Expression And Significance Of Chemokines CXCL12 And Its Receptor CXCR4, CXCR7 In Laryngeal Squamous Cell Carcinoma

Objective: The incidence of laryngeal cancer gradually increased in recent years, laryngeal cancer is derived from epithelial tissues of laryngeal cancer,it is a common malignant tumor in Otolaryngology- Head and Neck Surgery. The occurrence, development, invasion and metastasis of cancer is a very complex process, laryngeal cancer also true, it participates involving multiple genes and multiple factors, it is the interaction results of activation of oncogenes,runaway of apoptotic genes,inactivation of tumor suppressor genes and other factors. Chemokine CXCL12 namely pre-B cell stimulating factor, stromal cells source factor derived factor,it plays an important role in the process of the proliferation 、 transfer and angiogenesis in tumor cell.CXCR4,CXCR7 are both receptors of CXCL12. CXCR4 is highly conserved seven transmembrane G protein-coupled receptors, CXCL12- CXCR4 biological axis play an important role of the proliferation growth, invasion and metastasis in a variety of tumor. CXCR7 also belongs to the G protein coupled receptors, it plays an important role in the development of various malignant tumors and angiogenesis. Similarly, CXCL12-CXCR7 biological axis also involved in the proliferation, in the growth, invasion and metastasisa of various tumors. This study is to take the laryngeal squamous cell carcinoma as the research object, investigate the expression of CXCL12, CXCR4, CXCR7 in the adjacent normal mucosa and LSCC, further understand the relationship between these three and their respective roles in the occurrence, development, invasion and metastasis of LSCC,provide new research directions for the treatment and prognosis of laryngeal squamous cell carcinoma.Methods:1 Immunohistochemistry(streptavidin-perosidase) was employed to measure the protein expression of CXCL12,CXCR4 and CXCR7 in 39 specimens of laryngeal squamous cell carcinoma tissue and 25 specimens of adjacent tissue, and further analyzed these three relationships of tumor stage, histologic grade,and patients’ age, gender,smoking history,drinking history in laryngeal squamous cell carcinoma.2 Statistics analysis: SPSS 18.0 was applied to analyze the results of experiment. Using Chi-square test to compare the differences between different groups, using Pearson correlation method to analysis of correlation between each two indexes. Data were considered statistically significant difference when P≤0.05, very significant difference when P≤0.01, positive correlations when r>0.3.Results:1 In the adjacent normal mucosa and LSCC, Expression of CXCL12 and its relationship with clinical parameters.Immunohistochemistry was employed to measure the expression of CXCL12 in 25 specimens of adjacent tissue and 39 specimens of laryngeal squamous cell carcinoma tissue. The positive expression rate of CXCL12 protein were 32.00%( 8/25) and 84.62%( 33/39), the latter was significantly higher than the former,there have been very significant difference statistically significance(P<0.01). The protein expression of CXCL12 in adjacent normal laryngeal mucosa was significantly lower than in laryngeal squamous cell carcinoma.CXCL12 protein expression and clinical stage, lymph node metastasis, tumor pathology grading related in LSCC(P<0.05),and with age, clinical type, smoking, drinking grouping unrelated(P>0.05).2 In the adjacent normal mucosa and LSCC, Expression of CXCR7 and its relationship with clinical parameters.Immunohistochemistry was employed to measure the expression of CXCR7 in 25 specimens of adjacent tissue and 39 specimens of laryngeal squamous cell carcinoma tissue. The positive expression rate of CXCR7 protein were 40.00%(10/25)and 82.05%(32/39), the latter was significantly Methods: higher than the former,there have been very significant difference statistically significance(P<0.01). The protein expression of CXCR7 in adjacent normal laryngeal mucosa was significantly lower than in laryngeal squamous cell carcinoma. CXCR7 protein expression and clinical stage, lymph node metastasis, tumor pathology grading related in LSCC(P<0.05),and with age, clinical type, smoking, drinking grouping unrelated(P>0.05).3 In the adjacent normal mucosa and LSCC, Expression of CXCR4 and its relationship with clinical parameters.Immunohistochemistry was employed to measure the expression of CXCR4 in 25 specimens of adjacent tissue and 39 specimens of laryngeal squamous cell carcinoma tissue. The positive expression rate of CXCR4 protein were 28.00%(7/25) and 84.62%(33/39), the latter was significantly higher than the former,there have been very significant difference statistically significance(P<0.01). The protein expression of CXCR4 in adjacent normal laryngeal mucosa was significantly lower than in laryngeal squamous cell carcinoma.CXCR4 protein expression and clinical stage, lymph node metastasis, tumor pathology grading related in LSCC(P<0.05),and with age, clinical type, smoking, drinking grouping unrelated(P>0.05).4 Correlations: In laryngeal squamous carcinoma tissues,there were positive correlations between the expressions of CXCL12 and CXCR7(P<0.01, r=0.541),the same is between the expression of CXCL12 and CXCR4(P<0.05,r=0.409), but no significant correlations between the expressions of CXCR4 and CXCR7(P>0.05,r=0.171).Conclusions:1 CXCL12, CXCR7 and CXCR4 are all expressed in laryngeal squamous cell carcinoma and specimens of adjacent tissue.2 CXCL12, CXCR7 and CXCR4 are highly expressed in laryneal squamous cell carcinoma, described the three may be involved in the occurrence of laryngeal squamous cell carcinoma.3 In laryngeal squamous cell carcinoma tissues, the higher expression of CXCL12, CXCR7 and CXCR4 was correlated with lymph node metastasis, clinical stage and pathological grading of tumor, but that wasn’t correlated with patients’ clinical classification, age,smoking history and drinking history. The three may participate in the occurrence, development and metastasis of laryngeal squamous cell carcinoma.4 There was a significant positive correlation between CXCL12 and CXCR7, CXCL12 and CXCR4 in laryngeal squamous cell carcinoma. The Biological axis of CXCL12-CXCR7 and CXCL12-CXCR4 may have synergy, and may depend on each other in the occurrence, infiltration and metastasis of laryngeal squamous carcinoma.