Silencing circZFR inhibits the proliferation, migration and invasion of human renal carcinoma cells by regulating miR-206

Circular RNA hsa_circ_0008726 Targets the hsa-miR-206-3p/KLF4 Axis to Modulate 4,4'-Methylene Diphenyl Diisocyanate-Glutathione Conjugate-Induced Chemokine Transcription in Macrophages

Exposure to 4,4'-methylene diphenyl diisocyanate (MDI) in the workplace may lead to the development of occupational asthma (OA). However, the specific mechanism(s) by which MDI induces OA are poorly understood. Previous reports have demonstrated that MDI and MDI-glutathione (GSH) conjugate exposure downregulates endogenous human/murine (hsa/mmu)-microRNA(miR)-206-3p, resulting in the activation of mmu/hsa-miR-206-3p-regulated signaling pathways in macrophages. Circular RNAs (circRNAs) regulate many important biological processes by targeting endogenous miRs; however, whether MDI/MDI-GSH exposure may influence circRNA expressions is unknown. Several circRNAs have been identified that regulate hsa-miR-206-3p. We hypothesize that MDI-GSH conjugate exposure induces endogenous circRNA(s) to regulate hsa-miR-206-3p in macrophages. The expression of candidate hsa-miR-206-3p-binding circRNAs was determined from MDI-GSH conjugate-treated differentiated THP-1 macrophages using RT-qPCR. MDI-GSH exposures induced hsa_circ_0008726 and its host gene transcript DNAJB6, whereas other circRNA(s) examined were either not detected or unchanged. RNA-induced silencing complex-immunoprecipitation (RISC-IP) experiments confirm that hsa-miR-206-3p can bind to hsa_circ_0008726. The expressions of endogenous hsa-miR-206-3p, hsa-miR-206-3p-regulated KLF4, and KLF4-activated M2 macrophage-associated markers and chemokines were up-/down-regulated by transfection of hsa_circ_0008726 siRNAs or hsa_circ_0008726 overexpression plasmid in macrophages, respectively. These results suggest MDI-GSH exposure downregulates hsa-miR-206-3p via induction of endogenous hsa_circ_0008726/DNAJB6, resulting in the upregulation of hsa-miR-206-3p-mediated regulations in macrophages.

Circular non-coding RNA circ_0072088 serves as a ceRNA, targeting the miR-1225-5p/WT1 axis to regulate non-small cell lung cancer cell malignant behavior

BACKGROUND

Circular RNA (circRNA) circ_0072088 has been reported to be associated with NSCLC cell growth, migration, and invasion. However, the role and mechanism of circ_0072088 on NSCLC development have not yet been determined.

METHODS

Circ_0072088, microRNA-1225 (miR-1225-5p), and Wilms' tumor (WT1) suppressor gene level was detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Migration, invasion, and apoptosis were detected using transwell and flow cytometry assays. Matrix metallopeptidase 9 (MMP9), hexokinase 2 (HK2), and WT1 were examined using western blot assay. The biological role of circ_0072088 on NSCLC tumor growth was examined by the xenograft tumor model in vivo. Circular RNA Interactome and TargetScan were used to predict the binding between miR-1225-5p and circ_0072088 or WT1, followed by confirmation using a dual-luciferase reporter.

RESULTS

Circ_0072088 and WT1 were highly expressed in NSCLC tissues and cells, and miR-1225-5p was decreased. Knockdown of circ_0072088 might repress migration, invasion, and glycolysis, and facilitate apoptosis of NSCLC cells in vitro. Circ_0072088 silencing also blocked NSCLC tumor growth in vivo. Mechanistically, circ_0072088 acted as a sponge of miR-1225-5p to regulate WT1 expression.

CONCLUSION

Circ_0072088 knockdown could inhibit cell growth, migration, invasion, and glycolysis partially by regulating the miR-1225-5p/WT1 axis, thus providing a promising therapeutic target for NSCLC treatment.

Prognostic and clinicopathologic significance of circZFR in multiple human cancers

Background

Abnormally expressed in diverse cancers, circZFR has been correlated with clinical outcomes of cancer patients. Aim of this meta-analysis was to elucidate the prognostic role of circZFR in multiple human malignancies.

Methods

Literature retrieval was conducted by systematically searching on Pubmed, Web of Science, and the Cochrane Library up to December 2nd, 2021. Hazard ratios (HRs) or odds ratios (ORs) with 95% confidence intervals (CIs) were pooled to evaluate the association between circZFR expression and overall survival (OS). The reliability of the pooled results was assessed through sensitivity analysis and the publication bias was measured by Begg’s and Egger’s test.

Results

A total of seventeen studies comprising 1098 Chinese patients were enrolled in this meta-analysis. Results demonstrated that high circZFR expression was correlated with an unfavorable OS (HR = 2.14, 95% CI 1.74, 2.64). High circZFR expression predicted larger tumor size (OR = 2.79, 95% CI 1.52, 5.12), advanced clinical stage (OR = 3.38, 95% CI 1.49, 7.65), tendentiousness of lymph node metastasis (LNM) (OR = 3.08, 95% CI 2.01, 4.71), and malignant grade (OR = 3.18, 95% CI 1.09, 9.30), but not related to age, gender, and distant metastasis (DM).

Conclusions

High circZFR expression was associated with unfavorable OS and clinicopathologic parameters including tumor size, clinical stage, LNM, and histology grade, implicating a promising prognostic factor in cancers.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02733-9.

Circ_ZFR affects FABP7 expression to regulate breast cancer progression by acting as a sponge for miR-223-3p

BACKGROUND

Breast cancer (BC) is a common malignancy in women. Circular RNAs (circRNAs) have been reported to play a key role in the development of BC; however, the effect of circular RNA zinc finger RNA binding protein (circ_ZFR) in BC is unknown.

METHODS

Abundances of circ_ZFR, fatty acid binding protein 7 (FABP7), and microRNA-223-3p (miR-223-3p) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The circular structure of circ_ZFR was validated by RNase R treatment. Cell proliferation, migration, invasion, and apoptosis were assessed by colony formation, cell counting kit-8, Transwell, flow cytometry assays, respectively. All protein levels were determined by Western blot. Dual-luciferase reporter assay was used to confirm the relationship between miR-223-3p and circ_ZFR or FABP7. A xenograft model was established to understand the effect of circ_ZFR on BC cell growth in vivo.

RESULTS

The expression levels of circ_ZFR and FABP7 were higher in BC tissues and cell lines, whereas miR-223-3p expression was lower. Knockdown of circ_ZFR or FABP7 in BC cells reduced proliferation, migration, invasion, and epithelial mesenchymal transition (EMT), and induced apoptosis in vitro, whereas the opposite effects were observed in circ_ZFR-overexpressed cells. Furthermore, circ_ZFR might act as a sponge for miR-223-3p to regulate FABP7 expression, thereby promoting the progression of BC cells in vitro and in vivo.

CONCLUSION

Circ_ZFR might act as a miRNA sponge for miR-223-3p to regulate FABP7, thereby promoting proliferation, migration, invasion, and EMT of BC cells, and inhibiting cell apoptosis.

Cancer-associated fibroblast exosomes promote chemoresistance to cisplatin in hepatocellular carcinoma through circZFR targeting signal transducers and activators of transcription (STAT3)/ nuclear factor -kappa B (NF-κB) pathway

Chemoresistance in hepatocellular carcinoma (HCC) has been found to be influenced by exosomal transport of circRNAs. However, the role of circZFR in HCC chemoresistance still remains unclear. In the present study, circZFR was highly expressed in cisplatin (DDP)-resistant HCC cell lines and could regulate DDP resistance of the HCC cells. Also, circZFR was highly expressed in cancer-associated fibroblast (CAFs) and the exosome of CAFs. In addition, supplementation of CAFs in culture medium could promote DDP resistance of HCC cells. In vivo tumor xenograft experiments showed that knockdown of circZFR inhibited tumor growth and weakened DDP resistance, while CAFs-derived exosomes incubation increased the expression of circZFR, inhibited the STAT3/NF-κB pathway, promoted tumor growth, and enhanced DDP resistance. In general, CAFs-derived exosomes deliver circZFR to HCC cells, inhibit the STAT3/NF-κB pathway, and promote HCC development and chemoresistance. The results provided a new sight for the prevention and treatment of chemoresistance in HCC.

An Update on the Roles of circRNA-ZFR in Human Malignant Tumors

CircRNAs (circular RNAs) are single-stranded RNAs that form covalently closed loops and function as important regulatory elements of the genome through multiple mechanisms. Increasing evidence had indicated that circRNAs, which might serve as either oncogenes or tumor suppressors, played vital roles in the pathophysiology of human diseases, especially in tumorigenesis and progression. CircRNA-ZFR (circular RNA zinc finger RNA binding protein) is a circular RNA that had attracted much attention in recent years. It has been found that circRNA-ZFR was abnormally expressed in a variety of malignant tumors, and its dysregulated expression was closely related to tumor stage, cancer metastasis and patients’ prognosis. Recent studies had shown that aberrantly expressed circRNA-ZFR could regulate the malignant biological behaviors of tumors through various mechanisms; further exploration of circRNA-ZFR expression in tumors and its regulation on malignant biological behaviors such as tumor proliferation, invasion and drug resistance will provide new ideas for clinical tumors diagnosis and treatment.

Circ_0072088 knockdown contributes to cisplatin sensitivity and inhibits tumor progression by miR-944/LASP1 axis in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is an aggressive tumor that accounts for a high rate in cancer-related deaths. Cisplatin (CDDP) has been utilized to treat NSCLC. However, the efficacy of CDDP is usually restrained owing to the development of drug resistance. This study aims to reveal the molecular mechanism related to the resistance of NSCLC cells to CDDP.

METHODS

The expression levels of circRNA_0072088 (circ_0072088), microRNA-944 (miR-944) and LIM and SH3 protein 1 (LASP1) were detected by quantitative real-time PCR (qRT-PCR) in CDDP-resistant NSCLC tissues and cells. Protein expression was determined by Western blotting in CDDP-resistant NSCLC tissues and cells. The functional effects of circ_0072088, miR-944 and LASP1 on CDDP sensitivity and NSCLC progression were revealed by cell counting kit-8 (CCK-8), flow cytometry, cell colony formation, wound-healing and transwell invasion assays. The binding relationship between miR-944 and circ_0072088 or LASP1 was identified by a dual-luciferase reporter or RNA immunoprecipitation assay. The effects of circ_0072088 knockdown on tumor growth in vivo were analyzed by an in vivo tumor formation assay.

RESULTS

Circ_0072088 and LASP1 expression were significantly upregulated, while miR-944 expression was downregulated in CDDP-resistant NSCLC tissues and cells as compared to control groups. Circ_0072088 expression was significantly associated with tumor-node-metastasis stages and tumor size. Functionally, circ_0072088 knockdown improved CDDP sensitivity and repressed NSCLC cell malignancy, whereas miR-944 inhibitor hindered these effects. Mechanistically, circ_0072088 functioned as a sponge for miR-944 and miR-944 targeted LASP1. Circ_0072088 knockdown improved the sensitivity of tumor to CDDP in vivo.

CONCLUSION

Circ_0072088 silencing improved CDDP sensitivity and inhibited NSCLC progression by downregulating LASP1 expression through sponging miR-944. These data provided a novel insight into the study on the resistance of NSCLC to CDDP.

circZFR regulates thyroid cancer progression by the miR-16/MAPK1 axis

Previous studies have identified the dysregulation of various circRNAs in many types of human cancers including thyroid cancer (TC). Circular RNA ZFR (circZFR) serves as an oncogenic circRNA in TC. However, the detailed molecular mechanism of circZFR in TC progression remains to be further explored. CircZFR and miR-16 expressions in TC cells were analyzed through qRT-PCR. Cell viability, invasion, and apoptosis were detected using CCK-8, transwell invasion assay, and flow cytometry analysis, respectively. The relationship between circZFR and miR-16 was explored using luciferase reporter assay, RNA pull-down assay, and qRT-PCR. The relationship between miR-16 and mitogen-activated protein kinase 1 (MAPK1) was explored using luciferase reporter assay and western blot analysis. Results showed that circZFR was upregulated and miR-16 was downregulated in TC cells. CircZFR knockdown inhibited the viability and invasion and induced apoptosis in TC cells. CircZFR inhibited miR-16 expression by sponging miR-16 and miR-16 repressed MAPK1 expression by targeting MAPK1. Moreover, circZFR positively regulated MAPK1 expression in TC cells by serving as a ceRNA of miR-16. Mechanistically, circZFR knockdown-induced inhibition of cell viability and invasion and promotion of apoptosis were overturned after miR-16 downregulation and promotion of MAPK1. Collectively, circZFR knockdown retarded TC progression by sponging miR-16 and modulating MAPK1 expression.

circRNA-miRNA-mRNA in breast cancer

Among cancers, breast cancer has the highest incidence rate among women and poses a tremendous threat to women's health. Messenger RNA (mRNA), microRNA (miRNA) and circular RNA (circRNA) play vital roles in the progression of breast cancer through a variety of biological effects and mechanisms. Recently, the regulatory network formed by circRNAs, miRNAs and mRNAs has piqued attention and garnered interest. CircRNAs bind to miRNAs through a regulatory mechanism in which endogenous RNAs compete to indirectly regulate the expression of mRNA corresponding to downstream target genes of miRNAs, contributing to the progression of breast cancer. The circRNA-miRNA-mRNA axis may be a marker for the early diagnosis and prognosis of breast cancer and a potential breast cancer treatment target, providing unlimited possibilities for the development of breast cancer biomarkers and therapeutic strategies. This article reviews recent research progress on the circRNA-miRNA-mRNA axis as a regulatory network of competing endogenous RNAs in breast cancer. Herein, we focus on the mechanism and function of the circRNA-miRNA-mRNA axis in the occurrence and metastasis of breast cancer, and resistance to chemotherapy.

SNHG16 promotes cell proliferation and inhibits cell apoptosis via regulation of the miR-1303-p/STARD9 axis in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a common subtype of renal cell carcinoma (RCC) and causes many deaths. Numerous medical studies have suggested that long noncoding RNAs (lncRNAs) exert their biological functions on ccRCC. Herein, functions of lncRNA SNHG16 in ccRCC cells and the mechanism mediated by SNHG16 were investigated. The expression levels of SNHG16 and its downstream genes in ccRCC cells and RCC tissues were examined utilizing reverse transcription quantitative polymerase chain reaction analyses. Cell counting kit-8 and 5-Ethynyl-2'-deoxyuridine assays were performed to evaluate the proliferation of ccRCC cells, and flow cytometry analyses were employed to determine the apoptosis of ccRCC cells. Western blot analysis was applied to examine protein levels associated with cell proliferation and apoptosis. The combination between SNHG16 and miRNA as well as miRNA and its target gene were explored by luciferase reporter, RNA pull down, and RNA immunoprecipitation assays. The significant upregulation of SNHG16 was observed in RCC tissues and ccRCC cells. SNHG16 downregulation inhibited the proliferation and promoted the apoptosis of ccRCC cells. In addition, SNHG16 served as a competing endogenous RNA for miR-1301-3p, and STARD9 was a target gene of miR-1301-3p in ccRCC cells. SNHG16 upregulated STARD9 expression by binding with miR-1301-3p in ccRCC cells. Rescue assays validated that SNHG16 promoted ccRCC cell promotion and induced ccRCC cell apoptosis by upregulating STARD9 expression. In conclusions, SNHG16 promotes ccRCC cell proliferation and suppresses ccRCC cell apoptosis via interaction with miR-1301-3p to upregulate STARD9 expression in ccRCC cells.

Circ-ZFR Promotes Progression of Bladder Cancer by Upregulating WNT5A Via Sponging miR-545 and miR-1270

Background

Bladder cancer is one of the most common cancers all over the world. CircZFR is a circular RNA and has been implicated in tumor generation and invasion. However, the exact role of circZFR in the development of bladder cancer (BCa) remains unknown. This study aimed to investigate the function of circZFR in BCa, and further to probe into the association between circ-ZFR, miR-545/miR-1270 and WNT5A.

Methods

The expression of circZFR in BCa was quantified by qRT-PCR and was positively correlated with the prognosis of BCa patients. Next, the stable knockdown of circZFR BCa cell lines was established and the resulting capacities of proliferation, migration and invasion were measured. The association of circZFR with miR-1270/miR-545 was predicted by circinteractome prediction, and was confirmed by luciferase assay as well as RNA pull down assay. Furthermore, miRNA inhibitors, WNT5A overexpression and Pearson correlation analysis were used to examine the relationship between circZFR, miR-1270/miR-545 and WNT5A.

Results

The expression of CircZFR was up-regulated both in BCa tissues and in BCa cell lines, and was positively correlated with patient survival rates. Blocking of circZFR's expression by RNA inhibitors suppressed the proliferation, migration and invasion of BCa cells both in vitro and in vivo. On the other hand, overexpression of target miRNA supported that circZFR directly interact with miR-545 and miR-1270. Moreover, we demonstrated that circZFR promotes the progression of BCa by upregulating WNT5A's expression via sponging miR-545 and miR-1270.

Conclusions

CircZFR promotes the proliferation, migration and invasion of BCa cells by upregulating WNT5A signaling pathway via sponging miR-545 and miR-1270. These results provide new insights into the molecular mechanism of circZFR in BCa progression, and more important, a novel target for BCa clinical treatment.

Lung cancer cells and their sensitivity/resistance to cisplatin chemotherapy: Role of microRNAs and upstream mediators

Cisplatin (CP) is a well-known chemotherapeutic agent with excellent clinical effects. The anti-tumor activity of CP has been demonstrated in different cancers such as breast, cervical, reproductive, lung, brain, and prostate cancers. However, resistance of cancer cells to CP chemotherapy has led to its failure in eradication of cancer cells, and subsequent death of patients with cancer. Fortunately, much effort has been put to identify molecular pathways and mechanisms involved in CP resistance/sensitivity. It seems that microRNAs (miRs) are promising candidates in mediating CP resistance/sensitivity, since they participate in different biological aspects of cells such as proliferation, migration, angiogenesis, and differentiation. In this review, we focus on miRs and their regulation in CP chemotherapy of lung cancer, as the most malignant tumor worldwide. Oncogenic miRs trigger CP resistance in lung cancer cells via targeting various pathways such as Wnt/β-catenin, Rab6, CASP2, PTEN, and Apaf-1. In contrast, onco-suppressor miRs inhibit oncogene pathways such as STAT3 to suppress CP resistance. These topics are discussed to determine the role of miRs in CP resistance/sensitivity. We also describe the upstream modulators of miRs such as lncRNAs, circRNAs, NF-κB, SOX2 and TRIM65 and their association with CP resistance/sensitivity in lung cancer cells. Finally, the effect of anti-tumor plant-derived natural compounds on miR expression during CP sensitivity of lung cancer cells is discussed.

CircZFR functions as a sponge of miR-578 to promote breast cancer progression by regulating HIF1A expression

BACKGROUND

Breast cancer (BC) is the most common malignancy among women. Emerging studies have demonstrated that circular RNA (circRNA) zinc finger RNA binding protein (circZFR) serves as a crucial regulator in many human cancers. However, the role and mechanism of circZFR in BC tumorigenesis remain unclear.

METHODS

The levels of circZFR, miR-578 and hypoxia-inducible factor 1α (HIF1A) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell viability, colony formation, apoptosis, migration and invasion capacities in vitro were determined by using the Cell Counting Kit-8 (CCK-8), standard colony formation, flow cytometry and transwell assays, respectively. Glucose uptake, lactate product and adenosine triphosphate (ATP) levels of cells in vitro were measured using the commercial human assay kits. Targeted relationships among circZFR, miR-578 and HIF1A in BC cell lines were verified by dual-luciferase reporter and RNA pulldown assays. Animal studies were performed to assess the effect of circZFR on tumor growth in vivo.

RESULTS

Our data indicated that circZFR was overexpressed in BC tissues and cells, and the increased circZFR level predicted poor prognosis of BC patients. CircZFR silencing or miR-578 overexpression repressed BC cell viability, colony formation, migration, invasion, and glycolysis and enhanced cell apoptosis in vitro. CircZFR silencing also hampered tumor growth in vivo. Mechanistically, circZFR acted as a sponge of miR-578, and circZFR silencing hindered BC cell malignant behaviors by miR-578. HIF1A was a functional target of miR-578 in regulating BC cell viability, colony formation, migration, invasion, glycolysis and apoptosis in vitro. Furthermore, circZFR modulated HIF1A expression through sponging miR-578.

CONCLUSION

Our findings first identified that the silencing of circZFR suppressed BC malignant progression in vitro via the regulation of the miR-578/HIF1A axis, providing evidence for the crucial involvement of circZFR in BC pathogenesis.

Wnt/β-catenin signaling pathway promotes renal ischemia-reperfusion injury through inducing oxidative stress and inflammation response

Oxidative stress and inflammation response have been found to be associated with renal ischemia reperfusion (I/R) injury through an undefined mechanism. The aim of our study is to explore the influence of Wnt/β-catenin signaling pathway on oxidative stress and inflammation response during renal I/R injury. The results of our study demonstrated that oxidative stress was induced whereas antioxidative factors were suppressed by renal I/R injury. Besides, the transcriptions and activities of pro-inflammation factors were also upregulated by renal I/R injury. Interestingly, inhibition of Wnt/β-catenin signaling pathway significantly attenuated I/R-mediated oxidative stress and inflammation response. Therefore, our results report a novel pathway responsible for renal I/R injury. Inhibition of Wnt/β-catenin signaling pathway would be considered as an effective approach to regulate oxidative stress and inflammation response in reperfused kidney.

Circ_0072088 promotes the development of non-small cell lung cancer via the miR-377-5p/NOVA2 axis

Background

Non‐small cell lung cancer (NSCLC) is one of the leading causes of cancer‐related death globally. This study aimed to disclose the role of circular RNA circ_0072088 in NSCLC and illustrate its potential mechanism.

Methods

Quantitative real‐time polymerase chain reaction (qRT‐PCR) was applied to detect the expression of circ_0072088, zinc finger RNA binding protein (ZFR), microRNA‐377‐5p (miR‐377‐5p) and NOVA alternative splicing regulator 2 (NOVA2). The viability, colony formation, cell cycle, migration and invasion of NSCLC cells were measured by cell counting kit‐8 (CCK8) assay, colony formation assay, flow cytometry, wound healing assay and transwell invasion assay. Western blot assay was employed to examine the protein levels of proliferating cell nuclear antigen (PCNA), Cyclin D1, matrix metallopeptidase 2 (MMP2), MMP9 and NOVA2. The downstream targets of circ_0072088 and miR‐377‐5p were searched through using circular RNA Interactome and TargetScan databases, and the interaction between miR‐377‐5p and circ_0072088 or NOVA2 was confirmed by dual‐luciferase reporter assay and RNA immunoprecipitation (RIP) assay. in vivo tumor growth assay was used to evaluate the functions of circ_0072088 in the progression of NSCLC in vivo.

Results

GSE101586 dataset and the analysis of tissue specimens showed that circ_0072088 was aberrantly upregulated in tumor tissues of lung cancer and NSCLC. Circ_0072088 interference caused marked suppression on the proliferation and motility of NSCLC cells. Circ_0072088 could negatively regulate miR‐377‐5p through direct combination. Circ_0072088 contributed to the progression of NSCLC through sponging miR‐377‐5p. MiR‐377‐5p could directly interact with NOVA2, and the overexpression of NOVA2 overturned miR‐377‐5p‐mediated influence on NSCLC cells. Circ_0072088 facilitated the progression of NSCLC in vivo.

Conclusions

Circ_0072088 facilitated the proliferation and metastasis of NSCLC cells through upregulating NOVA2 via functioning as a competitive endogenous RNA (ceRNA) for miR‐377‐5p.

miR-429-CRKL axis regulates clear cell renal cell carcinoma malignant progression through SOS1/MEK/ERK/MMP2/MMP9 pathway

The pathogenesis and tumorigenesis of clear cell renal cell carcinoma (ccRCC) remain unclear. The deregulations of miR-429, a member of miR-200 family, and v-crk sarcoma virus CT10 oncogene homologue (avian)-like (CRKL), an adaptor protein of CRK family, are involved in the development, metastasis and prognosis of various cancers. Current study aimed to demonstrate the differential expressions of miR-429 and CRKL with their correlationship and molecular regulation mechanism in ccRCC malignancy. miR-429 and CRKL separately showed suppressing and promoting effects in ccRCC. Lower miR-429 expression and higher CRKL expression were negatively correlated in surgical cancerous tissues by promoting the advance of ccRCC. By binding to the 3'-UTR of CRKL, miR-429 reversely regulated CRKL for its functionalities in ccRCC cells. CRKL knockdown and overexpression separately decreased and increased the in vitro migration and invasion of 786-O cells, which were consistent with the influences of miR-429 overexpression and knockdown on 786-O through respectively downregulating and upregulating CRKL via SOS1/MEK/ERK/MMP2/MMP9 pathway. The enhancements of CRKL expression, migration and invasion abilities and SOS1/MEK/ ERK/MMP2/MMP9 activation induced by TGF-β stimulation in 786-O cells could be antagonized by miR-429 overexpression. Exogenous re-expression of CRKL abrogated miR-429 suppression on the migration and invasion of 786-O cells. Collectively, miR-429 deficiency negatively correlated with CRKL overexpression promoted the aggressiveness of cancer cells and advanced the clinical progression of ccRCC patients. miR-429-CRKL axial regulation provides new clues to the fundamental research, diagnosis and treatment of ccRCC.

Circ_0072083 interference enhances growth-inhibiting effects of cisplatin in non-small-cell lung cancer cells via miR-545-3p/CBLL1 axis

Background

Non-small-cell lung cancer (NSCLC) is one of the common cancers in the world. Circular RNA 0072083 (circ_0072083, circZFR) has been reported to be associated with the progression of NSCLC. In this study, we intended to explore the role and the potential mechanism of circ_0072083 in NSCLC.

Methods

Quantitative real time polymerase chain reaction (qRT-PCR) was performed to detect the expression of circ_0072083, its matching linear RNA (zinc finger RNA binding protein (ZFR)) and microRNA-545-3p (miR-545-3p) in NSCLC cells. The ability of colony formation in NSCLC cells was detected by colony formation assay. The apoptosis and cell cycle were measured by flow cytometry. The metastasis was determined by transwell migration and invasion assays. The protein expression of E-cadherin, N-cadherin, Vimentin and Cbl proto-oncogene like 1 (CBLL1) was examined by western blot assay. The interaction between miR-545-3p and circ_0072083 or CBLL1 was predicted by starBase or Targetscan software. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were applied to validate these interactions. Nude mice bearing tumors were used to confirm the role of circ_0072083 and cisplatin (DDP) in vivo.

Results

The level of circ_0072083 was higher in NSCLC tissues and cells relative to that in adjacent non-tumor tissues and normal lung cells. The transfection of si-circ_0072083 inhibited colony formation, cell cycle and metastasis while promoted the apoptosis of NSCLC cells stimulated by DDP. MiR-545-3p was a direct functional target of circ_0072083 in NSCLC cells. CBLL1 could bind to miR-545-3p in NSCLC cells. Circ_0072083 promoted the progression of NSCLC induced by DDP through sponging miR-545-3p and enhancing the enrichment of CBLL1 in vivo and in vitro.

Conclusion

Circ_0072083 depletion contributed to DDP-triggered inhibition of NSCLC tumor through miR-545-3p/CBLL1 axis.