Z Li1, Y Zong. 1. Department of Pathology, Sun Yat-sen University of Medical Sciences, Guangzhou 510089.
Abstract
OBJECTIVE: To investigate the effects of LMP-1 expression on neoplastic cell proliferation and apoptosis in untreated nasopharyngeal carcinoma (NPC). METHODS: Biopsies from 55 untreated NPC cases were collected. EBERs was detected by in situ hybridization. PCNA, LMP-1 and bcl-2 were detected by immunohistochemistry method. Cell apoptosis was demonstrated by TUNEL (TdT-mediated dUTP-x nick end labeling) kit. RESULTS: (1) The positive LMP-(1) expression rate was 27/55 (49.1%). The median PI (PCNA Index) of LMP-1 positive cases (90.0%) was higher than that of LMP-1 negative cases (80.0%) and the p value was less than 0.05 by rank sum (rs) test. (2) The median TI (TUNEL Index) of LMP-1 positive cases (16.2 per high power field) was also higher than that of LMP-1 negative cases (10.4 per high power field) and the p value was less than 0.05 by rs test. (3) As for the bcl-2 expression percentages, no correlation was found between LMP-1 positive and negative cases. (4) A positive rank correlation existed between PI and TI (rs = 0.368 1, P < 0.01), but no correlation was found between TI and bcl-2 expression percentage. CONCLUSIONS: (1) NPC with LMP-1 expression have higher levels of PI, maybe resulting from the promotional effect of LMP-1 on cell proliferation. (2) NPC with LMP-1 expression also have a higher level of TI, indicating that LMP-1 can induce cell apoptosis, which could not be blocked by bcl-2 expression. The authors suggest that LMP-1 expression may exert a dual action on neoplastic cell proliferation and apoptosis in untreated nasopharyngeal carcinoma.
OBJECTIVE: To investigate the effects of LMP-1 expression on neoplastic cell proliferation and apoptosis in untreated nasopharyngeal carcinoma (NPC). METHODS: Biopsies from 55 untreated NPC cases were collected. EBERs was detected by in situ hybridization. PCNA, LMP-1 and bcl-2 were detected by immunohistochemistry method. Cell apoptosis was demonstrated by TUNEL (TdT-mediated dUTP-x nick end labeling) kit. RESULTS: (1) The positive LMP-(1) expression rate was 27/55 (49.1%). The median PI (PCNA Index) of LMP-1 positive cases (90.0%) was higher than that of LMP-1 negative cases (80.0%) and the p value was less than 0.05 by rank sum (rs) test. (2) The median TI (TUNEL Index) of LMP-1 positive cases (16.2 per high power field) was also higher than that of LMP-1 negative cases (10.4 per high power field) and the p value was less than 0.05 by rs test. (3) As for the bcl-2 expression percentages, no correlation was found between LMP-1 positive and negative cases. (4) A positive rank correlation existed between PI and TI (rs = 0.368 1, P < 0.01), but no correlation was found between TI and bcl-2 expression percentage. CONCLUSIONS: (1) NPC with LMP-1 expression have higher levels of PI, maybe resulting from the promotional effect of LMP-1 on cell proliferation. (2) NPC with LMP-1 expression also have a higher level of TI, indicating that LMP-1 can induce cell apoptosis, which could not be blocked by bcl-2 expression. The authors suggest that LMP-1 expression may exert a dual action on neoplastic cell proliferation and apoptosis in untreated nasopharyngeal carcinoma.