Jayaraj Perumal, Sen Seema, Dhanaraj P S, Jhajhria Romika, Singh Shalu, Singh Vijay Kumar
Department of Zoology, Sri Venkateswara College, University of Delhi (South Campus), New Delhi, India.
Department of Ocular Pathology, Dr. R. P. Centre, AIIMS, New Delhi, India.
Indian J Ophthalmol. 2017 Nov;65(11):1109-1113. doi: 10.4103/ijo.IJO_399_17.
Overexpression of the inhibitors of apoptosis proteins have been demonstrated in a variety and of solid tumors including melanomas and nonmelanomas skin cancers. X-linked inhibitor of apoptosis protein (XIAP) is an inhibitor of apoptosis which prevents apoptosis by inhibiting caspases 9, 7, and 3. The prognostic value of XIAP in sebaceous gland carcinoma (SGC) remains unexplored.
The immunohistochemical expression of XIAP was evaluated in 29 SGC cases.
The cytoplasmic overexpression of XIAP was detected in 62% SGC cases. XIAP expression was found to be significantly associated with advanced age, large tumor size, and with reduced disease-free survival (P = 0.0174). XIAP expression and advance tumor Grade III emerged as significant risk factors on univariate analysis. On stepwise multivariate analysis, both increased cytoplasmic XIAP expression and high tumor grade were found to be significantly associated with recurrence. Patients with low XIAP immunoexpression had a longer disease-specific survival than those with high expression in the 5-year follow-up.
The present study demonstrates at the immunohistochemical level that XIAP is overexpressed in SGC and that high expression could be of biological significance in the development of eyelid SGC. Our finding suggests that up-regulation of XIAP may aggravate tumor metastasis in SGC.
凋亡抑制蛋白在包括黑色素瘤和非黑色素瘤皮肤癌在内的多种实体瘤中均有过表达。X连锁凋亡抑制蛋白（XIAP）是一种凋亡抑制剂，通过抑制半胱天冬酶9、7和3来阻止细胞凋亡。XIAP在皮脂腺癌（SGC）中的预后价值仍未得到探索。
对29例SGC病例进行XIAP的免疫组化表达评估。
62%的SGC病例中检测到XIAP的细胞质过表达。发现XIAP表达与高龄、肿瘤体积大以及无病生存期缩短显著相关（P = 0.0174）。在单因素分析中，XIAP表达和肿瘤进展至III级是显著的危险因素。在逐步多因素分析中，细胞质XIAP表达增加和高肿瘤分级均与复发显著相关。在5年随访中，XIAP免疫表达低的患者比高表达患者具有更长的疾病特异性生存期。
本研究在免疫组化水平上证明XIAP在SGC中过表达，且高表达在眼睑SGC的发生发展中可能具有生物学意义。我们的发现表明XIAP的上调可能会加重SGC中的肿瘤转移。
