Ovarian cancer: Status of homologous recombination pathway as a predictor of drug response

The Scarface Score: Deciphering Response to DNA Damage Agents in High-Grade Serous Ovarian Cancer-A GEICO Study

Genomic Instability (GI) is a transversal phenomenon shared by several tumor types that provide both prognostic and predictive information. In the context of high-grade serous ovarian cancer (HGSOC), response to DNA-damaging agents such as platinum-based and poly(ADP-ribose) polymerase inhibitors (PARPi) has been closely linked to deficiencies in the DNA repair machinery by homologous recombination repair (HRR) and GI. In this study, we have developed the Scarface score, an integrative algorithm based on genomic and transcriptomic data obtained from the NGS analysis of a prospective GEICO cohort of 190 formalin-fixed paraffin-embedded (FFPE) tumor samples from patients diagnosed with HGSOC with a median follow up of 31.03 months (5.87-159.27 months). In the first step, three single-source models, including the SNP-based model (accuracy = 0.8077), analyzing 8 SNPs distributed along the genome; the GI-based model (accuracy = 0.9038) interrogating 28 parameters of GI; and the HTG-based model (accuracy = 0.8077), evaluating the expression of 7 genes related with tumor biology; were proved to predict response. Then, an ensemble model called the Scarface score was found to predict response to DNA-damaging agents with an accuracy of 0.9615 and a kappa index of 0.9128 (p < 0.0001). The Scarface Score approaches the routine establishment of GI in the clinical setting, enabling its incorporation as a predictive and prognostic tool in the management of HGSOC.

DPADM: a novel algorithm for detecting drug-pathway associations based on high-throughput transcriptional response to compounds

Pathway genes functionally participate in the same biological process. They typically act cooperatively, and none is considered dispensable. The dominant paradigm in drug discovery is the one-to-one strategy, which aims to find the most sensitive drug to act on an individual target. However, many complex diseases, such as cancer, are caused by dysfunction among multiple-gene pathways, not just one. Therefore, identifying pathway genes that are responsive to synthetic compounds in a global physiological environment may be more effective in drug discovery. The high redundancy of crosstalk between biological pathways, though, hints that the covariance matrix, which only connects genes with strong marginal correlations, may miss higher-level interactions, such as group interactions. We herein report the development of DPADM-a Drug-Pathway association Detection Model that infers pathways responsive to specific drugs. This model elucidates higher-level gene-gene interactions by evaluating the conditional dependencies between genes under different drug treatments. The advantage of the proposed method is demonstrated using simulation studies by comparing with another two methods. We applied this model to the Connectivity Map data set (CMap), and demonstrated that DPADM is able to identify many drug-pathway associations, such as mitoxantrone (MTX)- PI3K/AKT association, which targets the topological conditions of DNA transcription. Surprisingly, apart from identifying pathways corresponding to specific drugs, our methodology also revealed new drug-related pathways with functions similarly to those of seed genes.

Ferrocifen stealth LNCs and conventional chemotherapy: A promising combination against multidrug-resistant ovarian adenocarcinoma

Ovarian cancer is one of the deadliest epithelial malignancies in women, owing to the multidrug resistance that restricts the success of conventional chemotherapy, carboplatin and paclitaxel. High grade serous ovarian carcinoma can be classified into two subtypes, the chemosensitive High OXPHOS and the Low OXPHOS tumour, less sensitive to chemotherapy. This difference of treatment efficacy could be explained by the redox status of these tumours, High OXPHOS exhibiting a chronic oxidative stress and an accumulation of reactive oxygen species. Ferrocifens, bio-organometallic compounds, are believed to be ROS producers with a good cytotoxicity on ovarian cancer cell lines. The aim of this study was to evaluate the in vivo efficacy of ferrocifen stealth lipid nanocapsules on High and Low OXPHOS ovarian Patient-Derived Xenograft models, alone or in combination to standard chemotherapy. Accordingly, two ferrocifens, P53 and P722, were encapsulated in stealth LNCs. The treatment by stealth P722-LNCs in combination with standard chemotherapy induced, with a concentration eight time lower than in stealth P53-LNCs, similar tumour reduction on a Low OXPHOS model, allowing us to conclude that P722 could be a leading ferrocifen to treat ovarian cancer. This combination of treatments may represent a promising synergistic approach to treat resistant ovarian adenocarcinoma.

The histone methyltransferase SUVR2 promotes DSB repair via chromatin remodeling and liquid-liquid phase separation

Maintaining genomic integrity and stability is particularly important for stem cells, which are at the top of the cell lineage origin. Here, we discovered that the plant-specific histone methyltransferase SUVR2 maintains the genome integrity of the root tip stem cells through chromatin remodeling and liquid-liquid phase separation (LLPS) when facing DNA double-strand breaks (DSBs). The histone methyltransferase SUVR2 (MtSUVR2) has histone methyltransferase activity and catalyzes the conversion of histone H3 lysine 9 monomethylation (H3K9me1) to H3K9me2/3 in vitro and in Medicago truncatula. Under DNA damage, the proportion of heterochromatin decreased and the level of DSB damage marker γ-H2AX increased in suvr2 mutants, indicating that MtSUVR2 promotes the compaction of the chromatin structure through H3K9 methylation modification to protect DNA from damage. Interestingly, MtSUVR2 was induced by DSBs to phase separate and form droplets to localize at the damage sites, and this was confirmed by immunofluorescence and fluorescence recovery after photobleaching experiments. The IDR1 and low-complexity domain regions of MtSUVR2 determined its phase separation in the nucleus, whereas the IDR2 region determined the interaction with the homologous recombinase MtRAD51. Furthermore, we found that MtSUVR2 drove the phase separation of MtRAD51 to form "DNA repair bodies," which could enhance the stability of MtRAD51 proteins to facilitate error-free homologous recombination repair of stem cells. Taken together, our study reveals that chromatin remodeling-associated proteins participate in DNA repair through LLPS.

Patient Experience with a Gynecologic Oncology-Initiated Genetic Testing Model for Women with Tubo-Ovarian Cancer

Background: Up to 20% of women diagnosed with tubo-ovarian carcinoma carry a germline pathogenic variant in a cancer-predisposing gene (e.g., BRCA1/BRCA2). Identifying these variants can help to inform eligibility for therapies, guide surveillance and prevention of new primary cancers, and assess risk to family members. The Gynecologic Oncology-Initiated Genetic Testing Model (GOIGT) was initiated at the McGill University Health Centre (MUHC) to streamline universal germline genetic testing for this population, while addressing the limited resources in the public healthcare system. This study aimed to evaluate the patient experience of participating in this model. Methods: Study participants were patients diagnosed with high-grade non-mucinous epithelial tubo-ovarian cancer who underwent genetic testing through the GOIGT model between 1 January 2017 and 31 December 2020. Eligible participants completed the retrospective questionnaires at least one month after result disclosure. Results: A total of 126 patients were tested through the GOIGT model during the study period, of which 56 were invited to participate. Thirty-four participants returned the study questionnaire. Overall, participants did not report decision regret following the genetic testing and were satisfied with the GOIGT model. Participants reported low levels of uncertainty and distress related to the implications of their test results for themselves and their family members. Conclusions: The results of this study support the continued implementation of mainstreamed genetic testing models for women with high-grade non-mucinous tubo-ovarian cancer. Further studies are required to compare experiences for patients with different genetic test results.

Integrated clinical characteristics and omics analysis identifies a ferroptosis and iron-metabolism-related lncRNA signature for predicting prognosis and therapeutic responses in ovarian cancer

Background

Ferroptosis and iron-metabolism are regulated by Long non-coding RNAs (lncRNAs) in ovarian cancer (OC). Therefore, a comprehensive analysis of ferroptosis and iron-metabolism related lncRNAs (FIRLs) in OC is crucial for proposing therapeutic strategies and survival prediction.

Methods

In multi-omics data from OC patients, FIRLs were identified by calculating Pearson correlation coefficients with ferroptosis and iron-metabolism related genes (FIRGs). Cox-Lasso regression analysis was performed on the FIRLs to screen further the lncRNAs participating in FIRLs signature. In addition, all patients were divided into two robust risk subtypes using the FIRLs signature. Receiver operator characteristic (ROC) curve, Kaplan–Meier analysis, decision curve analysis (DCA), Cox regression analysis and calibration curve were used to confirm the clinical benefits of FIRLs signature. Meanwhile, two nomograms were constructed to facilitate clinical application. Moreover, the potential biological functions of the signature were investigated by genes function annotation. Finally, immune microenvironment, chemotherapeutic sensitivity, and the response of PARP inhibitors were compared in different risk groups using diversiform bioinformatics algorithms.

Results

The raw data were randomized into a training set (n = 264) and a testing set (n = 110). According to Pearson coefficients between FIRGs and lncRNAs, 1075 FIRLs were screened for univariate Cox regression analysis, and then LASSO regression analysis was used to construct 8-FIRLs signature. It is worth mentioning that a variety of analytical methods indicated excellent predictive performance for overall survival (OS) of FIRLs signature (p < 0.05). The multivariate Cox regression analysis showed that FIRLs signature was an independent prognostic factor for OS (p < 0.05). Moreover, significant differences in the abundance of immune cells, immune-related pathways, and drug response were excavated in different risk subtypes (p < 0.05).

Conclusion

The FIRLs signature can independently predict overall survival and therapeutic effect in OC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-022-00944-y.

Chemotherapy toxicity and activity in patients with pancreatic ductal adenocarcinoma and germline BRCA1-2 pathogenic variants (gBRCA1-2pv): a multicenter survey

BACKGROUND

Germline BRCA1-2 pathogenic variants (gBRCA1-2pv)-related pancreatic ductal adenocarcinoma (PDAC) showed increased sensitivity to DNA cross-linking agents. This study aimed at exploring safety profile, dose intensity, and activity of different chemotherapy regimens in this setting.

PATIENTS AND METHODS

gBRCA1-2pv PDAC patients of any age and clinical tumor stage who completed a first course of chemotherapy were eligible. A descriptive analysis of chemotherapy toxicity, dose intensity, response, and survival outcomes was performed.

RESULTS

A total of 85 gBRCA1-2pv PDAC patients treated in 21 Italian centers between December 2008 and March 2021were enrolled. Seventy-four patients were assessable for toxicity and dose intensity, 83 for outcome. Dose intensity was as follows: nab-paclitaxel 72%, gemcitabine 76% (AG); cisplatin 75%, nab-paclitaxel 73%, capecitabine 73%, and gemcitabine 65% (PAXG); fluorouracil 35%, irinotecan 58%, and oxaliplatin 64% (FOLFIRINOX). When compared with the literature, grade 3-4 neutropenia, thrombocytopenia, and diarrhea were increased with PAXG, and unmodified with AG and FOLFIRINOX. RECIST responses were numerically higher with the three- (81%) or four-drug (73%) platinum-containing regimens that outperformed AG (41%) and oxaliplatin-based doublets (56%). Carbohydrate antigen 19.9 (CA19.9) reduction >89% at nadir was reported in two-third of metastatic patients treated with triplets and quadruplets, as opposed to 33% and 45% of patients receiving oxaliplatin-based doublets or AG, respectively. All patients receiving AG experienced disease progression, with a median progression-free survival (mPFS) of 6.4 months, while patients treated with platinum-containing triplets or quadruplets had an mPFS >10.8 months. Albeit still immature, data on overall survival seemed to parallel those on PFS.

CONCLUSIONS

Our data, as opposed to figures expected from the literature, highlighted that platinum-based regimens provoked an increased toxicity on proliferating cells, when dose intensity was maintained, or an as-expected toxicity, when dose intensity was reduced, while no change in toxicity and dose intensity was evident with AG. Furthermore, an apparently improved outcome of platinum-based triplets or quadruplets over other regimens was observed.

PARP-inhibitors in epithelial ovarian cancer: Actual positioning and future expectations

Poly-(ADP)-ribose polymerase inhibitors (PARPi) are a class of oral anticancer drugs first developed as "synthetically lethal" in cancers harboring BRCA1/BRCA2 inactivating mutations. In high-grade serous or endometrioid ovarian cancers (HGOC), PARPi demonstrated benefit as maintenance therapy in relapsing BRCA-mutated and non-mutated tumors. Recently, they extended their indications to frontline maintenance therapy. This review summarizes the current place of PARPi (i) as maintenance or single agent in recurrent disease and (ii) frontline maintenance with different settings. We reviewed the course of biomarker identification, the challenge of overcoming resistance to PARPi and future combinations with targeted therapies, including anti-angiogenic, immune checkpoint inhibitors and DNA damage response inhibitors.

The identification of six risk genes for ovarian cancer platinum response based on global network algorithm and verification analysis

Ovarian cancer is the most lethal gynaecological cancer, and resistance of platinum‐based chemotherapy is the main reason for treatment failure. The aim of the present study was to identify candidate genes involved in ovarian cancer platinum response by analysing genes from homologous recombination and Fanconi anaemia pathways. Associations between these two functional genes were explored in the study, and we performed a random walk algorithm based on reconstructed gene‐gene network, including protein‐protein interaction and co‐expression relations. Following the random walk, all genes were ranked and GSEA analysis showed that the biological functions focused primarily on autophagy, histone modification and gluconeogenesis. Based on three types of seed nodes, the top two genes were utilized as examples. We selected a total of six candidate genes (FANCA, FANCG, POLD1, KDM1A, BLM and BRCA1) for subsequent verification. The validation results of the six candidate genes have significance in three independent ovarian cancer data sets with platinum‐resistant and platinum‐sensitive information. To explore the correlation between biomarkers and clinical prognostic factors, we performed differential analysis and multivariate clinical subgroup analysis for six candidate genes at both mRNA and protein levels. And each of the six candidate genes and their neighbouring genes with a mutation rate greater than 10% were also analysed by network construction and functional enrichment analysis. In the meanwhile, the survival analysis for platinum‐treated patients was performed in the current study. Finally, the RT‐qPCR assay was used to determine the performance of candidate genes in ovarian cancer platinum response. Taken together, this research demonstrated that comprehensive bioinformatics methods could help to understand the molecular mechanism of platinum response and provide new strategies for overcoming platinum resistance in ovarian cancer treatment.

BRCA testing in women with high-grade serous ovarian cancer: gynecologic oncologist-initiated testing compared with genetics referral

OBJECTIVE

Up to 15% of patients with high-grade serous ovarian, tubal, or peritoneal carcinoma harbor a mutation in BRCA genes. Early notion of mutation status may facilitate counseling, predict prognosis, and increase access to Parp-inhibitors. The aim of this study was to examine the rate of germline genetic testing in a retrospective cohort of women with high-grade serous ovarian, tubal, or peritoneal carcinoma to determine if a new pilot project of gynecologic oncologist-initiated genetic testing improved the rate of testing, after 1 year of implementation.

METHODS

Gynecologic oncology-initiated genetic testing was implemented at a single university hospital center with input and collaboration from gynecological oncologists, nurses, and genetic counselors. All patients diagnosed with high-grade serous ovarian, tubal, or peritoneal carcinoma after August 2017 were offered gynecologic oncologist- initiated genetic testing for a panel of 13 hereditary breast and ovarian cancer susceptibility genes. Data from this group was then compared with a historic cohort of patients who received traditional genetic counseling between January 2014 and August 2017 (control group). Patients that had genetic testing through a clinical trial were excluded. The primary outcome was the uptake of genetic testing in both groups. Secondary outcomes included difference in time from diagnosis to genetic result between both cohorts. Data was analyzed using SPSS 25.0 and medians (ranges) were reported.

RESULTS

A total of 152 women with high-grade serous ovarian, tubal, or peritoneal carcinoma were included in this study. Between January 2014 to July 2017 there were 108 patients with high-grade serous ovarian, tubal, or peritoneal carcinoma, among which 50.9% (n=54) underwent genetic testing following referral to genetics. The prevalence of BRCA pathogenic variants was 25.9% (14/54): 9.2% (5/54) in BRCA1 and 16.7% (9/54) in BRCA2. The median time from diagnosis to genetics referral was 53 days (range; 3-751), and median time from diagnosis to test result disclosure was 186 days (range; 15-938). After 1 year of implementation of the gynecologic oncologist-initiated genetic testing model, among 44 women diagnosed with high-grade serous ovarian, tubal, or peritoneal carcinoma, 86.2% underwent genetic testing. The median time from diagnosis to result disclosure decreased to 58 days, representing a reduction of 128 days, or 4.27 months (P<0.001). Reasons for non-testing included refusal, death, and follow-up at another hospital. The prevalence of germline BRCA1/2 pathogenic variants was 21% (8/38).

CONCLUSION

Gynecologic oncologist-initiated genetic testing at the time of high-grade serous ovarian, tubal, or peritoneal carcinoma diagnosis leads to increased uptake and decreased delays in testing compared with referral for traditional genetic counseling.

HIST1H2BB and MAGI2 Methylation and Somatic Mutations as Precision Medicine Biomarkers for Diagnosis and Prognosis of High-grade Serous Ovarian Cancer

Molecular alterations that contribute to long-term (LT) and short-term (ST) survival in ovarian high-grade serous carcinoma (HGSC) may be used as precision medicine biomarkers. DNA promoter methylation is an early event in tumorigenesis, which can be detected in blood and urine, making it a feasible companion biomarker to somatic mutations for early detection and targeted treatment workflows. We compared the methylation profile in 12 HGSC tissue samples to 30 fallopian tube epithelium samples, using the Infinium Human Methylation 450K Array. We also used 450K methylation arrays to compare methylation among HGSCs long-term survivors (more than 5 years) and short-term survivors (less than 3 years). We verified the array results using bisulfite sequencing and methylation-specific PCR (qMSP). in another cohort of HGSC patient samples (n = 35). Immunoblot and clonogenic assays after pharmacologic unmasking show that HIST1H2BB and MAGI2 promoter methylation downregulates mRNA expression levels in ovarian cancer cells. We then used qMSP in paired tissue, ascites, plasma/serum, vaginal swabs, and urine from a third cohort of patients with HGSC cancer (n = 85) to test the clinical potential of HIST1H2BB and MAGI2 in precision medicine workflows. We also performed next-generation exome sequencing of 50 frequently mutated in human cancer genes, using the Ion AmpliSeqCancer Hotspot Panel, to show that the somatic mutation profile found in tissue and plasma can be quantified in paired urine samples from patients with HGSC. Our results suggest that HIST1H2BB and MAGI2 have growth-suppressing roles and can be used as HGSC precision medicine biomarkers.

Changes in DNA Damage Response Markers with Treatment in Advanced Ovarian Cancer

Ovarian cancer (OC) is sensitive to upfront chemotherapy, which is likely attributable to defects in DNA damage repair (DDR). Unfortunately, patients relapse and the evolution of DDR competency are poorly described. We examined the expression of proposed effectors in homologous recombination (HR: RAD51, ATM, FANCD2), error-prone non-homologous end-joining (NHEJ: 53BP1), and base excision repair pathways (BER: PAR and PARP1) in a cohort of sequential OC samples obtained at diagnosis, after neoadjuvant chemotherapy (NACT), and/or at relapse from a total of 147 patients. Immunohistochemical (IHC) expression was quantified using the H-score (0-300), where H ≤ 10 defined negativity. Before NACT, a significant number of cases lacked the expression of some effectors: 60%, 60%, and 24% were PAR-, FANCD2-, or RAD51-negative, with a reassuringly similar proportion of negative biomarkers after NACT. In multivariate analysis, there was a poorer progression-free survival (PFS) and overall survival (OS) for cases with competent HR at diagnosis (PRE-NACT 53BP1-/RAD51+, hazard ratio (HR) 3.13, p = 0.009 and HR 2.78, p = 0.024) and after NACT (POST-NACT FANCD2+/RAD51+ HR 1.89, p = 0.05 and HR 2.38, p = 0.02; POST-NACT PARP-1+/RAD51+ HR 1.79, p = 0.038 and HR 2.04, p = 0.034), reflecting proficient DNA repair. Overall, HR-competent tumors appeared to have a dismal prognosis in comparison with tumors utilizing NHEJ, as assessed either at baseline or post-NACT. Accurate knowledge of the HR status during treatment is clinically important for the efficient timing of platinum-based and targeted therapies with poly(ADP-ribose) polymerase inhibitors (PARPi).

Homologous Recombination Repair Deficiency and the Immune Response in Breast Cancer: A Literature Review

The success of cancer immunotherapy with immune checkpoint blockade (ICB) has demonstrated the importance of targeting a preexisting immune response in a broad spectrum of tumors. This is particularly novel and relevant for less immunogenic tumors, such as breast cancer (BC), where the efficacy of ICB was more evident in the triple-negative (TNBC) subtype, in earlier stages, and in association with chemotherapy. Tumors harboring homologous recombination DNA repair (HRR) deficiency (HRD) are supposed to have a higher number of mutations, hence a higher tumor mutational burden, which could potentially make them more sensitive to immunotherapy. However, the mechanisms involved in ICB sensitivity and patient selection are still yet to be defined in BC: whether the innate system could play a role and how the adaptive immunity could be linked with HRR pathways are the two key points of debate that we will discuss in this article. The aim of this review was to close the loop between what was found in clinical trial results so far, go back to laboratory theory and preclinical results and point out what needs to be clarified from now on.

BRCA1/BRCA2 germline mutations and chemotherapy-related hematological toxicity in breast cancer patients

PURPOSE

BRCA1 and BRCA2 proteins are central to DNA repair process through homologous recombination. We hypothesize that BRCA1/BRCA2 mutation carriers may exhibit increased hematological toxicity when receiving genotoxic chemotherapy.

METHODS

We included women with primary breast cancers screened for BRCA1/BRCA2 germline mutations and treated with (neo)adjuvant chemotherapy in Geneva (Swiss cohort). The primary endpoint was the incidence of febrile neutropenia following the first chemotherapy cycle (C1). Secondary endpoints were the incidence of grade 3-4 neutropenia, grade 4 neutropenia and hospitalization during C1, G-CSF use and chemotherapy dose reduction during the entire chemotherapy regimen. Long-term toxicities (hematological, cardiac and neuropathy) were assessed in the Swiss cohort and a second cohort of patients from Lyon (French cohort).

RESULTS

Overall, 221 patients were assessed for acute hematological toxicity, including 23 BRCA1 and 22 BRCA2 carriers. Following the C1, febrile neutropenia had an incidence of 35% (p = 0.002), 14% (p = 0.562) and 10% among BRCA1, BRCA2 and non-carriers, respectively. Grade 4 neutropenia was found in 57% of BRCA1 (p < 0.001), 14% of BRCA2 (p = 0.861) and 18% of non-carriers. G-CSF support was necessary in 86% of BRCA1 (p = 0.005), 64% of BRCA2 (p = 0.285) and 51% of non-carriers. For long-term toxicity analysis, 898 patients were included (167 BRCA1-, 91 BRCA2- and 640 non-carriers). There was no difference between the 3 groups.

CONCLUSIONS

BRCA1 germline mutations is associated with greater acute hematological toxicity in breast cancer patients. These observations could have implication for primary prophylaxis with G-CSF.

Clinical importance of FANCD2, BRIP1, BRCA1, BRCA2 and FANCF expression in ovarian carcinomas

OBJECTIVE

DNA repair pathways are potential targets of molecular therapy in cancer patients. The FANCD2, BRIP1, BRCA1/2, and FANCF genes are involved in homologous recombination DNA repair, which implicates their possible role in cell response to DNA-damaging agents. We evaluated a clinical significance of pre-treatment expression of these genes at mRNA level in 99 primary, advanced-stage ovarian carcinomas from patients, who later received taxane-platinum (TP) or platinum-cyclophosphamide (PC) treatment.

METHODS

Gene expression was determined with the use of Real-Time PCR. The BRCA2 and BRIP1 gene sequence was investigated with the use of SSCP, dHPLC, and PCR-sequencing.

RESULTS

Increased FANCD2 expression occurred to be a negative prognostic factor for all patients (PC+TP:HR 3.85, p = 0.0003 for the risk of recurrence; HR 1.96, p = 0.02 for the risk of death), and this association was even stronger in the TP-treated group (HR 6.7, p = 0.0002 and HR 2.33, p = 0.01, respectively). Elevated BRIP1 expression was the only unfavorable molecular factor in the PC-treated patients (HR 8.37, p = 0.02 for the risk of recurrence). Additionally, an increased FANCD2 and BRCA1/2 expression levels were associated with poor ovarian cancer outcome in either TP53-positive or -negative subgroups of the TP-treated patients, however these groups were small. Sequence analysis identified one protein truncating variant (1/99) in BRCA2 and no mutations (0/56) in BRIP1.

CONCLUSIONS

Our study shows for the first time that FANCD2 overexpression is a strong negative prognostic factor in ovarian cancer, particularly in patients treated with TP regimen. Moreover, increased mRNA level of the BRIP1 is a negative prognostic factor in the PC-treated patients. Next, changes in the BRCA2 and BRIP1 genes are rare and together with other analyzed FA genes considered as homologous recombination deficiency may not affect the expression level of analyzed genes.

Targeted composite value-based endpoints in platinum-sensitive recurrent ovarian cancer

OBJECTIVES

FDA-approved treatments for platinum-sensitive recurrent ovarian cancer (PSROC) include bevacizumab and PARP inhibitors (PARPi); clinical decisions regarding therapy must be made prior to initiating chemotherapy. Using the American Society of Clinical Oncology (ASCO) and European Society of Medical Oncology (ESMO) value frameworks, we assessed relative values of concurrent/maintenance biologic therapies in PSROC.

METHODS

Value scores were calculated for key maintenance therapies based on randomized controlled trials: bevacizumab (OCEANS, GOG 213); olaparib (Study 19, SOLO2); niraparib (NOVA); rucaparib (ARIEL3). Personalized value scorecards were constructed for patients with germline/somatic-BRCA mutations, homologous recombination deficiency (HRD), and wild-type BRCA (wBRCA). ASCO value scores assess clinical benefit, toxicity, long-term survival, symptom palliation, treatment-free interval, and quality of life (QOL). ESMO value scores assess clinical benefit, toxicity, and QOL.

RESULTS

ASCO scores were highest for maintenance PARPi in germline/somatic-BRCA mutation cohorts: olaparib (SOLO2) = 47, (Study 19) = 62; niraparib = 50; rucaparib = 54. HRD cohorts had slightly lower scores: niraparib = 46; rucaparib = 37. wBRCA cohorts had the lowest scores: niraparib = 26; rucaparib = 26; and olaparib (Study 19) = 32, as did patients receiving bevacizumab (OCEANS) = 35, (GOG 213) = 26. ESMO scores demonstrated high-value for maintenance PARPi in germline/somatic-BRCA mutation cohorts and low-value for bevacizumab and PARPi in wBRCA cohorts.

CONCLUSIONS

The value of maintenance PARPi therapy depends heavily on BRCA status, with the highest value scores in germline/somatic-BRCA mutation cohorts. Personalized value scorecards provide a visual aid to assess the harm-benefit balance of maintenance PARPi for PSROC.

PML-Regulated Mitochondrial Metabolism Enhances Chemosensitivity in Human Ovarian Cancers

High-grade serous ovarian cancer (HGSOC) remains an unmet medical challenge. Here, we unravel an unanticipated metabolic heterogeneity in HGSOC. By combining proteomic, metabolomic, and bioergenetic analyses, we identify two molecular subgroups, low- and high-OXPHOS. While low-OXPHOS exhibit a glycolytic metabolism, high-OXPHOS HGSOCs rely on oxidative phosphorylation, supported by glutamine and fatty acid oxidation, and show chronic oxidative stress. We identify an important role for the PML-PGC-1α axis in the metabolic features of high-OXPHOS HGSOC. In high-OXPHOS tumors, chronic oxidative stress promotes aggregation of PML-nuclear bodies, resulting in activation of the transcriptional co-activator PGC-1α. Active PGC-1α increases synthesis of electron transport chain complexes, thereby promoting mitochondrial respiration. Importantly, high-OXPHOS HGSOCs exhibit increased response to conventional chemotherapies, in which increased oxidative stress, PML, and potentially ferroptosis play key functions. Collectively, our data establish a stress-mediated PML-PGC-1α-dependent mechanism that promotes OXPHOS metabolism and chemosensitivity in ovarian cancer.

Discovery of a novel DNA polymerase inhibitor and characterization of its antiproliferative properties

Chromosomal duplication is targeted by various chemotherapeutic agents for the treatment of cancer. However, there is no specific inhibitor of DNA polymerases that is viable for cancer management. Through structure-based in silico screening of the ZINC database, we identified a specific inhibitor of DNA polymerase δ. The discovered inhibitor, Zelpolib, is projected to bind to the active site of Pol δ when it is actively engaged in DNA replication through interactions with DNA template and primer. Zelpolib shows robust inhibition of Pol δ activity in reconstituted DNA replication assays. Under cellular conditions, Zelpolib is taken up readily by cancer cells and inhibits DNA replication in assays to assess global DNA synthesis or single-molecule bases by DNA fiber fluorography. In addition, we show that Zelpolib displays superior antiproliferative properties to methotrexate, 5-flourouracil, and cisplatin in triple-negative breast cancer cell line, pancreatic cancer cell line and platinum-resistant pancreatic cancer cell line. Pol δ is not only involved in DNA replication, it is also a key component in many DNA repair pathways. Pol δ is the key enzyme responsible for D-loop extension during homologous recombination. Indeed, Zelpolib shows robust inhibition of homologous recombination repair of DNA double-strand breaks and induces "BRCAness" in HR-proficient cancer cells and enhances their sensitivity to PARP inhibitors.

Targeting homologous repair deficiency in breast and ovarian cancers: Biological pathways, preclinical and clinical data

Mutation or epigenetic silencing of homologous recombination (HR) repair genes is characteristic of a growing proportion of triple-negative breast cancers (TNBCs) and high-grade serous ovarian carcinomas. Defects in HR lead to genome instability, allowing cells to acquire the multiple genetic alterations essential for cancer development. However, this deficiency can also be exploited by using DNA damaging agents or by targeting compensatory repair pathways. A noteworthy example is treatment of TNBC and epithelial ovarian cancer harboring BRCA1/2 germline mutations using platinum salts and/or PARP inhibitors. Dramatic responses to PARP inhibitors may support a wider use in the HR-deficient population beyond those with mutated germline BRCA1 and 2. In this review, we discuss HR deficiency hallmarks as predictive biomarkers for platinum salt and PARP inhibitor sensitivity for selecting patients affected by TNBC or epithelial ovarian cancer who could benefit from these therapeutic options.

Landscape of genomic alterations in high-grade serous ovarian cancer from exceptional long- and short-term survivors

BACKGROUND

Patients diagnosed with high-grade serous ovarian cancer (HGSOC) who received initial debulking surgery followed by platinum-based chemotherapy can experience highly variable clinical responses. A small percentage of women experience exceptional long-term survival (long term (LT), 10+ years), while others develop primary resistance to therapy and succumb to disease in less than 2 years (short term (ST)). To improve clinical management of HGSOC, there is a need to better characterize clinical and molecular profiles to identify factors that underpin these disparate survival responses.

METHODS

To identify clinical and tumor molecular biomarkers associated with exceptional clinical response or resistance, we conducted an integrated clinical, exome, and transcriptome analysis of 41 primary tumors from LT (n = 20) and ST (n = 21) HGSOC patients.

RESULTS

Younger age at diagnosis, no residual disease post debulking surgery and low CA125 levels following surgery and chemotherapy were clinical characteristics of LT. Tumors from LT survivors had increased somatic mutation burden (median 1.62 vs. 1.22 non-synonymous mutations/Mbp), frequent BRCA1/2 biallelic inactivation through mutation and loss of heterozygosity, and enrichment of activated CD4+, CD8+ T cells, and effector memory CD4+ T cells. Characteristics of ST survival included focal copy number gain of CCNE1, lack of BRCA mutation signature, low homologous recombination deficiency scores, and the presence of ESR1-CCDC170 gene fusion.

CONCLUSIONS

Our findings suggest that exceptional long- or short-term survival is determined by a concert of clinical, molecular, and microenvironment factors.

Landscape of genomic alterations in high-grade serous ovarian cancer from exceptional long- and short-term survivors

Background

Patients diagnosed with high-grade serous ovarian cancer (HGSOC) who received initial debulking surgery followed by platinum-based chemotherapy can experience highly variable clinical responses. A small percentage of women experience exceptional long-term survival (long term (LT), 10+ years), while others develop primary resistance to therapy and succumb to disease in less than 2 years (short term (ST)). To improve clinical management of HGSOC, there is a need to better characterize clinical and molecular profiles to identify factors that underpin these disparate survival responses.

Methods

To identify clinical and tumor molecular biomarkers associated with exceptional clinical response or resistance, we conducted an integrated clinical, exome, and transcriptome analysis of 41 primary tumors from LT (n = 20) and ST (n = 21) HGSOC patients.

Results

Younger age at diagnosis, no residual disease post debulking surgery and low CA125 levels following surgery and chemotherapy were clinical characteristics of LT. Tumors from LT survivors had increased somatic mutation burden (median 1.62 vs. 1.22 non-synonymous mutations/Mbp), frequent BRCA1/2 biallelic inactivation through mutation and loss of heterozygosity, and enrichment of activated CD4+, CD8+ T cells, and effector memory CD4+ T cells. Characteristics of ST survival included focal copy number gain of CCNE1, lack of BRCA mutation signature, low homologous recombination deficiency scores, and the presence of ESR1-CCDC170 gene fusion.

Conclusions

Our findings suggest that exceptional long- or short-term survival is determined by a concert of clinical, molecular, and microenvironment factors.

Electronic supplementary material

The online version of this article (10.1186/s13073-018-0590-x) contains supplementary material, which is available to authorized users.

Landscape of genomic alterations in high-grade serous ovarian cancer from exceptional long- and short-term survivors

BACKGROUND

Patients diagnosed with high-grade serous ovarian cancer (HGSOC) who received initial debulking surgery followed by platinum-based chemotherapy can experience highly variable clinical responses. A small percentage of women experience exceptional long-term survival (long term (LT), 10+ years), while others develop primary resistance to therapy and succumb to disease in less than 2 years (short term (ST)). To improve clinical management of HGSOC, there is a need to better characterize clinical and molecular profiles to identify factors that underpin these disparate survival responses.

METHODS

To identify clinical and tumor molecular biomarkers associated with exceptional clinical response or resistance, we conducted an integrated clinical, exome, and transcriptome analysis of 41 primary tumors from LT (n = 20) and ST (n = 21) HGSOC patients.

RESULTS

Younger age at diagnosis, no residual disease post debulking surgery and low CA125 levels following surgery and chemotherapy were clinical characteristics of LT. Tumors from LT survivors had increased somatic mutation burden (median 1.62 vs. 1.22 non-synonymous mutations/Mbp), frequent BRCA1/2 biallelic inactivation through mutation and loss of heterozygosity, and enrichment of activated CD4+, CD8+ T cells, and effector memory CD4+ T cells. Characteristics of ST survival included focal copy number gain of CCNE1, lack of BRCA mutation signature, low homologous recombination deficiency scores, and the presence of ESR1-CCDC170 gene fusion.

CONCLUSIONS

Our findings suggest that exceptional long- or short-term survival is determined by a concert of clinical, molecular, and microenvironment factors.

Bayesian inference of hub nodes across multiple networks

Hub nodes within biological networks play a pivotal role in determining phenotypes and disease outcomes. In the multiple network setting, we are interested in understanding network similarities and differences across different experimental conditions or subtypes of disease. The majority of proposed approaches for joint modeling of multiple networks focus on the sharing of edges across graphs. Rather than assuming the network similarities are driven by individual edges, we instead focus on the presence of common hub nodes, which are more likely to be preserved across settings. Specifically, we formulate a Bayesian approach to the problem of multiple network inference which allows direct inference on shared and differential hub nodes. The proposed method not only allows a more intuitive interpretation of the resulting networks and clearer guidance on potential targets for treatment, but also improves power for identifying the edges of highly connected nodes. Through simulations, we demonstrate the utility of our method and compare its performance to current popular methods that do not borrow information regarding hub nodes across networks. We illustrate the applicability of our method to inference of co-expression networks from The Cancer Genome Atlas ovarian carcinoma dataset.

The Challenge of Evaluating Adnexal Masses in Patients With Breast Cancer

This narrative literature review addresses the problem of an adnexal mass discovered during the course of breast cancer (BC) care, which may represent a benign condition, a metastatic process, or a primary ovarian cancer (OC), clinical scenarios associated with distinct physiopathology and prognosis. Furthermore, the coexistence of BC and OC in the same patient may be owing to a hereditary disorder, deserving specific management strategies and counseling. The initial detection and evaluation of an adnexal mass in a patient with BC requires a high index of suspicion, and the initial workup should include a thorough medical history and physical examination, measurement of tumor markers, complete blood count, and imaging tests. Transvaginal ultrasonography remains the standard tool, and findings suggestive of malignancy include bilateral tumors, thick septations, predominance of a solid component, Doppler flow to the solid component, and ascites. From the pathology point of view, features that are suggestive of metastatic disease include bilaterality, mild ovarian enlargement, vascular emboli, no omental deposits, and the absence of transition from benign to malignant epithelium. Although there is a considerable overlap in OC and BC immunohistochemical profiles, BC usually stain positive for GCDFP-15 and negative for vimentine, PAX8, and WT1, and OC often stain positive for CK7, PAX8, WT1, and to mesothelin. Genetic counselling should always be indicated in this clinical scenario. In conclusion, diagnostic spectrum of an ovarian mass in a patient with BC is broad, and a systematic multi-professional strategy is necessary to conduct these challenging cases.

Clinical importance of the EMSY gene expression and polymorphisms in ovarian cancer

EMSY, a BRCA2–associated protein, is amplified and overexpressed in various sporadic cancers. This is the first study assessing the clinical impact of its expression and polymorphisms on ovarian cancer (OvCa) outcome in the context of the chemotherapy regimen used. In 134 frozen OvCa samples, we assessed EMSY mRNA expression with Reverse Transcription-quantitative PCR, and also investigated the EMSY gene sequence using SSCP and/or PCR-sequencing. Clinical relevance of changes in EMSY mRNA expression and DNA sequence was evaluated in two subgroups treated with either taxane/platinum (TP, n=102) or platinum/cyclophosphamide (PC, n=32). High EMSY expression negatively affected overall survival (OS), disease-free survival (DFS) and sensitivity to treatment (PS) in the TP-treated subgroup (p-values: 0.001, 0.002 and 0.010, respectively). Accordingly, our OvCa cell line studies showed that the EMSY gene knockdown sensitized A2780 and IGROV1 cells to paclitaxel. Interestingly, EMSY mRNA expression in surviving cells was similar as in the control cells. Additionally, we identified 24 sequence alterations in the EMSY gene, including the previously undescribed: c.720G>C, p.(Lys240Asn); c.1860G>A, p.(Lys620Lys); c.246-76A>G; c.421+68A>C. In the PC-treated subgroup, a heterozygous genotype comprising five SNPs (rs4300410, rs3814711, rs4245443, rs2508740, rs2513523) negatively correlated with OS (p-value=0.009). The same SNPs exhibited adverse borderline associations with PS in the TP-treated subgroup. This is the first study providing evidence that high EMSY mRNA expression is a negative prognostic and predictive factor in OvCa patients treated with TP, and that the clinical outcome may hinge on certain SNPs in the EMSY gene as well.

Impact of BRCA mutations on outcomes among patients with serous endometrial cancer

OBJECTIVE

To compare the outcome of patients with uterine papillary serous cancer (UPSC) carrying a BRCA mutation with that of patients with UPSC who are BRCA wild-type.

METHODS

The present retrospective, multicenter cohort study included women with UPSC who were diagnosed between January 1, 1993, and December 31, 2014, and were tested for the BRCA mutation at three Israeli medical centers. Data were collected from the medical records, and patient and tumor characteristics and disease outcomes were compared between BRCA mutation carriers and noncarriers. The primary outcome was overall survival.

RESULTS

In total, 14 BRCA mutation carriers and 50 noncarriers were included. Both groups had similar treatment modalities (P=0.530). A non-significant trend toward BRCA mutation carriers being diagnosed more frequently at an advanced stage compared with noncarriers was observed (P=0.090). Median overall survival (25 vs 37 months; P=0.442), progression-free survival (37 vs 29 months; P=0.536), and disease-specific survival (60 vs 39 months; P=0.316) were similar between the carrier and noncarrier groups.

CONCLUSIONS

Although not significant, BRCA mutation carriers tended to have more advanced disease at diagnosis. However, the survival was similar irrespective of the BRCA status in this small group. Further research is needed to confirm these findings in a larger cohort.

[Recommendations for biomarker testing in epithelial ovarian cancer. A national consensus statement by the Spanish Society of Pathology and the Spanish Society of Medical Oncology]

Advances in the understanding of the histological and molecular characteristics of ovarian cancer now allow 5subtypes to be identified, leading to a more refined therapeutic approach and improved clinical trials. Each of the subtypes has specific histological features and a particular biomarker expression, as well as mutations in different genes, some of which have prognostic and predictive value. CA125 and HE4 are examples of ovarian cancer biomarkers used in diagnosis and follow-up. Currently, somatic or germinal mutations on BRCA1 and BRCA2 genes are the most important biomarkers in epithelial ovarian cancer, having prognostic and predictive value. In this article, a group of experts from the Spanish Society of Medical Oncology and the Spanish Society of Pathology review the histological and molecular characteristics of the 5subtypes of ovarian cancer and describe the most useful biomarkers and mutations for diagnosis, screening and tailored treatment strategy.

Rucaparib: An emerging parp inhibitor for treatment of recurrent ovarian cancer

Recently, Poly-ADP-Ribose Polymerase (PARP) inhibitors are one of the most intensively studied group of antiblastic agents for the management of recurrent ovarian cancer. Among this family, Olaparib was the first to be approved by European Medicines Agency as maintenance therapy post-response to platinum-based chemotherapy for recurrent ovarian cancer in women with deleterious BRCA1/2 mutation. Following that, the Food and Drug Administration (FDA) approved Olaparib monotherapy as fourth or later line of treatment in advanced ovarian cancer with deleterious germ-line BRCA1/2 mutation. On March 2017, Niraparib, was approved as maintenance treatment of patients with recurrent epithelial ovarian, who are in complete or partial response to platinum-based chemotherapy, independently of BRCA mutation. Rucaparib inhibits PARP-1, 2 and 3, PARP-4, -12, -15 and -16, as well as tankyrase 1 and 2. On December 2016, it was granted accelerated approval by the FDA, based on data from two multicenter, single arm, phase II trials that evaluated the efficacy of Rucaparib in patients with deleterious, germline and/or somatic BRCA mutation-associated, advanced OC, who have been treated with two or more lines of chemotherapy. The maximum tolerated dose reported was 600 mg twice a day administered orally. Phase III studies are currently ongoing to further validate the efficacy of Rucaparib in the treatment setting and explore its usefulness in a maintenance setting as well. The focus of our review is to report the most recent investigations and clinical progress regarding Rucaparib for treatment of recurrent ovarian cancer.

Knockdown of BRCA2 enhances cisplatin and cisplatin-induced autophagy in ovarian cancer cells

Clinical implications of the BRCA2 expression level on treatments of ovarian cancer are controversial. Here, we demonstrated that platinum-resistant cancer had a higher percentage of high BRCA2 level (87.5% vs 43.6%, P = 0.001), and that patients with a low BRCA2 level in cancer tissues had longer progression-free survival (with a median time of 28.0 vs 12.0 months, P < 0.001) and platinum-free duration (with a median time of 19.0 vs 5.0 months, P < 0.001) compared with those with a high BRCA2 level. In human ovarian cancer cell lines CAOV-3 and ES-2, cisplatin induced an upregulation of the RAD51 protein, which was inhibited after silencing BRCA2; silencing BRCA2 enhanced the action of cisplatin in vitro and in vivo Knockdown of BRCA2 promoted cisplatin-induced autophagy. Interestingly, the autophagy blocker chloroquine enhanced cisplatin in BRCA2-silenced cells accompanied by an increase in apoptotic cells, which did not occur in BRCA2-intact cells; chloroquine enhanced the efficacy of cisplatin against BRCA2-silenced CAOV-3 tumors in vivo, with an increase in LC3-II level in tumor tissues. Sensitization of cisplatin was also observed in BRCA2-silenced CAOV-3 cells after inhibiting ATG7, confirming that chloroquine modulated the sensitivity via the autophagy pathway. These data suggest that a low BRCA2 level can predict better platinum sensitivity and prognosis, and that the modulation of autophagy can be a chemosensitizer for certain cancers.

[Impairment of DNA damage response and cancer]

Maintaining the genetic integrity is a key process in cell viability and is enabled by a wide network of repair pathways. When this system is defective, it generates genomic instability and results in an accumulation of chromosomal aberrations and mutations that may be responsible for various clinical phenotypes, including susceptibility to develop cancer. Indeed, these defects can promote not only the initiation of cancer, but also allow the tumor cells to rapidly acquire mutations during their evolution. Several genes are involved in these damage repair systems and particular polymorphisms are predictive of the onset of cancer, the best described of them being BRCA. In addition to its impact on carcinogenesis, the DNA damage repair system is now considered as a therapeutic target of choice for cancer treatment, as monotherapy or in combination with other cytotoxic therapies, such as chemotherapies or radiotherapy. PARP inhibitors are nowadays the best known, but other agents are emerging in the field of clinical research. The enthusiasm in this area is coupled with promising results and a successful collaboration between clinicians and biologists would allow to optimize treatment plans in order to take full advantage of the DNA repair system modulation.

Location of Mutation in BRCA2 Gene and Survival in Patients with Ovarian Cancer

Purpose: BRCA2 plays a central role in homologous recombination by loading RAD51 on DNA breaks. The objective of this study is to determine whether the location of mutations in the RAD51-binding domain (RAD51-BD; exon 11) of BRCA2 gene affects the clinical outcome of ovarian cancer patients.Experimental Design: A study cohort of 353 women with ovarian cancer who underwent genetic germline testing for BRCA1 and BRCA2 genes was identified. Progression-free survival (PFS), platinum-free interval (PFI), and overall survival (OS) were analyzed. The Cancer Genome Atlas (TCGA) cohort of ovarian cancer (n = 316) was used as a validation cohort.Results: In the study cohort, 78 patients were carriers of germline mutations of BRCA2 After adjustment for FIGO stage and macroscopic residual disease, BRCA2 carriers with truncating mutations in the RAD51-BD have significantly prolonged 5-year PFS [58%; adjusted HR, 0.36; 95% confidence interval (CI), 0.20-0.64; P = 0.001] and prolonged PFI (29.7 vs. 15.5 months, P = 0.011), compared with noncarriers. BRCA2 carriers with mutations located in other domains of the gene do not have prolonged 5-year PFS (28%, adjusted HR, 0.67; 95% CI, 0.42-1.07; P = 0.094) or PFI (19 vs. 15.5 months, P = 0.146). In the TCGA cohort, only BRCA2 carriers harboring germline or somatic mutations in the RAD51-BD have prolonged 5-year PFS (46%; adjusted HR, 0.30; 95% CI, 0.13-0.68; P = 0.004) and 5-year OS (78%; adjusted HR, 0.09; 95% CI, 0.02-0.38; P = 0.001).Conclusions: Among ovarian cancer patients, BRCA2 carriers with mutations located in the RAD51-BD (exon 11) have prolonged PFS, PFI, and OS. Clin Cancer Res; 24(2); 326-33. ©2017 AACR.

Recommendations for biomarker testing in epithelial ovarian cancer: a National Consensus Statement by the Spanish Society of Pathology and the Spanish Society of Medical Oncology

Because of advances in the understanding of histological and molecular characteristics in ovarian cancer, it is now possible to recognize the existence of five subtypes, which in turn has allowed a more refined therapeutic approach and better design of clinical trials. Each of these five subtypes has specific histological features and a particular biomarker expression, as well as mutations in different genes, some of which have prognostic and predictive value. CA125 and HE4 are examples of ovarian cancer biomarkers used in the diagnosis and follow-up of these malignancies. Currently, somatic or germinal mutations on BRCA1 and BRCA2 genes are the most important biomarkers in epithelial ovarian cancer having prognostic and predictive value. This article will review the histological and molecular characteristics of the five subtypes of ovarian cancer, describing the most important biomarkers and mutations that can guide in diagnosis, screening and tailored treatment strategy.

Exploiting DNA repair defects for novel cancer therapies

Most human tumors accumulate a multitude of genetic changes due to defects in the DNA damage response. Recently, small-molecule inhibitors have been developed that target cells with specific DNA repair defects, providing hope for precision treatment of such tumors. Here we discuss the rationale behind these therapies and how an important bottleneck—patient selection—can be approached.

Defects in homologous recombination repair behind the human diseases: FA and HBOC

Hereditary breast and ovarian cancer (HBOC) syndrome and a rare childhood disorder Fanconi anemia (FA) are caused by homologous recombination (HR) defects, and some of the causative genes overlap. Recent studies in this field have led to the exciting development of PARP inhibitors as novel cancer therapeutics and have clarified important mechanisms underlying genome instability and tumor suppression in HR-defective disorders. In this review, we provide an overview of the basic molecular mechanisms governing HR and DNA crosslink repair, highlighting BRCA2, and the intriguing relationship between HBOC and FA.

Cytotoxic and targeted therapy for hereditary cancers

There is a number of drugs demonstrating specific activity towards hereditary cancers. For example, tumors in BRCA1/2 mutation carriers usually arise via somatic inactivation of the remaining BRCA allele, which makes them particularly sensitive to platinum-based drugs, PARP inhibitors (PARPi), mitomycin C, liposomal doxorubicin, etc. There are several molecular assays for BRCA-ness, which permit to reveal BRCA-like phenocopies among sporadic tumors and thus extend clinical indications for the use of BRCA-specific therapies. Retrospective data on high-dose chemotherapy deserve consideration given some unexpected instances of cure from metastatic disease among BRCA1/2-mutated patients. Hereditary non-polyposis colorectal cancer (HNPCC) is characterized by high-level microsatellite instability (MSI-H), increased antigenicity and elevated expression of immunosuppressive molecules. Recent clinical trial demonstrated tumor responses in HNPCC patients treated by the immune checkpoint inhibitor pembrolizumab. There are successful clinical trials on the use of novel targeted agents for the treatment or rare cancer syndromes, e.g. RET inhibitors for hereditary medullary thyroid cancer, mTOR inhibitors for tumors arising in patients with tuberous sclerosis (TSC), and SMO inhibitors for basal-cell nevus syndrome. Germ-line mutation tests will be increasingly used in the future for the choice of the optimal therapy, therefore turnaround time for these laboratory procedures needs to be significantly reduced to ensure proper treatment planning.

Levels of DNA Methylation Vary at CpG Sites across the BRCA1 Promoter, and Differ According to Triple Negative and "BRCA-Like" Status, in Both Blood and Tumour DNA

Triple negative breast cancer is typically an aggressive and difficult to treat subtype. It is often associated with loss of function of the BRCA1 gene, either through mutation, loss of heterozygosity or methylation. This study aimed to measure methylation of the BRCA1 gene promoter at individual CpG sites in blood, tumour and normal breast tissue, to assess whether levels were correlated between different tissues, and with triple negative receptor status, histopathological scoring for BRCA-like features and BRCA1 protein expression. Blood DNA methylation levels were significantly correlated with tumour methylation at 9 of 11 CpG sites examined (p<0.0007). The levels of tumour DNA methylation were significantly higher in triple negative tumours, and in tumours with high BRCA-like histopathological scores (10 of 11 CpG sites; p<0.01 and p<0.007 respectively). Similar results were observed in blood DNA (6 of 11 CpG sites; p<0.03 and 7 of 11 CpG sites; p<0.02 respectively). This study provides insight into the pattern of CpG methylation across the BRCA1 promoter, and supports previous studies suggesting that tumours with BRCA1 promoter methylation have similar features to those with BRCA1 mutations, and therefore may be suitable for the same targeted therapies.