Background: Amplification of the chromosome 3q seems to occur frequently in esophageal squamous cell carcinoma (ESCC). This study analyzed the clinical effect of messenger RNA (mRNA) expression for PIK3CA (the gene that encodes phosphatidylinositol-3 kinase catalytic alpha-polypeptide) and TFRC (the gene that encodes the transferrin receptor), which map within chromosome 3q in ESCC.
Methods: Formalin-fixed, paraffin-embedded ESCC tissues were examined. Total RNAs were extracted, and reverse transcription products were subjected to polymerase chain reaction amplification of beta-actin, PIK3CA, and TFRC.
Results: Expression of beta-actin mRNA was detected in 67 (55.8%) of 120 samples, with PIK3CA mRNA expression in 22 (32.8%) of these 67 samples and TFRC mRNA expression in 15 (22.4%) of the 67 samples. PIK3CA mRNA expression correlated with regional lymph node metastasis (P = .04). TFRC mRNA expression correlated with distant metastasis (P = .04). Patients with positive results for either PIK3CA or TFRC mRNA displayed a significantly worse prognosis than patients with negative results (PIK3CA, P = .045; TFRC, P = .009). TFRC mRNA expression represented an independent prognostic factor in multivariate analysis (P = .0233), but PIK3CA did not (P = .7585).
Conclusions: PIK3CA and TFRC mRNA represent prognostic factors in patients with ESCC. TFRC mRNA offers an independent prognostic factor, and expression may have clinically important implications.