Downregulation of miR-221-3p promotes the ferroptosis in gastric cancer cells via upregulation of ATF3 to mediate the transcription inhibition of GPX4 and HRD1.

BACKGROUND: Gastric cancer (GC) is an aggressive gastrointestinal tumor. MiRNAs participate in the tumorigenesis of GC. Nevertheless, the function of miR-221-3p in GC remains largely unknown. METHODS: RNA levels were assessed by RT-qPCR. Western blot was performed to test the protein levels. The relation between miR-221-3p and ATF3 was investigated by dual-luciferase reporter assay. ChIP and dual-luciferase reporter assay were applied to assess the interaction between ATF3 and HRD1 or GPX4. Meanwhile, cell proliferation was investigated by CCK8 and colony formation assay. The content of erastin-induced Fe2+ was investigated by iron assay kit. Erastin-induced lipid ROS level was assessed by C11-BODIPY 581/591. Co-immunoprecipitation was used to detect the interaction between HRD1 and ACSL4. In addition, xenograft mice model was established to detect the effect of miR-221-3p in GC. RESULTS: Depletion of miR-221-3p greatly attenuated GC cell proliferation through promoting ferroptosis. Meanwhile, ATF3 was downregulated in GC, and it was identified to be the downstream mRNA of miR-221-3p. MiR-221-3p downregulation could promoted the ferroptosis in GC cells through upregulation of ATF3. HRD1 mediates ubiquitination and degradation of ACSL4 to inhibit ferroptosis. ATF3 upregulation could reduce GC cell proliferation via downregulating the transcription of GPX4 and HRD1. Furthermore, downregulation of miR-221-3p markedly attenuated the growth of GC in mice. CONCLUSION: HRD1 mediates ubiquitination and degradation of ACSL4 to inhibit ferroptosis. MiR-221-3p depletion upregulates the ferroptosis in GC cells via upregulation of ATF3 to mediate the transcription inhibition of GPX4 and HRD1. Our study might provide a novel target for GC treatment.

miR-1266-3p Suppresses Epithelial-Mesenchymal Transition in Colon Cancer by Targeting P4HA3.

Numerous studies have been conducted to demonstrate that miRNA is strongly related to colon cancer progression. Nevertheless, there are few studies regarding the function for miR-1266-3p in colon cancer, and the molecular mechanism remains poorly know. Our study was designed to examine the level of miR-1266-3p expression among the colon cancer tissue and cell and to study the role and regulatory mechanism for miR-1266-3p among colon cancer's malignant biologic behavior. First, we found that miR-1266-3p expression was distinctly lower in colonic carcinoma tissues and cells than in nontumor ones, and the prognosis of low miR-1266-3p patients was distinctly worse than that of high miR-1266-3p patients. Second, we predicted that the target gene of miR-1266-3p was prolyl 4-hydroxylase subunit alpha 3 (P4HA3) through bioinformatics, and the targeting relationship between the two was verified by a dual luciferase assay report. Furthermore, miR-1266-3p inhibited the growth and metastasis of colon cancer in vitro as well as in vivo, and this effect could be alleviated by overexpressing P4HA3. Even more importantly, our study demonstrated that miR-1266-3p inhibited epithelial-mesenchymal transition (EMT) by targeting P4HA3. In conclusion, miR-1266-3p could inhibit growth, metastasis, and EMT in colon cancer by targeting P4HA3. Our discoveries might offer a novel target for colon cancer diagnosis and treatment.

Prolyl 4-hydroxylase subunit alpha 3 facilitates human colon cancer growth and metastasis through the TGF-ß/Smad signaling pathway.

Prolyl 4-hydroxylase subunit alpha 3 (P4HA3) has been known to be associated with a variety of human cancers. However, the role of P4HA3 on colon cancer growth and metastasis is unclear. In this study, we investigated the effect of P4HA3 on the growth and metastasis of colon cancer and its possible molecular mechanism. First of all, we demonstrated that P4HA3 expression was greatly higher in cells and tissues of colon cancer than that in non-tumor tissues and cells, and the prognosis of patients who had higher P4HA3 was distinctively poorer than patients who had lower level of P4HA3. Second, it was shown that P4HA3 knockdown strongly inhibited the migration, proliferation and invasion ability of colon cancer cells. However, P4HA3 over-expression accelerated the abilities. Meanwhile, P4HA3 could promote subcutaneous tumorigenesis in nude mice in vivo. In addition, P4HA3 knockdown significantly decreased mesenchymal markers Vimentin, N-cadherin and Snail expression and increased epithelial marker E-cadherin expression. And conversely, over-expression of P4HA3 produced the opposite effects. In the current study, there was further evidence that down-regulating P4HA3 significantly reduced both TGF-ß and its following molecules including p-Smad2 as well as p-Smad3. However, overexpression of P4HA3 showed the opposite effect. In conclusion, this study shows that P4HA3 promotes the human colon cancer growth and metastasis by affecting TGF-ß/Smad signaling pathway. P4HA3 may become a new target for early diagnosis, treatment and prognosis assessment of colon cancer.

Identification of potential core genes in gastric cancer using bioinformatics analysis.

BACKGROUND: Gastric cancer is the third leading cause of cancer-related mortality in China. Most patients with gastric cancer have no obvious early symptoms; thus, many of them are in the middle and late stages of gastric cancer at first diagnosis and miss the best treatment opportunity. Molecular targeted therapy is particularly important in changing this status quo. METHODS: Three microarray datasets (GSE29272, GSE33651, and GSE54129) were selected from the Gene Expression Omnibus (GEO) database. Differentially expressed genes (DEGs) were screened using GEO2R. The Database for Annotation, Visualization and Integrated Discovery (DAVID) was used to analyze the functional features of these DEGs and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment. The protein-protein interaction (PPI) of these DEGs was visualized by Cytoscape software. The expressions of hub genes were evaluated based on Gene Expression Profiling Interactive Analysis (GEPIA). Moreover, we used the online Kaplan-Meier plotter survival analysis tool to evaluate the prognostic values of hub genes. The Target Scan database was used to predict microRNAs that could regulate the target gene, collagen type IV alpha 1 chain (COL4A1). The OncomiR database was used to analyze the expression levels of three microRNAs, as well as the relationships with tumor stage, grade, and prognosis. RESULTS: We identified 78 DEGs, including 53 upregulated genes and 25 downregulated genes. The DEGs were mainly enriched in extracellular matrix organization, extracellular structure organization, and response to wounding. Moreover, three KEGG pathways were markedly enriched, including focal adhesion, complement and coagulation cascades, and extracellular matrix (ECM)-receptor interaction. Among these 78 genes, we selected 10 hub genes. The overexpression levels of these hub genes were closely related to poor prognosis and the development of gastric cancer (except for COL3A1, LOX, and CXCL8). Moreover, we found that microRNA-29a-3p, miR-29b-3p, and miR-29c-3p were the potential microRNAs that could regulate the target gene, COL4A1. CONCLUSIONS: Our results showed that FN1, COL1A1, TIMP1, COL1A2, SPARC, COL4A1, and SERPINE1 could contribute to the development of novel molecular targets and biomarker-driven treatments for gastric cancer.

(4-Chlorobenzoyl)(4-chlorophenyl)amino 3-(2-nitrophenyl)propanoate.

In the title hydroxamic acid derivate, C22H16Cl2N2O5, the nitro-substituted benzene ring forms dihedral angles of 14.11 (15) and 16.08 (15)°, with the 4-chloro-benzoyl and 4-chloro-phenyl benzene rings, respectively. The dihedral angle between the chloro-substituted benzene rings is 2.28 (13)°. In the crystal, mol-ecules are linked by weak C-H⋯O hydrogen bonds, forming chains along [100].