Feigelman Gabriele, Simanovich Elina, Brockmeyer Phillipp, Rahat Michal A
Immunotherapy Laboratory, Carmel Medical Center, Haifa 3436212, Israel.
Ruth and Bruce Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa 3109601, Israel.
Biomedicines. 2023 Mar 2;11(3):768. doi: 10.3390/biomedicines11030768.
Metastasis in colorectal cancer is responsible for most of the cancer-related deaths. For metastasis to occur, tumor cells must first undergo the epithelial-to-mesenchymal transition (EMT), which is driven by the transcription factors (EMT-TFs) Snail, Slug twist1, or Zeb1, to promote their migration. In the distant organs, tumor cells may become dormant for years, until signals from their microenvironment trigger and promote their outgrowth. Here we asked whether CD147/EMMPRIN controls entry and exit from dormancy in the aggressive and proliferative (i.e., non-dormant) CT26 mouse colon carcinoma cells, in its wild-type form (CT26-WT cells). To this end, we knocked down EMMPRIN expression in CT26 cells (CT26-KD), and compared their EMT and cellular dormancy status (e.g., proliferation, pERK/pP38 ratio, vimentin expression, expression of EMT-TFs and dormancy markers), and angiogenic dormancy (e.g., VEGF and MMP-9 secretion, healing of the wounded bEND3 mouse endothelial cells), to the parental cells (CT26-WT). We show that knocking-down EMMPRIN expression reduced the pERK/pP38 ratio, enhanced the expression of vimentin, the EMT-TFs and the dormancy markers, and reduced the proliferation and angiogenic potential, cumulatively indicating that cells were pushed towards dormancy. When macrophages were co-cultured with both types of CT26 cells, the CT26-WT cells increased their angiogenic potential, but did not change their proliferation, state of EMT, or dormancy, whereas the CT26-KD cells exhibited values mostly similar to those of the co-cultured CT26-WT cells. Addition of recombinant TGFβ or EMMPRIN that simulated the presence of macrophages yielded similar results. Combinations of low concentrations of TGFβ and EMMPRIN had a minimal additive effect only in the CT26-KD cells, suggesting that they work along the same signaling pathway. We conclude that EMMPRIN is important as a gatekeeper that prevents cells from entering a dormant state, and that macrophages can promote an exit from dormancy.
结直肠癌转移是大多数癌症相关死亡的原因。为了发生转移，肿瘤细胞必须首先经历上皮-间质转化（EMT），这由转录因子（EMT-TFs）Snail、Slug twist1或Zeb1驱动，以促进其迁移。在远处器官中，肿瘤细胞可能会休眠数年，直到其微环境中的信号触发并促进其生长。在这里，我们研究了CD147/EMMPRIN是否控制侵袭性和增殖性（即非休眠）CT26小鼠结肠癌细胞（野生型形式，CT26-WT细胞）进入和脱离休眠状态。为此，我们敲低了CT26细胞（CT26-KD）中EMMPRIN的表达，并将它们的EMT和细胞休眠状态（例如增殖、pERK/pP38比值、波形蛋白表达、EMT-TFs和休眠标记物的表达）以及血管生成休眠（例如VEGF和MMP-9分泌、受伤的bEND3小鼠内皮细胞的愈合情况）与亲代细胞（CT26-WT）进行比较。我们发现，敲低EMMPRIN表达会降低pERK/pP38比值，增强波形蛋白、EMT-TFs和休眠标记物的表达，并降低增殖和血管生成潜力，累积表明细胞被推向休眠状态。当巨噬细胞与两种类型的CT26细胞共培养时，CT26-WT细胞增加了其血管生成潜力，但未改变其增殖、EMT状态或休眠状态，而CT26-KD细胞表现出的值大多与共培养的CT26-WT细胞相似。添加模拟巨噬细胞存在的重组TGFβ或EMMPRIN产生了类似的结果。低浓度TGFβ和EMMPRIN的组合仅在CT26-KD细胞中具有最小的累加效应，表明它们沿着相同的信号通路起作用。我们得出结论，EMMPRIN作为阻止细胞进入休眠状态的守门人很重要，并且巨噬细胞可以促进脱离休眠状态。
