ARID1A Regulates Progesterone Receptor Expression in Early Endometrial Endometrioid Carcinoma Pathogenesis

ARID1A in Gynecologic Precancers and Cancers

The highest frequency of genetic alterations in the tumor suppressor ARID1A occurs in malignancies of the female reproductive tract. The prevalence of ARID1A alterations in gynecologic precancers and cancers is summarized from the literature, and the putative mechanisms of tumor suppressive action examined both in benign/precursor lesions including endometriosis and atypical hyperplasia and in malignancies of the ovary, uterus, cervix and vagina. ARID1A alterations in gynecologic cancers are usually loss-of-function mutations, resulting in diminished or absent protein expression. ARID1A deficiency results in pleiotropic downstream effects related not only to its role in transcriptional regulation as a SWI/SNF complex subunit, but also related to the functions of ARID1A in DNA replication and repair, immune modulation, cell cycle progression, endoplasmic reticulum (ER) stress and oxidative stress. The most promising actionable signaling pathway interactions and therapeutic vulnerabilities of ARID1A mutated cancers are presented with a critical review of the currently available experimental and clinical evidence. The role of ARID1A in response to chemotherapeutic agents, radiation therapy and immunotherapy is also addressed. In summary, the multi-faceted role of ARID1A mutation in precancer and cancer is examined through a clinical lens focused on development of novel preventive and therapeutic interventions for gynecological cancers.

EPPK1 as a Prognostic Biomarker in Type I Endometrial Cancer and Its Correlation with Immune Infiltration

Purpose

Approximately 20% of patients with type I endometrial cancer (EC) of the uterus experience recurrence and metastasis. However, existing data do not provide sufficient evidence for the utility of protein levels as prognostic biomarkers in type I EC. This study aims to determine whether epiplakin1 (EPPK1) and progesterone receptor (PR) play a role in the recurrence and metastasis of type I EC.

Methods

Following the Reporting Recommendations for Tumor Marker Prognostic Studies (REMARK) for assessing the quality of biomarker research results, a retrospective analysis was conducted on clinical information and tissue samples of type I EC patients. Protein expression data and clinical data for type I EC were downloaded from The Cancer Proteome Atlas (TCPA) database. We utilized the Kaplan-Meier (K-M) method and Cox proportional hazards regression analyses to evaluate whether epiplakin1 (EPPK1), progesterone receptor (PR) and certain clinical parameters can serve as independent prognostic factors. The Immune Cell Abundance Identifier (ImmuCellAI) and Cancer Immunome Atlas (TCIA) were employed to predict responses to immunotherapy. Immunohistochemistry was carried out to assess the expression of EPPK1 in type I EC.

Results

Type I EC patients with high EPPK1 and low PR expression had higher International Federation of Gynecology and Obstetrics (FIGO) stage, recurrence, and metastasis rates. Furthermore, EPPK1 was identified as an independent prognostic factor, and low expression of EPPK1 was predominantly observed in the POLE ultramutated (POLEmut) group, indicating a favorable prognosis. Additionally, the high EPPK1 expression group had a lower Immune Prognostic Score (IPS), suggesting that the high-expression group may not benefit from immune checkpoint inhibitors.

Conclusion

High expression of EPPK1 is an independent prognostic factor in type I EC patients with low PR expression. It can identify a subgroup of patients at high risk of recurrence. A more aggressive treatment approach is recommended for these patients.

The Role of the AT-Rich Interaction Domain 1A Gene (ARID1A) in Human Carcinogenesis

The switch/sucrose non-fermentable (SWI/SNF) (SWI/SNF) complex uses energy from ATP hydrolysis to mobilise nucleosomes on chromatin. Components of SWI/SNF are mutated in 20% of all human cancers, of which mutations in AT-rich binding domain protein 1A (ARID1A) are the most common. ARID1A is mutated in nearly half of ovarian clear cell carcinoma and around one-third of endometrial and ovarian carcinomas of the endometrioid type. This review will examine in detail the molecular functions of ARID1A, including its role in cell cycle control, enhancer regulation, and the prevention of telomerase activity. ARID1A has key roles in the maintenance of genomic integrity, including DNA double-stranded break repair, DNA decatenation, integrity of the cohesin complex, and reduction in replication stress, and is also involved in mismatch repair. The role of ARID1A loss in the pathogenesis of some of the most common human cancers is discussed, with a particular emphasis on gynaecological cancers. Finally, several promising synthetic lethal strategies, which exploit the specific vulnerabilities of ARID1A-deficient cancer cells, are briefly mentioned.

Genomic profile of Chinese patients with endometrial carcinoma

BACKGROUNDS

Endometrial carcinoma (EC) is one of the most commonly diagnosed gynecologic malignancy in China. However, the genetic profile of Chinese EC patients has not been well established yet.

METHODS

In current study, 158 Chinese EC patients were subjected to next-generation sequencing assay (74 took testing of EC-related 20-genes panel, and 84 took the expanded panel). Of the 158 patients, 91 patients were performed germline mutation testing using the expanded panel. Moreover, the public datasets from TCGA and MSKCC were utilized to compare the genomic differences between Chinese and Western EC patients. The proteomic and transcriptomic from CPTAC and TCGA were derived and performed unsupervised clustering to identify molecular subtypes.

RESULTS

Among the 158 patients analyzed, a significant majority (85.4%) exihibited at least one somatic alteration, with the most prevalent alterations occurring in PTEN, PIK3CA, TP53, and ARID1A. These genomic alterations were mainly enriched in the PI3K, cell cycle, RAS/RAF/MAPK, Epigenetic modifiers/Chromatin remodelers, and DNA damage repair (DDR) signaling pathways. Additionally, we identified ten individuals (11.0%) with pathogenic or likely pathogenic germline alterations in seven genes, with the DDR pathway being predominantly involved. Compared to Western EC patients, Chinese EC patients displayed different prevalence in AKT1, MET, PMS2, PIK3R1, and CTCF. Notably, 69.6% of Chinese EC patients were identified with actionable alterations. In addition, we discovered novel molecular subtypes in ARID1A wild-type patients, characterized by an inferior prognosis, higher TP53 but fewer PTEN and PIK3CA alterations. Additionally, this subtype exhibited a significantly higher abundance of macrophages and activated dendritic cells.

CONCLUSION

Our study has contributed valuable insights into the unique germline and somatic genomic profiles of Chinese EC patients, enhancing our understanding of their biological characteristics and potential therapeutic avenues. Furthermore, we have highlighted the presence of molecular heterogeneity in ARID1A-wild type EC patients, shedding light on the complexity of this subgroup.