Lung cancer, the leading cause of death worldwide, is associated with the highest morbidity. Non-small cell lung cancer (NSCLC) accounts for 80–85% of lung cancer cases. Advances in the domain of cancer treatment have improved the prognosis and quality of life of patients with metastatic NSCLC. Nevertheless, tumor progression or metastasis owing to treatment failure caused by primary or secondary drug resistance remains the cause of death in the majority of cases. Epithelial–mesenchymal transition (EMT), a vital biological process wherein epithelial cancer cells lose their inherent adhesion and transform into more invasive mesenchymal-like cells, acts as a powerful engine driving tumor metastasis. EMT can also induce immunosuppression in the tumor environment, thereby promoting cancer development and poor prognosis among patients with NSCLC. This review aims to elucidate the effect of EMT on metastasis and the tumor immune microenvironment. Furthermore, it explores the possible roles of EMT inhibition in improving the treatment efficacy of NSCLC. Targeting EMT may be an ideal mechanism to inhibit tumor growth and progression at multiple steps.
Purpose: Long non-coding RNA (lncRNA) SPRY4 intronic transcript 1 (SPRY4-IT1) is reported to play important roles in the occurrence and development of many tumors. However, the possible role of SPRY4-IT1 in cisplatin (DDP) resistance of non-small-cell lung cancer (NSCLC) remains unclear. The aim of this study is to investigate the functions and molecular mechanisms underlying SPRY4-IT1 of cisplatin resistance in NSCLC. Methods: Expression of SPRY4-IT1 was analyzed in A549 and cisplatin-resistant A549/DDP cell lines by quantitative real-time polymerase chain reaction (RT-qPCR). Overexpression techniques were applied to investigate the biological functions of SPRY4-IT1 in cisplatin-resistant A549/DDP cells. The effects of SPRY4-IT1 on proliferation and apoptosis were evaluated using cell counting kit-8 (CCK8) assays, colony formation assay and flow-cytometric analysis. The expressions of epithelial–mesenchymal transition (EMT)-associated proteins, including E-cadherin and Vimentin, were detected by Western blot. Microarray analysis was performed to identify the putative targets of SPRY4-IT1, which were further verified by Western blotting and RT-qPCR. A549/DDP cells transfected with pCDNA-SPRY4-IT1 were injected into nude mice in order to verify the effect of SPRY4-IT1 on cisplatin resistance in vivo. Results: The present study demonstrated that SPRY4-IT1 expression was decreased in A549/DDP cells compared with parental A549 cells. Upregulation of SPRY4-IT1 suppressed cell proliferation and caused apoptosis of A549/DDP cells both in vitro and in vivo. MPZL-1 was negatively regulated by SPRY4-IT1. Furthermore, upregulation of SPRY4-IT1 and downregulation of MPZL-1 could suppress epithelial–mesenchymal transition (EMT), which was characterized by increased E-cadherin expression and decreased Vimentin expression. Conclusion: Upregulation of SPRY4-IT1 reversed the cisplatin-resistant phenotype of NSCLC partially by downregulating MPZL-1 via inhibiting EMT process.
27 October 2022 in Journal of International Medical Research
With the extensive use of immune checkpoint inhibitors (ICI) in advanced-stage cancers, immune-related adverse events (irAEs) have been noted in various systems. While most irAEs are reversible and manageable, cardiac toxicities are rare but life-threatening, with high mortality rates. We present a case of a 71-year-old man with cholangiocarcinoma who developed myocarditis related to ICIs 29 days after the first infusion of teriprizumab combined with albumin-bound paclitaxel and gemcitabine. He was initially asymptomatic after admission but with substantial elevations of troponin I and myocardial enzymes. Sixteen hours after admission, he developed palpitations, dizziness, and syncope. Electrocardiography confirmed third-degree atrioventricular block and frequent ventricular premature contractions for which he received high-dose corticosteroids and a permanent pacemaker. The patient survived and permanently discontinued immunotherapy. Early identification and intervention are the keys to improving the prognosis of immune myocarditis.