Poirah Indrajit, Chakraborty Debashish, Dixit Pragyesh, Samal Supriya, Banerjee Smaran, Mukherjee Tathagata, Chattopadhyay Subhasis, Nath Gautam, Bhattacharyya Asima
School of Biological Sciences, National Institute of Science Education and Research (NISER) Bhubaneswar, An OCC of Homi Bhabha National Institute, Khurda, Odisha, India.
Department of Gastroenterology, Acharya Harihar Post Graduate Institute of Cancer, Cuttack, India.
Eur J Clin Invest. 2024 Dec;54 Suppl 2(Suppl 2):e14352. doi: 10.1111/eci.14352.
The hypoxic microenvironment is a key component of the gastric tumour niche. Carcinoembryonic antigen-related cell adhesion molecule 6 (CEACAM6) is upregulated in gastric cancer and is considered a novel biomarker for the disease. However, no prior studies have elaborated on the status of CEACAM6 and its role in the hypoxic gastric cancer niche.
In this short study, we evaluated the effect of hypoxia in modulating CEACAM6 level in gastric cancer cells (GCCs) through western blotting and determined the effect of CEACAM6 upregulation on gastric cancer progression through clonogenicity, cell proliferation and migration assays. The wound-healing ability of GCCs was downregulated by siRNA-mediated CEACAM6 silencing. Human gastric cancer biopsy samples were examined by immunofluorescence microscopy to assess the level of a hypoxia marker HIF1α and CEACAM6. The effect of empty vector or CEACAM6-expression on peripheral blood-derived mononuclear cell (PBMC)-derived macrophage polarization under normoxia or hypoxia was studied by incubating macrophages in conditioned medium collected from GCC cultures. Macrophage polarization status was observed using flow cytometry and fluorescence microscopy. Reactive oxygen species (ROS) generation by macrophages was evaluated using fluorescence microscopy.
We identified that hypoxia promoted CEACAM6 in GCCs, and these cells acquired increased proliferative potential and migration ability. Moreover, the cell culture supernatant from hypoxia-exposed CEACAM6-overexpressing cells promoted an M2-like macrophage population and discouraged the M1 phenotype.
This study established that hypoxia increased CEACAM6 which promoted gastric cancer progression by influencing GCC proliferation and motility as well as macrophage polarization.
缺氧微环境是胃肿瘤微环境的关键组成部分。癌胚抗原相关细胞黏附分子6（CEACAM6）在胃癌中上调，被认为是该疾病的一种新型生物标志物。然而，此前尚无研究阐述CEACAM6在缺氧胃癌微环境中的状态及其作用。
在这项简短的研究中，我们通过蛋白质印迹法评估了缺氧对胃癌细胞（GCCs）中CEACAM6水平的调节作用，并通过克隆形成、细胞增殖和迁移试验确定了CEACAM6上调对胃癌进展的影响。通过小干扰RNA介导的CEACAM6沉默下调了GCCs的伤口愈合能力。通过免疫荧光显微镜检查人胃癌活检样本，以评估缺氧标志物缺氧诱导因子1α（HIF1α）和CEACAM6的水平。通过在从GCC培养物收集的条件培养基中培养巨噬细胞，研究了空载载体或CEACAM6表达对常氧或缺氧条件下外周血来源单核细胞（PBMC）衍生巨噬细胞极化的影响。使用流式细胞术和荧光显微镜观察巨噬细胞极化状态。使用荧光显微镜评估巨噬细胞产生的活性氧（ROS）。
我们发现缺氧促进了GCCs中CEACAM6的表达，并且这些细胞获得了增强的增殖潜力和迁移能力。此外，来自缺氧暴露的CEACAM6过表达细胞的细胞培养上清液促进了M2样巨噬细胞群体的形成，并抑制了M1表型。
本研究证实缺氧增加了CEACAM6的表达，其通过影响GCC的增殖、运动能力以及巨噬细胞极化促进了胃癌进展。
