Background: AAA+ nuclear coregulator cancer associated (ANCCA) is found to be overexpressed in various cancer types and could play a role in common and fundamental cellular processes. A recent study suggested that ANCCA was a likely driver whose expression explained the behavior of differentially expressed proliferation-related genes in lung adenocarcinoma. However, protein expression of ANCCA in lung adenocarcinoma and its association with clinicopathologic parameters and commonly reported driver mutations remains unexplored.
Methods: ANCCA expression was evaluated by immunohistochemistry in 143 surgically resected lung adenocarcinomas and was correlated with clinicopathologic and molecular variables including adenocarcinoma histologic subtypes, tumor, node, metastasis status, relapse-free survival, overall survival, EGFR mutations, KRAS mutations, HER2 mutations and ALK fusions.
Results: Positive ANCCA expression was significantly associated with male sex, smokers, poorly differentiated tumors, nonlepidic predominant subtype, more advanced T stage, lymph nodal metastasis and late disease stage. Cox multivariate analysis revealed that ANCCA-positive expression was an independent predictor of worse relapse-free survival [hazard ratio (HR) 1.736, 95 % confidence interval (CI) 1.075-2.804; P = .024) and overall survival (HR 7.758, 95 % CI 2.955-20.370; P < .001). The addition of ANCCA protein expression to the prognostic model using pathologic stage markedly improved the prognostic accuracy; the concordance index increased from .692 to .788, and the Akaike information criterion decreased from 354.20 to 336.11.
Conclusions: We have identified ANCCA protein expression as a novel independent poor prognostic indicator in lung adenocarcinoma. Prospective studies are warranted to validate its potential prognostic value in combination with the current staging system.