Negative regulation of CDC42 expression and cell cycle progression by miR-29a in breast cancer

Apoptosis-targeted gene therapy for non-small cell lung cancer using chitosan-poly-lactic-co-glycolic acid -based nano-delivery system and CASP8 and miRs 29A-B1 and 34A

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related deaths worldwide, with resistance to apoptosis being a major driver of therapeutic resistance and aggressive phenotype. This study aimed to develop a novel gene therapy approach for NSCLC by targeting resistance to apoptosis. Loss of function mutations of caspase 8 (CASP8) and downregulation of microRNAs (miRs) 29A-B1 and 34A were identified as key contributors to resistance to apoptosis in NSCLC. A biodegradable polymeric nano-gene delivery system composed of chitosan-poly-lactic-co-glycolic acid was formulated to deliver initiator CASP8 and miRs 29A-B1 and 34A. The nano-formulation efficiently encapsulated the therapeutic genes effectively internalized into NSCLC cells and induced significant apoptosis. Evaluation of the nano-formulation in A549 tumor spheroids showed a significant increase in apoptosis within the core of the spheroids, suggesting effective penetration into the spheroid structures. We provide a novel nano-formulation that demonstrate therapeutic potential for suicidal gene therapy in NSCLC.

Protective role of naftidrofuryl against methotrexate-induced testicular damage via the amelioration of the p53/miRNA-29a/CDC42 apoptotic pathway, inflammation, and oxidative stress

This study aimed to assess the possible protective effects of naftidrofuryl (Naf) against methotrexate (MTX)-induced testicular toxicity in rats. Male rats were randomly distributed into four groups: control, Naf, MTX, and MTX+Naf groups. MTX administration induced oxidative stress, inflammation, and apoptosis in the testicular tissue, while pretreatment with Naf attenuated these pathways. Naf pretreatment significantly decreased malondialdehyde and interleukin-6 contents, microRNA-29a (miRNA-29a) expression level, and nuclear factor kappa B and p53 immunostaining in the testicular tissues compared to the MTX group. Conversely, it significantly increased Johnsen's score, serum testosterone level, serum total antioxidant capacity, testicular superoxide dismutase activity, testicular catalase activity, and testicular cell division cycle 42 (CDC42) expression compared to the MTX group. In conclusion, Naf exerted a significant protective effect against MTX-induced testicular toxicity via antioxidant and anti-inflammatory mechanisms and modulating the p53/miRNA-29a/CDC42 apoptotic pathway.

The Role of miR-29s in Human Cancers—An Update

MicroRNAs (miRNAs) are small non-coding RNAs that directly bind to the 3’ untranslated region (3’-UTR) of the target mRNAs to inhibit their expression. The miRNA-29s (miR-29s) are suggested to be either tumor suppressors or oncogenic miRNAs that are strongly dysregulated in various types of cancer. Their dysregulation alters the expression of their target genes, thereby exerting influence on different cellular pathways including cell proliferation, apoptosis, migration, and invasion, thereby contributing to carcinogenesis. In the present review, we aimed to provide an overview of the current knowledge on the miR-29s biological network and its functions in cancer, as well as its current and potential applications as a diagnostic and prognostic biomarker and/or a therapeutic target in major types of human cancer.

MiR-29a Increase in Aging May Function as a Compensatory Mechanism Against Cardiac Fibrosis Through SERPINH1 Downregulation

Deregulation of microRNA (miRNA) profile has been reportedly linked to the aging process, which is a dominant risk factor for many pathologies. Among the miRNAs with documented roles in aging-related cardiac diseases, miR-18a, -21a, -22, and -29a were mainly associated with hypertrophy and/or fibrosis; however, their relationship to aging was not fully addressed before. The purpose of this paper was to evaluate the variations in the expression levels of these miRNAs in the aging process. To this aim, multiple organs were harvested from young (2–3-months-old), old (16–18-months-old), and very old (24–25-months-old) mice, and the abundance of the miRNAs was evaluated by quantitative real-time (RT)-PCR. Our studies demonstrated that miR-21a, miR-22, and miR-29a were upregulated in the aged heart. Among them, miR-29a was highly expressed in many other organs, i.e., the brain, the skeletal muscle, the pancreas, and the kidney, and its expression was further upregulated during the natural aging process. Western blot, immunofluorescence, and xCELLigence analyses concurrently indicated that overexpression of miR-29a in the muscle cells decreased the collagen levels as well as cell migration and proliferation. Computational prediction analysis and overexpression studies identified SERPINH1, a specific chaperone of procollagens, as a potential miR-29a target. Corroborating to this, significantly downregulated SERPINH1 levels were found in the skeletal muscle, the heart, the brain, the kidney, and the pancreas harvested from very old animals, thereby indicating the role of the miR-29a-SERPINH1 axis in the aging process. In vitro analysis of miR-29a effects on fibroblast and cardiac muscle cells pointed toward a protective role of miR-29a on aging-related fibrosis, by reducing cell migration and proliferation. In conclusion, our study indicates an adaptive increase of miR-29 in the natural aging process and suggests its role as a transcriptional repressor of SERPINH1, with a potential therapeutic value against adverse matrix remodeling and aging-associated tissue fibrosis.

miRNAs: Critical mediators of breast cancer metastatic programming

MicroRNA mediated aberrant gene regulation has been implicated in several diseases including cancer. Recent research has highlighted the role of epigenetic modulation of the complex process of breast cancer metastasis by miRNAs. miRNAs play a crucial role in the process of metastatic evolution by facilitating alterations in the phenotype of tumor cells and the tumor microenvironment that promote this process. They act as critical determinants of the multi-step progression starting from carcinogenesis all the way to organotropism. In this review, we focus on the current understanding of the compelling role of miRNAs in breast cancer metastasis.

MicroRNA-29a inhibits cell proliferation and arrests cell cycle by modulating p16 methylation in cervical cancer

Cervical cancer is the second most common gynecological malignancy. Accumulating evidence has suggested that microRNAs (miRNAs) are involved in the occurrence and development of cervical cancer. The present study aimed to investigate the function and underlying molecular mechanism of microRNA (miRNA/miR)-29a in cervical cancer. Reverse transcription-quantitative PCR and methylation-specific PCR were used to examine the expression of miR-29a and methylated status of p16 promoter, respectively. Cell Counting Kit-8 analysis and flow cytometry were performed to evaluate cell viability and cycle, respectively. Dual-luciferase reporter assay was performed to verify the interaction between miR-29a and its targets. Western blot analysis was performed to detect the protein levels of DNA methyltransferases (DNMT)3A and DNMT3B. The results demonstrated that miR-29a expression was downregulated in cervical cancer tissues and cells, and negatively correlated with p16 promoter hypermethylation. Furthermore, cell experiments confirmed that miR-29a suppressed cell proliferation and induced cell cycle arrest in HeLa and C-33A cells. Mechanically, miR-29a restored normal methylation pattern of the p16 gene by sponging DNMT3A and DNMT3B. Taken together, the results of the present study demonstrated the epigenetic regulation of tumor suppressor p16 by miR-29a as a unique mechanism, thus providing a rationale for the development of miRNA-based strategies in the treatment of cervical cancer.

miR-29a is a negative regulator of influenza virus infection through targeting of the frizzled 5 receptor

Influenza A virus (IAV) infections result in a large number of deaths and substantial economic losses each year. MicroRNAs repress gene expression and are involved in virus-host interactions. miR-29a is known to have anti-tumor and anti-fibrotic effects. However, the role of miR-29a in IAV infection is unclear. In the present study, we investigated the effect of miR-29a on IAV infection and the mechanisms by which it functions. IAV infection was found to cause decreased miR-29a expression in lung epithelial A549 cells and mouse lungs. Overexpression of miR-29a reduced IAV mRNA and protein levels and progeny virus production in HEK293 and A549 cells. Inhibition of IAV infection by miR-29a was observed with different strains of IAV, including A/PR/8/34, A/WSN/1933, and clinical isolates A/OK/3052/09 and A/OK/309/06 H3N2. Knockout of miR-29a using CRISPR/Cas9 resulted in an increase in viral mRNA and protein levels, confirming that miR-29a suppresses IAV infection. A 3' untranslated region (3'-UTR) reporter assay showed that miR-29a had binding sites in the 3'-UTR of the Wnt-Ca²⁺ signaling receptor frizzled 5 gene, and overexpression of miR-29a reduced the level of the endogenous frizzled 5 protein. Wnt5a treatment of HEK293 and A549 cells enhanced IAV infection. Our results suggest that miR-29a inhibits IAV infection, probably via the frizzled 5 receptor.

MiR-29a inhibits cell proliferation and migration by targeting the CDC42/PAK1 signaling pathway in cervical cancer

Cervical cancer is the second most common gynecological malignancy worldwide and the tumorigenesis mechanisms of cervical cancer are still unclear. This study aimed to reveal the role of miR-29a in cervical cancer. The expression level of miR-29a and CDC42 was measured using qRT-PCR. Cell proliferation, apoptosis, migration, and invasion were detected using colony formation, flow cytometry analysis, wound-healing assay, and Transwell assay, respectively. Luciferase reporter assay was used to determine the binding of miR-29a with CDC42. CDC42/p21-activated kinase 1 (PAK1) pathway-related proteins were measured by western blotting. MiR-29a was downregulated and CDC42 was upregulated in cervical cancer cells. Luciferase reporter assay showed that miR-29a negatively regulated the expression of CDC42 by directly targeting 3'-UTR of CDC42. Cell proliferation, migration, and invasion were markedly inhibited, whereas cell apoptosis was significantly increased in Hela and CaSki cells transfected with miR-29a mimics. These effects were partly recovered by CDC42 overexpression. Protein levels of PAK1, p-PAK1, p-LIMK, and p-cofilin were significantly downregulated by miR-29a mimics, which was reversed by CDC42 overexpression and was increased by the miR-29a inhibitor. MiR-29a inhibited cell proliferation, migration, and invasion, as well as promoted cell apoptosis through repressing the PAK1/LIMK signaling pathway by targeting CDC42 in cervical cancer.

MicroRNA-29 family inhibits rhabdomyosarcoma formation and progression by regulating GEFT function

The microRNA-29 family, which contains mir-29a, mir-29b, and mir-29c, can promote or resist the development of several types of tumors. However, its role in rhabdomyosarcoma (RMS) has not been determined. In this work, we detected the expression of mir-29a/b/c in RMS. Results showed that the tissues and cell lines in RMS were significantly lower than those in muscle and human skeletal muscle cells, and that these cell lines could also inhibit the proliferation, migration, and invasion and induce apoptosis of RMS cells. Dual-luciferase reporter assay and RNA immunoprecipitation verified the direct binding site between mir-29a/b/c and GEFT. Under the combined actions of mir-29a/b/c and GEFT, the former weakened the promoting effect of GEFT on RMS cells. Finally, mir-29a inhibited the tumorigenesis of subcutaneous xenografts in nude mice and inhibited the mRNA and protein expression levels of GEFT in transplanted tumors. These findings proved that mir-29 inhibits the occurrence of RMS and may be a potential molecular target.

Focus on Cdc42 in Breast Cancer: New Insights, Target Therapy Development and Non-Coding RNAs

Breast cancer is the most common malignant tumors in females. Although the conventional treatment has demonstrated a certain effect, some limitations still exist. The Rho guanosine triphosphatase (GTPase) Cdc42 (Cell division control protein 42 homolog) is often upregulated by some cell surface receptors and oncogenes in breast cancer. Cdc42 switches from inactive guanosine diphosphate (GDP)-bound to active GTP-bound though guanine-nucleotide-exchange factors (GEFs), results in activation of signaling cascades that regulate various cellular processes such as cytoskeletal changes, proliferation and polarity establishment. Targeting Cdc42 also provides a strategy for precise breast cancer therapy. In addition, Cdc42 is a potential target for several types of non-coding RNAs including microRNAs and lncRNAs. These non-coding RNAs is extensively involved in Cdc42-induced tumor processes, while many of them are aberrantly expressed. Here, we focus on the role of Cdc42 in cell morphogenesis, proliferation, motility, angiogenesis and survival, introduce the Cdc42-targeted non-coding RNAs, as well as present current development of effective Cdc42-targeted inhibitors in breast cancer.

Regulating Cdc42 and Its Signaling Pathways in Cancer: Small Molecules and MicroRNA as New Treatment Candidates

Despite great improvements in the diagnosis and treatment of neoplasms, metastatic disease is still the leading cause of death in cancer patients, with mortality rates still rising. Given this background, new ways to treat cancer will be important for development of improved cancer control strategies. Cdc42 is a member of the Rho GTPase family and plays an important role in cell-to-cell adhesion, formation of cytoskeletal structures, and cell cycle regulation. It thus influences cellular proliferation, transformation, and homeostasis, as well as the cellular migration and invasion processes underlying tumor formation. Cdc42 acts as a collection point for signal transduction and regulates multiple signaling pathways. Moreover, recent studies show that in most human cancers Cdc42 is abnormally expressed and promoting neoplastic growth and metastasis. Regarding possible new treatments for cancer, miRNA and small molecules targeting Cdc42 and related pathways have been recently found to be effective on cancer. In this review, we analyze the newly recognized regulation mechanisms for Cdc42 and Cdc42-related signal pathways, and particularly new treatments using small molecules and miRNAs to inhibit the abnormal overexpression of Cdc42 that may slow down the metastasis process, improve cancer therapy and lead to novel strategies for development of antineoplastic drugs.

RNA-Sequence Analysis Reveals Differentially Expressed Genes (DEGs) in Patients Exhibiting Different Risks of Tumor Metastasis

Background

Breast cancer is one of the most common malignancies in women. In a previous study, we found that for two patients who had a high risk of lymphatic metastasis, lymphatic metastasis did not occur; whereas, for two patients who had a low risk of lymphatic metastasis, lymphatic metastasis did occur.

Material/Methods

We analyzed the differential gene expressions of these four patients by RNA-sequence. The data (HRNM_T versus HRNM_N, LRYM_T versus LRYM_N, and HRNM_T versus LRYM_T) was then processed using differentially expressed genes (DEGs) analysis, functional analysis for DEGs, and PPI network construct.

Results

For HRNM_T versus HRNM_N, there were 224 DEGs. There were 504 DEGs for LRYM_T versus LRYM_N, and 88 DEGs for LRYM_T versus LRYM_N. For HRNM_T versus HRNM_N, DEGs were up-regulated mainly in the cell cycle, the IL-17 signaling pathway, and the progesterone-mediated oocyte maturation; DEGs were down-regulated mainly in the IL-17 signaling pathway. For LRYM_T versus LRYM_N, DEGs were up-regulated mainly in protein digestion and absorption, and cytokine-cytokine receptor interaction; DEGs were down-regulated mainly in ECM-receptor interaction. For HRNM_T versus LRYM_T, DEGs were up-regulated mainly in the PPAR signaling pathway; DEGs were downregulated mainly in the adipocytokine signaling pathway. The DEGs were screened to construct PPI networks.

Conclusions

The GO and KEGG functional enrichments of HRNM_T versus HRNM_N, and LRYM_T versus LRYM_N were consistent with earlier studies. For HRNM_T versus LRYM_T, DEGs were up-regulated mainly in PPAR signaling; DEGs were down-regulated mainly in the adipocytokine pathway.