Role of BRCA Mutations in the Modulation of Response to Platinum Therapy

Treatment outcome according to genetic tumour alterations and clinical characteristics in digestive high-grade neuroendocrine neoplasms

BACKGROUND

Chemotherapy has limited efficacy in advanced digestive high-grade neuroendocrine neoplasms (HG-NEN) and prognosis is dismal. Predictive markers for palliative chemotherapy are lacking, and prognostic markers are limited.

METHODS

Digestive HG-NEN patients (n = 229) were prospectively included 2013-2017. Pathological re-assessment revealed 188 neuroendocrine carcinomas (NEC) and 41 neuroendocrine tumours (NET G3). Tumour-DNA was sequenced across 360 cancer-related genes, assessing mutations (mut) and copy number alterations. We linked sequencing results to clinical information and explored potential markers for first-line chemotherapy efficacy and survival.

RESULTS

In NEC given cis/carboplatin and etoposide (PE), TP53mut predicted inferior response rate in multivariate analyses (p = 0.009) and no BRAFmut NEC showed response. In overall assessment of PE-treated NEC, no genetic alterations were prognostic for OS. For small-cell NEC, TP53mut were associated with longer OS (p = 0.011) and RB1 deletions predicted lack of immediate-progression (p = 0.003). In non-small cell NEC, APC mut were associated with immediate-progression and shorter PFS (p = 0.008/p = 0.004). For NET G3, ATRXmut, ARID1A- and ERS1 deletions were associated with shorter PFS.

CONCLUSION

Correlations between genetic alterations and response/immediate-progression to PE were frequent in NEC but affected PFS or OS only when subdividing for cell-type. The classification of digestive NEC into large- and small-cell seems therefore molecularly and clinically relevant.

Neoadjuvant talazoparib in patients with germline BRCA1/2 mutation-positive, early-stage triple-negative breast cancer: exploration of tumor BRCA mutational status

BACKGROUND

Talazoparib monotherapy in patients with germline BRCA-mutated, early-stage triple-negative breast cancer (TNBC) showed activity in the neoadjuvant setting in the phase II NEOTALA study (NCT03499353). These biomarker analyses further assessed the mutational landscape of the patients enrolled in the NEOTALA study.

METHODS

Baseline tumor tissue from the NEOTALA study was tested retrospectively using FoundationOne®CDx. To further hypothesis-driven correlative analyses, agnostic heat-map visualizations of the FoundationOne®CDx tumor dataset were used to assess overall mutational landscape and identify additional candidate predictive biomarkers of response.

RESULTS

All patients enrolled (N = 61) had TNBC. In the biomarker analysis population, 75.0% (39/52) and 25.0% (13/52) of patients exhibited BRCA1 and BRCA2 mutations, respectively. Strong concordance (97.8%) was observed between tumor BRCA and germline BRCA mutations, and 90.5% (38/42) of patients with tumor BRCA mutations evaluable for somatic-germline-zygosity were predicted to exhibit BRCA loss of heterozygosity (LOH). No patients had non-BRCA germline DNA damage response (DDR) gene variants with known/likely pathogenicity, based on a panel of 14 non-BRCA DDR genes. Ninety-eight percent of patients had TP53 mutations. Genomic LOH, assessed continuously or categorically, was not associated with response.

CONCLUSION

The results from this exploratory biomarker analysis support the central role of BRCA and TP53 mutations in tumor pathobiology. Furthermore, these data support assessing germline BRCA mutational status for molecular eligibility for talazoparib in patients with TNBC.

Incidental pathogenic germline alterations detected through liquid biopsy in patients with solid tumors: prevalence, clinical utility and implications

Liquid biopsy, a minimally invasive approach for detecting tumor biomarkers in blood, has emerged as a leading-edge technique in cancer precision medicine. New evidence has shown that liquid biopsies can incidentally detect pathogenic germline variants (PGVs) associated with cancer predisposition, including in patients with a cancer for which genetic testing is not recommended. The ability to detect these incidental PGV in cancer patients through liquid biopsy raises important questions regarding the management of this information and its clinical implications. This incidental identification of PGVs raises concerns about cancer predisposition and the potential impact on patient management, not only in terms of providing access to treatment based on the tumor molecular profiling, but also the management of revealing genetic predisposition in patients and families. Understanding how to interpret this information is essential to ensure proper decision-making and to optimize cancer treatment and prevention strategies. In this review we provide a comprehensive summary of current evidence of incidental PGVs in cancer predisposition genes identified by liquid biopsy in patients with cancer. We critically review the methodological considerations of liquid biopsy as a tool for germline diagnosis, clinical utility and potential implications for cancer prevention, treatment, and research.

CRISPR knockout genome-wide screens identify the HELQ-RAD52 axis in regulating the repair of cisplatin-induced single stranded DNA gaps

Treatment with genotoxic agents, such as platinum compounds, is still the mainstay therapeutical approach for the majority of cancers. Our understanding of the mechanisms of action of these drugs is however imperfect, and continuously evolving. Recent advances in the field highlighted single stranded DNA (ssDNA) gap accumulation as a potential determinant underlying cisplatin chemosensitivity, at least in some genetic backgrounds, such as BRCA mutations. Cisplatin-induced ssDNA gaps form upon the arrest of replication forks at sites of cisplatin adducts, and restart of DNA synthesis downstream of the lesion through repriming catalyzed by the PRIMPOL enzyme. Here, we show that PRIMPOL overexpression in otherwise wildtype cells results in accumulation of cisplatin-induced ssDNA gaps without sensitizing cells to cisplatin, suggesting that ssDNA gap accumulation does not confer cisplatin sensitivity in BRCA-proficient cells. To understand how ssDNA gaps may cause cellular sensitivity, we employed CRISPR-mediated genome-wide genetic screening to identify factors which enable the cytotoxicity of cisplatin-induced ssDNA gaps. We found that the helicase HELQ specifically suppresses cisplatin sensitivity in PRIMPOL-overexpressing cells, and this is associated with reduced ssDNA accumulation. We moreover identify RAD52 as a mediator of this pathway, and show that RAD52 promotes ssDNA gap accumulation through a BRCA-mediated mechanism. Our work identified the HELQ-RAD52-BRCA axis as a regulator of ssDNA gap processing, shedding light on the mechanisms of cisplatin sensitization in cancer therapy.

HR-positive/HER2-negative breast cancer arising in patients with or without BRCA2 mutation: different biological phenotype and similar prognosis

Background

BRCA2 plays a key role in homologous recombination. However, information regarding its mutations in Chinese patients with breast cancer remains limited.

Objectives

This study aimed to assess the clinicopathological characteristics of BRCA2 mutation breast cancer and explore the mutation's effect on hormone receptor (HR)-positive/human epidermal growth factor receptor 2 (HER2)-negative breast cancer survival in China.

Design

This hospital-based cohort study prospectively included 629 women with breast cancer diagnosed from 2008 to 2023 at Zhejiang Cancer Hospital in China.

Methods

We compared the clinicopathological characteristics and metastatic patterns and analysed the invasive disease-free survival (iDFS), distant relapse-free survival (DRFS) and first-line progression-free survival (PFS1) of patients with HR-positive/HER2-negative breast cancer according to BRCA2 mutations.

Results

Among the 629 patients, 78 had BRCA2 mutations (12.4%) and 551 did not (87.6%). The mean age at diagnosis was lower in the BRCA2 mutation breast cancer group than in the non-mutation breast cancer group (38.91 versus 41.94 years, p = 0.016). BRCA2 mutation breast cancers were more likely to be lymph node-positive than non-mutation breast cancers (73.0% versus 56.6%, p = 0.037). The pathological grade was higher in 47.1% of BRCA2 mutation breast cancers than in 29.6% of non-mutation breast cancers (p = 0.014). The proportions of patients with BRCA2 mutations who developed contralateral breast cancer (19.2% versus 8.8%, p = 0.004), breast cancer in the family (53.8% versus 38.3%, p = 0.009) and ovarian cancer in the family (7.6% versus 2.4%, p = 0.022) were higher than those of patients without the mutation. The median follow-up time was 92.78 months. Multivariate analysis showed that BRCA2 mutation was not associated with poorer iDFS [hazard ratio = 0.9, 95% confidence interval (CI) = 0.64-1.27, p = 0.56] and poorer distant relapse-free survival (DRFS) (hazard ratio = 1.09, 95% CI = 0.61-1.93, p = 0.76). There was no significant difference between the two groups with regard to metastatic patterns in the advanced disease setting. In the first-line metastatic breast cancer setting, PFS1 expression was broadly similar between the two groups irrespective of chemotherapy or endocrine therapy.

Conclusion

HR-positive/HER2-negative breast cancer with BRCA2 mutations differs from those without mutations in clinical behaviour and reflects more aggressive tumour behaviour. Our results indicate that BRCA2 mutations have no significant effect on the survival of Chinese women with HR-positive/HER2-negative breast cancer.

Insights into molecular mechanisms of chemotherapy resistance in cancer

Cancer heterogeneity poses a significant hurdle to the successful treatment of the disease, and is being influenced by genetic inheritance, cellular and tissue biology, disease development, and response to therapy. While chemotherapeutic drugs have demonstrated effectiveness, their efficacy is impeded by challenges such as presence of resilient cancer stem cells, absence of specific biomarkers, and development of drug resistance. Often chemotherapy leads to a myriad of epigenetic, transcriptional and post-transcriptional alterations in gene expression as well as changes in protein expression, thereby leading to massive metabolic reprogramming. This review seeks to provide a detailed account of various transcriptional regulations, proteomic changes, and metabolic reprogramming in various cancer models in response to three primary chemotherapeutic interventions, docetaxel, carboplatin, and doxorubicin. Discussing the molecular targets of some of these regulatory events and highlighting their contribution in sensitivity to chemotherapy will provide insights into drug resistance mechanisms and uncover novel perspectives in cancer treatment.

Predictive and prognostic biomarkers in breast tumours

In the age of precision medicine, extensive research has investigated tumour biomarkers to predict the behaviour of cancer and/or response to treatment in order to better understand the prognosis and treatment of disease. In breast cancer, significant progress has been made to categorise a common disease into subtypes defined by intrinsic tumour biology, measured by tumour biomarkers. This review encompasses the established biomarkers within breast cancer with the most up-to-date information regarding their understanding and clinical use as predictive and/or prognostic markers of breast cancer.

Identification of indole-based natural compounds as inhibitors of PARP-1 against triple-negative breast cancer: a computational study

Triple-negative breast cancer (TNBC) is the most aggressive kind of breast cancer known to mankind. It is a heterogeneous disease that is formed due to the missing estrogen, progesterone and human epidermal growth factor 2 receptors. Poly(ADP-ribose) polymerase-1 (PARP-1) protein helps in the development of TNBC by repairing the cancer cells, which proliferate and spread metastatically. To determine the potential PARP-1 inhibitors (PARPi), 0.2 million natural products from Universal Natural Product Database were screened using molecular docking and six hit compounds were selected based on their binding affinity towards PARP-1. The bio-availability and drug-like properties of these natural products were evaluated using ADMET analysis. Molecular dynamics simulations were conducted for these complexes for 200 ns to examine their structural stability and dynamic behaviour and further compared with the complex of talazoparib (TALA), an FDA-approved PARPi. Using MM/PBSA calculations, we conclude that the complexes HIT-3 and HIT-5 (-25.64 and -23.14 kcal/mol, respectively) show stronger binding energies with PARP-1 than TALA with PARP-1 (-10.74 kcal/mol). Strong interactions were observed between the compounds and hotspot residues, Asp770, Ala880, Tyr889, Tyr896, Ala898, Asp899 and Tyr907, of PARP-1 due to the existence of various types of non-covalent interactions between the compounds and PARP-1. This research offers critical information about PARPi, which could potentially be incorporated into the treatment of TNBC. Moreover, these findings were validated by comparing them with an FDA-approved PARPi.

The effect of human umbilical cord mesenchymal stem cells conditioned medium combined with tamoxifen drug on BRCA1 and BRCA2 expression in breast cancer mouse models

BACKGROUND

A growing number of studies has indicated that the expression of Breast Cancer Susceptibility Genes 1 (BRCA1) and BRCA2 contribute to the resistance to DNA-damaging chemotherapies. Tamoxifen induces tumor cell death by suppressing estrogen receptor (ER) signaling and inducing DNA damage, and BRCA1 upregulation causes Tamoxifen chemoresistance in breast cancer cells. Consequently, this research study aimed to investigate the possible therapeutic effect of Human Umbilical Cord Mesenchymal Stem Cells Conditioned Medium (UCMSCs-CM) on sensitizing breast cancer cells to Tamoxifen by regulating BRCA1 and BRCA2 expression in vivo.

METHODS

Forty female mice, 4-8 weeks old, with weight of 150 g, were used for this study. Mouse 4T1 breast tumor models were established and then treated with UCMSCs-CM and Tamoxifen alone or in combination. After 10 days, the tumor masses were collected and the expression levels of BRCA1 and BRCA2 were evaluated using qRT-PCR assay.

RESULTS

The results obtained from qRT-PCR assay illustrated that UCMSCs-CM, either alone or in combination with Tamoxifen, significantly downregulated the mRNA expression levels of BRCA1 in breast cancer mouse models. However, both UCMSCs-CM and Tamoxifen indicated no statistically significant impact on BRCA2 mRNA expression compared to controls.

CONCLUSION

Our findings evidenced that UCMSCs-CM could be considered as a potential therapeutic option to modulate Tamoxifen chemosensitivity by regulating BRCA1 in breast cancer.

Metastatic Pancreatic Cancer: Where Are We?

Pancreatic cancer is one of the most lethal neoplasms worldwide; it is aggressive in nature and has a poor prognosis. The overall survival rate for pancreatic cancer is low. Most patients present non-specific symptoms in the advanced stages, which generally leads to late diagnosis, at which point there is no option for curative surgery. The treatment of metastatic pancreatic cancer includes systemic therapy, in some cases radiotherapy, and more recently, molecular targeted therapies, which can positively impact cancer control and improve quality of life. This review provides an overview of the molecular landscape of pancreatic cancer based on the most recent literature, as well as current treatment options for patients with metastatic pancreatic cancer.

ER-positive and BRCA2-mutated breast cancer: a literature review

BRCA2-mutated carriers have a high lifetime risk of breast cancer (BC), an early age of onset, and an increased risk of other cancers (including ovarian, pancreatic, and prostate cancer). Almost 70-80% of BRCA2-mutated BC are estrogen receptor (ER)-positive, which is a particular type of ER-positive BC that differs from sporadic ER-positive BC. This article reviews the clinicopathological features, treatment, and prognosis of ER-positive and BRCA2-mutated BC to provide a reference for clinical decision-making.

Comparison of poly (ADP-ribose) polymerase inhibitors (PARPis) as maintenance therapy for newly-diagnosed and platinum-sensitive recurrent ovarian cancer with BRCA mutational status: a systematic review and network meta-analysis

BACKGROUND

Poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors (PARPi) treatment for ovarian cancer (OC) are ever-changing. This study aimed to compare the efficacy and overall safety of available PARPi as maintenance therapy for BRCA mutation status in patients with newly diagnosed and platinum-sensitive recurrent (PSR) OC patients.

RESEARCH DESIGN AND METHODS

Relevant RCTs were systematically retrieved from PubMed and Embase until 31 May 2022. Progression-free survival (PFS) and overall survival (OS) based on BRCA mutation status and adverse events (AEs) regardless of mutation were efficacy and safety endpoints.

RESULTS

In newly diagnosed BRCAm-OC patients, olaparib (HR: 0.33; 95% confidence interval [CI]: 0.25, 0.43) and other PARPis [niraparib (HR: 0.40; 95% CI: 0.29, 0.55), rucaparib (HR: 0.40; 95% CI: 0.21, 0.76) and veliparib (HR: 0.44; 95% CI: 0.28, 0.69)] had a statistically significant effect on PFS versus placebo. In BRCAm-PSROC patients, Olaparib exhibited significant benefit (HR: 0.69; 95% CI: 0.54, 0.88) for OS compared to other PARPis. In BRCAwt-PSR OC patients, Olaparib showed a favorable OS benefit than other PARPis (HR: 0.84; 95% CI: 0.57,1.22). Overall, safety profile of all PARPis was acceptable.

CONCLUSION

All PARPis showed significant benefit, with olaparib showing greater benefit in newly diagnosed and PSR OC women.

REGISTRATION

CRD42021288932.

The Prognosis of Cancer Depends on the Interplay of Autophagy, Apoptosis, and Anoikis within the Tumor Microenvironment

Within the tumor microenvironment, the fight between the immune system and cancer influences tumor transformation. Metastasis formation is an important stage in the progression of cancer. This process is aided by cellular detachment and resistance to anoikis, which are achieved by altering intercellular signaling. Autophagy, specifically pro-survival autophagy, aids cancer cells in developing treatment resistance. Numerous studies have shown that autophagy promotes tumor growth and resistance to anoikis. To regulate protective autophagy, cancer-related genes phosphorylate both pro- and anti-apoptotic proteins. Apoptosis, a type of controlled cell death, eliminates damaged or unwanted cells. Anoikis is a type of programmed cell death in which cells lose contact with the extracellular matrix. The dysregulation of these cellular pathways promotes tumor growth and spread. Apoptosis, anoikis, and autophagy interact meticulously and differently depending on the cellular circumstances. For instance, autophagy can protect cancer cells from apoptosis by removing cellular components that are damaged and might otherwise trigger apoptotic pathways. Similarly, anoikis dysregulation can trigger autophagy by causing cellular harm and metabolic stress. In order to prevent or treat metastatic disease, specifically, targeting these cellular mechanisms may present a promising prospect for cancer therapy. This review discourses the state of our understanding of the molecular and cellular mechanisms underlying tumor transformation and the establishment of metastatic tumors. To enhance the prognosis for cancer, we highlight and discuss potential therapeutic approaches that target these processes and genes involved in them.

Real-world data in patients with BRCA mutated breast cancer treated with poly (ADP-ribose) polymerase inhibitors

Breast cancer is the most common type of cancer globally. Hereditary breast cancer accounts for 10% of new cases and 4%-5% of cases are associated to pathogenic variants in BRCA1 or BRCA2 genes. In recent years, poly-adenosine-diphosphate-ribose polymerase inhibitors (PARPi) olaparib and talazoparib have been approved for patients with BRCA-associated, HER2 -negative breast cancer. These drugs have shown positive results in the early and advanced setting with a favourable toxicity profile based on the OlympiAD, OlympiA and EMBRACA phase 3 trials. However, patients included in these randomised trials are highly selected, making toxicity and efficacy in patients encountered in routine clinical care a concern. Since the approval of olaparib and talazoparib for advanced human epidermal growth factor receptor 2-negative (HER2-negative) breast cancer, several phase IIIb-IV trials, expanded access cohorts, and retrospective cohorts have provided information on the efficacy and tolerability of these treatments in patient subgroups underrepresented in the registration trials, such as older adults, patients with poor performance status, and heavily pretreated patients. The aim of this review is to present a critical review of the information regarding the use of PARPi in real-world breast cancer patients.

BRCA-mutated gastric adenocarcinomas are associated with chromosomal instability and responsiveness to platinum-based chemotherapy

BACKGROUND

Homologous recombination defect is an important biomarker of chemotherapy in certain tumor types, and the presence of pathogenic or likely pathogenic mutations involving BRCA1 or BRCA2 (p-BRCA) mutations is the most well-established marker for the homologous recombination defect. Gastric cancer, one of the most prevalent tumor types in Asia, also harbors p-BRCA mutations.

METHODS

To investigate the clinical significance of p-BRCA mutations, we analyzed 366 gastric cancer cases through next-generation sequencing. We determined the zygosity of p-BRCA mutations based on the calculated tumor purity through variant allelic fraction patterns and investigated whether the presence of p-BRCA mutations is associated with platinum-based chemotherapy and a certain molecular subtype.

RESULTS

Biallelic p-BRCA mutation was associated with better response to platinum-based chemotherapy than heterozygous p-BRCA mutation or wild type BRCA genes. The biallelic p-BRCA mutations was observed only in the chromosomal instability subtype, while all p-BRCA mutations were heterozygous in microsatellite instability subtype.

CONCLUSIONS

In conclusion, patients with gastric cancer harboring biallelic p-BRCA mutations were associated with a good initial response to platinum-based chemotherapy and those tumors were exclusively chromosomal instability subtype. Further investigation for potential association with homologous recombination defect is warranted.

Real-World Efficacy and Safety of PARP Inhibitors in Recurrent Ovarian Cancer Patients With Somatic BRCA and Other Homologous Recombination Gene Mutations

BACKGROUND

Real-world data regarding the use of poly (ADP-ribose) polymerase (PARP) inhibitors in recurrent ovarian cancer patients with non-BRCA homologous recombination (HR) mutations or somatic BRCA mutations are lacking.

OBJECTIVE

The purpose of our study is to evaluate the response rate, duration of treatment, time to progression (TTP), and toxicities of olaparib, niraparib, and rucaparib in somatic BRCAm and non-BRCA HR-mutated patients.

METHODS

This was a retrospective study using the electronic medical record to identify patients across our health system who were initiated on a PARP inhibitor for ovarian cancer between December 2014 and December 2019. Patients were screened for the presence of a somatic BRCA1/2 mutation or a mutation in non-BRCA HR genes. Data were collected via chart review.

RESULTS

For the efficacy analysis, 8 patients had somatic BRCA mutations and 12 patients had HR mutations. The overall response rate (ORR) was 50% for BRCA-mutated (BRCAm) patients and 9.1% for non-BRCA HR-mutated (non-BRCA HRm) patients. 72.7% of patients with non-BRCA HR mutations had stable disease. The duration of therapy ranged from 2 to 66 months. The median TTP was 9.5 months. Overall, 66.7% of patients in the entire cohort started on a reduced dose of PARP inhibitor. Dose reductions due to AEs were observed in 52.4% of patients, while AEs requiring treatment interruption occurred in 61.9%.

CONCLUSION AND RELEVANCE

We found that PARP inhibitors provided stable disease in a high proportion of recurrent ovarian cancer patients who had pathogenic HR mutations, with toxicities comparable to major trials. Patients with non-BRCA HR and somatic BRCA mutations could benefit from PARP inhibitors.

Melodic maestros: Unraveling the role of miRNAs in the diagnosis, progression, and drug resistance of malignant pleural mesothelioma

Malignant pleural mesothelioma (MPM) is a highly lethal form of pleural cancer characterized by a scarcity of effective therapeutic interventions, resulting in unfavorable prognoses for afflicted individuals. Besides, many patients experience substantial consequences from being diagnosed in advanced stages. The available diagnostic, prognostic, and therapeutic options for MPM are restricted in scope. MicroRNAs (miRNAs) are a subset of small, noncoding RNA molecules that exert significant regulatory influence over several cellular processes within cell biology. A wide range of miRNAs have atypical expression patterns in cancer, serving specific functions as either tumor suppressors or oncomiRs. This review aims to collate, epitomize, and analyze the latest scholarly investigations on miRNAs that are believed to be implicated in the dysregulation leading to MPM. miRNAs are also discussed concerning their potential clinical usefulness as diagnostic and prognostic biomarkers for MPM. The future holds promising prospects for enhancing diagnostic, prognostic, and therapeutic modalities for MPM, with miRNAs emerging as a potential trigger for such advancements.

Clinical Characteristics, Response to Platinum-Based Chemotherapy and Poly (Adenosine Phosphate-Ribose) Polymerase Inhibitors in Advanced Lung Cancer Patients Harboring BRCA Mutations

The oncogenic role and clinical relevance of BRCA mutations in NSCLC remain unclear. We aim to evaluate the characteristics and clinical outcomes of patients with NSCLC harboring BRCA mutations treated at Hadassah Medical Center (HMC). We retrospectively assessed all patients with advanced NSCLC who underwent next-generation sequencing (NGS) and were found to have pathogenic somatic BRCA mutations (p-BRCA). We compared clinical outcomes in NSCLC patients with wild-type BRCA (wt-BRCA) matched by age, stage, gender, smoking, PDL-1 and driver mutations. Between 2015 and 2022, we evaluated 598 patients with advanced NSCLC using NGS and found 26 patients with p-BRCA, of whom 17 (65.4%) were carriers of germline BRCA variants and represented 1% of all BRCA carriers HMC. The median age of diagnosis was 67 years old (40-78), 13 patients (50%) had a history of smoking and 9 patients (34.6%) had additional driver mutations (EGFR, ALK, BRAF, MET or ERBB2). Objective response rate and median progression-free survival (PFS) for first-line platinum-based chemotherapy in the p-BRCA group compared to wt-BRCA controls were 72.2% and 16 months (CI 95%, 5-22), compared to 47.4% and 7 months (CI 95%, 5-9), respectively, and HR for PFS was 0.41 (CI 95%, 0.17-0.97). Six patients in the p-BRCA group were treated with advanced-line poly (adenosine-phosphate-ribose) polymerase inhibitors (PARPi), with a durable response observed in four patients (66%). In this cohort, patients with NSCLC harboring p-BRCA exhibit high-sensitivity PARPi and a prolonged response to platinum, suggesting some oncogenic role for BRCA mutations in NSCLC. The results support further prospective trials of the treatment of NSCLC harboring p-BRCA with PARPi.

Differential Sensitivity of Germline and Somatic BRCA Variants to PARP Inhibitor in High-Grade Serous Ovarian Cancer

PURPOSE

The introduction of PARP inhibitors (PARPis) as a treatment option for patients with high-grade serous ovarian cancer (HGSOC) modified the approach of BRCA testing worldwide. In this study, we aim to evaluate the impact of BRCA1 and BRCA2 variants on treatment response and survival outcomes in patients diagnosed in our institution.

METHODS

A total of 805 HGSOC samples underwent BRCA1 and BRCA2 variant detection by using next-generation sequencing (NGS). Among them, a pathogenic alteration was detected in 104 specimens. Clinicopathological features and germline status were recovered, and alteration types were further characterized. The clinical significance of variant type in terms of response to chemotherapy and to PARPis as well as overall survival were evaluated using univariate analysis.

RESULTS

In our cohort, 13.2% of the HGSOC samples harbored a pathogenic BRCA1 or BRCA2 variant, among which 58.7% were inherited. No difference was observed between germline and somatic variants in terms of the gene altered. Interestingly, patients with somatic variants only (no germline) demonstrated better outcomes under PARPi treatment compared to those with germline ones.

CONCLUSION

The determination of the inheritance or acquisition of BRCA1 and BRCA2 alterations could provide valuable information for improving management strategies and predicting the outcome of patients with HGSOC.

A phase III, multicenter, randomized study of olvimulogene nanivacirepvec followed by platinum-doublet chemotherapy and bevacizumab compared with platinum-doublet chemotherapy and bevacizumab in women with platinum-resistant/refractory ovarian cancer

BACKGROUND

Treatment options for patients with platinum-resistant/refractory ovarian cancers are limited and only marginally effective. The development of novel, more effective therapies addresses a critical unmet medical need. Olvimulogene nanivacirepvec (Olvi-Vec), with its strong immune modulating effect on the tumor microenvironment, may provide re-sensitization to platinum and clinically reverse platinum resistance or refractoriness in platinum-resistant/refractory ovarian cancer.

PRIMARY OBJECTIVE

The primary objective is to evaluate the efficacy of intra-peritoneal Olvi-Vec followed by platinum-based chemotherapy and bevacizumab in patients with platinum-resistant/refractory ovarian cancer.

STUDY HYPOTHESIS

This phase III study investigates Olvi-Vec oncolytic immunotherapy followed by platinum-based chemotherapy and bevacizumab as an immunochemotherapy evaluating the hypothesis that such sequential combination therapy will prolong progression-free survival (PFS) and bring other clinical benefits compared with treatment with platinum-based chemotherapy and bevacizumab.

TRIAL DESIGN

This is a multicenter, prospective, randomized, and active-controlled phase III trial. Patients will be randomized 2:1 into the experimental arm treated with Olvi-Vec followed by platinum-doublet chemotherapy and bevacizumab or the control arm treated with platinum-doublet chemotherapy and bevacizumab.

MAJOR INCLUSION/EXCLUSION CRITERIA

Eligible patients must have recurrent, platinum-resistant/refractory, non-resectable high-grade serous, endometrioid, or clear-cell ovarian, fallopian tube, or primary peritoneal cancer. Patients must have had ≥3 lines of prior chemotherapy.

PRIMARY ENDPOINT

The primary endpoint is PFS in the intention-to-treat population.

SAMPLE SIZE

Approximately 186 patients (approximately 124 patients randomized to the experimental arm and 62 to the control arm) will be enrolled to capture 127 PFS events.

ESTIMATED DATES FOR COMPLETING ACCRUAL AND PRESENTING RESULTS

Expected complete accrual in 2024 with presentation of primary endpoint results in 2025.

TRIAL REGISTRATION

NCT05281471.

Exceptional Response to Olaparib: A Case Report of Metastatic Esophageal Squamous Cell Carcinoma in a Patient With Fanconi Anemia, Germline FANCA Mutation, and Somatic BRCA2 Mutations

Exceptional response to olaparib in a case with Fanconi anemia and metastatic esophageal carcinoma

Platinum Sensitivity in IDH1/2 Mutated Intrahepatic Cholangiocarcinoma: Not All "BRCAness" Is Created Equal

Preclinical data suggest that IDH1/2 mutations result in defective homologous recombination repair (HRR). We hypothesized that patients with IDH1/2mt intrahepatic cholangiocarcinoma (IHCC) would benefit more from 1 L platinum chemotherapy than patients with wildtype (WT) tumors. We performed a multicenter retrospective study of 81 patients with unresectable IHCC treated with 1 L platinum with a primary endpoint of clinical benefit rate (CBR). Patients with IDH1/2mt tumors had a similar CBR and objective response rate compared to those with IDH WT disease (59 versus 54%; p = 0.803), suggesting that a relationship between platinum sensitivity and HRR gene defects may be specific to tumor context.

Clinical Activity of Olvimulogene Nanivacirepvec-Primed Immunochemotherapy in Heavily Pretreated Patients With Platinum-Resistant or Platinum-Refractory Ovarian Cancer: The Nonrandomized Phase 2 VIRO-15 Clinical Trial

Importance

Patients with platinum-resistant or platinum-refractory ovarian cancer (PRROC) have limited therapeutic options, representing a considerable unmet medical need.

Objective

To assess antitumor activity and safety of intraperitoneal (IP) olvimulogene nanivacirepvec (Olvi-Vec) virotherapy and platinum-based chemotherapy with or without bevacizumab in patients with PRROC.

Design, Setting, and Participants

This open-label, nonrandomized multisite phase 2 VIRO-15 clinical trial enrolled patients with PRROC with disease progression following their last prior line of therapy from September 2016 to September 2019. Data cutoff was on March 31, 2022, and data were analyzed between April 2022 and September 2022.

Interventions

Olvi-Vec was administered via a temporary IP dialysis catheter as 2 consecutive daily doses (3 × 109 pfu/d) followed by platinum-doublet chemotherapy with or without bevacizumab.

Main Outcomes and Measures

Primary outcomes were objective response rate (ORR) via Response Evaluation Criteria in Solid Tumors, version 1.1 (RECIST 1.1) and cancer antigen 125 (CA-125) assay, and progression-free survival (PFS). Secondary outcomes included duration of response (DOR), disease control rate (DCR), safety, and overall survival (OS).

Results

Twenty-seven heavily pretreated patients with platinum-resistant (n = 14) or platinum-refractory (n = 13) ovarian cancer were enrolled. The median (range) age was 62 (35-78) years. The median (range) prior lines of therapy were 4 (2-9). All patients completed both Olvi-Vec infusions and chemotherapy. Median follow-up duration was 47.0 months (95% CI, 35.9 months to NA). Overall, ORR by RECIST 1.1 was 54% (95% CI, 33%-74%), with a DOR of 7.6 months (95% CI, 3.7-9.6 months). The DCR was 88% (21/24). The ORR by CA-125 was 85% (95% CI, 65%-96%). Median PFS by RECIST 1.1 was 11.0 months (95% CI, 6.7-13.0 months), and the PFS 6-month rate was 77%. Median PFS was 10.0 months (95% CI, 6.4-NA months) in the platinum-resistant group and 11.4 months (95% CI, 4.3-13.2 months) in the platinum-refractory group. The median OS was 15.7 months (95% CI, 12.3-23.8 months) in all patients, with a median OS of 18.5 months (95% CI, 11.3-23.8 months) in the platinum-resistant group and 14.7 months (95% CI, 10.8-33.6 months) in the platinum-refractory group. Most frequent treatment-related adverse events (TRAEs) (any grade, grade 3) were pyrexia (63.0%, 3.7%, respectively) and abdominal pain (51.9%, 7.4%, respectively). There were no grade 4 TRAEs, and no treatment-related discontinuations or deaths.

Conclusions and Relevance

In this phase 2 nonrandomized clinical trial, Olvi-Vec followed by platinum-based chemotherapy with or without bevacizumab as immunochemotherapy demonstrated promising ORR and PFS with a manageable safety profile in patients with PRROC. These hypothesis-generating results warrant further evaluation in a confirmatory phase 3 trial.

Trial Registration

ClinicalTrials.gov Identifier: NCT02759588.

Proteomic analysis reveals CAAP1 negatively correlates with platinum resistance in ovarian cancer

The present study sought to investigate the correlation between CAAP1 and platinum resistance in ovarian cancer and to preliminarily explore the potential biological function of CAAP1. Proteomic analysis was used to analyze differentially expressed proteins in platinum-sensitive and -resistant tissue samples of ovarian cancer. The Kaplan-Meier plotter was used for prognostic analysis. Immunohistochemistry assay and chi-square test were employed to explore the relationship between CAAP1 and platinum resistance in tissue samples. Lentivirus transfection, immunoprecipitation-mass spectrometry, and bioinformatics analysis were used to determine the potential biological function of CAAP1. Based on results, the expression level of CAAP1 was significantly higher in platinum-sensitive tissues compared to that in resistant tissues. Chi-square test demonstrated that there is a negative correlation between high expression of CAAP1 and platinum resistance. Overexpression of CAAP1 increased cis‑platinum sensitivity of the A2780/DDP cell line likely via the mRNA splicing pathway by interacting with the splicing factor AKAP17A. In summary, there is a negative correlation between high expression of CAAP1 and platinum resistance. CAAP1 might be a potential biomarker for platinum resistance in ovarian cancer. SIGNIFICANCE: Platinum resistance is a key factor affecting the survival of ovarian cancer patients. Understanding the mechanisms of platinum resistance is highly important for ovarian cancer management. Here, we performed the DIA- and DDA-based proteomics to analyze differentially expressed proteins in tissue and cell samples of ovarian cancer. We found that the protein identified as CAAP1, which was first reported to be involved in the regulation of apoptosis, may be negatively correlates with platinum resistance in ovarian cancer. In addition, we also found that CAAP1 enhanced the sensitivity of platinum-resistant cells to cis‑platinum via the mRNA splicing pathway by interacting with the splicing factor AKAP17A. Our data would be useful to reveal novel molecular mechanisms of platinum resistance in ovarian cancer.

Glucocorticoid Receptor and Ovarian Cancer: From Biology to Therapeutic Intervention

Ovarian cancer (OC) is the leading cause of death from gynecological malignancies worldwide. Fortunately, recent advances in OC biology and the discovery of novel therapeutic targets have led to the development of novel therapeutic agents that may improve the outcome of OC patients. The glucocorticoid receptor (GR) is a ligand-dependent transcriptional factor known for its role in body stress reactions, energy homeostasis and immune regulation. Notably, evidence suggests that GR may play a relevant role in tumor progression and may affect treatment response. In cell culture models, administration of low levels of glucocorticoids (GCs) suppresses OC growth and metastasis. Conversely, high GR expression has been associated with poor prognostic features and long-term outcomes in patients with OC. Moreover, both preclinical and clinical data have shown that GR activation impairs the effectiveness of chemotherapy by inducing the apoptotic pathways and cell differentiation. In this narrative review, we summarize data related to the function and role of GR in OC. To this aim, we reorganized the controversial and fragmented data regarding GR activity in OC and herein describe its potential use as a prognostic and predictive biomarker. Moreover, we explored the interplay between GR and BRCA expression and reviewed the latest therapeutic strategies such as non-selective GR antagonists and selective GR modulators to enhance chemotherapy sensitivity, and to finally provide new treatment options in OC patients.

Retarding breast tumor growth with nanoparticle-facilitated intravenous delivery of BRCA1 and BRCA2 tumor suppressor genes

Gene augmentation therapy entails replacement of the abnormal tumor suppressor genes in cancer cells. In this study, we performed gene augmentation for BRCA1/2 tumor suppressors in order to retard tumor development in breast cancer mouse model. We formulated inorganic carbonate apatite (CA) nanoparticles (NPs) to carry and deliver the purified BRCA1/2 gene- bearing plasmid DNA both in vitro and in vivo. The outcome of BRCA1/2 plasmid-loaded NPs delivery on cellular viability of three breast cancer cell lines such as MCF-7, MDA-MB-231 and 4T1 were evaluated by MTT assay. The result in MCF-7 cell line exhibited that transfection of BRCA 1/2 plasmids with CA NPs significantly reduced cancer cell growth in comparison to control group. Moreover, we noticed a likely pattern of cellular cytotoxicity in 4T1 murine cancer cell line. Following transfection with BRCA1 plasmid-loaded NPs, and Western blot analysis, a notable reduction in the phospho-MAPK protein of MAPK signaling pathway was detected, revealing reduced growth signal. Furthermore, in vivo study in 4T1 induced breast cancer mouse model showed that the tumor growth rate and final volume were decreased significantly in the mouse group treated intravenously with BRCA1 + NPs and BRCA2 + NPs formulations. Our results established that BRCA1/2 plasmids incorporated into CA NPs mitigated breast tumor growth, signifying their application in the therapy for breast cancer.

Compounds from diverse natural origin against triple-negative breast cancer: A comprehensive review

Triple-negative breast cancer (TNBC) is caused due to the lack of estrogen receptors (ER), progesterone receptors (PR), and human epidermal growth factor 2 (HER2) expression. Triple-negative breast cancer is the most aggressive heterogeneous disease that is capable of producing different clones and mutations. Tumorigenesis in TNBC is caused due to the mutation or overexpression of tumor suppressor genes. It is also associated with mutations in the BRCA gene which is linked to hereditary breast cancer. In addition, PARP proteins and checkpoint proteins also play a crucial function in causing TNBC. Many cell signaling pathways are dysregulated in TNBC. Even though chemotherapy and immunotherapy are good options for TNBC treatment, the response rates are still low in general. Many phytochemicals that are derived from natural compounds have shown very good inhibitions for TNBC. Natural compounds have the great advantage of being less toxic, having lesser side effects, and being easily available. The secondary metabolites such as alkaloids, terpenoids, steroids, and flavonoids in natural products make them promising inhibitors of TNBC. Their compositions also offer vital insights into inhibitory action, which could lead to new cancer-fighting strategies. This review can help in understanding how naturally occurring substances and medicinal herbs decrease specific tumors and pave the way for the development of novel and extremely efficient antitumor therapies.

The therapeutic relevance of a BRCA2 mutation in a patient with recurrent thymoma: a case report

Background

Thymomas are characterized by a low tumor mutation burden and a paucity of actionable mutations. Clinical behavior can vary from relatively indolent to very aggressive and impact survival. Platinum-based chemotherapy is the primary treatment modality for inoperable disease and is palliative in intent. Patients with advanced thymoma frequently experience disease recurrence after frontline therapy. Treatment options for relapsed thymoma are relatively limited. A case of recurrent thymoma harboring a breast cancer gene 2 (BRCA2) mutation was presented for multidisciplinary discussion at the International Thymic Malignancy Interest Group (ITMIG) Tumor Board meeting.

Case Description

A 63-year-old female presented with Tumor Node Metastasis (TNM) stage I, World Health Organization (WHO) subtype B1 thymoma at diagnosis and underwent surgical resection. First recurrence occurred in the left costophrenic recess and was treated with preoperative external beam radiotherapy (EBRT), surgical excision, and post-operative chemotherapy. Histology was consistent with WHO subtype B2 thymoma and genomic analysis of the resected tumor detected a BRCA2 mutation. Second recurrence occurred in the mediastinum and bilateral pleurae. Mediastinal disease was treated with EBRT, and the pleural deposits were observed initially. However, upon further progression, the case was discussed at the ITMIG tumor board meeting to determine optimal second line therapy for this patient.

Conclusions

A potential role of poly (ADP-ribose) polymerase (PARP) inhibitors versus cytotoxic chemotherapy for treatment of BRCA2-mutated recurrent thymoma merits discussion. However, due to the absence of data to support the functional and therapeutic significance of BRCA2 mutations in patients with thymoma, the potential for severe toxicity associated with PARP inhibitors, and availability of other safe and effective alternatives, other treatment options should be considered. PARP inhibitors can be considered for treatment of BRCA2-mutated thymomas as part of a clinical trial or when other treatment options have been exhausted.

Pharmacotherapeutic options for pancreatic ductal adenocarcinoma

INTRODUCTION

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy projected to be the 2^nd leading cause of cancer related death in the USA by 2030. This manuscript discusses current and evolving treatment approaches in patients with pancreatic cancer.

AREAS COVERED

PDAC is classified as: a) resectable, b) borderline resectable, c) unresectable (locally advanced and metastatic). The standard of care for patients who present with resectable pancreatic adenocarcinoma is six months of adjuvant modified (m) FOLFIRINOX, gemcitabine plus capecitabine, or single agent gemcitabine. For many reasons, there has been a paradigm shift to employing neoadjuvant chemotherapy. For resectable and borderline resectable patients, we generally start with systemic therapy and reevaluate resectability with subsequent scans specifically when the tumor is located in the head or body of the pancreas. Combined chemoradiation therapy can be employed in select patients. The standard of care for metastatic PDAC is FOLFIRINOX or gemcitabine and nab-paclitaxel. Germline and somatic genomic profiling should be obtained in all patients. Patients with a germline BRCA mutation can receive upfront gemcitabine and cisplatin.

EXPERT OPINION

Thorough understanding of molecular pathogenesis in PDAC has opened various therapeutic avenues. We remain optimistic that future treatment modalities such as targeted therapies, cellular therapies and immunotherapy will further improve survival in PDAC.

Error-prone repair of stalled replication forks drives mutagenesis and loss of heterozygosity in haploinsufficient BRCA1 cells

Germline mutations in the BRCA genes are associated with a higher risk of carcinogenesis, which is linked to an increased mutation rate and loss of the second unaffected BRCA allele (loss of heterozygosity, LOH). However, the mechanisms triggering mutagenesis are not clearly understood. The BRCA genes contain high numbers of repetitive DNA sequences. We detected replication forks stalling, DNA breaks, and deletions at these sites in haploinsufficient BRCA cells, thus identifying the BRCA genes as fragile sites. Next, we found that stalled forks are repaired by error-prone pathways, such as microhomology-mediated break-induced replication (MMBIR) in haploinsufficient BRCA1 breast epithelial cells. We detected MMBIR mutations in BRCA1 tumor cells and noticed deletions-insertions (>50 bp) at the BRCA1 genes in BRCA1 patients. Altogether, these results suggest that under stress, error-prone repair of stalled forks is upregulated and induces mutations, including complex genomic rearrangements at the BRCA genes (LOH), in haploinsufficient BRCA1 cells.

Critical DNA damaging pathways in tumorigenesis

The acquisition of DNA damage is an early driving event in tumorigenesis. Premalignant lesions show activated DNA damage responses and inactivation of DNA damage checkpoints promotes malignant transformation. However, DNA damage is also a targetable vulnerability in cancer cells. This requires a detailed understanding of the cellular and molecular mechanisms governing DNA integrity. Here, we review current work on DNA damage in tumorigenesis. We discuss DNA double strand break repair, how repair pathways contribute to tumorigenesis, and how double strand breaks are linked to the tumor microenvironment. Next, we discuss the role of oncogenes in promoting DNA damage through replication stress. Finally, we discuss our current understanding on DNA damage in micronuclei and discuss therapies targeting these DNA damage pathways.

Unboxing the molecular modalities of mutagens in cancer

The etiology of the majority of human cancers is associated with a myriad of environmental causes, including physical, chemical, and biological factors. DNA damage induced by such mutagens is the initial step in the process of carcinogenesis resulting in the accumulation of mutations. Mutational events are considered the major triggers for introducing genetic and epigenetic insults such as DNA crosslinks, single- and double-strand DNA breaks, formation of DNA adducts, mismatched bases, modification in histones, DNA methylation, and microRNA alterations. However, DNA repair mechanisms are devoted to protect the DNA to ensure genetic stability, any aberrations in these calibrated mechanisms provoke cancer occurrence. Comprehensive knowledge of the type of mutagens and carcinogens and the influence of these agents in DNA damage and cancer induction is crucial to develop rational anticancer strategies. This review delineated the molecular mechanism of DNA damage and the repair pathways to provide a deep understanding of the molecular basis of mutagenicity and carcinogenicity. A relationship between DNA adduct formation and cancer incidence has also been summarized. The mechanistic basis of inflammatory response and oxidative damage triggered by mutagens in tumorigenesis has also been highlighted. We elucidated the interesting interplay between DNA damage response and immune system mechanisms. We addressed the current understanding of DNA repair targeted therapies and DNA damaging chemotherapeutic agents for cancer treatment and discussed how antiviral agents, anti-inflammatory drugs, and immunotherapeutic agents combined with traditional approaches lay the foundations for future cancer therapies.

Real-World Data on Newly Diagnosed BRCA-Mutated High-Grade Epithelial Ovarian Cancers: The French National Multicenter ESME Database

Simple Summary

BRCA-mutated high-grade epithelial ovarian cancers represent a specific subset of gynecological malignancies. Real-world comprehensive data have been elusive to date. As such, we conducted a comprehensive description of clinicopathological and therapeutical characteristics via the Epidemiological Strategy and Medical Economics (ESME) data warehouse, which collects data from 18 French comprehensive cancer centers from the Unicancer network. This led to useful findings regarding the natural disease history of these patients in clinical practice, prior to the advent of poly-ADP ribose polymerase inhibitors.

Abstract

Background: In spite of the frequency and clinical impact of BRCA1/2 alterations in high-grade epithelial ovarian cancer (HGEOC), real-world information based on robust data warehouse has been scarce to date. Methods: Consecutive patients with BRCA-mutated HGEOC treated between 2011 and 2016 within French comprehensive cancer centers from the Unicancer network were extracted from the ESME database. The main objective of the study was the assessment of clinicopathological and treatments parameters. Results: Out of the 8021 patients included in the ESME database, 266 patients matching the selection criteria were included. BRCA1 mutation was found in 191 (71.8%) patients, while 75 (28.2%) had a BRCA2 mutation only; 95.5% of patients received a cytoreductive surgery. All patients received a taxane/platinum-based chemotherapy (median = six cycles). Complete and partial response were obtained in 53.3% and 20.4% of the cases, respectively. Maintenance therapy was administered in 55.3% of the cases, bevacizumab being the most common agent. After a median follow up of 51.7 months, a median progression-free survival of 28.6 months (95% confidence interval (CI) [26.5; 32.7]) and an estimated 5-year median overall survival of 69.2% (95% CI [61.6; 70.3]) were reported. Notably, BRCA1- and BRCA2-mutated cases exhibited a trend towards different median progression-free survivals, with 28.0 (95% CI [24.4; 32.3]) and 33.3 months (95% CI [26.7; 46.1]), respectively (p-value = 0.053). Furthermore, five-year OS for BRCA1-mutated patients was 64.5% (95% CI [59.7; 69.2]), while it was 82.5% (95% CI [76.6; 88.5]) for BRCA2-mutated ones (p-value = 0.029). Conclusions: This study reports the largest French multicenter cohort of BRCA-mutated HGEOCs based on robust data from the ESME, exhibiting relevant real-world data regarding this specific population.

Efficacy and safety of talazoparib in Japanese patients with germline BRCA-mutated locally advanced or metastatic breast cancer: results of the phase 1 dose-expansion study

Background

Talazoparib, a poly(ADP-ribose) polymerase enzyme inhibitor, is approved for the treatment of patients with germline BRCA1/2 (gBRCA1/2)-mutated HER2-negative advanced breast cancer. This two-part study, a recently published dose-escalation part followed by the dose-expansion part reported here, evaluated the efficacy and safety of talazoparib in Japanese patients with gBRCA1/2-mutated advanced breast cancer.

Methods

In this open-label, multicenter phase 1 study (NCT03343054), the primary endpoint of the dose-expansion part was confirmed objective response rate (ORR), determined by investigator assessment (RECIST 1.1). Secondary endpoints included progression-free survival (PFS), overall survival (OS), safety, and pharmacokinetics. Patients received the recommended phase 2 dose (1 mg/day; 0.75 mg/day moderate renal impairment).

Results

Nineteen Japanese patients with gBRCA1/2-mutated locally advanced or metastatic breast cancer were enrolled. Confirmed ORR was 57.9% (11/19; 90% confidence interval [CI] 36.8–77.0). Stable disease was observed in 36.8% (7/19) of patients. Per investigator assessment, median PFS was 7.2 months (95% CI 4.1–not estimable) and 12-month OS rate was 84.7% (90% CI 57.5–95.1). Median OS was not reached; 17/19 patients were alive and censored at 12 months. All patients experienced treatment-related adverse events (AEs); the majority were hematologic. The most common treatment-related AE was anemia (68.4%; [13/19]). Grade 3/4 treatment-related AEs were observed in 52.6% (10/19) of patients. During the safety period, there were no grade 5 treatment-emergent AEs, treatment-related serious AEs, or deaths.

Conclusions

In Japanese patients with gBRCA mutations and locally advanced or metastatic breast cancer, talazoparib monotherapy was generally well tolerated and resulted in clinically meaningful ORRs.

Clinicaltrials.gov identifier

NCT03343054.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12282-022-01390-w.

Platinum-based adjuvant therapy was efficient for triple-negative breast cancer: a meta-analysis from randomized controlled trials

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer. Neoadjuvant chemotherapy was widely accepted for treating TNBC. This systematic review and meta-analysis aimed to evaluate the efficacy, safety, and survival benefit of platinum-based adjuvant therapy (PBAT) in treating TNBC. The keywords were searched in Medline, Embase, Pubmed, and Cochrane Library database up to July 24, 2022. All the randomized control trials (RCTs) comparing PBAT and non-PBAT in treating TNBC were included in our study. The pathological complete remission (pCR) and complications were compared by odds ratio (OR) and 95% confidence intervals (CIs). The overall survival (OS) and relapse-free survival (RFS) were compared by hazard ratio (HR) and 95% CIs. A total of 19 RCTs were included in our meta-analysis, among which 2,501 patients were treated with PBAT and 2,290 with non-PBAT. The patients treated with PBAT combined a significantly higher pCR rate compared to those patients treated with non-PBAT (49.8% versus 36.4%, OR = 1.27, 95%CI = 1.14-1.43, P < 0.001). Besides, patients treated with PBAT had a significantly better RFS (HR = 0.78, 95%CI = 0.63-0.95, P = 0.016), but not in OS (HR = 0.84, P = 0.304). Although the occurrence of neutropenia and nausea were slightly different between the PBAT group (51.5% and 24.4%) and the non-PBAT group (47.0% and 29.4%), the complications were acceptable in the two treatments groups. Our results demonstrated that TNBC patients treated with PBAT could achieve a higher pCR rate and better RFS benefit without a higher complication rate.Highlights Platinum-based adjuvant therapy provided a higher pCR rate for TNBC.Platinum-based adjuvant therapy prolonged the RFS but without prolongingthe OS.Neutropenia and nausea rate was different between group PBAT and non-PBAT.

ST08 Altered NF-κB Pathway in Breast Cancer Cells In Vitro as Revealed by miRNA-mRNA Analysis and Enhanced the Effect of Cisplatin on Tumour Reduction in EAC Mouse Model

ST08 is a novel curcumin derivative that exhibited apoptotic and anti-migratory activity in MDA-MB-231, triple-negative breast cancer cells reported earlier. In this study, we further explored the anticancer properties of ST08. ST08 reduced tumor burden in vivo and induced apoptosis through the mitochondrial pathway both in vitro and in vivo. ST08 potentiated the effect of cisplatin in vitro and in vivo in mouse EAC breast cancer models with minimal toxicity. ST08 induced alterations in the gene expression were studied by parallel analysis of miRNA and mRNA. 74 differentially expressed miRNA regulated 114 mRNA in triple-negative (MDA-MB-231) cancer cells. Pathway related to the ECM was altered in mesenchymal MDA-MB-231 cells. We constructed a unique miRNA-mRNA interaction network, and one of the pathways regulated by miRNA was NF-κB. Targets of NF-κB like MMP1, PTX3, and MMP2 were downregulated in MDA-MB-231 in response to ST08 treatment. PMA induced cell proliferation was abrogated by ST08 treatment, and no additional cell cytotoxicity was observed when used in combination with IKK-16 indicating ST08 regulation of NF-κB pathway in MDA-MB-231 cells.

BAP1 loss by immunohistochemistry predicts improved survival to first line platinum/pemetrexed chemotherapy for pleural mesothelioma patients: A validation study

INTRODUCTION

Pleural mesothelioma (PM) is an aggressive malignancy with no identified predictive biomarkers. We assessed whether tumour BRCA associated protein 1 (BAP1) status is a predictive biomarker for survival in patients receiving first-line combination platinum/pemetrexed therapy.introduction METHODS: PM cases (n=114) from Aalborg, Denmark were stained for BAP1 on tissue microarrays. Demographic, clinical and survival data were extracted from registries and medical records. Surgical cases were excluded. BAP1 status was associated with overall survival (OS) by Cox regression and Kaplan-Meier methods. Results were validated in an independent cohort from Perth, Australia (n=234).

RESULTS

BAP1 loss was demonstrated in 62% and 60.3% of all Danish and Australian samples respectively. BAP1 loss was an independent predictor of OS in multivariate analyses corrected for histology, performance status, age, sex and treatment (HR = 2.49, p < 0.001 and 1.48, p = 0.01, respectively). First-line platinum/pemetrexed treated patients with BAP1 loss had significantly longer median survival than those with retained BAP1 in both the Danish (20.1 vs 7.3 months, p < 0.001) and Australian cohorts (19.6 vs 11.1 months, p < 0.01). Survival in patients with BAP1 retained and treated with platinum/pemetrexed was similar as in those with best supportive care (BSC). There was a higher OS in BSC patients with BAP1 loss, but significant only in the Australian cohort (16.8 vs 8.3 months, p < 0.01).results CONCLUSION: BAP1 is a predictive biomarker for survival following first-line combination platinum/pemetrexed chemotherapy and a potential prognostic marker in PM. BAP1 in tumour is a promising clinical tool for treatment stratification.

CONCLUSION

Novel Ex Vivo Models of Epithelial Ovarian Cancer: The Future of Biomarker and Therapeutic Research

Epithelial ovarian cancer (EOC) is a heterogenous disease associated with variations in presentation, pathology and prognosis. Advanced EOC is typified by frequent relapse and a historical 5-year survival of less than 30% despite improvements in surgical and systemic treatment. The advent of next generation sequencing has led to notable advances in the field of personalised medicine for many cancer types. Success in achieving cure in advanced EOC has however been limited, although significant prolongation of survival has been demonstrated. Development of novel research platforms is therefore necessary to address the rapidly advancing field of early diagnostics and therapeutics, whilst also acknowledging the significant tumour heterogeneity associated with EOC. Within available tumour models, patient-derived organoids (PDO) and explant tumour slices have demonstrated particular promise as novel ex vivo systems to model different cancer types including ovarian cancer. PDOs are organ specific 3D tumour cultures that can accurately represent the histology and genomics of their native tumour, as well as offer the possibility as models for pharmaceutical drug testing platforms, offering timing advantages and potential use as prospective personalised models to guide clinical decision-making. Such applications could maximise the benefit of drug treatments to patients on an individual level whilst minimising use of less effective, yet toxic, therapies. PDOs are likely to play a greater role in both academic research and drug development in the future and have the potential to revolutionise future patient treatment and clinical trial pathways. Similarly, ex vivo tumour slices or explants have also shown recent renewed promise in their ability to provide a fast, specific, platform for drug testing that accurately represents in vivo tumour response. Tumour explants retain tissue architecture, and thus incorporate the majority of tumour microenvironment making them an attractive method to re-capitulate in vivo conditions, again with significant timing and personalisation of treatment advantages for patients. This review will discuss the current treatment landscape and research models for EOC, their development and new advances towards the discovery of novel biomarkers or combinational therapeutic strategies to increase treatment options for women with ovarian cancer.

Therapeutic implications of germline vulnerabilities in DNA repair for precision oncology

DNA repair vulnerabilities are present in a significant proportion of cancers. Specifically, germline alterations in DNA repair not only increase cancer risk but are associated with treatment response and clinical outcomes. The therapeutic landscape of cancer has rapidly evolved with the FDA approval of therapies that specifically target DNA repair vulnerabilities. The clinical success of synthetic lethality between BRCA deficiency and poly(ADP-ribose) polymerase (PARP) inhibition has been truly revolutionary. Defective mismatch repair has been validated as a predictor of response to immune checkpoint blockade associated with durable responses and long-term benefit in many cancer patients. Advances in next generation sequencing technologies and their decreasing cost have supported increased genetic profiling of tumors coupled with germline testing of cancer risk genes in patients. The clinical adoption of panel testing for germline assessment in high-risk individuals has generated a plethora of genetic data, particularly on DNA repair genes. Here, we highlight the therapeutic relevance of germline aberrations in DNA repair to identify patients eligible for precision treatments such as PARP inhibitors (PARPis), immune checkpoint blockade, chemotherapy, radiation therapy and combined treatment. We also discuss emerging mechanisms that regulate DNA repair.

Practical and Scalable Manufacturing Process for the Key Intermediate of Poly(ADP-Ribose) Polymerase Inhibitor Olaparib

Olaparib (Lynparza) is a potent, highly selective inhibitor of poly(ADP-ribose)polymerase enzymes, approved by the U.S. FDA and EMA for the treatment of ovarian cancer. Herein, we report a practical, economical, and scalable process for the synthesis of 2-fluoro-5-((4-oxo-3,4-dihydrophthalazin-1-yl)methyl)benzoic acid, a key intermediate for olaparib. The low-cost industrial byproduct phthalhydrazide was used as the starting material to construct the phthalazinone moiety, which allowed access to the key intermediate by the Negishi coupling reaction. Optimization of each step has enabled the development of an environmentally benign and robust process with effective control of impurities.

Precision Medicine for BRCA/PALB2-Mutated Pancreatic Cancer and Emerging Strategies to Improve Therapeutic Responses to PARP Inhibition

Simple Summary

For the small subset of pancreatic ductal adenocarcinoma (PDAC) patients with loss-of-function mutations to BRCA1/2 or PALB2, both first-line and maintenance therapy differs significantly. These mutations confer a loss of double-strand break DNA homologous recombination (HR), substantially altering drug sensitivities. In this review, we discuss the current treatment guidelines for PDAC tumors deficient in HR, as well as newly emerging strategies to improve drug responses in this population. We also highlight additional patient populations in which these strategies may also be effective, and novel strategies aiming to confer similar drug sensitivity to tumors proficient in HR repair.

Abstract

Pancreatic cancer is projected to become the second leading cause of cancer-related death by 2030. As patients typically present with advanced disease and show poor responses to broad-spectrum chemotherapy, overall survival remains a dismal 10%. This underscores an urgent clinical need to identify new therapeutic approaches for PDAC patients. Precision medicine is now the standard of care for several difficult-to-treat cancer histologies. Such approaches involve the identification of a clinically actionable molecular feature, which is matched to an appropriate targeted therapy. Selective poly (ADP-ribose) polymerase (PARP) inhibitors such as Niraparib, Olaparib, Talazoparib, Rucaparib, and Veliparib are now approved for several cancers with loss of high-fidelity double-strand break homologous recombination (HR), namely those with deleterious mutations to BRCA1/2, PALB2, and other functionally related genes. Recent evidence suggests that the presence of such mutations in pancreatic ductal adenocarcinoma (PDAC), the most common and lethal pancreatic cancer histotype, significantly alters drug responses both with respect to first-line chemotherapy and maintenance therapy. In this review, we discuss the current treatment paradigm for PDAC tumors with confirmed deficits in double-strand break HR, as well as emerging strategies to both improve responses to PARP inhibition in HR-deficient PDAC and confer sensitivity to tumors proficient in HR repair.

Transposons: Unexpected players in cancer

Transposons are repetitive DNA sequences encompassing about half of the human genome. They play a vital role in genome stability maintenance and contribute to genomic diversity and evolution. Their activity is regulated by various mechanisms considering the deleterious effects of these mobile elements. Various genetic risk factors and environmental stress conditions affect the regulatory pathways causing alteration of transposon expression. Our knowledge of the biological role of transposons is limited especially in various types of cancers. Retrotransposons of different types (LTR-retrotransposons, LINEs and SINEs) regulate a plethora of genes that have a role in cell reprogramming, tumor suppression, cell cycle, apoptosis, cell adhesion and migration, and DNA repair. The regulatory mechanisms of transposons, their deregulation and different mechanisms underlying transposon-mediated carcinogenesis in humans focusing on the three most prevalent types, lung, breast and colorectal cancers, were reviewed. The modes of regulation employed include alternative splicing, deletion, insertion, duplication in genes and promoters resulting in upregulation, downregulation or silencing of genes.

Biomarkers of Central Nervous System Involvement from Epithelial Ovarian Cancer

Epithelial ovarian cancer (EOC) is the leading cause of death among women affected by gynaecological malignancies. Most patients show advanced disease at diagnosis (FIGO stage III-IV) and, despite the introduction of new therapeutic options, most women experience relapses. In most cases, recurrence is abdominal-pelvic; however, EOC can occasionally metastasize to distant organs, including the central nervous system. The incidence of brain metastases (BMs) from EOC is low, but it has grown over time; currently, there are no follow-up strategies available. In the last decade, a few biomarkers able to predict the risk of developing BMs from OC or as potential therapeutic targets have been investigated by several authors; to date, none have entered clinical practice. The purpose of this review is to offer a summary on the role of the most relevant predictors of central nervous system (CNS) involvement (hormone receptors; BRCA; MRD1; PD-1/PD-L1) and to highlight possible therapeutic strategies for the management of metastatic brain disease in EOC.

Inhibition of poly (ADP-Ribose) polymerase: A promising strategy targeting pancreatic cancer with BRCAness phenotype

The use of chemotherapeutic regimens for the treatment of pancreatic cancer is still limited because pancreatic cancer is usually diagnosed at an advanced stage as a refractory disease in which symptoms are difficult to recognize in the early stages. Furthermore, at advanced stages, there are important challenges to achieve clinical benefit and symptom resolution, even with the use of an expanded spectrum of anticancer drugs. Recently, a point of reduced susceptibility to conventional chemotherapies by breast cancer susceptibility gene (BRCA) mutations led to a new perspective for overcoming the resistance of pancreatic cancer within the framework of increased genome instability. Poly (ADP-Ribose) polymerase (PARP) -1 is an enzyme that can regulate intrinsic functions, such as response to DNA damage. Therefore, in an environment where germline mutations in BRCAs (BRCAness) inhibit homologous recombination in DNA damage, resulting in a lack of DNA damage response, a key role of PARP-1 for the adaptation of the genome instability could be further emphasized. Here, we summarized the key functional role of PARP-1 in genomic instability of pancreatic cancer with the BRCAness phenotype and listed clinical applications and outcomes of PARP-1 inhibitors to highlight the importance of targeting PARP-1 activity.

Inhibition of poly (ADP-Ribose) polymerase: A promising strategy targeting pancreatic cancer with BRCAness phenotype

The use of chemotherapeutic regimens for the treatment of pancreatic cancer is still limited because pancreatic cancer is usually diagnosed at an advanced stage as a refractory disease in which symptoms are difficult to recognize in the early stages. Furthermore, at advanced stages, there are important challenges to achieve clinical benefit and symptom resolution, even with the use of an expanded spectrum of anticancer drugs. Recently, a point of reduced susceptibility to conventional chemotherapies by breast cancer susceptibility gene (BRCA) mutations led to a new perspective for overcoming the resistance of pancreatic cancer within the framework of increased genome instability. Poly (ADP-Ribose) polymerase (PARP) -1 is an enzyme that can regulate intrinsic functions, such as response to DNA damage. Therefore, in an environment where germline mutations in BRCAs (BRCAness) inhibit homologous recombination in DNA damage, resulting in a lack of DNA damage response, a key role of PARP-1 for the adaptation of the genome instability could be further emphasized. Here, we summarized the key functional role of PARP-1 in genomic instability of pancreatic cancer with the BRCAness phenotype and listed clinical applications and outcomes of PARP-1 inhibitors to highlight the importance of targeting PARP-1 activity.

Homologous recombination proficiency in ovarian and breast cancer patients

Homologous recombination and DNA repair are important for genome maintenance. Genetic variations in essential homologous recombination genes, including BRCA1 and BRCA2 results in homologous recombination deficiency (HRD) and can be a target for therapeutic strategies including poly (ADP-ribose) polymerase inhibitors (PARPi). However, response is limited in patients who are not HRD, highlighting the need for reliable and robust HRD testing. This manuscript will review BRCA1/2 function and homologous recombination proficiency in respect to breast and ovarian cancer. The current standard testing methods for HRD will be discussed as well as trials leading to approval of PARPi's. Finally, standard of care treatment and synthetic lethality will be reviewed.

Importance of BRCA mutation for the current treatment of pancreatic cancer beyond maintenance

In this editorial, we comment on pancreatic cancer (PC), one of the most aggressive and lethal cancers. Only minimal improvements in survival rates have been achieved over recent years. Available chemotherapeutic regimens have little impact, and surgical resection remains the only reliable curative approach. We address current treatment options for these patients, focusing on the usefulness of breast cancer (BRCA) gene mutation as a prognostic biomarker and predictor of response to chemotherapy. Superior survival outcomes have been reported in patients with PC and mutant BRCA gene treated with first-line platinum-based chemotherapy. Therefore, it appears appropriate to include BRCA gene status among clinical criteria used to select the chemotherapy regimen. In addition, maintenance treatment with poly(ADP-ribose) polymerase inhibitors has been found to improve progression-free survival in patients with PC and mutated BRCA whose disease does not progress after first-line platinum-based chemotherapy. This combination has therefore been proposed as the optimal treatment regimen for these patients.

Making Connections: Integrative Signaling Mechanisms Coordinate DNA Break Repair in Chromatin

DNA double-strand breaks (DSBs) are hazardous to genome integrity and can promote mutations and disease if not handled correctly. Cells respond to these dangers by engaging DNA damage response (DDR) pathways that are able to identify DNA breaks within chromatin leading ultimately to their repair. The recognition and repair of DSBs by the DDR is largely dependent on the ability of DNA damage sensing factors to bind to and interact with nucleic acids, nucleosomes and their modified forms to target these activities to the break site. These contacts orientate and localize factors to lesions within chromatin, allowing signaling and faithful repair of the break to occur. Coordinating these events requires the integration of several signaling and binding events. Studies are revealing an enormously complex array of interactions that contribute to DNA lesion recognition and repair including binding events on DNA, as well as RNA, RNA:DNA hybrids, nucleosomes, histone and non-histone protein post-translational modifications and protein-protein interactions. Here we examine several DDR pathways that highlight and provide prime examples of these emerging concepts. A combination of approaches including genetic, cellular, and structural biology have begun to reveal new insights into the molecular interactions that govern the DDR within chromatin. While many questions remain, a clearer picture has started to emerge for how DNA-templated processes including transcription, replication and DSB repair are coordinated. Multivalent interactions with several biomolecules serve as key signals to recruit and orientate proteins at DNA lesions, which is essential to integrate signaling events and coordinate the DDR within the milieu of the nucleus where competing genome functions take place. Genome architecture, chromatin structure and phase separation have emerged as additional vital regulatory mechanisms that also influence genome integrity pathways including DSB repair. Collectively, recent advancements in the field have not only provided a deeper understanding of these fundamental processes that maintain genome integrity and cellular homeostasis but have also started to identify new strategies to target deficiencies in these pathways that are prevalent in human diseases including cancer.