[Correlations of biomolecular markers, such as P53 protein and vascular endothelial growth factor, to radiosensitivity of nasopharyngeal carcinoma].

Background & Objective: About 20%-40% nasopharyngeal carcinoma (NPC) patients, who are in the same staging group, receiving the same treatment modality and radiotherapy dose, relapse in the irradiated fields within 5 years. This is mainly due to the differences in internal radiosensitivity. This study was to analyze the proliferation, apoptosis, angiogenesis, and lymphogenesis of tumor cells, and to explore the correlation of these factors to radiosensitivity.

Methods: P53 protein, vascular endothelial growth factor (VEGF) protein, survivin protein, VEGF-C protein, Ki67 protein, and microvascular density (MVD) of 60 biopsy samples from radiosensitive group and 60 from radio-resistant group were detected by immunohistochemistry, respectively. Their correlations to clinical characteristics were analyzed.

Results: The positive rates of P53, VEGF, survivin, VEGF-C, Ki67 were 65.0%, 57.5%, 60.8%, 42.5%, 57.5%, respectively. The positive rates of P53 and VEGF, and MVD in the radio-sensitive group and in the radio-resistant group were (25.97+/-21.26)%, (18.50+/-19.86)%, 32.65+/-19.61 and (37.85+/-28.67)%, (30.83+/-23.94)%, 41.95+/-16.97, respectively (P<0.05). The positive rates of Survivin, VEGF-C, and Ki67 between the two groups had no statistic difference (P>0.05). The correlations between P53, VEGF, and MVD were obvious.

Conclusion: P53 protein, VEGF protein and MVD might be biomolecular markers for evaluating the internal radiosensitivity of NPC patients.