Objective:To analyze the expression of LETM2 in KYSE150 and ECA109 cell lines and its effect on the proliferation, migra-tion, and invasion of esophageal squamous cell carcinoma (ESCC). Methods:The expression level of the LETM2 protein in 90 paired hu-man ESCC tissues and matched adjacent normal tissues was determined through immunohistochemistry. The expression level of LETM2 in ESCC cell lines was detected by real-time PCR and Western blot. The expression levels of LETM2 in KYSE150 and ECA109 cell lines were knocked down using lentivirus. MTT assays were performed to examine the effect of LETM2 on the proliferation of ESCC cells. Colony formation assay was used to detect the colony formation ability. Flow cytometry was performed to analyze the cell cycle. The effect of LETM2 depletion on the migration and invasion of ESCC cells was determined by Transwell assay. Results:LETM2 expres-sion was frequently upregulated in the ESCC tissues than in the adjacent normal tissues. The suppressed exogenous expression of LETM2 led to the inhibition of cell proliferation and colony formation. However, cell migration and invasion were not affected. The re-sults on the cell cycle distribution revealed that LETM2 knockdown acts as a negative regulator of the cell cycle at the G1 to S phase transition. Conclusion:LETM2 acts as a tumor-driven gene in the development and progression of ESCC. This finding suggests that LETM2 can be used as an efficient prognosis biomarker and a potential therapeutic target for ESCC.

Objective: To explore the expression of FAT1 in esophageal squamous cell carcinoma (ESCC) tissues, and its effect on cell proliferation. Methods: The expression levels of FAT1 protein in human ESCC tissues and matched adjacent normal tissues were determined by immunohistochemistry (IHC). Lentivirus based knockdown of FAT1 was carried out in YSE2 and Colo680N cell lines and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide (MTT) assays was performed to examine the effect of FAT1 on the proliferation of these ESCC cells. Colony formation assay was used to detect the colony formation ability. Flow cytometry was performed to analyze the cell cycle and apoptosis. The expression levels of cell cycle markers in FAT1 knock out ESCC cell lines were detected by real-time quantitative reverse transcription polymerase chain reaction(qRT-PCR) and Western blot. Results: The relative expression of FAT1 in ESCC tissues was 66.97±21.53, significantly lower than 78.13±16.76 of adjacent normal tissues(P<0.05). Knockdown of FAT1 promoted cell proliferation and colony formation. In YSE2 cell, the division time in negative control (NC) group was (1 570±51) min, significantly longer than (1 356±31) min in shFAT1 group. In Colo680N cell, division time in NC group was (1 532±53) min, significantly longer than (1 290±30) min in shFAT1 group (P<0.05). Knockdown of FAT1 promoted G1-to S-phase transition and resulted in the upregulation of CDK4/CDK6/CCND1. Conclusion FAT1 inhibits the proliferation and G1-to S-phase transition of ESCC cells through regulating the protein expression of CDK4/CDK6/CCND1 complex.

[摘 要] 目的：探讨内吞作用相关基因FCHO2在各亚型乳腺癌中的表达及其与乳腺癌患者的预后和免疫细胞浸润的相关性。方法：应用免疫组化法和bc-GenExMiner v5.0数据库数据分析FCHO2在各亚型乳腺癌组织中的表达，通过GEO和TIMER数据库数据分析FCHO2与各亚型乳腺癌患者预后和免疫细胞浸润的关系，利用STRING和GEPIA数据库数据分析与FCHO2的互作蛋白网络和其与互作蛋白的相关性，通过UALCAN和DAVID数据库数据对乳腺癌组织中FCHO2表达相关基因进行KEGG和GO分析。结果：免疫组化法结果显示，FCHO2在管腔型和HER2+乳腺癌组织中均呈高表达（均P<0.05），且与HER2和Ki67表达有关联（P=0.03和P=0.007）。FCHO2高表达的管腔型乳腺癌患者总生存期（OS）和无复发生存期（RFS）均明显缩短（均P<0.05）。FCHO2蛋白与EPS15等多种蛋白表达相关且构成蛋白-蛋白互作网络。KEGG和GO分析显示，乳腺癌组织中FCHO2相关表达基因主要与昼夜节律、自噬等生物学过程有关，涉及叉头框蛋白O（FoxO）和TGF-β等信号通路。FCHO2表达与各亚型乳腺癌组织中的免疫细胞浸润相关（均P<0.05）。结论：FCHO2在管腔型、HER2+乳腺癌组织中呈高表达，且与管腔型乳腺癌患者预后及免疫细胞浸润相关，其可能成为乳腺癌治疗的潜在靶点。

[摘 要] 目的：探讨内吞作用相关基因FCHO2在各亚型乳腺癌中的表达及其与乳腺癌患者的预后和免疫细胞浸润的相关性。方法：应用免疫组化法和bc-GenExMiner v5.0数据库数据分析FCHO2在各亚型乳腺癌组织中的表达，通过GEO和TIMER数据库数据分析FCHO2与各亚型乳腺癌患者预后和免疫细胞浸润的关系，利用STRING和GEPIA数据库数据分析与FCHO2的互作蛋白网络和其与互作蛋白的相关性，通过UALCAN和DAVID数据库数据对乳腺癌组织中FCHO2表达相关基因进行KEGG和GO分析。结果：免疫组化法结果显示，FCHO2在管腔型和HER2+乳腺癌组织中均呈高表达（均P<0.05），且与HER2和Ki67表达有关联（P=0.03和P=0.007）。FCHO2高表达的管腔型乳腺癌患者总生存期（OS）和无复发生存期（RFS）均明显缩短（均P<0.05）。FCHO2蛋白与EPS15等多种蛋白表达相关且构成蛋白-蛋白互作网络。KEGG和GO分析显示，乳腺癌组织中FCHO2相关表达基因主要与昼夜节律、自噬等生物学过程有关，涉及叉头框蛋白O（FoxO）和TGF-β等信号通路。FCHO2表达与各亚型乳腺癌组织中的免疫细胞浸润相关（均P<0.05）。结论：FCHO2在管腔型、HER2+乳腺癌组织中呈高表达，且与管腔型乳腺癌患者预后及免疫细胞浸润相关，其可能成为乳腺癌治疗的潜在靶点。