LUCAT1 as an oncogene in tongue squamous cell carcinoma by targeting miR-375 expression

Emerging studies suggested that lncRNAs play a crucial molecular role in cancer development and progression. LncRNA LUCAT1 has been proved as oncogenic molecular in lung cancer, glioma, osteosarcoma, renal carcinoma and oesophageal squamous cell carcinoma. However, its roles and function mechanisms in tongue squamous cell carcinoma (TSCC) are still unknown. We showed that the expression of LUCAT1 was up-regulated in the TSCC cells and tissues and the higher LUCAT1 expression was associated with the poor overall survival (OS). Knockdown expression of LUCAT1 suppressed TSCC cell proliferation, cycle and migration. In addition, we demonstrated that miR-375 overexpression inhibited the luciferase activity of LUCAT1 wild-type and knockdown LUCAT1 promoted the miR-375 expression in TSCC cell. Furthermore, we indicated that miR-375 expression was down-regulated in the TSCC cell lines and tissues and the lower expression of miR-375 was associated with poor OS. The expression of miR-375 was inversely correlated with LUCAT1 expression in the TSCC tissues. Knockdown LUCAT1 promoted TSCC cell proliferation, cell cycle and migration partly through regulating miR-375 expression. In summary, this study suggested the tumorigenic effect of lncRNA LUCAT1 in TSCC cells by targeting miR-375 expression.     

LINC01783 accelerated tongue squamous cell carcinoma progression via inhibiting miR-199b-5p

Growing studies illustrated that lncRNAs exert critical roles in development and occurrence of tumours including TSCC. In this research, we indicated that LINC01783 was up-regulated in TSCC cells (SCC1, Cal27, UM1 and SCC4) when compared to NHOK cell. RT-qPCR analysis indicated that LINC01783 was overexpressed in 22 TSCC cases (73.3%, 22/30) compared with no-tumour specimens. LINC01783 level was up-regulated in TSCC specimens when compared to no-tumour specimens. Ectopic expression of LINC01783 promoted TSCC cell cycle and growth and EMT progression in both TSCC cell SCC1 and Cal27. Overexpression of LINC01783 sponged miR-199b-5p in TSCC cell and elevated expression of LINC01783 inhibited miR-199b-5p expression. Moreover, we illustrated that miR-199b-5p was down-regulated in TSCC cells and specimen and LINC01783 level was up-regulated in TSCC specimens when compared to no-tumour specimens. Elevated expression of LINC01783 promoted TSCC cell growth, cycle and EMT progression by sponging miR-199b-5p. These data suggested that LINC01783 functioned as one oncogene and might be one treatment target for TSCC.     

miR-19a and miR-424 target TGFBR3 to promote epithelial-to-mesenchymal transition and migration of tongue squamous cell carcinoma cells

Previous studies indicate that TGFBR3 (transforming growth factor type III receptor, also known as betaglycan), a novel suppressor of progression in certain cancers, is down-regulated in tongue squamous cell carcinoma (TSCC). However, the role of this factor as an upstream regulator in TSCC cells remains to be elucidated. The present study was designed to elucidate whether TGFBR3 gene expression is regulated by two microRNA molecules, miR-19a and miR-424. The study also aimed to determine if these microRNAs promote migration of CAL-27 human oral squamous cells. Immunohistochemistry (IHC) and western blot analyses demonstrated that TGFBR3 protein levels were dramatically down-regulated in clinical TSCC specimens. Conversely, bioinformatics analyses and qRT-PCR results confirmed that both miR-19a and miR-424 were markedly up-regulated in clinical TSCC specimens. In this study, we observed that transfection of a TGFBR3-containing plasmid dramatically inhibited epithelial-to-mesenchymal transition (EMT) and migration in CAL-27 cells. Co-immunoprecipitation analyses also revealed that TGFBR3 forms a complex with the β-arrestin 2 scaffolding protein and IκBα. Furthermore, overexpression of TGFBR3 decreased p-p65 expression and increased IκBα expression; these effects were subsequently abolished following knockdown of β-arrestin 2. Moreover, over-expression of miR-19a and miR-424 promoted migration and EMT in CAL-27 cells. We also observed that the promotion of EMT by miR-19a and miR-424 was mediated by the inhibition of TGFBR3. Our study provides evidence that miR-19a and miR-424 play important roles in the development of TSCC. These results expand our understanding of TGFBR3 gene expression and regulatory mechanisms pertaining to miRNAs.     

miR-214通过调控Notch1信号对口咽鳞状细胞癌细胞株增殖、侵袭及凋亡的作用机制研究

目的研究miR-214通过调控Notch1信号对口咽鳞状细胞癌（OSCC）细胞株增殖、侵袭及凋亡的作用机制。 方法在ATCC细胞库购买OSCC细胞株,分为3组：抑制组（IN组）、模拟组（SI组）及对照组（CO组）。通过Western blot法、qRT-PCR法、TUNEL法、侵袭实验及CCK-8法分析3组癌细胞中Notch1的蛋白、mRNA表达水平、细胞凋亡、迁移及增殖能力的差异性,三组间比较采用单因素方差分析,组间两两比较采用LSD-t检验。 结果IN、SI、CO组细胞内miR-214mRNA表达量分别为1.15±0.26,3.34±0.89,2.08±0.67,SI组分别与IN组、CO组比较,差异具有统计学意义（t = 5.281,P = 0.002;t = 2.529,P = 0.045）;SI组、IN组的Notch1-UTR表达分别为0.42±0.11、0.86±0.09,差异具有统计学意义（t = 5.362,P = 0.006）;IN、SI、CO组的OSCC细胞凋亡率分别为（0.78±0.10）﹪、（0.32±0.06）﹪、（0.56±0.12）﹪,IN组分别与CO组、SI组比较,差异具有统计学意义（t = 3.149,P = 0.020;t = 8.823,P < 0.001）;IN、SI、CO组癌细胞的增殖率分别为（0.65±0.05）﹪、（1.26±0.06）﹪、（1.89±0.04）﹪,IN组与SI组、IN组与CO组比较,差异具有统计学意义（t = 11.056,P < 0.001;t = 27.394,P < 0.001）,CO组与SI组比较,差异具有统计学意义（t = 12.365,P < 0.001）;IN、SI、CO组癌细胞侵袭率分别为（0.13±0.02）﹪、（0.89±0.13）﹪、（0.48±0.11）﹪,SI组与CO组、SI组与IN组比较,差异具有统计学意义（t = 4.176,P = 0.006;t = 10.147,P < 0.001）;IN、SI、CO组的Notch1蛋白含量分别为：2.38±1.34、0.94±0.23、1.76±0.67,SI组与CO组、SI组与IN组比较,差异具有统计学意义（t = 2.588,P = 0.041;t = 2.368,P = 0.056）;IN、SI、CO组的Notch1 mRNA表达量分别为4.26±1.06、1.45±0.38、2.46±0.87,IN组与CO组、IN组与SI组比较,差异具有统计学意义（t = 2.935,P = 0.026;t = 5.583,P = 0.001）。 结论miR-214可能与OSCC细胞株增殖呈负相关,在细胞中miR-214含量升高,可能抑制Notch1信号通路表达,从而促进癌细胞增长、侵袭,抑制癌细胞凋亡。     

CircTIMELESS regulates the proliferation and invasion of lung squamous cell carcinoma cells via the miR-136-5p/ROCK1 axis

Numerous studies demonstrate that circular RNAs (circRNAs) are critical regulators of the occurrence and progression of tumors. However, research on the involvement of circRNAs in lung squamous cell carcinoma (LUSC) is limited. In our study, circTIMELESS (also named hsa_circ_0000408 in the Human circRNA Database) was upregulated in both LUSC tissues and LUSC cells, and circTIMELESS expression was positively associated with the TNM stage. Moreover, circTIMELESS silencing markedly suppressed invasion in vitro and disrupted proliferation in vitro as well as in vivo. Additional investigations have shown that circTIMELESS functions as a miR-136-5p “sponge” and regulates miR-136-5p expression. Furthermore, the impact of miR-136-5p upregulation was consistent with the results of circTIMELESS silencing, both of which inhibited the proliferation and invasion of LUSC cells. Additional results showed that Rho-associated coiled-coil containing protein kinase 1 (ROCK1) is targeted by miR-136-5p. The results of recovery experiments showed that ROCK1 overexpression partly rescued the impact of circTIMELESS silencing and miR-136-5p upregulation on proliferation and invasion. Consequently, our findings confirmed that circTIMELESS exists in LUSC and acts as a tumor promoter through the miR-136-5p/ROCK1 axis. Based on these findings, circTIMELESS may be potentially utilized as a therapeutic target for LUSC.     

Long noncoding RNA LINC00339 promotes laryngeal squamous cell carcinoma cell proliferation and invasion via sponging miR-145

Laryngeal squamous cell carcinoma (LSCC) is a very common neoplasm of the head and neck in the world. Long noncoding RNAs play key roles in cell infiltration, fate, apoptosis, and invasion. However, the functional role and expression of LINC00339 remains unclear in LSCC. In this study, we showed that the expression level of LINC00339 was upregulated in LSCC tissues and cell lines. LINC00339 silencing suppressed the proliferation, invasion, and epithelial-mesenchymal transition (EMT) progression of LSCC cells. In addition, we showed that LINC00339 acted as a sponge of miR-145, and LINC00339 silencing promoted the expression of miR-145 in Hep2 cell. Furthermore, the expression of miR-145 was lower in LSCC tissues than in their paired normal samples and the miR-145 expression level was negatively correlated with LINC00339 expression in LSCC tissues. The knockdown of miR-145 promoted the proliferation, invasion, and EMT progression of LSCC cells. Finally, we indicated that LINC00339 silencing inhibited the proliferation, invasion, and EMT progression of LSCC cells by suppressing the miR-145 expression. These data suggested that LINC00339 acted as an oncogene in the development of LSCC, partly by regulating the miR-145 expression.     

Expression and clinical value of PD-L1 which is regulated by BRD4 in tongue squamous cell carcinoma

The programmed cell death-ligand-1 (PD-L1) and bromodomain protein 4 (BRD4) are frequently overexpressed in cancer and have even been shown to act synergistically. The aim of this study was to determine their potential oncogenic role .in tongue squamous cell carcinoma (TSCC). We detected significantly higher expression levels of both PD-L1 and BRD4 in TSCC tissues compared to normal tissues (P ≤ .05). In addition, the high levels of PD-L1 were significantly associated with increased tumor lymphatic metastasis (P ≤ .05), tumor staging (P ≤ .01), as well as BRD4 expression (P ≤ .05). Genetic and pharmacological inhibition of BRD4 in TSCC cells not only reduced their growth rate but also PD-L1 levels (P ≤ .05), while overexpression of BRD4 upregulated PD-L1. Bioinformatics analysis showed that c-MYC and CDK9 were interactive partners of both BRD4 and PD-L1. While c-MYC clearly modulated the expression of PD-L1, as well as reversed the inhibitory effects of JQ1, no obvious association was observed between CDK9 and PD-L1. We report a novel regulatory axis consisting of BRD4, PD-L1, and c-MYC that likely drives TSCC progression, and is a potential prognostic marker and/or therapeutic target for TSCC.     

Retracted: CRNDE promotes cell tongue squamous cell carcinoma cell growth and invasion through suppressing miR-384

Tongue squamous cell carcinoma (TSCC) is the most common type of oral cancer and is an aggressive head and neck malignancy. Increasing studies have demonstrated that long noncoding RNAs (lncRNAs) play important roles in diverse biological cell processes, such as cell development, fate decisions, cell differentiation, cell migration, and invasion. In our study, we showed that long noncoding RNA colorectal neoplasia differentially expressed (CRNDE) expression was upregulated in TSCC cell lines and tissues. Overexpression of CRNDE increased the TSCC cell proliferation, cell cycle, and cell invasion. Moreover, ectopic expression of CRNDE inhibited the miR-384 expression in the SCC1 cell and increased the Kirsten Ras (KRAS), cell division cycle 42, and insulin receptor substrate 1 expression, which were the direct target genes of miR-384. We demonstrated that the miR-384 expression was downregulated in the TSCC samples compared with the paired adjacent nontumor samples. The expression of CRNDE was negatively correlated with the expression of miR-384 in the TSCC samples. Overexpression of miR-384 suppressed TSCC cell proliferation, cell cycle, and invasion. Furthermore, we demonstrated that CRNDE promoted TSCC cell proliferation and invasion through inhibiting miR-384 expression. These results suggested that CRNDE acts as an oncogene in the development of TSCC, which partially occurs through inhibiting miR-384 expression.     

LncRNA Erbb4-IR promotes esophageal squamous cell carcinoma (ESCC) by downregulating miR-145

Erbb4-IR is a recently identified lncRNA with pivotal functions in renal injury. The present study investigated the roles of Erbb4-IR in esophageal squamous cell carcinoma (ESCC). It was observed that Erbb4-IR was upregulated in tumor tissues of patients with ESCC. Plasma levels of Erbb4-IR in patients with ESCC were positively correlated with expression levels of Erbb4-IR in tumor tissues. MicroRNA-145 (miR-145) was downregulated in tumor tissues and inversely correlated with Erbb4-IR only in tumor tissues. Erbb4-IR overexpression led to downregulated miR-145, and increased rates of ECSS cell proliferation and decreased rates of ECSS cell apoptosis. Overexpression of miR-145 showed no significant effects on Erbb4-IR expression, but played an opposite role on cancer cell proliferation and apoptosis. In addition, miR-145 overexpression attenuated the effects of Erbb4-IR overexpression. Therefore, lncRNA Erbb4-IR may promote ESCC by downregulating miR-145.     

Clinicopathological and prognostic significance of PD-1/PD-L1 axis expression in patients with tongue squamous cell carcinoma

Tongue squamous cell carcinoma (TSCC) is more aggressive than other head and neck tumors, and the prognosis for patients with advanced TSCC is poor. At present, comprehensive treatment based on surgery as the main method is not effective for patients with advanced TSCC. The application of PD-1/PD-L1 immunocheckpoint inhibitor alone in patients with TSCC has not been reported. To explore the role of PD-1/PD-L1, we investigated the expression of PD-1 and PD-L1 in TSCC and analyzed the relationship between the expression of PD-1 and PD-L1 and the related clinicopathological parameters and survival prognosis. The expression of PD-1 was significantly associated with palindromia (p = .015) and maximum diameter (p = .043). The expression of PD-L1 in tumor cells was significantly associated with N stage (P = .024), chemotherapy (p = .032), and clinical stage (p = .019). The expression of PD-L1 in infiltrating lymphocytes was significantly associated with palindromia (p = .030). Univariate and multivariate Cox analyses for prognoses of patients showed significant prognostic factors of overall survival and relapse-free survival. The high expression of PD-L1 on infiltrating lymphocytes for OS and RFS was an independent protective factor for patients with TSCC. The high expression of PD-1 on infiltrating lymphocytes and clinical stage for OS and RFS were independent risk factors for patients with TSCC. The data provide a reference for clinical treatment of TSCC with immunotherapy.     

MicroRNA-24 targeting RNA-binding protein DND1 in tongue squamous cell carcinoma

Deregulations of microRNA have been frequently observed in tongue squamous cell carcinoma (TSCC), but their roles in tumorigenesis are not entirely clear. Here, we reported the up-regulation of miR-24 in TSCC. MiR-24 up-regulation reduced the expression of RNA-binding protein dead end 1 (DND1). Knockdown of miR-24 led to enhanced expression of DND1. The direct targeting of miR-24 to the DND1 mRNA was predicted bioinformatically and confirmed by luciferase reporter gene assays. Furthermore, the miR-24-mediated change in DND1 expression suppressed the expression of cyclin-dependent kinase inhibitor 1B (CDKN1B), and also led to enhanced proliferation and reduced apoptosis in TSCC cells.     

lncRNA RPSAP52 induced the development of tongue squamous cell carcinomas via miR-423-5p/MYBL2

Growing lncRNAs have been noted to involve in the initiation and development of several tumours including tongue squamous cell carcinomas (TSCCs). However, the biological role and mechanism of lncRNA RPSAP52 were not well-explained. We indicated that RPSAP52 was higher in TSCC samples compared with that in control samples. The higher expression of RPSAP52 was positively correlated with higher T stage and TNM stage. Ectopic expression of RPSAP52 induced TSCC cell growth and cycle and induced cytokine secretion including IFN-γ, IL-1β and IL-6, IL-8, IL-10 and TGF-β. We found that the overexpression of RPSAP52 suppressed miR-423-5p expression in SCC-4 cell. miR-423-5p was lower in TSCC samples compared with that in control samples, and miR-423-5p level was negatively correlated with higher T stage and TNM stage. Pearson's correlation indicated that miR-423-5p was negatively associated with that of RPSAP52 in TSCC tissues. Furthermore, MYBL2 was one direct gene of miR-423-5p and elevated expression of miR-423-5p suppressed MYBL2 expression and ectopic expression of RPSAP52 increased MYBL2 expression in SCC-4 cell. Finally, we illustrated that RPSAP52 overexpression promoted TSCC cell growth and cycle and induced cytokine secretion including IFN-γ, IL-1β and IL-6, IL-8, IL-10 and TGF-β via modulating MYBL2. These data provided new insight into RPSAP52, which may be one potential treatment target for TSCC.     

Curcumin inhibits oral squamous cell carcinoma SCC-9 cells proliferation by regulating miR-9 expression

Curcumin, a phytochemical derived from the rhizome of Curcuma longa, has shown anticancer effects against a variety of tumors. In the present study, we investigated the effects of curcumin on the miR-9 expression in oral squamous cell carcinoma (OSCC) and explored the potential relationships between miR-9 and Wnt/β-catenin pathway in curcumin-mediated OSCC inhibition in vitro. As the results shown, the expression levels of miR-9 were significantly lower in clinical OSCC specimens than those in the adjacent non-tumor tissues. Furthermore, our results indicated that curcumin inhibited OSCC cells (SCC-9 cells) proliferation through up-regulating miR-9 expression, and suppressing Wnt/β-catenin signaling by increasing the expression levels of the GSK-3β, phosphorylated GSK-3β and β-catenin, and decreasing the cyclin D1 level. Additionally, the up-regulation of miR-9 by curcumin in SCC-9 cells was significantly inhibited by delivering anti-miR-9 but not control oligonucleotides. Downregulation of miR-9 by anti-miR-9 not only attenuated the growth-suppressive effects of curcumin on SCC-9 cells, but also re-activated Wnt/β-catenin signaling that was inhibited by curcumin. Therefore, our findings would provide a new insight into the use of curcumin against OSCC in future.     

miR-204-5p regulates cell proliferation,invasion, and apoptosis by targeting IL-11 in esophageal squamous cell carcinoma

Esophageal cancer (EC) is the world's eighth most common malignant neoplasm and is ranked as the sixth leading cause of death related to cancer. Aberrant microRNA (miRNA) expression has been reported to be associated with esophageal squamous cell carcinoma. However, the molecular mechanism of miR-204-5p in esophageal squamous cell carcinoma (ESCC) is not clear. Therefore, the aim of this study was to investigate the potential role of miR-204-5p in ESCC. In the present study, we found that miR-204-5p could affect ESCC proliferation, invasion, apoptosis, and cell cycle in cell and mouse models. A dual-luciferase reporter assay showed that miR-204-5p expression was negatively correlated with interleukin-11 (IL-11) expression. IL-11 overexpression reversed the suppressive effects of miR-204-5p in the cell lines. These results indicated that miR-204-5p functions as a tumor suppressor by directly targeting IL-11 in ESCC.