Deficient mismatch repair and RAS mutation in colorectal carcinoma patients: a retrospective study in Eastern China

作者：Zhang, Xiangyan; Ran, Wenwen; Wu, Jie; Li, Hong; Liu, Huamin; Wang, Lili; Xiao, Yujing; Wang, Xiaonan; Li, Yujun; Xing, Xiaoming^*

来源：PeerJ, 2018, 6: e4341.

DOI：10.7717/peerj.4341

• KRAS mutation
• Deficient mismatch repair (dMMR)
• NRAS mutation
• Prognosis
• Clinicopathological characteristics
• Colorectal carcinoma

Objectives. To investigate the frequency and prognostic role of deficient mismatch repair (dMMR) and RAS mlitatiOn in Chinese patients with colorectal carcinoma. @@@ Methods. Clinical' and pathological information from 813 patients were reviewed and Expression of mismatch repair proteins was tested by immunohistochemistry. Mutation analyses for RAS gene were performed by real-time polymerase chain reaction. Correlations of mismatch repair status and RAS mutation status with clinicopathological characteristics and disease survival were determined. @@@ Results. The overall percentage of dMMR was 15.18% (121/797). The proportion of dMMR was higher in patients <50 years old (p < 0.001) and in the right side of the colon < 0.001). Deficient mismatch repair was also associated with mucinous production (p < 0.001), poor differentiation (p < 0.001), early tumor stage (p < 0.05) and bowel wall invasion (p <,0.05). The overall RAS mutation rate was 45.88%, including 42.56% (346/813) BRAS mutation and 3.69%) (30/813) NRAS mutation (including three patients with mutations in both). RRAS mutation was significantly associated with mucinous production (p < 0.05), tumor stage (p < 0.05) and was higher in nonsmokers (p < 0.05) and patients with a family history of colorectal carcinoma (p < 0.05). Overall, 44.63% (54/121) dMMR tumors harbored KRAS mutation, however, dMMR tumors were less likely to have NRAS mutation. Moreover, dMMR, KRAS and NRAS mutation were not prognostic factors for stager I-III colorectal carcinoma. @@@ Conclusions. This study confirms that the status of molecular markers involving mismatch repair status and RAS mutation reflects the specific clinicopathological characteristics of colorectal carcinoma.

• 出版日期2018-2-5
• 单位青岛大学