The Microsatellite Instability And Loss Of Heterozygosity In Laryngeal Squamous Cell Carcinomas

Laryngeal squamous cell carcinoma(LSCC) is a common malignant neoplasms in head and neck cancer, accounting for 1%-8.4% of human cancer.In recent years,with the increasing tendency of its morbidity and mortality in most regions of the world,LSCC seriously hampers people's health and life.Due to the effects of genetic and environmental factors,the incidence of LSCC is the highest in the country's northeastern region.So rely on the geographical advantage,we study depthly genetic factors about the occurrence and development of laryngeal cancer in molecular genetics.It is of great significance that revealing mechanism of LSCC.Tumor development is closely related to the abnormal chromosome number and structure,analying high frequency of chromosome change of certain tumors will provide positioning information for screening tumor susceptibility gene. Microsatellite is repetitive DNA sequence.It is widely distributed in the genome and closely linked with a number of important genes.Polymorphic microsatellite markers PCR can detect microsatellite genetic markers,LOH and MSI,and then suggests that the vicinity gene be abnormal.Therefore in this study,we analy LOH and MSI in chromosome region of laryngeal cancer by molecular genetics means-polymorphic microsatellite markers PCR technology.Data show, microsatellite aberrations of head and neck squamous cell carcinoma is easier to change in 3p,5q,9p,17p.And the short arm of chromosome 8,especially 8p21-22, in many solid tumors the higher incidence of LOH can be detected in both;Bat26 is a appropriate indicator to identify MSI-H;Incidence of LOH on D9S162 is very high;P53 gene is the highest correlation with the human gene;D17S396 has a smaller polymorphism and is used to detect nm23-H1 Genetic Instability. Therefore,we selected 5 microsatllite polymorphism markers D8S552,D9S162, Bat26,TP53 and D17S396 to detect loss of heterozygosity and microsatellite instability in 38 cases of laryngeal squamous cell carcinoma and explored their correlation with clinicopathological features.In addition to 15 cases and 16 cases did not occur LOH or MSI,23 cases had occurred LOH at least on a locus,the total incidence of LOH was 60.53%;22 cases had occurred MSI at least on a locus,the total incidence of MSI was 57.89%;1 laryngeal carcinoma patient occurred LOH at 3 locus simultaneously,2 patients occurred MSI at 3 locus simultaneously, Accounted for 75% (3/4) of the measured microsatellite loci.On five loci, the LOH frequencies were 23.08%,34.78%, 19.23%,23.08% and 29.17% respectively;The MSI frequencies were 11.54%, 21.74%,30.77%,26.92% and 37.50% respectively.In addition,LOH on D8S552 occured in poorly differentiated laryngeal carcinoma and associated with poor prognosis.MSI on D9S162 can be used as a symbol of a better prognosis in laryngeal carcinoma.In anatomy of typing,LOH on Bat26 was more frequently found in glottic laryngeal carcinoma than Supraglotti(cχ2=9.91,P<0.01),hMSH2 is more frequently deleted in the glottic carcinoma.LOH on D9S162 was corrected with sex,Female patients were a higher frequency of LOH.But,male patients were a higher frequency of LOH on TP53. The results show that the occurrence of LSCC is closely related to D8S552,D9S162,Bat26,TP53 and D17S396.There are a number of potential tumor suppressor genes associated with the occurrence of laryngeal cancer at the D8S552 and D9S162 sites vicinity. nm23H1 and TP53 gene was closely associated with the occurrence of laryngeal cancer.In tumor genetics research,It is a very effective ways and means to find relevant genes by means of molecular genetics and clues of common chromosomal abnormallities in cancer.It will make further study about the molecular mechanism of cancer,which would help us to find target genes for gene diagnosis and gene therapy to cancer,so we can early capture tumor, and then benefit for humanity.