MiR-155-5p promotes oral cancer progression by targeting chromatin remodeling gene ARID2.

Dysregulation of miRNAs is associated with aberrant migration and invasion by suppressing relevant target genes in multiple cancers, including oral squamous cell carcinoma (OSCC). Accumulating evidence suggests that microRNA-155-5p is involved in carcinogenesis and tumor progression. However, the exact function and molecular mechanism of miR-155-5p in OSCC remain unclear. This study aimed to investigate the function of miR-155-5p and the molecular mechanisms underlying the influencing progression of OSCC. The miR-155-5p expression level in the OSCC tissues and oral cancer cell lines were determined by the qRT-PCR. Gain-of-function and knockdown approach were used to examine the effect of miR-155-5p on cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of OSCC. The luciferase reporter assay was applied to confirm the AT-rich interactive domain 2 (ARID2) as a potential target of miR-155-5p, and the rescue experiment was employed to verify the roles of the miRNA-155-5p-ARID2 axis in OSCC progression. Immunohistochemical staining was used to detect ARID2 expression in another cohort sample tissues from OSCC patients. MiR-155-5p was significantly upregulated in OSCC tissues and cell lines. The miR-155-5p expression level was positively correlated with tumor size, TNM stage, histological grade and lymph node metastasis of OSCC patients. Functional assays demonstrated that miR-155-5p enhanced OSCC cell proliferation, migration and invasion. Mechanistically, ARID2 was identified as a direct target and functional effector of miR-155-5p in OSCC. Furthermore, ARID2 overexpression could rescue the aberrant biological function by overexpressed miR-155-5p in OSCC cells. Notably, we showed that ARID2 could be used as an independent prognosis factor in OSCC. Our results suggest that miR-155-5p facilitates tumor progression of OSCC by targeting ARID2, and miR-155-5p-ARID2 axis may be a potential therapeutic target of OSCC.

Wu M ，Duan Q ，Liu X ，Zhang P ，Fu Y ，Zhang Z ，Liu L ，Cheng J ，Jiang H ... -  《-》

LncRNA PVT1 promotes malignant progression by regulating the miR-7-5p/CDKL1 axis in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC), one of the most common types of head and neck squamous cell carcinoma (HNSCC), is characterized by high incidence and mortality. PVT1 is a long non-coding RNA (lncRNA) that plays an oncogenic role in various cancer types. This study aims to reveal the role and underlying molecular mechanism of PVT1 in OSCC progression. The expression levels of PVT1, miR-7-5p, and CDKL1 mRNA were evaluated using qRT-PCR. Western blot and IHC analysis were conducted to determine the protein expression of CDKL1. The biological functions of PVT1, miR-7-5p, and CDKL1 in OSCC were investigated through CCK-8, transwell migration and invasion assays. In vivo experiments utilized a xenograft model to examine the impact of PVT1 on OSCC. Furthermore, the interaction among PVT1, miR-7-5p, and CDKL1 was explored using RNA pull down assay and luciferase reporter assays. We found that PVT1 enhanced cell proliferation, migration, and invasion by targeting CDKL1. In addition, PVT1 functions as a sponge to modulate miR-7-5p, thereby influencing the expression of CDKL1 and the progression of OSCC. In conclusion, this study illustrates that the "PVT1/miR-7-5p/CDKL1" pathway is capable of promoting the progression of OSCC and may serve as a promising target for developing treatment strategies for OSCC.

Li J ，Ding S ，Li M ，Zou B ，Chu M ，Gu G ，Chen C ，Liu YJ ，Zheng K ，Meng Z ... -  《-》

RUNX1/miR-429 feedback loop promotes growth, metastasis, and epithelial-mesenchymal transition in oral squamous cell carcinoma by targeting ITGB1.

This study aimed to explore the role of miR-429 on the progression of oral squamous cell carcinoma (OSCC). OSCC cell lines were transfected with miR-429 mimic, pcDNA3.1-RUNX1, or pcDNA3.1-ITGB1, and their cell viability, apoptosis, migration, and invasion abilities were analyzed by cell counting, terminal deoxynucleotidyl transferase dUTP nick-end labeling staining, wound healing, and transwell assays, respectively. Furthermore, luciferase reporter assay, RNA pull-down, and ChIP were used to assess the regulation of miR-429, RUNX1, and ITGB1 expression in OSCC. Lastly, the biological role of the RUNX1/miR-429 feedback loop was explored in nude mice. The results revealed that miR-429 level was down-regulated, while RUNX1 and ITGB1 levels were up-regulated in OSCC tissues and that miR-429 was negatively correlated with RUNX1 and ITGB1 in OSCC tissues. Transfection of miR-429 mimic suppressed OSCC cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT). Moreover, we found that miR-429 participated in OSCC progression by directly targeting ITGB1. Additionally, we found that RUNX1 negatively regulated miR-429 expression by binding to its promoter. Our results also revealed that the RUNX1/miR-429 feedback loop regulated ITGB1 expression and that RUNX1 overexpression rescued the inhibitory effects of miR-429 mimic on OSCC cells. In addition, miR-429 mimic significantly suppressed tumor growth, inflammatory cell infiltration, EMT, and ITGB1 expression in vivo, which were inhibited by RUNX1 overexpression. Altogether, these results indicate that the RUNX1/miR-429 feedback loop promoted growth, metastasis, and EMT in OSCC by targeting ITGB1.

Lu X ，Yang Y ，Chen J ，Zhao T ，Zhao X ... -  《-》

miR-9-5p/HMMR regulates the tumorigenesis and progression of clear cell renal cell carcinoma through EMT and JAK1/STAT1 signaling pathway.

The most common malignant type of kidney cancer is clear cell renal cell carcinoma (ccRCC). The expression levels of hyaluronan-mediated motility receptor (HMMR) in many tumor types are significantly elevated. HMMR is closely associated with tumor-related progression, treatment resistance, and poor prognosis, and has yet to be fully investigated in terms of its expression patterns and molecular mechanisms of action in ccRCC. Further research is imperative to elucidate these aspects. We used The Cancer Genome Atlas (TCGA) database to preliminarily investigate HMMR expression and function in ccRCC and the data for 19 samples from the NCBI GEO database (GSE207493) for single-cell analysis. We assessed the differential expression level of HMMR between ccRCC cancerous tissues and their matched non-tumor tissues. Subsequently, a series of in vivo and in vitro experiments were designed to elucidate the biological function of HMMR in ccRCC, including Transwell assays, CCK-8 assays, clone formation assays and subcutaneous xenograft experiments in nude mice. Through bioinformatics analysis, we identified potential microRNAs (miRNAs) that may regulate HMMR, as well as the possible signaling pathways involved. Finally, we conducted a series of cellular functional experiments to validate our hypotheses regarding the HMMR axis. HMMR expression was significantly up-regulated in tumor tissues of ccRCC patients, and elevated HMMR expression level showed a strong correlation with ccRCC progression and adverse prognoses of patients. Knocking down HMMR inhibited the proliferative and migratory abilities of ccRCC cells, while its overexpression amplified these oncogenic properties. In nude mice model, reduced HMMR expression inhibited ccRCC tumor proliferation in vivo. Furthermore, overexpression of an upstream transcriptional regulator, miR-9-5p, effectively downregulated HMMR expression and thus impeded ccRCC cells proliferation and migration. HMMR might influence ccRCC growth via the Epithelial-Mesenchymal Transition (EMT) pathway and the Janus Kinase 1/Signal Transducer and Activator of Transcription 1 (JAK1/STAT1) pathway. HMMR is overexpressed in ccRCC, and there is a significant link between high HMMR expression and tumor progression, as well as poor patient prognosis. Specifically, HMMR could be targeted and inhibited by miR-9-5p and might modulate the tumorigenesis and progression of ccRCC through both EMT and JAK1/STAT1 signaling pathway.

Niu X ，Lu D ，Zhan W ，Sun J ，Li Y ，Shi Y ，Yu K ，Huang S ，Ma X ，Liu X ，Liu B ... -  《Journal of Translational Medicine》

MALAT1 promotes epithelial-mesenchymal transition of pancreatic cancer cells through the miR-141-5p-TGF-ß-TGFBR1/TGFBR2 axis.

Li Z ，Yue C ，Hou S ，Huang X ，Wang Z ，Hu W ，Lu H ... -  《-》