Germline mutations of the DNA repair pathways in uterine serous carcinoma

Endometrial Cancer in a Family With RAD51D Gene Mutation

RAD51 complex plays an important role in homologous recombination deficiency and germline mutations have a well-documented association with breast and tubo-ovarian carcinoma, as well as serous-type endometrial carcinoma. We report a family of French Canadian ancestry with a germline mutation in RAD51D and two sisters presenting with endometrial carcinoma, endometrioid-type. The risk factors for endometrial adenocarcinoma, endometrioid-type are discussed in the context of the RAD51-associated carcinomas described to date.

BRCA 1/2 mutations and risk of uterine cancer: a systematic review and meta-analysis

PURPOSE

In this study, we aim to investigate the association between BRCA1/2 mutation and uterine cancer incidence.

MATERIAL AND METHOD

We systematically searched three databases including PubMed, Scopus, and Google Scholar up to August 2023; and reviewed 23 cohorts and cross-sectional studies to explore the association between BRCA1/2 mutations and uterine cancer incidence.

RESULTS

This systematic review comprised a total of 21 cohort studies and 2 cross-sectional studies after the screening process. According to meta-analysis the prevalence of the BRCA1/2 gene in patients with uterine cancer was 0.02 (95%CI = [0.01,0.03], P < 0.01, I2 = 94.82%) CONCLUSIONS: Our meta-analysis investigates a 2% prevalence of BRCA1/2 mutation in patients with uterine cancer. Patients with BRCA1/2 mutations might be more conscious of uterine malignancies.

Comparison of clinical characteristics and prognosis in endometrial carcinoma with different pathological types: a retrospective population-based study

BACKGROUND

Endometrial carcinoma (EC) is the second most common gynecological malignancy, and the differences between different pathological types are not entirely clear. Here, we retrospectively collected eligible EC patients to explore their differences regarding clinical characteristics and prognosis.

METHODS

Five hundred seventy EC patients from the First Affiliated Hospital of Zhengzhou University were included. Prognostic factors were measured using the univariate/multivariate Cox models. Overall survival (OS) and progression-free survival (PFS) were the primary and secondary endpoints, respectively.

RESULTS

In total, 396 patients with uterine endometrioid carcinoma (UEC), 106 patients with uterine serous carcinoma (USC), 34 patients with uterine mixed carcinoma (UMC), and 34 patients with uterine clear cell carcinoma (UCCC) were included. Comparison of baseline characteristics revealed patients diagnosed with UEC were younger, had more early clinical stage, and had lower incidence of menopause and lymph node metastasis. Compared to UEC, other pathological EC obtained more unfavorable OS (UCCC: HR = 12.944, 95%CI = 4.231-39.599, P < 0.001; USC: HR = 5.958, 95%CI = 2.404-14.765, P < 0.001; UMC: HR = 1.777, 95%CI = 0.209-15.114, P = 0.599) and PFS (UCCC: HR = 8.696, 95%CI = 1.972-38.354, P = 0.004; USC: HR = 4.131, 95%CI = 1.243-13.729, P = 0.021; UMC: HR = 5.356, 95%CI = 0.935-30.692, P = 0.060). Compared with UEC patients, the OS of UCCC patients in stage I-II and USC patients in stage III-IV were significantly worse, while UMC patients in stage I-II favored poorer PFS. The OS of UCCC patients receiving no postoperative adjuvant therapy or chemotherapy alone were significantly worse.

CONCLUSIONS

The baseline characteristics of UEC and other rare EC types varied greatly, and the prognostic significance of different pathological types on EC patients depended on clinical tumor stages and therapeutic options.

ATM mutation in aggressive uterine adenosarcoma in which systemic chemotherapies had remarkable effects

Uterine adenosarcoma is a rare gynecologic malignancy, and 10-25% of the cases exhibit clinically aggressive behaviors. Although TP53 mutations are frequently identified in high-grade adenosarcomas of the uterus, definitive gene alterations have not been identified in uterine adenosarcomas. Specifically, no reports have described mutations in homologous recombination deficiency-related genes in uterine adenosarcomas. This study presents a case of uterine adenosarcoma without sarcomatous overgrowth but with TP53 mutation that exhibited clinically aggressive behaviors. The patient had an ATM mutation, which is a gene associated with homologous recombination deficiency, and exhibited a good response against platinum-based chemotherapy and possible therapeutic target by poly(ADP-ribose) polymerase inhibitors.

Homologous Recombination Repair Mechanisms in Serous Endometrial Cancer

Simple Summary

Serous endometrial cancer is an unusual and aggressive endometrial cancer subtype, conferring the highest mortality of all endometrial cancers. In many ways, it resembles the more common tumor entity high-grade serous ovarian cancer. Thus, there is an urgent need for better treatment options for serous endometrial cancer patients. It is crucial for all dividing cells that the DNA repair is functioning correctly. Our aim was to investigate deficiencies in DNA repair in serous endometrial cancer, in particular the presence of homologous recombination repair deficiency. This kind of DNA repair defect may indicate that a specific targeted therapy, so-called PARP inhibitors, which are already in use for the treatment of ovarian cancer, may be useful also in serous endometrial cancer. This study contributes to the largely unexplored field of DNA repair deficiencies in serous endometrial cancer, and may hence contribute to future improved prognosis for these patients.

Abstract

Serous endometrial cancer (SEC) resembles high-grade serous ovarian cancer (HGSOC) genetically and clinically, with recurrent copy number alterations, TP53 mutations and a poor prognosis. Thus, SEC patients may benefit from targeted treatments used in HGSOC, e.g., PARP inhibitors. However, the preclinical and clinical knowledge about SEC is scarce, and the exact role of defective DNA repair in this tumor subgroup is largely unknown. We aimed to outline the prevalence of homologous recombination repair deficiency (HRD), copy-number alterations, and somatic mutations in SEC. OncoScan SNP arrays were applied to 19 tumors in a consecutive SEC series to calculate HRD scores and explore global copy-number profiles and genomic aberrations. Copy-number signatures were established and targeted sequencing of 27 HRD-associated genes was performed. All factors were examined in relation to HRD scores to investigate potential drivers of the HRD phenotype. Ten of the 19 SEC tumors (53%) had an HRD score > 42, considered to reflect an HRD phenotype. Higher HRD score was associated with loss of heterozygosity in key HRD genes, and copy-number signatures associated with non-BRCA1/2 dependent HRD in HGSOC. A high number of SECs display an HRD phenotype. It remains to be elucidated whether this also confers PARP inhibitor sensitivity.

Uterine serous carcinoma: Molecular features, clinical management, and new and future therapies

Uterine serous carcinoma (USC) is an aggressive subtype of endometrial cancer. Multimodality treatment with surgery, radiotherapy, and chemotherapy is commonly used, given its propensity for extrauterine spread, distant recurrences, and poor prognosis. However, the use of molecularly-based therapy is expanding. Here, we review key molecular features of USC, discuss current management, and assess the landscape of novel therapies and combinations.

MRE11-RAD50-NBS1 complex alterations and DNA damage response: implications for cancer treatment

Genome instability is a hallmark of cancer cells and can be accelerated by defects in cellular responses to DNA damage. This feature of malignant cells opens new avenues for tumor targeted therapy. MRE11-RAD50-NBS1 complex plays a crucial role in sensing and repair of DNA damage. Through interacting with other important players of DNA damage response, MRE11-RAD50-NBS1 complex is engaged in various DNA damage repair pathways. Mutations in any member of this complex may lead to hypersensitivity to genotoxic agents and predisposition to malignancy. It is assumed that the defects in the complex may contribute to tumorigenesis and that treatments targeting the defect may be beneficial to cancer patients. Here, we summarized the recent research findings of the role of MRE11-RAD50-NBS1 complex in tumorigenesis, cancer treatment and discussed the potential approaches of targeting this complex to treat cancer.

Prevalence of Homologous Recombination-Related Gene Mutations Across Multiple Cancer Types

Purpose

The prevalence of homologous recombination DNA damage repair (HR-DDR) deficiencies among all tumor lineages is not well characterized. Therapy directed toward homologous recombination DDR deficiency (HRD) is now approved in ovarian and breast cancer, and there may be additional opportunities for benefit for patients with other cancers. Comprehensive evaluations for HRD are limited in part by the lack of a uniform, cost-effective method for testing and defining HRD.

Methods

Molecular profiles of 52,426 tumors were reviewed to identify pathogenic mutations in the HR-DDR genes ARID1A, ATM, ATRX, BAP1, BARD1, BLM, BRCA1/2, BRIP1, CHEK1/2, FANCA/C/D2/E/F/G/L, MRE11A, NBN, PALB2, RAD50, RAD51, RAD51B, or WRN. From solid tumors submitted to Caris Life Sciences, molecular profiles were generated using next-generation sequencing (NGS; average read depth, 500×). A total of 17,566 tumors were sequenced with NGS600 (n = 592 genes), and 34,860 tumors underwent hotspot Illumina MiSeq platform testing (n = 47 genes).

Results

Of the tumors that underwent NGS600 testing, the overall frequency of HRDDR mutations detected was 17.4%, and the most commonly mutated lineages were endometrial (34.4%; n = 1,475), biliary tract (28.9%; n = 343), bladder (23.9%; n = 201), hepatocellular (20.9%; n = 115), gastroesophageal (20.8%; n = 619), and ovarian (20.0%; n = 2,489). Least commonly mutated lineages included GI stromal (3.7%; n = 108), head and neck (6.8%; n = 206), and sarcoma (9.3%; n = 592). ARID1A was the most commonly mutated gene (7.2%), followed by BRCA2 (3.0%), BRCA1 (2.8%), ATM (1.3%), ATRX (1.3%), and CHEK2 (1.3%).

Conclusions

HR-DDR mutations were seen in 17.4% of tumors across 21 cancer lineages, providing a path to explore the role of HRD-directed therapies, including poly-ADP ribose polymerase inhibitors, DNA-damaging chemotherapies, and newer agents such as ATR inhibitors.

The relationship between the PD-1/PD-L1 pathway and DNA mismatch repair in cervical cancer and its clinical significance

Background

According to recent clinical observations, deficient DNA mismatch repair (dMMR) is capable of improving antitumor effects of the PD-1/PD-L1 pathway, suggesting that dMMR may act as a prognostic indicator of PD-1/PD-L1 antibody drugs. In this study, we examined the dMMR and PD-1/PD-L1 expression, as well as explored the correlation of dMMR status with PD-1/PD-L1 expression in cervical cancer patients, in order to optimize cervical cancer patient selection for PD-1/PD-L1 antibody drug treatment, which is helpful to avoid adverse effects and keep costs manageable.

Methods

Sixty-six tissue samples from patients with squamous cell carcinoma were collected, and data of their clinical characteristics were also gathered. Based on these samples, the expression levels of MLH1, MSH2, and PD-L1 in cancer cells were tested by immunohistochemical assay (IHC). Moreover, PD-1/PD-L1 expression in tumor-invading lymphocytes (TILs) was detected by IHC as well. Six single-nucleotide-repeat markers of microsatellite instability (MSI), including NR-27, MONO-27, BAT-25, NR-24, NR-21, and BAT-26, were tested by capillary electrophoresis sequencer analysis. According to expression of MLH1, MSH2 and the MSI test, all 66 cases were divided into dMMR or proficient DNA mismatch repair (pMMR) groups. The comparisons of dMMR and PD-L1 in cancer cells and of PD-1/PD-L1 in TILs were conducted categorized by age, childbearing history, history of abortion, ethnicity, and cancer cell differentiation subgroup. Furthermore, PD-L1 levels in cancer cells and PD-1/PD-L1 in TILs were analyzed and compared in both dMMR and pMMR subgroups.

Results

Of the patient samples, 25.8% were associated with dMMR. PD-L1 in cancer cells, PD-L1 in TILs, and PD-1 in TILs took up 59.1%, 47.0%, and 60.6%, respectively. The data indicated that both dMMR and PD-L1 overexpression resulted from lower cancer differentiation, more incidences of childbearing, and a history of abortion. Abortion could significantly increase PD-1 expression levels in TILs. Additionally, more incidence of childbearing or older age (35–55 years) was able to upregulate PD-L1 expression in TILs. Statistical difference of PD-L1 in cancer cells could be observed between dMMR and pMMR subgroups. In the dMMR group, PD-L1 in cancer cells and PD-1 in TILs had no correlation (r_s=0.161, p=0.537), but in the pMMR group, they had good correlation (r_s=0.645, p<0.001).

Conclusion

According to prior studies and our own experiments, PD-L1 in both cancer cells and TILs and PD-1 in TILs are widely observed in cervical cancer patients, indicating that there may be potential to apply PD-1/PD-L1 antibody drugs in cervical cancer. dMMR patients are associated with higher PD-L1 expression compared with pMMR ones, which suggested that PD-1/PD-L1 antibody drugs may work well in dMMR cervical cancer patients. Moreover, in patients with more incidences of childbearing or abortion, dMMR may be a molecular detection target for clinical application of PD-1/PD-L1 antibody drugs.

Therapeutic targeting and patient selection for cancers with homologous recombination defects

INTRODUCTION

DNA double-strand breaks (DSBs) are toxic DNA lesions that can be repaired by non-homologous end-joining (NHEJ) or homologous recombination (HR). Mutations in HR genes elicit a predisposition to cancer; yet, they also result in increased sensitivity to certain DNA damaging agents and poly (ADP-ribose) polymerase (PARP) inhibitors. To optimally implement PARP inhibitor treatment, it is important that patients with HR-deficient tumors are adequately selected. Areas covered: Herein, the authors describe the HR pathway mechanistically and review the treatment of HR-deficient cancers, with a specific focus on PARP inhibition for BRCA1/2-mutated breast and ovarian cancer. In addition, mechanisms of acquired PARP inhibitor resistance are discussed. Furthermore, combination therapies with PARP inhibitors are reviewed, in the context of both HR-deficient and HR-proficient tumors and methods for proper patient selection are also discussed. Expert opinion: Currently, only patients with germline or somatic BRCA1/2 mutations are eligible for PARP inhibitor treatment and only a proportion of patients respond. Patients with HR-deficient tumors caused by other (epi)genetic events may also benefit from PARP inhibitor treatment. Ideally, selection of eligible patients for PARP inhibitor treatment include a functional HR read-out, in which cancer cells are interrogated for their ability to perform HR repair and maintain replication fork stability.

Major clinical research advances in gynecologic cancer in 2016: 10-year special edition

In 2016, 13 topics were selected as major research advances in gynecologic oncology. For ovarian cancer, study results supporting previous ones regarding surgical preventive strategies were reported. There were several targeted agents that showed comparable responses in phase III trials, including niraparib, cediranib, and nintedanib. On the contrary to our expectations, dose-dense weekly chemotherapy regimen failed to prove superior survival outcomes compared with conventional triweekly regimen. Single-agent non-platinum treatment to prolong platinum-free-interval in patients with recurrent, partially platinum-sensitive ovarian cancer did not improve and even worsened overall survival (OS). For cervical cancer, we reviewed robust evidences of larger-scaled population-based study and cost-effectiveness of nonavalent vaccine for expanding human papillomavirus (HPV) vaccine coverage. Standard of care treatment of locally advanced cervical cancer (LACC) was briefly reviewed. For uterine corpus cancer, new findings about appropriate surgical wait time from diagnosis to surgery were reported. Advantages of minimally invasive surgery over conventional laparotomy were reconfirmed. There were 5 new gene regions that increase the risk of developing endometrial cancer. Regarding radiation therapy, Post-Operative Radiation Therapy in Endometrial Cancer (PORTEC)-3 quality of life (QOL) data were released and higher local control rate of image-guided adaptive brachytherapy was reported in LACC. In addition, 4 general oncology topics followed: chemotherapy at the end-of-life, immunotherapy with reengineering T-cells, actualization of precision medicine, and artificial intelligence (AI) to make personalized cancer therapy real. For breast cancer, adaptively randomized trials, extending aromatase inhibitor therapy, and ribociclib and palbociclib were introduced.

Linking uterine serous carcinoma to BRCA1/2-associated cancer syndrome: A meta-analysis and case report

BACKGROUND

Uterine serous carcinoma (USC) shows greater morphological, clinical and molecular similarities to high-grade ovarian tubal serous carcinoma than to other types of endometrial cancer. As high-grade ovarian tubal serous carcinoma is known to be associated with BRCA1/2 pathogenic germline mutations (PMs), we aimed to explore whether USC is also a constituent of hereditary breast and ovarian cancer syndrome.

METHODS

Pubmed, EMBASE and Web of Science were searched in July 2016 for articles assessing the association between USC and germline BRCA1/2-PMs. Pooled analysis and comparisons were performed using a random effects logistic model, stratifying for ethnicity (Ashkenazi versus non-Ashkenazi). In addition, tumour tissue from an USC case with a hereditary BRCA1-PM was analysed for loss of heterozygosity at the BRCA1 locus and was functionally analysed for homologous recombination proficiency.

RESULTS

The search yielded 1893 citations, 10 studies were included describing 345 USC patients. For Ashkenazi Jews, the pooled odds ratio of having a germline BRCA1/2-PM was increased in USC patients compared with the general Ashkenazi population: odds ratio 5.4 (95%confidence interval: 2.2-13.1). In the patient with USC, we identified the known germline BRCA1-PM in the tumour DNA. Furthermore, we showed both loss of heterozygosity of the wild-type allele and a deficiency of homologous recombination.

CONCLUSION

This study suggests that USC may be an overlooked component of BRCA1/2-associated hereditary breast and ovarian cancer syndrome. Screening for germline BRCA1/2-PMs should be considered in patients diagnosed with USC, especially in cases with a positive first-degree family history for breast and/or ovarian cancer.