Role of miRNA in cancer diagnosis, prognosis, therapy and regulation of its expression by Epstein-Barr virus and human papillomaviruses: With special reference to oral cancer

Metastasis and cell proliferation inhibition by microRNAs and its potential therapeutic applications in OSCC: A systematic review

BACKGROUND AND AIMS

Oral squamous cell carcinoma (OSCC) is among the most malignant cancers in the world and has a high mortality rate. MicroRNAs (miRNAs) have progressively gained attention due to their roles in the pathogenesis and maintenance of various kinds of cancers, including OSCC. In this research, we carried out a scoping review to analyze the role of miRNA and therapeutic response in OSCC and focus on target axes associated with miRNA that inhibit metastasis and cell proliferation in OSCC.

METHODS

This review adhered to a six-stage methodology framework and PRISMA guidelines. Three databases were systematically searched to find eligible articles until July 2024. Two reviewers conducted publication screening and data extraction independently. 54 articles meeting the predefined inclusion criteria were successfully identified. Quality assessment was done using the QUIN checklist specified for dental in vitro studies.

RESULTS

Studies with different designs reported 53 miRNAs that were experimentally validated to act as therapeutic targets in OSCC in vivo and in vitro studies. The study found that 25 miRNAs were up-regulated in OSCC patients and cell lines, while another 25 were down-regulated. Mir-186 was also found to be up- and down-regulated in two different investigations. The study highlights the potential of six microRNAs (miR-32-5p, miR-195-5p, miR-3529-3p, miR-191, miR-146b-5p, and miR-377-3p) as anti-proliferation, migration, and invasion therapeutics for OSCC treatment. Two miRNAs (miR-302b and miR-18a) are identified as anti-metastatic therapeutics, while four miRNAs (miR-617, miR-23a-3p, miR-105, miR-101) are anti-proliferation therapeutics.

CONCLUSION

The study recommends that restoring the expression of tumor suppressor miRNAs may be a suitable cancer therapy. Utilizing this technology does present certain difficulties, and resolving them will improve the methods for miRNA transfer to target cells. With more research and the resolution of associated issues, miRNA can be employed as an efficient therapeutic method for OSCC.

EBV-encoded miRNAs BHRF1-1 and BART2-5p aggravate post- transplant lymphoproliferative disorder via LZTS2-PI3K-AKT axis

Post-transplant lymphoproliferative disorder (PTLD) is one of the most serious complications after transplantation. Epstein-Barr virus (EBV) is a key pathogenic driver of PTLD. About 80% of PTLD patients are EBV positive. However, the accuracy of preventing and diagnosing EBV-PTLD by monitoring EBV DNA load is limited. Therefore, new diagnostic molecular markers are urgently needed. EBV-encoded miRNAs can regulate a variety of EBV-associated tumors and are expected to be potential diagnostic markers and therapeutic targets. We found BHRF1-1 and BART2-5p were significantly elevated in EBV-PTLD patients, functionally promoting proliferation and inhibiting apoptosis in EBV-PTLD. Mechanistically, we first found that LZTS2 acts as a tumor suppressor gene in EBV-PTLD, and BHRF1-1 and BART2-5p can simultaneously inhibit LZTS2 and activate PI3K-AKT pathway. This study shows that BHRF1-1 and BART2-5p can simultaneously inhibit the expression of tumor suppressor LZTS2, and activate the PI3K-AKT pathway, leading to the occurrence and development of EBV-PTLD. Therefore, BHRF1-1 and BART2-5p are expected to be potential diagnostic markers and therapeutic targets for EBV-PTLD patients.

miR-125b-5p, miR-155-3p, and miR-214-5p and Target E2F2 Gene in Oral Squamous Cell Carcinoma

It is known that E2F2 (E2F transcription factor 2) plays an important role as controller in the cell cycle. This study aimed to analyse the expression of the E2F2 gene and E2F2 protein and demonstrate E2F2 target microRNAs (miRNAs) candidates (miR-125b-5p, miR-155-3p, and miR-214-5p) in oral squamous cell carcinoma tumour and margin samples. The study group consisted 50 patients. The E2F2 gene and miRNAs expression levels were assessed by qPCR, while the E2F2 protein was assessed by ELISA. When analysing the effect of miRNAs expression on E2F2 gene expression and E2F2 protein level, we observed no statistically significant correlations. miR-125b-5p was downregulated, while miR-155-3p, and miR-214-5p were upregulated in tumour samples compared to margin. We observed a difference between the miR-125b-5p expression level in smokers and non-smokers in margin samples. Furthermore, HPV-positive individuals had a significantly higher miR-125b-5p and miR-214-5p expression level compared to HPV-negative patients in tumour samples. The study result showed that the E2F2 gene is not the target for analysed miRNAs in OSCC. Moreover, miR-155-3p and miR-125b-5p could play roles in the pathogenesis of OSCC. A differential expression of the analysed miRNAs was observed in response to tobacco smoke and HPV status.

Silencing LCN2 suppresses oral squamous cell carcinoma progression by reducing EGFR signal activation and recycling

BACKGROUND

EGFR is an important signal involved in tumor growth that can induce tumor metastasis and drug resistance. Exploring targets for effective EGFR regulation is an important topic in current research and drug development. Inhibiting EGFR can effectively inhibit the progression and lymph node metastasis of oral squamous cell carcinoma (OSCC) because OSCC is a type of cancer with high EGFR expression. However, the problem of EGFR drug resistance is particularly prominent, and identifying a new target for EGFR regulation could reveal an effective strategy.

METHODS

We sequenced wild type or EGFR-resistant OSCC cells and samples from OSCC patients with or without lymph node metastasis to find new targets for EGFR regulation to effectively replace the strategy of directly inhibiting EGFR and exert an antitumor effect. We then investigated the effect of LCN2 on OSCC biological abilities in vitro and in vivo through protein expression regulation. Subsequently, we elucidated the regulatory mechanism of LCN2 through mass spectrometry, protein interaction, immunoblotting, and immunofluorescence analyses. As a proof of concept, a reduction-responsive nanoparticle (NP) platform was engineered for effective LCN2 siRNA (siLCN2) delivery, and a tongue orthotopic xenograft model as well as an EGFR-positive patient-derived xenograft (PDX) model were applied to investigate the curative effect of siLCN2.

RESULTS

We identified lipocalin-2 (LCN2), which is upregulated in OSCC metastasis and EGFR resistance. Inhibition of LCN2 expression can effectively inhibit the proliferation and metastasis of OSCC in vitro and in vivo by inhibiting EGFR phosphorylation and downstream signal activation. Mechanistically, LCN2 binds EGFR and enhances the recycling of EGFR, thereby activating the EGFR-MEK-ERK cascade. Inhibition of LCN2 effectively inhibited the activation of EGFR. We translated this finding by systemic delivery of siLCN2 by NPs, which effectively downregulated LCN2 in the tumor tissues, thereby leading to a significant inhibition of the growth and metastasis of xenografts.

CONCLUSIONS

This research indicated that targeting LCN2 could be a promising strategy for the treatment of OSCC.

Exosomal microRNAs: A Diagnostic and Therapeutic Small Bio-molecule in Esophageal Cancer

Esophageal cancer (EC) is one of the major causes of cancer-related death worldwide. EC is usually diagnosed at a late stage, and despite aggressive therapy, the five-year survival rate of patients remains poor. Exosomes play important roles in cancer biology. Indeed, exosomes are implicated in tumor proliferation, angiogenesis, and invasion. They contain bioactive molecules such as lipids, proteins, and non-coding RNAs. Exosome research has recently concentrated on microRNAs, which are tiny noncoding endogenous RNAs that can alter gene expression and are linked to nearly all physiological and pathological processes, including cancer. It is suggested that deregulation of miRNAs results in cancer progression and directly induces tumor initiation. In esophageal cancer, miRNA dysregulation plays an important role in cancer prognosis and patients' responsiveness to therapy, indicating that miRNAs are important in tumorigenesis. In this review, we summarize the impact of exosomal miRNAs on esophageal cancer pathogenesis and their potential applications for EC diagnosis and therapy.

Pathogenesis and prognosis of primary oral squamous cell carcinoma based on microRNAs target genes: a systems biology approach

Oral squamous cell carcinoma (OSCC) is the most prevalent head and neck malignancy, with frequent cervical lymph-node metastasis, leading to a poor prognosis in OSCC patients. The present study aimed to identify potential markers, including microRNAs (miRNAs) and genes, significantly involved in the etiology of early-stage OSCC. Additionally, the main OSCC's dysregulated Gene Ontology annotations and significant signaling pathways were identified. The dataset GSE45238 underwent multivariate statistical analysis in order to distinguish primary OSCC tissues from healthy oral epithelium. Differentially expressed miRNAs (DEMs) with the criteria of p-value < 0.001 and |Log2 fold change| > 1.585 were identified in the two groups, and subsequently, validated targets of DEMs were identified. A protein interaction map was constructed, hub genes were identified, significant modules within the network were illustrated, and significant pathways and biological processes associated with the clusters were demonstrated. Using the GEPI2 database, the hub genes' predictive function was assessed. Compared to the healthy controls, main OSCC had a total of 23 DEMs. In patients with head and neck squamous cell carcinoma (HNSCC), upregulation of CALM1, CYCS, THBS1, MYC, GATA6, and SPRED3 was strongly associated with a poor prognosis. In HNSCC patients, overexpression of PIK3R3, GIGYF1, and BCL2L11 was substantially correlated with a good prognosis. Besides, “proteoglycans in cancer” was the most significant pathway enriched in the primary OSCC. The present study results revealed more possible mechanisms mediating primary OSCC and may be useful in the prognosis of the patients with early-stage OSCC.

miR-195 Inhibits Proliferation and Enhances Apoptosis of OSCC Cells via Targeting TLR4

The aim of this research was to assess the function of microribonucleic acid (miR)-195 in the apoptosis and proliferation of oral squamous cell carcinoma (OSCC) cells as well as its action mechanism. The downstream target protein of miR-195 was predicted using the biological software. A quantitative polymerase chain reaction (qPCR) was implemented to examine the changes in expressions of miR-195 and its target protein toll-like receptor 4 (TLR4) in OSCC cell lines (TSCCA, Tca8223, Tb3.1, and CAL-27) and normal adult human gingival fibroblasts (HGFs), and the relation between their expressions was assessed. The expressions of phosphorylated proteins in nuclear factor-κB (NF-κB) pathway were determined through western blotting. miR-195 was expressed at a noticeably lower level in four OSCC cells than in HGFs, and the lowest level appeared in CAL-27 cells. Compared with miR-195 control, the miR-195 mimic could obviously raise the expression of miR-195. In CAL-27 cells with high expression of miR-195, the proliferation was inhibited and the apoptosis was evidently enhanced. OSCC cells exhibited evidently reduced protein and mRNA expression of TLR4, and miR-195 expression was inversely associated with TLR4 expression. It was uncovered from the dual-luciferase reporter assay that cells with wild-type TLR4 had prominently weakened luciferase activity relative to cells with mutant-type TLR4, revealing that the direct target of miR-195 is TLR4. The NF-κB pathway was impeded in cells that lowly expressed TLR4. miR-195 blocks the NF-κB pathway via inhibiting the expression of TLR4 in OSCC cells, thereby exerting an antitumor effect.

LncRNA HOXD‐AS1 promotes oral squamous cell carcinoma by sponging miR‐203a‐5p

OBJECTIVE

In the present study, we aimed to explore lncRNA HOXD cluster antisense RNA 1 (HOXD-AS1) expression in oral squamous cell carcinoma (OSCC) tissues, its biological roles, and the underlying potential mechanisms in OSCC progression.

MATERIALS AND METHODS

HOXD-AS1 expression in paired OSCC and non-tumor tissues from 60 OSCC patients was determined by RT-qPCR. The effects of HOXD-AS1 and miR-203a-5p overexpression on expression of Annexin A4, a validated target of miR-203a-5p, were analyzed by RT-qPCR and Western blot. The roles of HOXD-AS1, miR-203a-5p, and Annexin A4 in the invasion and migration of OSCC cells were analyzed by Transwell assays.

RESULTS

HOXD-AS1 overexpression in OSCC predicted poor survival. HOXD-AS1 was predicted to interact with miR-203a-5p, but its expression was not significantly correlated with miR-203a-5p. HOXD-AS1 overexpression increased Annexin A4 expression, while miR-203a-5p overexpression decreased Annexin A4 expression in OSCC cells. Transwell assays showed that invasion and migration of OSCC cells were enhanced by HOXD-AS1 and Annexin A4 overexpression but were reduced by miR-203a-5p overexpression. In addition, miR-203a-5p overexpression suppressed the role of HOXD-AS1 in cell movement and Annexin A4 expression.

CONCLUSIONS

HOXD-AS1 may upregulate Annexin A4 by sponging miR-203a-5p in OSCC to promote cancer cell invasion and migration.

Screening and Functional Analysis of Hub MicroRNAs Related to Tumor Development in Colon Cancer

Various microRNAs (miRNAs) are of importance in the development of colon cancer, but most of the mechanisms of the miRNAs are still unclear. In order to clarify the hub miRNAs and their roles in colon cancer development, GSE98406 was used to screen hub miRNAs by bioinformatics analysis. 46 DE-miRNAs (14 were upregulated and 32 were downregulated) and 1738 target genes of DE-miRNAs were ascertained. miRNAs-gene-networks and miRNAs-GO-networks were built to get more knowledge about the function of candidate miRNAs. After validation, three miRNAs (miR-17-5p, miR-182-5p and miR-200a-3p) were recognized to be hub miRNAs associated with the progression of colon cancer. More importantly, the hub miRNAs and the putative targets genes might be new diagnostic and therapeutic targets for colon cancer in the future.

MicroRNA-140-5p inhibits the tumorigenesis of oral squamous cell carcinoma by targeting p21-activated kinase 4

Oral squamous cell carcinoma (OSCC) is a serious global health problem. Recently, accumulating microRNA (miRNA) has emerged as crucial players in the development and progression of carcinomas including OSCC. Our study aimed to further investigate the roles of miR-140-5p in OSCC tumorigenesis and related molecular basis. In this study, OSCC tissues and adjacent normal tissues were isolated from 34 OSCC patients who suffered from surgical resection at our hospital. MiR-140-5p level was measured by reverse-transcription quantitative polymerase chain reaction assay. p21-activated kinase 4 (PAK4) protein level was determined by western blot assay in OSCC cells at 48 h posttransfection or OSCC xenograft tumors at day 35 after OSCC cell injection. The cell proliferative ability was assessed by cell counting kit-8 assay in OSCC cells at 0, 24, 48, 72 h after transfection. Cell apoptosis and cell-cycle analysis was conducted using a flow cytometry in OSCC cells at 48 h after transfection. The interaction between miR-140-5p and PAK4 3'-untranslated region was tested by bioinformatics analysis and luciferase reporter assay in OSCC cells at 48 h after transfection. Mouse xenograft models of OSCC were established to examine the influence of miR-140-5p on OSCC tumorigenesis in vivo during 35 days after OSCC cell injection. Our data showed that miR-140-5p expression was notably downregulated in OSCC tissues and cell lines. MiR-140-5p inhibited the expression of PAK4 by direct interaction in OSCC cells. Functional analysis disclosed that miR-140-5p overexpression or PAK4 knockdown suppressed cell proliferation, promoted cell apoptosis, and induced cell-cycle arrest in OSCC. Moreover, PAK4 upregulation rescued the detrimental effects of miR-140-5p on cell proliferation and cell-cycle progression and hampered cell apoptosis induced by miR-140-5p in OSCC. In vivo experiments demonstrated that miR-140-5p overexpression suppressed the growth of OSCC xenograft tumors by downregulating PAK4. In conclusion, our data revealed miR-140-5p suppressed OSCC tumorigenesis by targeting PAK4 in vitro and in vivo, deepening our understanding on the function and molecular basis of miR-140-5p in the development of OSCC.

Role of miR-182-5p overexpression in trichloroethylene-induced abnormal cell cycle functions in human HepG2 cells

Trichloroethylene (TCE), a widely used industrial solvent, occurs frequently in the global environment. TCE was found to induce hepatocarcinogenesis in mice and one of the underlying mechanisms was reported to involve miR-182-5p overexpression. Subsequently, miR-182-5p overexpression was shown to contribute to chemical-induced enhanced cell proliferation in mouse liver cells by targeting the gene Cited2. The aim of this study was to compare our findings in mice with those in a human hepatoma cell line HepG2. Data demonstrated that TCE at 0.1mM exerted no marked effect on human hepatoma cell line HepG2 cell migration, cell cycle, apoptosis, and DNA damage, but significantly stimulated cell proliferation rate and increased mRNA expression levels of proliferating cell nuclear antigen (PCNA), a cell proliferation biomarker. In addition, TCE enhanced miR-182-5p expression levels but lowered Cited2 mRNA expression. In summary, data showed that similar to mouse liver cells, TCE exposure also upregulated cells miR-182-5p expression and inhibited Cited2 expression in human hepatoma cell line HepG2. Our results suggest that the TCE-mediated alterations in the observed cellular functions involve interaction with miR-182-5p. It is of interest that utilization of liver cancer tissues from the Cancer Genome Atlas (TCGA) database also demonstrated that upregulated miR-182-5p expression and reduced Cited2 mRNA expression was detected suggesting that TCE-induced hepatocarcinogenesis involved processes similar to those in humans.

miR‑543 acts as a novel oncogene in oral squamous cell carcinoma by targeting CYP3A5

MicroRNAs (miRNAs/miRs) are small non-coding RNAs that can act as oncogenes or tumor-suppressor genes in human cancer. Previous studies have revealed that abnormal expression of miRNAs is closely associated with tumor cell cycle, differentiation, growth and apoptosis. miR-543 is expressed abnormally in a wide variety of cancers and has been associated with cellular proliferation, apoptosis, and invasion; however, the effect of miR-543 remains unknown in oral squamous cell carcinoma (OSCC). In the present study, the expression level of miR-543 in OSCC cell lines and tissues was investigated by RT-qPCR. A series of experiments was then performed to elucidate the functions of miR-543 in OSCC, such as CCK-8 assay, colony formation assay, flow cytometry, cell cycle distribution assay and cell apoptosis assay and Transwell assay. miR-543 expression was significantly upregulated in tumors from patients with OSCC and in OSCC cell lines. Overexpression of miR-543 promoted the proliferation, invasion and migration of OSCC cell lines, and inhibited cell apoptosis. In addition, the present study identified cytochrome P450 family 3 subfamily A member 5 (CYP3A5) as a direct target of miR-543 using software analysis and dual-luciferase reporter assays. In conclusion, the results of the present study suggest that miR-543 acts as a tumor promoter and serves a vital role in OSCC proliferation and invasion. These results confirm that miR-543 may serve as a potential novel target for the treatment of OSCC.

miR‑148a modulates the viability, migration and invasion of oral squamous cell carcinoma cells by regulating HLA‑G expression

Oral squamous cell carcinoma (OSCC) is a common malignancy of the oral and maxillofacial regions. MicroRNAs (miRs) are a group of endogenous small noncoding RNAs that inhibit gene expression by binding to the mRNA of target genes, and serve important roles in numerous biological processes. Reverse transcription-quantitative polymerase chain reaction and western blotting were used to detect gene and protein expression levels, respectively. Cell proliferation, migration and invasion were detected using MTT, wound healing and Matrigel assays, respectively. The association between miR-148a and human leukocyte antigen-G (HLA-G) was analyzed using Targetscan and Luciferase reporter assays. In the present study, miR-148a was revealed to be significantly downregulated in OSCC cells. To further investigate the functions of miR-148a in OSCC, the viability, migration, and invasive abilities of SCC-9 cells were investigated following transfection with miR-148a mimics or miR-148a inhibitor. It was revealed that transfection with miR-148a mimics significantly reduced the viability, migration and invasion of cells, whereas miR-148a inhibitor significantly enhanced these properties. In addition, HLA-G was identified as a direct target of miR-148a and demonstrated to be downregulated in OSCC cells. Furthermore, it was revealed that transfection with miR-148a mimics decreased the expression levels of HLA-G mRNA and protein in SCC-9 cells, whereas transfection with miR-148a inhibitor increased the expression of HLA-G mRNA and protein. The results indicated that there was an association between miR-148a and HLA-G expression, and suggested that miR-148a may be a potential target in the treatment of OSCC.

How hsa-miR-495 performed in the tumorigenesis of pancreatic adenocarcinoma by bioinformatics analysis

INTRODUCTION

Pancreatic adenocarcinoma (PAAD) is one of the most fatal cancers in the world for early metastasis, extensive invasion, and poor prognosis with a 5-year survival rate less than 5%. However, the underlying mechanisms are poorly understood. Therefore, it is urgent to explore molecular markers for early diagnosis or therapy target to improve the outcome of PAAD.

METHODS

We retrieved transcriptome data as well as clinical information from patients with PAAD in The Cancer Genome Altas (TCGA) database. Survival time associated microRNAs (miRNAs) and messenger RNAs (mRNAs) were initially identified, followed by enrichment analysis (Gene Ontology [GO] and pathway). The relationship between survival time associated miRNAs-mRNAs was also investigated to discover putative transcriptional control mechanisms of PAAD. Finally, by consulting the literature and retrieving the database, we found that hsa-miR-495 might have played an important role in PAAD.

RESULTS

In total, 146 miRNAs from 378 miRNAs and 580 mRNA from 17 100 mRNA, including 328 risk mRNA and 252 protective mRNA, were found to be associated with the survival time of PAAD. Eight hundred eighty-eight mRNA-miRNA pairs were related to the survival time of PAAD, involving in 755 mRNAs and 35 miRNAs. We chose 13 miRNAs predicted by target gene in the miRanda database for further research. Among these 13 miRNAs, hsa-miR-495 was identified as a good biomarker. Through GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, the significantly enriched pathways involved in focal adhesion, Staphylococcus aureus infection, and Intestinal immune network for immunoglobulin A production. And four target genes and 87 pathways of the hsa-miR-495 were enriched in PAAD. Interestingly, we found hsa-miR-495 with a low expression having a poor overall survival and significantly different recurrence rate within 5 years.

CONCLUSION

Hsa-miR-495 and its target genes may serve as a prognostic and predictive marker in PAAD. Further research on the function of the hsa-miR-495 and its target genes in the KEGG pathway may provide references for treatment of PAAD.

miR-93-5p may be an important oncogene in prostate cancer by bioinformatics analysis

INTRODUCTION

Prostate adenocarcinoma is one of the most prevalent causes of cancer-related deaths in males worldwide. However, the underlying mechanisms remain poorly understood. Hence, it is important to identify specific and effective therapeutic targets, to be able to determine appropriate therapy and management. So, this study aimed to predict that miR-93-5p is an important oncogene in prostate cancer by bioinformatics analysis.

METHODS

In this study, initially we identified differentially expressed genes (DEGs) and differently expressed miRNAs (DEMs) in the The Cancer Genome Atlas (TCGA) database, performed Gene Ontology (GO) and pathway enrichment analysis, then investigated the relationship between DEGs and DEMs, and finally through consulting the literature and retrieving the database, we found that miR-93-5p may play a major role in prostate cancer, so we predicted the expression and survival of miR-93-5p and its isomers by bioinformatics analysis, meanwhile, evaluated the function of miR-93-5p in vitro.

RESULTS

In total, 104 DEMs were differently expressed between prostate cancer and normal samples, including 56 downregulated ones and 48 upregulated ones; miR-93-5p (upregulated) was identified as a good biomarker. And 1904 DEGs were retrieved, including 794 downregulated ones and 1110 upregulated ones. We also obtained 1254 DEGs of the DEMs. In GO and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis, the significantly enriched pathways involved pathway in focal adhesion, vascular smooth muscle contraction, and regulation of actin cytoskeleton. By the KEGG pathway, we got 16 target genes and 92 pathways of the miR-93-5p in prostate cancer. We also found that the miR-93-5p and its isomers can express in prostate cancer, and which with a high expression had a poor overall survival and a significant difference recurrence rate within 5 years. Further in vitro verification results demonstrated that the low expression of miR-93-5p can inhibit cell proliferation, migration, invasion, change cell cycle, and promote early apoptosis of PC-3 cells.

CONCLUSION

The miR-93-5p and its target genes were used to define important molecular targets that could serve as a prognostic and predictive marker in the treatment of prostate cancer. Further research on the function of the miR-93-5p and its target genes in the KEGG pathway could provide references for the treatment of prostate cancer.

Incidence and mortality trends in oral and oropharyngeal cancers in China, 2005-2013

BACKGROUND

Oral and oropharyngeal cancers are among the most common cancers globally. This study aimed to assess the incidence and mortality trends of oral and oropharyngeal cancers in China between 2005 and 2013.

METHODS

Estimates of national trends of oral and oropharyngeal cancers were based on the data from Chinese Cancer Registry Annual Reports. The crude incidence rates of oral and oropharyngeal cancers between 2015 and 2035 were evaluated. The age-standardized rate was based on the world standard population.

RESULTS

It was estimated that 285,857 new cases and 132,698 deaths were related to oral and oropharyngeal cancers in China between 2005 and 2013, with mouth and tongue cancers being the most frequently diagnosed and the leading causes of death among all oral and oropharyngeal cancers. The incidence rates of oral and oropharyngeal cancer fluctuated from 1.69 to 1.89 per 100,000 person-years, and the mortality rate showed an increasing trend, ranging from 0.77 and 0.84 per 100,000 person-years. Males were more susceptible than females to oral and oropharyngeal cancers. The incidence and mortality rates of oral and oropharyngeal cancers were significantly higher in urban regions. The crude incidence rates of oral cancers are projected to increase from 2.26 to 3.21 per 100,000 person-years over the next 20 years in China.

CONCLUSION

The incidence of oral and oropharyngeal cancers fluctuated, whereas the mortality rate showed an upward trend from 2005 to 2013. A heavier burden from oral and oropharyngeal cancers is predicted in the next two decades in China.

MicroRNA-transcription factor network analysis reveals miRNAs cooperatively suppress RORA in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) represents over 90% of oral cancer incidence, while its mechanisms of tumorigenesis remain poorly characterized. In this study, we applied RNA-seq and microRNA-seq methodologies in four pairs of cancer and adjacent normal tissues to profile the contribution of miRNAs to tumorigenesis-altered functional pathways by constructing a comprehensive miRNA-mediated mRNA regulatory network. There were 213 differentially expressed (DE) miRNAs and 2172 DE mRNAs with the involvement of negative miRNA-mRNA interactions identified by at least two pairs of cancerous tissues. GO analysis revealed that the upregulated microRNAs significantly contributed to a global down-regulation of a number of transcription factors (TFs) in OSCC. Among the negative regulatory networks between the selected miRNAs (133) and TFs (167), circadian rhythm genes (RORA, RORB, RORC, and CLOCK) simultaneously regulated by multiple microRNAs were of particular interest. For instance, RORA transcript was predicted to be targeted by 25 co-upregulated miRNAs, of which, miR-503-5p, miR-450b-5p, miR-27a-3p, miR-181a-5p and miR-183-5p were further validated to directly target RORA, resulting in a stronger effect on RORA suppression together. In addition, we showed that the mRNA and protein expression levels of RORα were significantly decreased in most OSCC samples, associated with advanced clinical stage and poor prognosis. RORα significantly suppressed the proliferation of OSCC cells in vitro and in vivo. Attenuated RORα decreased p53 protein expression and suppressed p53 phosphorylation activity. Altogether, our results strongly suggest the importance of the role of miRNAs in regulating the activity of circadian rhythm-related TFs network during OSCC tumorigenesis, and provide further clues to understand the clinical link between circadian rhythm and cancer therapy.

Herpesviruses and MicroRNAs: New Pathogenesis Factors in Oral Infection and Disease?

The oral cavity incessantly encounters a plethora of microorganisms. Effective and efficient oral innate and adaptive immune responses are incumbent to maintain healthy mucosa. A higher prevalence of Human Herpesviruses (HHV), a family of large enveloped DNA viruses, has been reported in multiple oral inflammatory diseases suggesting their involvement in disease progression. However, the viral components contributing to oral disease remain obscure. MicroRNAs (miRNA) are non-protein coding, single stranded ribonucleic acid (RNA) molecules that post-transcriptionally regulate diverse messenger RNAs. Thus, miRNAs can control large repertoire of biological processes. Changes in miRNA expression are associated with various oral infections and diseases. Cellular miRNAs can act as pro- or anti-viral factors and dysregulation of host miRNA expression occurs during herpesviruses infection. This strongly suggest a critical role of cellular miRNAs in host-herpesvirus interaction. Interestingly, HHV also encode multiple miRNAs (called viral miRNAs) that may play key role in host-pathogen interaction by modulating both host biological pathways and controlling viral life cycle. Recent studies from our laboratory have identified viral miRNAs (v-miRs) in diseased oral tissue biopsies and demonstrate their immunomodulatory roles. This review discusses the association of miRNAs (both host and viral) and herpesviruses in the pathogenesis of oral inflammatory diseases.

MicroRNA-300 suppresses metastasis of oral squamous cell carcinoma by inhibiting epithelial-to-mesenchymal transition

Introduction

Oral cancer is the sixth most prevalent form of cancer, with oral squamous cell carcinomas (OSCCs) exhibiting the highest morbidity of all head and neck cancers. However, the specific metastatic mechanism is not yet clear. MicroR-300 (miR-300) has been identified as a critical regulator in tumor development. In this study, we focused on the roles of miR-300 in regulating epithelial–mesenchymal transition (EMT) in OSCC.

Methods

The surgical specimens from cases of OSCC (N=120) were collected, and the miR-300 expression was tested and the results were analyzed for possible correlations with clinical characteristics, and the prognostic significance was assessed by Kaplan–Meier analysis and Cox proportional hazards regression in OSCC patients. In addition, the proliferation and invasion of OSCC cells were evaluated after transfection of miR-300 mimics or inhibitor. At last, the role of miR-300 in EMT was investigated.

Results

The results showed that miR-300 levels were significantly lower in patients with OSCC than in controls and miR-300 levels in patients with OSCC were significantly associated with TNM classification. Kaplan–Meier analysis indicated that miR-300 with lower level had significantly decreased overall survival and disease-free survival of OSCC patients. In multivariate analysis, TNM stage, miR-300 expression and tobacco usage were the independent prognostic factors for overall survival and disease-free survival in OSCC. Moreover, in vitro experiments showed that miR-300 could inhibit the proliferation and invasion of OSCC cells. More importantly, miR-300 could inhibit the EMT process. In addition, we found that ET-1 could inhibit the expression of miR-300.

Conclusion

Our findings indicated that miR-300 could suppress metastasis of OSCC by inhibiting EMT. The present study indicates that miR-300 is a potential therapeutic agent for OSCC.

HPV epigenetic mechanisms related to Oropharyngeal and Cervix cancers

Human Papilloma Virus infection is very frequent in humans and is mainly transmitted sexually. The majority of infections are transient and asymptomatic, however, if the infection persists, it can occur with a variety of injuries to skin and mucous membranes, depending on the type of HPV involved. Some types of HPV are classified as high oncogenic risk as associated with the onset of cancer. The tumors most commonly associated with HPV are cervical and oropharyngeal cancer, epigenetic mechanisms related to HPV infection include methylation changes to host and viral DNA and chromatin modification in host species. This review is focused about epigenethic mechanism, such as MiRNAs expression, related to cervix and oral cancer. Specifically it discuss about molecular markers associated to a more aggressive phenotype. In this way we will analyze genes involved in meiotic sinaptonemal complex, transcriptional factors, of orthokeratins, sinaptogirin, they are all expressed in cancer in a way not more dependent on cell differentiation but HPV-dependent.

Targeting of miR-31/96/182 to the Numb gene during head and neck oncogenesis

BACKGROUND

MicroRNAs (miRNAs) play crucial roles in head and neck squamous cell carcinoma (HNSCC). This study investigates whether miR-31, miR-96, and miR-182 are involved in targeting Numb during HNSCC.

METHODS

The expression of miR-31/96/182 in tumor tissues was analyzed. Reporter assay, knockdown, expression, and oncogenic analysis were carried out in cell lines.

RESULTS

Upregulation of miR-31/96/182 was detected in tumor tissues. In addition, advanced tumors showed higher expression levels of these miRNAs. The expression of these miRNAs was upregulated after treatment with areca ingredients (P < .01 or P < .001). These miRNAs directly targeted the 3' untranslated region (UTR) sequence of the Numb gene. An increased migration and invasion of HNSCC cells was associated with the exogenous expression of miR-31/96/182 (P < .01 or P < .001), and this was reverted by expression of Numb.

CONCLUSION

This study provides new evidence demonstrating that there is frequent and concordant upregulation of miR-31, miR-96, and miR-182 during HNSCC and these miRNAs co-target Numb.

Expression and Regulation Profile of Mature MicroRNA in the Pig: Relevance to Xenotransplantation

The pig is an important source of meat production and provides a valuable model for certain human diseases. MicroRNA (miRNA), which is noncoding RNA and regulates gene expression at the posttranscriptional level, plays a critical role in various biological processes. Studies on identification and function of mature miRNAs in multiple pig tissues are increasing, yet the literature is limited. Therefore, we reviewed current research to determine the miRNAs expressed in specific pig tissues that are involved in carcass values (including muscle and adipocytes), reproduction (including pituitary, testis, and ovary), and development of some solid organs (e.g., brain, lung, kidney, and liver). We also discuss the possible regulating mechanisms of miRNA. Finally, as pig organs are suitable candidates for xenotransplantation, biomarkers of their miRNA in xenotransplantation were evaluated.

Molecular and serologic markers of HPV 16 infection are associated with local recurrence in patients with oral cavity squamous cell carcinoma

Human papillomavirus (HPV) infections predict mortality in Taiwanese patients with oral cavity squamous cell carcinoma (OCSCC). To address their prognostic significance for local recurrence (LR), in this retrospective cohort study we investigated different serologic and molecular markers of HPV 16 infection in 85 consecutive patients with primary OCSCC who received standard treatment and had their sera stored before treatment. Resected tumor specimens were examined with PCR-based assays for HPV 16 E6/E7 mRNA expression. Sera were tested with suspension arrays for the presence of HPV-specific antibodies using synthetic L1 and E6 peptides as well as a synthetic E7 protein. HPV 16 E6/E7 mRNA, anti-L1, anti-E6, and anti-E7 antibodies tested positive in 12%, 25%, 38%, and 41% of the study patients, respectively. Multivariate analysis identified pathological T3/T4, E6/E7 mRNA, and anti-E7 antibodies as independent risk factors for LR, whereas anti-E6 antibodies were an independent protective factor. In patients with ≥ 3 (high-risk group), 2 (intermediate-risk), and ≤ 1 (low-risk) independent risk factors (predictors), the 5-year LR rates were 75%, 42%, and 4%, respectively. Results were validated in an independent cohort. Together, our preliminary data indicate that HPV 16 infections as well as low and high serum levels of anti-E6 and anti-E7 antibodies, respectively, can serve as biomarkers of LR in patients with OCSCC, whereas the clinical usefulness of anti-HPV 16 antibodies for risk stratification of newly diagnosed cases deserves further scrutiny.

MicroRNAs as effective surrogate biomarkers for early diagnosis of oral cancer

BACKGROUND

Oral squamous cell carcinomas (OC) are life-threatening diseases emerging as major international health concerns.

OBJECTIVE

Development of an efficient clinical strategy for early diagnosis of the disease is a key for reducing the death rate. Biomarkers are proven to be an effective approach for clinical diagnosis of cancer. Although mechanisms underlying regulation of oral malignancy are still unclear, microRNAs (miRNAs) as a group of small non-coded RNAs may be developed as the effective biomarkers used for early detection of oral cancer.

METHODS

A literature search was conducted using the databases of PubMed, Web of Science, and the Cochrane Library. The following search terms were used: miRNAs and oral cancer or oral carcinoma. A critical appraisal of the included studies was performed with upregulated miRNAs and downregulated miRNAs in oral cancer.

RESULTS

In this review, we summarize the research progress made in miRNAs for diagnosis of oral cancer. The involvement of miRNAs identified in signal transduction pathways in OC, including Ras/MAPK signaling, PI3K/AKT signaling, JAK/STAT signaling, Wnt/β-catenin signaling, Notch signaling, and TGF-β/SMAD signaling pathway.

CONCLUSIONS

A number of studies demonstrated that miRNAs may be developed as an ideal set of biomarkers used for early diagnosis and prognosis of cancers because of the stability in human peripheral blood and body fluids and availability of non-invasive approaches being developed for clinical utility.

CLINICAL RELEVANCE

These findings suggest that miRNAs as biomarkers may be useful for diagnosis of OC.

MiR-370 promotes apoptosis in colon cancer by directly targeting MDM4

MicroRNA (miR)-370 functions as a tumor suppressor or promoter in several cancers. However, the expression and biological role of miR-370 in colon cancer remains undefined. In the present study, miR-370 expression in both normal and malignant colon tissues was quantified by quantitative polymerase chain reaction. An in vitro cell viability and apoptosis assay and an in vitro xenograft tumor model were employed to investigate the role of miR-370 on colon cancer growth. Furthermore, the potential direct target of miR-370 was identified using a luciferase assay. Our results demonstrate that down-regulation of miR-370 expression occurs in malignant tissues and miR-370 expression is inversely correlated with tumor grade. Moreover, we determined that miR-370 functions as a tumor suppressor in colon cancer by inhibiting cell proliferation and promoting cell apoptosis. In addition, overexpression of miR-370 impairs xenograft tumor growth in nude mice. Mechanistically, mouse double minute 4 (MDM4) was demonstrated to be a potential direct target of miR-370, inducing apoptosis in colon cancer. Collectively, these findings suggest that upregulation of miR-370 may impair colon tumor growth by directly targeting MDM4. These findings provide a new direction for the diagnosis and treatment of colon cancer.

Knockdown of SOX2OT inhibits the malignant biological behaviors of glioblastoma stem cells via up-regulating the expression of miR-194-5p and miR-122

Background

Accumulating evidence has highlighted the potential role of long non-coding RNAs (lncRNAs) in the biological behaviors of glioblastoma stem cells (GSCs). Here, we elucidated the function and possible molecular mechanisms of the effect of lncRNA-SOX2OT on the biological behaviors of GSCs.

Results

Real-time PCR demonstrated that SOX2OT expression was up-regulated in glioma tissues and GSCs. Knockdown of SOX2OT inhibited the proliferation, migration and invasion of GSCs, and promoted GSCs apoptosis. MiR-194-5p and miR-122 were down-regulated in human glioma tissues and GSCs, and miR-194-5p and miR-122 respectively exerted tumor-suppressive functions by inhibiting the proliferation, migration and invasion of GSCs, while promoting GSCs apoptosis. Knockdown of SOX2OT significantly increased the expression of miR-194-5p and miR-122 in GSCs. Dual-luciferase reporter assay revealed that SOX2OT bound to both miR-194-5p and miR-122. SOX3 and TDGF-1 were up-regulated in human glioma tissues and GSCs. Knockdown of SOX3 inhibited the proliferation, migration and invasion of GSCs, promoted GSCs apoptosis, and decreased TDGF-1 mRNA and protein expression through direct binding to the TDGF-1 promoter. Over-expression of miR-194-5p and miR-122 decreased the mRNA and protein expression of SOX3 by targeting its 3’UTR. Knockdown of TDGF-1 inhibited the proliferation, migration and invasion of GSCs, promoted GSCs apoptosis, and inhibited the JAK/STAT signaling pathway. Furthermore, SOX3 knockdown also inhibited the SOX2OT expression through direct binding to the SOX2OT promoter and formed a positive feedback loop.

Conclusion

This study is the first to demonstrate that the SOX2OT-miR-194-5p/miR-122-SOX3-TDGF-1 pathway forms a positive feedback loop and regulates the biological behaviors of GSCs, and these findings might provide a novel strategy for glioma treatment.

Electronic supplementary material

The online version of this article (10.1186/s12943-017-0737-1) contains supplementary material, which is available to authorized users.

miR-195-5p Suppresses the Proliferation, Migration, and Invasion of Oral Squamous Cell Carcinoma by Targeting TRIM14

MicroRNAs (miRNAs) play an essential role in tumor biological processes through interacting with specific gene targets. The involvement of miR-195-5p in cell proliferation, invasion, and migration has been demonstrated in several cancer cell lines, while its function in oral squamous cell carcinoma (OSCC) remains unclear. Here we find that miR-195-5p expression is lower in OSCC than in nontumor tissues, while its overexpression in cell lines can lead to the promotion of apoptosis and the reduction of cell growth, migration, and invasion. Moreover, we identify the tripartite motif-containing protein (TRIM14) as a target of miR-195-5p. Therefore, we reason that the tumor suppressor role of miR-195-5p in OSCC is dependent on the interaction with TRIM14.

Identification and bioinformatics analysis of miRNAs associated with human muscle invasive bladder cancer

Accumulated evidence has indicated that micro (mi)RNAs play vital roles in the occurrence and development of human muscle invasive bladder cancer (MIBC), however, little is known about the miRNAs' regulatory networks. In the present study, the authors aimed to use bioinformatics analysis to identify the key miRNAs and potential target genes, as well as studying the underlying mechanisms for MIBC. They collected several human MIBC tissues to generate a miRNA expression analysis by microarray analysis comparing with normal bladder tissues, identifying 104 differentially expressed miRNAs (102 were downregulated and 2 were upregulated) and predicted 11,884 putative target genes of the dysregulated miRNAs. To understand the function of dysregulated miRNAs in the development of MIBC, networks among miRNAs and genes, gene ontologies and pathways were built. The subsequent bioinformatics analysis indicated that the mitogen-associated protein kinase (MAPK) signaling pathway, apoptosis and pathways in cancer and the cell cycle, were significantly enriched Overall, these results provided comprehensive information on the biological function of dysregulated miRNAs in the development of MIBC. The identification of miRNAs and their putative targets may offer new diagnostic and therapeutic strategies for human muscle invasive bladder cancer.

Dysregulation of an X-linked primate-specific epididymal microRNA cluster in unexplained asthenozoospermia

Asthenoszoopermia, characterized by reduced sperm motility, is one of the primary forms of male infertility. Whereas most cases were diagnosed into unexplained asthenozoospermia (UA) because the etiology cannot be identified. In animal models, epigenetic dysregulation in epididymis can impair sperm maturation and result in asthenozoospermia. However, researches of epididymal epigenetic regulation on humans are impeded by the difficulty in obtaining epididymal tissues. We previously identified cell-free seminal microRNAs predominately derived from epididymis in human ejaculate. In the present study, these microRNAs were used to screen and validate the microRNA dysregulation in men with UA, which were divided into screening set and validation set. The expression of five miRNAs (miR-891b, miR-892b, miR-892a, miR-888 and miR-890) was found and confirmed to be dysregulated in men with UA. Interestingly, these five miRNAs belong to a primate-specific miRNA cluster located on the X chromosome with epididymis specific expression. Moreover, obvious coherent dysregulation of these miRNAs were observed in 13% men with UA. Regression analysis demonstrated that levels of these miRNAs were significantly correlated with progressive sperm motility. Functions and pathways of predicted target genes of this cluster suggested its role in sperm maturation. Dysregulation of this miRNA cluster might be an epigenetic basis for some patients with UA. We also showed a noninvasive and feasible approach to get epigenetic information of human epididymis.

MiR-451 as a new tumor marker for gastric cancer

Gastric cancer is the second most common malignancy in China. However, the prognosis for gastric cancer patients remains poor. The purpose of this study was to investigate whether miR-451 was a potential prognostic biomarker for gastric cancer. Fresh tissues were immediately frozen in liquid nitrogen until use. The plasma was extracted and quantitative real-time polymerase chain reaction was performed to detect miR-451 expression. The Student's t test analysis and multivariate Cox regression analysis were performed to analyze expression of miR-451. The analysis results showed that the expression level of miR-451 was decreased expression in gastric cancer tissue. The down-regulation of miR-451 tended to be positively correlated with tumor stage, lymphatic metastasis and shorter overall survival of patients. MiR-451 may be a potential biomarker and a potential therapeutic target for the diagnoses and prognosis of gastric cancer.

Clinical value of miR-145-5p in NSCLC and potential molecular mechanism exploration: A retrospective study based on GEO, qRT-PCR, and TCGA data

MicroRNAs have been reported to be involved in various biological processes. Here, we performed a systematic analysis to explore the clinical value and potential molecular mechanism of miR-145-5p in non-small cell lung cancer. First, a meta-analysis was performed with eligible literature, followed by microRNA microarrays in the Gene Expression Omnibus database, to verify the diagnostic and prognostic values of miR-145-5p. A cohort of 125 clinical paired non-small cell lung cancer samples was next used to detect the level of miR-145-5p and to explore the relationship of miR-145-5p with clinicopathological parameters. The Cancer Genome Atlas database was additionally applied to investigate the role of miR-145-5p in non-small cell lung cancer. The potential targets of miR-145-5p were predicted using 12 online prediction databases to explore the prospective molecular mechanism of miR-145-5p in non-small cell lung cancer. The expression of miR-145-5p in non-small cell lung cancer was significantly lower than that in healthy tissues. And miR-145-5p tended to show better diagnostic performance in lung squamous cell carcinoma than in lung adenocarcinoma. Furthermore, the expression of miR-145-5p was closely associated with lymph node metastasis in non-small cell lung cancer. Gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis revealed that the target genes were mainly enriched with enzyme-linked receptor protein signaling pathways, SH3 domain binding, cell leading edge, and adherens junction. The protein-protein interaction network showed that eight hub genes (SMAD4, SMAD2, IRS1, FOXO1, ERBB4, NRAS, ACTB, and ACTG1) might be the key target genes of miR-145-5p in non-small cell lung cancer. The information we obtained might offer new perspectives for clinical diagnosis and treatment for non-small cell lung cancer.

MicroR-545 mediates colorectal cancer cells proliferation through up-regulating epidermal growth factor receptor expression in HOTAIR long non-coding RNA dependent

The functional impact of recently discovered miRNAs in human cancer remains to be clarified. One miRNA in colorectal cancer which has attracted attention is miR-545. In this study, we examined the function of miR-545 in proliferation of colorectal cancer cells. Expressions of HOTAIR, miRNA-545, and epidermal growth factor receptor (EGFR) mRNA were measured in 100 paired cancerous and non-cancerous tissues as well as in SW480 and LOVO colorectal cancer cell (CRC) lines by quantitative RT-PCR. The relative protein level of EGFR was measured using western blotting. Effects of miRNA-545 and HOTAIR on gastric cancer cells were studied by overexpression and RNA interference approaches. Insight of mechanism of promotion cancer by miR-545 was gained from luciferase reporter assay and gene expression analysis. CRC proliferation was evaluated using clone formation and MTT assay. Differential expressions of HOTAIR, miR-545, and EGFR were observed in cancerous tissues in comparison to non-cancerous tissues. By expressional management of miR-545, we observed that miR-545 negatively regulated cell proliferation. Also luciferase reporter assay revealed that miR-545 inhibited regulated EGFR expression by affecting its 3'-UTR activity. In addition, miR-545 expression was suppressed by HOTAIR overexpression whereas enhanced by HOTAIR silence. Suppression of EGFR expression by miR-545 mimic was abrogated by HOTAIR overexpression. Monitoring of tumor growth in mice showed that miR-545 overexpression suppressed LOVO tumor growth. Our data suggested that HOTAIR long non-coding RNA mediates microR-545 regulating colorectal cancer cells proliferation.

A functional variant at the miRNA binding site in E2F1 gene is associated with risk and tumor HPV16 status of oropharynx squamous cell carcinoma

Human papillomavirus (HPV) activates E2F1-driven transcription via the E7-RB1-E2F pathway. Genetic polymorphisms in the 3' untranslated region (UTR) targeted by miRNAs can affect the regulation of target genes and individual cancer risk. Thus, we hypothesized that a polymorphism at the 3'UTR miRNA binding site of E2F1 gene (rs3213180) was associated with risk of oral squamous cell carcinoma (OSCC) and tumor HPV status of oropharynx squamous cell carcinoma (OPSCC). We determined the E2F1rs3213180 polymorphism and HPV16 L1 serology of 325 OSCC patients and 335 controls, and tumor HPV16 status of 552 OPSCC. Logistic regression models were used to calculate associations of E2F1rs3213180 polymorphism with risk of HPV-associated OSCC and tumor HPV status of OPSCC. The risk of HPV-associated OSCC was modified by the E2F1rs3213180 polymorphism. Patients with both HPV seropositivity and the Ins/Del or Ins/Ins genotype of E2F1rs3213180 had the highest risk of OSCC, while the lowest risk was detected in patients with HPV seronegativity and the Del/Del genotype. A similar and more prominent effect was detected in OPSCC, but not in oral cavity squamous cell carcinoma (OCSCC) patients. Notably, that effect trend was pronounced in never-smokers and never-drinkers. Furthermore, the patients with the E2F1rs3213180 Ins/Del or Ins/Ins genotype were 2.9 times more likely to have HPV-positive tumors than those with the Del/Del genotype. Our results suggest that the E2F1rs3213180 polymorphism may influence susceptibility to HPV-associated OSCC, particularly for OPSCC, never-smokers and never-drinkers, but not for patients with OCSCC. Additional larger population and functional studies are warranted to confirm our findings. © 2016 Wiley Periodicals, Inc.

MiR-367 negatively regulates apoptosis induced by adriamycin in osteosarcoma cells by targeting KLF4

Diverse functions of microRNAs have been investigated in tumorigenesis in osteosarcoma (OS), involving the regulation of proliferation, invasion, migration, apoptosis and drug resistance. MiR-367 was found to be an oncogene and increased in OS. However, the function of miR-367 in drug resistance in OS cells is still unknown. In this study, we found that miR-367 was up-regulated in OS tissues and OS cell cultures. Meanwhile, treatment with adriamycin (ADR) induced apoptosis of OS cells with upregulation of miR-367. Notably, KLF4 was demonstrated to be a direct target of miR-367 by gene reporter assay, and miR-367 significantly blocked both mRNA and protein level of KLF4. In addition, overexpression of miR-367 markedly suppressed the increase of KLF4 induced by ADR in OS cells, as well as Bax and cleaved caspase-3, which were significantly reversed by anti-miR-367 transfection. Taken together, our data demonstrates that miR-367 and KLF4 play important roles in OS treatment and ADR resistance, suggesting that miR-367 is a potential biomarker of chemotherapy resistance in OS and also probably a novel therapeutic target against OS.

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miR-367 functions as an oncogene in OS targeting the tumor suppressor KLF4.

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ADR induces apoptosis in OS via miR-367/KLF4/Bax signaling pathway.

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miR-367 enhances the resistance of ADR to OS cells through suppressing KLF4.

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miR-367 could be a potential biomarker of chemotherapy resistance against OS.

Gastric cardia adenocarcinoma microRNA profiling in Chinese patients

Gastric cardia adenocarcinoma (GCA), which occurs at the gastroesophageal boundary, is one of the most malignant types of cancer. Over the past 30 years, the incidence of GCA has increased by approximately sevenfold, which has a more substantial increase than that of many other malignancies. However, as previous studies mainly focus on non-cardia gastric cancer, until now, the mechanisms behind GCA remain largely unknown. MicroRNAs (miRNAs) have been shown to play pivotal roles in carcinogenesis. To gain insight into the molecular mechanisms regulated by miRNAs in GCA development, we investigated miRNA expression profiles using 81 pairs of primary GCAs and corresponding non-tumorigenic tissues. First, 21 pairs of samples were used for microarray analysis, and then another 60 pairs of samples were used for further analysis. Our results showed that 464 miRNAs (237 upregulated, 227 downregulated, false discovery rate FDR <0.05) were differently expressed between GCA and non-tumor tissues. Pearson test and pathway analysis revealed that these dysregulated miRNA correlated coding RNAs may have effects on several cancer-related pathways. Four miRNAs (miR-1244, miR-135b-5p, miR-3196, and miR-628-3p) were found to be associated with GCA differentiation. One miRNA, miR-196a-5p, was found to be associated with age of GCA onset. Further, survival analysis showed that the expression level of miR-135b-5p was associated with GCA survival. Taken together, our study first provided the genome-wide expression profiles of miRNA in GCA and will be good help for further functional studies.

Lipoplexes from Non-viral Cationic Vectors: DOTAP-DOPE Liposomes and Gemini Micelles

This chapter describes the topic of gene therapy based on colloidal drug delivery, as an alternative to the use of viral carriers. Non-viral vectors are promising transfection agents and do not suffer from limitations related to toxicity and immunogenic effects. In particular, lipid-based aggregates are generally considered biocompatible and versatile nanocarriers whose composition can be designed to include a cationic molecule which ensures strong interaction with nucleic acid. Herein the main issues related to complex formation and in vitro administration are illustrated with key examples, such as liposome-DNA plasmid (pDNA) association and micelles-siRNA complexes.

Caspase-8 polymorphisms and risk of oral squamous cell carcinoma

Caspase-8 (CASP8) is a key controller of apoptosis, and its deregulation is crucially involved in carcinogenesis. The aim of the present study was to evaluate the function of CASP8 polymorphisms in oral squamous carcinoma (OSCC) by evaluating the risk associated with three single-nucleotide polymorphisms (SNPs) in a case-control study in a Han Chinese patient population. A total of 505 individuals with clinically diagnosed OSCC and 507 healthy controls were tested for the three SNPs rs3834129, rs13016963 and rs1045485, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing analysis. After adjusting for other confounders, the genotype frequencies of CASP8 -652 6N ins/del promoter polymorphism (rs3834129) were found to be lower in patients with OSCC compared with normal subjects. No significant difference was detected in the genotype frequencies of rs13016963 between the patients and control subjects. However, the AA genotype frequency of rs1306963 was associated with OSCC as a risk factor among non-smokers and non-drinkers. For CASP8, rs1045485 was not present in any of the patients with OSCC or control subjects. These results suggest that the del allele of rs3834129 may play a protective role in the tumorigenesis of OSCC and may be useful as a genetic susceptibility marker for OSCC in the population studied.