Correlation of hENT1 expression with response and survival in non-small cell lung cancer patients treated with gemcitabine-containing chemotherapy

Abstract

e22032 Background: The most active gemcitabine uptake has been found via the human equilibrative nucleoside transporter 1 (hENT1). This study was to explore the prognostic impact of the hENT1 on response and survival in Non-small lung cancer (NSCLC) patients treated with gemcitabine-containing chemotherapy. Methods: We developed polyclonal antibody for hENT1. Then we stained hENT1 expression by immunohistochemical analysis in 24 biopsy samples of NSCLC which was formaline-fixed, paraffin- embedded tissues. We were treated with gemcitabine alone or gemcitabine-containing chemotherapy until third-line regimen. Results: They comprised 16 males and 8 females with a median age of 63 years (range 45–82 years). Seventeen patients had adenocarcinomas, six had squamous-cell carcinomas, and one had a large-cell carcinoma. All patients were treated with gemcitabine- containing chemotherapy, with 9, 12, and 3 patients receiving this as a first-, second-, and third-line therapy, respectively. The hENT1-positive staining in NSCLC samples was significantly associated with response to gemcitabine-containing chemotherapy (Fisher's exact test, P<0.05). Responses to gemcitabine-containing chemotherapy were evident in none of the seven patients with no hENT1 expression. Further 3 years survival differed by hENT1 staining: 714 days for hENT1-positive, 316 days for hENT1-negative (HR 2.86; 95%CI 1.13–15.16, P<0.05). Conclusions: While there are some determinants for gemcitabine sensitivity, hENT1 expression may be a predictive maker for the response and survival to gemcitabine-containing chemotherapy in NSCLC. No significant financial relationships to disclose.