Objective: To investigate the effect of sialic acid combined with immunoglobulin-like lectin 15 (SIGLEC-15) on laryngeal squamous cell carcinoma (LSCC) and underlying mechanisms. Methods: The Cancer Genome Atlas (TCGA), Cancer Cell Line Encyclopedia (CCLE) and Gene Expression Profiling Interactive Analysis (GEPIA2) databases were used for bioinformatics analysis. Cell Counting Kit-8 (CCK8), flow cytometry, and Transwell method were used respectively to detect proliferation, apoptosis, cell cycle, metastasis and invasion behaviors of the cells. Gene chip method was used for detecting up-regulated and down-regulated genes and performing enrichment analysis of differential genes. Western Blotting (WB) and Quantitative Real-time PCR (qPCR) were used to detect the expressions of proteins. Tumor formation experiments in nude mice were used to detect the effect of SIGLEC-15 on the growth of transplanted tumors. Wilcoxon rank sum test, t-test and Log-rank test were used for statistical analysis. Results: SIGLEC-15 was highly expressed in laryngeal squamous cell carcinoma and closely related to life in being. TU686SIGLEC-15-with low expression of SIGLEC-15 was constructed. Compared to TU686SIGLEC-15+, TU686SIGLEC-15-showed significantly reduced activities of proliferation (48 h: 1.32±0.23 vs. 2.56±0.37, t=6.59, P<0.05), migration (1 036.52±51.22 vs. 1 819.62±180.24, t=7.22, P<0.05) and invasion (469.21±112.25 vs. 961.45±102.03, t=7.85, P<0.05); early increased apoptosis ((23.27±1.12)% vs. (5.64±1.61)%, t=11.32, P<0.05); blocked cell cycle at G0/G1 ((59.32±3.65)% vs. (35.46±3.57)%, t=9.85, P<0.05); the knockdown of SIGLEC-15 resulted in up-regulation of 864 genes, down-regulation of 357 genes, with significant changes in molecules of cell cycle, apoptosis and JAK/STAT signal pathways, and the expressions of p-JAK2, p-STAT3, Caspase-3, Bad, Bcl-2, and Cyclin d1 proteins. Tumor formation experiments in nude mice showed that at 8 weeks after the tumors were implanted, the growth transplanted tumors of TU686 SIGLEC-15-cell group was slower than that of TU686 SIGLEC-15+cell group, with significant difference in the mean tumor weights between two groups ((0.382±0.054) g vs. (1.277±0.126) g, t=8.44, P<0.05), while the expression of SIGLEC-15 was lower in the transplanted tumors of SIGLEC-15 knockdown group compared to control group, with significant difference(11.29±2.17 vs. 36.25±7.56, t=9.28, P<0.05). Conclusion: SIGLEC-15 is highly expressed in LSCC and can promote the progression of LSCC through the JAK2-STAT3 pathway.
目的： 探讨唾液酸结合免疫球蛋白样凝集素15（sialic acid-binding immunoglobulin-like lectin 15，SIGLEC-15）对喉鳞状细胞癌（laryngeal squamous cell carcinoma，LSCC）的作用及机制研究。 方法： 应用癌症基因组图谱（The Cancer Genome Atlas，TCGA）、癌细胞系百科全书（Cancer Cell Line Encyclopedia，CCLE）和基因表达谱动态分析（Gene Expression Profiling Interactive Analysis 2，GEPIA2）数据库进行生物信息学分析；应用细胞计数试剂盒（cell counting kit-8，CCK8）、流式细胞术、Transwell法检测其增殖、凋亡、细胞周期、转移及侵袭的变化；应用基因芯片法检测上调及下调的基因，对差异基因进行富集分析；应用蛋白免疫印迹法（WB）和实时荧光定量聚合酶链反应（quantitative real-time PCR，qPCR）检测蛋白表达；裸鼠体内成瘤实验检测SIGLEC-15对喉癌移植瘤生长的影响。采用t检验、Wilcoxon秩和检验、Log-rank检验进行统计学分析。 结果： SIGLEC-15在LSCC中高表达且与生存期密切相关（HR=1.1，P=0.010）。构建低表达SIGLEC-15的细胞模型，即TU686SIGLEC-15-组；与TU686SIGLEC-15+组相比其增殖活性显著降低（48 h：1.32±0.23比2.56±0.37），迁移［（1 036.52±51.22）个比（1 819.62±180.24）个］和侵袭［（469.21±112.25）个比（961.45±102.03）个］能力降低，差异有统计学意义（t值分别为6.59、7.22和7.85，P值均<0.05）。早期凋亡增加［（23.27±1.12）%比（5.64±1.61）%，t=11.32，P<0.05］，细胞周期G0/G1被阻滞［（59.32±3.65）%比（35.46±3.57）%，t=9.85，P<0.05］。敲低SIGLEC-15导致864个基因上调，357个基因下调，细胞周期、凋亡及JAK/STAT信号通路发生显著变化，p-JAK2、p-STAT3、Caspase-3、Bad、Bcl-2、Cyclin d1蛋白分子表达明显变化。裸鼠成瘤结果表明TU686SIGLEC-15-细胞组裸鼠移植瘤增长速度缓慢，种瘤后8周，肿瘤重量分别为（0.382±0.054）g和（1.277±0.126）g，而且SIGLEC-15敲低组移植瘤组织中SIGLEC-15表达更低［（11.29±2.17）比（36.25±7.56）］，差异均有统计学意义（t值为8.44和9.28，P值均<0.05）。 结论： SIGLEC-15在LSCC中高表达并与预后相关，可通过JAK2-STAT3通路促进LSCC的进展。.