Summary Emerging studies have demonstrated the link between RNA modifications and various cancers, while the predictive value and functional mechanisms of RNA modification-related genes (RMGs) in esophageal squamous cell carcinoma (ESCC) remain unclear. Here we established a prognostic signature for ESCC based on five RMGs. The analysis of ESCC clinical samples further verified the prognostic power of the prognostic signature. Moreover, we found that the knockdown of NSUN6 promotes ESCC progression in vitro and in vivo , whereas the overexpression of NSUN6 inhibits the malignant phenotype of ESCC cells. Mechanically, NSUN6 mediated tRNA m 5 C modifications selectively enhance the translation efficiency of CDH1 mRNA in a codon dependent manner. Rescue assays revealed that E-cadherin is an essential downstream target that mediates NSUN6’s function in the regulation of ESCC progression. These findings offer additional insights into the link between ESCC and RMGs, as well as provide potential strategies for ESCC management and therapy.
Cui Zhai,Wei Feng,Wenhua Shi,Jian Wang,Qianqian Zhang,Xin Yan,Qingting Wang,Shaojun Li,Lu Liu,Yilin Pan,Yanting Zhu,Limin Chai,Cong Li,Pengtao Liu,Yuqian Chen,Manxiang Li
It has been shown that sphingosine-1-phosphate (S1P) is elevated in patients with pulmonary arterial hypertension (PAH) and promotes the proliferation of pulmonary artery smooth muscle cells (PASMCs). Meanwhile, S1P has been found to induce the activation of autophagy in several types of human diseases including cancers. However, it is still unclear whether activation of autophagy mediates S1P-induced PASMCs proliferation, and detailed mechanisms responsible for these processes are indefinite. The aims of this study are to address these issues. S1P dose- and time-dependently reduced the expression of E-cadherin/CDH1 and stimulated PASMCs proliferation; this was accompanied with the elevation of TNF receptor-associated factor 2 (TRAF2), up-regulation and ubiquitination of BECN1 and the activation of autophagy. Prior silencing TRAF2 or BECN1 using siRNA or pre-incubation of cells with autophagy inhibitor chloroquine phosphate (CQ) suppressed S1P-induced autophagy activation and subsequent CDH1 degradation and further PASMCs proliferation. Taken together, our study indicates that S1P promotes the activation of autophagy by accelerating TRAF2-mediated BECN1 up-regulation and ubiquitination, which in turn results in CDH1 reduction and contributes to PASMCs proliferation.
Sertoli cell-only syndrome (SCOS) is one of the most severe non-obstructive azoospermia (NOA) types, since only Sertoli cells with not any male germ cells exist with the seminiferous tubules. As such, it is of particular significance to elucidate molecular mechanisms underlying SCOS for improving the diagnosis and treatment strategies for this disease. Due to the difficulties in obtaining sufficient human testicular tissues and the limited availability of human cells, the traditional proteomics is inadequate for comparing the differences in large scale of protein expression patterns of human Sertoli cells between SCOS and normal men. To solve this issue on the requirement of large amount of cell numbers, we employed micro-proteomics to reveal distinct global protein expression profiles of human Sertoli cells between SCOS and obstructive azoospermia (OA) with normal spermatogenesis utilizing single human Sertoli cells. We found a significant downregulation of proteins involved in cell adhesion pathways in SCOS Sertoli cells, whereas proteins related to apoptosis were markedly upregulated. Interestingly, we identified the lower expression of SPARC (secreted protein acidic and rich in cysteine) and the higher expression of FGF2 (fibroblast growth factor 2) in human Sertoli cells of the SCOS compared to normal men. SPARC silencing led to upregulation of FGF2 in human Sertoli cells, and SPARC may be associated with the occurrence of SCOS and serves as a reliable marker for the diagnosis of this disease. This study thus comprehensively offers the proteomic landscape of human Sertoli cells in the testes of SCOS patients and it sheds a novel insight into the pathogenesis of SCOS.