MiR-200b Inhibits Tumor Growth and Chemoresistance via Targeting p70S6K1 in Lung Cancer

Sex differences in the tumor promoting effects of tobacco smoke in a cRaf transgenic lung cancer disease model

Tobacco smoke (TS) is the leading cause for lung cancer (LC), and female smokers are at a greater risk for LC. Yet, the underlying causes are unknown. We performed whole genome scans in TS exposed wild type and histologically characterized tumor lesions of cRaf transgenic mice. We constructed miRNA-gene and transcription factor-miRNA/gene regulatory networks and determined sex-specific gene regulations by evaluating hormone receptor activities. We validated the findings from TS exposed cRaf mice in a large cohort of smoking and never-smoking LC patients. When compared to males, TS prompted a sevenfold increase in tumor multiplicity in cRaf females. Genome-wide scans of tumor lesions identified 161 and 53 genes and miRNAs, which code for EGFR/MAPK signaling, cell proliferation, oncomirs and oncogenes, and 50% of DEGs code for immune response and tumor evasion. Outstandingly, in transgenic males, TS elicited upregulation of 20 tumor suppressors, some of which are the targets of the androgen and estrogen receptor. Conversely, in females, 18 tumor suppressors were downregulated, and five were specifically repressed by the estrogen receptor. We found TS to perturb the circadian clock in a sex-specific manner and identified a female-specific regulatory loop that consisted of the estrogen receptor, miR-22-3p and circadian genes to support LC growth. Finally, we confirmed sex-dependent tumor promoting effects of TS in a large cohort of LC patients. Our study highlights the sex-dependent genomic responses to TS and the interplay of circadian clock genes and hormone receptors in the regulation of oncogenes and oncomirs in LC growth.

Prospects of microRNAs as therapeutic biomarkers in non-small cell lung cancer

Lung Cancer, the second most common cancer worldwide, remains the leading cause of cancer-related deaths, contemporarily. More than 85% of identified lung cancer cases are comprised of non-small-cell lung carcinoma (NSCLC). Despite the best advancements in the realm of NSCLC therapy, the five-year survival period of NSCLC patients remains unchanged. Underlying complex molecular heterogeneity, delay in early detection resulting in progression of the disease to its advanced stage and acquired resistance of NSCLC cells during therapy have posed additional challenges for circumventing the discrepancies in treatment strategy. microRNAs (miRNAs) are a class of non-coding RNAs, identified as molecules playing an indispensable role in tumorigenesis & progression and metastasis of several cancers, including NSCLC, either by possessing tumor suppressor or by oncogenic functions. As observed across several studies, miRNA dysregulation has been recognised as a causative mechanism behind NSCLC tumorigenesis. In this review, we discuss the role of miRNAs in NSCLC tumor progression caused by their dysregulation, thereby stating their potential therapeutic application in NSCLC as therapeutic biomarkers. We have also highlighted the recent findings of some of the most widely studied tumor suppressor (miR-486, miR-7 miR-34), and oncogene miRNAs (miR-21, miR-224, miR-135b) that can be further explored for its therapeutic potentialities in the management of NSCLC.

Vitamin D deficiency contributes to the diabetic kidney disease progression via increase ZEB1/ZEB2 expressions

BACKGROUND

Diabetic kidney disease (DKD) remains one of the main causes of end-stage renal disease (ESRD) and mortality in diabetic patients worldwide. Vitamin D deficiency (VitDD) is one of the main consequences of different chronic kidney disease (CKD) types and is associated with rapid progression to ESRD. Nevertheless, the mechanisms that lead to this process are poorly understood. This study aimed to characterize a model of diabetic nephropathy progression in VitDD and the epithelial-mesenchymal-transition (EMT) role in these processes.

METHODS

Wistar Hannover rats received a diet with or without VitD before type 1 diabetes (T1D) induction. After this procedure, the rats were accompanied for 12 and 24 weeks after T1D induction and the renal function, structure, cell transdifferentiating markers and zinc finger e-box binding homeobox 1/2 (ZEB1/ZEB2) contribution to kidney damage were evaluated during the DKD progression.

RESULTS

The results showed an increase in glomerular tuft, mesangial and interstitial relative areas and renal function impairment in VitD-deficient diabetic rats compared to diabetic rats that received a VitD-containing diet. These alterations can be associated with increased expression of EMT markers, ZEB1 gene expression, ZEB2 protein expression and TGF-β1 urinary excretion. Decreased miR-200b expression, an important post-transcriptional regulator of ZEB1 and ZEB2 was also observed.

CONCLUSION

Our data demonstrated that VitD deficiency contributes to the rapid development and progression of DKD in diabetic rats induced by increase ZEB1/ZEB2 expressions and miR-200b downregulation.

Dysregulation of MiR-199a/IL8 pathway in chronic Cr (VI)-induced tumor growth and angiogenesis

Hexavalent chromium [Cr(VI)] is a well-known environmental carcinogen. Recent studies revealed that chronic exposure of human bronchial epithelial cells (BEAS-2B, B2B) to Cr(VI) activated several signaling pathways and induced cell malignant transformation and tumor growth. However, new mechanisms of Cr(VI) in inducing carcinogenesis remains to be elucidated. This study showed that miR-199a expression levels were significantly lower in Cr(VI)-transformed Cr-T cells. By using the mouse model, the expression levels of miR-199a were significantly decreased in blood samples and lung tissues of mice intranasally exposed to Cr(VI) for 12 weeks compared to the solvent exposure control. Overexpression of miR-199a inhibited tube formation and angiogenesis. C-X-C motif chemokine ligand 8 (CXCL8, IL8) levels were significantly higher in blood samples of Cr (VI)-exposed workers compared to normal workers, and forced expression of miR-199a in the cells suppressed IL8 levels. miR-199a suppression induced expression of hypoxia-inducible factor 1α (HIF-1α) and nuclear factor kappa B (NF-κB) p65 to increase IL8 expression. With animal experiment, the results showed that miR-199a overexpression inhibited tumor growth and angiogenesis through inhibiting IL8, HIF-1α and NF-κB p65 expression in vivo. These results show that miR-199a/IL8 pathway is important in Cr(VI)-induced carcinogenesis and angiogenesis.

microRNA-497 slows esophageal cancer development and reverses chemotherapy resistance through its target QKI

Esophageal cancer (EC) is considered one of the most lethal cancers in human beings, and multiple miRNAs have been investigated to be involved in EC development by targeting their target genes. However, the function and related mechanism of miRNA-497 on EC tumorigenesis remain uncertain. This study first demonstrated that the expression levels of miR-497 in esophageal cancer specimens and cells were down-regulated. Forced expression of miR-497 inhibited cell proliferation, tube formation and migration in EC cells. To further investigate the potential molecular mechanism of miR-497 suppression in regulating EC, we found that miR-497 directly binds to the 3'-untranslational region of QKI, miR-497 overexpression suppressed QKI expression. We further found that overexpression of miR-497 enhanced the effect of chemotherapy in EC cell lines, and prevented the tumor growth of EC in vivo. Our findings indicated that miR-497 suppression increased QKI expression and therapeutic resistance of esophageal cancer, which is likely to be a biomarker of EC progression and potential therapeutic target.

Long non-coding RNAs: an overview on miRNA sponging and its co-regulation in lung cancer

Lung cancer is the most devastating cause of death among all cancers worldwide, and non-small cell lung cancer (NSCLC) accounts for 80% of all the lung cancer cases. Beyond common genetic research and epigenomic studies, the extraordinary investigations of non-coding RNAs have provided insights into the molecular basis of cancer. Existing evidence from various cancer models highlights that the regulation of non-coding RNAs is crucial and that their deregulation may be a common reason for the development and progression of cancer, and competition of cancer therapeutics. Non-coding RNAs, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are increasingly recognized as potential cancer biomarkers for early detection and application of therapeutic strategies. The miRNAs have gained importance as master regulators of target mRNAs by negatively regulating their expression. The lncRNAs function as both tumor suppressors and oncogenes, and also compete with miRNAs that influence the translational inhibition processes. This review addresses the role of lncRNAs in lung cancer development, highlights their mechanisms of action, and provides an overview of the impact of lncRNAs on lung cancer survival and progression via miRNA sponging. The improved understanding of lung cancer mechanisms has opened opportunities to analyze molecular markers and their potential therapeutics.

Bone Marrow Mesenchymal Stem Cells (BMSCs) Retard the Aggressive Migrating and Invading Activity of Non-Small Cell Lung Cancer Cells

Non-small cell lung cancer (NSCLC) is a common malignancy worldwide. miR-119-3p is down regulated in many cancers. Nonetheless, the modulatory mechanism of bone marrow mesenchymal stem cells (BMSCs) in NSCLC is unclear. Our research aims to dissect the activity of BMSCs on NSCLC and underlying mechanisms. After isolation and identification, BMSCs were co-cultured with NSCLC cells, which were transfected with miR-119-3p mimics followed by analysis of expression of miR-119-3p and tumor aggressiveness-related proteins, cell invasion/migration and survival. A significantly reduced miR-119-3p level was found in NSCLC cell lines. miR-119-3p mimics inhibited the proliferative, migrating and invasive behaviors of NSCLC cells. Co-culture with BMSCs enhanced miR-119-3p expression in NSCLC cells, thereby suppressing NSCLC cell biological behaviors. Simultaneously, the EMT process was markedly restrained, as indicated by an elevated level of E-cadherin but diminished levels of Vimetnin, N-cadherin and Snail. In conclusion, BMSCs can interfere with the EMT process of NSCLC via up-regulatingmiR-119-3p, thereby retarding the aggressive migration and invasive capability of NSCLC cells.

LncRNA EBLN3P attributes methotrexate resistance in osteosarcoma cells through miR-200a-3p/O-GlcNAc transferase pathway

BACKGROUND

Osteosarcoma is highly malignant. The migration, invasion, and chemoresistance contribute to poor prognosis of osteosarcoma. Research reported that endogenous bornavirus-like nucleoprotein 3 pseudogene (EBLN3P) promotes the progression of osteosarcoma.

METHODS

In this study, the expression of EBLN3P in osteosarcoma tissue with different methotrexate (MTX) treatment responses was measured. Osteosarcoma cell lines with MTX resistance were constructed, and bioinformatic analysis was performed to explore the potential involved targets and pathways.

RESULTS

Higher EBLN3P was associated with MTX resistance. Downregulation of LncEBLN3P decreased the MTX resistance of osteosarcoma cells by sponging miR-200a-3p, an important microRNA that affects epithelial-mesenchymal transition (EMT). The decreased miR-200a-3p resulted in the upregulation of its target gene O-GlcNAc transferase (OGT), which in turn promoted the EMT process of osteosarcoma cells. Further analysis confirmed that the loss of OGT and over-expression of miR-200a-3p could partly abolish the MTX resistance induced by LncEBLN3P.

CONCLUSION

LncEBLN3P is upregulated in osteosarcoma and increases the MTX resistance in osteosarcoma cells through downregulating miR-200a-3p, which in turn promoted the EMT process of osteosarcoma cells by increasing the OGT.

Loss of exosomal micro-RNA-200b-3p from hypoxia cancer-associated fibroblasts reduces sensitivity to 5-flourouracil in colorectal cancer through targeting high-mobility group box 3

Hypoxia-mediated tumor progression is a major problem in colorectal cancer (CRC). MicroRNA (miR)-200b-3p can attenuate tumorigenesis in CRC, while exosomal miRNAs derived from cancer-associated fibroblasts (CAFs) can promote cancer progression. Nevertheless, the function of exosomal miR-200b-3p derived from CAFs in CRC remains unclear. In this study, CAFs and normal fibroblasts (NFs) were isolated from CRC and adjacent normal tissues. Next, exosomes were isolated from the supernatants of CAFs cultured under normoxia and hypoxia. Cell viability was tested using the cell counting kit-8 assay, and flow cytometry was used to assess cell apoptosis. Cell invasion and migration were evaluated using the transwell assay. Dual-luciferase was used to investigate the relationship between miR-200b-3p and high-mobility group box 3 (HMBG3). Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to determine the miR-200b-3p and HMBG3 level. Our results found that the miR-200b-3p level was sharply reduced in CRC tissues compared to adjacent normal tissues. Additionally, the miR-200b-3p level was reduced in exosomes derived from hypoxic CAFs compared to exosomes derived from CAFs under normoxia. Exosomes derived from hypoxic CAFs weakened the sensitivity of CRC cells to 5-fluorouracil (5-FU) compared to hypoxic CAFs-derived exosomes. However, hypoxic CAFs-derived exosomes with upregulated miR-200b-3p increased the sensitivity of CRC cells to 5-fluorouracil (5-FU) compared to hypoxic CAFs-derived exosomes. In addition, HMBG3 was identified as the downstream target of miR-200b-3p in CRC cells, and its overexpression partially reversed the anti-tumor effect of the miR-200b-3p agomir on CRC via the mediation of the β-catenin/c-Myc axis. Furthermore, compared to exosomes derived from normoxia CAFs, exosomes derived from hypoxic CAFs weakened the therapeutic effects of 5-FU on CRC in vivo via the upregulation of HMGB3 levels. Collectively, the loss of exosomal miR-200b-3p in hypoxia CAFs reduced the sensitivity to 5-FU in CRC by targeting HMGB3. Thus, our research outlines a novel method for the treatment of CRC.

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.

MARCKSL1-2 reverses docetaxel-resistance of lung adenocarcinoma cells by recruiting SUZ12 to suppress HDAC1 and elevate miR-200b

Background

Long non-coding RNAs (lncRNAs) are implicated in the development of multiple cancers. In our previous study, we demonstrated that HDAC1/4-mediated silencing of microRNA-200b (miR-200b) enhances docetaxel (DTX)-resistance of human lung adenocarcinoma (LAD) cells.

Methods and results

Herein, we probed the function of LncRNA MARCKSL1–2 (MARCKSL1-transcript variant 2, NR_052852.1) in DTX resistance of LAD cells. It was found that MARCKSL1–2 expression was markedly reduced in DTX-resistant LAD cells. Through gain- or loss- of function assays, colony formation assay, EdU assay, TUNEL assay, and flow cytometry analysis, we found that MARCKSL1–2 suppressed the growth and DTX resistance of both parental and DTX-resistant LAD cells. Moreover, we found that MARCKSL1–2 functioned in LAD through increasing miR-200b expression and repressing HDAC1. Mechanistically, MARCKSL1–2 recruited the suppressor of zeste 12 (SUZ12) to the promoter of histone deacetylase 1 (HDAC1) to strengthen histone H3 lysine 27 trimethylation (H3K27me3) of HDAC1 promoter, thereby reducing HDAC1 expression. MARCKSL1–2 up-regulated miR-200b by blocking the suppressive effect of HDAC1 on the histone acetylation modification at miR-200b promoter. Furthermore, in vivo analysis using mouse xenograft tumor model supported that overexpression of MARCKSL1–2 attenuated the DTX resistance in LAD tumors.

Conclusions

We confirmed that MARCKSL1–2 alleviated DTX resistance in LAD cells by abolishing the inhibitory effect of HDAC1 on miR-200b via the recruitment of SUZ12. MARCKSL1–2 could be a promising target to improve the chemotherapy of LAD.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12943-022-01605-w.

Potential of the miR-200 Family as a Target for Developing Anti-Cancer Therapeutics

MicroRNAs (miRNAs) are small non-coding RNAs (18–24 nucleotides) that play significant roles in cell proliferation, development, invasion, cancer development, cancer progression, and anti-cancer drug resistance. miRNAs target multiple genes and play diverse roles. miRNAs can bind to the 3′UTR of target genes and inhibit translation or promote the degradation of target genes. miR-200 family miRNAs mostly act as tumor suppressors and are commonly decreased in cancer. The miR-200 family has been reported as a valuable diagnostic and prognostic marker. This review discusses the clinical value of the miR-200 family, focusing on the role of the miR-200 family in the development of cancer and anti-cancer drug resistance. This review also provides an overview of the factors that regulate the expression of the miR-200 family, targets of miR-200 family miRNAs, and the mechanism of anti-cancer drug resistance regulated by the miR-200 family.

Molecular Mechanisms of Chemoresistance Induced by Cisplatin in NSCLC Cancer Therapy

Cancer cells utilise several mechanisms to increase their survival and progression as well as their resistance to anticancer therapy: deregulation of growth regulatory pathways by acquiring grow factor independence, immune system suppression, reducing the expression of antigens activating T lymphocyte cells (mimicry), induction of anti-apoptotic signals to counter the action of drugs, activation of several DNA repair mechanisms and driving the active efflux of drugs from the cell cytoplasm, and epigenetic regulation by microRNAs (miRNAs). Because it is commonly diagnosed late, lung cancer remains a major malignancy with a low five-year survival rate; when diagnosed, the cancer is often highly advanced, and the cancer cells may have acquired drug resistance. This review summarises the main mechanisms involved in cisplatin resistance and interactions between cisplatin-resistant cancer cells and the tumour microenvironment. It also analyses changes in the gene expression profile of cisplatin sensitive vs. cisplatin-resistant non-small cell lung cancer (NSCLC) cellular model using the GSE108214 Gene Expression Omnibus database. It describes a protein-protein interaction network that indicates highly dysregulated TP53, MDM2, and CDKN1A genes as they encode the top networking proteins that may be involved in cisplatin tolerance, these all being upregulated in cisplatin-resistant cells. Furthermore, it illustrates the multifactorial nature of cisplatin resistance by examining the diversity of dysregulated pathways present in cisplatin-resistant NSCLC cells based on KEGG pathway analysis.

Identification of key microRNAs and the underlying molecular mechanism in spinal cord ischemia-reperfusion injury in rats

Spinal cord ischemia-reperfusion injury (SCII) is a pathological process with severe complications such as paraplegia and paralysis. Aberrant miRNA expression is involved in the development of SCII. Differences in the experimenters, filtering conditions, control selection, and sequencing platform may lead to different miRNA expression results. This study systematically analyzes the available SCII miRNA expression data to explore the key differently expressed miRNAs (DEmiRNAs) and the underlying molecular mechanism in SCII. A systematic bioinformatics analysis was performed on 23 representative rat SCII miRNA datasets from PubMed. The target genes of key DEmiRNAs were predicted on miRDB. The DAVID and TFactS databases were utilized for functional enrichment and transcription factor binding analyses. In this study, 19 key DEmiRNAs involved in SCII were identified, 9 of which were upregulated (miR-144-3p, miR-3568, miR-204, miR-30c, miR-34c-3p, miR-155-3p, miR-200b, miR-463, and miR-760-5p) and 10 downregulated (miR-28-5p, miR-21-5p, miR-702-3p, miR-291a-3p, miR-199a-3p, miR-352, miR-743b-3p, miR-125b-2-3p, miR-129-1-3p, and miR-136). KEGG enrichment analysis on the target genes of the upregulated DEmiRNAs revealed that the involved pathways were mainly the cGMP-PKG and cAMP signaling pathways. KEGG enrichment analysis on the target genes of the downregulated DEmiRNAs revealed that the involved pathways were mainly the Chemokine and MAPK signaling pathways. GO enrichment analysis indicated that the target genes of the upregulated DEmiRNAs were markedly enriched in biological processes such as brain development and the positive regulation of transcription from RNA polymerase II promoter. Target genes of the downregulated DEmiRNAs were mainly enriched in biological processes such as intracellular signal transduction and negative regulation of cell proliferation. According to the transcription factor analysis, the four transcription factors, including SP1, GLI1, GLI2, and FOXO3, had important regulatory effects on the target genes of the key DEmiRNAs. Among the upregulated DEmiRNAs, miR-3568 was especially interesting. While SCII causes severe neurological deficits of lower extremities, the anti-miRNA oligonucleotides (AMOs) of miR-3568 improve neurological function. Cleaved caspase-3 and Bax was markedly upregulated in SCII comparing to the sham group, and miR-3568 AMO reduced the upregulation. Bcl-2 expression levels showed a opposite trend as cleaved caspase-3. The expression of GATA6, GATA4, and RBPJ decreased after SCII and miR-3568 AMO attenuated this upregulation. In conclusion, 19 significant DEmiRNAs in the pathogenesis of SCII were identified, and the underlying molecular mechanisms were validated. The DEmiRNAs could serve as potential intervention targets for SCII. Moreover, inhibition of miR-3568 preserved hind limb function after SCII by reducing apoptosis, possibly through regulating GATA6, GATA4, and RBPJ in SCII.

Down-Regulation of miR-7 in Gastric Cancer Is Associated With Elevated LDH-A Expression and Chemoresistance to Cisplatin

MicroRNAs (miRNAs) are dysregulated in the context of many cancer types, making them potentially ideal diagnostic or therapeutic targets in patients in which they are aberrantly expressed. In the present study, we found miR-7 to be downregulated in gastric cancer (GC), and we further determined its expression to be closely linked to GC sensitivity to the chemotherapeutic compound cisplatin. This effect appears to be at least partially attributable to the regulation of LDH-A, which is a miR-7 target gene and expression of LDH-A is negatively correlated with miR-7 expression in primary GC tumor samples. When upregulated, we also determined that miR-7 was able to inhibit the proliferation, colony formation, and glycolysis of GC cells owing to its regulation of LDH-A. Moreover, overexpression of miR-7 render cells more sensitive to cisplatin. Our results thus provide novel evidence that miR-7 is a key mediator of GC growth and chemosensitivity through its regulation of LDH-A, thus potentially highlighting this pathway as a therapeutic target for treating affected patients.