Comparative proteomics and global genome-wide expression data implicate role of ARMC8 in lung cancer


Background: Cancer loci comprise heterogeneous cell populations with diverse cellular secretions. Therefore,disseminating cancer-specific or cancer-associated protein antigens from tissue lysates could only be marginallycorrect, if otherwise not validated against precise standards. Materials and
Methods: In this study, 2DE proteomicprofiles were examined from lysates of 13 lung-adenocarcinoma tissue samples and matched against the A549cell line proteome. A549 matched-cancer-specific hits were analyzed and characterized by MALDI-TOF/MS.
Results: Comparative analysis identified a total of 13 protein spots with differential expression. These proteinswere found to be involved in critical cellular functions regulating pyrimidine metabolism, pentose phosphatepathway and integrin signaling. Gene ontology based analysis classified majority of protein hits responsible formetabolic processes. Among these, only a single non-predictive protein spot was found to be a cancer cell specifichit, identified as Armadillo repeat-containing protein 8 (ARMC8). Pathway reconstruction studies showed thatARMC8 lies at the centre of cancer metabolic pathways.
Conclusions: The findings in this report are suggestiveof a regulatory role of ARMC8 in control of proliferation and differentiation in lung adenocarcinomas.