MicroRNA-141 inhibits tumor growth and minimizes therapy resistance in colorectal cancer

Apoptotic and antiproliferative effects of Inula viscosa L. water extract in the expression of microRnas on HCT 116 cell line: an in vitro study

In this study, the antiproliferative and apoptotic effects of Inula viscosa L. water extract (IVE) on HCT 116 has been examined, and the change in the expression of miRNAs. Phenolic compounds of IVE were determined as µg/g extract using by HPLC-DAD. Quantitative determination of apoptosis, cell viability, IC50 values and miRNAs of the cells were determined during 24, and 48 hours. IVE contain coumarin, rosmarinic acid and chlorogenic acid. According to the findings of our study, the expression of miR-21 and miR-135a1 was upregulated, and miR-145 was downregulated in HCT 116 cells (Control). Additionally, IVE was found to have significant potential in regulating miRNAs, downregulating miR-21, miR-31 and miR-135a1, and upregulating miR-145 in HCT-116 cells. All these results show that the anticancer effect of IVE via regulating miRNAs' expression has been demonstrated for the first time, and may be candidate biomarkers in colorectal cancer.

The inhibitory role of microRNA-141-3p in human cutaneous melanoma growth and metastasis through the fibroblast growth factor 13-mediated mitogen-activated protein kinase axis

Human cutaneous melanoma (CM) is a highly invasive malignancy arising from melanocytes, and accompanied by ever-increasing incidence and mortality rates worldwide. Interestingly, microRNAs (miRNAs) possess the ability to regulate CM cell biological functions, resulting in the aggressive progression of CM. Nevertheless, a comprehensive understanding of the underlying mechanism remains elusive. Accordingly, the current study sought to elicit the functional role of miR-141-3p in human CM cells in association with fibroblast growth factor 13 (FGF13) and the MAPK pathway. First, miR-141-3p expression patterns were detected in human CM tissues and cell lines, in addition to the validation of the targeting relationship between miR-141-3p and FGF13. Subsequently, loss- and gain-of-function studies of miR-141-3p were performed to elucidate the functional role of miR-141-3p in the malignant features of CM cells. Intriguingly, our findings revealed that FGF13 was highly expressed, whereas miR-141-3p was poorly expressed in the CM tissues and cells. Further analysis highlighted FGF13 as a target gene of miR-141-3p. Meanwhile, overexpression of miR-141-3p inhibited the proliferative, invasive, and migratory abilities of CM cells, while enhancing their apoptosis accompanied by downregulation of FGF13 and the MAPK pathway-related genes. Collectively, our findings highlighted the inhibitory effects of miR-141-3p on CM cell malignant properties via disruption of the FGF13-dependent MAPK pathway, suggesting a potential target for treating human CM.

The role of miR-200 family in the regulation of hallmarks of cancer

MiRNAs are short non-coding RNAs that regulate gene expression post-transcriptionally contributing to the development of different diseases including cancer. The miR-200 family consists of five members, miR-200a, miR-200b, miR-200c, miR-141, and miR-429. Their expression is dysregulated in cancer tissue and their level is altered in the body fluids of cancer patients. Moreover, the levels of miR-200 family members correlate with clinical parameters such as cancer patients' survival which makes them potentially useful as diagnostic and prognostic biomarkers. MiRNAs can act as either oncomiRs or tumor suppressor miRNAs depending on the target genes and their role in the regulation of key oncogenic signaling pathways. In most types of cancer, the miR-200 family acts as tumor suppressor miRNA and regulates all features of cancer. In this review, we summarized the expression pattern of the miR-200 family in different types of cancer and their potential utility as biomarkers. Moreover, we comprehensively described the role of miR-200 family members in the regulation of all hallmarks of cancer proposed by Hanahan and Weinberg with the focus on the epithelial-mesenchymal transition, invasiveness, and metastasis of tumor cells.

The Role and Interactions of Programmed Cell Death 4 and its Regulation by microRNA in Transformed Cells of the Gastrointestinal Tract

Data from GLOBOCAN 2020 estimates that there were 19.3 million new cases of cancer and 10.0 million cancer-related deaths in 2020 and that this is predicted to increase by 47% in 2040. The combined burden of cancers of the gastrointestinal (GI) tract, including oesophageal-, gastric- and colorectal cancers, resulted in 22.6% of the cancer-related deaths in 2020 and 18.7% of new diagnosed cases. Understanding the aetiology of GI tract cancers should have a major impact on future therapies and lessen this substantial burden of disease. Many cancers of the GI tract have suppression of the tumour suppressor Programmed Cell Death 4 (PDCD4) and this has been linked to the expression of microRNAs which bind to the untranslated region of PDCD4 mRNA and either inhibit translation or target the mRNA for degradation. This review highlights the properties of PDCD4 and documents the evidence for the regulation of PDCD4 expression by microRNAs in cancers of the GI tract.

Functional mechanism and clinical implications of miR-141 in human cancers

Cancer is caused by the abnormal proliferation of local tissue cells under the control of many oncogenic factors. MicroRNAs (miRNAs) are a class of evolutionarily conserved, approximately 22-nucleotide noncoding small RNAs that influence transcriptional regulationby binding to the 3'-untranslated region of target messenger RNA. As a member of the miRNA family, miR-141 acts as a suppressor or an oncomiR in various cancers and regulates cancer cell proliferation, apoptosis, invasion, and metastasis through a variety of signaling pathways, such as phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) and constitutive activation of nuclear factor-κB (NF-κB). Target gene validation and pathway analysis have provided mechanistic insight into the role of this miRNA in different tissues. This review also outlines novel findings that suggest miR-141 may be useful as a noninvasive biomarker and as a therapeutic target in several cancers.

MicroRNAs and drug resistance in colorectal cancer with special focus on 5-fluorouracil

Colorectal cancer is globally one of the most common cancers in all age groups. The current chemotherapy combinations for colorectal cancer treatment include 5-fluorouracil-based regimens; however, drug resistance remains one of the main reasons for chemotherapy failure and disease recurrence. Many studies have determined colorectal cancer chemoresistance mechanisms such as drug efflux, cell cycle arrest, DNA damage repair, apoptosis, autophagy, vital enzymes, epigenetic, epithelial-mesenchymal transition, stem cells, and immune system suppression. Several microRNAs affect drug resistance by regulating the drug resistance-related target genes in colorectal cancer. These drug resistance-related miRNAs may be used as promising biomarkers for predicting drug response or as potential therapeutic targets for treating patients with colorectal cancer. This work reviews and discuss the role of selected microRNAs in 5-fluorouracil resistance and their molecular mechanisms in colorectal cancer.

Downregulation of miRNA-14669 Reverses Vincristine Resistance in Colorectal Cancer Cells through PI3K/AKT Signaling Pathway

BACKGROUND

Vincristine (VCR) is a chemotherapeutic drug commonly used in the treatment of Colorectal Cancer (CRC). However, VCR drug resistance may result in reduced efficacy and even failure of chemotherapy in CRC treatment. MiRNA has been demonstrated to be associated with the sensitivity of tumor cells to chemotherapy.

OBJECTIVE

This study aimed to identify a novel miRNA-14669 that can reverse vincristine resistance and sensitize drug-resistant colorectal cancer cells.

METHODS

High-throughput sequencing was performed to screen miRNAs that are associated with VCR drug resistance, and qRT-PCR was used for further validation. The miRNA mimic and inhibitor were designed and transfected into HCT-8，HCT-116 and HCT-8/VCR cells. Wound healing test examined the effect of the miRNA on the migration of colorectal cancer cells. Flow cytometry was used to evaluate cell apoptosis of HCT-8 cells. Survivin, Bcl-2, GST3, MDR1 and MRP1 expressions were detected by Western blot.

RESULTS

The expression of miRNA-14669 in HCT-8/VCR cells was 1.925 times higher than that of the HCT-8 cells. After transfecting with mimic miRNA, HCT-8 and HCT-116 cells showed an increased survival rate. The survival rate of HCT-8/VCR cells decreased by transfection of inhibitor. The inhibitor also sensitized HCT-8 and HCT-116 cells to VCR or 5-Fluorouracil (5-FU). The migratory ability of HCT-8 and HCT-116 cells increased by miRNA mimic while reduced by miRNA inhibitor. Overexpression of miRNA-14669 reduced apoptosis, while downregulation of miRNA-14669 increased cell apoptosis in HCT-8 cells. The mechanism of the miRNA involved in drug resistance may be attributed to apoptosis of tumor cells, detoxification of GST3 and drug efflux induced by MDR1 and MRP1. PI3K / AKT is the signaling pathway related to drug resistance.

CONCLUSION

We identified a novel miRNA-14669 that may be associated with the chemotherapeutic resistance in CRC cells.

Differential expression and role of miR-200 family in multiple tumors

microRNA (miRNA) can maintain the homeostasis of the human by participating in the regulation of cell proliferation, apoptosis, differentiation, and metabolism. During the entire stage of tumorigenesis, miRNA can maintain the heterogeneity of cancer stem cells by regulating the formation and metastasis of the tumor, which leads to chemotherapy resistance. miR-200 family consists of five members, which can regulate the proliferation, invasion, and migration of cancer cells by inhibiting the transcription of downstream genes (including zinc finger E-box binding homeobox 1 and 2, E-cadherin, N-cadherin, transforming growth factor-β, and cancer stem cell related-proteins). Meanwhile, Long non-coding RNA can bind to miR-200s to regulate the proliferation and apoptosis of cancer cells. Besides, the expression of the miR-200 family can affect the mechanism of chemotherapy resistance.

Cancer stem cells in colorectal cancer and the association with chemotherapy resistance

The incidence and mortality of colorectal cancer (CRC) have always been among the highest in the world, although the diagnosis and treatment are becoming more and more advanced. At present, the main reason is that patients have acquired drug resistance after long-term conventional drug treatment. An increasing number of evidences confirm the existence of cancer stem cells (CSCs), which are a group of special cells in cancer, only a small part of cancer cells. These special cell populations are not eliminated by chemotherapeutic drugs and result in tumor recurrence and metastasis after drug treatment. CSCs have the ability of self-renewal and multidirectional differentiation, which is associated with the occurrence and development of cancer. CSCs can be screened and identified by related surface markers. In this paper, the characteristic surface markers of CSCs in CRC and the related mechanism of drug resistance will be discussed in detail. A better understanding of the mechanism of CSCs resistance to chemotherapy may lead to better targeted therapy.

Molecular mechanisms and clinical implications of miRNAs in drug resistance of colorectal cancer

Systemic chemotherapy is identified as a curative approach to prolong the survival time of patients with colorectal cancer (CRC). Although great progress in therapeutic approaches has been achieved during the last decades, drug resistance still extensively persists and serves as a major hurdle to effective anticancer therapy for CRC. The mechanism of multidrug resistance remains unclear. Recently, mounting evidence suggests that a great number of microRNAs (miRNAs) may contribute to drug resistance in CRC. Certain of these miRNAs may thus be used as promising biomarkers for predicting drug response to chemotherapy or serve as potential targets to develop personalized therapy for patients with CRC. This review mainly summarizes recent advances in miRNAs and the molecular mechanisms underlying miRNA-mediated chemoresistance in CRC. We also discuss the potential role of drug resistance-related miRNAs as potential biomarkers (diagnostic and prognostic value) and envisage the future orientation and challenges in translating the findings on miRNA-mediated chemoresistance of CRC into clinical applications.

LncRNA CDKN2B-AS1/miR-141/cyclin D network regulates tumor progression and metastasis of renal cell carcinoma

The molecular heterogeneity of renal cell carcinoma (RCC) complicates the therapeutic interventions for advanced metastatic disease and thus its management remains a significant challenge. This study investigates the role of the lncRNA CDKN2B-AS1 and miR-141-3p interactions in the progression and metastasis of kidney cancer. Human renal cancer cell lines (ACHN and Caki1), normal RPTEC cells, tissue cohorts, and a series of in vitro assays and in vivo mouse model were used for this study. An overexpression of CDKN2B-AS1 was observed in RCC compared to normal samples in TCGA and our in-house SFVAMC tissue cohorts. Reciprocally, we observed reduced expression of miR-141 in RCC compared to normal in the same cohorts. CDKN2B-AS1 shares regulatory miR-141 binding sites with CCND1 and CCND2 genes. Direct interactions of CDKN2B-AS1/miR-141/Cyclin D1-D2 were confirmed by RNA immunoprecipitation and luciferase reporter assays indicating that CDKN2B-AS1/miR-141/Cyclin D1-D2 acts as a ceRNA network in RCC. Functionally, attenuation of CDKN2B-AS1 and/or overexpression of miR-141 inhibited proliferation, clonogenicity, migration/invasion, induced apoptosis in vitro and suppressed tumor growth in xenograft mouse model. Further, overexpression of CDKN2B-AS1 is positively correlated with poor overall survival of RCC patients. Expression of miR-141 also robustly discriminated malignant from non-malignant tissues and its inhibition in normal RPTEC cells induced pro-cancerous characteristics. CDKN2B-AS1 attenuation or miR-141 overexpression decreased CCND1/CCND2 expression, resulting in reduced RAC1/pPXN that are involved in migration, invasion and epithelial-mesenchymal transition. This study, for the first time, deciphered the role of CDKN2B-AS1/miR-141/Cyclin D axis in RCC and highlights this network as a promising therapeutic target for the regulation of EMT driven metastasis in RCC.

KLF4 p.A472D Mutation Contributes to Acquired Resistance to Cetuximab in Colorectal Cancer

With the increase of treatment course, resistance to EGFR blockade is inevitable in patients with metastatic colorectal cancer (mCRC). KRAS mutations have been considered to be primary drivers of this resistance; however, the potential function of other genes has not been extensively investigated. This study collected 17 plasma samples from patients with mCRC with cetuximab resistance, and target-capture deep sequencing was used to identify mutations in circulating tumor DNA (ctDNA). Analysis of mutational prevalence in ctDNA was performed from three colorectal cancer tissue-based datasets and one ctDNA dataset. The prevalence of mutations identified in ctDNA was consistent with both colorectal cancer tissue-based and ctDNA datasets. Clonal analysis revealed that 41.2% of patients were positive for at least one subclone. Multiple mechanisms of cetuximab resistance were coexisted in individual patients, and one of the patients even harbored nine distinct mutations. In particular, functional study of Krüppel-like factor 4 (KLF4) p.A472D revealed increased cetuximab resistance in colorectal cancer cells, which was associated with the increased phosphorylation of downstream EGFR signaling proteins. These results suggest that KLF4 p.A472D may contribute to cetuximab resistance in patients with mCRC and thus may serve as a new biomarker in clinical application. Monitoring somatic mutations related to cetuximab resistance in patients with mCRC through ctDNA may provide real-time insights for clinical reference and treatment planning.

MicroRNA-1181 supports the growth of hepatocellular carcinoma by repressing AXIN1

Micro-RNAs regulate multiple biological behaviors of cancers, making them potential targets of new cancer therapies. MiR-1181 has been demonstrated to perform oncogenic or tumor-suppressing function in a tissue-dependent way, but its role in hepatocellular carcinoma (HCC) was unclear. Here, we showed that miR-1181 was significantly overexpressed in HCC tissues when compared with tumor-adjacent normal ones or normal liver tissues from donated organ, and that inhibition of miR-1181 could repress the growth of HCC cells. Through bioinformatics analysis and luciferase reporter assays, we found that axis inhibition protein 1 (AXIN1) was a direct target of miR-1181, and the expression of AXIN1 showed a negative correlation with that of miR-1181 in HCC. Therefore, these data indicated an oncogenic function of miRNA-1181 in the development of HCC and a potential target for the clinical treatment of HCC.

Current Evidence on miRNAs as Potential Theranostic Markers for Detecting Chemoresistance in Colorectal Cancer: A Systematic Review and Meta-Analysis of Preclinical and Clinical Studies

BACKGROUND

Findings from observational clinical studies examining the relationship between biomarker expression and theranosis in colorectal cancer (CRC) have been conflicting.

OBJECTIVE

We conducted this systematic review and meta-analysis to summarise the existing evidence to demonstrate the involvement of microRNAs (miRNAs) in chemoresistance and sensitivity in CRC through drug genetic pathways.

METHODS

Using PRISMA guidelines, we systematically searched PubMed and Science Direct for relevant studies that took place between 2012 and 2017. A random-effects model of meta-analysis was applied to evaluate the pooled effect size of hazard ratios (HRs) across the included studies. Cochran's Q test and the I² statistic were used to detect heterogeneity. A funnel plot was used to assess potential publication bias.

RESULTS

Of the 4700 studies found, 39 studies comprising 2822 patients with CRC met the inclusion criteria. The included studies used one or a combination of 14 chemotherapy drugs, including 5-fluorouracil and oxaliplatin. Of the 60 miRNAs, 28 were associated with chemosensitivity, 20 with chemoresistance, and one with differential expression and radiosensitivity; ten miRNAs were not associated with any impact on chemotherapy. The results outline the importance of 34 drug-regulatory pathways of chemoresistance and sensitivity in CRC. The mean effect size was 0.689 (95% confidence interval 0.428-1.110), indicating that the expression of miRNAs decreased the likelihood of death by about 32%.

CONCLUSION

Studies have consistently shown that multiple miRNAs could act as clinical predictors of chemoresistance and sensitivity. An inclusion of supplementary miRNA estimation in CRC routine practice needs to be considered to evaluate the efficacy of chemotherapy after confirming our findings with large-scale prospective cohort studies.

PROSPERO REGISTRATION NUMBER

CRD42017082196.

Theragnosis by a miR-141-3p molecular beacon: simultaneous detection and sensitization of 5-fluorouracil resistant colorectal cancer cells through the activation of the TRIM13-associated apoptotic pathway

We developed a molecular beacon targeting miR-141-3p, aberrantly increased in 5-fluorouracil-resistant colorectal cancer cells (R-CRCCs). It consists of a fluorophore-labeled oligonucleotide, antisense to miR-141-3p, and a quencher. It detected R-CRCCs and recovered the chemosensitivity of them to 5-fluorouracil by hybridization with miR-141-3p, which is applicable to cancer treatment.

MicroRNA-744 Inhibits Cellular Proliferation and Invasion of Colorectal Cancer by Directly Targeting Oncogene Notch1

Accumulated studies have strongly implicated aberrantly expressed microRNAs (miRNAs) in carcinogenesis and cancer progression of various cancers, including colorectal cancer (CRC). Hence, a comprehensive study of miRNAs and their association with CRC may be a promising therapeutic method for patients with this malignancy. MicroRNA-744 (miR-744) is abnormally expressed in several types of human cancer. Thus far, little is known about the expression, biological roles, and exact mechanisms of miR-744 in CRC. Thus, the present study measured the expression level of miR-744 and investigated its roles and associated molecular mechanisms in CRC. This study demonstrated that miR-744 expression was significantly underexpressed in CRC tissues and cell lines. Low miR-744 expression was positively associated with lymphatic metastasis and TNM stage. Functional experiments revealed that miR-744 overexpression obviously inhibited the proliferation and invasion of CRC cells. Furthermore, Notch1 was identified as a direct target of miR-744 in CRC. Moreover, the inhibition of Notch1 phenocopied the inhibitory effects of miR-744 overexpression on CRC cells. Restored Notch1 expression markedly rescued the tumor-suppressive effects of miR-744 overexpression on CRC cells. Overall, miR-744 exhibits an essential role in CRC progression, and the miR-744/Notch1 axis may provide novel insights into future treatments for patients with CRC.

HOXC13 promotes proliferation of lung adenocarcinoma via modulation of CCND1 and CCNE1

In this study, we confirmed that HOXC13 might be a potential oncogene in lung adenocarcinoma through an analysis of The Cancer Genome Atlas (TCGA) datasets. Further analysis revealed that the expression of HOXC13 was significantly higher in lung adenocarcinoma tissues than in adjacent normal tissues; importantly, its expression correlated with poor clinical characteristics and worse prognosis. In vitro experiments showed that HOXC13 expression generally increased in lung adenocarcinoma cell lines. Moreover, knockdown of HOXC13 inhibited lung adenocarcinoma cell proliferation, and induced G1-phase arrest via downregulation of CCND1 and CCNE1. Conversely, HOXC13 overexpression promoted lung adenocarcinoma cell proliferation, and decreased the percentage of cells in G1-phase via upregulation of CCND1 and CCNE1. We also found that miR-141 downregulated HOXC13, by directly targeting its 3'UTR, and inhibited proliferation of lung adenocarcinoma cells. Taken together, our results suggest that HOXC13, which is directly targeted by miR-141, is highly expressed in lung adenocarcinoma, and promotes proliferation of lung adenocarcinoma by modulating the expression of CCND1 and CCNE1.