Expression and prognostic roles of PABPC1 in esophageal cancer: correlation with tumor progression and postoperative survival.

The prognosis of patients with esophageal cancer remains poor. TNM classification is not sufficient to predict their prognosis, and novel predictive markers of the prognosis of esophageal cancer patients are therefore needed. Poly A binding protein, cytoplasmic 1 (PABPC1) plays a role in post-transcriptional control of mRNA and may be involved in tumorigenesis. PABPC1 expression has not been studied in esophageal cancer. Expression of PABPC1 was quantified by real-time reverse transcription polymerase chain reaction (RT-PCR) using LightCycler in 41 primary esophageal squamous cell carcinomas (ESCCs) and their paired normal esophageal mucosa. We examined the correlation between PABPC1 expression and the clinicopathological factors and prognosis of ESCC patients. Reduced expression of PABPC1 was accompanied by locally invasive tumors (t-factor, p=0.0145) and more advanced tumors (pathologic stage, p=0.0264). Moreover, ESCC patients with low PABPC1 mRNA expression had a significantly shorter postoperative survival time than those with high expression (median survival, 3.1 vs. 6.5 months, p=0.002). In esophageal cancer, reduced expression of PABPC1 was correlated with local tumor progression and poor prognosis after surgery.