MiR-34b-3 and miR-449a inhibit malignant progression of nasopharyngeal carcinoma by targeting lactate dehydrogenase A

miR-449a: A Promising Biomarker and Therapeutic Target in Cancer and Other Diseases

In the regulation of gene expression, epigenetic factors like non-coding RNAs (ncRNAs) play an equal role in genetics. The role of microRNAs (miRNAs), which are members of the ncRNA family, in post-transcriptional gene regulation is well-documented and has important implications for both normal and abnormal biological processes, such as angiogenesis, proliferation, survival, and apoptosis. The purpose of this study was to synthesize previous research on miR-449a by analyzing published results from various databases, as there have been a number of investigations on miR-449's potential involvement in the development of human disorders. Based on our findings, miR-449 is strongly dysregulated in a wide range of diseases, from various cancers to cardiovascular diseases, cognitive impairments, and respiratory diseases, and it may play a pivotal role in the development of these problems. In addition, miR-449a functions as a crucial regulator of the expression of several well-known genes, including E2F-3, BCL2, NOTCH1, and SOX4. This, in turn, modulates various pathways and processes related to cancer, including Notch, PI3K, and TGF-β, and contributes to the improvement of cancer drug sensitivity. Curiously, abnormalities in the expression of this miRNA may serve as diagnostic or prognostic indicators for distinguishing between healthy people and patients or to evaluate the survival rates for specific disorders. This article provides a synopsis of the current understanding of miR-449a's role in human disease development through its regulation of gene expression and the biological processes related to these genes and their linked processes. In addition, we have covered the topic of miR-449a's potential as a clinical feature (diagnosis and prognosis) indicator for a range of disorders, both neoplastic and non-neoplastic. In general, our goal was to gain a thorough comprehension of the numerous functions of miR-449a in different disorders.

The multiple roles of LDH in cancer

High serum lactate dehydrogenase (LDH) levels are typically associated with a poor prognosis in many cancer types. Even the most effective drugs, which have radically improved outcomes in patients with melanoma over the past decade, provide only marginal benefit to those with high serum LDH levels. When viewed separately from the oncological, biochemical, biological and immunological perspectives, serum LDH is often interpreted in very different ways. Oncologists usually see high serum LDH only as a robust biomarker of a poor prognosis, and biochemists are aware of the complexity of the various LDH isoforms and of their key roles in cancer metabolism, whereas LDH is typically considered to be oncogenic and/or immunosuppressive by cancer biologists and immunologists. Integrating these various viewpoints shows that the regulation of the five LDH isoforms, and their enzymatic and non-enzymatic functions is closely related to key oncological processes. In this Review, we highlight that serum LDH is far more than a simple indicator of tumour burden; it is a complex biomarker associated with the activation of several oncogenic signalling pathways as well as with the metabolic activity, invasiveness and immunogenicity of many tumours, and constitutes an extremely attractive target for cancer therapy.

Prognostic impact of miR-34b/c DNA methylation, gene expression, and promoter polymorphism in HPV-negative oral squamous cell carcinomas

Micro RNAs (miRNAs) have a key role in gene expression regulation in cancer. The aim of the current study is to evaluate the prognostic value of miR-34b/c promoter hypermethylation, gene expression, and polymorphism in HPV-negative oral squamous cell carcinomas (OSCC). MiR-34b/c promoter hypermethylation and pre-miR-34b/c polymorphism rs4938723 were evaluated in tumor tissues of 148 patients, and miR-34b expression in 123 HPV-negative OSCC. For risk assessment, the control group was comprised of 175 healthy individuals. MiR-34b/c promoter hypermethylation was determined by methylation-specific PCR. Gene expression, genotyping and HPV screening was assessed by Q-PCR. The data from our hospital cohort indicated that miR-34b/c DNA methylation was associated with nodal status (p = 0.048), and predicted the shorter overall survival of HPV-negative OSCC patients (p = 0.008). Down-regulated miR-34b/c expression was associated with smoking (p = 0.047), alcohol use (p = 0.009), stage (p = 0.025), recurrences (p = 0.000), and a poor survival (p = 0.00029). Median values of miR-34b expression were significantly lower in advanced stages III/IV as opposed to stage I/II, p = 0.006, and in nodal positive vs negative patients (p = 0.045). TCGA data also indicated that tumors with stage I-III expressed significantly higher levels of miR-34b, compared to tumors with stage IV (p = 0.035), Low miR-34b/c expression was associated with poor survival in smokers (p = 0.001) and patients with tongue carcinomas (p = 0.00003), and TCGA analysis confirmed these findings although miR-34b expression and miR-34b/c methylation were not associated with survival outcome in the whole TCGA cohort. A significant negative miR-34b/c expression-methylation correlation was observed in our hospital cohort (p = 0.017) and in TCGA cohort. Pre-miR-34b/c polymorphism was not associated with oral cancer risk. Our findings indicate that miR-34b/c hypermethylation and low miR-34b expression could promote the progression and predict the poor prognosis for HPV-negative OSCC, which suggests miR-34b/c as a promising biomarker and therapeutic target for OSCC in the future.

miRNAs as Biomarkers for Diagnosing and Predicting Survival of Head and Neck Squamous Cell Carcinoma Patients

Simple Summary

Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer worldwide. It arises from the epithelium of the upper aerodigestive tract. Increasing evidence suggests that there is a significant role of microRNAs in HNSCC formation and progression. The aim of this study was to explore and compare the expression of HNSCC related miRNAs in tumor vs neighboring healthy tissue of HNSCC patients with tumors located in either the oral cavity, oropharynx, or larynx. Our results demonstrated that expression of these miRNAs was significantly different not only between healthy and tumor tissues, but also among tumor locations. Further analysis indicated that microRNA expression could be used to distinguish between tumor and healthy tissues, and prognose the overall survival of patients.

Abstract

Head and Neck Squamous Cell Carcinoma (HNSCC) is the sixth most common cancer worldwide. These tumors originate from epithelial cells of the upper aerodigestive tract. HNSCC tumors in different regions can have significantly different molecular characteristics. While many microRNAs (miRNAs) have been found to be involved in the regulation of the carcinogenesis and pathogenesis of HNSCC, new HNSCC related miRNAs are still being discovered. The aim of this study was to explore potential miRNA biomarkers that can be used to diagnose HNSCC and prognose survival of HNSCC patients. For this purpose, we chose a panel of 12 miRNAs: miR-146a-5p, miR-449a, miR-126-5p, miR-34a-5p, miR-34b-5p, miR-34c-5p, miR-217-5p, miR-378c, miR-6510-3p, miR-96-5p, miR-149-5p, and miR-133a-5p. Expression of these miRNAs was measured in tumor tissue and neighboring healthy tissue collected from patients diagnosed with HNSCC (n = 79) in either the oral cavity, oropharynx, or larynx. We observed a pattern of differentially expressed miRNAs at each of these cancer locations. Our study showed that some of these miRNAs, separately or in combination, could serve as biomarkers distinguishing between healthy and tumor tissue, and their expression correlated with patients’ overall survival.

Metabolic Reprogramming in Cancer: Role of HPV 16 Variants

Metabolic reprogramming is considered one of the hallmarks in cancer and is characterized by increased glycolysis and lactate production, even in the presence of oxygen, which leads the cancer cells to a process called “aerobic glycolysis” or “Warburg effect”. The E6 and E7 oncoproteins of human papillomavirus 16 (HPV 16) favor the Warburg effect through their interaction with a molecule that regulates cellular metabolism, such as p53, retinoblastoma protein (pRb), c-Myc, and hypoxia inducible factor 1α (HIF-1α). Besides, the impact of the E6 and E7 variants of HPV 16 on metabolic reprogramming through proteins such as HIF-1α may be related to their oncogenicity by favoring cellular metabolism modifications to satisfy the energy demands necessary for viral persistence and cancer development. This review will discuss the role of HPV 16 E6 and E7 variants in metabolic reprogramming and their contribution to developing and preserving the malignant phenotype of cancers associated with HPV 16 infection.

Construction and Analysis of lncRNA-Mediated ceRNA Network in Nasopharyngeal Carcinoma Based on Weighted Correlation Network Analysis

Increasing evidence indicated that aberrant expression of long noncoding RNAs (lncRNAs) are involved in tumorigenesis of nasopharyngeal carcinoma (NPC). The purpose of this study was to construct a lncRNA-mediated ceRNA network based on weighted correlation network analysis (WGCNA). First, modules with highly correlated genes were identified from GSE102349 via WGCNA, and the preservation of the modules was evaluated by GSE68799. Then, the differentially expressed lncRNAs and mRNAs identified from GSE12452 which belonged to the same WGCNA modules and the differentially expressed miRNAs identified from GSE32960 were used to construct a ceRNA network. The prognostic value of the network was evaluated by survival analysis. Furthermore, a risk score model for predicting progression-free survival (PFS) of NPC patients was established via LASSO-penalized Cox regression, and the differences in the expression of the lncRNAs between high- and low-risk groups were investigated. Finally, 14 stable modules were identified, and a ceRNA network composed of 11 lncRNAs, 15 miRNAs, and 40 mRNAs was established. The lncRNAs and mRNAs in the network belonged to the turquoise and salmon modules. Survival analysis indicated that ZNF667-AS1, LDHA, LMNB2, TPI1, UNG, and hsa-miR-142-3p were significantly correlated with the prognosis of NPC. Gene set enrichment analysis indicated that the upregulation of ZNF667-AS1 was associated with some immune-related pathways. Besides, a risk score model consisting of 12 genes was constructed and showed a good performance in predicting PFS for NPC patients. Among the 11 lncRNAs in the ceRNA network, SNHG16, SNHG17, and THAP9-AS1 were upregulated in the high-risk group of NPC, while ZNF667-AS1 was downregulated in the high-risk group of NPC. These results will promote our understanding of the crosstalk among lncRNAs, miRNAs, and mRNAs in the tumorigenesis and progression of NPC.

Regulation of Glycolysis by Non-coding RNAs in Cancer: Switching on the Warburg Effect

The “Warburg effect” describes the reprogramming of glucose metabolism away from oxidative phosphorylation toward aerobic glycolysis, and it is one of the hallmarks of cancer cells. Several factors can be involved in this process, but in this review, the roles of non-coding RNAs (ncRNAs) are highlighted in several types of human cancer. ncRNAs, including microRNAs, long non-coding RNAs, and circular RNAs, can all affect metabolic enzymes and transcription factors to promote glycolysis and modulate glucose metabolism to enhance the progression of tumors. In particular, the 5′-AMP-activated protein kinase (AMPK) and the phosphatidylinositol 3-kinase (PI3K)/AKT/mammalian target of rapamycin (mTOR) pathways are associated with alterations in ncRNAs. A better understanding of the roles of ncRNAs in the Warburg effect could ultimately lead to new therapeutic approaches for suppressing cancer.

MicroRNAs: Biogenesis, Functions and Potential Biomarkers for Early Screening, Prognosis and Therapeutic Molecular Monitoring of Nasopharyngeal Carcinoma

According to reports published, the aberrant expression of microRNAs (miRNAs), a class of 19–25 nucleotide-long small non-coding RNAs, is responsible for human cancers, including nasopharyngeal cancer (NPC). The dysregulation of miRNAs that act either as a tumor suppressor or oncogene, leading to a wide range of NPC pathogenesis pathways, includes the proliferation, invasion, migration as well as the metastasis of NPC cells. This article reviews and highlights recent advances in the studies of miRNAs in NPC, with a specific demonstration of the functions of miRNA, especially circulating miRNAs, in the pathway of NPC pathogenesis. Additionally, the possible use of miRNAs as early screening and prognostic biomarkers and for therapeutic molecular monitoring has been extensively studied.

Role of miR-96/EVI1/miR-449a Axis in the Nasopharyngeal Carcinoma Cell Migration and Tumor Sphere Formation

The Wnt signaling pathway is one of the major signaling pathways used by cancer stem cells (CSC). Ecotropic Viral Integration Site 1 (EVI1) has recently been shown to regulate oncogenic development of tumor cells by interacting with multiple signaling pathways, including the Wnt signaling. In the present study, we found that the Wnt modulator ICG-001 could inhibit the expression of EVI1 in nasopharyngeal carcinoma (NPC) cells. Results from loss-of-function and gain-of-function studies revealed that EVI1 expression positively regulated both NPC cell migration and growth of CSC-enriched tumor spheres. Subsequent studies indicated ICG-001 inhibited EVI1 expression via upregulated expression of miR-96. Results from EVI1 3′UTR luciferase reporter assay confirmed that EVI1 is a direct target of miR-96. Further mechanistic studies revealed that ICG-001, overexpression of miR-96, or knockdown of EVI1 expression could restore the expression of miR-449a. The suppressive effect of miR-449a on the cell migration and tumor sphere formation was confirmed in NPC cells. Taken together, the miR-96/EVI1/miR-449a axis is a novel pathway involved in ICG-001-mediated inhibition of NPC cell migration and growth of the tumor spheres.

H19/miR-675-5p Targeting SFN Enhances the Invasion and Metastasis of Nasalpharyngeal Cancer Cells

AIMS

The aim is to study the role of miR-675-5p coded by long non-coding RNA H19 in the development of Nasopharyngeal Cancer (NPC) and whether miR-675-5p regulates the invasion and metastasis of NPC through targeting SFN (14-3-3σ). The study further validated the relationship between H19, miR-675-5p and SFN in NPC and their relationship with the invasion and metastasis of NPC.

METHODS

Western blot was used to detect the expression of 14-3-3σ protein in immortalized normal nasopharyngeal epithelial cells NP69 and different metastatic potential NPC cells, 6-10B and 5-8F. At the same time, to find out the relationship between 14-3-3σ protein and the expression of H19 and miR-675-5p, the expression of H19 and miR-675-5p in normal nasopharynx epithelial cells NP69 and varied nasopharyngeal carcinoma cells 6-10B and 5-8F were quantified by real-time PCR. MiR-675-5p mimic and inhibitor were transfected into NPC 6-10B to over-express and down-express miR-675-5p; miR-675-5p mimic negative control and inhibitor negative control were transfected into NPC 6-10B as control groups. The effect of over-expression and down-expression by miR-675-5p on the expression of 14-3-3σ protein was detected by Western blotting. The 3'-UTR segments of SFN, containing miR-675-5p binding sites were amplified by PCR and the luciferase activity in the transfected cells was assayed to detect whether SFN is the direct target of miR-675-5p. Transwell and scratch assays were used to verify the changes in NPC invasion and metastasis ability of mimics and inhibitors transfected with miR-675-5p.

RESULTS

The expression of 14-3-3σ protein in normal nasopharynx epithelial cells NP69 is significantly higher than in varied nasopharyngeal carcinoma cells, 6-10B and 5-8F (P<0.05), and the 14-3-3σ protein levels in low-metastatic nasopharyngeal carcinoma cell 6-10B is higher than in high-metastatic nasopharyngeal carcinoma cell 5-8F. The expression of H19 and miR-675-5p are significantly higher in NPC cells than in NP69 cell (P<0.05). The expression of H19 and miR-675-5p in high-Metastatic nasopharyngeal carcinoma cell 5-8F was higher than in low-Metastatic nasopharyngeal carcinoma cell 6-10B. The expression of 14-3-3σ protein in miR-675-5p mimic cells was significantly lower than in mimic NC (negative control) group and blank control group. However, compared with the blank control group, mimic NC showed no significant difference in 14-3-3σ protein between the two groups. The miR-675-5p inhibitor group was significantly higher than the inhibitor NC group and the blank control group (p<0.05), but there was no significant difference in the expression of 14-3-3σ protein in the inhibitor NC group and the blank control group (p>0.05). Dual-luciferase reporter assay system shows the 3'-UTR segments of SFN containing miR-675-5p binding sites. SFN was the target gene of miR-675-5p.

CONCLUSION

14-3-3σ is downregulated in NPC and is involved in the development of NPC. H19 and miR- 675-5p are upregulated in NPC, which is related to the development of NPC. The over-expression of miR- 675-5p inhibits the expression of 14-3-3σ protein. SFN is the target gene of miR-675-5p. MiR-675-5p targets SFN, downregulates its protein expression and promotes the invasion and metastasis of NPC.

CD38 is involved in cell energy metabolism via activating the PI3K/AKT/mTOR signaling pathway in cervical cancer cells

In contrast to normal cells, cancer cells typically undergo metabolic reprogramming. Studies have shown that oncogenes play an important role in this metabolic reprogramming. CD38 is a multifunctional transmembrane protein that is expressed abnormally in a variety of tumor types. To investigate the effect and possible mechanism of CD38 in cervical cancer cells and to provide a new therapeutic target for the treatment of cervical cancer, the present study identified that CD38 is involved in regulating cell metabolism in cervical cancer cells. Liquid chromatography‑tandem mass spectrometry and bioinformatic analyses revealed that differentially abundant proteins in CD38‑overexpressed cervical cancer cells (CaSki‑CD38 and HeLa‑CD38) are predominantly involved in glycolytic pathways, oxidative phosphorylation and the NAD/NADH metabolic process. Further experiments using an ATP test kit and lactate test kit revealed that CD38 promotes glucose consumption, increases lactate accumulation and increases ATP production. In addition, CD38 increases the phosphorylation of phosphatidylserine/threonine kinase (AKT), mechanistic target of rapamycin (mTOR) and phosphatidylinositol‑4,5‑bisphosphate 3‑kinase (PI3K), which play a key role in tumor metabolism. Furthermore, it was found that the energy metabolism of cervical cancer cells was inhibited following treatment with the mTOR inhibitor rapamycin. In conclusion, the results of the present study suggested that CD38 regulates the metabolism of cervical cancer cells by regulating the PI3K/AKT/mTOR pathway, which may be a candidate target for the treatment of cervical cancer.

Non-coding RNAs: Key regulators of aerobic glycolysis in breast cancer

Although extensive research progress has been made in breast cancer in recent years, yet the morbidity and mortality rates of breast cancer are rising, making it the major disease that endangers women's health. Energy metabolism reprogramming is featured by a state termed "aerobic glycolysis" or the Warburg effect that glycolysis is preferred even under aerobic conditions in neoplastic diseases. Widely acknowledged as an emerging hallmark in cancers, this metabolic switch shows a sophisticated role in the pathogenesis of breast cancer. The regulating effect of non-coding RNAs (ncRNAs) composed of microRNAs, long non-coding RNAs and circular RNAs is closely related to the glycolysis in breast cancer. Therefore, understand the mechanisms of ncRNAs of aerobic glycolysis in breast cancer may provide new strategy for the disease.

Multiple Targets of the Canonical WNT/β-Catenin Signaling in Cancers

Canonical WNT/β-catenin signaling is involved in most of the mechanisms that lead to the formation and development of cancer cells. It plays a central role in three cyclic processes, which are the cell division cycle, the immune cycle, and circadian rhythms. When the canonical WNT pathway is upregulated as in cancers, the increase in β-catenin in the nucleus leads to activation of the expression of numerous genes, in particular CYCLIN D1 and cMYC, where the former influences the G1 phase of the cell division cycle, and the latter, the S phase. Every stage of the immune cycle is disrupted by the canonical WNT signaling. In numerous cancers, the dysfunction of the canonical WNT pathway is accompanied by alterations of the circadian genes (CLOCK, BMAL1, PER). Induction of these cyclic phenomena leads to the genesis of thermodynamic mechanisms that operate far from equilibrium, and that have been called “dissipative structures.” Moreover, upregulation of the canonical WNT/β-catenin signaling is important in the myofibroblasts of the cancer stroma. Their differentiation is controlled by the canonical WNT /TGF-β1 signaling. Myofibroblasts present ultraslow contractile properties due to the presence of the non-muscle myosin IIA. Myofibroblats also play a role in the inflammatory processes, often found in cancers and fibrosis processes. Finally, upregulated canonical WNT deviates mitochondrial oxidative phosphorylation toward the Warburg glycolysis metabolism, which is characteristic of cancers. Among all these cancer-generating mechanisms, the upregulated canonical WNT pathway would appear to offer the best hope as a therapeutic target, particularly in the field of immunotherapy.

MiR-34b regulates cervical cancer cell proliferation and apoptosis

Objectives: MiR-34b is a tumour suppressor in different kinds of carcinomas. This study investigated the role of miR-34b in proliferation and apoptosis of cervical cancer. Materials and methods: The expression of miR-34b in 60 cervical cancer patients were quantified by RT-PCR and correlated with their clinicopathological parameters. Besides, there is a significant reverse relationship between miR-43b and TGF-β1 expression in tumour tissues. Cell proliferation and apoptosis was detected by CCK-8 assays and flow cytometry in cell lines transfected with miR-34b mimics. Western blotting, quantitative reverse transcription-PCR (RT-PCR) and luciferase assays were conducted to analyze the regulation of TGF-β1 by miR-34b in cell lines. Results: Here, we found expression of miR-34b to be downregulated in cervical cancer in comparison with the adjacent normal tissues. Expression levels of miR-34b were associated with enhanced malignant potential, such as tumour stage and stromal invasion. The overexpression of miR-34b potently suppressed cell proliferation and induced the apoptosis of cell lines. Conclusions: MiR-34b and TGF-β1 contribute to cervical cancer cell proliferation and apoptosis and are potential targets for cervical cancer therapeutics.

STATegra, a comprehensive multi-omics dataset of B-cell differentiation in mouse

Multi-omics approaches use a diversity of high-throughput technologies to profile the different molecular layers of living cells. Ideally, the integration of this information should result in comprehensive systems models of cellular physiology and regulation. However, most multi-omics projects still include a limited number of molecular assays and there have been very few multi-omic studies that evaluate dynamic processes such as cellular growth, development and adaptation. Hence, we lack formal analysis methods and comprehensive multi-omics datasets that can be leveraged to develop true multi-layered models for dynamic cellular systems. Here we present the STATegra multi-omics dataset that combines measurements from up to 10 different omics technologies applied to the same biological system, namely the well-studied mouse pre-B-cell differentiation. STATegra includes high-throughput measurements of chromatin structure, gene expression, proteomics and metabolomics, and it is complemented with single-cell data. To our knowledge, the STATegra collection is the most diverse multi-omics dataset describing a dynamic biological system.

MiR-34b inhibits the proliferation and promotes apoptosis in colon cancer cells by targeting Wnt/β-catenin signaling pathway

Colon cancer is one of the leading cause of cancer deaths that is severely threatening human health. Several microRNAs (miRNAs) have been found to be associated with the tumor genesis of colon cancer. The present study determined the expression of miR-34b in patients with colon cancer and studied the molecular mechanism of miR-34b in the proliferation and apoptosis of human colon cancer Caco-2 cells in vitro. In colon cancer patients, the expression of miR-34b was decreased in tumor tissues when compared with the adjacent non-tumor tissues. Furthermore, overexpression of miR-34b inhibited proliferation, migration and invasion, while promoted apoptosis in colon cancer cells. The online bioinformatics sites predicted possible regulatory genes of miR-34b and luciferase reporter assay verify that β-catenin was a direct target of miR-34b. Furthermore, miR-34b overexpression significantly decreased the expression of genes associated with Wnt/β-catenin signaling pathway. In conclusion, our results suggest that miR-34b may inhibit migration and invasion of human colon cancer cells by regulating Wnt/β-catenin signaling and miR-34b may be a key target for the treatment and diagnosis of colon cancer.

Correlative analysis of miR-34b and p53 with pathological characteristics of NSCLC

The expression of miR-34b and p53 in non-small cell lung cancer (NSCLC) was investigated to explore its relationship with clinical pathology of NSCLC. Reverse transcription-quantitative PCR (RT-qPCR) method was used to quantitatively analyze miR-34b and p53 in cancer tissue and adjacent paraneoplastic (PTLC) tissue in 54 cases of NSCLC. The relationship between gene expression and clinical pathological data was analyzed. The expression of miR-34b in tumor tissues of NSCLC patients was significantly downregulated in comparison with PTLC. The expression level of miR-34b was negatively correlated with lymph node metastasis. It was positively correlated with the degree of differentiation and negatively correlated with the pathological stage (P<0.05). There was no significant association in the expression of miR-34b with age, sex, histological type, and gross classification (all P>0.05). The expression of p53 in the tumor tissue of NSCLC patients was significantly reduced in comparison with PTLC, and its expression was negatively correlated with the pathological stage, lymph node metastasis, and was positively correlated with the degree of differentiation. The expression of p53 in adenocarcinoma was generally higher than that of squamous cell carcinoma and large cell carcinoma. The expression of p53 in central type cancer was significantly higher than that in peripheral type (P<0.05). The expression of miR-34b and p53 was positively correlated in NSCLC tissues (r=0.797, P<0.001). The high expression of miR-34b and p53 is closely related to the clinical stage and pathological grade of NSCLC. miR-34b and p53 may serve as important tumor markers for NSCLC.

MiR-34b-3p Represses the Multidrug-Chemoresistance of Bladder Cancer Cells by Regulating the CCND2 and P2RY1 Genes

Background

Chemoresistance is a main limitation in chemotherapy for therapeutic cancer. MicroRNA (miRNA) has been indicated in the progression and tumorigenesis of many types of cancer, but the effect of miR-34b-3p in bladder cancer (BCa) cells is still unknown.

Material/Methods

This research compared the multidrug-sensitive (5637) BCa cell line and the multidrug-resistant (EJ) BCa cell line. We found that CCND2 (G1/S-specific cyclin-D2) and P2RY1 (purinergic receptor P2Y1) were the targets of miR-34b-3p, as further validated by qRT-PCR (quantitative real-time polymerase chain reaction) and western blot analysis.

Results

Forced reversal of the levels of miR-34b-3p or CCND2/P2RY1 changed the chemoresistance profiles in both 5637 cells and EJ cells. Further experiments suggested that the CCND2 gene and the P2RY1 gene act in concert to negatively correlate with miR-34b-3p effect on BCa multidrug-chemoresistance.

Conclusions

These results not only reveal new players regulating BCa chemoresistance, but also provide clues for effective chemotherapy for BCa patients.

Warburg effect, lactate dehydrogenase, and radio/chemo-therapy efficacy

The anaerobic metabolism of glucose by cancer cells, even under well-oxygenated conditions, has been documented by Otto Warburg as early as 1927. Micro-environmental hypoxia and intracellular pathways activating the hypoxia-related gene response, shift cancer cell metabolism to anaerobic pathways. In the current review, we focus on a major enzyme involved in anaerobic transformation of pyruvate to lactate, namely lactate dehydrogenase 5 (LDH5). The value of LDH5 as a marker of prognosis of cancer patients, as a predictor of response to radiotherapy (RT) and chemotherapy and, finally, as a major target for cancer treatment and radio-sensitization is reported and discussed. Clinical, translational and experimental data supporting the uniqueness of the LDHA gene and its product LDH5 isoenzyme are summarized and future directions for a metabolic treatment of cancer are highlighted.

Co-expression of AFAP1-AS1 and PD-1 predicts poor prognosis in nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) carries a high potential for metastasis and immune escape, with a great risk of relapse after primary treatment. Through analysis of whole genome expression profiling data in NPC samples, we found that the expression of a long non-coding RNA (lncRNA), actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1), is significantly correlated with the immune escape marker programmed death 1 (PD-1). We therefore assessed the expression of AFAP1-AS1 and PD-1 in a cohort of 96 paraffin-embedded NPC samples and confirmed that AFAP1-AS1 and PD-1 are co-expressed in infiltrating lymphocytes in NPC tissue. Moreover, patients with high expression of AFAP1-AS1 or PD-1 in infiltrating lymphocytes were more prone to distant metastasis, and NPC patients with positive expression of both AFAP1-AS1 and PD-1 had the poorest prognosis. This study suggests that AFAP1-AS1 and PD-1 may be potential therapeutic targets in NPC and that patients with co-expression of AFAP1-AS1 and PD-1 may be ideal candidates for future clinical trials of anti-PD-1 immune therapy.

miR-449a Suppresses Tumor Growth, Migration, and Invasion in Non-Small Cell Lung Cancer by Targeting a HMGB1-Mediated NF-κB Signaling Pathway

MicroRNAs (miRNAs) have been reported to be involved in many human cancers and tumor progression. The dysregulation of miR-449a is found in many types of malignancies and is associated with tumor growth, migration, and invasion. However, its expression and function in non-small cell lung cancer (NSCLC) still remains unclear. In our study, miR-449a was found to be downregulated in both NSCLC tissues and cell lines, and low miR-449a expression was obviously associated with tumor differentiation, TMN stage, and poor overall survival (OS). Moreover, we demonstrated that miR-449a could inhibit tumor proliferation, migration, and invasion in NSCLC. We also confirmed that HMGB1 was a direct target gene of miR-449a in NSCLC with dual-luciferase reporter assay, and upregulation of HMGB1 could reverse the miR-449a-induced suppression of growth, migration, and invasion in NSCLC cells. Last, we found that miR-449a suppressed tumor initiation and development through the NF-κB signaling pathway. These results indicate that miR-449a functions as a tumor suppressor in NSCLC by targeting the HMGB1-mediated NF-κB signaling pathway in NSCLC.

An updated meta-analysis of 23 case-control studies on the association between miR-34b/c polymorphism and cancer risk

The association between in microRNA-34b/c gene rs4938723 polymorphisms and cancer risk remains inconclusive. This meta-analysis was performed to analyze the association between microRNA-34b/c rs4938723 polymorphism and risk for cancer development. In total, 304 studies from PubMed, Embase, Web of Science, Wanfang, and Chinese National Knowledge Infrastructure databases were examined, and 23 studies were included in this meta-analysis. The 23 selected studies involved 10,812 cancer cases and 11,719 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to measure the strength of the association. Our results indicate a significant association between the rs4938723 polymorphism and cancer risk in the overdominant model (P heterogeneity = 0.018, OR = 1.093, and 95% CI = 1.015-1.177 for CT vs. CC/TT). Using a stratified subgroup analysis, rs4938723 polymorphisms were associated with an increased risk for hepatocellular carcinoma, but decreased risk for colorectal, gastric, and esophageal squamous cell cancer. These findings indicate that the rs4938723 gene is a susceptible locus for cancer.

Comprehensive circular RNA profiling reveals the regulatory role of the circRNA-000911/miR-449a pathway in breast carcinogenesis

Circular RNAs (circRNAs) are key regulators in the development and progression of human cancers; however their roles in breast tumorigenesis are not yet well understood. Thus, the present study aimed to investigate the expression profiles and potential modulatory effects of circRNAs on breast carcinogenesis. A human circRNA microarray analysis was performed to screen for abnormally expressed circRNAs in breast cancer tissue and circRNA-000911 was identified as a circRNA which was significantly downregulated in breast cancer cells. Mechanistic investigations suggested that the enhanced expression of circRNA-000911 suppressed cell proliferation, migration and invasion, and promoted the apoptosis of breast cancer cells. By using a biotin-labeled circRNA-000911 probe to perform RNA precipitation in breast cancer cells, we identified miR‑449a as the circRNA‑000911-associated microRNA. Gain- and loss-of-function assays indicated that miR‑449a antagonized circRNA-000911 to regulate breast cancer progression. Subsequently, Notch1 was identified as the functional target of miR‑449a, and the overexpression of circRNA-000911 in breast cancer elevated Notch1 expression. Furthermore, Cignal Signal Transduction Reporter Array and western blot analysis identified nuclear factor-κB (NF-κB) signaling as a functional target of the circRNA-000911/miR‑449a pathway. On the whole, our findings indicate that circRNA-000911 plays an anti-oncogenic role in breast cancer and may thus serve as a promising therapeutic target for patients with breast cancer. Therefore, the overexpression of circRNA-000911 may provide a future direction which may aid in the development of a novel treatment strategy for breast cancer.

Inactivation of HMGCL promotes proliferation and metastasis of nasopharyngeal carcinoma by suppressing oxidative stress

Altered metabolism is considered as a hallmark of cancer. Here we investigated expression of 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) 2 lyase (HMGCL), an essential enzyme in ketogenesis, which produces ketone bodies by the breakdown of fatty acids to supply energy, in nasopharyngeal carcinoma (NPC). The expression of HMGCL was silenced in NPC tissue. Downregulation of HMGCL in NPC was associated with low intracellular β-hydroxybutyrate (β-HB) production, thereby reducing reactive oxygen species (ROS) generation. Ectopic expression of HMGCL restored β-HB level, associated with suppressed proliferation and colony formation of NPC cells in vitro and decreased tumorigenicity in vivo. HMGCL suppressed the migration and invasion of NPC cells in vitro via mesenchymal-epithelial transition. Furthermore, extracellular β-HB supply suppressed the proliferation and migration of NPC cells. Both intra- and extracellular β-HB exerting a suppressive role in NPC depends on ROS generation. Ketogenesis may be impaired in NPC cells due to lack of HMGCL expression, suggesting that it may be a promising target in NPC therapy.

From Prokaryotes to Cancer: Glutamine Flux in Multicellular Units

Bacteria in nature reside in organized communities, termed biofilms, which are composed of multiple individual cells adhering to each other. Similarly, tumors are a multicellular mass with distinct cellular phenotypes. Both tumors and biofilms are considered to be an active interphase between unicellular and multicellular life states. Because both of these units depend on glutamine for growth and survival, we review here glutamine flux within them as a readout for intra- and inter-commensal metabolism. We suggest that the difference between glutamine fluxes in these cellular communities lies mainly in their global multicellular metabolic organization. Both the differences and similarities described here should be taken into account when considering glutamine-targeting therapeutic approaches.

MicroRNA-130a-3p suppresses cell viability, proliferation and invasion in nasopharyngeal carcinoma by inhibiting CXCL12

Incidence of nasopharyngeal carcinoma (NPC) has remained high worldwide, posing a serious health problem. MicroRNAs (miRNAs) are a family of about 20-23 nucleotides small non-coding molecules, which play a significant role in NPC. In this study, we explored the molecular mechanisms of miR-130a-3p in inhibiting viability, proliferation, migration and invasion of NPC cells by suppressing CXCL12. The relative expression of miR-130a-3p and CXCL12 mRNA expression in tissues and cells was measured by qRT-PCR. NPC cell line CNE-2Z was transfected with miR-130a-3p mimics, CXCL12 siRNA, cDNA-CXCL12 and negative control. Western Blot was performed to detect CXCL12 expression. The MTT assay was performed to study cell viability. The colony formation assay was done to test cell growth. Flow cytometry was conducted to analyze cell cycle and apoptosis. The Transwell assay was used to investigate cell migration and invasion. The results found that the up-regulation of miR-130a-3p or down-regulation of CXCL12 could inhibit viability, proliferation, migration and invasion of CNE-2Z cells. Luciferase-reporting system assay was performed to investigate miR-130a-3p could bind to the 3'UTR region of CXCL12 and the overexpression of miR-130a-3p could suppress CXCL12 expression. Collectively, our finding suggested demonstrated that miR-130a-3p could prohibit the progression of NPC by suppressing CXCL12, which might serve as potential therapeutic targets for NPC.

The reverse Warburg effect is likely to be an Achilles' heel of cancer that can be exploited for cancer therapy

Although survival outcomes of cancer patients have been improved dramatically via conventional chemotherapy and targeted therapy over the last decades, there are still some tough clinical challenges that badly needs to be overcome, such as anticancer drug resistance, inevitable recurrences, cancer progression and metastasis. Simultaneously, accumulated evidence demonstrates that aberrant glucose metabolism termed ‘the Warburg effect’ in cancer cell is closely associated with malignant phenotypes. In 2009, a novel ‘two-compartment metabolic coupling’ model, also named ‘the reverse Warburg effect’, was proposed and attracted lots of attention. Based on this new model, we consider whether this new viewpoint can be exploited for improving the existent anti-cancer therapeutic strategies. Our review focuses on the paradigm shift from ‘the Warburg effect’ to ‘the reverse Warburg effect’, the features and molecular mechanisms of ‘the reverse Warburg effect’, and then we discuss its significance in fundamental researches and clinical practice.

Role of tumor microenvironment in tumorigenesis

Tumorigenesis is a complex and dynamic process, consisting of three stages: initiation, progression, and metastasis. Tumors are encircled by extracellular matrix (ECM) and stromal cells, and the physiological state of the tumor microenvironment (TME) is closely connected to every step of tumorigenesis. Evidence suggests that the vital components of the TME are fibroblasts and myofibroblasts, neuroendocrine cells, adipose cells, immune and inflammatory cells, the blood and lymphatic vascular networks, and ECM. This manuscript, based on the current studies of the TME, offers a more comprehensive overview of the primary functions of each component of the TME in cancer initiation, progression, and invasion. The manuscript also includes primary therapeutic targeting markers for each player, which may be helpful in treating tumors.