miR-4429 Inhibits Tumor Progression and Epithelial-Mesenchymal Transition Via Targeting CDK6 in Clear Cell Renal Cell Carcinoma

CDK6 is a novel predictive and prognosis biomarker correlated with immune infiltrates in multiple human neoplasms, including small cell lung carcinoma

The roles of cyclin-dependent kinase 6 (CDK6) in various cancers, including small cell lung carcinoma (SCLC), remain unclear. Here, 111,54 multi-center samples were investigated to determine the expression, clinical significance, and underlying mechanisms of CDK6 in 34 cancers. The area under the curve (AUC), Cox regression analysis, and the Kaplan-Meier curves were used to explore the clinical value of CDK6 in cancers. Gene set enrichment analysis and correlation analysis were performed to detect potential CDK6 mechanisms. CDK6 expression was essential in 24 cancer cell types. Abnormal CDK6 expression was observed in 14 cancer types (e.g., downregulated in breast invasive carcinoma; p < 0.05). CDK6 allowed six cancers to be distinguished from their controls (AUC > 0.750). CDK6 expression was a prognosis marker for 13 cancers (e.g., adrenocortical carcinoma; p < 0.05). CDK6 was correlated with several immune-related signaling pathways and the infiltration levels of certain immune cells (e.g., CD8+ T cells; p < 0.05). Downregulated CDK6 mRNA and protein levels were observed in SCLC (p < 0.05, SMD = - 0.90). CDK6 allowed the identification of SCLC status (AUC = 0.91) and predicted a favorable prognosis for SCLC patients (p < 0.05). CDK6 may be a novel biomarker for the prediction and prognosis of several cancers, including SCLC.

Overexpressed lncRNA FTX promotes the cell viability, proliferation, migration and invasion of renal cell carcinoma via FTX/miR‑4429/UBE2C axis

The present study aimed to explore the role of long non‑coding (lnc)RNA FTX and ubiquitin‑conjugating enzyme E2C (UBE2C) in promoting the progression of renal cell carcinoma (RCC) and the underlying regulatory mechanism. Relative levels of lncRNA FTX, UBE2C, AKT, CDK1 and CDK6 in RCC cell lines were detected by reverse transcription‑quantitative (RT‑q). Expression levels of UBE2C, phosphorylated (p)‑AKT/AKT, p‑CDK1/CDK1 and p‑CDK6/CDK6 in RCC and paracancerous specimens and RCC cells were measured by western blot or immunohistochemistry assay. In addition, the proliferative rate, cell viability, cell cycle progression, migratory rate and invasive rate of RCC cells overexpressing lncRNA FTX by lentivirus transfection were determined by a series of functional experiments, including the colony formation assay, MTT assay, flow cytometry, Transwell assay and wound healing assay. The targeted binding relationship in the lncRNA FTX/miR‑4429/UBE2C axis was validated by dual‑luciferase reporter assay. By intervening microRNA (miR)‑4492 and UBE2C by the transfection of miR‑4429‑mimics or short interfering UBE2C‑2, the regulatory effect of lncRNA FTX/miR‑4429/UBE2C axis on the progression of RCC was evaluated. Finally, a xenograft model of RCC in nude mice was established by subcutaneous implantation, thus evaluating the in vivo function of lncRNA FTX in the progression of RCC. The results showed that lncRNA FTX and UBE2C were upregulated in RCC specimens and cell lines. The overexpression of lncRNA FTX in RCC cells upregulated UBE2C. In addition, the overexpression of lncRNA FTX promoted the cell viability and proliferative, migratory and invasive capacities of RCC cells and accelerated the cell cycle progression. A dual‑luciferase reporter assay validated that lncRNA FTX exerted the miRNA sponge effect on miR‑4429, which was bound to UBE2C 3'UTR. Knockdown of UBE2C effectively reversed the regulatory effects of overexpressed lncRNA FTX on the abovementioned phenotypes of RCC cells. In the xenograft model of RCC, the mice implanted with RCC cells overexpressing lncRNA FTX showed a larger tumor size and higher tumor weight than those of controls, while the in vivo knockdown of UBE2C significantly reduced the size of RCC lesions, indicating the reversed cancer‑promoting effect of lncRNA FTX. Overall, the present study showed that lncRNA FTX was upregulated in RCC and could significantly promote the proliferative, migratory and invasive capacities, enhancing the viability and accelerating the cell cycle progression of RCC cells by exerting the miRNA sponge effect on miR‑4429 and thus upregulating UBE2C. lncRNA FTX and UBE2C are potential molecular biomarkers and therapeutic targets of RCC.

Alpha Protein Kinase 2 Promotes Esophageal Cancer via Integrin Alpha 11

Background

As a common disease around the world, esophageal cancer (EC) primarily includes two subclasses: esophageal adenocarcinoma and esophageal squamous cell carcinoma. Mortality has been rising over the years; hence, exploring the mechanism of EC development has become critical. Among the alpha protein kinases, alpha protein kinase 2 (ALPK2) presumably has a connection with EC, but it has never been revealed before.

Methods

In this study, IHC analysis was used for ALPK2 expression quantification in ES tissues. TE-1 and Eca-109, which are both human EC cell lines, were used for in vitro analysis of cell proliferation, migration, apoptosis, and colony formation.

Results

ALPK2 was found to have an abundant expression within EC tissues (P < 0.001), as well as in the two selected human EC cell lines (P < 0.05). The data showed that ALPK2 depletion suppressed EC cell proliferation, migration, and colony formation, meanwhile stimulating apoptosis (P < 0.001). The in vivo experiments also displayed inhibitory effects caused by ALPK2 depletion on EC tumorigenesis (P < 0.001). It was further validated that ALPK2 depletion made the phosphorylation of Akt and mTOR, as well as CDK6 and PIK3CA levels downregulated (P < 0.001). Mechanistically, we identified integrin alpha 11 (ITGA11) as a downstream gene of ALPK2 regulating EC. More importantly, we found that ITGA11 elevation promoted cell proliferation and migration and rescued the suppression effects caused by ALPK2 depletion (P < 0.001).

Conclusions

ALPK2 promotes esophageal cancer via integrin its downstream gene alpha 11; ALPK2 can potentially act as a target for the treatment of EC.

Circ_0067680 expedites the osteogenic differentiation of human bone marrow-derived mesenchymal stem cells through miR-4429/CTNNB1/Wnt/β-catenin pathway

BACKGROUND

Human bone marrow-derived mesenchymal stem cells (hBMSCs) are the primary source of osteoblasts in vivo. Emerging literatures have unveiled that circular RNAs (circRNAs) are actively drawn in the osteogenic differentiation of mesenchymal stem cells (MSCs). This research mainly illuminated the role of circ_0067680 as well as its regulatory mechanism in osteoblastic differentiation.

METHODS

In this study, RT-qPCR was to measure the expression of circ_0067680. Functional assays were implemented to assess the role of circ_0067680 in osteogenic differentiation. Besides, RNA pull down, RIP and luciferase reporter assays were carried out to investigate the regulatory mechanism of circ_0067680.

RESULTS

Circ_0067680, which derived from its host gene divergent protein kinase domain 2A (C3orf58), was up-regulated during osteogenic differentiation of hBMSCs. Besides, circ_0067680 deficiency impeded the osteoblastic differentiation of hBMSCs. Moreover, circ_0067680 served as a ceRNA via sequestering miR-4429 to regulate the expression of catenin beta 1 (CTNNB1), thereby activating the Wnt/β-catenin signaling pathway.

CONCLUSION

Circ_0067680 accelerated hBMSCs osteogenic differentiation by the miR-4429/CTNNB1/Wnt/β-catenin signaling, which might be used as a potential biomarker for osteoblastic differentiation.

microRNA-4429-5p suppresses the malignant development of colon cancer by targeting matrix metalloproteinase 16

Colon cancer has been recognized as the major reason for global cancer-associated mortality. microRNA (miRNA, miR)-4429-5p has been documented to act as a tumor-suppressive miRNA in some cancers, but its effect on colon cancer remains elusive. In this study, the biological effects of miR-4429-5p were investigated both in vitro by MTT, 5-ethynyl-2'-deoxyuridine (EdU), wound healing, and transwell assays and in vivo by a xenograft mice model. Western blot, quantitative reverse transcription-polymerase chain reaction (qRT-PCR), and dual-luciferase assay were used to identify the binding of miR-4429-5p on matrix metalloproteinase 16 (MMP16) 3'-UTR. Our results suggested that overexpression of miR-4429-5p hindered colon cancer cell proliferation, migration, and invasion, whereas knockdown of miR-4429-5p exhibited the opposite effect in colon cancer cells. Mechanistically, miR-4429-5p directly bound to the 3'-UTR of MMP16 and led to inhibition of MMP16 protein. Overexpression of miR-4429-5p inhibited colon tumor growth by targeting MMP16. Taken together, our study revealed that miR-4429-5p prevented colon cancer progression through targeting MMP16, indicating miR-4429-5p as a promising target for treatment improvement for colon cancer.

Circulating microRNAs from the Molecular Mechanisms to Clinical Biomarkers: A Focus on the Clear Cell Renal Cell Carcinoma

microRNAs (miRNAs) are emerging as relevant molecules in cancer development and progression. MiRNAs add a post-transcriptional level of control to the regulation of gene expression. The deregulation of miRNA expression results in changing the molecular circuitry in which miRNAs are involved, leading to alterations of cell fate determination. In this review, we describe the miRNAs that are emerging as innovative molecular biomarkers from liquid biopsies, not only for diagnosis, but also for post-surgery management in cancer. We focus our attention on renal cell carcinoma, in particular highlighting the crucial role of circulating miRNAs in clear cell renal cell carcinoma (ccRCC) management. In addition, the functional deregulation of miRNA expression in ccRCC is also discussed, to underline the contribution of miRNAs to ccRCC development and progression, which may be relevant for the identification and design of innovative clinical strategies against this tumor.

MicroRNAs in Epithelial-Mesenchymal Transition Process of Cancer: Potential Targets for Chemotherapy

In the last decades, a kind of small non-coding RNA molecules, called as microRNAs, has been applied as negative regulators in various types of cancer treatment through down-regulation of their targets. More recent studies exert that microRNAs play a critical role in the EMT process of cancer, promoting or inhibiting EMT progression. Interestingly, accumulating evidence suggests that pure compounds from natural plants could modulate deregulated microRNAs to inhibit EMT, resulting in the inhibition of cancer development. This small essay is on the purpose of demonstrating the significance and function of microRNAs in the EMT process as oncogenes and tumor suppressor genes according to studies mainly conducted in the last four years, providing evidence of efficient target therapy. The review also summarizes the drug candidates with the ability to restrain EMT in cancer through microRNA regulation.

ILF3-AS1 promotes cell proliferation and inhibits cell apoptosis of breast cancer by binding with miR-4429 to upregulate RAB14

As one of the leading causes of cancer-related deaths among women, breast cancer accounts for a 30% increase of incidence worldwide since 1970s. Recently, increasing studies have revealed that the long non-coding RNA ILF3-AS1 is involved in the progression of various cancers. Nevertheless, the role of ILF3-AS1 in breast cancer remains largely unknown. In the present study, we found that ILF3-AS1 was highly expressed in breast cancer tissues and cells. ILF3-AS1 silencing inhibited breast cancer cell proliferation, migration and invasion, and promoted cell apoptosis. ILF3-AS1 bound with miR-4429 in breast cancer cells. Moreover, RAB14 was a downstream target of miR-4429, and miR-4429 expression was negatively correlated with RAB14 or ILF3-AS1 expression in breast cancer tissues. The result of rescue experiments demonstrated that overexpression of RAB14 can reverse the inhibitory effect of ILF3-AS1 knockdown on breast cancer cell proliferation, migration and invasion. Overall, ILF3-AS1 promotes the malignant phenotypes of breast cancer cells by interacting with miR-4429 to regulate RAB14, which might offer a new insight into the underlying mechanism of breast cancer.

Screening and clinical significance of lymph node metastasis-related genes within esophagogastric junction adenocarcinoma

Background

Despite recent improvements in treatment technologies, such as surgical resection and chemoradiotherapy, the prognosis of patients with esophagogastric junction adenocarcinoma (EJA) remains poor due to early lymph node metastasis. Since few studies have investigated genes associated with lymph node metastasis in EJA, we aimed to screen lymph node metastasis‐associated genes and clarify their expression status and prognostic significance in EJA.

Methods

The differential frequency of mutations between carcinoma and para‐carcinoma tissues from 199 cases with EJA was detected using targeted next‐generation sequencing (tNGS). Following a stratified analysis to determine that gender has no effect on the frequency of gene mutations, lymph node metastasis‐related genes, including CDK6, MET, NOTCH1, and LRP1B, were screened, and CDK6 and LRP1B were selected for further study as they displayed significant differences in mutation rates. Differences in their expression status were verified using immunohistochemical (IHC) staining in 18 CDK6‐ and 17 LRP1B‐mutated samples and a randomly matched control group.

Results

tNGS revealed that CDK6 and LRP1B mutation frequencies were significantly different between EJA cases with (N ≥ 1) or without (N = 0) lymph node metastasis. In particular, CDK6 mutation frequency was expected less, whereas that of LRP1B was remarkably higher in cases with stage N0 than in those with stage N ≥ 1. IHC staining confirmed significant differences in CDK6 and LRP1B expression status between the study and control cohorts. Chi‐square tests revealed that a high CDK6 expression status correlated significantly with smoking history (p = 0.044), T stage (p = 0.035), N stage (p = 0.000), and advanced TNM stage (p = 0.001) in EJA, whereas a high LRP1B expression status only correlated with BMI (p = 0.013) and N stage (p = 0.000). Furthermore, as confirmed by survival status investigation, a high LRP1B expression status predicted good prognosis, and a high CDK6 expression status was an independent predictor of poor prognosis in patients with EJA.

Conclusions

Taken together, the findings of this study demonstrate that a high CDK6 and LRP1B expression status promotes and inhibits lymph node metastasis in patients with EJA, respectively, suggesting that both CDK6 and LRP1B are significantly potential predictors of lymph node metastasis and prognosis in EJA.

NR2F2-AS1 accelerates cell proliferation through regulating miR-4429/MBD1 axis in cervical cancer

Cervical cancer is one of the most frequent malignant tumors in female. Increasing studies have demonstrated that long noncoding RNAs (lncRNAs) play a key role in the development of multiple cancers. Although some studies have confirmed that lncRNA NR2F2 antisense RNA 1 (NR2F2-AS1) is a pro-cancer gene in many cancers, the molecular mechanism of NR2F2-AS1 in cervical cancer has not been completely elucidated. In the present study, our results revealed that NR2F2-AS1 expression was up-regulated in cervical cancer tissues and cells, notably in patients with advanced cervical cancer. NR2F2-AS1 accelerated progression of cervical cancer by facilitating cell proliferation, migration, invasion, and EMT process, but inhibiting cell apoptosis. Moreover, NR2F2-AS1 acted as a molecular sponge of miR-4429 and methyl-CpG-binding domain protein 1 (MBD1) was a downstream target of miR-4429 in cervical cancer. Furthermore, there was a negative correlation between miR-4429 expression and NR2F2-AS1 or MBD1 expression in tumor tissues. Rescue experiments confirmed that MBD1 overexpression partly rescued NR2F2-AS1 knockdown-mediated inhibition of progression in cervical cancer. To sum up, these results suggested the potential mechanism of NR2F2-AS1 in cervical cancer and revealed that NR2F2-AS1 exerted its carcinogenic effect via regulating miR-4429/MBD1 axis, indicating a promising insight into the therapeutic target of cervical cancer.

MicroRNA-4429 suppresses proliferation of prostate cancer cells by targeting distal-less homeobox 1 and inactivating the Wnt/β-catenin pathway

Background

Emerging evidence suggests that microRNAs (miRNAs) play multiple roles in human cancers through regulating mRNAs and distinct pathways. This paper focused on the functions of miR-4429 in prostate cancer (PCa) progression and the molecules involved.

Methods

Expression of miR-4429 in PCa tissues and cells was determined. Upregulation of miR-4429 was introduced in PCa cells to examine its role in the malignant behaviors of cells. The putative target mRNA of miR-4429 involved in PCa progression was predicted from a bioinformatic system and validated through luciferase assays. Overexpression of distal-less homeobox 1 (DLX1) was further induced in cells to validate its implication in miR-4429-mediated events. The activity of Wnt/β-catenin pathway was determined.

Results

miR-4429 was poorly expressed in PCa tissues and cells. Artificial upregulation of miR-4429 significantly reduced proliferation, growth, invasion, migration and resistance to death of cancer cells and inactivated the Wnt/β-catenin pathway. DLX1 mRNA was found as a target of miR-4429. Upregulation of DLX1 restored the malignant behaviors of PCa cells which were initially suppressed by miR-4429, and it activated the Wnt/β-catenin pathway.

Conclusion

Our study highlights that miR-4429 inhibits the growth of PCa cells by down-regulating DLX1 and inactivating the Wnt/β-catenin pathway. This finding may offer novel insights into PCa treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00810-x.

MicroRNA-4429 restrains colorectal cancer cell invasion and migration via regulating SMAD3-induced epithelial-mesenchymal transition

Colorectal cancer (CRC) is one of the commonest human cancers and the fourth primary cause of cancer-related death. Previous studies have reported that miR-4429 develops anticancer function in follicular thyroid carcinoma and non-small cell lung cancer. However, whether miR-4429 is implicated in the CRC progression remains to be clarified. The aim of our current study was to explore the potential role of miR-4429 in CRC. According to the result of quantitative real-time polymerase chain reaction analysis, miR-4429 was expressed at a low level in CRC cells. Gain-of-function assays showed that the upregulation of miR-4429 inhibited cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) process in CRC, whereas miR-4429 inhibition led to the opposite results. It was uncovered from mechanism experiments that miR-4429 targeted forkhead box M1 (FOXM1) and therefore regulating SMAD family member 3 (SMAD3) expression. Rescue experiments elucidated that miR-4429 influenced cell proliferation, migration, invasion, and EMT process in CRC by targeting FOXM1 to inactivate SMAD3. In conclusion, our study revealed that miR-4429 targeted FOXM1 to decrease SMAD3 expression and thus impeding cell proliferation, migration, invasion, and EMT process of CRC cells.

MiR-370-5p inhibits the progression of breast cancer via targeting LUC7L3

Breast cancer is one of the most common malignancies and one of the leading causes of cancer-induced mortality among women. Over the past decades, the occurrence of breast cancer has been a significant increase. As documented in numerous researches, microRNAs (miRNAs) play vital roles in a wide range of biological processes associated with the occurrence and development of breast cancer. Nevertheless, the role of miR-370-5p in breast cancer remains obscure, and the possible molecular regulatory mechanism needs to be further explored. In this study, our results delineated that miR-370-5p was downregulated in breast cancer tissues and cell lines. Besides, miR-370-5p overexpression suppressed cell proliferation and invasion in breast cancer. MiR-370-5p downregulation exerted an opposite result. In addition, LUC7L3 was identified as a target gene for miR-370-5p. Similar with the results induced by miR-370-5p overexpression, LUC7L3 knockdown attenuated the proliferation and invasion ability of breast cancer cells. Moreover, the alternation of LUC7L3 expression reversed the regulatory effects of miR-370-5p on cell phenotypes in breast cancer. Overall, miR-370-5p may exert antitumor effect on breast cancer. Hence, miR-370-5p may serve as a novel therapeutic marker for the treatment of patients with breast cancer.

Long non‑coding RNA SNHG12 regulates cell proliferation, invasion and migration in endometrial cancer by targeting miR‑4429

Long non-coding RNA small nucleolar RNA host gene 12 (SNHG12) has been demonstrated to be oncogenic. The aim of the present study was to examine the effects of SNHG12 on the progression of endometrial cancer (EC). The expression levels of SNHG12 and microRNA (miR)-4429 were assessed in EC cell lines by reverse transcription-quantitative PCR. Plasmids, including SNHG12 short hairpin RNAs (shRNAs), shRNA negative control (NC), SNHG12 overexpression (OV), OV-NC, miR-4429 mimic and mimic-NC, were transfected into RL95-2 cells. Post-transfection, Cell Counting Kit-8, Transwell Matrigel and wound-healing assays were performed to assess cell proliferation, invasion and migration, respectively. Cell cycle phase distribution was assessed by flow cytometry. The protein expression levels of matrix metalloproteinase (MMP)2 and MMP9 were detected by western blotting. miR-4429 target genes were predicted by bioinformatics analysis using target prediction online tools; the findings of this analysis were verified using a dual-luciferase reporter system. Identified as a target of miR-4429, SNHG12 was overexpressed in EC cell lines with decreased expression of miR-4429. Further experiments demonstrated that SNHG12 silencing and overexpression of miR-4429 markedly suppressed proliferation, migration and invasion of RL95-2 cells, arrested cells in the G₁ phase, and markedly downregulated the expression of MMP2 and MMP9. The opposite effects were observed in miR-4429 mimic-transfected RL95-2 cells after SNHG12 was overexpressed. The findings of the present study established the role of SNHG12 and miR-4429 in EC. Therefore, targeting the SNHG12/miR-4429 axis could serve as a potential future therapeutic target for treatment of EC.

miR-4429 Regulates the Proliferation, Migration, Invasion, and Epithelial-Mesenchymal Transition of Cervical Cancer by Targeting FOXM1

BACKGROUND

miR-4429 acts as an inhibitor in many malignant tumors and participates in the biological processes of them, but the clinical value and potential molecular mechanism of miR-4429 in cervical cancer (CC) are still under investigation.

OBJECTIVE

To analyze the clinical value and molecular mechanism of miR-4429 in CC.

MATERIALS AND METHODS

A qRT-PCR assay was employed to determine the levels of miR-4429 and forkhead-box M1 (FOXM1) in CC tissues, CC cell lines (SiHa, CaSki, ME-180, and C33A) and human normal immortalized epithelial cell lines (HaCaT). The proliferation, migration, invasion, and apoptosis abilities of ME-180 and C33A cells were detected, and the epithelial-to-mesenchymal transition (EMT)-related proteins in the cells were also determined.

RESULTS

MiR-4429 acted as a tumor suppressor gene in CC tissues and cells and was linked to lymph node metastasis and International Federation of Gynecology and Obstetrics (FIGO) staging. The survival analysis revealed that lymph node metastasis, high FIGO staging, and low miR-4429 expression were all related to the unfavorable prognosis of the patients, and the dual-luciferase reporter assay revealed that FOXM1 was the target of miR-4429. Both overexpression of miR-4429 and knock-down of FOXM1 inhibited the proliferation, migration, invasion, and EMT of CCCs, and accelerated the apoptosis of them. Conversely, both knockdown of miR-4429 and overexpression of FOXM1 promoted those biological behaviors of the cells. Moreover, the rescue experiment revealed that the overexpression of FOXM1 reversed the influences of miR-4429 overexpression on the proliferation, migration, invasion, and EMT of CCCs.

CONCLUSION

miR-4429 acts as a tumor suppressor in CC and can directly target FOXM1 to regulate the proliferation, migration, invasion, apoptosis and EMT of CCCs, so miR-4429 is expected to be a new therapeutic target for CC.

SP1-DLEU1-miR-4429 feedback loop promotes cell proliferative and anti-apoptotic abilities in human glioblastoma

Mounting studies have revealed that long non-coding RNA (lncRNA) deleted in lymphocytic leukemia 1 (DLEU1) positively regulated the initiation and development of various human malignant tumors. Nevertheless, the function and mechanism of DLEU1 in human glioblastoma multiforme (GBM) remain elusive and ill-defined. The current study was designed to highlight the functional role and disclose the underlying molecular mechanism by which DLEU1 regulated GBM development. We found that DLEU1 was up-regulated in GBM and DLEU1 knockdown significantly inhibited GBM cell proliferation and induced apoptosis. As predicted by bioinformatics analysis and validated in mechanistic assays, SP1 could bind to the promoter region of DLEU1 to activate DLEU1 transcription. Additionally, miR-4429 was verified as a target gene of DLEU1 and negatively modulated by DLEU1. More importantly, miR-4429 overexpression repressed the mRNA and protein levels of SP1 via binding to the 3'UTR of SP1. Overexpression of SP1 or miR-4429 inhibitor could partly abolish the effect of DLEU1 knockdown on cell viability and apoptosis in GBM. Accordingly, our experimental data revealed that SP1-DLEU1-miR-4429 formed a feedback loop to promote GBM development, providing a new evidence for the role of DLEU1 in GBM.

MiR-4429 prevented gastric cancer progression through targeting METTL3 to inhibit m6A-caused stabilization of SEC62

Gastric cancer (GC) has been recognized as the major reason for global cancer-associated mortality. SEC62 homolog, preprotein translocation factor (SEC62) has been documented to possess carcinogenic functions in cancers, but its influence on GC remains elusive. Present study aimed to uncover the impact and mechanism of SEC62 in GC. We validated the upregulation of SEC62 in GC samples by GEPIA, and revealed its high level in GC cell lines. Functionally, depletion of SEC62 hindered proliferation and encouraged apoptosis in GC cells. Furthermore, we found through Starbase 3.0 and validated that methyltransferase like 3 (METTL3) interacted with SEC62 to induce the m⁶A on SEC62 mRNA, therefore facilitated the stabilizing effect of IGF2 binding protein 1 (IGF2BP1) on SEC62 mRNA. Moreover, we predicted through miRmap and validated that miR-4429 targeted and inhibited METTL3 to repress SEC62. Rescue assays demonstrated that miR-4429 inhibited GC progression through METTL3/SEC62 axis. Together, our study firstly revealed that miR-4429 prevented gastric cancer progression through targeting METTL3 to inhibit m⁶A-caused stabilization of SEC62, indicating miR-4429 as a promising target for treatment improvement for GC.

Downregulation of miR-216a-5p by long noncoding RNA PVT1 suppresses colorectal cancer progression via modulation of YBX1 expression

Purpose

Increasing evidence has demonstrated that microRNAs (miRNAs) are closely related to the occurrence and development of tumors. MiR-216a-5p, located at 2p16.1, has been shown to suppress proliferation of cancerous cells. However, its expression and function in colorectal cancer (CRC) remain unclear.

Materials and methods

The significance of miR-216a-5p in CRC was studied by analyzing miR-216a-5p expression in CRC tissues and its association with clinicopathological parameters. CRC cells, stably overexpressing miR-216a-5p, were evaluated for cell proliferation and metastasis using cell counting kit-8 (CCK-8) and transwell assay methods. Epithelial–mesenchymal transition (EMT) pathway was analyzed by Western blotting. Bioinformatics, quantitative real-time polymerase chain reaction (RT-qPCR), and luciferase reporter assay were performed to define the regulation of PVT1/miR-216a-5p/Y Box Binding Protein 1 (YBX1) axis in CRC.

Results

The expression of miR-216a-5p was found to be significantly downregulated in CRC and was correlated with the various stages and differentiation degree of the tumors. Moreover, the overexpression of miR-216a-5p could significantly inhibit the tumor growth, metastasis, and EMT progression in CRC. Furthermore, the expression of miR-216a-5p was negatively correlated with the expression of PVT1, and PVT1 could reverse tumor suppressive effect of miR-216a-5p in CRC cells. Finally, YBX1 might be the key target of PVT1/miR-216a-5p axis in CRC.

Conclusion

Downregulation of miR-216a-5p by PVT1 could suppress CRC progression via modulating YBX1 expression.