miRNAs In Cervical Cancer Research Articles

HPV16-miRNAs exert oncogenic effects through enhancers in human cervical cancer

BackgroundCervical cancer is a human papillomavirus (HPV)-related disease. HPV type 16 (HPV16), which is the predominant cause of cervical cancer, can encode miRNAs (HPV16-miRNAs). However, the role of HPV16-miRNAs in the pathogenesis of cervical cancer remains unclear.MethodsHuman cervical cancer cell lines SiHa (HPV16-positive) and C33A (HPV-negative), and cervical cancer tissues were collected to investigate the expression levels of two HPV16-miRNAs (HPV16-miR-H1 and HPV16-miR-H6). The overexpression and knockdown of HPV16-miR-H1 and HPV16-miR-H6 were performed using the lentiviral vector system and miRNA inhibitors, respectively. RNA-sequencing (RNA-seq) analysis and H3K27ac chromatin immunoprecipitation and sequencing (CHIP-seq) experiments were utilized to explore the roles of HPV16-miR-H1 and HPV16-miR-H6 facilitated by enhancers. CCK8, EdU, transwell, and wound healing assays were performed to verify the effects of HPV16-miR-H1 and HPV16-miR-H6 on cell proliferation and migration.ResultsHPV16-miR-H1 and HPV16-miR-H6 were highly expressed in both SiHa cells and tissue samples from HPV16-positive cervical cancer patients. RNA-seq analysis showed that HPV16-miR-H1 and HPV16-miR-H6 induced the upregulation of numerous tumor progression-associated genes. H3K27ac CHIP-seq experiments further revealed that HPV16-miR-H1 and HPV16-miR-H6 modulated the expression of critical genes by regulating their enhancer activity. The functional study demonstrated that HPV16-miR-H1 and HPV16-miR-H6 increased the migratory capacity of SiHa cells.ConclusionsOur data shed light on the role of HPV16-encoded miRNAs in cervical cancer, particularly emphasizing their involvement in the miRNA-enhancer-target gene system. This novel regulatory mechanism of HPV16-miRNAs provides new insights and approaches for the development of therapeutic strategies by targeting HPV16-positive cervical cancer.

Hsa-miR-194-5p and hsa-miR-195-5p are down-regulated expressed in high dysplasia HPV-positive Pap smear samples compared to normal cytology HPV-positive Pap smear samples

BackgroundThe human papillomavirus (HPV) infection may affect the miRNA expression pattern during cervical cancer (CC) development. To demonstrate the association between high-risk HPVs and the development of cervix dysplasia, we examined the expression patterns of hsa-miR-194-5p and hsa-miR-195-5p in Pap smear samples from southeast Iranian women. We compared samples that were HPV-positive but showed no abnormality in the cytological examination to samples that were HPV-positive and had severe dysplasia.MethodsPap smear samples were obtained from 60 HPV-positive (HPV-16/18) patients with histologically confirmed severe dysplasia (cervical intra-epithelial neoplasia (CIN 3) or carcinoma in situ) and the normal cytology group. The expression of hsa-miR-194-5p and hsa-miR-195-5p was analyzed by real-time quantitative PCR, using specific stem-loop primers and U6 snRNA as the internal reference gene. Clinicopathological features were associated with miRNA expression levels. Furthermore, functional enrichment analysis was conducted using in silico tools. The Kaplan–Meier survival method was also obtained to discriminate survival-significant candidate miRNAs in CC, and receiver operating characteristic (ROC) curves were constructed to assess the diagnostic value.ResultsCompared to HPV-positive cytologically normal Pap smear samples, hsa-miR-194-5p and hsa-miR-195-5p relative expression decreased significantly in HPV-positive patients with a severe dysplasia Pap smear. Kaplan–Meier analysis indicated a significant association between the miR-194 decrease and poor CC survival. In essence, ROC curve analysis showed that miR-194-5p and miR-195-5p could serve as valuable markers for the development of cervix dysplasia in individuals who are positive for high-risk HPVs.ConclusionsThis study revealed that hsa-miR-194-5p and hsa-miR-195-5p may possess tumor suppressor capabilities in the context of cervical dysplasia progression. However, it remains uncertain whether these microRNAs are implicated in the transition of patients with high dysplasia to cervical cancer. We also showed the potential capability of candidate miRNAs as novel diagnostic biomarkers related to cervical dysplasia progression.

Evaluation of Exosomal miRNA as Potential Biomarkers in Cervical Cancer.

Different studies show that small non-coding RNAs, such as microRNAs (miRNAs) obtained from exosomes, are considered potential biomarkers in several types of cancer, including cervical cancer (CC). Therefore, the present study seeks to present an overview of the role of circulating exosomal miRNAs with the potential to act as biomarkers for the diagnosis and prognosis of CC and to analyze the presence of these miRNAs according to the stage of CC. For this purpose, a review was developed, with articles consulted from the electronic databases MEDLINE/PubMed, Scopus, and Web of Science published between 2015 and 2021. Seven articles were included after a selection of studies according to the eligibility criteria. In addition to the methods used for sample analysis, detection, and isolation of miRNAs in each article, clinical data were also extracted from the patients studied, such as the stage of cancer. After analyzing the network of the seven miRNAs, they were associated with the immune system, CC progression and staging, and cisplatin resistance. With the belief that studies on miRNAs in cervical cancer would have major clinical implications, in this review, we have attempted to summarize the current situation and potential development prospects.

Quercetin up-regulates the expression of tumor-suppressive microRNAs in human cervical cancer.

Quercetin, a flavonol present in many vegetables and fruits, has been identified as a chemoprevention agent in several cancer models. However, the molecular mechanism of quercetin's anticancer activity is not entirely understood. MicroRNAs (miRNAs), small noncoding RNAs, have been reported to play key roles in various biological processes by regulating their target genes. We hypothesized that quercetin can exert an anticancer effect through the regulation of miRNAs. To test this hypothesis, we investigated the effects of quercetin on the expression of tumor-suppressive miRNAs in cervical cancer. Quercetin up-regulated the in vivo and in vitro expression of tumor-suppressive miRNAs miR-26b, miR-126, and miR-320a. Quercetin suppressed the level of β-catenin, encoded by catenin beta 1 (CTNNB1), by up-regulating miR-320a in HeLa cells. Moreover, quercetin increased the expression of mir-26b, mir-126, and mir-320a precursors in HeLa cells. The results from this study show that quercetin has the potential to prevent cervical cancer by regulating the expression of tumor-suppressive miRNAs.

A Clinical Investigation on the Theragnostic Effect of MicroRNA Biomarkers for Survival Outcome in Cervical Cancer: A PRISMA-P Compliant Protocol for Systematic Review and Comprehensive Meta-Analysis.

Background: The most often diagnosed malignancy in women worldwide is cancer of the cervix. It is also the most prevalent kind of gynecological cancer in women. This cancer originates in the opening of the cervix and spreads through sexual contact. Even though human papillomavirus (HPV) may not cause cancer immediately, it does develop over time as a result of the virus’s lengthy persistence to cause dysplastic changes overtime, particularly in high-risk kinds. The primary objective of this research is to see if miRNAs are dysregulated as a result of treatment resistance in cervical cancer (CC). The aim is to see if these microRNAs may be utilized as biomarkers for detecting chemoresistance in CC, particularly for clinical applications. Methods: The recommended protocol for comprehensive study and meta-analysis (PRISMA-P) standards will be utilized for the analysis and data interpretation. The bibliographic databases will be methodically searched using a combination of search keywords. Based on established inclusion and exclusion criteria, the acquired findings will be reviewed, and data retrieved from the selected scientific papers for systematic review. We will then construct a forest from the pooled Hazard ratio (HR) and 95% C.I. values, data obtained using the random-effects model. Discussion: The focus of this study is to identify the function of miRNAs as a chemoresistance regulator and determine if they have the potential scope to be considered as biomarkers for cervical cancer. Through this systematic review and meta-analysis, the goal is to collect, compare, and analyze the data pertaining to the role of miRNAs in cervical cancer, thereby, enabling us to understand the role they play in chemosensitivity.

MiR-552 promotes the proliferation and metastasis of cervical cancer cells through targeting MUC15 pathway.

Accumulating evidence shows that microRNAs (miRNAs) play key roles in tumorigenesis, progression, recurrence and drug resistance of malignant tumors. The tumor-promoting role of miR-552 has been evidenced in multiple tumors. Yet, the relevance of miR-552 in cervical cancer remains undetermined. This study aimed to investigate the role of miR-552 in cervical cancer proliferation and metastasis. Herein, we for first found that miR-552 expression was upregulated in cervical cancer tissues compared with their normal controls. Functional assays revealed that miR-552 promoted the proliferation and metastasis of cervical cancer cells. Mechanically, bioinformatics and luciferase reporter analysis identified MUC15 as a direct target of miR-552. Reduced MUC15 expression was detected in cervical cancer, and MUC15 overexpression exhibited a tumor-suppressive effect. MUC15 restoration partially abolished the discrepancy of growth and metastasis capacity between miR-552 overexpression cervical cancer cells and control cells. Taken together, these data demonstrate that miR-552 acts as a potential oncogene miRNA in cervical cancer, which exerts its function through targeting MUC15.

MicroRNA‑15a‑5p‑targeting oncogene YAP1 inhibits cell viability and induces cell apoptosis in cervical cancer cells.

MicroRNAs (miRNAs) have been reported to have important regulatory roles in the progression of several types of cancer, including cervical cancer (CC). However, the biological roles and regulatory mechanisms of miRNAs in CC remain to be fully elucidated. The aim of the present study was to examine the functions of miRNAs in CC and the possible mechanisms. Using a microarray, it was identified that miRNA-15a-5p (miR-15a-5p) was one of the most down-regulated miRNAs in CC tissues compared with adjacent noncancerous tissues. The low expression of miR-15a-5p was observed in CC tumor tissues with distant metastasis and in CC cell lines. In addition, the effects of miR-15a-5p upregulation on cell viability, apoptosis, invasion and migration of CC cells were investigated using CCK-8, flow cytometry, Transwell and wound healing assays, respectively. It was demonstrated that upregulation of miR-15a-5p significantly suppressed the viability, migration and invasion, and promoted the apoptosis of SiHa and C-33A cells. Furthermore, yes-associated protein 1 (YAP1), a well-known oncogene, was confirmed to be directly targeted by miR-15a-5p and was found to be negatively regulated by miR-15a-5p. Further correlation analysis indicated that miR-15a-5p expression was negatively correlated with YAP1 expression in CC tissues. Notably, overexpression of YAP1 abrogated the tumor suppressive effects of miR-15a-5p in CC cells. Taken together, these present findings indicated that the miR-15a-5p/YAP1 axis may provide a novel strategy for the clinical treatment of CC.

Study on the antitumor activity and mechanism of novel targeted nanodrugs based on miRNA in cervical cancer

The aim of this study was to investigate the effect of different concentrations of novel targeted nanodrugs based on miRNA on the antitumor activity and mechanism in cervical carcinoma A549 cells. The MTT method was used to determine the effect of different concentrations of novel targeted nanodrugs based on miRNA on A549 cell proliferation, and annexin V FITC/PI double staining flow cytometry was performed to analyze the effect of these nanodrugs on A549 cell apoptosis. Western blotting was performed to observe the effect of these nanodrugs on the expression of Bax, Bcl-2, and caspase-3-related genes involved in A549 cell apoptosis. Compared with the control group, the novel targeted nanodrugs based on miRNA significantly inhibited the proliferation of A549 cells in a time- and dose-dependent manner. Results of double staining flow cytometry demonstrated that these nanodrugs could increase the apoptotic rate of A549 cells in a dose-dependent manner 48 h later. Western blotting revealed that these nanodrugs could upregulate the expression of Bax and caspase3 genes and downregulate the expression of Bcl-2 gene. Nanodrugs display an obvious antitumor activity in vitro, and the underlying mechanism may be associated with the upregulation of Bax and caspase-3 gene expression and the downregulation of Bcl-2 gene expression.

MiR-216a-3p suppresses the proliferation and invasion of cervical cancer through downregulation of ACTL6A-mediated YAP signaling.

The tumor-suppressive role of microRNA-216a-3p (miR-216a-3p) has been evidenced in multiple tumors. Yet, the relevance of miR-216a-3p in cervical cancer remains undermined. The current study was designed to determine the expression and potential function of miR-216a-3p in cervical cancer. Expression of miR-216a-3p was markedly decreased in cervical cancer and functional assays revealed an inhibitory effect of miR-216a-3p on the proliferation, colony formation, and invasion of cervical cancer. Actin-like 6A (ACTL6A) was identified as a target gene of miR-216a-3p. Elevated ACTL6A expression was detected in cervical cancer, and ACTL6A inhibition exhibited a tumor-suppressive effect. ACTL6A inhibition increased yes-associated protein (YAP) phosphorylation and downregulated YAP-mediated transcriptional activity. ACTL6A restoration or YAP reactivation partially abrogated the miR-216a-3p-mediated antitumor effect in cervical cancer cells. Taken together, these data demonstrate that miR-216a-3p acts as a potential tumor-suppressive miRNA in cervical cancer, which exerts its function through inhibition of YAP signaling via targeting ACTL6A.

HPV16+ -miRNAs in cervical cancer and the anti-tumor role played by miR-5701.

The early diagnosis of cervical cancer is difficult, resulting in an unsatisfactory prognosis. The present study aimed to explore the expression of HPV16-related microRNAs (miRNAs) in the serum of Uygur cervical cancer in Sinkiang and analyze the miRNAs showing different expression. The serum of 30 HPV16 positive (HPV16Pos) and 30 negative patients (HPV16Neg) was collected and then the differentially expressed miRNAs were screened out by function and pathway enrichment analyses. Next, the cervical cancer cells were cultured. miR-5701-mimic and inhibitor were transfected into cells. The level of miR-5701 was detected by a quantitative reverse transcriptase-polymerase chain reaction. The proliferation of cells was detected using a Cell Counting Kit-8 assay. Western blotting was used to measure the expression of THBS4. We identified three up-regulated miRNAs (hsa-miR-1291, hsa-miR-144-5p and hsa-miR-5701) and seven down-regulated known-miRNAs (hsa-miR-21-5p, hsa-miR-101-3p, hsa-miR-370-3p, hsa-miR-151a-3p, hsa-miR-144-3p, hsa-miR-199a-3p and hsa-miR-199b-3p) relative to HPV16Neg. The mitogen-activated protein kinase signal pathway is predicted to be a key mechanism of HPV16-related cervical cancer. Furthermore, miR-5701 inhibits the proliferation of cervical cancer cells and suppresses the expression of THBS4 (P < 0.05), which was confirmed as a target gene of miR-5701. In the present study, we confirm 10 differentially expressed miRNAs that could be potential markers or therapeutic targets of cervical cancer. miR-5701 inhibits the proliferation of cervical cancer cells and the expression of its target gene THBS4.

MicroRNA-889-3p targets FGFR2 to inhibit cervical cancer cell viability and invasion.

MicroRNAs (miRNAs) are frequently dysregulated in cervical cancer, and the aberrant regulation of miRNAs may be involved in the regulation of various cancer-associated biological processes. Therefore, further exploration of the specific roles of dysregulated miRNAs in cervical cancer and their associated mechanism may promote the development of effective therapeutic approaches. miRNA-889-3p (miR-889) serves crucial roles in esophageal squamous cell carcinoma and hepatocellular carcinoma. However, to the best of our knowledge, no studies concerning the relationship between miR-889 and cervical cancer were performed. The aims of this study were to measure miR-889 expression in cervical cancer and to examine the potential effects of miR-889 in cervical cancer development on a molecular level to provide potential clinical insight. The present study revealed that miR-889 was downregulated in cervical cancer tissues and cell lines. Reduced miR-889 expression was significantly associated with International Federation of Gynecology and Obstetrics cancer staging and with lymph node metastasis. In addition, miR-889 overexpression reduced cervical cancer cell viability and invasive ability. Using bioinformatics analysis, fibroblast growth factor receptor 2 (FGFR2) was predicted to be a potential target of miR-889, which was confirmed using luciferase reporter assay. Reverse transcription-quantitative PCR and western blot analysis results suggested that miR-889 overexpression decreased FGFR2 expression in cervical cancer cells at the mRNA and the protein level, respectively. Conversely, FGFR2 silencing using small interfering RNA imitated the tumor suppressive effects of miR-889 overexpression in cervical cancer cells, which was successfully reversed by plasmid-facilitated FGFR2 overexpression. These observations demonstrated that miR-889 may serve tumor suppressive roles in cervical cancer by directly targeting FGFR2, which indicated that this miRNA may be a promising therapeutic target for patients with cervical cancer.

MiR-144-3p: a novel tumor suppressor targeting MAPK6 in cervical cancer.

Cervical cancer is the third most common gynecologic cancer in the world. Exploration of the molecular mechanism underlying cervical cancer pathogenesis will provide new insights into the development of novel therapies. In this study, we were aimed to characterize a novel miRNA in cervical cancer tumorigenesis. First, we measured the expressional change of miR-144-3p in clinical tissues and cancer cells. Second, we employed cell proliferation, cell migration, and invasion assays to understand its functional role in cervical cancer. Then, we confirmed in vitro findings in xenograft cancer model. Last, we mapped out a downstream target of miR-144-3p and validated its functional role in cancer cells. In the results, miR-144-3p was found significantly downregulated in cervical cancer cells and tissues. Over-expressing miR-144-3p suppressed cancer cells growth and metastasis. Consistent with in vitro results, over-expressing miR-144-3p led to tumor growth inhibition in vivo. Further on, MAPK6 was identified as an endogenous target of miR-144-3p in cervical cancer. Knocking down MAPK6 inhibited cervical cancer cells proliferation, migration, and invasion potential. Our investigation was the first time to report miR-144-3p as a tumor suppressive miRNA in cervical cancer. It inhibited tumor growth by targeting MAKP6. The newly identified signalling axis may serve as novel therapeutic targets to manage cervical cancer.

Optimal subset of signature miRNAs consisting of 7miRNAs that can serve as a novel diagnostic and prognostic predictor for the progression of cervical cancer.

Cervical cancer is the second most commonly diagnosed cancer in women. Novel prognostic biomarkers are required to predict the progression of cervical cancer. Cervical cancer expression data were obtained from The Cancer Genome Atlas (TCGA) database. MicroRNAs (miRNAs) significantly differentially expressed between early- and advanced-stage samples were identified by expression analysis. An optimal subset of signature miRNAs for pathologic stage prediction was delineated using the random forest algorithm and was used for the construction of a cervical cancer-specific support vector machine (SVM) classifier. The roles of signature miRNAs in cervical cancer were analyzed by functional annotation. In total, 44 significantly differentially expressed miRNAs were identified. An optimal subset of 7 signature miRNAs was identified, including hsa-miR-144, hsa-miR-147b, hsa-miR-218-2, hsa-miR-425, hsa-miR-451, hsa-miR-483 and hsa-miR-486. The signature miRNAs were used to construct an SVM classifier and exhibited a good performance in predicting pathologic stages of samples. SVM classification was found to be an independent prognostic factor. Functional enrichment analysis indicated that these signature miRNAs are involved in tumorigenesis. In conclusion, the subset of signature miRNAs could potentially serve as a novel diagnostic and prognostic predictor for cervical cancer.

MicroRNA-377 Targets Zinc Finger E-box-Binding Homeobox 2 to Inhibit Cell Proliferation and Invasion of Cervical Cancer.

A large number of microRNAs (miRNAs) are aberrantly expressed in cervical cancer and play crucial roles in the onset and progression of cervical cancer by acting as either an oncogene or a tumor suppressor. Therefore, investigation of the expression, biological roles, and underlying mechanisms of miRNAs in cervical cancer might provide valuable therapeutic targets in the treatment for patients with this disease. In this study, miRNA-377 (miR-377) was downregulated in cervical cancer tissues and cell lines. Decreased miR-377 expression was strongly correlated with the International Federation of Gynecology and Obstetrics (FIGO) stage, lymph node metastasis, and distant metastasis in patients with cervical cancer. Enhanced expression of miR-377 prohibited cell proliferation and invasion in cervical cancer. Bioinformatics analysis predicted that zinc finger E-box-binding homeobox 2 (ZEB2) was a potential target of miR-377. Subsequent experiments confirmed that ZEB2 is a direct target gene of miR-377 in cervical cancer. In addition, ZEB2 was overexpressed in cervical cancer tissues and was inversely related with miR-377 levels. Furthermore, the suppressive effects of miR-377 on cervical cancer proliferation and invasion were rescued by restored ZEB2 expression. Overall, our findings indicated that miR-377 decreases proliferation and invasion of cervical cancer cells by directly targeting ZEB2 and provides novel evidence of miR-377 as a novel therapeutic strategy for the therapy of patients with this malignancy.

Reference MicroRNAs for RT-qPCR Assays in Cervical Cancer Patients and Their Application to Studies of HPV16 and Hypoxia Biomarkers

MicroRNA (miRNA) expressions in tumor biopsies have shown potential as biomarkers in cervical cancer, but suitable reference RNAs for normalization of reverse transcription quantitative polymerase chain reaction (RT-qPCR) assays in patient cohorts with different clinicopathological characteristics are not available. We aimed to identify the optimal reference miRNAs and apply these to investigate the potential of miR-9-5p as human papilloma virus (HPV) 16 biomarker and miR-210-3p as hypoxia biomarker in cervical cancer. Candidate reference miRNAs were preselected in sequencing data of 90 patients and ranked in a stability analysis by RefFinder. A selection of the most stable miRNAs was evaluated by geNorm and NormFinder analyses of RT-qPCR data of 29 patients. U6 small nuclear RNA (RNU6) was also included in the evaluation. MiR-9-5p and miR-210-3p expression was assessed by RT-qPCR in 45 and 65 patients, respectively. Nine candidates were preselected in the sequencing data after excluding those associated with clinical markers, HPV type, hypoxia status, suboptimal expression levels, and low stability. In RT-qPCR assays, the combination of miR-151-5p, miR-152-3p, and miR-423-3p was identified as the most stable normalization factor across clinical markers, HPV type, and hypoxia status. RNU6 showed poor stability. By applying the optimal reference miRNAs, higher miR-9-5p expression in HPV16- than HPV18-positive tumors and higher miR-210-3p expression in more hypoxic than less hypoxic tumors were found in accordance with the sequencing data. MiR-210-3p was associated with poor outcome by both sequencing and RT-qPCR assays. In conclusion, miR-151-5p, miR-152-3p, and miR-423-3p are suitable reference miRNAs in cervical cancer. MiR-9-5p and miR-210-3p are promising HPV16 and hypoxia biomarkers, respectively.

MiRNA-641 inhibits the proliferation, migration, and invasion and induces apoptosis of cervical cancer cells by directly targeting ZEB1.

BackgroundmiRNAs have been found to be dysregulated in cervical cancer. The dysregulation of miRNA has been implicated in cervical carcinogenesis and progression. Therefore, further studies of the specific roles of deregulated miRNAs in cervical cancer and underlying molecular mechanisms may facilitate the identification of novel therapeutic techniques for patients with this disease. miRNA-641 (miR-641) was previously reported to serve an important role in lung cancer. However, the expression pattern and roles of miR-641 in cervical cancer remain unclear.MethodIn this study, the expression level of miR-641 in cervical cancer tissues and cell lines was detected using RT-qPCR. The influence of miR-641 upregulation in cervical cancer cell proliferation, apoptosis, migration and invasion was evaluated using CCK-8 assay, flow cytometry assay, migration and invasion assays, respectively. In vivo tumor growth assay was utilized to determine the effect of miR-641 overexpression in the tumor growth of cervical cancer cells in vivo. The molecular mechanisms underlying the action of miR-641 in cervical cancer cells were also explored.ResultsWe found that miR-641 expression was obviously decreased in cervical cancer tissues and cell lines, which strongly correlated with the International Federation of Gynecology and Obstetrics stage and lymph node metastasis. Upregulation of miR-641 inhibited cell proliferation, induced apoptosis, and reduced metastasis in cervical cancer. Additionally, bioinformatics analysis predicted ZEB1 as a novel target gene of miR-641. Notably, luciferase reporter assay, RT-qPCR, and Western blot analysis revealed that miR-641 decreased ZEB1 expression in cervical cancer cells by directly targeting its 3′-untranslated region. Furthermore, ZEB1 was upregulated in cervical cancer tissues, which was negatively correlated with miR-641 expression. Moreover, recovered ZEB1 expression attenuated the tumor suppressive action of miR-641 overexpression in the malignant phenotypes of cervical cancer cells. Besides, miR-641 could hinder cervical cancer tumor growth in vivo by inhibiting ZEB1.ConclusionThese results indicate that miR-641 has tumor suppressive roles in the development of cervical cancer by directly targeting ZEB1, suggesting that miR-641 is a novel, effective therapeutic target for treating patients with this disease.

Suppression of miR-22, a tumor suppressor in cervical cancer, by human papillomavirus 16 E6 via a p53/miR-22/HDAC6 pathway.

MicroRNAs (miRNAs) are small non-coding RNAs that function to down-regulate gene expression involving in various cellular processes related to carcinogenesis. Recently, miR-22 was identified as a tumor-suppressing miRNA in many human cancers. However, the regulatory mechanism and the specific function of this miRNA in cervical cancer remain unclear. In the present study, we carried out gene transfection, western blot and quantitative RT-PCR to explore the regulatory mechanism and the functional role of miR-22 in cervical cancer. We verified that miR-22 was down-regulated in cervical cancer tissues and cervical cancer cell lines relative to matched non-tumor tissues and normal human cervical keratinocyte line (HCK1T). By contrast, histone deacetylase 6 (HDAC6) was inversely correlated with miR-22 in both cervical tissues and cancer cell lines. Mechanically, HDAC6 was down-regulated by miR-22 at the post-transcriptional level, via a specific target site within the 3’UTR, identified by a luciferase reporter assay. Moreover, we also showed that the correlation between miR-22 and HDAC6 expression was regulated by an E6/p53 pathway in HCK1Ts expressing HPV16 E6. For functional study, an ectopic expression of miR-22 could inhibit cell proliferation and migration, and could induce apoptosis of cervical cancer cell lines. These findings demonstrated that miR-22 was down-regulated in cervical cancer and inversely collated with its downstream target HDAC6. MiR-22 acts as tumor suppressor by inhibiting proliferation and migration, and by inducing apoptosis of cervical cancer cell lines by targeting the 3’UTR of HDAC6. This newly identified E6/p53/miR-22/HDAC6 regulatory network might be a candidate therapeutic target for cervical cancer.

Identification of miRNAs in cervical mucus as a novel diagnostic marker for cervical neoplasia

microRNAs (miRNAs) play important roles in regulation of gene expression during cervical carcinogenesis. We investigated expression profiles of miRNAs in cervical cancer and its precursor lesions by utilizing cervical mucus. Cervical mucus was collected from 230 patients with a normal cervix, cervical intraepithelial neoplasia (CIN), squamous cell carcinoma (SCC), or adenocarcinoma (AD). The levels of miRNA in the mucus were quantified by miRNA array and real-time reverse-transcriptase polymerase chain reaction (RT-PCR). The performance for detecting diseases was statistically analysed. The expression of miRNAs was further validated in the surgical tissues of enrolled patients. Four miRNAs (miR-126-3p, -20b-5p, -451a, and -144-3p) were significantly up-regulated in SCC and AD compared with normal, and their expression levels correlated with disease severity and high-risk human papillomavirus infection. Receiver operating characteristic curve analyses revealed that the area under the curve values for miR-126-3p, -20b-5p, -451a, and -144-3p were 0.89, 0.90, 0.94, and 0.93, respectively, for SCC plus AD compared with normal, showing high accuracy of cancer detection. Real-time RT-PCR analyses confirmed the expression of these four miRNAs in frozen tissues from cervical cancer. miR-126-3p, -20b-5p, -451a, and -144-3p in cervical mucus are promising biomarkers for cervical cancer and high-grade CINs.

MiR-17-5p promotes cervical cancer cell proliferation and metastasis by targeting transforming growth factor-β receptor 2.

MicroRNAs (miRNAs) play critical roles in post-translational gene expression. The aim of the current study was to investigate the effects of miR-17-5p in cervical cancer. Fifteen clinical cervical cancer tissue samples, as well as their paired adjacent noncancerous tissues, were collected. The microarray was performed to identify differential miRNAs in cervical cancer. Luciferase reporter assay was conducted to identify the target gene of selected miRNA. SiHa was transfected with mimics, inhibitors as well as negative controls of miR-17-5p and Targeting Transforming Growth Factor-β Receptor 2 (TGFBR2) open reading frame or siRNA. Cell counting kit-8 (CCK-8) assay and transwell experiment were performed to detect the proliferation rate and metastasis, respectively. Western blotting and quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) analysis were used to analyze TGFBR2 expression. Balb/c nude mice were utilized to verify the effect of miR-17-5p in vivo. Microarray analysis identified miR-17-5p as our interesting miRNA, and luciferase reporter assay identified TGFBR2 as its target gene. MiR-17-5p overexpression significantly enhanced cervical cancer cell proliferation and metastasis. In-vivo study also verified that miR-17-5p overexpression stimulated cervical cancer growth. MiR-17-5p enhances cervical cancer proliferation and metastasis via targeting TGFBR2. It is proposed that targeting miR-17-5p may be a promising therapeutic approach for cervical cancer.

WITHDRAWN: Optimal subset of feature miRNAs consisting of 7 miRNAs that can serve as a novel diagnostic and prognostic predictor for the progression of cervical cancer

// Shanshan Qin 1 , Yingchun Gao 1 , Yijun Yang 1 , Juanpeng Yu 1 , Fei Meng 1 , Ting Zhang 1 and Can Shi 1 1 Department of Obstetrics and Gynecology, Huai'an First People’s Hospital, Nanjing Medical University, Huai'an, Jiangsu 223300, P.R. China Correspondence to: Can Shi, email: shican2015@126.com Keywords: cervical cancer; biomarker; miRNA; prognosis; progression Received: September 07, 2017 Accepted: November 13, 2017 Published: January 02, 2018 ABSTRACT Objective: Cervical cancer is the second most commonly diagnosed cancer in women. Novel prognostic biomarkers are needed to predict the progression of cervical cancer. Results: In total, 44 significantly differentially expressed miRNAs were identified. An optimal subset of 7 feature miRNAs was identified, including hsa-miR-144, hsa-miR-147b, hsa-miR-218-2, hsa-miR-425, hsa-miR-451, hsa-miR-483, and hsa-miR-486. The feature miRNAs were used to construct an SVM classifier and showed a good performance in predicting pathologic stages of samples. SVM classification was found to be an independent prognostic factor. Functional enrichment analysis indicated that these feature miRNAs are involved in tumorigenesis. Materials and Methods: Cervical cancer expression data were obtained from the Cancer Genome Atlas database. MicroRNAs (miRNAs) significantly differentially expressed between early- and advanced-stage samples were identified by expression analysis. An optimal subset of feature miRNAs for pathologic stage prediction was delineated using the random forest algorithm and was used for the construction of a cervical cancer-specific support vector machine (SVM) classifier. The roles of feature miRNAs in cervical cancer were analyzed by functional annotation. Conclusions: The subset of feature miRNAs could potentially serve as a novel diagnostic and prognostic predictor for cervical cancer.