Kawabe Nozomi, Matsuoka Kohei, Komeda Kazuki, Muraki Nao, Takaba Miho, Togami Yasuha, Ito Yumeno, Yamada Mizuki, Sunaga Noriaki, Girard Luc, Minna John D, Cai Ling, Xie Yang, Tanaka Ichidai, Morise Masahiro, Sato Mitsuo
Division of Host Defense Sciences, Department of Integrated Health Sciences, Nagoya University Graduate School of Medicine, Nagoya, Aichi 461-8673, Japan.
Department of Respiratory Medicine, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550, Japan.
Oncol Lett. 2023 Jul 25;26(3):391. doi: 10.3892/ol.2023.13977. eCollection 2023 Sep.
Grainyhead-like 2 (GRHL2) is a transcription factor that suppresses epithelial-to-mesenchymal transition (EMT). It has been previously shown that GRHL2 can confer both oncogenic and tumor-suppressive roles in human cancers, including breast, pancreatic and colorectal cancers. However, its role in lung cancer remains elusive. In the present study, a meta-analysis of multiple gene expression datasets with clinical data revealed that GRHL2 expression was increased in lung cancer compared with that in the normal tissues. Copy number analysis of , performed using datasets of whole exome sequencing involving 151 lung cancer cell lines, revealed frequent amplifications, suggesting that the increased expression may have resulted from gene amplification. A survival meta-analysis of using The Cancer Genome Atlas (TCGA) dataset showed no association of expression with overall survival. expression was found to be associated with EMT status in lung cancer in TCGA dataset and lung cancer cell lines. knockdown induced partial EMT in the /-immortalized normal lung epithelial cell line HBEC4KT without affecting proliferation measured by CCK-8 assays. In addition, silencing caused three lung cancer cell lines, H1975, H2009 and H441, to undergo partial EMT. However, the proliferative effects differed significantly. silencing promoted proliferation but not colony formation in H1975 cells whilst suppressing colony formation without affecting proliferation in H2009 cells, but it did not affect proliferation in H441 cells. These results suggest cell type-dependent effects of knockdown. Downstream, silencing enhanced the phosphorylation of AKT and ERK, assessed by western blotting with phospho-specific antibodies, in HBEC4KT, H1975 and H2009 cell lines but not in the H441 cell line. By contrast, transient overexpression did not affect A549 cell proliferation, which lack detectable endogenous expression of the GRHL2 protein. However, GRHL2 overexpression did suppress E-cadherin expression in A549 cells. These results suggested that does not only function as a tumor suppressor of EMT but can also behave as an oncogene depending on the lung cancer cell-type context.
颗粒头样蛋白2（GRHL2）是一种抑制上皮-间质转化（EMT）的转录因子。先前研究表明，GRHL2在包括乳腺癌、胰腺癌和结直肠癌在内的人类癌症中兼具致癌和抑癌作用。然而，其在肺癌中的作用仍不明确。在本研究中，一项对多个基因表达数据集与临床数据的荟萃分析显示，与正常组织相比，GRHL2在肺癌中的表达增加。使用涉及151个肺癌细胞系的全外显子测序数据集进行的拷贝数分析显示，GRHL2频繁扩增，提示其表达增加可能是基因扩增所致。使用癌症基因组图谱（TCGA）数据集对GRHL2进行的生存荟萃分析表明，GRHL2表达与总生存期无关。在TCGA数据集和肺癌细胞系中发现，GRHL2表达与肺癌中的EMT状态相关。在GRHL2基因敲除的GRHL2 +/+永生化正常肺上皮细胞系HBEC4KT中诱导了部分EMT，但通过CCK-8检测未影响其增殖。此外，GRHL2沉默导致三种肺癌细胞系H1975、H2009和H441发生部分EMT。然而，增殖效应差异显著。GRHL2沉默促进了H1975细胞的增殖，但不影响其集落形成，而在H2009细胞中抑制了集落形成但不影响增殖，但对H441细胞的增殖没有影响。这些结果表明GRHL2基因敲除具有细胞类型依赖性效应。在下游，通过使用磷酸化特异性抗体进行蛋白质印迹分析评估，GRHL2沉默增强了HBEC4KT、H1975和H2009细胞系中AKT和ERK的磷酸化，但在H441细胞系中未增强。相比之下，瞬时GRHL2过表达不影响A549细胞增殖，A549细胞缺乏可检测到的内源性GRHL2蛋白表达。然而，GRHL2过表达确实抑制了A549细胞中E-钙黏蛋白的表达。这些结果表明，GRHL2不仅作为EMT的肿瘤抑制因子发挥作用，还可根据肺癌细胞类型背景表现为癌基因。
