TY - JOUR AB - Microsatellite instability (MSI) detection is widely used in the diagnosis and prognosis evaluation of colorectal cancer. However, for gastric cancer (GC), there is no standard panel of microsatellites (MSs) used in clinical guidance. The present study aimed to identify useful predictors of the clinical features and for the prognosis of GC, based on an investigation of MSI and loss of heterozygosity (LOH) in tumor‑related genes. First, from 20 tumor‑related genes which were proven to be important to the development of GC, 91 MSs were identified, and PCR amplification, short tandem repeat scanning analysis and TA clone sequencing were used to analyze MSI and LOH in the first set of 90 GC samples. Subsequently, the same method was used to detect the MSI/LOH of the optimized loci in the second set of 136 GC samples. MSI/LOH in the mismatch repair genes was highly consistent with that in oncogenes and tumor suppressor genes, respectively. The length of the core sequence was a main factor for the MSI/LOH rate. The MSI of 12 single loci was significantly associated with lymph node metastasis. The MSI in TP53‑1 and the LOH in MGMT‑10 were significantly associated with early stages of tumor infiltration depth. The LOH in MGMT‑10, PTN‑2 and MCC‑17 was significantly associated with TNM stage. The LOH in TP53‑1 and ERBB2‑12 was associated with adenocarcinoma. The MSI/LOH in 6 single loci of 5 tumor‑related genes was associated with poor prognosis of GC. The present study demonstrated that the MSI/LOH of loci in tumor‑associated genes was associated with 4 clinicopathological characteristics and outcomes of GC. These results may provide potential specific biomarkers for the clinical prediction and treatment of GC. AD - School of Basic Medical Sciences, Capital Medical University, Beijing 100069, P.R. China Tumor Model Laboratory, Beijing Key Laboratory of Cancer Invasion and Metastasis Research, Beijing 100069, P.R. China AU - Huo,Xueyun AU - Xiao,Xiaoqin AU - Zhang,Shuangyue AU - Du,Xiaoyan AU - Li,Changlong AU - Bai,Zhigang AU - Chen,Zhenwen DA - 2021/06/01 DO - 10.3892/ol.2021.12691 IS - 6 JO - Oncol Lett KW - microsatellite stability loss of heterozygosity gastric cancer prognosis tumor‑related genes PY - 2021 SN - 1792-1074 1792-1082 SP - 430 ST - Characterization and clinical evaluation of microsatellite instability and loss of heterozygosity in tumor‑related genes in gastric cancer T2 - Oncology Letters TI - Characterization and clinical evaluation of microsatellite instability and loss of heterozygosity in tumor‑related genes in gastric cancer UR - https://doi.org/10.3892/ol.2021.12691 VL - 21 ER -