Expression Of BRAF Oncogene In Melanoma In Xinjiang Region

Melanoma is a typically malignant tumor which is origined from epidermal melanocytes, ithas the clinical features of strong metastasis、 rapid development、 poor prognosis and highmortality rate. Studies have shown that hereditary factors are closely related with melanomaincidence. BRAF of the RAS-RAF-MEK-ERK pathway has become the hot gene of melanomatargeted therapy research at present.Objective: To analyze the relationship between BRAF Copy number Gain and BRAF mutationand protein expression, further explore the mechanism of BRAF in melanoma. investigated theexpression of BRAFV600E mutation protein in Xinjiang region melanoma, and comparative studyof different nationalities. To analyze the sensitivity and specificity of immunohistochemistry (IHC)analysis the BRAFV600E mutation in patients with Melanoma. Provide a theoretical basis for theclinical application of VE1, Guide the patients with melanoma to selection the targeted therapydrug.Methods：Part One This study involved formalin-fixation and paraffin-embedding tissue samplesfrom30cases melanoma patients including19cases BRAF mutation patients and20cases BRAFprotein expression positive patients and10case of nevus paraffin-embedded tissue sections inPeople’s Hospital of Xinjiang Uygur Autonomous Region. To detect BRAF gene copy numbergain by FISH, analyze the relationship between BRAF Copy number Gain and BRAF mutationand protein expression. Part Two Select the People’s Hospital of Xinjiang Uygur AutonomousRegion2004-2013pathologically confirmed103cases of melanoma paraffin-embedded tissue andanalyzed with clinical data, and the other40cases of paraffin-embedded tissue nevi as controls.Immunohistochemistry was used to detect BRAF V600E mutant protein expression in melanomatissue and tissue nevi situation. The relationship between BRAF V600E mutant protein expressionand clinical phenotype was analyzed by x2test according to the SPSS17.0Software, statisticalsignificance was considered when P <0.05.Results：1) FISH detected30cases melanoma and10cases nevi tissue, showed that five casesof melanoma have BRAF copy number gain including2cases BRAF amplification and3cases ofchromosome7polyploidy. BRAF copy number gain in nevi not detected.2)The positive level ofBRAF V600E mutation protein in melanoma is20.4%，while it was5.0%in control group, Theexpression levels of BRAF V600E mutation protein in melanoma were significantly higher thanthat in nevus(X2=5.055,P <0.05).3)The expression levels of BRAFV600E mutant protein inmelanoma vary with age, ethnicity, disease location and Clark. The difference was statisticallysignificant (P <0.05). There was no significant correlation with Gender, lymph node metastasis(P>0.05).4)The antibody had a sensitivity of100%(15/15) and a specificity of98.5%(65/66) fordetecting the presence of a BRAF V600E mutation.Conclusion:1) BRAF copy number gain may represent an alternative mechanism in t Oncogeneactivation, often accompanied by BRAF V600E mutation. polyploid chromosome7is amechanism of BRAF amplification and BRAF protein expression increased.2）BRAFV600E mutation specific antibodies in clinical applications is a valuable addition to the traditionalmutation detection, can be used as an ancillary tool to assess the BRAFV600E mutation status inmelanoma.