ABSTRACT
Objective To observe expression changes of the telomeric repeat binding factor 2 (TRF2) in mouse cortical neurons during aging and its biological significance.Methods TRF2 expression in cortical neurons of young (2 months) and old (20 months) C57BL/6J mice were tested by Western blot and real time PCR.pcDNA-TRF2 was transfected in embryonal cortical neurons.Neurons viability was determined by MTT after exposure to camptothecin for 16 h.Results TRF2 expression decreased significantly in cortical neurons in old mice than that in young mice.After exposure to camptothecin for 16 h,(75.4±2.6) ％ of pcDNA TRF2 transfected neurons were viable and the transfection rate was higher in pcDNA-TRF2 transfected neurons than in control transfected neurons [(32.6 ± 9.3) ％] (t =22.85,P ＜ 0.05).Conclusions TRF2 expression decreases significantly in aging mouse,downregulation of TRF2 may participate in neurons aging,and TRF2 overexpression may be a potential therapeutic target against neurodegeneration.
ABSTRACT
OBJECTIVE To study the significance by analyzing the expression of human protection of telomeres1(POT1)and telomeric repeatbinding factor-2(TRF2)in the tissues of laryngneal squamous cell carcinoma(LSCC)and in polyp of vocal cord tissues. METHODS The expression of POT1 and TRF2 in 20 tumor samples and 19 polyp of vocal cord were determined by the indirect immunofluorescence method. The results were scored and analyzed statistically. RESULTS The positive expression rates of POT1 and TRF2 in tumor samples was 65.00% and 70.00% respectively. There were no positive expression of POT1 and TRF2 in polyp of vocal cord. The positive expression of POT1 was higher in poorly differentiated laryngeal carcinoma than that in well-differentiated and moderately differentiated laryngeal carcinoma(Chi-square test with contingency table, P0.05). CONCLUSION The expression of POT1 and TRF2 in laryngneal squamous cell carcinoma were remarkable, POT1 and TRF2 may play a critical role in tumorigenesis of laryngneal squamous cell carcinoma. There was statistical significant difference for degrees of POT1 expression in different tumor histological grades.