MiR-133b regulates the proliferation, colony formation, and invasion of bladder cancer cells via inhibiting SOX4 / 中南大学学报(医学版)

OBJECTIVES@#Bladder cancer is one of the most common urothelial tumors with high incidence and mortality rates. Although it has been reported that microRNA (miR)-133b can regulate tumorigenesis of bladder cancer, the mechanism remains unclear. Sex-determining region Y-box transcription factor 4 (SOX4) exhibits an important role in tumorigenesis, but it is unclear whether SOX4 and miR-133b are associated with regulation of pathogenesis of bladder cancer. This study aims to determine the expressions of SOX4 and miR-133b in bladder cancer tissues and cells, investigate their effects on the proliferation, colony formation, and invasion of bladder cancer cells, and to explore the association between miR-133b and SOX4 in regulating biological featurss of bladder cancer cells.@*METHODS@#The bladder cancer and adjacent tissue samples of 10 patients who underwent surgical resection in the Second Xiangya Hospital of Central South Universty from Januray to June 2015 were obtained. The levels of miR-133b were tested by real-time PCR, and the protein levels of SOX4 were evaluated using Western blotting in bladder cancer tissues, matched adjacent tissues, and cell lines. The correlation between miR-133b expression and SOX4 expression in bladder cancer tissues was analyzed. Using the online database TargetScan, the relationship between SOX4 and miR-133b was predicted. MiR-133b mimics, miR-133b inhibitor, and short hairpin RNA (shRNA)-SOX4 were transfected into T24 cells by Lipofectamine 2000. The relationship between miR-133b and SOX4 was also verified by a dual-luciferase reporter assay. The proliferation of T24 cells cultured for 0, 12, 48, 72, and 96 h was evaluated by cell counting kit-8 (CCK-8) assay. The colony formation capacity of bladder cancer cells was tested after 14-day culture, and cell invasion capacity was evaluated with Transwell invasion assay.@*RESULTS@#Bladder cancer tissue and bladder cancer cells had low level of miR-133b but high level of SOX4, compared with matched adjacent tissues and normal bladder epithelial cells. A negative correlation between miR-133b mRNA and SOX4 protein levels in bladder cancer tissues was also found (r=-0.84). The results of online database TargetScan showed that miR-133b targets at SOX4, and overexpression of miR-133b significantly attenuated the expression of SOX4 in T24 cells. Both overexpression of miR-133b and knockdown of SOX4 significantly inhibited the proliferation, colony formation, and invasion capacity of bladder cancer cells in vitro. SOX4 down-regulation restored the effects of miR-133b inhibitor on the proliferation, colony formation, and invasion capacity of T24 cells.@*CONCLUSIONS@#The up-regulation of SOX4 contributes to the progression of bladder cancer, and miR-133b can regulate the proliferation, colony formation, and invasion of bladder cancer cells via inhibiting SOX4.

lncRNA MEG3 inhibits the growth of hepatocellular carcinoma cells by sponging miR-9-5p to upregulate SOX11

The long non-coding RNA (lncRNA) maternally expressed gene 3 (MEG3), a tumor suppressor, is critical for the carcinogenesis and progression of different cancers, including hepatocellular carcinoma (HCC). To date, the roles of lncRNA MEG3 in HCC are not well illustrated. Therefore, this study used western blot and qRT-PCR to evaluate the expression of MEG3, miR-9-5p, and Sex determining Region Y-related HMG-box 11 (SOX11) in HCC tissues and cell lines. RNA pull-down and luciferase reporter assay were used to evaluate these molecular interactions. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and flow cytometry detected the viability and apoptosis of HCC cells, respectively. The results showed that MEG3 and SOX11 were poorly expressed but miR-9-5p was highly expressed in HCC. The expression levels of these molecules suggested a negative correlation between MEG3 and miR-9-5p and a positive correlation with SOX11, confirmed by Pearson's correlation analysis and biology experiments. Furthermore, MEG3 could combine with miR-9-5p, and SOX11 was a direct target of miR-9-5p. Moreover, MEG3 over-expression promoted cell apoptosis and growth inhibition in HCC cells through sponging miR-9-5p to up-regulate SOX11. Therefore, the interactions among MEG3, miR-9-5p, and SOX11 might offer a novel insight for understanding HCC pathogeny and provide potential diagnostic markers and therapeutic targets for HCC.

Long Non-Coding RNA TUG1 Promotes Proliferation and Inhibits Apoptosis of Osteosarcoma Cells by Sponging miR-132-3p and Upregulating SOX4 Expression

PURPOSE: Long non-coding RNA taurine upregulated gene 1 (TUG1) is reported to be a vital regulator of the progression of various cancers. This study aimed to explore the exact roles and molecular mechanisms of TUG1 in osteosarcoma (OS) development. MATERIALS AND METHODS: Real-time quantitative PCR was applied to detect the expressions of TUG1 and microRNA-132-3p (miR-132-3p) in OS tissues and cells. Western blot was performed to measure protein levels of sex determining region Y-box 4 (SOX4). Cell viability was assessed using XTT assay. Cell apoptosis was evaluated using flow cytometry and caspase-3 activity detection assays. Bioinformatics analysis and luciferase reporter experiments were employed to confirm relationships among TUG1, miR-132-3p, and SOX4. RESULTS: TUG1 was highly expressed in human OS tissues, OS cell lines, and primary OS cells. TUG1 knockdown hindered proliferation and induced apoptosis in human OS cell lines and primary OS cells. Moreover, TUG1 inhibited miR-132-3p expression by direct interaction, and introduction of miR-132-3p inhibitor partly abrogated the effect of TUG1 knockdown on the proliferation and apoptosis of OS cells. Furthermore, SOX4 was validated as a target of miR-132-3p. Further functional analyses revealed that miR-132-3p inhibited proliferation and induced apoptosis of OS cells, while this effect was greatly abated following SOX4 overexpression. Moreover, TUG1 knockdown suppressed proliferation and promoted apoptosis by upregulating miR-132-3p and downregulating SOX4 in primary OS cells. CONCLUSION: TUG1 facilitated proliferation and suppressed apoptosis by regulating the miR-132-3p/SOX4 axis in human OS cell lines and primary OS cells. This finding provides a potential target for OS therapy.

Expresión del factor de transcripción SOX11: Su implicancia en el linfoma de células del manto / Expression of SOX11 transcription factor: Its implication in mantle cell lymphoma

El gen SOX11, perteneciente a la familia de genes SOXC, es un factor de transcripción involucrado en la neurogénesis embrionaria y el remodelado tisular, participando asimismo en el control de la proliferación celular. Su rol en la linfomagénesis es desconocido. Estudios recientes han mostrado expresión proteica nuclear aberrante y sobreexpresión de los niveles de transcripto de SOX11 en pacientes con linfoma de células del manto (LCM). Si bien la mayoría de estos linfomas presentan un curso clínico agresivo, existe un subgrupo de pacientes con enfermedad indolente, sugiriendo una mayor heterogeneidad de esta patología. Actualmente, existen contradicciones respecto de la asociación entre la expresión del gen SOX11 y la evolución clínica del LCM; mientras algunos autores relacionan la ausencia de expresión de SOX11 con buen pronóstico, otros lo encuentran asociado a un curso clínico adverso. Esta diferencia en la expresión estaría relacionada a mecanismos epigenéticos, metilación del ADN y modificaciones a nivel de histonas, que permitirían la expresión aberrante de este gen en algunas neoplasias linfoides, incluyendo LCM. La profundización del conocimiento del gen SOX11 en LCM hará factible, sin duda, lograr una mayor comprensión de los mecanismos involucrados en la patogénesis y/o progresión de este linfoma, así como del rol de SOX11 en estos procesos.

SOX11, belonging to the family of genes SOXC, is a transcript factor involved in the embryonic neurogenesis and tissue remodeling, also participating in the control of cell proliferation. Its role in lymphomagenesis still remains unknown. Recent studies have shown aberrant SOX11 nuclear protein expression as well as mRNA levels in patients with mantle cell lymphoma (MCL). Although the majority of these lymphomas have an aggressive clinical course, there is a subgroup of patients with an indolent clinical evolution, suggesting a greater heterogeneity of this disease. Currently, there are contradictions regarding the association of SOX11 gene expression and outcome in MCL, while some authors have related the lack of SOX11 expression with good prognosis, others find it associated with an adverse clinical course. This difference in the gene expression could be associated to epigenetic mechanisms such as modifications at the histone level and DNA methylation that would allow the aberrant expression of this gene in some lymphoid neoplasias, including LCM. More knowledge of gene SOX11 in LCM will lead to a greater understanding of those mechanisms involved in the pathogenesis and progression of this lymphoma, also the involvement of SOX11 in these processes.