MicroRNA-212 inhibits colorectal cancer cell viability and invasion by directly targeting PIK3R3

MicroRNAs (miRNAs): Novel potential therapeutic targets in colorectal cancer

Colorectal cancer (CRC) is the most common malignant tumor and one of the most lethal malignant tumors in the world. Despite treatment with a combination of surgery, radiotherapy, and/or systemic treatment, including chemotherapy and targeted therapy, the prognosis of patients with advanced CRC remains poor. Therefore, there is an urgent need to explore novel therapeutic strategies and targets for the treatment of CRC. MicroRNAs (miRNAs/miRs) are a class of short noncoding RNAs (approximately 22 nucleotides) involved in posttranscriptional gene expression regulation. The dysregulation of its expression is recognized as a key regulator related to the development, progression and metastasis of CRC. In recent years, a number of miRNAs have been identified as regulators of drug resistance in CRC, and some have gained attention as potential targets to overcome the drug resistance of CRC. In this review, we introduce the miRNAs and the diverse mechanisms of miRNAs in CRC and summarize the potential targeted therapies of CRC based on the miRNAs.

The New Face of a Well-Known Antibiotic: A Review of the Anticancer Activity of Enoxacin and Its Derivatives

Simple Summary

Enoxacin is a second-generation quinolone with promising anticancer activity. In contrast to other members of the quinolone group, it exhibits an extraordinary cytotoxic mechanism of action. Enoxacin enhances RNA interference and promotes microRNA processing, as well as the production of free radicals. Interestingly, apart from its proapoptotic, cell cycle arresting and cytostatic effects, enoxacin manifests a limitation of cancer invasiveness. The underlying mechanisms are the competitive inhibition of vacuolar H⁺-ATPase subunits and c-Jun N-terminal kinase signaling pathway suppression. The newly synthesized enoxacin derivatives have shown a magnified cytotoxic effect with an emphasis on prooxidative, proapoptotic and microRNA interference actions. The mentioned mechanisms seem to contribute to a safer, more selective and more effective anticancer therapy.

Abstract

Enoxacin as a second-generation synthetic quinolone is known for its antibacterial action; however, in recent years there have been studies focusing on its anticancer potential. Interestingly, it turns out that compared to other fluoroquinolones, enoxacin exhibits uncommon cytotoxic properties. Besides its influence on apoptosis, the cell cycle and cell growth, it exhibits a regulatory action on microRNA biogenesis. It was revealed that the molecular targets of the enoxacin-mediated inhibition of osteoclastogenesis are vacuolar H⁺-ATPase subunits and the c-Jun N-terminal kinase signaling pathway, causing a decrease in cell invasiveness. Interestingly, the prooxidative nature of the subjected fluoroquinolone enhanced the cytotoxic effect. Crucial for the anticancer activity were the carboxyl group at the third carbon atom, fluorine at the seventh carbon atom and nitrogen at the eighth position of naphyridine. Modifications of the parent drug improved the induction of oxidative stress, cell cycle arrest and the dysregulation of microRNA. The inhibition of V-ATPase–microfilament binding was also observed. Enoxacin strongly affected various cancer but not normal cells, excluding keratinocytes, which suffered from phototoxicity. It seems to be an underestimated anticancer drug with pleiotropic action. Furthermore, its usage as a safe antibiotic with well-known pharmacokinetics and selectivity will enhance the development of anticancer treatment strategies. This review covers articles published within the years 2000–2021, with a strong focus on the recent years (2016–2021). However, some canonical papers published in twentieth century are also mentioned.

LINC02163 promotes colorectal cancer progression via miR-511-3p/AKT3 axis

Long non-coding RNAs and microRNAs are functional regulators in tumour progression. Herein, we revealed the level LINC02163 was up-regulated in CRC tissues and cell lines, and the expression of LINC02163 negatively correlated with prognosis of CRC patients. Functional experiments demonstrated knockdown of LINC02163 significantly attenuated CRC cells proliferation and metastasis. Mechanism analysis showed miR-511-3p could bind LINC02163 and AKT3, and the expressional level of miR-511-3p negatively correlated with the abundance of LINC02163 and AKT3. Inhibition of LINC02163 suppressed cell proliferation, while transfection of miR-511-3p inhibitor or AKT3 in LINC02163-depletion cells restored cell growth and abolished the cell cycle arrest in G0/G1 phase. Therefore, it was indicated that LINC02163 exerted pro-tumour effect through miR-511-3p/AKT3 axis and was prognostic marker for colorectal cancer.

MicroRNA-212-3p regulates early neurogenesis through the AKT/mTOR pathway by targeting MeCP2

Compelling evidence has implicated role of microRNAs (miRNAs) in neurogenesis. Methyl-CpG Binding Protein 2 (MeCP2) was a key contributor to neurological disease. This study investigated whether miR-212-3p affects early neurogenesis associated with MeCP2. Microarray-based gene expression profiling of neurogenesis was employed to identify differentially expressed genes. Next, miR-212-3p expression in neural progenitor cells (NPCs) was detected using in situ hybridization and immunofluorescence. Effect of miR-212-3p and MeCP2 on cell viability, β-tubulin III expression and the AKT/mammalian target of rapamycin (mTOR) pathway activity was examined with gain- and loss-of-function experiments. In vivo experiments were also performed to verify effects of miR-212-3p on nerve tube development. MiR-212-3p expression was decreased while MeCP2 expression was increased during differentiation of NPCs. MiR-212-3p targets MeCP2 and down-regulates its expression, which resulted in repressed cell differentiation, proliferation as well as blocked AKT/mTOR pathway activation, subsequently early neurogenesis was prevented. Furthermore, overexpression of miR-212-3p inhibited nerve tube development in vivo. Taken together, miR-212-3p could restrain early neurogenesis through the blockade of AKT/mTOR pathway activation by targeting MeCP2, suggesting a promising therapeutic target for neurogenic disorders.

MicroRNA-212-3p Attenuates Neuropathic Pain via Targeting Sodium Voltage-gated Channel Alpha Subunit 3 (NaV 1.3)

Purpose:

To explore the role and potential mechanism of miR-212-3p in neuropathic pain regulation.

Methods:

Adult male rats were used to establish chronic constriction injury (CCI) model to mimic the neuropathic pain. Then, paw withdrawal threshold (PWT) and paw withdrawal thermal latency (PWL) were determined. The concentrations of interleukin 1 beta (IL-1β), interleukin 6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were measured with enzyme-linked immune sorbent assay (ELISA) kit and the expression of miR-212-3p was measured by real time quantitative PCR (RTqPCR). Besides, miR-212-3p agomir was intrathecally injected into CCI rats and the expression of key apoptotic proteins was determined by western blot. Furthermore, dual-luciferase reporter assay was used to determine the binding of miR-212-3p and 3’ untranslated regions (3’UTR) of NaV1.3 and the expression levels of NaV1.3 were measured by western blot and RT-qPCR.

Results:

In the CCI group, the PWT and PWL were significantly decreased and IL-1β, IL-6 and TNF-α were increased. miR-212-3p was decreased in response to CCI. The intrathecal injection of miR-212-3p agomir into CCI rats improved the PWT and PWL, decreased the IL-1β, IL-6 and TNF-α, decreased the expression levels of BCL2 associated X, apoptosis regulator (Bax), cleaved caspase-3 and increased the expression levels of BCL2 apoptosis regulator (Bcl-2). The results of dual--luciferase reporter assay showed that miR-212-3p could directly bind with 3’UTR of NaV1.3. The expression of NaV1.3 was up-regulated in CCI rats who were intrathecally injected with miRctrl, whereas it decreased in CCI rats intrathecally injected with miR-212-3p agomir.

Conclusion:

The expression of miR-212a-3p attenuates neuropathic pain by targeting NaV1.3.

Mechanism of miR-137 regulating migration and invasion of melanoma cells by targeting PIK3R3 gene

OBJECTIVE

To investigate the effect of microRNA-137 (miR-137) on the migration and invasion of melanoma cells and its mechanism.

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the expression of miR-137 in melanoma tissues and cells. miR-137 mimics, phosphoinositide-3-kinase regulatory subunit 3 (PIK3R3) small interfering RNA and corresponding controls were transfected into A375 and WM451 cells by lipofection. The expression of PIK3R3 was examined by qRT-PCR and Western blot analysis. The Trans-well assay was conducted to measure cell migration and invasion. Dual luciferase reporter assay was used to detect the interaction between miR-137 and PIK3R3.

RESULTS

Compared with normal pigmented nevus tissue, miR-137 expression was significantly reduced in melanoma tissues. Compared with keratinous HaCaT cells, the level of miR-137 was significantly decreased in melanoma SK-MEL-1, A375, and WM451 cells. Knockdown of miR-137 significantly reduced the migrated and invasive abilities of melanoma A375 and WM451 cells. Moreover, inhibition of PIK3R3 obviously suppressed the migration and invasion abilities of melanoma A375 and WM451 cells. Luciferase activity assay showed that PIK3R3 was a direct target of miR-137. In addition, overexpression of miR-137-inhibited PIK3R3 expression, while knockdown of miR-137-enhanced PIK3R3 abundance. Restoration of PIK3R3 reversed the regulatory effect of miR-137 on cell migration and invasive in melanoma A375 and WM451 cells.

CONCLUSION

miR-137 inhibited melanoma cell migration and invasion by targeting PIK3R3 gene.

MicroRNA-212 suppresses nonsmall lung cancer invasion and migration by regulating ubiquitin-specific protease-9

MicroRNAs (miRNAs) play crucial roles in various biological processes, including migration, proliferation, differentiation, cell cycling, and apoptosis. Epithelial-mesenchymal transition (EMT) has been shown to be related to the capability of migration and invasion in many tumor cells. In this study, we used wound-healing assay and transwell invasion to analysis the capability of migration and invasion in non-small-cell lung carcinoma (NSCLC), respectively. The expression of ubiquitin-specific protease-9-X-linked (USP9X) and miR-212 messenger RNA (mRNA) was determined by quantitative real-time polymerase chain reaction and Western blot analysis was used to determine the E-cadherin and vimentin expression. Our results showed that miR-212 mimic inhibited cell migration and invasion, while miR-212 inhibitor increased cell migration and invasion. There was no significant difference between WP1130 and miR-212 mimic combined with WP1130 groups. Moreover, WP1130 inhibited the capability of the migration and invasion of NSCLC cells. Western blot analysis displayed that miR-212 mimic upregulated E-cadherin expression and downregulated vimentin expression, while miR-212 inhibitor downregulated E-cadherin and upregulated vimentin expression. These data showed that miR-212 regulated NSCLC cell invasion and migration by regulating USP9X expression. Taken together, these findings indicated that miR-212 regulated NSCLC cells migration and invasion through targeting USP9X involved in EMT.

Downregulation of Lgr6 inhibits proliferation and invasion and increases apoptosis in human colorectal cancer

The aim of the present study was to analyze the role of leucine‑rich repeat‑containing G‑protein coupled receptor 6 (Lgr6) in the proliferation and invasion of colorectal cancer (CRC) cells, and to investigate its possible mechanisms. The expression of Lgr6 in CRC tissues was observed by real time‑quantitative polymerase chain reaction and western blotting. Then cell viability, apoptosis and cell invasion was measured by MTT, flow cytometry or Matrigel‑Transwell system, respectively in CRC cells after transfected with Lgr6 siRNA or Lgr6 vector. Furthermore, the expression of apoptosis‑associated protein and PI3K/AKT signaling (phosphorylated‑PI3K, phosphorylated‑AKT, t‑PI3K, t‑AKT) were measured by real‑time PCR/or western blot analysis. The results demonstrated that the level of Lgr6 was higher in CRC tissues than that in adjacent tissues, and Lgr6 overexpression increased CRC proliferation, and invasion of CRC cells in vitro. Notably, suppressing the expression of Lgr6 in CRC cells increased the expression of B‑cell lymphoma-2 (Bcl‑2)‑associated X protein and caspase‑3, but decreased the expression of Bcl‑2 at the mRNA and protein levels. Lgr6 also had the ability to regulate the phosphoinositide 3‑kinase/AKT signaling pathway. It was concluded that Lgr6 has a tumor‑promoting role in the development of CRC, and may serve as a potential diagnostic and prognostic biomarker for the disease.