Introdução: o sarcoma de Ewing é um dos tipo mais agressivos de câncer pediátrico. Esse tipo de câncer é um tumor primitivo neuroectodérmico, grupo que inclui ainda outros tumores pediátricos como o meduloblastoma e o neuroblastoma. Apesar de avanços significativos desde o surgimento da quimioterapia, ainda há necessidade de aumento dos índices de cura, redução da toxicidade da quimioterapia e redução da resistência ao tratamento em pacientes com essa doença. Inibidores da acetilação de histonas (HDACIs ou HDIs) e bifosfonatos têm um futuro promissor no tratamento de câncer, especialmente quando utilizados conjuntamente ou em associação com outros agentes citotóxicos, como antineoplásicos clássicos. No entanto, os efeitos destes tratamentos combinados ainda não haviam sido devidamente estudados em Sarcoma de Ewing. Objetivos: este estudo se propôs a avaliar, in vitro, os efeitos do inibidor da acetilação de histonas, butirato sódico (NaB), do bifosfonato, zoledronato (ZA), da associação destes dois agentes e de combinações dos mesmos com antineoplásicos clássicos sobre a proliferação, viabilidade e sobrevivência celular em sarcoma de Ewing. Métodos: as linhagens celulares de sarcoma de Ewing, SK-ES-1 e RD-ES, foram tratadas com NaB, ZA, doxorrubicina, etoposídeo ou vincristina e com diferentes combinações destes agentes. O crescimento tumoral in vitro, incluindo parâmetros de proliferação e viabilidade celular, foi analisado pelos métodos de contagem celular por exclusão com azul de tripan e MTT. Os efeitos tardios (sobrevivência) também foram estudados através da determinação da formação de colônias (ensaio colonogênico). Resultados: a combinação de NaB e ZA teve um efeito citotóxico sinérgico 72h após o tratamento, persistindo durante 10-14 dias após o tratamento, em ambas as linhagens celulares testadas. Todas as combinações entre NaB ou ZA e os antineoplásicos clássicos testados apresentaram efeitos citotóxicos sinérgicos 72h após os tratamentos em ambas linhagens celulares, com a exceção das seguintes associações: NaB + VCR e ZA + Doxo, que apresentaram apenas efeito aditivo nas células RD-ES, quando comparados com cada um dos agentes em monoterapia. Estes efeitos “agudos” observados em ambas as linhagens celulares de sarcoma de Ewing foram confirmados pelo ensaio clonogênico. Conclusão: os dados obtidos sugerem que o uso combinado de bifosfonatos e HDIs e a associação destes agentes com quimioterápicos clássicos representam promissoras alternativas no tratamento de sarcoma de Ewing e proporcionam a base para novos estudos. / Background: Ewing sarcoma, often referred to as Ewing’s sarcoma family tumors, is a peripheral primitive neuroectodermal tumor. Ewing sarcoma is the second most common solid bone and soft tissue malignancy of children and young adults. Despite significant advances in cancer chemotherapy, there is still need for increased rates of cure, reduction of toxicity of chemotherapy and reduced resistance to treatment in patients with this disease. Histone deacetylase inhibitors (HDACIs or HDIs) and bisphosphonates have a promising future in the treatment of cancer as targeted anticancer drugs, especially when used together or in combination with other cytotoxic agents. However, the effects of these combined treatments have not yet been properly evaluated in Ewing sarcoma. Objective: In the present study, we evaluated the in vitro cytotoxic effects (on cellular proliferation, viability, and survival) elicited by the co-treatment of sodium butyrate (NaB) and zoledronic acid (ZA) alone or in combination with three anti-cancer drugs strongly recommended to treat Ewing sarcoma (doxorubicin, etoposide and vincristine) in two human cell lines. Methods: two Ewing sarcoma cell lines, SK-ES-1 and RD-ES, were treated with NaB, ZA, doxorubicin, etoposide, vincristine and with different combinations of these drugs. The proliferation and cell viability were analyzed by counting cell in a hemocytometer, by exclusion of trypan blue and by MTT assay. The survival and proliferation of cells were also studied by clonogenic assay. Results: our results demonstrate that the combination of NaB and ZA has a synergistic cytotoxic effect at 72h after treatment, persisting for 10-14 days post-treatment, in both cell lines tested. All combinations between NaB or ZA and classical antineoplastic drugs demonstrated a synergistic cytotoxic effect at 72h post-treatment in SK-ES-1 and RD-ES cells, with the exception of NaB plus VCR, and ZA plus Doxo, which showed only an additive effect in RD-ES cells when compared to each agent alone. These acute effects observed in both Ewing sarcoma cells were confirmed by the clonogenic assay. Conclusion: These data suggest that HDIs and bisphosphonate co-treatment in combination with classical chemotherapeutic drugs is a promising therapeutic venue the treatment of Ewing sarcoma, and provide a basis for further study in this field.

No description available.

<p>Neuroblastoma is a childhood cancer that originates from neuroblasts in the peripheral nervous system. Neuroblastoma show considerable heterogeneity with respect to location, responsiveness to treatment and prognosis. Since current therapy involves drugs with risk of serious side effects in the growing child, there is a clinical need for more effective and less toxic treatment strategies.</p><p>Angiogenesis, the formation of new blood vessels, is critical for tumor progression. Specific inhibition of tumor-induced angiogenesis should restrict growth of most solid tumors and thereby provide a new treatment strategy. The aim of this study was to investigate the effects of angiogenic inhibition in experimental neuroblastoma in mice.</p><p>We found that experimental neuroblastomas expressed the perhaps most potent angiogenic growth factor, VEGF-A, and that plasma VEGF-A levels correlated with tumor size. SU5416, a novel antagonist of VEGFR-1 and 2, reduced angiogenesis and tumor growth in our model. We also investigated the properties of SU11657, a new, orally available, synthetic small molecule multi-targeted tyrosine kinase inhibitor. SU11657, at a well-tolerated dose, was more potent than SU5416 in reducing tumor growth rate and angiogenesis, even in MYCN-amplified tumors. Chemotherapeutics can also inhibit angiogenesis, when administrated daily in a non-toxic dose. CHS 828, a new chemotherapeutic, given orally, alone induced complete neuroblastoma regression in 44 % of the animals. Furthermore, the bisphosphonate zoledronic acid, developed to reduce bone resorption, showed anti-tumor activity in our model. Zoledronic acid was more potent than the angiogenic inhibitor TNP-470. Thus bisphosphonates may have other beneficial properties in patients with cancer apart from preventing bone resorption.</p><p>In conclusion, SU5416, SU11657, CHS 828, and zoledronic acid represent new drugs with potent anti-tumor effects. Angiogenic inhibition as single therapy or in combination with chemotherapeutics may be beneficial in the treatment of rapidly growing and highly vascularized solid tumors of childhood such as neuroblastoma.</p>

Neuroblastoma is a childhood cancer that originates from neuroblasts in the peripheral nervous system. Neuroblastoma show considerable heterogeneity with respect to location, responsiveness to treatment and prognosis. Since current therapy involves drugs with risk of serious side effects in the growing child, there is a clinical need for more effective and less toxic treatment strategies. Angiogenesis, the formation of new blood vessels, is critical for tumor progression. Specific inhibition of tumor-induced angiogenesis should restrict growth of most solid tumors and thereby provide a new treatment strategy. The aim of this study was to investigate the effects of angiogenic inhibition in experimental neuroblastoma in mice. We found that experimental neuroblastomas expressed the perhaps most potent angiogenic growth factor, VEGF-A, and that plasma VEGF-A levels correlated with tumor size. SU5416, a novel antagonist of VEGFR-1 and 2, reduced angiogenesis and tumor growth in our model. We also investigated the properties of SU11657, a new, orally available, synthetic small molecule multi-targeted tyrosine kinase inhibitor. SU11657, at a well-tolerated dose, was more potent than SU5416 in reducing tumor growth rate and angiogenesis, even in MYCN-amplified tumors. Chemotherapeutics can also inhibit angiogenesis, when administrated daily in a non-toxic dose. CHS 828, a new chemotherapeutic, given orally, alone induced complete neuroblastoma regression in 44 % of the animals. Furthermore, the bisphosphonate zoledronic acid, developed to reduce bone resorption, showed anti-tumor activity in our model. Zoledronic acid was more potent than the angiogenic inhibitor TNP-470. Thus bisphosphonates may have other beneficial properties in patients with cancer apart from preventing bone resorption. In conclusion, SU5416, SU11657, CHS 828, and zoledronic acid represent new drugs with potent anti-tumor effects. Angiogenic inhibition as single therapy or in combination with chemotherapeutics may be beneficial in the treatment of rapidly growing and highly vascularized solid tumors of childhood such as neuroblastoma.

Το πολλαπλούν μυέλωμα είναι μια νεοπλασία η οποία, έως και σήμερα, παραμένει ανίατη. Στο ΠΜ, το ανοσοποιητικό σύστημα δε κατορθώνει να καταστρέψει τα κακοήθη πλασμοκύτταρα, ενώ υπάρχουν ενδείξεις ότι τα κύτταρα του όγκου παίζουν ενεργό ρόλο σε αυτό. Στην παρούσα διατριβή, ελέγξαμε ποικίλλες μυελωματικές σειρές σχετικά με την έκφραση των προ- και αντι-αποπτωτικών γονιδίων. Βρήκαμε ότι τα μυελωματικά κύτταρα εκφράζουν έναν μη φυσιολογικό φαινότυπο (fas high/bcl low). Μελετώντας τα κύτταρα του μυελού των οστών ενός ασθενούς με ΠΜ τύπου IgG/k σταδίου ΙΙΙΑ, διαπιστώσαμε ότι αυτά τα κύτταρα εξέφραζαν τα γονίδια granzyme B και perforin, τα οποία υπό κανονικές συνθήκες εκφράζονται μόνο από τα κυτταροτοξικά Τ λεμφοκύτταρα (CTLs) και τα φυσικά φονικά κύτταρα (ΝΚ). Προτείνουμε ότι πιθανόν το παραπάνω γεγονός αποτελεί έναν επιπλέον αμυντικό μηχανισμό των κυττάρων του όγκου εναντίον των CTLs και ΝΚ κυττάρων. Συγκεκριμένα υποθέτουμε ότι τα κύτταρα του όγκου προσελκύουν τα CTLs και τα ΝΚ κύτταρα και τα καταστρέφουν με τη διαδικασία της κυτταρόλυσης. Τα διφωσφονικά οξέα χρησιμοποιούνται ευρέως για τη θεραπεία του ΠΜ, ενώ η θαλιδομίδη χρησιμοποιείται σήμερα για τη θεραπεία πολλών τύπων ΠΜ. Μελετήσαμε την επίδραση της θαλιδομίδης, του ζολεδρονικού οξέος και το συνδυασμό τους στην επιβίωση των μυελωματικών κυττάρων. Βρήκαμε ένα συνεργιστικό αποτέλεσμα των δύο αυτών ουσιών. Όταν η θαλιδομίδη συγχοηγηθεί με το ζολεδρονικό οξύ σε ελάχιστους μη δραστικούς μηχανισμούς, μειώνει την τοξική επίδραση 50% του τελευταίου 3-4 φορές. / Multiple Myeloma (MM) is a plasma cell neoplasia which, to this day, remains incurable. In MM, the immune system fails to destroy the malignant plasmocytes, and evidence exists that the tumor plays an active part in this. In the present study, we tested various MM cell lines for the expression of pro- and anti-apoptotic genes. We found that MM cells express an abnormal phenotype, namely fas high/bcl low. By studying bone marrow cells from a patient suffering of MM IgG/k type stage IIIA, we found that those cells expressed granzyme B nad perforin, normally expressed by cytotoxic T cells (CTLs) and natural killer (NK) cells. We propose that this may constitute an additional acquired mechanism by the tumor cells to protect themselves against the host.

Les effets des agents anti-ostéoporotiques sur le tissu osseux sont évalués au niveau de la crête iliaque (CI) mais les réponses aux traitements peuvent varier selon le site osseux. Le but de cette étude était de comprarer les effets de l’acide zolérodronique (ZOL) et du tériparatide (TPTD) au niveau de la crête iliaque et de la vertèbre lombaire L1 (VL1) chez la brebis âgée. Le ZOL a induit une forte diminution du remodelage osseux et une augmentation des microendommagements au niveau des deux sites et une modification des crosslinks du collagène surtout au niveau de l’os cortical de la CI. Trois mois de TPTD ont augmenté le remodelage osseux uniquement au niveau de la VL1. En conclusion, les délais et les amplitudes de réponses au ZOL ou au TPTD diffèrent entre la CI et la VL1 chez la brebis. Ces résultats montrent l’importance de prendre en compte le site osseux pour évaluer les effets des agents anti-ostéoporotiques / The effects of anti-osteoporotic agents on bone tissue are evaluated on iliac crest (IC) but the answers to treatments may vary according to the skeletal site. The purpose of this study was to compare the effect of zoledronic acid (ZOL) and teriparatide (TPTD) on IC and lumbar vertebrae (LV1) in ewes. ZOL has induced a high decrease of bone remodeling, an increase in microdamages in both sites and a modification of collagen crosslinks mainly in cortical bone of IC. Three months of TPTD has increased the bone remodeling only in LV1. In conclusion, the delays and the magnitudes of responses to ZOL or to TPTD differ between IC and LV1 in ewes. These results show that the distinction of bone sites to study the early effects of antiosteoporotic therapies appears meaningful

The skeletal system is the most common site of metastatic cancer spread. Bone metastases are often associated with severe morbidity, pain and functional impairment. Timely diagnosis and proper treatment may decrease morbidity, improve quality of life and in some cases even improve survival. External beam radiotherapy may effectively give pain relief in patients with painful bone metastases. In bone metastases from castration-resistant prostate cancer or urothelial bladder cancer, treatment with zoledronic acid or denosumab may reduce skeletal-related events. In contrast to castration-resistant prostate cancer, in patients with bone metastases from bladder cancer such treatment may even improve survival. On the other hand, the efficacy of these agents is questionable in patients with bone involvement from metastatic renal cell carcinoma or germ cell tumors. When bisphosphonates or denosumab are considered in such cases, the potential benefits of treatment should be critically weighed against the risk of side effects. In germ cell tumors, bone metastases may be cured by cisplatin-based chemotherapy, however, there are only limited data on the specific management of residual disease. Oligometastases may be treated by stereotactic radiotherapy or – especially in patients with renal cell carcinoma – by surgical resection and endoprosthetic replacement. Limited data are available on the management of bone involvement in germ cell tumors. Decisions on the resection or local radiotherapy of residual disease should be individualized considering the overall response and the feasibility and risks of resection.

No description available.