Department of Anesthesiology, QingPu Branch of Zhongshan Hospital Affiliated to Fudan University, Shanghai, China.
The First People's Hospital of Taicang City, Taicang Affiliated Hospital of Soochow University, Suzhou, Jiangsu, China.
J Immunol Res. 2022 Jun 1;2022:9385820. doi: 10.1155/2022/9385820. eCollection 2022.
The development and progression of many cancers may be related to SALL4, the role and molecular mechanism of which are unclear in colon adenocarcinoma (COAD).
The SALL4 expression in adjacent normal mucosa tissues and carcinoma tissues of patients with COAD was detected through bioinformatic analysis based on TCGA database and immunohistochemistry. Single-cell analysis showed that the expression of SALL4 in normal tissue was noticeably low. GSEA analysis suggested that the SALL4 upregulated the GO and pathway of growth and cancer development and downregulated metabolization pathway. The relationship between lymph node metastasis, histological grading, clinical staging, and the expression of SALL4 in carcinoma tissues was analyzed. The upregulated or downregulated SALL4 expression of COAD cell lines was established. The influence of SALL4 on COAD cells invasion and proliferation was detected using plate cloning assay and Transwell. The expressions of EMT-related proteins E-cadherin, N-cadherin, vimentin, and Twist were detected by Western blot. The EMT phenotype was analyzed by immunofluorescence.
The study confirmed that the expression of SALL4 was upregulated in COAD and positively correlated with the degree of tumor differentiation, tumor staging, and metastasis. The overexpression of SALL4 was related to a poor prognosis, promoted the invasion and proliferation of colorectal cancer cells, and accelerated the occurrence of EMT, which was characterized by upregulation of Twist, vimentin, and N-cadherin expressions and downregulation of E-cadherin. The immunofluorescence staining confirmed the EMT phenotype. On the contrary, knocking out SALL4 gene reversed EMT, weakened cell proliferation and invasion, inhibited upregulation of Twist, vimentin, and N-cadherin expressions and downregulation of E-cadherin.
To sum up, TNM grading, histological grading, and lymphatic metastasis were significantly correlated with SALL4 in tumor tissues. SALL4 played a vital role in tumor proliferation, invasion, and tumor EMT and may be a novel target for COAD.
许多癌症的发生和发展可能与 SALL4 有关，但 SALL4 在结肠腺癌（COAD）中的作用和分子机制尚不清楚。
通过 TCGA 数据库的生物信息学分析和免疫组织化学检测 COAD 患者癌旁正常黏膜组织和癌组织中 SALL4 的表达。单细胞分析显示，正常组织中 SALL4 的表达明显较低。GSEA 分析表明，SALL4 上调了生长和癌症发展的 GO 和通路，下调了代谢通路。分析 SALL4 在癌组织中的表达与淋巴结转移、组织学分级、临床分期的关系。构建 COAD 细胞系 SALL4 的上调或下调表达。通过平板克隆实验和 Transwell 检测 SALL4 对 COAD 细胞侵袭和增殖的影响。通过 Western blot 检测 EMT 相关蛋白 E-cadherin、N-cadherin、vimentin 和 Twist 的表达。通过免疫荧光分析 EMT 表型。
本研究证实 SALL4 在 COAD 中表达上调，且与肿瘤分化程度、肿瘤分期和转移呈正相关。SALL4 的过表达与预后不良相关，促进结直肠癌细胞的侵袭和增殖，并加速 EMT 的发生，其特征是 Twist、vimentin 和 N-cadherin 的表达上调和 E-cadherin 的表达下调。免疫荧光染色证实了 EMT 表型。相反，敲除 SALL4 基因逆转了 EMT，减弱了细胞增殖和侵袭，抑制了 Twist、vimentin 和 N-cadherin 的表达上调和 E-cadherin 的表达下调。
综上所述，TNM 分级、组织学分级和淋巴转移与肿瘤组织中的 SALL4 显著相关。SALL4 在肿瘤增殖、侵袭和肿瘤 EMT 中发挥着重要作用，可能是 COAD 的一个新靶点。
