Involvement of p29/SYF2/fSAP29/NTC31 in the progression of NSCLC via modulating cell proliferation.

p29, also known as SYF2/fSAP29/NTC31, is a protein associated with chromatin and involved in DNA damage response, cell cycle arrest and pre-mRNA splicing. In p29-depleted cells, DNA replication was reduced and cell population in G1 phase increased. In this study, we investigated the potential role of p29 in the regulation of non-small cell lung cancer (NSCLC) progression. Western blot and immunohistochemistry staining showed that p29 was up-regulated in clinical NSCLC tissues compared with adjacent non-cancerous tissues, and the expression of p29 had a positive correlation with clinical stage and histological differentiation, as well as expression of Ki-67, a proliferating marker. Kaplan-Meier analysis indicated that patients with high level of p29 expression had poor overall survival. In addition, small interfering RNA of p29 was performed, and the effects on NSCLC growth were examined. Interference of p29 blocked S phase entry, inhibited proliferation of A549 cells and up-regulated level of p21 expression. Taken together, these results suggested that p29 might contribute to the progression of NSCLC by enhancing cell proliferation, implicating that targeting p29 might provide beneficial effects on the clinical therapy of NSCLC.