Postoperative adjuvant dose-dense chemotherapy with bevacizumab and maintenance bevacizumab after neoadjuvant chemotherapy for advanced ovarian cancer: A phase II AGOG/TGOG trial

Mutations in circulating tumor DNA detected in the postoperative period predict poor survival in patients with ovarian cancer

BACKGROUND

We investigated whether mutations in plasma circulating tumor DNA (ctDNA) can provide prognostic insight in patients with different histological types of ovarian carcinoma. We also examined the concordance of mutations detected in ctDNA samples with those identified in the corresponding formalin-fixed paraffin-embedded (FFPE) tumor specimens.

METHODS

Between July 2016 and December 2017, 29 patients with ovarian carcinoma were prospectively enrolled. FFPE tumor specimens were obtained from all participants. A total of 187 blood samples for ctDNA analysis were collected before surgery (C0), immediate after surgery before adjuvant chemotherapy (C1), and at six-month intervals. Progression-free survival (PFS) and overall survival (OS) served as the main outcome measures.

RESULTS

The study cohort consisted of 13 (44.8%) patients with high-grade serous carcinomas (HGSC), 9 (31.0%) with clear cell carcinoma, 2 (6.9%) with mucinous carcinomas, 4 (13.8%) with low-grade serous carcinomas, and 1 (3.4%) with endometrioid carcinoma. Twenty-four (82.8%) patients had at least one detectable ctDNA variant. The concordance rate between mutations identified in pretreatment ctDNA and corresponding FFPE tumor specimens was 92.3% for patients with HGSC and 58.6% for the entire cohort. The median follow-up time was 33.15 months (range: 0.79-46.13 months). Patients with an advanced stage disease more likely had detectable ctDNA mutations before surgery (C0) and after surgery at C1, while those with HGSC more likely had ctDNA mutations detected before surgery. The presence of ctDNA mutations at C1 was an independent predictor of worse OS with a hazard ratio of 6.56 (95% confidence interval, (1.07-40.17) for detectable versus undetectable C1 ctDNA variants, p = 0.042).

CONCLUSIONS

ctDNA mutations are common in patients with ovarian carcinoma. The presence of ctDNA mutations after surgery was an independent predictor of less favorable PFS and OS.

Colorectal cancer tumor stem cells mediate bevacizumab resistance through the signal IL-22-STAT3 signaling pathway

Bevacizumab is the standard treatment for colorectal cancer (CRC) in the advanced stage. However, poor diagnosis identified due to the bevacizumab resistance in many CRC patients. Previous studies have found that CRC stem cells (CCSCs) and interleukin 22 (IL-22) are involved in the resistance of bevacizumab, however, the mechanism of remains unclear. In this study, we established the bevacizumab drug-resistant cell line HCT-116-R by concentration gradient method, and the cell viability was detected by CCK-8 assay. The resistance of bevacizumab in CRC cell lines HCT-116-R was identified by characterizing epithelial-mesenchymal transition (EMT). Additionally, HCT-116-R cell lines were isolated from CCSCs and their tumorigenicity was validated in nude mice. We observed that that compared with the matched group, the expression of IL-22, IL-22R, STAT3, and GP130 in drug-resistant cells increased distinctly, with blocked IL-22 cells were successfully constructed by lentiviral interference. The level of proteins in stem cell landmarks (EpCAM, CD133), and stem cell landmarks (Oct4, Sox2) was identified by western blotting. Furthermore, the IL-22 role was evaluated by xenograft model. We found that short hairpin RNA (shRNA) suppression of IL-22 expression can restore the sensitivity of drug-resistant CCSCs to bevacizumab, Moreover, xenograft tumor models show that suppression of IL-22 can increase the anti-tumor influence of bevacizumab. In summary, we demonstrated that CCSCs play a major part in bevacizumab-resistant CRC. Inhibiting the signaling pathway of IL-22/STAT3 can improve the anti-tumor influence on bevacizumab in vitro and in vivo. Thus, IL-22 may represent a new anti-bevacizumab target in CRC.

East Asian Gynecologic Oncology Trial Group (EAGOT): founding history and future perspective

Racial and regional differences exist in morbidity, histology, drug response, toxicity, and prognosis of gynecologic cancer. However, most large-scale phase III studies have been conducted in Western countries, and these data on Asians, who account for more than half of the world's population, are limited. To build a global clinical trial network in Asia, four clinical trial groups with high expertise and international competitiveness in East Asia, namely the Japanese Gynecologic Oncology Group in Japan, the Korean Gynecologic Oncology Group in Korea, the Taiwanese Gynecologic Oncology Group in Taiwan, and the Chinese Gynecologic Cancer Society in the People's Republic of China, established a new group called the East Asia Gynecologic Oncology Trial Group (EAGOT) on November 19, 2021. It includes four committees: the Cervical Cancer Committee, Uterine Corpus Cancer Committee, Ovarian Cancer Committee, and Translational Research Committee. The purpose of EAGOT is to conduct international clinical trials in an effort to provide the best treatments for Asian women affected by gynecologic cancer. Discussions on new collaborative clinical trials have already begun. The first Annual EAGOT Meeting was held on May 25-27, 2023 in Niigata, Japan. EAGOT, the largest healthcare/investigational innovation network in Asia in the area of gynecologic cancers, will become a platform for establishing standards of care and lead to guidelines for Asian women suffering from gynecologic cancer. The harmonization of regulatory/investigator-initiated clinical trials, simultaneous approval of unapproved drugs in the four countries under a common protocol, and expansion of indications will improve the prognosis of gynecologic cancers in Asia in the near future.