Associations and prognostic implications of Eastern Cooperative Oncology Group performance status and tumoral LINE-1 methylation status in stage III colon cancer patients

作者：Chen, Duo; Wen, Xianyu; Song, Young Seok; Rhee, Ye-Young; Lee, Tae Hun; Cho, Nam Yun; Han, Sae-Won; Kim, Tae-You; Kang, Gyeong Hoon^*

来源：Clinical Epigenetics, 2016, 8(1): 36.

DOI：10.1186/s13148-016-0203-8

• Adjuvant therapy
• Colorectal cancer
• ECOG
• FOLFOX
• LINE-1
• Methylation
• Prognosis

Background: Low methylation status of LINE-1 in tumors is associated with poor survival in patients with colon cancer. Eastern Cooperative Oncology Group performance status (ECOG-PS) is a method to assess the functional status of a patient. We retrospectively evaluated the relationship between ECOG-PS and LINE-1 methylation in colorectal cancers (CRCs) and their prognostic impact in CRC or colon cancer patients receiving adjuvant 5-fluorouracil/leucovorin/oxaliplatin (FOLFOX).
Results: LINE-1 methylation and microsatellite instability were analyzed in stage III or high-risk stage II CRCs (n = 336). LINE-1 methylation levels were correlated with clinicopathological features, including PS and recurrence-free survival (RFS). The association between the tumoral LINE-1 methylation level and PS was observed (OR = 2.56, P < 0.001). Differences in LINE-1 methylation levels in cancer tissue between the PS 0 and 1 groups were significant in patients older than 60 years (P = 0.001), the overweight body mass index group (P = 0.005), and the stage III disease group (P = 0.008). Prognostic significances of LINE-1 methylation status or combined PS and LINE-1 methylation statuses were identified in stage III colon cancers, not in stage III and high-risk stage II CRCs. Low LINE-1 methylation status was closely associated with a shorter RFS time. The difference between PS(0)/LINE-1(high) and PS(>= 1)/LINE-1(low) was significant, which suggests that colon cancer patients with concurrent PS(>= 1)/LINE-1 (low) have a higher recurrence rate.
Conclusions: PS was associated with LINE-1 methylation in CRC tissue. LINE-1 methylation was associated with RFS in stage III colon cancer patients who were treated with adjuvant FOLFOX chemotherapy. Combined PS and LINE-1 methylation status might serve as a useful predictor of cancer recurrence.

• 出版日期2016-4-5
• 单位北京大学