Protein tyrosine phosphatase MEG2 (MEG2/PTPN9), a classic tyrosine-specific protein tyrosine phosphatase (PTP), is involved in the progression of liver, breast, and gastric cancers. However, the function and regulation of MEG2 in colorectal cancer (CRC) still remain unclear. In this study, we investigated the expression of MEG2 in CRC and found that MEG2 was downregulated in human CRC tissues compared to normal corresponding tissues. Moreover, in vivo and in vitro assays revealed that MEG2 plays a vital role in CRC cell proliferation, invasion, and apoptosis. In addition, mechanism analysis validated miR-21 as a direct regulator of MEG2, and miR-21 plays a critical role in promoting proliferation, invasion, and suppression of apoptosis in CRC by targeting MEG2. Taken together, this study demonstrates the significant role for miR-21 in regulating MEG2 in CRC and may represent a potential target for CRC therapy.

中文翻译：

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miR-21-MEG2 轴在结直肠癌中的关键作用

蛋白酪氨酸磷酸酶 MEG2 (MEG2/PTPN9) 是一种经典的酪氨酸特异性蛋白酪氨酸磷酸酶 (PTP)，参与肝癌、乳腺癌和胃癌的进展。然而，MEG2 在结直肠癌 (CRC) 中的功能和调节仍不清楚。在本研究中，我们研究了 MEG2 在 CRC 中的表达，发现与正常相应组织相比，MEG2 在人 CRC 组织中表达下调。此外，在体内和体外分析表明，MEG2 在 CRC 细胞增殖、侵袭和凋亡中起着至关重要的作用。此外，机制分析证实 miR-21 是 MEG2 的直接调节因子，miR-21 通过靶向 MEG2 在促进 CRC 增殖、侵袭和抑制细胞凋亡中发挥关键作用。总之，这项研究证明了 miR-21 在调节 CRC 中 MEG2 中的重要作用，并且可能代表了 CRC 治疗的潜在靶点。