Amplification And Expression Of PIN1 Gene In Human Laryngeal Squamous Cell Carcinoma

ObjectiveTo investigate the role of PIN1 gene amplification and overexpression in the genesis and development of laryngeal squamous cell carcinoma(LSCC).Material and MethodsLaryngeal squamous cell carcinoma(LSCC)tissues and paired normal tissues were taken from 40 patients without previous chemotherapy or radiotherapy.In the 40 cases,PIN1 gene amplification was detected by differential PCR and cytogenetics approach.PIN1 mRNA level was evaluated by reverse transcription polymerase chain reaction(RT-PCR)withβ-actin as internal control,and PIN1 protein level was detected by immunohistochemistry and Western Blot methods.Statistical analysis was performed using SPSS13.0.ResultsIn 40 cases,PIN1 gene amplification rate was 22.5%(9/40),while 33.33%(3/9) was found to have an increase of 19 chromosome.The rate of mRNA overexpression was 67.5%(27/40).The PIN1 toβ-actin ratio of mean integrated optic dencity was 1.220±0.490 in the cancer tissues,and 0.790±0.154 in the paired normal tissues.PIN1 protein was obviously upregulated,the ratio was 72.5%(29/40)detected by immunohistochemistry,65%(26/40)detected by Western Blot.Through spearman correlation analysis,it was found that there was a high consistency between PIN1 gene amplification and mRNA,protein overexpression in laryngeal carcinoma tissue. Statistical analysis showed that there was no significant correlation of PIN1 gene amplification and overexpression with the differentiated degree and clinical pathological stage of laryngeal carcinoma.ConclusionThese data suggested that there was a positive correlation between PIN1 gene overexpression and its DNA amplification.PIN1 overexpression may play an essential role in the very early stage of the laryngeal carcinoma genesis,and promote its progession through multiple pathways.This paper may implicate that PIN1 gene DNA amplification is one reason for the gene overexpression.Therefore,supression of this target gene will be an efficient method to block the development of laryngeal carcinoma,and thereby help us to achieve the effective gene therapy.