DNA Ligase4 as a Prognostic Marker in Nasopharyngeal Cancer Patients Treated with Radiotherapy

• DOI: 10.7314/apjcp.2014.15.24.10985
• Publication Date: 2015-03-03T08:53:20Z
• Authors: Dong Hyun Kim; Sung Yong Oh; So Yeon Kim; Seul Lee; Myeong Seok Koh; Ji Hyun Lee; Suee Lee; Sung-Hyun Kim; Heon Soo Park; Won Joo Hur; Jin Sook Jeong; Mi Ha Ju; Young Mi Seol; Young-Jin Choi; Joo Seop Chung; Hyo-Jin Kim
• Keywords: Adult; Aged, 80 and over; Male; Nasopharyngeal Carcinoma; Adolescent; DNA Ligases; Carcinoma; Nasopharyngeal Neoplasms; Chemoradiotherapy; Middle Aged; 3. Good health; Immunoenzyme Techniques; DNA Ligase ATP; 03 medical and health sciences; 0302 clinical medicine; Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Carcinoma, Squamous Cell; Humans; Female; Neoplasm Recurrence, Local; Aged; Follow-Up Studies

The capability for DNA double-strand breaks (DSBs) repair is crucial for inherent radiosensitivity of tumor and normal cells. We have investigated the clinicopathologic significance of DNA repair gene expression in nasopharyngeal (NP) carcinoma.A total of 65 NP cancer patients who received radiotherapy were included. The immunopositivity to Ku 70, DNA-PKcs, MRN, RAD50, XRCC4, and LIG4 were examined in all tumor tissues.The patients comprised 42 males and 23 females, with a median age of 56 years (range, 18-84). The expression levels of RAD50 (0,+1,+2,+3) were 27.7%, 32.3%, 21.5%, and 18.5%. LIG4 (±) were 43.1% and 56.9% respectively. The 5-year OS rate of patients with LIG4 (±) were 90% and 67.9%, respectively (p=0.035). The 5-year TTP rate of patients with LIG4 (±) were 75.9%, 55.5%, respectively (P=0.039).Our results suggest the possibility of predicting the radiosensitivity of NP cancer by performing immunohistochemical analysis of LIG4.