αλλά και για την στοχευμένη θεραπευτική αντιμετώπιση του καρκίνου. Με αυτό τον στόχο σχεδιάστηκαν και συντέθηκαν πεπτιδικά ανάλογα ΒΝ για τα οποία πραγματοποιήθηκε μία σειρά προκλινικών μελετών με σκοπό τη διαμόρφωση και την εφαρμογή ενός πλαισίου διάκρισης των κατάλληλων ραδιοχημικών και ραδιοφαρμακολογικών χαρακτηριστικών τα οποία θα μπορούσαν να οδηγήσουν ένα από αυτά τα υποψήφια διαγνωστικά σκευάσματα του σε κλινικές μελέτες ανίχνευσης του καρκίνου. Μέθοδος: Στα πλαίσια της παρούσας διατριβής σχεδιάστηκαν και συντέθηκαν πεπτιδικά ανάλογα BN, κατάλληλα για επισήμανση με ραδιονουκλίδια, με την παρακάτω γενική δομή: Υ-Χ-ΒΝ(2-14) όπου Υ = ο χηλικός παράγοντας για τη σύμπλεξη του ραδιομετάλλου, Χ = η συνδετική ομάδα και ΒΝ(2-14) το φαρμακοφόρο τμήμα. (a) Προκειμένου να απεικονισθούν όγκοι με SPECT όπου: Υ = [GlyGlyCys-] για τη σύμπλεξη με το 99mTc και το 185/187Re (μη ραδιενεργό), Χ = -(αργινίνη)3-, (BN-A), ή -(ορνιθίνη)3-, (BN-O). (b) Ενώ για τη μοριακή απεικόνιση όγκων με την τεχνική PET, όπου Υ = [c-carboxylic acid-cyclam] για σύμπλεξη με 64Cu, και Χ = -(ορνιθίνη)3-, (BN-C). Σε όλες τις παραπάνω περιπτώσεις χρησιμοποιήθηκε το τμήμα της φυσικής αλληλουχίας του πεπτιδίου μπομπεσίνη, από το 2o εως το 14ο αμινοξύ, σε συνδυασμό με αμινοξική, θετικά φορτισμένη, συνδετική ομάδα (spacer). Τα παραπάνω παράγωγα και τα αντίστοιχα σύμπλοκα τους με τα μέταλλα αρχικά αξιολογήθηκαν χημικά και ραδιοχημικά με διάφορες αναλυτικές μεθόδους. Ακολούθησε η ραδιοφαρμακολογική αξιολόγηση τους με τις παρακάτω in vitro δοκιμασίες: (a) μελέτη σταθερότητας σε δείγματα αίματος, (b) προσδιορισμός της συγγένειας τους με τον GRPr (υπολογισμός τιμών IC50) και (c) του ρυθμού εσωτερικοποίησης/εξωτερικοποίησης σε κύτταρα PC-3 (ανθρώπινου καρκίνου προστάτη). Στη συνέχεια πραγματοποιήθηκαν μελέτες in vivo (βιοκατανομή, απεικόνιση με γ-κάμερα), σε φυσιολογικά ζωικά πειραματικά πρότυπα (ποντίκια, αρουραίους και κουνέλια) και σε πειραματικά πρότυπα καρκίνου (ποντίκια SCID, με όγκους από κύτταρα PC-3). Επιπλέον με βάση τα in vivo αποτελέσματα διεξάχθηκε η φαρμακοκινητική αξιολόγηση τους και ο συσχετισμός μεταξύ δομικών και φαρμακοκινητικών χαρακτηριστικών. Τέλος επιχειρήθηκε η αλλομετρική κλιμάκωση των φαρμακοκινητικών αποτελεσμάτων από τα διάφορα είδη πειραματοζώων στον άνθρωπο. Αποτελέσματα: Για τα παράγωγα τα οποία συντέθηκαν για σύμπλεξη με 99mTc προκειμένου να απεικονισθούν όγκοι με SPECT, παρατηρήθηκαν τα εξής: Τα BN-A και BN-O συμπλέχθηκαν αποτελεσματικά με το 99mTc (απόδοση > 98%), αλλά και το χημικά όμοιο του ρήνιο (μη ραδιενεργό). Κατά τις μελέτες σταθερότητας το παράγωγο 99mTc-BN-O αποδείχθηκε σταθερότερο του 99mTc-BN-Α, (π.χ. πλάσμα του ποντικού σε 5 min επώασης το % άθικτο πεπτίδιο ήταν 44.28 και 42.48, ενώ στο ανθρώπινο πλάσμα σε 1 ώρα επώασης ήταν 63.05 και 60.2 αντίστοιχα). Η συγγένεια πρόσδεσης στον GRPr των παραπάνω παραγώγων, αλλά και των συμπλόκων τους με το μη ραδιενεργό Re, τα οποία προσομοιάζουν τα αντίστοιχα ραδιενεργά σύμπλοκα τους με το 99mTc (IC50, BN-Α, 0.5 ± 0.09, 185/187Re-BN-A, 1.58 ± 0.16, BN-Ο, 0.46 ± 0.04, 185/187Re-BN-Ο, 0.77 ± 0.07 nM), ήταν κοντά στο πρότυπο [Tyr4]-BN (0.45 ± 0.04 nM). Το συνολικό ποσοστό εσωτερικοποίησης των παραπάνω συμπλόκων 99mTc-BN-Α και 99mTc-BN-Ο στα κύτταρα PC-3 ήταν παρόμοιο (~25%), αλλά ο ρυθμός εσωτερικοποίησης τους διέφερε, καθώς χρειάστηκαν 120 min και 60 min για φτάσουν τη μέγιστη τιμή εσωτερικοποίησης αντίστοιχα. Ο ρυθμός εξωτερίκευσης ήταν ο ίδιος. Μετά από 90 min επώασης το ~ 70% της αρχικής ποσότητας πεπτιδίου παραμένει εγκλωβισμένο στα κύτταρα. Από τις μελέτες βιοκατανομής και φαρμακοκινητικής του 99mTc-BN–A και του 99mTc-BN–Ο σε φυσιολογικά ποντίκια φάνηκε ότι και τα δύο ραδιοπεπτίδια απομακρύνονται γρήγορα από το αίμα, καθώς μικρό ποσοστό της χορηγούμενης δόσης (ID)/g (2.61 και 2.76 % αντίστοιχα) παραμένει 30 min μετά τη χορήγηση (p.i.). Η βασική οδός απομάκρυνσης τους από τον οργανισμό ήταν το ουροποιητικό σύστημα καθώς μεγάλο ποσοστό των ραδιοπεπτιδίων εντοπίστηκε στα ούρα 1 h p.i. (64.16 και 56.33 % ID αντίστοιχα). Το γεγονός αυτό συσχετίσθηκε με την παρουσία της θετικά φορτισμένης συνδετικής ομάδας. Η νεφρική απέκκριση επιδιώκεται έναντι της ηπατοχολικής, γιατί με αυτόν τον τρόπο μειώνεται η συσσώρευση της ραδιενέργειας στην άνω κοιλιακή χώρα και διευκολύνεται η εντόπιση όγκων στην περιοχή αυτή. Το 99mTc-BN–A απομακρύνεται ταχύτερα από το αίμα από τα νεφρά και γενικότερα από τον οργανισμό από ότι το 99mTc-BN–Ο, αλλά εμφανίζει μεγαλύτερη συσσώρευση στο ήπαρ (4.43 ± 1.04 και 0.99 ± 0.20 %ID/g, 60 min p.i. αντίστοιχα). Από τις μελέτες βιοκατανομής και απεικόνισης με γ-κάμερα σε ποντίκια SCID με όγκους PC-3 το παράγωγο 99mTc-BN–A εντόπισε αποτελεσματικά τον όγκο. Μετά από πειράματα συγχορήγησης φυσικής ΒΝ παρατηρήθηκε μείωση του ραδιοεπισημασμένου παραγώγου στον όγκο και στο πάγκρεας, τα σημεία στα οποία εντοπίζονται υποδοχείς GRPrs, επιβεβαιώνοντας έτσι την ειδική δέσμευση του ραδιοεπισημασμένου παραγώγου σε αυτούς. Συγκρίνοντας τα παραπάνω αποτελέσματα με το 99mTc-BN–Ο διαπιστώθηκαν καλύτεροι λόγοι διάκρισης από το 99mTc-BN–A στους διάφορους χρόνους μελέτης (π.χ. 60 min p.i. ήταν όγκος/αίμα, 6.67 έναντι 3.62, όγκος/μύες, 14.0 έναντι 5.60, όγκος/ήπαρ, 2.9 έναντι 0.82, αντίστοιχα). Εξαιτίας όλων των παραπάνω αποτελεσμάτων το παράγωγο 99mTc-BN-Ο επιλέχθηκε για περαιτέρω μελέτη. Για το 99mTc-BN-Ο πραγματοποιήθηκαν περαιτέρω in vitro μελέτες σταθερότητας σε πλάσμα αίματος αρουραίων και κουνελιών και in vivo μελέτες βιοκατανομής (απεικόνισης σε γ-καμερα). Παράλληλα πραγματοποιήθηκε και η φαρμακοκινητική ανάλυση των δεδομένων. Επιπλέον επιχειρήθηκε να αντιμετωπισθεί το πρόβλημα της νεφρικής συσσώρευσης του 99mTc-BN-Ο στα νεφρά με τη συγχορήγηση Gelofusine (Gelo). Από τη συγχορήγηση Gelo στα φυσιολογικά (ποντίκια, αρουραίοι) και καρκινικά πειραματικά πρότυπα (ποντίκια SCID με όγκους PC-3) παρατηρήθηκαν ταχύτερη κάθαρση του αίματος και αποβολής από τα νεφρά. Τέλος πραγματοποιήθηκε πρωτότυπη μελέτη αλλομετρικής κλιμάκωση των φαρμακοκινητικών αποτελεσμάτων του 99mTc-BN-Ο με στόχο την πρόβλεψη της συμπεριφοράς του καθώς της συμπεριφοράς παρόμοιων μορίων στον άνθρωπο κατά τη διεξαγωγή κλινικών μελετών. Εξαιτίας των παραπάνω θετικών αποτελεσμάτων αναφορικά με το τμήμα Η2Ν-(ορνιθίνη)3-ΒΝ(2-14) και προκειμένου να επιτευχθεί η βελτιστοποίηση της ικανότητα σύμπλεξής του με ιόντα χαλκού (π.χ. 64Cu για διάγνωση με PET) συνδέθηκε ομοιοπολικά με αυτό ένας νέος χηλικός παράγοντα το c-carboxylic acid cyclam. Από την ομοιοπολική σύζευξη των παραπάνω προέκυψε ένας νέο ανάλογο ΒΝ, το ΒΝ-C. Με τη χρήση διαφόρων αναλυτικών τεχνικών (IR, UV-Vis, ESI-MS, ESR, κρυσταλλογραφία ακτίνων Χ) διαπιστώθηκε ότι τόσο ο c-carboxylic acid cyclam όσο και ΒΝ-C, ο τελικός πεπτιδικός προσδέτης, έχουν την ικανότητα σύμπλεξης με CuII. Το πεπτιδικό παράγωγο BN-C και το σύμπλοκο του με το χαλκό, Cu-BN-C. δοκιμάσθηκαν ως προς τη συγγένεια δέσμευσης τους με τον GRPr σε κυτταρικές καλλιέργειες PC-3 όπου και παρουσίαζαν συγγένεια (IC50 = 0.3 ± 0.03 και 0.33 ± 0.03 nM, αντίστοιχα) παρόμοια με το πρότυπο πεπτίδιο προσδέτη [Tyr4]-BN (0.45 ± 0.04 nM). Συμπέρασμα: Οι παραπάνω μελέτες οριοθετούν ένα γενικότερο πλαίσιο προκλινικού προσδιορισμού εκείνων των ραδιοχημικών και ραδιοφαρμακολογικών in vitro και in vivo ιδιοτήτων, οι οποίες θα μπορούσαν να οδηγήσουν ένα παράγωγο ΒΝ σε περαιτέρω κλινικές μελέτες. Με βάση τα παραπάνω επιλέχθηκε και αναπτύχθηκε ένα πεπτιδικό ανάλογο ΒΝ, το οποίο σε κάθε περίπτωση αποδείχθηκε ότι διαθέτει τον κατάλληλο συνδυασμό των παραπάνω χαρακτηριστικών για περαιτέρω ανάπτυξη ως ραδιοδιαγνωστικό σκεύασμα για SPECT (BN-O) και PET (ΒΝ-C) σε κλινικό επίπεδο. Επιπλέον η φαρμακοκινητική ανάλυση και η αλλομετρική κλιμάκωση των παραπάνω αποτελεσμάτων συνεισφέρουν σημαντικά στην αύξηση της πιθανότητας μελλοντικής κλινικής εφαρμογής των παραπάνω παραγώγων στον άνθρωπο. / The present Thesis refers to the development of new peptidic bombesin (BN) analogs for application in the field of tumor diagnosis with the SPECT (Single-photon emission computed tomography) and PET (Positron emission tomography) techniques. The BN peptide is a specific ligand for the gastrin-releasing peptide receptors (GRPrs), which are over-expressed on the surface of various types of tumor cells. GRPrs can be considered as an ideal target for radiolabeled BN analogues in the molecular diagnosis of neuro-endocrine tumors as well as in the targeted treatment of cancer. Taking the above into consideration, three BN analogues were designed and synthesized as potential molecular diagnostics of tumors. Thus, a series of preclinical studies were conducted in order to find out the best candidate for further development in clinical studies. Methods: All the BN analogues of the present study can be described by the following general structure: Υ-Χ-ΒΝ(2-14) Where Y = the chelator group for the radionuclide, X = a spacer group and BN(2-14) = the pharmacophore group. (a) For the diagnosis of tumors with SPECT: Υ = [GlyGlyCys-], suitable for the complexation of 99mTc and 185/187Re and X= -(arginine)3-, (BN-A), or -(ornithine)3-, (BN-O). (b) Further on, for tumor diagnosis with PET: Υ = [c-carboxylic acid-cyclam] suitable for the complexation of 64Cu, και Χ = -(ornithine)3-, (BN-C). For all the above cases the part from the 2nd to the 14th amino acid of the naturally occurring BN was used, in combination with a spacer group composed of three positively charged amino acids. The amino acids were either naturally occurring (arginine) or not (ornithine). The above BN analogues as well as their metal complexes were chemically and radiochemically analyzed and evaluated in vitro. The in vitro evaluation of the BN derivatives included assays for the determination of (a) their stability in blood samples, (b) their affinity for the GRPrs (by the calculation of their IC50 values), (c) as well as of their internalization and externalization rates in PC-3 cell (human prostate cancer cell line) cultures. Additionally a series of in vivo assays were conducted including: biodistibution studies in normal (mice, rats, rabbits) and in experimental cancer animal models (SCID mice with PC3 tumors). For the later in addition to the biodistribution tumor imaging studies were carried out using an experimental small animal gamma camera. Based on the results of the in vivo studies, a series of pharmacokinetic analyses were performed and the results were correlated with the structural characteristics of the BN analogues. Finally, the results from the pharmacokinetic analyses of the three different animal species, (mouse, rat, rabbit) were combined and scaled up for a human of 70 Kg, by using the allometric approach. Results: The BN analogues BN-A and BN-O, which were designed for application in tumor imaging with SPECT, were able to form stable complexes with 99mTc (in high yield > 98%), as well as with Re (non radioactive). The two elements 99mTc and Re belong to the same group of the Periodic Table of elements and thus they are considered to have similar chemical properties. During the in vitro stability assays 99mTc-BN-O prove to be more stable than the 99mTc-BN-Α i.e. the % percentages of intact peptide for mouse plasma (after 5 min incubation) were 44.28 and 42.48 %, while for human plasma the percentages of intact peptide (after 1h of incubation) were 63.05 and 60.2 respectively. The affinities (IC50 values) of BN-Α (0.5 ± 0.09 nM), and BN-Ο (0.46 ± 0.04 nM), as well as of their non radioactive complexes with Rhenium 185/187Re-BN-A, 1(.58 ± 0.16 nM) and 185/187Re-BN-Ο (0.77 ± 0.07 nM) were similar to the one of the control peptide [Tyr4]-BN (0.45 ± 0.04 nM). Although the total amount of internalized radiolabeled peptide was the same for both 99mTc-BN-Α and 99mTc-BN-O (~25%), their rates of internalization differed. The ornithine-spacer analogue, 99mTc-BN-O, internalized a lot faster (60 min for maximum internalization plateau) than the arginine-spacer analogue, 99mTc-BN-Α (120 min for maximum internalization plateau). The externalization rates for both analogues were the same, with ~ 70% of the initially internalized radiolabeled peptide remaining inside the cells even after 90 min of incubation. From the biodistribution and pharmacokinetic studies of 99mTc-BN–A and 99mTc-BN–Ο a fast blood clearance was observed for both peptides, with small amounts of the initial dose remaining in the blood stream 30 min p.i. (2.61 and 2.76 % ID/g, respectively). The main clearance route throughout the body in both cases was the urinary system and high percentages of the radiolabeled peptides were detected in the urine 1 h p.i (64.16 and 56.33 % ID respectively). The latter was related to the presence of the positively charged spacer group. A clearance through the urinary system is preferred instead of the hepatobiliary system since in that way the decrease of the upper abdominal region background radiation is achieved. Although the arginine-spacer analogue 99mTc-BN–A was cleared from the kidneys and the body with higher rates than 99mTc-BN–Ο, it showed a higher liver accumulation than the latter (4.43 ± 1.04 and 0.99 ± 0.20 %ID/g, 60 min p.i. respectively). Both in the biodistribution and in the gamma-camera tumor-imaging studies the BN analogue 99mTc-BN–A was able to efficiently locate the tumour. During the GRPrs blocking studies the amount of 99mTc-BN–A was reduced both in the tumour and in the pancreas, where the GRPrs are located, proving thus the specific binding of 99mTc-BN–A to those receptors. Comparing the tumor/normal tissue contrast ratios between 99mTc-BN–Ο and 99mTc-BN–A the ornithine spacer analogue proved a better choice since it presented greater values (i.e. 60 min p.i. tumor/blood, 6.67 vs 3.62, tumor/muscle, 14.0 vs 5.60, tumor/liver, 2.9 vs 0.82, respectively). According to all the above results 99mTc-BN-Ο was selected between the two SPECT tumor imaging agent candidates for further studies. For 99mTc-BN-Ο additional in vitro stability assays were conducted in rats and rabbits plasma, which were followed by in vivo biodistribution studies in normal rats and imaging studies in normal rabbits. The in vivo data were analyzed with the appropriate pharmacokinetic approaches. In an effort to achieve a faster clearance of 99mTc-BN-Ο from the kidneys a new approach was tested by its co-injection with Gelofusine (Gelo). During the Gelo co-injection studies in normal mice, in rats as well as in SCID mice with PC-3 tumors a faster renal clearance was observed. Finally by combining the in vivo results of 99mTc-BN-Ο from the three different animal species (mice, rats, rabbits) the allometric scale up of the pharmacokinetic parameters was achieved and the prediction of those parameters for a man of 70 kg. The results of latter study could probably be extended to predict the pharmacokinetic profile of other similar molecules in the preclinical stage of development. Due to promising results of obtained from the BN analogue with the ornithine spacer, Η2Ν-(ornithine)3-ΒΝ(2-14), and in order to improve its ability to form complexes with copper radionuclides i.e. 64Cu, which are suitable for PET imaging, a new chelator group was introduced into the peptide sequence. The chelator group c-carboxylic acid cyclam was covalently attached to the peptide chain Η2Ν-(ornithine)3-ΒΝ(2-14) to give a new bombesin analogue ΒΝ-C. The chelator group and the new BN analogue were able to form complexes with cold copper fast and under mild conditions. The copper complexes of the above molecules were analyzed with a variety of techniques like IR, UV-Vis, ESI-MS, ESR, X ray crystallography. Additionally both the BN analogue BN-C and its complex with copper Cu-BN-C were tested for their affinity for GRPrs in PC-3 cell lines, where it was found that their IC50 values of both were similar (IC50 = 0.3 ± 0.03 και 0.33 ± 0.03 nM, respectively) to the control peptide [Tyr4]-BN (0.45 ± 0.04 nM). Conclusion: The above studies can be considered the essential parts of a discrimination process of the ideal radiochemical and radiopharmacological characteristics, which could lead a BN analogue to clinical trials. According to the results of the above preclinical studies a suitable BN analogue was selected for further clinical development as a tumor imaging agent with SPECT (BN-O) as well as PET (ΒΝ-C). Additionally the pharmacokinetic analysis in three different animal species and allometric scale up of those parameters for the human will enhance the probability of its further application in clinical trials.

Thesis (MNutr (Interdisciplinary Health Sciences. Human Nutrition))--Stellenbosch University, 2008. / Background This study aimed to define the prevalence of side-effects and the change in weight and BMI during radical radiotherapy for head and neck malignancies (HNM) at Tygerberg Academic Hospital (TBH), Western Cape, South Africa. Acute side-effects may delay or prevent the delivery of a complete curative radiotherapy dose. Weight loss has been shown to significantly worsen prognosis and increase prevalence of treatment complications. However, weight maintenance may lead to beneficial outcomes. Assessing the impact of radical radiotherapy on patients with HNM is therefore critical and can promote development and implementation of medical and nutritional interventions. Methods Patients were weighed before and weekly during radiotherapy. Blood was drawn before, during and at the end of radiotherapy so that the Prognostic Inflammatory and Nutritional Index (PINI) could be calculated. Selected clinical data, clinical grades of mucositis and the diagnosis of a fungal infection of the oral cavity were extracted from clinical records. The McMaster Head and Neck Radiotherapy Questionnaire and a Lifestyle and Dietary Questionnaire were administered weekly. Descriptive statistics and the following were used: ANOVA, Repeated Measures ANOVA and McNemar Chi-square tests. Results Thirty-eight patients were recruited and 21 completed the study. Follow-up occurred over a maximum of nine weeks. A decrease in the weight (p = 0.01) and BMI (p = 0.01) and increase in the PINI (p = 0.04) occurred during radiotherapy. The mean absolute weight loss was 3.2kg (4.8), the mean percentage weight loss was 4.5% (6.7) and the mean decrease in BMI was 1.2kg/m2 (1.8). There was an increase in the prevalence of malnutrition (p = 0.02), as defined in this study. Oral mucositis occurred in all participants from Week 4; the majority developing Grade II or III Mucositis. Fungal infection of the oral cavity was prevalent throughout radiotherapy, with the highest prevalence (30%) in Week 4. Increases in severity of symptoms related to the mouth (p = 0.0000), throat (p = 0.05) and skin domains (p = 0.0000) occurred. Fifty-nine percent of inpatients and 45% of outpatients were prescribed supplementation drinks and most participants reported that a dietitian had not consulted them, in each week of radiotherapy. Discussion Severe side-effects in the mouth, throat and skin were experienced and a decline in nutritional status was observed. The poor nutritional status prior to commencing and weight loss during radiotherapy could have increased the severity of side-effects. The induction of the acute phase response indicated that this could have contributed to the decline in nutritional status observed. In addition, the infrequent nutritional support is likely to have further contributed to the lack of weight maintenance. Conclusion This first study conducted in South Africa has demonstrated the prevalence of significant side-effects and change in weight and BMI in this patient population. It is recommended that more effective analgesic medication is prescribed and that measures are taken to improve oral hygiene of participants to prevent fungal infection of the oral cavity. Improved nutritional support in terms of regular dietetic follow-up of all patients and more frequent prescription of supplementation drinks during radiotherapy is also recommended.

Made available in DSpace on 2015-03-03T11:52:48Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-02-24Bitstream added on 2015-03-03T12:07:01Z : No. of bitstreams: 1 000807311.pdf: 1576554 bytes, checksum: 8c98005febc992a7fec3f6de5d99dd6a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo á Pesquisa do Estado de Minas Gerais (FAPEMIG) / Fundação Oswaldo Cruz (FIOCRUZ) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O câncer epitelial de ovário representa um desafio para Oncologia Ginecológica, devido à sua natureza insidiosa e alta mortalidade. Há também uma compreensão limitada da etiologia da doença ao nível molecular, o que continua a dificultar o desenvolvimento de alvos terapêuticos. Estudos recentes de morfologia, imuno-histoquímica e de genética molecular têm levado ao desenvolvimento de um novo paradigma para a patogênese e a origem do câncer epitelial de ovário, baseado em um modelo dualista de carcinogênese que divide o câncer epitelial de ovário (CEO) em duas grandes categorias chamadas de tipos I e II. O objetivo deste estudo foi avaliar o padrão das citocinas e quimiocinas encontradas no tecido ovariano de mulheres saudáveis e mulheres com CEO tipo I e tipo II. Além disso, descrever a associação desses biomarcadores com os dados clínico-patológicos. Foram analisadas amostras de tecido ovariano e ascite obtidas de mulheres com CEO (n=26) e amostras de tecido ovariano e lavado peritoneal de mulheres sem evidências de malignidade (n=16 - grupo de controle). Nas amostras de tecido, a expressão gênica foi avaliada utilizando a metodologia de PCR quantitativo em tempo real (qPCR) para os genes IFNG, IL-10, TGFB1, CCL2, CCL3, CCL5, CXCL8, CXCL9 e CXCL10. A detecção dos níveis de citoquinas/quimioquinas nos fluidos peritoneais foi realizada através do método Cytometric Bead Array (CBA) os marcadores IL-12p70, TNF, IL-10, IL-6, IL-1--8, IL-17A, IFN-IL-4, IL-2, CCL2, CCL5, CXCL-9 e CXCL-10. No grupo das pacientes com CEO, 10 (38,5%) apresentavam estágios I/II e 16 (61,5%) estágios III/IV. Com relação ao tipo de tumor, de acordo com a nova classificação, 8 (30,8%) eram do tipo I e 18 (69,2 %) do tipo II. A citorredução ótima foi obtida em 15 (57,7%) das mulheres com CEO. Mulheres com CEO tipo II apresentaram maiores níveis séricos do marcador CA-125 quando comparado às do tipo I. Não houve óbito no grupo ... / The epithelial ovarian cancer represents a challenge to Gynecologic Oncology due to its insidious nature and high mortality. There is also a limited understanding of disease etiology at the molecular level, which continues to hamper targeted therapeutic development. Recent morphological, immunohistochemical, and molecular genetic studies have led to the development of a new paradigm for the pathogenesis and origin of epithelial ovarian cancer based on a dualistic model of carcinogenesis that divides epithelial ovarian cancer into 2 broad categories designated types I and II. The aim of this study was to evaluate the cytokines and chemokines pattern in ovarian tissue from healthy women and women with EOC type I and type II. Also, we described the association of these biomarkers with the clinicopathological data. Samples of ovarian tissue and ascite obtained from women with EOC (n=26), samples of ovarian tissue and peritoneal wash from women with no evidence of malignancy were analyzed (n=16 – control group). In the tissue samples, gene expression were evaluated by quantitative real time PCR (qPCR) IFNG, IL-10, TGFB1, CCL2, CCL3, CCL5, CXCL8, CXCL9 and CXCL10. The detection of cytokine/chemokine levels in peritoneal fluids was measured by cytometric bead array immunoassay (CBA), IL-12p70, TNF, IL-10, IL-6, IL-1--8, IL-17A, IFN--4, IL-2, CCL2, CCL5, CXCL-9 and CXCL-10. In the group of women with EOC, 10 (38.5 %) had stage I/II and 16 (61.5 %) were stage III/IV . Concerning tumor type , according to the new classification, 8 (30.8 %) were type I and type II were 18 ( 69.2 % ) . Optimal cytoreduction was achieved in 15 (57.7 %) women with EOC. The CA-125 showed higher serum levels in patients with EOC type II compared to type I. There were no deaths in women with type I tumor while 6 (33.3 %) of patients with type II tumor died . Increased expression of IL-10, CXCL8 and CXCL9 genes in the group of women

Background: Heart damage from cancer therapy is a significant problem for survivors. Some of the most effective treatments, such as anthracyclines, cause heart toxicity that can lead to significant morbidity and mortality. Cardiotoxicity also contributes to the loss of promising cancer drugs in early development and is notoriously difficult to predict. This translational project employs parallel pre-clinical and clinical studies to explore circulating biomarkers and cardiac magnetic resonance imaging (CMR) during development of anthracycline associated cardiotoxicity with the aim of finding biomarkers to aid clinical decision making and enable forward/back translation. Methods: Pre-clinical work: A rat model of chronic anthracycline-induced cardiomyopathy was developed involving 8 weekly intravenous boluses of doxorubicin followed by a 4 week ‘washout’ period. A time course assessment of cardiac function using multiple MRI parameters was performed alongside a panel of circulating biomarkers measured prior to dosing. Clinical work: In parallel following ethical approval, 30 cancer patients receiving standard anthracycline chemotherapy were recruited. Serial CMR scans were performed using standard and new exploratory techniques before, during and after treatment and blood was taken to evaluate a similar panel of cardiotoxicity biomarkers using multiplex ELISA at corresponding time points. Results: Pre-clinical results: Systolic and diastolic function declined progressively, culminating in left ventricular dysfunction (LVEF < 50%) by 12 weeks. Myocardial electron microscopy revealed myofibrillar and mitochondrial damage after one dose and gross histopathological damage after 5 doses. Myocardial contrast enhancement and troponin I increased significantly after eight doses and preceded LV dysfunction. Extensive fibrosis was seen 1 month after drug cessation. Clinical results: LVEF declined progressively in all patients and 7 patients (23%) had persistent LV dysfunction 12 months after therapy. Troponin I elevations were seen towards the end of therapy and peak troponin I corresponded with LVEF decline. None of the other circulating biomarkers correlated strongly with outcome. Lower baseline extracellular volume (ECV) was associated with greater LVEF decline but little change in ECV was seen over time. Baseline dyssynchrony was associated with worse outcome and deteriorated with time alongside LVEF decline. Conclusions: Results suggest that troponin I and cardiac MRI are sensitive translational tools in drug induced cardiotoxicity. However, troponin I is a relatively late marker, peaking after substantial myocardial damage, too late to halt or change reatment. The imaging suggests that fibrosis and inflammation cannot be detected within a year of chemotherapy but baseline ECV and strain analysis may have a role in risk stratification.

FLIP (FLICE inhibitory protein) est une protéine anti-apoptotique qui a des identités de séquence partagées avec la protéine pro-apoptotique caspase-8. FLIP se trouve en compétence avec caspase-8 pour se fixer sur la protéine adaptatrice FADD, ce qui empêche l’activation de caspase-8 bloquant ainsi l'apoptose. Lors du développement des molécules interférant avec des protéines anti-apoptotiques, la recherche d'inhibiteurs de la protéine FLIP qui est surexprimée dans un très grand nombre de cancers, a échoué. Cela s'explique en partie par le fait que peu d'information structurelle de FLIP est actuellement disponible TRAIL est une cytokine de la famille TNFα. Elle est décrite pour activer des voies de signalisation conduisant à la mort cellulaire par apoptose. TRAIL a montré un grand intérêt dans la thérapie anticancéreuse, grâce à sa capacité d’induire la mort des cellules tumorales sans aucun effet sur les cellules normales. Cependant, l’efficacité de TRAIL est limitée par plusieurs mécanismes moléculaires. Un de ces mécanismes est la surexpression de FLIP qui fait compromettre l’utilisation thérapeutique de TRAIL. Le but principal de ce projet est de développer des nouvelles molécules capables d’inhiber la protéine FLIP dans les cellules tumorales, sans aucun effet sur la protéine homologue caspase-8. Après modélisation des protéines FLIP et caspase-8 sur la base de la structure cristallographique de FLIP viral et FADD respectivement, des premières expériences d’ancrage ou “docking” utilisant une banque de composés chimiques du «National Cancer Institute NCI » ont été réalisées. Les 9 molécules les plus intéressantes, étant comme sélectives pour FLIP et non caspase 8, ont été sélectionnées et testées sur des lignées de cancer de poumons surexprimant la protéine FLIP. Une co-administration de chacune des molécules inhibitrices de FLIP avec TRAIL a été faite pour vérifier la restauration de la voie apoptotique dans les cellules cancéreuses. Un test moléculaire de « Pull down assay » a été fait afin de confirmer l’inhibition de l’interaction de FLIP avec FADD. Finalement, l’évaluation de l’activité enzymatique des caspases a été étudiée pour vérifier la réactivation de la voie apoptotique après la combinaison de TRAIL avec les inhibiteurs de c-FLIP. En conclusion, la combinaison de TRAIL avec les inhibiteurs de FLIP aboutit à la restauration de la voie apoptotique dans des cellules cancéreuses. Ces composés nouvellement identifiés, peuvent servir ultérieurement comme des potentiels éléments des stratégies utilisées dans le domaine du traitement du cancer. / FLIP (FLICE Inhibitory Protein) is an anti-apoptotic protein which shares sequencesimilarity with the pro-apoptotic protein caspase-8. FLIP competes with caspase-8 for binding to the adaptor protein FADD (Fas-associated death domain), thus it inhibits caspase-8 activation, thereby blocking apoptosis. During the development of molecules interfering with anti-apoptotic proteins, searching for inhibitors of FLIP protein which is overexpressed in a very large number of cancers, has failed. This is partly due to the fact that little FLIP structural information is available at present. TRAIL is a member of TNFα superfamily. It has been described to activate the apoptotic signaling pathways. TRAIL showed great interest in anti-cancer therapy, due to its ability to induce tumor cell death without any effect on normal cells. However, the efficacy of TRAIL is limited by several molecular mechanisms. One of these mechanisms is the overexpression of FLIP which is able to compromise the therapeutic use of TRAIL. The main goal of this project is to develop novel inhibitory molecules able to interfere with FLIP in tumor cells without any effect on the homologous protein caspase 8. After the construction of FLIP and caspase-8 proteins on the basis of the crystallographic structure of the viral FLIP and FADD respectively, the first docking experiments using a chemical library of the National Cancer Institute NCI have been carried out. The most interesting molecules, being selective for FLIP versus caspase 8, were selected and tested on lung cancer cell lines that overexpress FLIP protein. Co-administration of FLIP inhibitors with TRAIL was performed to verify the restoration of the apoptotic pathway in cancer cells. A molecular test of "Pull down assay" was done in order to confirm the inhibition of the FLIP/FADD interaction. Finally, the evaluation of caspases activity was carried out to confirm the reactivation of the apoptotic machinery after TRAIL/FLIP-inhibitors combination. In conclusion, the combination of TRAIL with FLIP inhibitors resulted in apoptosis restoration in resistant tumor cells. These newly identified compounds may serve later as potential elements in cancer treatment field.