Investigator

Min Chul Choi

University Of Ulsan

MCCMin Chul Choi
Papers(10)
Identification of Pro…Establishment and Its…Practice guidelines f…Clinical practice gui…Real-World Experience…Major clinical resear…A single-arm, phase I…Comparisons of surviv…Discrepancy between C…Comparative performan…
Collaborators(10)
Maria LeeDong Hoon SuhSeung-Hyuk ShimSo Jin ShinHaeyoun KangHeon Jong YooWon Duk JooWoo Yeon HwangYong Beom KimJae Yun Song
Institutions(9)
University Of UlsanSeoul National Univer…Seoul National Univer…Konkuk University Hos…Keimyung University S…CHA UniversityChungnam National Uni…Kyung Hee University …Korea University Anam…

Papers

Identification of Prognostic Biomarkers of Ovarian High-Grade Serous Carcinoma: A Preliminary Study Using Spatial Transcriptome Analysis and Multispectral Imaging

Ovarian cancer is a lethal malignancy, with most patients initially responding to chemotherapy but frequently experiencing recurrence. Previous studies primarily examined tumor characteristics using limited genetic markers or bulk RNA sequencing. Here, we used spatial transcriptomics via the GeoMx® platform, alongside multispectral immune cell immunofluorescence (IF), to identify biomarkers associated with disease progression following first-line treatment of high-grade serous carcinoma (HGSC). We identified several spatial biomarkers linked to non-recurrence, including elevated NKG7 expression in CD45+ immune cell regions (p = 0.0011) and higher TFPI2 and PIGR expression in tumor areas (p = 2.09 × 10−6), both associated with improved progression-free survival. Multispectral IF revealed significantly higher regulatory T cell (Treg) to CD8+ T cell ratios in the tumor nests and stroma of recurrent patients (p = 0.016, 0.048). Tregs were also found closer to cancer cells or macrophages than CD8+ T cells in recurrent tumors (p = 0.048), correlating with poor survival. Integrated analysis showed that immune cell density and immune pathway scores in the recurrent group positively correlated with cancer pathway scores, except for NF-κB. This comprehensive analysis revealed clues to interactions between different immune cells and identified biomarkers that may be useful for predicting recurrence of HGSC.

Establishment and Its Utility of a Patient-Derived Cell Xenografts (PDCX) Model with Cryopreserved Cancer Cells from Human Tumor

Patient-derived xenograft (PDX) models are powerful tools in cancer research, offering an accurate platform for evaluating cancer treatment efficacy and predicting responsiveness. However, these models necessitate surgical techniques for tumor tissue transplantation and face challenges with non-uniform tumor growth among animals. To address these issues, we attempted to develop a new PDX modeling method using high-grade serous ovarian cancer (HGSC), a fatal disease with a 5-year survival rate of 29%, which requires personalized research due to its morphological, genetic, and molecular heterogeneities. In this study, we developed a new patient-derived cancer cell xenograft (PDCX) model with high engraftment efficiency (64%) that utilizes primary cancer cells instead of patient tissues. Primary cancer cells can be stably cryopreserved for extended periods (up to 485 days), and when transplanted into female NSGA mice, they maintain morphological and molecular characteristics without significant genetic differences compared to their original primary tumors. Furthermore, PDCX models can be easily produced using a syringe, allowing for uniform tumor sizes across multiple animals. Additionally, M2 PDCXs exhibited a significantly faster growth rate compared to M2 PDTXs. Consequently, our PDCX model offers a streamlined approach for evaluating personalized cancer treatments with minimal experimental variability.

Real-World Experience with Pembrolizumab Treatment in Patients with Heavily Treated Recurrent Gynecologic Malignancies

We evaluated the efficacy and safety of pembrolizumab in patients with recurrent gynecologic cancers in real-world practice. We conducted a retrospective, single-institution study of patients with recurrent gynecologic malignancies treated with pembrolizumab. The primary endpoints were the objective response rate (ORR) and safety. Thirty-one patients treated with pembrolizumab were included. The primary disease sites were the uterine cervix (n=18), ovaries (n=8), and uterine corpus (n=5). Fifteen of the 31 patients (48%) had an Eastern Cooperative Oncology Group performance status of ≥2. The median number of prior chemotherapy lines was 2 (range, 1-6), and 14 of 31 patients (45%) had received ≥ 3 prior lines of chemotherapy. The overall ORR was 22.6%: specifically, 22.3% (4 of 18 patients), 12.5% (1 of 8 patients), and 40% (2 of 5 patients) for cervical, ovarian, and endometrial cancers, respectively. During a median follow-up of 4.7 months (range, 0.2-35.3), the median time to response was 1.9 months (range, 1.4-5.7). The median duration of response was not reached (range, 8.8-not reached). The median progression-free survival was 2.5 months (95% confidence interval, 1.7-not reached). Adverse events occurred in 20 patients (64.5%), and only 3 (9.7%) were grade ≥3. There was one case of suspicious treatment-related mortality, apart from which most adverse events were manageable. In real-world practice, pembrolizumab was feasible and effective in heavily treated recurrent gynecologic cancer patients with poor performance status who may not be eligible for enrollment in clinical trials.

A single-arm, phase II study of niraparib and bevacizumab maintenance therapy in platinum-sensitive, recurrent ovarian cancer patients previously treated with a PARP inhibitor: Korean Gynecologic Oncology Group (KGOG 3056)/NIRVANA-R trial

Given the expanding clinical use of poly(adenosine diphosphate [ADP]-ribose) polymerase inhibitors (PARPis), there is a significant need for optimal strategies with which to treat patients whose cancer progresses while using a PARPi. However, the treatment consensus after PARPi has not been established. The aim of the Korean Gynecologic Oncology Group (KGOG) 3056/NIRVANA-R trial is to investigate the efficacy of niraparib in combination with bevacizumab as a maintenance therapy in platinum-sensitive ovarian cancer patients who were previously treated with a PARPi. The KGOG 3056/NIRVANA-R is a multi-centre, investigator-initiated, single-arm, phase II trial of patients with platinum-sensitive recurrent ovarian cancer recruited from seven KGOG sites. This study included patients with platinum-sensitive recurrent epithelial ovarian cancer who received at least 2 previous courses of platinum-containing therapy and had been treated with a PARPi. Mucinous histology type was excluded. Patients who had responded to the last platinum regimen (either complete or partial response) were eligible to participate in this study. Forty-four patients will be recruited. All enrolled patients are treated with niraparib and bevacizumab for maintenance therapy until disease progression, unacceptable toxicity, or withdrawal of patient consent. The primary endpoint of the study is 6-month progression-free survival rate. Accrual is expected to be completed in 2022, followed by presentation of results in 2023. ClinicalTrials.gov Identifier: NCT04734665.

Discrepancy between Cytology and Histology in Cervical Cancer Screening: a Multicenter Retrospective Study (KGOG 1040)

Cervical cancer is the fourth common cancer in women worldwide. The Papanicolau test is the primary screening procedure to detect abnormal cervical cells. Colposcopy is the main procedure for discriminating high-grade cervical lesions. The study aimed at clarifying the discrepancy between cervical cytology and colposcopic biopsy histology as well as confounding factors. Eligible patients visited thirteen tertiary hospitals for colposcopic biopsy following cervical cytology and human papillomavirus (HPV) genotypes between January and December 2018. Baseline characteristics including age, body mass index (BMI), and parity were collected. In our study, 3,798 eligible patients were included. Mean age of patients was 42.7 (19-88) years and mean BMI was 22.5 (16.9-34.1) kg/m². The referred cervical cytologic findings consisted of 495 normal, 1,390 atypical squamous cells of undetermined significance, 380 atypical squamous cells cannot exclude high-grade squamous intraepithelial lesion, 792 low-grade squamous intraepithelial lesion, 593 high-grade squamous intraepithelial lesion, 79 atypical glandular cells, 46 squamous cell carcinoma, and 23 adenocarcinoma. HPV-positive findings were found in 3,008 (79.2%) patients and were not detected in 914 (24.1%) cases. The risk of unexpected low-grade lesions from histology was higher in patients > 45 years (odds ratio [OR], 2.137; 95% confidence intervals [CIs], 1.475-3.096). In contrast, the risk of unexpected high-grade lesions from colposcopic biopsy was lower in patients ≥ 45 years (OR, 0.530; 95% CI, 0.367-0.747) and HPV 16/18 infection was higher than other HPV (OR, 1.848; 95% CI, 1.385-2.469). Age and HPV genotypes were responsible for the discrepancies between cytology and histology. Precautions should be taken for women over the age of 45 in triage for colposcopy in order to avoid unnecessary testing.

Comparative performance of various human papillomavirus assays available in Korea for detecting cervical intraepithelial neoplasia

AbstractAimThe aim of this study was to evaluate the clinical performance for detecting cervical intraepithelial neoplasia (CIN) 2 or higher lesions among available human papillomavirus infection (HPV) genotyping tests in Korea.MethodsEligible patients visited 13 tertiary hospitals for colposcopic biopsy following cervical cytology and HPV genotyping test between January and December 2018. Baseline characteristics including age, body mass index (BMI), and parity were collected from 3798 patients. The performance of the Roche Cobas HPV 4800 was evaluated against other domestic HPV assays to detect CIN2 or higher.ResultsA total of seven types of HPV genotyping tests were analyzed in the research institutes. A total of 1358 patients (35.8%) tested Anyplex II HPV 28 and 701 patients (18.5%) tested Cobas 4800 HPV. The overall sensitivity in the detection of CIN2 or higher was 41.5% (38.9–44.1) in patients positive for HPV 16/18.The Cobas test for HPV 16/18 was concordant with other assays evaluated for detection of CIN2 or higher and showed sensitivity of 46.6%, which was not significantly different from other assays. Although Anyplex II HPV28 (Seegene) showed slightly decreased sensitivity for detecting CIN2 or higher lesion with HPV 16/18 positive (39.8%, p < 0.05) compared to Cobas 4800, in aspect of high‐risk HPV positive, Anyplex II HPV28 showed increased sensitivity (96.9%, p < 0.05).ConclusionThe performance of the HPV genotype test that were commonly used in Korea was concordant with Cobas HPV test. Further studies are needed to evaluate the safety, efficiency, and cost‐effectiveness of the various commercially available domestic HPV assays.

11Works
10Papers
51Collaborators
1Trials
Neoplasm Recurrence, LocalOvarian NeoplasmsEndometrial NeoplasmsGenital Neoplasms, FemaleUterine Cervical NeoplasmsUterine NeoplasmsNeoplasm StagingNeoplasms