Expression of the protein gene product 9.5, PGP9.5, is correlated with T-status in non-small cell lung cancer

Background: In a tumor, increased deubiquitination of cyclins by a protein gene product gene, PGP9.5, could contribute to the uncontrolled growth of somatic cells that is a hallmark of cancer. We hypothesized that PGP9.5 may be expressed in tumors of patients with non-small cell lung cancer (NSCLC). Methods: Expression of PGP9.5 messenger RNA was evaluated by reverse transcription polymerase chain reaction (RT-PCR) in 95 non-small cell lung carcinomas and adjacent histological normal lung samples. The data were analyzed with reference to clinicopathological factors. Results: PGP9.5 transcripts were detected in 18 (12.8%) of the tumor samples, although some of paired normal lung samples showed very weak expression. There was no relationship between PGP9.5 gene expression and age, gender, N-status or pathological subtype. PGP9.5 gene was preferentially expressed in T3/T4 NSCLC (12/41, 29.3%) compared with T1/T2 NSCLC (6/54, 11.1 %) (p = 0.0482). Conclusions: Although the PGP9.5 gene was not expressed in a majority of NSCLC tumors, we suggest that PGP9.5 may correlate with tumor invasion or progression of NSCLC.