lncRNA DGCR5通过上调EGFR表达促进食管鳞状细胞癌TE1细胞的恶性生物学行为

目的：探讨长链非编码 RNA（long non-coding RNA，lncRNA）DiGeorge 综合征临界区基因 5（digeorge syndrome critical region gene 5，DGCR5）对食管鳞状细胞癌（esophageal squamous cell carcinoma，ESCC）TE1细胞增殖、迁移和侵袭的影响及其机制。方法：采用qPCR检测ESCC细胞系 TE1、Yes-2、KYSE150 和 Eca9706 中 DGCR5 的表达水平。将siRNA-DGCR5（si-DGCR5）和阴性对照组（si-NC）质粒转染进TE1细胞，用CCK-8、划痕愈合、Transwell小室法分别检测TE1细胞增殖、迁移和侵袭能力。依据GEPIA数据库资料分析食管癌组织中 DGCR5 表达与细胞表皮生长因子受体（epidermal growth factor receptor，EGFR）的相关性，并用qPCR和Western blotting（WB）检测ESCC细胞系中EGFR mRNA和蛋白表达水平，进一步用WB实验检测转染 si-DGCR5 前后 TE1细胞中EGFR蛋白的表达水平。结果：DGCR5 在 ESCC 细胞系中均高表达（均 P<0.01），转染siDGCR5组TE1细胞中DGCR5的表达水平明显低于si-NC组（P<0.01）。敲低DGCR5后,TE1细胞的增殖、侵袭和迁移能力显著低于si-NC组细胞（均 P<0.01）。GEPIA 数据库的分析显示，食管癌组织中 DGCR5 表达水平与 EGFR 的表达呈正相关（P<0.01）。敲低DGCR5后TE1细胞中EGFR蛋白表达水平明显下降（P<0.01）。结论：lncRNA DGCR5在ESCC细胞中呈高表达，可能通过上调EGFR表达来促进TE1细胞的增殖、侵袭和迁移等恶性生物学行为。

lncRNA DGCR5 promotes the malignant biological behaviors of esophageal squamous cell carcinoma TE1 cells by up-regulating EGFR expression

Objective: To investigate the effect of long non-coding RNA DiGeorge syndrome critical region gene 5 (DGCR5) on proliferation, invasion and migration of esophageal squamous cell carcinoma (ESCC) TE1 cells and its mechanism. Methods: qPCR was used to detect the expression level of DGCR5 in ESCC cell lines (TE1, Yes-2, KYSE150 and Eca9706). TE1 cells were transfected with siRNA-DGCR5(si-DGCR5) and negative control (si-NC) plasmids, respectively. CCK-8, Wound healing and Transwell assay were used to detect the proliferation, migration and invasion of TE1 cells before and after DGCR5 knockdown. The relationship between DGCR5 expression and epidermal growth factor receptor (EGFR) in ESCC tissues was analyzed by GEPIA database. The mRNA and protein expressions of EGFR in ESCC cell line were examined by qPCR and Western blotting (WB). WB was further used to detect the expression of EGFR protein in TE1 cells before and after DGCR5 knockdown. Results: lncRNA DGCR5 was highly expressed in ESCC cell lines (all P<0.01). qPCR confirmed that the expression of DGCR5 in TE1 cells of si-DGCR5 group was significantly lower than that of si-NC group (P<0.01). The proliferation, migration and invasion ability of TE1 cells in si-DGCR5 group were significantly lower than those in si-NC group (all P<0.01). GEPIA database showed that the expression of DGCR5 was positively correlated with EGFR in ESCC tissues (P<0.01). WB showed that the protein level of EGFR in TE1 cells of si-DGCR5 group decreased significantly (P<0.01). Conclusion: lncRNA DGCR5 is highly expressed in ESCC cells, and promotes the proliferation, invasion and migration of TE1 cells possibly by up-regulating EGFR expression.