Low levels of STAT5a protein in breast cancer are associated with unfavorable clinical outcomes
LIU Wei1, LONG Mei-jun2, WU Jue-kun2, LI Xi2, QIU Wan-shou2
1Department of Breast, Guangzhou Red Cross Hospital, Guangzhou 510220, China; 2Department of Thyroid and Breast Surgery, The Third Affiliated Hospital of Sun Yat-sen University, Guangzhou 510630, China.
目的:检测信号转导和转录活化蛋白5a（signal transducer and activator of transcription 5a，STAT5a）在浸润性乳腺癌组织中的表达情况，探索STAT5a在乳腺癌患者中潜在的临床意义。方法:采用免疫组织化学染色的方法检测100例浸润性乳腺癌组织及10例正常乳腺组织标本中STAT5a的表达情况；收集入组乳腺癌患者的临床病理资料，并对所有入组乳腺癌患者进行至少5年的随访；分析STAT5a表达情况与乳腺癌患者临床病理特征、预后的关系。结果:（1）100 例浸润性乳腺癌中STAT5a的阳性表达率为46%，显著高于正常乳腺组织（P<0.05），乳腺癌中STAT5a的表达与肿瘤分级、激素受体状况显著相关（P<0.05）。（2）生存分析显示，STAT5a阳性组乳腺癌患者5年生存率较STAT5a阴性组高，2组比较差异有统计学意义（P<0.05）。（3）单因素分析发现临床分期、淋巴结转移情况、STAT5a与患者5年生存率之间存在关联，并有统计学意义（P<0.05）。（4）Cox回归模型显示：STAT5a、淋巴结转移情况及临床分期是影响乳腺癌患者生存的独立预后因素。结论: 高分化、激素受体阳性乳腺癌组织高表达STAT5a。STAT5a阴性表达的乳腺癌患者预后较差，STAT5a可作为判断乳腺癌患者预后的指标。
AIM:To detect the expression of signal transducer and activator of transcription 5a (STAT5a) in invasive breast cancer tissues, and to analyze the clinical significance of STAT5a in breast cancer patients. METHODS:The expression of STAT5a in 100 cases of invasive breast cancer tissues and 10 cases of normal breast tissues was detected by the method of immunohistochemical staining. The clinical pathological parameters of the breast cancer patients were collected, and were followed up with all the breast cancer patients for at least 5 years. The relationships between the expression of STAT5a and clinic pathological parameters, and prognosis in breast cancer patients were analyzed. RESULTS:The positive expression rate of STAT5a in 100 cases of invasive breast cancer patients was 46%, which was higher than that in the normal breast tissues significantly (P<0.05). The expression of STAT5a in the breast cancer was correlated with the tumor grade and hormone receptor status significantly (P<0.05). According to the result of Kaplan-Meier survival curve analysis and log-rank test, the 5-year survival rate in STAT5a positive group was higher than that in STAT5a negalive group, and the difference between the 2 groups was statistically significant (P<0.05). Single-factor analysis showed that clinical stage, lymph node metastasis and STAT5a existed significant correlations with 5-year survival rates in the breast cancer patients (P<0.05). The Cox regression model showed that lymph node metastasis, clinical stage and STAT5a were independent prognostic factors for survival in the breast cancer patients (P<0.05). CONCLUSION: Compared with poorly differentiated and hormone receptor negative breast cancer, the expression of STAT5a in well-differentiated and hormone receptor positive breast cancer is higher. The patients with STAT5a negative expression have poorer prognosis, suggesting that STAT5a can be used as a prognosis indicator for breast cancer patient.
刘威，龙梅珺，吴珏堃，李玺，邱万寿. STAT5a在乳腺癌组织中的低表达与患者不良预后相关[J]. 中国病理生理杂志, 2014, 30(11): 2004-2008.
LIU Wei, LONG Mei-jun, WU Jue-kun, LI Xi, QIU Wan-shou. Low levels of STAT5a protein in breast cancer are associated with unfavorable clinical outcomes. Chin J Pathophysiol, 2014, 30(11): 2004-2008.
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