Department of Surgical Oncology, Medical University of Lodz, Copernicus Memorial Hospital, Lodz, Poland.
Neoplasma. 2011;58(5):430-5. doi: 10.4149/neo_2011_05_430.
Smac/DIABLO protein promotes caspase-dependent apoptosis by inhibition of inhibitor of apoptosis protein (IAP) family members. The role of Smac/DIABLO in breast cancer has not been yet established. Therefore, the aim of the study was to assess the expression of this protein in tumor cells from breast cancer patients. The expression of Smac/DIABLO was analyzed in 62 breast cancer patients by flow cytometry. The obtained results were compared with expression of this protein in benign breast tumor tissue, which served as the control (11 patients with fibroadenoma). Expression of caspase-3 proteins in breast cancer was also evaluated. Smac/DIABLO expression in breast cancer was correlated with clinical and pathological data. Although the expression of Smac/DIABLO protein was found in all examined samples of both the breast cancer and fibroadenoma patients, the median expression of Smac/Diablo in breast cancer was significantly lower than in the control (39.1% vs. 48.1%; p=0.0047). Smac/DIABLO expression correlated with expression of caspase-3 (p=0.000008). In pT1 breast cancer patients, expression of Smac/DIABLO protein was higher than in those with pT2-3 (p=0.02). Diffuse cancer infiltration significantly correlated with lower expression of Smac/DIABLO protein (p=0.02). Moreover, there was a loose correlation between low expression of Smac/DIABLO protein and cancer embolus in minor blood and lymphatic vessels (p=0.08). Our results indicate that expression of Smac/DIABLO inversely correlates with the tumor stage, which may suggest that this protein may play an important role in the breast cancer development.
Smac/DIABLO 蛋白通过抑制凋亡抑制蛋白（IAP）家族成员来促进半胱天冬酶依赖性细胞凋亡。Smac/DIABLO 在乳腺癌中的作用尚未确定。因此，本研究旨在评估该蛋白在乳腺癌患者肿瘤细胞中的表达。通过流式细胞术分析了 62 例乳腺癌患者中 Smac/DIABLO 的表达。将获得的结果与良性乳腺肿瘤组织（11 例纤维腺瘤）的表达进行了比较。还评估了乳腺癌中 caspase-3 蛋白的表达。Smac/DIABLO 在乳腺癌中的表达与临床和病理数据相关。尽管在乳腺癌和纤维腺瘤患者的所有检查样本中均发现了 Smac/DIABLO 蛋白的表达，但乳腺癌中 Smac/DIABLO 的中位表达明显低于对照组（39.1%比 48.1%；p=0.0047）。Smac/DIABLO 表达与 caspase-3 表达相关（p=0.000008）。在 pT1 期乳腺癌患者中，Smac/DIABLO 蛋白的表达高于 pT2-3 期患者（p=0.02）。弥漫性癌浸润与 Smac/DIABLO 蛋白表达降低显著相关（p=0.02）。此外，Smac/DIABLO 蛋白低表达与小血管和淋巴管中癌栓之间存在松散相关（p=0.08）。我们的结果表明，Smac/DIABLO 的表达与肿瘤分期呈负相关，这表明该蛋白可能在乳腺癌的发展中发挥重要作用。
