Takashi Kohno

TP53 gene and pathway alterations in gastric-type adenocarcinoma of the cervix

Abstract Background Human papillomavirus infection contributes to the development of almost all cervical malignancies, aside from gastric-type adenocarcinoma of the cervix, a rare aggressive subtype without human papillomavirus infection. Methods To address the carcinogenic mechanism of this disease, we performed a comparative multi-omics analysis of gastric-type adenocarcinoma of the cervix and usual-type endocervical adenocarcinoma in 3 independent cohorts of patients with gastric-type adenocarcinoma of the cervix and usual-type endocervical adenocarcinoma. The first cohort comprised 8 gastric-type adenocarcinoma of the cervix and 22 patients with usual-type endocervical adenocarcinoma treated at the National Cancer Center Hospital between 2002 and 2020, who were examined by targeted and whole transcriptome sequencing. The other 2 cohorts comprised 52 patients with gastric-type adenocarcinoma of the cervix and 109 patients with usual-type endocervical adenocarcinoma and 39 patients with gastric-type adenocarcinoma of the cervix and 232 patients with usual-type endocervical adenocarcinoma, whose mutational data were obtained from the Center for Cancer Genomics and Advanced Therapeutics (Japanese patients) and Genomics Evidence Neoplasia Information Exchange (US patients) public databases, respectively. Metabolomic analysis was performed in 8 patients, including 5 with gastric-type adenocarcinoma of the cervix. Results TP53 mutations were more prevalent in gastric-type adenocarcinoma of the cervix than in usual-type endocervical adenocarcinoma in all 3 cohorts. Transcriptome analysis consistently revealed frequent suppression of TP53-related pathways in gastric-type adenocarcinoma of the cervix. Metabolites preferentially detected in gastric-type adenocarcinoma of the cervix tissues suggest TP53 alterations are implicated in intratumoral metabolic properties. Conclusion The development of gastric-type adenocarcinoma of the cervix is likely driven by TP53 mutations, which play a large role in shaping intracellular signaling and metabolic profiles within tumor cells.

Prevalence and outcomes of germline pathogenic variants of homologous recombination repair genes in ovarian cancer

AbstractGermline pathogenic variants (PVs) are pivotal in gynecological oncology. We focused on the prevalence, clinicopathological features, and survival impact of homologous recombination repair (HRR) PVs in patients with epithelial ovarian cancer (EOC). This was a multicenter retrospective cohort study, and 1248 patients with EOC were registered. Eligible patients (n = 1112) underwent germline DNA analysis for 26 cancer predisposition genes, including nine HRR‐related genes, such as BRCA1/2, BRIP1, PALB2, RAD51C/D, and ATM. The associations between clinicopathological factors and HRR‐related PVs were examined. Kaplan–Meier and Cox regression analyses were conducted. Among 1091 analyzed patients, 153 (14.0%) carried PVs and 140 (12.8%) were HRR‐related. HRR‐PV‐positive status significantly correlated with serous carcinoma (22.9% vs. 4.8%, P < 0.0001) and advanced disease (18.5% vs. 5.9%, P < 0.0001). The HRR‐PV‐positive group exhibited higher prevalence of personal breast (12.9%) and familial breast/ovarian (29.2%) cancer history. HRR status independently improved overall survival in stage III/IV disease (P = 0.04) but not progression‐free survival. HRR‐related germline PVs exhibit distinct clinicopathological features with survival implications. Variants were significantly associated with serous carcinoma and advanced disease, underscoring the importance of genetic testing to develop individualized EOC treatment strategies. Considering the study period (2000–2019), the limited use of bevacizumab and poly (ADP‐ribose) polymerase inhibitors as maintenance therapy should be recognized.

Clinical features and impact of p53 status on sporadic mismatch repair deficiency and Lynch syndrome in uterine cancer

AbstractThe clinical features of sporadic mismatch repair deficiency (MMRd) and Lynch syndrome (LS) in Japanese patients with endometrial cancer (EC) were examined by evaluating the prevalence and prognostic factors of LS and sporadic MMRd in patients with EC. Targeted sequencing of five LS susceptibility genes (MLH1, MSH2, MSH6, PMS2, and EPCAM) was carried out in 443 patients with EC who were pathologically diagnosed with EC at the National Cancer Center Hospital between 2011 and 2018. Pathogenic variants in these genes were detected in 16 patients (3.7%). Immunohistochemistry for MMR proteins was undertaken in 337 of the 433 (77.9%) EC patients, and 91 patients (27.0%) showed absent expression of at least one MMR protein. The 13 cases of LS with MMR protein loss (93.8%) showed a favorable prognosis with a 5‐year overall survival (OS) rate of 100%, although there was no statistically significant difference between this group and the sporadic MMRd group (p = 0.27). In the MMRd without LS group, the 5‐year OS rate was significantly worse in seven patients with an aberrant p53 expression pattern than in those with p53 WT (53.6% vs. 93.9%, log‐rank test; p = 0.0016). These results suggest that p53 abnormalities and pathogenic germline variants in MMR genes could be potential biomarkers for the molecular classification of EC with MMRd.