1. Prediction of Efficacy of Postoperative Chemotherapy by DNA Methylation of CDO1 in Gastric Cancer
- Author
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Takafumi Soeno, Nobuyuki Nishizawa, Hiroki Harada, Keishi Yamashita, Hideki Ushiku, Keigo Yokoi, Naoki Hiki, and Kei Hosoda
- Subjects
Male ,Tumor suppressor gene ,Colorectal cancer ,medicine.medical_treatment ,Antineoplastic Agents ,Kaplan-Meier Estimate ,Epigenesis, Genetic ,03 medical and health sciences ,0302 clinical medicine ,Gastrectomy ,Risk Factors ,Stomach Neoplasms ,Cell Line, Tumor ,Biomarkers, Tumor ,medicine ,Humans ,Promoter Regions, Genetic ,Lymph node ,Aged ,Neoplasm Staging ,Retrospective Studies ,Tegafur ,Aged, 80 and over ,Chemotherapy ,business.industry ,Stomach ,Age Factors ,Cysteine Dioxygenase ,Cancer ,Methylation ,DNA Methylation ,Prognosis ,medicine.disease ,Drug Combinations ,Oxonic Acid ,medicine.anatomical_structure ,Chemotherapy, Adjuvant ,Drug Resistance, Neoplasm ,030220 oncology & carcinogenesis ,DNA methylation ,Cancer cell ,Cancer research ,Female ,030211 gastroenterology & hepatology ,Surgery ,Neoplasm Recurrence, Local ,business ,Follow-Up Studies - Abstract
Background CDO1 is a presumed tumor suppressor gene in human cancers, the expression of which is silenced by promoter DNA methylation. Moreover, CDO1 harbors functionally oncogenic aspects through modification of mitochondrial membrane potential. We recently proposed that this oncogenic feature allows for the prediction of the efficacy of postoperative chemotherapy in colon cancer. The present study aims to elucidate the efficacy of prediction of success of postoperative chemotherapy in advanced gastric cancer to improve the treatment strategy of patients. Materials and methods Forced expression of CDO1 in gastric cancer cell lines was assessed using the JC-1 assay. Promoter DNA methylation was investigated in quantitative TaqMan methylation–specific polymerase chain reaction in 321 pathological stage II/III advanced gastric cancer cases treated by curative gastrectomy with or without postoperative chemotherapy. Results (1) Forced expression of CDO1 led to increased mitochondrial membrane potential, accompanied by augmented survival in gastric cancer cells under anaerobic conditions. These results suggest that CDO1-expressing cancer cells survive more easily in anaerobic lesions which are inaccessible to anticancer drugs. (2) Intriguingly, in cases with the highest CDO1 methylation (ranging from 15% to 40%), patients with postoperative chemotherapy showed significantly better survival than those with no postoperative chemotherapy. (3) A robust prognostic difference was observed that was explained by differential recurrences of distant metastasis (P = 0.0031), followed by lymph node (P = 0.0142) and peritoneal dissemination (P = 0.0472). Conclusions The oncogenic aspects of CDO1 can be of use to determine patients with gastric cancer who will likely respond to treatment of invisible systemic dissemination by postoperative adjuvant chemotherapy.
- Published
- 2020