Loss of expression of MHC class I-related chain A (MICA) is a frequent event and predicts poor survival in patients with hepatocellular carcinoma.

Abstract

Natural killer (NK) cells are important effector cells for the first line of defense against tumor. Distant MHC class I homolog MICA has been identified as human ligand for NK cell activating receptor NKG2D. Engagement of MICA triggers NK cells and augments antigen-specific CTL anti-tumor immunity. However, the expression level of MICA and its clinical significance in hepatocellular carcinoma remains to be elucidated. In the present study, a hospital-based study cohort of 143 HCC patients was involved. MICA expression levels were determined by immunohistochemical staining. The association of MICA expression with tumor clinicopathologic features, disease-free survival, and overall survival of HCC patients were analyzed. Significantly decreased expression of MICA was detected in tumor specimens. MICA expression was significantly associated with AFP level (P < 0.001) and tumor node metastasis stage (P = 0.003). Patients with reduced level of MICA had a statistically significantly shorter disease-free survival and overall survival duration than patients with preserved expression of MICA. However, in multivariate analysis, MICA expression level was found not to be an independent prognostic factor for both disease-free survival and overall survival of HCC patients. Our findings suggest that decreased MICA expression may play an important role in HCC tumor evasion of host immunity, which warrants further investigation in future studies.

• Authors: Jie Zhang, Zhuding Xu, Xingchun Zhou, Haibin Zhang, Ning Yang, Yousheng Wu, Yibing Chen, Guangshun Yang, Tingting Ren
• Journal: International journal of clinical and experimental pathology (Int J Clin Exp Pathol) Vol. 7 Issue 6 Pg. 3123-31 ( 2014) ISSN: 1936-2625 [Electronic] United States
• PMID: 25031731 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Biomarkers, Tumor
• Histocompatibility Antigens Class I
• MHC class I-related chain A

Topics

• Adult
• Aged
• Biomarkers, Tumor (analysis)
• Carcinoma, Hepatocellular (immunology, mortality, pathology)
• Disease-Free Survival
• Female
• Histocompatibility Antigens Class I (analysis, biosynthesis)
• Humans
• Immunohistochemistry
• Kaplan-Meier Estimate
• Liver Neoplasms (immunology, mortality, pathology)
• Male
• Middle Aged
• Prognosis
• Proportional Hazards Models
• Tumor Escape (immunology)