title: Association between polymorphisms in the promoter region of T cell immunoglobulin and mucin domain-3 and myasthenia gravis-associated thymoma.
abstract: Thymoma is a type of benign or low-grade malignant tumor, occurring on the thymic epithelium. Patients with thymoma may also suffer from myasthenia gravis (MG), presenting MG-associated thymoma. T cell immunoglobulin and mucin domain-3 (Tim-3), a subtype of the Tim protein family, may be an important immune regulatory and pivotal molecule associated with tumor development. In order to understand the etiology and pathogenesis of MG-associated thymoma in the Han population of North China, the present study investigated the association between a polymorphism on the -574 locus in the promoter of Tim-3 and the risk of MG-associated thymoma in the Han Chinese population. In total, 116 patients with thymoma and MG were enrolled into the MG-associated thymoma group, while 124 patients with thymoma, but without MG, were enrolled into the non-MG-associated thymoma group. Examinations were conducted to reach a definite diagnosis of thymoma and MG and rule out other autoimmune diseases. Allele-specific polymerase chain reaction (AS-PCR) was performed to determine the polymorphism on the -574 locus of Tim-3 in all the subjects. PCR products were randomly selected for sequencing. Statistically significant differences were detected between the distribution frequencies of the GT+TT genotype and T allele on the -574 locus of the MG-associated thymoma group (31.03 vs. 12.90%, respectively; χ2=11.609, P=0.001) and the non-MG-associated thymoma group (15.52 vs. 6.45%, respectively; χ2=10.198, P=0.001). In conclusion, the present study indicated that an association may exist between the polymorphism of the -574 locus in the Tim-3 promoter and MG-associated thymoma.
authors: Department of Emergency, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China.
authors: Guowu
authors: G
authors: Xu
authors: Department of Cardiothoracic Surgery, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China.
authors: Kai
authors: K
authors: Zheng
authors: Department of Intensive Care Unit, Tianjin Third Central Hospital, Tianjin 300170, P.R. China.
authors: Xing
authors: X
authors: Lu
authors: Department of Emergency, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China.
authors: Jinxiang
authors: J
authors: Wang
authors: Department of Emergency, Tianjin Medical University General Hospital, Tianjin 300052, P.R. China.
authors: Yanfen
authors: Y
authors: Chai
authors: Department of Intensive Care Unit, Tianjin Third Central Hospital, Tianjin 300170, P.R. China.
authors: Junyi
authors: J
authors: Wang
keywords: T-cell immunoglobulin and mucin domain-3; gene polymorphism; myasthenia gravis; thymoma