Cancer is a global epidemic; over 1.5 million new cancer diagnoses and greater than 600,000 deaths due to cancer are estimated to occur in the United States within the year 2015 alone. Approximately two-thirds of patients with bone metastases will experience pain, pathological fractures, spinal cord or nerve root compression, paralysis, impaired mobility, bone marrow infiltration and hypercalcemia of malignancy. We induced bone metastases through inoculation of rat femurs with MDA-MB-231 human breast cancer cells in order to compare the effectiveness of various treatment modalities, disease progression and recovery through the use of imaging methods in current clinical practice. CTRA provides highly accurate monitoring of metastases progression and treatment through both Ibandronate and Paclitaxel therapies. Using computed tomography (QCT)-based analysis to calculate the load bearing capacity of bone infiltrated with metastatic breast carcinoma, fracture risk threshold was predicted using Computed Topography Rigidity Analysis (CTRA) with 100% sensitivity and 90% specificity. The results of this study further validate that there is an existing gap between clinical guidelines and physician’s recommendations. This inconsistency necessitates that the decision making process for the selection of surgical or non-surgical treatment must be narrowed by more advanced prognostic tools such as CTRA.

abstract: Prophylactic bilateral mastectomy (PBM) is the current recommended course of action for women with increased genetic risk for breast and ovarian cancer. Nevertheless, many receive negative feedback from family and friends surrounding the decision to undergo this surgery because they do not have cancer when the decision is made; this results in a limited support network for coping with their PBM. Low social support is associated with depression, negativity, and anxiety. Women who had a PBM, were currently undergoing or had completed reconstruction, and were in a committed romantic relationship at the time of the surgery were surveyed (N = 53). The hypotheses that women who received negative feedback about their decision to have a PBM would have poorer individual well-being, and that the use of a couples-based team approach would moderate these adverse effects were tested. Data analyses support the hypotheses that women in couples taking a team approach to PBM have better individual well-being. The effects of negative feedback from others about the decision to undergo a PBM on personal mental health were moderated by use of a couples-based team approach. Women who received negative feedback from multiple sources had better outcomes if they used a couples-based team approach. Many women have a preventative oophorectomy around the same time as their PBM. Menopause is associated with side effects such as increased vasomotor symptoms and decreased sexual functioning. The hypothesis that surgical menopause is related to declines in sexual satisfaction following PBM was also tested. Regression analysis revealed no relationship. This study indicates that women who experience social disapproval and lack collaborative support from their significant other may be at increased risk for poor individual well-being following PBM. / Dissertation/Thesis / Masters Thesis Psychology 2018

Poly(ADP-ribose)polymerase-1 and -2 (PARP1/2) are nuclear proteins involved in DNA repair. Tumors with defects in homologous recombination, including BRCA1- and BRCA2-deficient cancers, have been shown to be sensitive to PARP inhibition. The Weissleder group has synthesized fluorescent and radioactive derivatives of the PARP1/2 inhibitor AZD2281. We hypothesized that fluorescent and radioactive AZD2281-based imaging agents would quantify PARP1/2 expression in vitro and in vivo. To test this hypothesis, a panel of pancreatic ductal adenocarcinoma and ovarian carcinoma cell lines were characterized by immunocytochemistry for PARP1/2 expression. AZD2281-derived fluorescence signal correlated with anti-PARP antibody fluorescence signal strength in vitro. Four cell lines representing a range of PARP1/2 expression levels were then xenografted into Nu/Nu mice. Mice bearing four tumor types each were imaged with AZD2281-derived imaging agents, sacrificed, and their tumors excised for stand-alone imaging and Western blot. AZD2281-derived signal correlated with tumor PARP1/2 expression determined by Western blot, indicating that PARP1/2 expression level is a determinant of fluorescent signal strength and SUVs of AZD2281-derived agents in vivo. These data indicate that AZD2281-derived agents are useful tools for quantifying intracellular PARP1/2 both in vitro and in vivo, which could one day enable prospective identification of tumors likely to respond to PARP inhibitors.

Bakgrund: BRCA-mutation är en ärftlig mutation som ökar risken för bröst- och ovarialcancer hos kvinnor. Kvinnor med BRCA-mutation får genomgå ökad bevakning hos sjukvården samt ställs inför profylaktiska val. Det här kan komma att påverka kvinnan på flera olika sätt. Vården bör därför ha förståelse för kvinnorna och deras upplevelser samt vad som kan vara betydelsefullt för kvinnornas fortsatta liv med en BRCA-mutation. Syfte: Syftet var att belysa kvinnors upplevelser av att leva med BRCA-mutation. Metod: En litteraturöversikt med induktiv ansats som baserades på tio kvalitativa vetenskapliga artiklar. Data analyserades utifrån Fribergs (2017) modell för allmän litteraturöversikt. Resultat: Analysen resulterade i tre kategorier med fyra tillhörande underkategorier. Kategorierna benämns; Osäker framtid, förändrad kropp och behov av stöd. Slutsats: Studiens resultat visar att kvinnor med BRCA-mutation påverkas både fysiskt och psykiskt och står inför beslut som kan komma att påverka hela deras liv. Att kvinnorna behöver mer stöd är ett faktum och där krävs det att vården innehar en ökad kunskap och förståelse för dessa kvinnor. Detta för att kvinnorna ska kunna få det stöd de behöver utefter deras individuella behov, i deras plötsligt förändrade livsvärld.

OBJECTIVE: Despite advancement in targeted therapeutics, women’s cancers remain particularly deadly. The response to Poly (ADP-ribose) Polymerase (PARP) inhibitors, a prominent targeted therapy indicated for use in these cancers, is largely dictated by the cellular status of homologous recombination (HR) and varies among patients possibly due to intrinsic and acquired mechanisms of resistance. A recent effort to identify targetable pathways to enhance toxicity of PARPi identified the Snf2-like chromatin remodeling enzyme, Amplified in Liver Cancer 1 (ALC1), as a key determinant of PARPi sensitivity. While this discovery proposes a link between chromatin re-modeling and PARPi sensitivity, the mechanism underlying the relationship remains unclear. This study aims to validate ALC1 as a determinant of PARPi sensitivity, characterize the phenotype of ALC1 loss, investigate mechanisms of synthetic lethality and identify possibilities for future studies and clinical implementation. METHODS: UWB1.289, SUM149PT, DLD1, U-2 OS, and hTERT-RPE1 cells were cultured and used to validate ALC1-mediated PARPi sensitivity in a variety of viability assays. ALC1 depleted cells were complemented with various functional mutants to assess protein domains that were essential to PARPi-resistance. A Dual CRISPR-Cas9 system was implemented to screen BRCA1 complemented UWB1.289 cells with a sgRNA library targeting a multitude of DNA-repair associated genes in order to assess synthetic lethal/resistant relationships across different DNA-repair pathways. A MNase-sensitivity assay was developed and optimized to assess the global condensation of chromatin with combinational loss of ALC1 and PARP1. The 265-FokI system was employed to quantify the DNA damage response (DDR) to singular induced double strand breaks. Clonogenic assays were used to determine synergy with ionizing radiation. RESULTS: The loss of ALC1 significantly and selectively hypersensitized both BRCA1 and BRCA2-deficient cells to PARPi. In ALC1 depleted cells, the addition of ALC1 cDNA was able to rescue cells from PARPi hypersensitivity while cDNA with mutations in either the macro-domain or ATPase active domain remained sensitive. Screening DNA-repair pathways to assess synergy with PARPi and ALC1 loss in HR-proficient settings revealed that the loss of several HR and Alt-EJ genes selectively re-sensitized cells to PARPi. Interestingly, the loss of BER genes, including several glycosylases, were epistatic or resulted in a protective effect to PARPi. The reduction of NHEJ, NER, MMR or RER did not significantly alter cellular response to PARPi. Further, nucleosome relaxation was significantly inhibited in cells treated with PARPi, ALC1 loss or in combination via MNase assay. The recruitment of repair proteins to DSBs was significantly inhibited by PARPi as assessed by 265-FokI immunofluorescence. The addition of PARPi in the setting of ALC1 loss significantly increased the cytotoxicity of ionizing radiation. Analyzing TCGA data collected from patients’ tumors, ALC1 may be overexpressed in many cancers and alterations in ALC1 may predict patient responses to traditional and targeted cancer therapies. CONCLUSION: Using various models of BRCA1/2 deficiency we were able to validate the ability of ALC1 depletion to hypersensitize HR-deficient cells to PARPi. We provided insight into the mechanisms by which this phenomenon may be taking place, including chromatin compaction and the inhibition of DNA-damage repair. In addition, we provided therapeutic rationale that ALC1 may be targeted with PARP1 in synergy with other DNA-damaging agents. Overall, we believe that ALC1 is a prominent, viable and novel target of inducing PARP inhibitor sensitivity, that may help improve outcomes for patients with PARP inhibitor-resistant HR-deficient cancers. / 2022-06-04T00:00:00Z

Breast cancer is the most commonly diagnosed cancer in women in the United States and is the leading cause of cancer-related death among women worldwide. Certain demographics, such as racial/ethnic, age, and gender groups, are underrepresented in breast cancer studies. This lack of representation results in issues with creating genetic tests, as variants associated with those groups are not being detected. Furthermore, these underrepresented demographics are receiving a worse prognosis than those that are overrepresented in research. This study aimed to understand how informed the understudied racial/ethnic, gender, and age populations are regarding breast cancer and genetic testing compared to populations that have been abundantly studied, and the factors affecting the decision to receive genetic testing between gender groups. After distributing a survey to students at the University of Central Florida, the study found that females answered the knowledge-based questions more accurately than males; however, no significant differences were found between age or ethnicity groups. This is likely due to the sample consisting of university students who are more knowledgeable than the general population. The study found a negative correlation between gender and the influence of individual health concerns on receiving genetic testing and how often a breast self-exam is performed. A difference was also found between gender, age, and ethnic groups on having performed a breast self-exam. Further investigations should sample from a general population or other university populations for comparison. Also, increased education on breast cancer risks, performing a breast self-exam, and receiving genetic testing would be beneficial for early detection of breast cancer.

The deregulation of the MYC oncoprotein family plays a major role in tumorigenesis and tumour maintenance of many human tumours. Because of their structure and nuclear localisation, they are defined as undruggable targets which makes it difficult to find direct therapeutic approaches. An alternative approach for targeting MYC-driven tumours is the identification and targeting of partner proteins which score as essential in a synthetic lethality screen. Neuroblastoma, an aggressive entity of MYCN-driven tumours coming along with a bad prognosis, are dependent on the tumour suppressor protein BRCA1 as synthetic lethal data showed. BRCA1 is recruited to promoter regions in a MYCN-dependent manner. The aim of this study was to characterise the role of BRCA1 in neuroblastoma with molecular biological methods. BRCA1 prevents the accumulation of RNA Polymerase II (RNAPII) at the promoter region. Its absence results in the formation of DNA/RNA-hybrids, so called R-loops, and DNA damage. To prevent the accumulation of RNAPII, the cell uses DCP1A, a decapping factor known for its cytoplasmatic and nuclear role in mRNA decay. It is the priming factor in the removal of the protective 5’CAP of mRNA, which leads to degradation by exonucleases. BRCA1 is necessary for the chromatin recruitment of DCP1A and its proximity to RNAPII. Cells showed upon acute activation of MYCN a higher dependency on DCP1A. Its activity prevents the deregulation of transcription and leads to proper coordination of transcription and replication. The deregulation of transcription in the absence of DCP1A results in replication fork stalling and leads to activation of the Ataxia telangiectasia and Rad3 related (ATR) kinase. The result is a disturbed cell proliferation to the point of increased apoptosis. The activation of the ATR kinase pathway in the situation where DCP1A is knocked down and MYCN is activated, makes those cells more vulnerable for the treatment with ATR inhibitors. In summary, the tumour suppressor protein BRCA1 and the decapping factor DCP1A, mainly known for its function in the cytoplasm, have a new nuclear role in a MYCN-dependent context. This study shows their essentiality in the coordination of transcription and replication which leads to an unrestrained growth of tumour cells if uncontrolled. / Die MYC Onkoproteine spielen in einer Vielzahl humaner Tumore eine entscheidende Rolle und sind in fast allen Fällen dereguliert. Aufgrund ihrer Struktur und Lokalisation im Zellkern gelten sie für die Arzneimittelentwicklung als therapeutisch schwer angreifbar. Der Ansatz der synthetischen Lethalität ist es, Partnerproteine zu finden, die gerade für MYC-getriebene Tumore essenziell sind und diese zu inhibieren. Neuroblastome, die in einer besonders aggressiven Entität durch eine MYCN-Amplifikation getrieben sind und damit mit einer schlechten Prognose einhergehen, sind abhängig vom Tumorsupressor BRCA1, wie Daten zur synthetischen Lethalität zeigten. BRCA1 wird in Abhängigkeit von MYCN zu Promotoren rekrutiert. Diese Arbeit diente daher der Charakterisierung der Funktionalität von BRCA1 im Neuroblastom. BRCA1 verhindert die Akkumulation von RNA Polymerase II (RNAPII) in der Promoterregion. Ist BRCA1 nicht präsent, führt dies zur Bildung von DNA/RNA-Hybriden, sogenannten R-loops, und zu DNA Schäden. Um die Akkumulation von RNAPII zu verhindern, nutzt die Zelle DCP1A, einen Decapping Faktor, der sowohl im Cytoplasma als auch im Nukleus eine Rolle im mRNA Abbau spielt. DCP1A entfernt den schützenden 5’CAP der mRNA, wodurch diese von Exonukleasen abgebaut wird. BRCA1 ist notwendig für die Chromatin Bindung von DCP1A und die Rekrutierung zu RNAPII. Zellen mit einer akuten Aktivierung des MYCN Onkoproteins zeigen eine erhöhte Abhängigkeit von DCP1A. DCP1A verhindert eine Deregulation der Transkription, um Transkription mit Replikation erfolgreich zu koordinieren. Andernfalls führt dies beim Verlust von DCP1A zur Blockierung von Replikationsgabeln und der Aktivierung der Ataxia telangiectasia and Rad3 related (ATR) Kinase führt. In der Folge ist das Zellwachstum gestört und Zellen gehen vermehrt in Apoptose. Die Aktivierung des ATR Signalweges beim Verlust von DCP1A und MYCN Aktivierung verhindert vorerst den Zelltod, wodurch diese Zellen jedoch sensitiver auf die Inhibition von ATR reagieren. Zusammenfassend lässt sich sagen, dass BRCA1 als Tumorsupressor und DCP1A als Decapping Faktor, hauptsächlich beschrieben als cytoplasmatisches Protein, eine entscheidende nukleäre Rolle in der Situation einer akuten Aktivierung von MYCN spielen. Dort sind sie essenziell um Transkription mit Replikation zu koordinieren und damit zu einem ungebremsten Wachstum der Tumorzellen beizutragen.

No description available.

PARP inhibitors (PARPi) have been used to induce synthetic lethality in BRCA-deficient tumors in clinical trials with limited success due to the development of resistance to PARPi. BRCA-deficient cells are unable to repair DNA double strand breaks by the accurate homologous recombination repair (HR), and therefore rely on alternative DNA repair pathways for survival. We hypothesized that RAD52-mediated DNA repair mechanisms remain active and are thus protecting some PARPi-treated BRCA-deficient tumor cells from apoptosis, and that targeting RAD52 should enhance the synthetic lethal effect of PARPi. We show here that RAD52 inhibitors (RAD52i) attenuated single-strand annealing (SSA) and residual HR activity in BRCA-deficient cells. Simultaneous targeting of PARP1 and RAD52 with small molecule inhibitors or via expression of dominant-negative mutants induced an accumulation of DSBs and selective eradication of BRCA-deficient solid tumor and leukemia cells, while BRCA-proficient cells were unaffected. Parp1-/-Rad52-/- transgenic mice are healthy and indistinguishable from wild-type mice due to the presence of the BRCA-pathway, and Parp1-/-Rad52-/- mice with inducible BRCA1-deficient leukemia displayed significantly prolonged survival when compared to Parp1-/- and Rad52-/- counterparts. Finally, PARPi + RAD52i selectively targeted BRCA1-deficient solid tumors in immunodeficient mice with minimal toxicity to normal cells and tissues which are protected by the BRCA-pathway, indicating minimal side effects. In conclusion, our data indicate that combination treatment of RAD52i and PARPi will significantly improve therapeutic outcome of BRCA-deficient malignancies compared to treatment with PARPi monotherapy, while leaving healthy cells and tissues unharmed. / Biomedical Sciences

In general population 1 of 72 women develop ovarian cancer and to 1 of 95 women this disease is lethal. A great number of clinical trials have shown that the course of the disease is not dependent only on the classical prognostic indicators such as histological tumor type, tumor differentiation, stage of the disease or treatment modalities. More than two decades ago the first publications on heredity factors indicated similarity among the patients diagnosed ovarian malignancies and their first degree relatives. The first genetic autosomal dominant inheritance was determined in the high-risk cancer tumor suppressor BRCA1/2 genes. In spite of the abundant number of trials studying the BRCA1/2 genes role in breast and ovarian carcinogenesis still it is not sufficiently clear the influence of these genes for the disease prognosis. The aim of our conducted trial was to determine the BRCA1/2 genes prognostic significance for progression-free and overall survival in the event of advanced ovarian cancer. In case of advanced ovarian cancer the BRCA1/2 mutation frequency was 51,4 %. Among all determined BRCA1/2 gene mutations BRCA1 4035delA or founder mutation was most frequent. It amounted to 63.6%. Non-optimal cytoreduction (p<0,0001 ) , patients’ older age (p=0,005) and absence of BRCA1/2 mutations (p=0,049) are closely connected with a shorter PFS and OS. Only non-optimal cytoreduction was related to a shorter OS (p=0,010). / Bendrojoje populiacijoje 1 iš 72 moterų suserga kiaušidžių vėžiu ir 1 iš 95 moterų miršta nuo šios ligos. Tyrimų duomenys rodo, kad ligos eiga nėra priklausoma vien tik nuo klasikinių prognozinių rodiklių, tokių kaip histologinis naviko tipas, naviko diferenciacija, ligos stadija, taikytas gydymas.Prognozinių veiksnių paieška krypstą link genetinių veiksnių galinčių įtakoti ligos eigą. Literatūros duomenys apie klinikinę BRCA1/2 genų reikšmę yra kontroversiški – nuo visiškai bereikšmio iki ženkliai teigiamo poveikio ligos eigai prognoziniu požiūriu.. Mūsų tyrėjų grupės atlikto tyrimo tikslas buvo nustatyti BRCA1/2 genų mutacijų dažnį ir jų įvairovę tarp pacienčių, sergančių išplitusiu kiaušidžių vėžiu, ir įvertinti šių mutacijų įtaką berecidyviam ir bendrajam išgyvenamumui. Mes nustatėme , kad tarp pacienčių sergančių išplitusių epiteliniu kiaušidžių vėžiu buvo net 51,4 proc. BRCA 1/2 mutacijų genuose turinčių pacienčių. 98,2 proc. šių pacienčių sirgo serozine papiline adenokarcinoma. Šios histologinės formos kiaušidžių vėžio buvo ženkliai daugiau mutuotų BRCA1/2 genų pacienčių grupėje nei tarp pacienčių be mutacijų (p-0,029). Tyrimo metu nustatėme dažniausiai sutinkamą arba bendro protėvio BRCA 1 4035 delA mutaciją bei taip kad statistiškai reikšmingos įtakos sergančiųjų išplitusiu kiaušidžių vėžiu berecidyviam išgyvenamumui turi pacienčių amžius (p=0,005), BRCA1/2 genų mutacijos(p=0,049) bei operacijos apimtis (p<0,0001), o bendrajam išgyvenamumui – tik operacijos... [toliau žr. visą tekstą]