Objective: To detect the high mobility group A2 (HMGA2) expression in renal carcinoma, and to explore the relationship with clinicopathological features and its significance for prognosis. Methods: 50 renal carcinoma specimens, 50 corresponding adjacent normal kidney tissue samples, and 40 benign renal tumor specimens were used in this study. The expressions of HMGA2 mRNA and protein were detected by RT-PCR, Western blot and immunohistochemical assays, and its relationship with clinicopathological features and prognosis in the renal carcinoma patients was analyzed. Results: The RT-PCR results showed that the relative expression levels of HMGA2 mRNA in the renal carcinoma, benign renal tumor tissues, and adjacent normal renal tissues were 0.84±0.23, 0.19± 0.06 and 0.08±0.04, respectively, and the expression in renal carcinoma tissue was significantly higher than those of the other 2 groups (P<0.01). The Western blot results showed that the relative expression levels of HMGA2 protein in the renal carcinoma, benign renal tumor tissues, and adjacent normal renal tissues were 0.91±0.24, 0.12±0.04 and 0.03±0.01, respectively, and the expression in renal carcinoma tissue was significantly higher than those of the other 2 groups (P<0.01). Immunohistochemical results showed that the expression of HMGA2 protein exhibited brown and tan granular, which mainly distributed in the cell nuclei. Among the 50 cases of renal carcinoma, 34 cases exhibited positive expression, with a positive rate of 68.0%. Among the 40 cases of benign tumor tissues, 3 cases had positive expression, with a positive rate of 7.5%, while among the 50 cases of adjacent normal renal tissues, there was only 1 case exhibiting positive expression of HMGA2 protein, with a positive rate of 2.0%. The protein expression of HMGA2 was significantly higher in the renal carcinoma than in the benign tumors and normal renal tissues (P=0.004). There was no statistically significant difference in the association of HMGA2 protein expressions with age, sex, tumor size and histological type (P>0.05), while significant difference did exist in the association with different statuses of TNM staging and lymph node metastasis (P<0.05). The median time to progression (TTP) in 34 HMGA2 protein-positive patients was (22.36±1.48) months and that of 16 HMGA2 protein-negative patients was (34.55±1.87) months (P<0.05). Conclusions: HMGA2 plays an important role in the tumorigenesis and development of renal carcinoma, and may be used as an important predictor for estimating the prognosis of renal carcinoma. HMGA2 might become a new diagnostic and prognostic marker for renal carcinoma.
目的： 探讨高迁移率族蛋白A2(HMGA2)在肾癌组织中的表达情况及其与临床病理特征和预后的关系。 方法： 选取肾癌组织及癌旁组织50例、肾脏良性肿瘤组织40例，采用免疫组化法检测HMGA2蛋白的表达情况，采用逆转录聚合酶链反应(RT－PCR)和Western blot法检测肾癌组织、癌旁组织及肾脏良性肿瘤组织中HMGA2 mRNA和蛋白表达水平，分析HMGA2表达与肾癌患者临床病理特征及预后的关系。 结果： RT－PCR检测显示，HMGA2 mRNA在肾癌组织及癌旁组织、肾良性肿瘤组织中的表达水平分别为0.84±0.23、0.08±0.04和0.19±0.06 ，肾癌组织中的HMGA2 mRNA表达水平明显高于癌旁组织和肾良性肿瘤组织(P<0.01)。Western blot检测显示，肾癌组织、癌旁组织和肾良性肿瘤组织中HMGA2蛋白表达水平分别为0.91±0.24、0.03±0.01和0.12±0.04，肾癌组织中HMGA2蛋白水平明显高于癌旁组织和肾良性肿瘤组织，差异有统计学意义(P<0.01)。免疫组化检测显示，HMGA2蛋白阳性表达均呈棕黄色、棕褐色细颗粒状，主要分布于细胞核。50例肾癌组织中，HMGA2蛋白阳性表达34例，阳性率为68.0%。50例癌旁组织中，HMGA2蛋白阳性表达1例，阳性率为2.0%。40例肾良性肿瘤组织中，HMGA2蛋白阳性表达3例，阳性率为7.5%。肾癌组织中HMGA2蛋白的阳性率明显高于癌旁组织和肾良性肿瘤组织(P＝0.004)。HMGA2蛋白表达与肾癌患者的TNM分期和淋巴结转移状态有关(均P<0.05)，而与患者年龄、性别、肿瘤大小、肿瘤病理类型无关(均P>0.05)。34例HMGA2蛋白阳性表达肾癌患者的中位疾病进展时间(TTP)为(22.36±1.48)个月，而16例HMGA2蛋白阴性表达肾癌患者的中位TTP为(34.55±1.87)个月，差异有统计学意义(P<0.05)。 结论： HMGA2有可能成为肾癌诊断和预后的指标，在肾癌的发生发展中有一定作用。.
Keywords: Clinicopathological features; Diagnosis; High mobility group A2; Immunohistochemistry; Prognosis; Renal neoplasms.