Loss of BAX by miR-365 Promotes Cutaneous Squamous Cell Carcinoma Progression by Suppressing Apoptosis

Hues of risk: investigating genotoxicity and environmental impacts of azo textile dyes

The textile industry, with its extensive use of dyes and chemicals, stands out as a significant source of water pollution. Exposure to certain textile dyes, such as azo dyes and their breakdown products like aromatic amines, has been associated with health concerns like skin sensitization, allergic reactions, and even cancer in humans. Annually, the worldwide production of synthetic dyes approximates 7 × 107 tons, of which the textile industry accounts for over 10,000 tons. Inefficient dyeing procedures result in the discharge of 15-50% of azo dyes, which do not adequately bind to fibers, into wastewater. This review delves into the genotoxic impact of azo dyes, prevalent in the textile industry, on aquatic ecosystems and human health. Examining different families of textile dye which contain azo group in their structure such as Sudan I and Sudan III Sudan IV, Basic Red 51, Basic Violet 14, Disperse Yellow 7, Congo Red, Acid Red 26, and Acid Blue 113 reveals their carcinogenic potential, which may affect both industrial workers and aquatic life. Genotoxic and carcinogenic characteristics, chromosomal abnormalities, induced physiological and neurobehavioral changes, and disruptions to spermatogenesis are evident, underscoring the harmful effects of these dyes. The review calls for comprehensive investigations into the toxic profile of azo dyes, providing essential insights to safeguard the aquatic ecosystem and human well-being. The importance of effective effluent treatment systems is underscored to mitigate adverse impacts on agricultural lands, water resources, and the environment, particularly in regions heavily reliant on wastewater irrigation for food production.

MicroRNA-124 plays an inhibitory role in cutaneous squamous cell carcinoma cells via targeting SNAI2, an immunotherapy determinant

MicroRNAs (miRs) play multiple roles during cutaneous squamous cell carcinoma (CSCC) progression. Previous studies suggest miR-124 could inhibit cancer development in CSCC.

METHODS

Obtained 63 pairs of CSCC and adjacent tissues for analysis. Cultured HaCaT and two CSCC cell lines (A431 and SCL-1) in DMEM (10 % FBS). Transfected cells using Lipofectamine 2000 with various miR-124 mimics, inhibitors, or Snail family transcriptional repressor 2 (SNAI2) expression plasmid. Performed a series of assays, including real-time quantitative PCR, Western blot, CCK8, wound healing, transwell, and luciferase reporter gene assay, to examine the effects of miR-124 on CSCC cells.

RESULTS

An evident downregulation of miR-124 in CSCC tissues, which was related to advanced disease stage and nodal metastasis. Overexpressing miR-124 could reduce the proliferation, migration, and invasion abilities of CSCC cells. It was verified that miR-124 targets the SNAI2 in CSCC cells. Moreover, ectopic expression of SNAI2 rescued the suppressive effects on CSCC cells induced by miR-124 overexpression. Furthermore, miR-124 increased cell sensitivity to cisplatin. Besides, SNAI2 is a critical factor in the immune-related aspects of CSCC and its modulation may influence the response to immunotherapy.

CONCLUSION

We demonstrate that miR-124 inhibits CSCC progression through downregulating SNAI2, and thus it may be a molecular candidate for treating CSCC in the clinic.

Non-coding RNAs in skin cancers:Biological roles and molecular mechanisms

Cutaneous malignancies, including basal cell carcinoma, cutaneous squamous cell carcinoma, and cutaneous melanoma, are common human tumors. The incidence of cutaneous malignancies is increasing worldwide, and the leading cause of death is malignant invasion and metastasis. The molecular biology of oncogenes has drawn researchers’ attention because of the potential for targeted therapies. Noncoding RNAs, including microRNAs, long noncoding RNAs, and circular RNAs, have been studied extensively in recent years. This review summarizes the aspects of noncoding RNAs related to the metastasis mechanism of skin malignancies. Continuous research may facilitate the identification of new therapeutic targets and help elucidate the mechanism of tumor metastasis, thus providing new opportunities to improve the survival rate of patients with skin malignancies.

Footprints of microRNAs in Cancer Biology

MicroRNAs (miRNAs) are short non-coding RNAs involved in post-transcriptional gene regulation. Over the past years, various studies have demonstrated the role of aberrant miRNA expression in the onset of cancer. The mechanisms by which miRNA exerts its cancer-promoting or inhibitory effects are apparent through the various cancer hallmarks, which include selective proliferative advantage, altered stress response, vascularization, invasion and metastasis, metabolic rewiring, the tumor microenvironment and immune modulation; therefore, this review aims to highlight the association between miRNAs and the various cancer hallmarks by dissecting the mechanisms of miRNA regulation in each hallmark separately. It is hoped that the information presented herein will provide further insights regarding the role of cancer and serve as a guideline to evaluate the potential of microRNAs to be utilized as biomarkers and therapeutic targets on a larger scale in cancer research.

Oh, the Mutations You'll Acquire! A Systematic Overview of Cutaneous Squamous Cell Carcinoma

Nearly two million cases of cutaneous squamous cell carcinoma (cSCC) are diagnosed every year in the United States alone. cSCC is notable for both its prevalence and its propensity for invasion and metastasis. For many patients, surgery is curative. However, patients experiencing immunosuppression or recurrent, advanced, and metastatic disease still face limited therapeutic options and significant mortality. cSCC forms after decades of sun exposure and possesses the highest known mutation rate of all cancers. This mutational burden complicates efforts to identify the primary factors driving cSCC initiation and progression, which in turn hinders the development of targeted therapeutics. In this review, we summarize the mutations and alterations that have been observed in patients’ cSCC tumors, affecting signaling pathways, transcriptional regulators, and the microenvironment. We also highlight novel therapeutic opportunities in development and clinical trials.

Assessment of MicroRNA (miR)-365 Effects on Oral Squamous Carcinoma Cell Line Phenotypes

miR-365 is a microRNA that regulates transcription and has been demonstrated to promote oncogenesis and metastasis in some cancers while suppressing these effects in others. Virtually no information is known about the presence or function of miR-365 in oral cancers. Based upon this information, the primary goal of this project was to evaluate the expression of miR-365 in existing oral cancer cell lines. Five commercially available oral cancer cell lines (SCC4, SCC9, SCC15, SCC25, and CAL27) were obtained and cultured. RNA was then screened by PCR using primers specific for miR-365, as well as matrix metalloproteinase (MMP-2) and a downstream cancer stem cell regulator (NKX2.1), and structural and metabolic standards (beta actin, GAPDH). miR-365 was detected among these oral cancers, and some cells also expressed NKX2.1 and MMP-2, which correlated with miR-365 levels. The relative expression of miR-365, NKX2.1, and MMP-2 RNA was higher than expected. Transfection of miR-365 resulted in a significant increase in proliferation, which was not observed in the negative controls. These data appear to confirm miR-365 expression in oral cancers, which may also be correlated with MMP-2 and NKX2.1 expression. Moreover, the fastest growing oral cancers with the highest viability produced the most miR-365. In addition, miR-365 transfected into cells significantly increased growth, even in normal cells. More research is needed to elucidate the pathways responsible for these observations.

Genome-wide association study of prevalent and persistent cervical high-risk human papillomavirus (HPV) infection

Background

Genetic factors may influence the susceptibility to high-risk (hr) human papillomavirus (HPV) infection and persistence. We conducted the first genome-wide association study (GWAS) to identify variants associated with cervical hrHPV infection and persistence.

Methods

Participants were 517 Nigerian women evaluated at baseline and 6 months follow-up visits for HPV. HPV was characterized using SPF₁₀/LiPA₂₅. hrHPV infection was positive if at least one carcinogenic HPV genotype was detected in a sample provided at the baseline visit and persistent if at least one carcinogenic HPV genotype was detected in each of the samples provided at the baseline and follow-up visits. Genotyping was done using the Illumina Multi-Ethnic Genotyping Array (MEGA) and imputation was done using the African Genome Resources Haplotype Reference Panel. Association analysis was done for hrHPV infection (125 cases/392 controls) and for persistent hrHPV infection (51 cases/355 controls) under additive genetic models adjusted for age, HIV status and the first principal component (PC) of the genotypes.

Results

The mean (±SD) age of the study participants was 38 (±8) years, 48% were HIV negative, 24% were hrHPV positive and 10% had persistent hrHPV infections. No single variant reached genome-wide significance (p < 5 X 10^− 8). The top three variants associated with hrHPV infections were intronic variants clustered in KLF12 (all OR: 7.06, p = 1.43 × 10^− 6). The top variants associated with cervical hrHPV persistence were in DAP (OR: 6.86, p = 7.15 × 10^− 8), NR5A2 (OR: 3.65, p = 2.03 × 10^− 7) and MIR365–2 (OR: 7.71, p = 2.63 × 10^− 7) gene regions.

Conclusions

This exploratory GWAS yielded suggestive candidate risk loci for cervical hrHPV infection and persistence. The identified loci have biological annotation and functional data supporting their role in hrHPV infection and persistence. Given our limited sample size, larger discovery and replication studies are warranted to further characterize the reported associations.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12881-020-01156-1.

Importance of microRNAs in Skin Oncogenesis and Their Suitability as Agents and Targets for Topical Therapy

Skin cancer is the most common cancer worldwide, with rapidly increasing incidence and consistent mortality. Skin cancer encompasses melanoma and non-melanoma skin cancer, which in turn is mainly divided into cutaneous squamous cell carcinoma and basal cell carcinoma. Small noncoding micro-RNAs (miRNAs) regulate protein expression after transcription and play a role in the development and progression of skin cancer. Deregulated expression of miRNAs in skin cancer is associated with cell proliferation, angiogenesis, metastasis, apoptosis, immune response, and drug resistance. Specific patterns of miRNAs in specific skin cancer types can be used as diagnostic markers. For therapeutic purposes, both miRNA and chemically modified variants thereof as well as miRNA antagonists (antagomiRs) or RNA inhibitors may be applied topically. Due to their specific physicochemical properties, physical or chemical diffusion promoters are used with varying degrees of success. There is no question by now that such preparations have a high potential for the treatment of epithelial skin tumors in particular.

The Role of Non-Coding RNAs as Prognostic Factor, Predictor of Drug Response or Resistance and Pharmacological Targets, in the Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (CSCC) is the most common keratinocyte-derived skin cancer in the Caucasian population. Exposure to UV radiations (UVRs) represents the main risk carcinogenesis, causing a considerable accumulation of DNA damage in epidermal keratinocytes with an uncontrolled hyperproliferation and tumor development. The limited and rarely durable response of CSCC to the current therapeutic options has led researchers to look for new therapeutic strategies. Recently, the multi-omics approaches have contributed to the identification and prediction of the key role of non-coding RNAs (ncRNAs), such as microRNAs (miRNAs), circularRNAs (circRNAs) and long non-coding RNAs (lncRNAs) in the regulation of several cellular processes in different tumor types, including CSCC. ncRNAs can modulate transcriptional and post-transcriptional events by interacting either with each other or with DNA and proteins, such as transcription factors and RNA-binding proteins. In this review, the implication of ncRNAs in tumorigenesis and their potential role as diagnostic biomarkers and therapeutic targets in human CSCC are reported.

miR-365 (microRNA): Potential Biomarker in Oral Squamous Cell Carcinoma Exosomes and Extracellular Vesicles

Introduction: miR-365 is a non-coding microRNA that regulates transcription and has been demonstrated to promote oncogenesis and metastasis in some cancers, while suppressing these effects in others. Many microRNAs are produced and then exported extracellularly in exosomes, which are small extracellular vesicles ranging from 30 to 100 nm that are found in eukaryotic fluids and facilitate many cellular functions. Exosomes and extracellular vesicles are produced by many cell types, including oral cancer cells—although no study to date has evaluated miR-365 and oral cancer exosomes or extracellular vesicles. Based on this information, our research question was to evaluate whether oral cancers produce exosomes or extracellular vesicles containing miR-365. Materials and Methods: Two commercially available oral cancer cell lines (SCC25 and CAL27) and a normal oral keratinocyte (OKF4) were grown in serum-free media, supplemented with exosome-depleted fetal bovine serum. Extracellular vesicles and exosomes were then isolated using the Invitrogen total exosome RNA and protein isolation kit for processing using the hsa-miR-365a-5p microRNA qPCR assay kit. Results: RNA was successfully isolated from the exosome-depleted supernatant from each cell line—SCC9, SCC15, SCC25, and CAL27 (oral squamous cell carcinomas) and OKF4 (oral epithelial cell line). Relative concentrations of RNA were similar among each cell line, which were not significantly different, p = 0.233. RNA quality was established by A260:A280 absorbance using a NanoDrop, revealing purity ranging 1.73–1.86. Expression of miR-16 was used to confirm the presence of microRNA from the extracted exosomes and extracellular vesicles. The presence of miR-365 was then confirmed and normalized to miR-16 expression, which demonstrated an increased level of miR-365 in both CAL27 and SCC25. In addition, the normalized relative quantity (RQ) for miR-365 exhibited greater variation among SCC25 (1.382–4.363) than CAL27 cells (1.248–1.536). Conclusions: These results confirm that miR-365 is not only expressed in oral cancer cell lines, but also is subsequently exported into exosomes and extracellular vesicles derived from these cultures. These data may help to contextualize the potential for this microRNA to contribute to the phenotypes and behaviors of oral cancers that express this microRNA. Future research will begin to investigate these potential mechanisms and pathways and to determine if miR-365 may be useful as an oral cancer biomarker for salivary or liquid biopsies.

MiR-664 Protects Against UVB Radiation-Induced HaCaT Cell Damage via Downregulating ARMC8

Background:

MiR-664 has been demonstrated to play an important role in dermal diseases. However, the functions of miR-664 in ultraviolet B (UVB) radiation-induced keratinocytes damage remain to be elucidated.

Objective:

The present study aimed to investigate the molecular mechanisms under the UVB-induced keratinocytes damage and provide translational insights for future therapeutics and UVB protection.

Methods:

HaCaT cells were transfected with miR-664, either alone or combined with UVB irradiation. Levels of messenger RNA and protein were tested by quantitative real-time polymerase chain reaction and Western blot analyses. Cell proliferation, percentage of apoptotic cells, and expression levels of apoptosis-related factors were measured by Cell Counting Kit-8 assay, flow cytometry assay, and Western blot analysis, respectively.

Results:

We found that a significant increase in miR-664 was observed in UVB-induced HaCaT cells. Overexpressed miR-664 promoted cell vitalities and suppressed apoptosis of UVB-induced HaCaT cells. Additionally, the loss/gain of armadillo-repeat-containing protein 8 (ARMC8) rescued/blocked the effects of miR-664 on the proliferation of UVB-induced HaCaT cells.

Conclusions:

Our data demonstrate that miR-664 functions as a protective regulator in UVB-induced HaCaT cells via regulating ARMC8.

miR-365a-3p regulates ADAM10-JAK-STAT signaling to suppress the growth and metastasis of colorectal cancer cells

Purpose: MicroRNAs (miRNAs) are key regulators of the growth and development of a wide range of cancer types such as colorectal cancer (CRC). A number of previously studies have observed that the levels of miR-365a-3p expression are dysregulated in many cancers, but the specific role of this miRNA in CRC and its association with patient prognosis remains unclear. Methods: The expression of miR-365a-3p in CRC tissues and cell lines was detected by Real-time Quantitative polymerase chain reaction (RT-qPCR), while the relationship between miR-365a-3p expression and clinicopathological characteristics was further analyzed. After increasing the expression of miR-365a-3p by plasmid transfection in CRC cells, we further investigated the cell proliferation, invasion and migration by cell counting kit-8 (CCK-8), and Transwell assays. Epithelial-mesenchymal transition (EMT) pathway was also measured by western blotting. In addition, the relationship among miR-365a-3p, ADAM10 and JAK in CRC, was explored by luciferase reporter assay. Results: In the present study, we determined that CRC cells and clinical samples exhibited decreased miR-365a-3p expression, and this was associated with larger tumor size, lymph node metastasis, and local invasion. Patients with lower expression of miR-365a-3p had significantly decreased recurrence-free survival (RFS) and overall survival (OS) relative to those with higher levels of this miRNA. In a multivariate analysis, we confirmed that reduced miR-365a-3p levels were independently predictive of poorer CRC patient outcomes. In a functional study, we determined that elevated miR-365a-3p expression inhibited the ability of CRC cells to proliferate and metastasize in vitro and in vivo. We further identified ADAM10 as a direct miR-365a-3p target, resulting in the suppression of ADAM10 expression in cells expressing this miRNA and ADAM10 levels were in turn closely linked to JAK/STAT signaling. Conclusion: Our study suggested the ability of miR-365a-3p to inhibit the progression of CRC at least in part via suppressing ADAM10 expression and associated JAK/STAT signaling, thus identifying this signaling axis as a possible prognostic and therapeutic target in CRC.

MicroRNA-125b exerts antitumor functions in cutaneous squamous cell carcinoma by targeting the STAT3 pathway

Background

MicroRNA-125b (miR-125b) is downregulated in human cutaneous squamous cell carcinoma (CSCC). However, its function in CSCC has yet to be extensively explored. Here, we analyze the relationship between signal transducer and activator of transcription 3 (STAT3) and miR-125b in CSCC.

Methods

Western blotting and quantitative RT-PCR were used to determine the expression of the miR-125b–STAT3 axis in human CSCC tissues and cell lines. The direct regulatory effect of miR-125b on STAT3 expression was assessed using a luciferase reporter gene assay and RNA immunoprecipitation assay. The MTT assay and flow cytometry were used to determine the role of the miR-125b–STAT3 axis in CSCC cell proliferation and apoptosis.

Results

MiR-125b expression levels were significantly lower in CSCC cell lines and tissues than in normal cell lines and tissues. STAT3 was identified as the direct target of miR-125b. Upregulation of miR-125b and downregulation of STAT3 suppressed cell proliferation and promoted cell apoptosis. Cyclin D1 and Bcl2 were identified as the downstream targets of the miR-125–STAT3 axis.

Conclusions

Our findings indicate that miR-125b acts as a tumor suppressor in CSCC by targeting the STAT3 pathway. This observation increases our understanding of the molecular mechanisms of CSCC. Therapies aimed at activating miR-125b or inhibiting STAT3 signaling should be explored as potential treatments for CSCC.

Long Non-Coding RNA PART1 Exerts Tumor Suppressive Functions in Glioma via Sponging miR-190a-3p and Inactivation of PTEN/AKT Pathway

Background

Glioma is the most commonly diagnosed primary brain tumor. Dysregulation of long non-coding RNA (lncRNA) is associated with initiation and development of various cancer types including glioma.

Methods

The relative expression of lncRNA was analyzed by real time-quantitative polymerase chain reaction (RT-qPCR). Cell counting kit (CCK-8) and flow cytometry analysis were applied to explore the role of prostate androgen-regulated transcript 1 (PART1) in glioma cell lines. Luciferase reporter assay, Western blotting and RT-qPCR were used to investigate the association between PART1, miR-190a-3p and phosphatase and tensin homolog deleted on chromosome ten (PTEN) in glioma cell lines.

Results

In the present study, we elucidated a pivotal role and molecular mechanism of lncRNA PART1 in glioma cell lines. It was found that PART1 was significantly downregulated in glioma tissues compared to normal tissues according to TCGA data and our RT-qPCR results. The cell-based assays showed that PART1 suppressed cell proliferation and triggered cell apoptosis in glioma cell lines. PART1 inactivated PI3K/AKT cascade in glioma cell lines. Transfection of constitutively activated AKT (Myr-AKT) reversed PART1 induced cell apoptosis and cell growth arrest. The bioinformatic analysis suggested that miR-190a-3p might bind to PART1. In the dual luciferase reporter assay, we validated that PART1 directly bound to miR-190a-3p in glioma cell lines. Furthermore, there was a reciprocal repression between PART1 and miR-190-3p. In addition, PART1 upregulated PTEN and inactivated PI3K/AKT pathway in glioma cell lines. Moreover, silencing of PTEN reversed PART1 overexpression induced cell growth arrest and apoptosis. In glioma tissues, the Pearson Correlation analysis showed that there was a strong-positive correlation between PART1 level and PTEN mRNA level.

Conclusion

Taken together, the current study revealed a PART1/miR-190a-3p/PTEN/PI3K/AKT axis in glioma and provided novel insights for understanding the complex lncRNA-miRNA network in glioma.

Emerging approaches to target mitochondrial apoptosis in cancer cells

Apoptosis is a highly conserved programme for removing damaged and unwanted cells. Apoptosis in most cells is coordinated on mitochondria by the Bcl-2 family of proteins. The balance between pro- and anti-apoptotic Bcl-2 family proteins sets a threshold for mitochondrial apoptosis, a balance that is altered during cancer progression. Consequently, avoidance of cell death is an established cancer hallmark. Although there is a general perception that tumour cells are more resistant to apoptosis than their normal counterparts, the realities of cell death regulation in cancer are more nuanced. In this review we discuss how a profound understanding of this control has led to new therapeutic approaches, including the new class of BH3-mimetics, which directly target apoptosis as a vulnerability in cancer. We discuss recent findings that highlight the current limitations in our understanding of apoptosis and how these novel therapeutics work.

MicroRNA Dysregulation in Cutaneous Squamous Cell Carcinoma

Cutaneous squamous cell carcinoma (CSCC) is the second most frequent cancer in humans and it can be locally invasive and metastatic to distant sites. MicroRNAs (miRNAs or miRs) are endogenous, small, non-coding RNAs of 19–25 nucleotides in length, that are involved in regulating gene expression at a post-transcriptional level. MicroRNAs have been implicated in diverse biological functions and diseases. In cancer, miRNAs can proceed either as oncogenic miRNAs (onco-miRs) or as tumor suppressor miRNAs (oncosuppressor-miRs), depending on the pathway in which they are involved. Dysregulation of miRNA expression has been shown in most of the tumors evaluated. MiRNA dysregulation is known to be involved in the development of cutaneous squamous cell carcinoma (CSCC). In this review, we focus on the recent evidence about the role of miRNAs in the development of CSCC and in the prognosis of this form of skin cancer.

PELI3 mediates pro-tumor actions of down-regulated miR-365a-5p in non-small cell lung cancer

Background

To analyze the relative expression of PELI3 and its mechanistic involvement in the non-small cell lung cancer (NSCLC).

Methods

PELI3 expression in NSCLC tissue samples was determined by the immunohistochemistry. The transcripts abundance of PELI3 was measured with real-time PCR. The protein intensity was analyzed by western blot. The overall survival in respect to PELI3 or miR-365a-5p expression was plotted by the Kaplan–Meier’s analysis. Cell growth was determined by colony formation assay. Cell viability was measured by MTT assay. The migration and invasion were evaluated by wound healing and transwell assay respectively. The regulatory effect of miR-365a-5p on PELI3 was interrogated with luciferase reporter assay. The direct binding between miR-365a-5p and PELI3 was analyzed by pulldown assay.

Results

PELI3 was aberrantly up-regulated in NSCLC both in vivo and in vitro. High level of PELI3 associated with poor prognosis. PELI3-deficiency significantly inhibited cell viability, colony formation, migration and invasion. We further identified that miR-365a-5p negatively regulated PELI3 in this disease. Ectopic expression of miR-365a-5p in both A549 and H1299 phenocopied PELI3-deficiency. Meanwhile, PELI3-silencing significantly abolished the pro-tumoral effect elicited by miR-365a-5p inhibition.

Conclusion

Our results highlighted the importance of dysregulated miR-365a-5p-PELI3 signaling axis in NSCLC.

Differential Targeting of c-Maf, Bach-1, and Elmo-1 by microRNA-143 and microRNA-365 Promotes the Intracellular Growth of Mycobacterium tuberculosis in Alternatively IL-4/IL-13 Activated Macrophages

Mycobacterium tuberculosis (Mtb) can subvert the host defense by skewing macrophage activation toward a less microbicidal alternative activated state to avoid classical effector killing functions. Investigating the molecular basis of this evasion mechanism could uncover potential candidates for host directed therapy against tuberculosis (TB). A limited number of miRNAs have recently been shown to regulate host-mycobacterial interactions. Here, we performed time course kinetics experiments on bone marrow-derived macrophages (BMDMs) and human monocyte-derived macrophages (MDMs) alternatively activated with IL-4, IL-13, or a combination of IL-4/IL-13, followed by infection with Mtb clinical Beijing strain HN878. MiR-143 and miR-365 were highly induced in Mtb-infected M(IL-4/IL-13) BMDMs and MDMs. Knockdown of miR-143 and miR-365 using antagomiRs decreased the intracellular growth of Mtb HN878, reduced the production of IL-6 and CCL5 and promoted the apoptotic death of Mtb HN878-infected M(IL-4/IL-13) BMDMs. Computational target prediction identified c-Maf, Bach-1 and Elmo-1 as potential targets for both miR-143 and miR-365. Functional validation using luciferase assay, RNA-pulldown assay and Western blotting revealed that c-Maf and Bach-1 are directly targeted by miR-143 while c-Maf, Bach-1, and Elmo-1 are direct targets of miR-365. Knockdown of c-Maf using GapmeRs promoted intracellular Mtb growth when compared to control treated M(IL-4/IL-13) macrophages. Meanwhile, the blocking of Bach-1 had no effect and blocking Elmo-1 resulted in decreased Mtb growth. Combination treatment of M(IL-4/IL-13) macrophages with miR-143 mimics or miR-365 mimics and c-Maf, Bach-1, or Elmo-1 gene-specific GapmeRs restored Mtb growth in miR-143 mimic-treated groups and enhanced Mtb growth in miR-365 mimics-treated groups, thus suggesting the Mtb growth-promoting activities of miR-143 and miR-365 are mediated at least partially through interaction with c-Maf, Bach-1, and Elmo-1. We further show that knockdown of miR-143 and miR-365 in M(IL-4/IL-13) BMDMs decreased the expression of HO-1 and IL-10 which are known targets of Bach-1 and c-Maf, respectively, with Mtb growth-promoting activities in macrophages. Altogether, our work reports a host detrimental role of miR-143 and miR-365 during Mtb infection and highlights for the first time the role and miRNA-mediated regulation of c-Maf, Bach-1, and Elmo-1 in Mtb-infected M(IL-4/IL-13) macrophages.

MicroRNA-186 promotes cell proliferation and inhibits cell apoptosis in cutaneous squamous cell carcinoma by targeting RETREG1

MicroRNAs (miRs), a class of small non-coding RNAs, have been demonstrated to be involved in the development and progression of human malignancies, including cutaneous squamous cell carcinoma (CSCC). miR-186 serves a suppressive role in certain common types of human cancer; however, its exact function in CSCC has not been reported previously. In the present study, the expression of miR-186 was significantly increased in CSCC tissues compared with adjacent non-tumour tissues. Overexpression of miR-186 significantly promoted CSCC cell proliferation while inhibiting cell apoptosis. Reticulophagy regulator 1 (RETREG1), a gene that is significantly downregulated in CSCC tissues and cell lines, was identified as a novel target of miR-186. In addition, the expression of RETREG1 was inversely correlated with miR-186 expression in CSCC tissues. Furthermore, the expression of RETREG1 was negatively regulated by miR-186 in CSCC cells, and restoration of RETREG1 attenuated the effects of miR-186 on CSCC cells. Taken together, the results of the current study suggest that miR-186 serves an oncogenic role in CSCC and may be used as a potential therapeutic target for the treatment of this disease.

MicroRNA-365 suppresses cell growth and invasion in esophageal squamous cell carcinoma by modulating phosphoserine aminotransferase 1

Background

A number of studies have indicated that expression of miRNA-365 (miR-365) is suppressed in various cancers, suggesting its cancer-suppressive role. In the present investigation, we evaluated the regulation and character of miR-365 in human esophageal squamous cell carcinoma (ESCC).

Patients and methods

The tumor tissues and adjacent nontumor tissue samples were collected from 30 patients having ESCC, and the expression levels of miR-365 were studied by quantitative real-time polymerase chain reaction (PCR). MTT and cell invasion by Matrigel assay were done to study the effect of miR-365 on proliferation and metastasis of ESCC cells. An in vivo tumor model was generated by inoculating ESCC cells subcutaneously into BALB nude mice. A study of various biomarkers such as quantitative polymerase chain reaction (qPCR), luciferase activity assay, and Western blot was done to confirm the targets of miR-365.

Results

In tumor tissues, a significant downregulation of miR-365 was observed versus the nontumor adjacent tissues and ESCC cells versus the selected esophageal endothelial cells. It was observed that higher expression levels of miR-365 inhibited the cell invasion, colony formation, growth in esophageal cancer cell lines in vitro, and tumor development in vivo. The study of biomarkers suggests involvement of phosphoserine aminotransferase 1 (PSAT1) as a favorable target for miR-365, and its abnormal expression inverted the miR-365-arbitrated suppression of invasion, viability, and epithelial-mesenchymal transition in esophageal cancer cells. A negative correlation existed with expression of miR-365 and PSAT1 in human esophageal cancer tissue samples.

Conclusion

The study established that miR-365 exhibits tumor-suppressive action via regulating the levels of PSAT1 and leads to invasion and progressiveness of esophageal cancer.

MicroRNA-340 inhibits squamous cell carcinoma cell proliferation, migration and invasion by downregulating RhoA

BACKGROUND

MicroRNAs are reported to play an important role in tumor growth and metastasis, including squamous cell carcinoma (SCC). Accumulative evidence has revealed that dysregulated miR-340 expression contributed to the carcinogenesis and development of various cancers.

OBJECTIVE

The aim of the current study was to investigate the role and the underlying mechanism of miR-340 in SCC cell proliferation, migration and invasion.

METHODS

Quantitative real-time PCR was performed to examine the expression of miR-340 in SCC tissues and cell lines. The function of miR-340 in SCC was investigated through Cell Counting Kit-8, wound healing, transwell migration and invasion assays. Bioinformatics analysis, luciferase reporter assay, western blotting and immunohistochemical analysis were conducted to predict and confirm the target gene of miR-340.

RESULTS

In the present study, we first found that miR-340 was significantly decreased in both SCC tissues and cell lines. Moreover, ectopic expression of miR-340 remarkably attenuated SCC cell proliferation, migration and invasion, whereas inhibition of endogenous miR-340 promoted SCC cell proliferation, migration and invasion in vitro. Our subsequent bioinformatics analysis and luciferase reporter assay showed that RhoA was a novel direct target of miR-340 in SCC cells, and the knockdown of RhoA expression rescued the effects of miR-340 inhibition on SCC cell proliferation, migration and invasion. More importantly, the expression of RhoA and miR-340 was negatively correlated in SCC tissues.

CONCLUSION

Our findings demonstrate the tumor suppressor role of miR-340 in SCC by directly regulating RhoA. Therefore, restoration of miR-340 expression can be a potential therapeutic approach for SCC treatment.

Colony stimulating factor-1 receptor promotes proliferation, migration and invasion in the human nasopharyngeal carcinoma 6-10B cell line via the phosphoinositide 3-kinase/Akt pathway

The present study aimed to investigate the effects of colony-stimulating factor-1 receptor (CSF-1R) on proliferation, migration and invasion in the human nasopharyngeal carcinoma (NPC) 6-10B cell line, and to investigate the possible underlying mechanisms. Using a lentiviral transfection method, a virus carrying the CSF-1R gene was transfected into 6-10B cells. The expression of CSF-1R was then detected by reverse transcription-quantitative polymerase chain reaction and western blot analysis, and was revealed to be markedly enhanced in 6-10B cells. Subsequently, an MTT assay was performed to assess cell proliferative ability, and flow cytometric analysis was utilized to measure the apoptotic rate of the cells. Wound healing and Transwell assays were also performed to observe cell migration and invasion capabilities. Additionally, western blot analysis was used to detect the protein expression of the proliferation and apoptosis signaling factors cyclin D1, B-cell lymphoma 2, Bcl-2-associated X protein, and phosphorylated and total extracellular protein kinase B (Akt/PKB) in 6-10B cells. The results showed that CSF-1R overexpression promoted the proliferation, migration and invasion of the 6-10B cells. The corresponding mechanism may be associated with activation of the phosphoinositide 3-kinase/Akt pathway, which promotes cell survival and proliferation. These results indicated a potential molecular target for the treatment of NPC.

Inhibitory effect of microRNA-154 targeting WHSC1 on cell proliferation of human skin squamous cell carcinoma through mediating the P53 signaling pathway

OBJECTIVE

Skin squamous cell carcinoma (SCC) is a common, morbid, and frequently lethal malignancy and ranks as the sixth most deadly cancer worldwide. Hence, this study aims to explore the effect of microRNA-154 (miR-154) targeting WHSC1 on proliferation and apoptosis of SCC cells via the P53 signaling pathway.

METHODS

The targeting relationship between WHSC1 and miR-154 was validated using dual-luciferase reporter assay. Normal human epidermal keratinocytes (NHEK) were included, and SCC A431 and SCC-15 cell lines were cultured and transfected with miR-154 mimic, miR-154 inhibitor or siRNA-WHSC1. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were used for the miR-154 expression and levels of WHSC1, P53 signaling pathway- and apoptosis-related genes. MTT assay and flow cytometry were applied to determine the cell viability and apoptosis.

RESULTS

WHSC1 is a target gene of miR-154. MiR-154 negatively regulated WHSC1 expression and inhibited the activation of P53 signaling pathway. In response to miR-154 mimic or siRNA-WHSC1, SCC A431 and SCC-15 cell lines exhibited increased expression of P73, P16 and Bax, decreased expression of WHSC1, P53, c-myc and Bcl-2, as well as attenuated cell viability and enhanced cell apoptosis. The treatment of miR-154 inhibitor reversed the tendency.

CONCLUSION

These results demonstrate that up-regulation of miR-154 inhibits proliferation and induces apoptosis of human skin SCC cells by down-regulating WHSC1 and blocking the P53 signaling pathway.

HOXA9 inhibits HIF-1α-mediated glycolysis through interacting with CRIP2 to repress cutaneous squamous cell carcinoma development

Glycolytic reprogramming is a typical feature of many cancers; however, key regulators of glucose metabolism reengineering are poorly understood, especially in cutaneous squamous cell carcinoma (cSCC). Here, Homeobox A9 (HOXA9), a direct target of onco-miR-365, is identified to be significantly downregulated in cSCC tumors and cell lines. HOXA9 acts as a tumor suppressor and inhibits glycolysis in cSCC in vitro and in vivo by negatively regulating HIF-1α and its downstream glycolytic regulators, HK2, GLUT1 and PDK1. Mechanistic studies show that HOXA9-CRIP2 interaction at glycolytic gene promoters impeds HIF-1α binding, repressing gene expression in trans. Our results reveal a miR-365-HOXA9-HIF-1α regulatory axis that contributes to the enhanced glycolysis in cSCC development and may represent an intervention target for cSCC therapy.

Hypoxia-inducible transcription factor HIF-1α promotes glycolysis allowing cell survival under stress. Here the authors show, using both cell lines and animal models, that in cutaneous squamous cell carcinoma HOXA9 acts as a tumor suppressor and inhibits glycolysis by associating with CRIP2 to repress HIF-1α binding to target genes.