Verbascoside inhibits oral squamous cell carcinoma cell proliferation, migration, and invasion by the methyltransferase 3-mediated microRNA-31-5p/homeodomain interacting protein kinase 2 axis.

The study aimed to investigate the effects of verbascoside on oral squamous cell carcinoma (OSCC) cellular behaviors and underlying molecular mechanisms. For this purpose, SCC9 and UM1 cell lines were treated with verbascoside, and their biological behaviors, including proliferation, migration, and invasion, were evaluated using cell counting kit-8, 5-Ethynyl-2'-deoxyuridine, and Transwell assays. The expression of methyltransferase-3 (METTL3), microRNA (miR)- 31-5p, and homeodomain interacting protein kinase-2 (HIPK2) were examined using quantitative real-time polymerase chain reaction (qRT-PCR). The interaction between METTL3 and miR-31-5p was evaluated by RNA immunoprecipitation and methylated RNA immunoprecipitation, while the interaction between miR-31-5p and HIPK2 was evaluated by dual-luciferase reporter analysis. The results indicated inhibition of OSCC cell proliferation, migration, and invasion post verbascoside treatment. Similarly, METTL3 was upregulated in OSCC cells and was inhibited post-verbascoside treatment. Overexpressing METTL3 promoted the cellular processes. Moreover, miR-31-5p was upregulated in OSCC cells, where METTL3 facilitated the processing of miR-31-5p in an N6-methyladenosine (m6A)-dependent manner. The HIPK2 served as miR-31-5p target, where overexpressing miR-31-5p or HIPK2 knockdown reversed the suppression of verbascoside-induced biological behaviors. Verbascoside inhibited the progression of OSCC by inhibiting the METTL3-regulated miR-31-5p/HIPK2 axis. These findings suggested that verbascoside might be an effective drug for OSCC therapy.

Huang Y ，Wu W ，Zhang X 《-》

METTL3-Mediated Maturation of miR-99a-5p Promotes Cell Migration and Invasion in Oral Squamous Cell Carcinoma by Targeting ZBTB7A.

METTL3 is an important methyltransferase in N(6)-methyladenosine (m6A) modification. Recently, METTL3 mediates methylation of pri-microRNA (miRNA) to accelerate miRNA maturation, regulating tumor development. This study explored whether METTL3 mediated miR-99a-5p to influence oral squamous cell carcinoma (OSCC) cell metastasis. MiR-99a-5p, ZBTB7A, and MATTL3 expression was measured using quantitative real-time PCR. Biological behaviors were assessed using cell counting kit-8, flow cytometry, Transwell assay, as well as western blot. Luciferase reporter assay evaluated the interaction between miR-99a-5p and ZBTB7A. METTL3-regulated pri-miR-99a-5p processing was determined by RNA binding protein immunoprecipitation (RIP) and methylated RNA immunoprecipitation (MeRIP) assays. The consequences clarified that miR-99a-5p was upregulated in OSCC cells. Downregulation of miR-99a-5p suppressed cellular viability, migration, invasion, and epithelial-mesenchymal transition (EMT), and induced apoptosis. ZBTB7A acted as a miR-99a-5p target and reversed the effects on cellular behaviors induced by miR-99a-5p inhibitor. m6A content and METTL3 expression were increased in OSCC cells. METTL3 promoted the m6A modification of pri-miR-99a-5p and thereby facilitated miR-99a-5p processing. Moreover, knockdown of METTL3 inhibited OSCC metastasis by downregulating miR-99a-5p. Taken together, METTL3 promoted miR-99a-5p maturation in an m6A-dependent manner, which further targets ZBTB7A to accelerate the progression of OSCC. These findings suggest potential targets for OSCC therapy.

Huang Y ，Guan Y ，Zhang X 《-》

Knockdown of circ_0011946 targets miR-216a-5p/BCL2L2 axis to regulate proliferation, migration, invasion and apoptosis of oral squamous cell carcinoma cells.

Circular RNAs (circRNAs) are implicated in the development of oral squamous cell carcinoma (OSCC). The aim of current research is to elucidate the role and mechanism of circ_0011946 in the functional behaviors of OSCC cells. Circ_0011946, microRNA (miR)-216a-5p, B cell lymphoma-2-like 2 protein (BCL2L2) abundances were exposed by quantitative reverse transcription polymerase chain reaction (qRT-PCR) or western blot. Cell proliferation, migration, invasion and apoptosis were detected by MTT, colony formation assay, transwell, wound-healing and flow cytometry assays, respectively. Target correlation was tested by dual-luciferase reporter and RNA pull-down assays. An in vivo xenograft experiment was employed to investigate the function of circ_0011946 on tumor growth in vivo. Circ_0011946 and BCL2L2 levels were increased, while miR-216a-5p level was decreased in OSCC tissues and cells. Circ_0011946 knockdown impeded proliferation, migration, and invasion, but promoted apoptosis in OSCC cells. Circ_0011946 functioned as a sponge for miR-216a-5p, and BCL2L2 was targeted by miR-216a-5p. Besides, miR-216a-5p or BCL2L2 knockdown partly attenuated the inhibitory influences of circ_0011946 silence or miR-216a-5p overexpression on OSCC cell progression. Furthermore, circ_0011946 post-transcriptionally regulated BCL2L2 through sponging miR-216a-5p. Moreover, circ_0011946 knockdown constrained OSCC tumor growth in vivo. Circ_0011946 silence repressed OSCC cell proliferation, migration, and invasion, but promoted apoptosis through the regulation of the miR-216a-5p/BCL2L2 axis.

Zhou Y ，Zhang S ，Min Z ，Yu Z ，Zhang H ，Jiao J ... -  《BMC CANCER》

hsa_circ_0072387 Suppresses Proliferation, Metastasis, and Glycolysis of Oral Squamous Cell Carcinoma Cells by Downregulating miR-503-5p.

Han L ，Cheng J ，Li A 《-》

Exosomal miR-146b-5p derived from cancer-associated fibroblasts promotes progression of oral squamous cell carcinoma by downregulating HIPK3.

Cancer-associated fibroblasts (CAFs) are vital constituents of the tumor microenvironment (TME) and play a predominant role in oral squamous cell carcinoma (OSCC) progression. We aimed to investigate the effect and mechanism of exosomal miR-146b-5p derived from CAFs on the malignant biological behavior of OSCC. Illumina small RNA (sRNA) sequencing was conducted to determine the differential expression patterns of microRNAs (miRNAs) in exosomes derived from CAFs and normal fibroblasts (NFs). Transwell and cell counting kit-8 (CCK-8) assays and xenograft tumor models in nude mice were used to investigate the effect of CAF exosomes and miR-146b-p on the malignant biological behavior of OSCC. Reverse transcription quantitative real-time PCR (qRT-PCR), luciferase reporter, western blotting (WB) and immunohistochemistry assays were employed to investigate the underlying mechanisms involved in CAF exosomes that promote OSCC progression. We demonstrated that CAF-derived exosomes were taken up by OSCC cells and enhanced the proliferation, migration, and invasion ability of OSCC. Compared with NFs, the expression of miR-146b-5p was increased in exosomes and their parent CAFs. Further studies showed that the decreased expression of miR-146b-5p inhibited the proliferation, migration and invasion ability of OSCC cells in vitro and the growth of OSCC cells in vivo. Mechanistically, miR-146b-5p overexpression led to the suppression of HIKP3 by directly targeting the 3'-UTR of HIPK3, as confirmed by luciferase assay. Reciprocally, HIPK3 knockdown partially reversed the inhibitory effect of the miR-146b-5p inhibitor on the proliferation, migration, and invasion ability of OSCC cells and restored their malignant phenotype. Our results revealed that CAF-derived exosomes contained higher levels of miR-146b-5p than NFs, and miR-146b-5p overexpression in exosomes promoted the malignant phenotype of OSCC by targeting HIPK3. Therefore, inhibiting exosomal miR-146b-5p secretion may be a promising therapeutic modality for OSCC.

He L ，Guo J ，Fan Z ，Yang S ，Zhang C ，Cheng B ，Xia J ... -  《-》