Ayumi Taguchi

DNA Methylation in Ovarian and Endometrial Cancers: Predictive and Mechanistic Roles in PARP Inhibitor and ICI Response

ABSTRACT Cancer treatment is shifting from an organ‐based approach to one driven by biological phenotypes, emphasizing the need to understand molecular mechanisms. DNA methylation plays a pivotal role in tumor biology, not only through gene silencing but also by inducing distinct behaviors beyond genetic mutations. In gynecologic cancers, molecular diagnostics, such as homologous recombination deficiency status guiding poly(ADP‐ribose) polymerase (PARP) inhibitor therapy in ovarian cancer and deficient mismatch repair/microsatellite instability‐high status informing immune checkpoint inhibitor (ICI) therapy in endometrial cancer have already been used in clinical practice. However, tumors with epigenetically driven functional deficiencies, such as BRCA1 promoter methylation in homologous recombination‐deficient ovarian cancers or MLH1 promoter methylation in deficient mismatch repair/microsatellite instability‐high endometrial cancers, often exhibit poorer prognoses and reduced therapeutic responses compared to their genetically mutated counterparts. Given the unique impact of DNA methylation, precise detection is crucial. Integrating methylation analysis into molecular classification could refine diagnostics—both by identifying mechanistic contributors to treatment response and by serving as predictive biomarkers for therapy selection—thereby optimizing patient management. This review explores the role of DNA methylation in modulating responses to PARP inhibitors and ICIs, highlights its promise as a biomarker in precision oncology, and outlines current developments and clinical challenges in BRCA1 and MLH1 methylation assays.

Optimizing treatment for platinum‐resistant ovarian clear cell carcinoma: Efficacy of gemcitabine and combination therapy with bevacizumab

AbstractBackgroundPlatinum‐resistant (PR) ovarian clear cell carcinoma (OCCC) is highly resistant to chemotherapy and has a poor prognosis. Both in‐vitro and clinical studies have suggested that gemcitabine (GEM) is particularly effective against OCCC. Moreover, a combination with bevacizumab (Bev) is expected to enhance the efficacy of chemotherapy.MethodsTo clarify these effects, the authors conducted a multicenter, retrospective cohort study of 130 patients who received treatment single‐agent chemotherapy, with or without Bev, for PR‐OCCC. The effects of loss of AT‐rich interaction domain 1A (ARID1A) protein expression also were assessed.ResultsPatients who received GEM as their first regimen achieved better overall survival (OS) than those who received other agents (median OS, 15.2 vs. 11.0 months; hazard ratio [HR], 0.64; 95% confidence interval [CI], 0.41–0.96; p = .032). Bev combination therapies demonstrated a significantly improved time to treatment failure compared with chemotherapy alone (6.6 vs. 2.7 months; HR, 0.61; 95% CI, 0.41–0.87; p = .009) and showed a trend toward longer OS (23.3 vs. 9.8 months; HR, 0.62; 95% CI, 0.34–1.05; p = .085). ARID1A status did not affect OS in the overall group or in the group that received GEM as the first‐line regimen (p = .41 and p = .31, respectively).ConclusionsCollectively, the current findings suggest that GEM, particularly as a first‐line treatment, may improve the prognosis of patients with PR‐OCCC. Moreover, Bev combination therapy is a promising option for treating PR‐OCCC.

BRCA1 Promoter Methylation in Ovarian Cancer: Clinical Relevance and a Novel Diagnostic Approach Using Fragment Analysis

ABSTRACTHomologous recombination deficiency (HRD) tests, including MyChoice CDx, are companion diagnostics for poly (ADP‐ribose) polymerase (PARP) inhibitors. BRCA1 promoter hypermethylation, a major HRD cause, may correlate with poorer prognosis. This study aimed to develop a simple, accurate method for detecting BRCA1 promoter hypermethylation and elucidate the characteristics of such cases. BRCA1 promoter methylation was analyzed using bisulfite sequencing (BIS‐seq) in high‐grade serous ovarian carcinoma specimens. We developed a newly developed BRCA1 methylation assay, BRCA1‐Fragment Analysis of Methylation (BRCA1‐FAM), which combines restriction enzyme digestion with fragment analysis. The accuracy of this assay was compared to the results of BIS‐seq. We evaluated the relationship between BRCA1 promoter hypermethylation and prognosis and examined its association with BRCA1 expression and loss of heterozygosity. BRCA1 mutations and promoter methylation were mutually exclusive in the analyzed cases, with methylation observed in 28.9% (22/76) of primary debulking surgery cases. The BRCA1‐FAM showed high sensitivity (91.3%) and specificity (100%) for detecting BRCA1 promoter hypermethylation, comparable to BIS‐seq. Cases with BRCA1 promoter hypermethylation had significantly poorer progression‐free survival (log‐rank test, p = 0.048). Among these cases, 86.4% displayed abnormal BRCA1 immunostaining, with lower frequencies of BRCA1 loss of heterozygosity compared to those of other groups. BRCA1 promoter hypermethylation is associated with poor prognosis, underscoring the importance of its identification for HRD stratification. BRCA1‐FAM is a simple and highly accurate method for evaluating BRCA1 promoter methylation. This approach may potentially enhance the precision of personalized therapies for ovarian cancer.

Prognosis of patients with endometrial cancer or atypical endometrial hyperplasia after complete remission with fertility-sparing therapy

Abstract Purpose Although many patients with endometrial cancer (EC) or atypical endometrial hyperplasia (AEH) achieve complete remission (CR) after high-dose medroxyprogesterone acetate (MPA) treatment, no consensus has been reached on management after CR. Currently, patients receive estrogen-progestin maintenance therapy, but no recommendations exist regarding the duration of maintenance therapy or whether hysterectomy should be considered. This study aimed to provide insights into the management of EC/AEH after achieving CR. Methods We retrospectively investigated the prognosis of 50 patients with EC or AEH who achieved CR after MPA therapy. We assessed the association between disease recurrence and clinicopathological features and the pre- and post-operative histological diagnoses of patients who underwent hysterectomy. Results The median follow-up duration was 34 months (range: 1–179 months). Recurrence was observed in 17 patients. Among the clinical characteristics investigated, only the primary disease was significantly associated with disease recurrence; patients with EC had a higher risk of recurrence than those with AEH (p = 0.037). During the observation period, 27 patients attempted pregnancy, and 14 pregnancies resulted in delivery. Patients who gave birth had significantly longer relapse-free survivals than those who did not (p = 0.031). Further, 16 patients underwent hysterectomies, and AEH was detected postoperatively in 4 of 11 patients (36.4%) with no preoperative abnormalities. Conclusions We identified several clinical features of patients with EC and AEH after CR. Given the high probability of endometrial abnormalities detected postoperatively, hysterectomy may be considered for patients who no longer want children.

Impact of human papillomavirus types on uterine cervical neoplasia

AbstractHuman papillomavirus (HPV) is a major cause of cervical cancer. As the natural history of HPV‐associated cervical lesions is HPV genotype‐dependent, it is important to understand the characteristics of these genotypes and to manage them accordingly. Among high‐risk HPVs, HPV16 and 18 are particularly aggressive, together accounting for 70% of HPV genotypes detected in cervical cancer. Other than HPV16 and 18, HPV31, 33, 35, 45, 52, and 58 are also at a high risk of progression to cervical intraepithelial neoplasia (CIN)3 or higher. Recent studies have shown that the natural history of HPV16, 18, 52, and 58, which are frequently detected in Japan, depends on the HPV genotype. For example, HPV16 tends to progress in a stepwise fashion from CIN1 to CIN3, while HPV52 and 58 are more likely to persist in the CIN1 to CIN2 state. Among the high‐risk HPVs, HPV18 has some peculiar characteristics different from those of other high‐risk HPV types; the detection rate in precancerous lesions is much lower than those of other high‐risk HPVs, and it is frequently detected in highly malignant adenocarcinoma and small cell carcinoma. Recent findings demonstrate that HPV18 may be characterized by latent infection and carcinogenesis in stem cell‐like cells. In this context, this review outlines the natural history of HPV‐infected cervical lesions and the characteristics of each HPV genotype.

Heterogeneous effects of cytotoxic chemotherapies for platinum-resistant ovarian cancer

Abstract Background Single-agent chemotherapy with or without bevacizumab (Bev) is a standard therapy for platinum-resistant ovarian cancer (PR-OC). However, there is a lack of literature on chemotherapy agent selection in heterogenous PR-OC. Therefore, we aimed to clarify the heterogeneous treatment effects of each chemotherapy agent. Methods Patients who underwent single-drug chemotherapy agents or Bev combination therapy for PR-OC between January 2009 and June 2022 were included in this study. We assessed the impact of each chemotherapy agent on the time to treatment failure (TTF) according to histological type, platinum-free interval (PFI), and Bev usage. Results A total of 158 patients received 343 different chemotherapy regimens. In patients with clear cell carcinoma/mucinous carcinoma (CC/MC), gemcitabine (GEM) had the strongest effect with a median TTF of 5.3 months, whilst nedaplatin (NDP) had the lowest effect with a median TTF of 1.4 months. In contrast, in the non-CC/MC group, irinotecan (CPT-11) and NDP had a better TTF than GEM and pegylated liposomal doxorubicin (PLD). There were notable differences in the treatment efficacy of NDP according to PFI. Specifically, NDP prolonged the TTF in patients with a PFI ≥ 3 months. Compared with GEM alone, GEM + Bev tended to prolong the TTF more effectively; however, an additive effect was not observed with PLD + Bev. Conclusions This study demonstrated that the effect of chemotherapy agents differed according to the tumor and background characteristics of the patient. Our findings will improve selection of effective therapies for patients with PR-OC by considering their background characteristics.

Recurrent cervical cancer with PD‐L1 amplification treated with nivolumab: A case enrolled in the BELIEVE trial

AbstractPatients with cervical cancer benefiting from immune checkpoint inhibitors (ICIs) are limited. Recently, PD‐L1 amplification has been attracted attention as a reliable marker of ICIs. A 47‐year‐old woman with stage IIB cervical cancer experienced disease progression during postoperative adjuvant chemotherapy. Cancer genomic profiling revealed that the tumor was microsatellite stable with PD‐L1 amplification, therefore, nivolumab was administered by enrolling in the BELIEVE trial. Despite nivolumab treatment, remarkable disease progression was observed. At the beginning of nivolumab treatment, the patient already had multiple liver metastases with severe systemic inflammation as indicated by a high neutrophil‐to‐lymphocyte ratio (NLR), both of which are negative predictive markers for ICI. Despite the presence of PD‐L1 amplification, nivolumab was ineffective in cancer progression, which may be attributable to the presence of liver metastasis and high NLR. ICI is recommended to be administered at an early stage of cancer treatment to enhance its effectiveness.

Identification of target cells of human papillomavirus 18 using squamocolumnar junction organoids

AbstractHuman papillomavirus 18 (HPV18) is a highly malignant HPV genotype among high‐risk HPVs, characterized by the difficulty of detecting it in precancerous lesions and its high prevalence in adenocarcinomas. The cellular targets and molecular mechanisms underlying its infection remain unclear. In this study, we aimed to identify the cells targeted by HPV18 and elucidate the molecular mechanisms underlying HPV18 replication. Initially, we established a lentiviral vector (HPV18LCR‐GFP vector) containing the HPV18 long control region promoter located upstream of EGFP. Subsequently, HPV18LCR‐GFP vectors were transduced into patient‐derived squamocolumnar junction organoids, and the presence of GFP‐positive cells was evaluated. Single‐cell RNA sequencing of GFP‐positive and GFP‐negative cells was conducted. Differentially expressed gene analysis revealed that 169 and 484 genes were significantly upregulated in GFP‐positive and GFP‐negative cells, respectively. Pathway analysis showed that pathways associated with cell cycle and viral carcinogenesis were upregulated in GFP‐positive cells, whereas keratinization and mitophagy/autophagy‐related pathways were upregulated in GFP‐negative cells. siRNA‐mediated luciferase reporter assay and HPV18 genome replication assay validated that, among the upregulated genes, ADNP, FHL2, and NPM3 were significantly associated with the activation of the HPV18 early promoter and maintenance of the HPV18 genome. Among them, NPM3 showed substantially higher expression in HPV‐related cervical adenocarcinomas than in squamous cell carcinomas, and NPM3 knockdown of HPV18‐infected cells downregulated stem cell‐related genes. Our new experimental model allows us to identify novel genes involved in HPV18 early promoter activities. These molecules might serve as therapeutic targets in HPV18‐infected cervical lesions.

Risk stratification of invasive cervical cancer diagnosed after cervical conization

Abstract Background Cervical intraepithelial neoplasia (CIN) diagnosis is based on colposcopy-aided histological examination. However, its accuracy in CIN diagnosis is limited. Some invasive cervical cancers (ICCs) are diagnosed after cervical conization. Therefore, risk stratification of undetected ICC is particularly important for the management of patients with CIN. This study aimed to identify the risk factors for undetected ICC. We especially focused on the association of human papillomavirus (HPV) genotypes. Methods We retrospectively reviewed the clinicopathological characteristics (including age, parity, and preoperative diagnosis) and HPV genotypes of 348 patients diagnosed with CIN or adenocarcinoma in situ (AIS) who underwent cervical conization at our hospital between 2008 and 2016. The relationship between preoperative factors, including HPV genotypes and post-conization ICC, was evaluated. Results Among the 348 patients, 322, 7, and 19 had preoperative CIN3, CIN2, and AIS, respectively; 181 were nulliparous. The median patient age was 41 (23–83) years. HPV genotyping was performed on 237 patients. Overall, post-conization ICC was detected in 16 patients (4.6%). Multivariate analysis showed that nulliparity and HPV16 positivity were the independent risk factors for post-conization ICC (OR: 6.01, P = 0.0302; OR: 5.26, P = 0.0347, respectively). The combination of HPV16 status and parity improved diagnostic accuracy. Seven of 53 HPV16-positive cases (13%) without childbirth history were diagnosed with post-conization ICC. In contrast, none of the HPV16-negative cases with childbirth history was diagnosed with post-conization ICC. Conclusion HPV16 positivity and nulliparity were identified as risk factors for undetected ICC. Careful treatment selection and preoperative scrupulous examination are especially important in these cases.

Heterogeneous treatment effects of adjuvant therapy for patients with cervical cancer in the intermediate‐risk group

AbstractBackgroundThe efficacy of adjuvant therapy for patients with cervical cancer with intermediate risk (CC‐IR) remains controversial. We examined the impact of adjuvant therapy on survival outcomes in patients with CC‐IR and evaluated the heterogeneous treatment effects (HTEs) of adjuvant therapies based on clinicopathologic characteristics.MethodsWe retrospectively analyzed a previous Japanese nationwide cohort of 6192 patients with stage IB–IIB cervical cancer who underwent radical hysterectomy. We created two pairs of propensity score‐matched treatment/control groups to investigate the treatment effects of adjuvant therapies: (1) adjuvant therapy versus non‐adjuvant therapy; (2) chemotherapy versus radiotherapy conditional on adjuvant therapy. Multivariate analyses with treatment interactions were performed to evaluate the HTEs.ResultsAmong the 1613 patients with CC‐IR, 619 and 994 were in the non‐treatment and treatment groups, respectively. Survival outcomes did not differ between the two groups: 3‐year progression‐free survival (PFS) rates were 88.1% and 90.3% in the non‐treatment and treatment groups, respectively (p = 0.199). Of the patients in the treatment group, 654 and 340 received radiotherapy and chemotherapy, respectively. Patients who received chemotherapy had better PFS than those who received radiotherapy (3‐year PFS, 90.9% vs. 82.9%, p = 0.010). Tumor size was a significant factor that affected the treatment effects of chemotherapy; patients with large tumors gained better therapeutic effects from chemotherapy than those with small tumors.ConclusionAdjuvant therapy is optional for some patients with CC‐IR; however, chemotherapy can be recommended as adjuvant therapy, particularly for patients with large tumors.

Downregulation of HLA Class I Expression through HLA-A DNA Methylation Is Associated with Reduced CD8+ T-cell Infiltration in Cervical Cancer

Abstract Human leukocyte antigen class I (HLA-I) is central to tumor immune recognition, but its regulatory mechanisms in cervical cancer remain poorly understood. This study aimed to elucidate the impact of HLA-I regulatory mechanisms on CD8+ T-cell infiltration and identify distinct histotype-specific immune escape strategies across cervical cancer subtypes. Using 98 cervical cancer cases, including squamous cell carcinoma (SCC; n = 53), adenocarcinoma (n = 32), gastric-type adenocarcinoma (GAS; n = 5), small cell carcinoma (Small, n = 4), and mixed histologic types (n = 4), we examined the relationship between CD8+ T-cell infiltration patterns (categorized as infiltrated, excluded, or absent) and HLA-I expression, HLA-A DNA methylation, and HLA-I loss of heterozygosity (LOH). CD8+ T-cell infiltration patterns varied significantly by histologic subtype (P < 0.0001). SCC showed the highest frequency of the infiltrated pattern (73.6%), whereas GAS and Small predominantly displayed an absent pattern. Reduced CD8+ T-cell infiltration correlated with poor survival (P < 0.0001). HLA-I expression mirrored these trends being highest in SCC and lowest in Small and GAS. HLA-A DNA methylation emerged as a key driver of HLA-I downregulation, leading to reduced CD8+ infiltration (P < 0.05). In SCC, both HLA-A methylation and HLA-I LOH contributed to immune evasion; cases lacking these alterations exhibited the highest CD8+ T-cell infiltration levels (P < 0.01). This study identifies distinct HLA-I regulatory mechanisms in cervical cancer, highlighting HLA-A methylation—and particularly HLA-I LOH in SCC—as key drivers of immune evasion. These findings provide a foundation for developing predictive biomarkers and suggest that targeting these specific HLA-I regulatory mechanisms could enhance immunotherapy efficacy.

The automatic diagnosis artificial intelligence system for preoperative magnetic resonance imaging of uterine sarcoma

Magnetic resonance imaging (MRI) is efficient for the diagnosis of preoperative uterine sarcoma; however, misdiagnoses may occur. In this study, we developed a new artificial intelligence (AI) system to overcome the limitations of requiring specialists to manually process datasets and a large amount of computer resources. The AI system comprises a tumor image filter, which extracts MRI slices containing tumors, and sarcoma evaluator, which diagnoses uterine sarcomas. We used 15 types of MRI patient sequences to train deep neural network (DNN) models used by tumor filter and sarcoma evaluator with 8 cross-validation sets. We implemented tumor filter and sarcoma evaluator using ensemble prediction technique with 9 DNN models. Ten tumor filters and sarcoma evaluator sets were developed to evaluate fluctuation accuracy. Finally, AutoDiag-AI was used to evaluate the new validation dataset, including 8 cases of sarcomas and 24 leiomyomas. Tumor image filter and sarcoma evaluator accuracies were 92.68% and 90.50%, respectively. AutoDiag-AI with the original dataset accuracy was 89.32%, with 90.47% sensitivity and 88.95% specificity, whereas AutoDiag-AI with the new validation dataset accuracy was 92.44%, with 92.25% sensitivity and 92.50% specificity. Our newly established AI system automatically extracts tumor sites from MRI images and diagnoses them as uterine sarcomas without human intervention. Its accuracy is comparable to that of a radiologist. With further validation, the system could be applied for diagnosis of other diseases. Further improvement of the system's accuracy may enable its clinical application in the future.