miR-1207-3p Is a Novel Prognostic Biomarker of Prostate Cancer

Circ_0021350 plays an oncogene role by regulating miR-1207-3p/PIK3R3 in glioblastoma

BACKGROUND

Glioblastoma (GBM) is the most malignant glioma, with poor survival rates and prognosis. Several studies have reported the abnormal expression of circular RNAs (circRNAs) and their functions in the malignant biological behavior of GBM. However, such research is still in the preliminary stages, and further study is needed to confirm the therapeutic potential of circRNAs in GBM.

METHODS

RNA-seq was performed using four tumor tissues from patients with GBM and their adjacent non-tumor brain tissues to screen differentially expressed circRNAs. Fluorescence in situ hybridization assay was used to examine the location of circ_0021350 in glioma cells. In addition, a series of biological function assays were employed to verify the oncogenic role of circ_0021350 in GBM. Quantitative reverse transcription PCR was used to examine circular, micro- (miRNA), and messenger RNA (mRNA) levels. Furthermore, dual-luciferase reporter, RNA pull-down, and RNA binding protein immunoprecipitation assays were applied to verify the interaction between circ_0021350 and its downstream effectors.

RESULTS

Circ_0021350 was significantly elevated in GBM tissues and glioma cells. Overexpression of circ_0021350 promoted glioma cell proliferation and metastatic ability; silencing of circ_0021350 had the opposite effect. Mechanistic analysis revealed that circ_0021350 sponged miR-1207-3p to regulate PIK3R3, whose overexpression reversed the reduction in the malignant biological behavior of glioma cells caused by silencing circ_0021350.

CONCLUSION

Our findings suggest that circ_0021350 is an oncogenic circRNA in GBM, and the circ_0021350/miR-1207-3p/PIK3R3 axis may serve as a potential therapeutic target in GBM treatment.

MiR-1207-5p targets PYCR1 to inhibit the progression of prostate cancer

Prostate cancer, the most common non-cutaneous male cancer, is a public health problem with a third prevalence worldwide. PYCR1 and miR-1207-5p dysregulations were found in cancer progression. Our study aims to reveal the biological role of miR-1207-5p-PYCR1 axis in prostate cancer progression. First, we investigated the expression of miR-1207-5p in prostate cancer tissues and cell lines by RT-qPCR. Next, we confirmed miR-1207-5p targeting PYCR1 by luciferase assay. CCK-8 assay, BrdU assay, flow cytometry, and tanswell assay were applied for examining cell proliferation, apoptosis, and invasion in prostate cancer cells, respectively. In the present study, decreased miR-1207-5p expression was obviously observed in prostate cancer tissues and cells. Upregulation of miR-1207-5p hampered cellular proliferation and invasion, while enhanced cellular apoptosis. In addition, upregulation of PYCR1 elevated cell proliferation and invasion, but repressed apoptosis of prostate cancer cells. Moreover, miR-1207-5p inhibited the expression of PYCR1 to repress prostate cancer tumorigenesis. MiR-1207-5p inhibited the expression of PYCR1 to repress the progression of prostate cancer by inhibiting cell growth and elevating cell apoptosis. Overall, our study clarifies the biological role of miR-1207-5p-PYCR1 axis in prostate cancer progression, which might be effective biomarkers for clinical treatment of prostate cancer.

LncRNA-PVT1 indicates a poor prognosis and promotes angiogenesis via activating the HNF1B/EMT axis in glioma

Recent studies identified that long non-coding RNAs (lncRNAs) exhibited critical roles in tumor migration and invasion. However, the roles of lncRNAs in glioma remain unclear. The aim of this study was to uncover the underlying mechanisms of glioma progression and provide potential therapeutic targets for its treatment in clinic. Our microarray study showed that lncRNA-PVT1 was significantly upregulated in glioma tissues and played an important role in cell proliferation, migration, invasion and angiogenesis. Our data showed that the expression of lncRNA-PVT1 was increased obviously and associated with advanced tumor stage, metastasis, invasion ability, and poor prognosis in glioma patients. Up-regulation of lncRNA-PVT1 was observed to promote glioma cells proliferation, and invasion abilities in vitro as well as tumor growth in vivo by regulating miR-1207-3p expression. Online software (TargetScan, miRDB and miR TarBase) were used to predict the regulating mechanisms of lncRNA-PVT1, miR-1207-3p and HNF1B, which were validated by dual-luciferase reporter gene system. In vivo tumor-bearing mice models were established to validate the cellular results. Therefore, we suggested that lncRNA-PVT1/miR-1207-3p/HNF1B axis might play critical roles in glioma progression, indicating that lncRNA-PVT1/miR-1207-3p/HNF1B signaling axis may serve as novel molecular targets for glioma prevention and treatment.

MicroRNA-1205 Regulation of FRYL in Prostate Cancer

High mortality rates of prostate cancer (PCa) are associated with metastatic castration-resistant prostate cancer (CRPC) due to the maintenance of androgen receptor (AR) signaling despite androgen deprivation therapies (ADTs). The 8q24 chromosomal locus is a region of very high PCa susceptibility that carries genetic variants associated with high risk of PCa incidence. This region also carries frequent amplifications of the PVT1 gene, a non-protein coding gene that encodes a cluster of microRNAs including, microRNA-1205 (miR-1205), which are largely understudied. Herein, we demonstrate that miR-1205 is underexpressed in PCa cells and tissues and suppresses CRPC tumors in vivo. To characterize the molecular pathway, we identified and validated fry-like (FRYL) as a direct molecular target of miR-1205 and observed its overexpression in PCa cells and tissues. FRYL is predicted to regulate dendritic branching, which led to the investigation of FRYL in neuroendocrine PCa (NEPC). Resistance toward ADT leads to the progression of treatment related NEPC often characterized by PCa neuroendocrine differentiation (NED), however, this mechanism is poorly understood. Underexpression of miR-1205 is observed when NED is induced in vitro and inhibition of miR-1205 leads to increased expression of NED markers. However, while FRYL is overexpressed during NED, FRYL knockdown did not reduce NED, therefore revealing that miR-1205 induces NED independently of FRYL.

Exploring Prostate Cancer Patients' Interest and Preferences for Receiving Genetic Risk Information About Cancer Aggressiveness

The number of cases of aggressive prostate cancer is increasing. Differentiating between aggressive and indolent cases has resulted in increased difficulty for the physician and patient to decide on the best treatment option. Due to this challenge, efforts are underway to profile genetic risk for prostate cancer aggressiveness, which may help physicians and patients at risk for developing aggressive prostate cancer to select an appropriate treatment option. This study explores patients’ interest in receiving genetic results, preference for how genetic risk information should be communicated, and willingness to share results with adult male first-degree relatives (FDRs). A nine-item survey was adapted to assess their beliefs and attitudes about genetic testing for prostate cancer aggressiveness. In addition, participants (n = 50) responded to hypothetical scenarios and questions associated with perceived importance of risk disclosure, preferences for receiving genetic risk information, and sharing of results with FDRs. As the hypothetical risk estimate for aggressive prostate cancer increased, patients’ willingness to receive genetic risk information increased. This study found that most patients preferred receiving genetic risk education in the form of a DVD (76%), one-page informational sheet (75%), or educational booklet (70%). Almost all patients (98%) reported that they would be willing to share their test results with FDRs. The results of this study highlight prostate cancer patients’ desire to receive and share genetic risk information. Future research should focus on assessing the long-term benefits of receiving genetic information for prostate cancer patients and implications of sharing this information with FDRs.

Expression of miR-451a in Prostate Cancer and Its Effect on Prognosis

Background:

To investigate the expression of miR-451a in prostate cancer tissues and its effect on prognosis.

Methods:

Each of 78 specimens of prostate cancer tissues and corresponding adjacent normal tissues were collected from patients in Changshu Hospital Affiliated to Soochow University, Changshu, China from Apr 2014 to Jun 2015. Real-time quantitative RT-PCR (qRT-PCR) was used to detect the expression of miR-451a in tissues. The relationship between the expression of miR-451a and clinical pathological parameters was analyzed. The median expression of miR-451a in the experimental group was used to distinguish the high and low expressions of miR-451a in the experimental group. Kaplan-Meier was used to analyze the survival of miR-451a high and low expression groups.

Results:

The expressions of miR-451a in the patient’s tissues and serum were decreased, and the correlation analysis found that they were positively correlated. ROC curve analysis showed that miR-451a had a high clinical value in the diagnosis of prostate cancer and the area under the curve was 0.921. The incidence of stage III+IV lymph node metastasis, Gleason score of >7 points and a serum Prostate-specific antigen (PSA) level of >20 ng/ml in patients of the low expression group increased significantly. The 5-yr survival rate of patients with low expression was significantly lower than that of those with high expression (P=0.005). MiR-451a was an independent factor affecting the prognosis of patients.

Conclusion:

miR-451a is lowly expressed in prostate cancer, and patients with low expression have a poor prognosis.

Identification and analysis of survival-associated ceRNA triplets in prostate adenocarcinoma

Prostate adenocarcinoma (PRAD) is one of the most common causes of cancer-associated mortality worldwide. Recent evidence has emphasized the role of competitive endogenous RNAs (ceRNA) in prostate cancer. However, the current understanding of the roles that ceRNAs play in survival-associated PRAD remains in its infancy. In the present study, a PRAD-specific ceRNA network was constructed by integrating long non-coding RNA (lncRNA)-microRNA (miRNA)-gene interactions using experimental and computational methods, as well as expression correlations from The Cancer Genome Atlas database. The topological features of the ceRNA network were then analyzed and the PRAD-risk lncRNAs were compared with non-risk lncRNAs within this network. It was revealed that PRAD-risk lncRNAs had a higher degree, closeness and betweenness centrality, but also had the shortest path length. Finally, 42 significant PRAD-survival-associated triplets were identified. Notably, these triplets may form a compacted subnetwork composed of only 25 nodes (5 miRNAs, 4 lncRNAs and 16 genes) and 32 edges, indicating that some nodes were involved in many triplets. Among this subnetwork, mir-21 indicated the highest degree centrality and was demonstrated to exert its oncogenic effects in prostate tumors by downregulating transforming growth factor β receptor 2 (TGFBR2). Two triplets (MIR22HG_hsa-mir-21_TGFBR2 and MIR22HG_hsa-mir-21_BCL2) were finally identified; not only were they significantly associated with PRAD survival but they also had the highest average degree in the identified subnetwork. The results from the present study provide further insights into the understanding of the potential roles and interactions of ceRNA triplets and potential prognosis markers for PRAD.

The role of miRNAs as biomarkers in prostate cancer

There is an urged need of non-invasive biomarkers for the implementation of precision medicine. These biomarkers are required to these days for improving prostate cancer (PCa) screening, treatment or stratification in current clinical strategies. There are several commercial kits (Oncotype DX genomic prostate score^®, Prolaris^®, among others) that use genomic changes, rearrangement or even non-coding RNA events. However, none of them are currently used in the routine clinical practice. Many recent studies indicate that miRNAs are relevant molecules (small single-stranded non-coding RNAs that regulate gene expression of more than 30% of human genes) to be implement non-invasive biomarkers. However, contrasting to others tumors, such as breast cancer where miR-21 seems to be consistently upregulated; PCa data are controversial. Here we reported an extended revision about the role of miRNAs in PCa including data of AR signaling, cell cycle, EMT process, CSCs regulation and even the role of miRNAs as PCa diagnostic, prognostic and predictive tool. It is known that current biomedical research uses big-data analysis like Next Generation Sequencing (NGS) analysis. We also conducted an extensive online search, including the main platforms and kits for miRNAs massive analysis (like MiSeq, Nextseq 550, or Ion S5™ systems) indicating their pros, cons and including pre-analytical and analytical issues of miRNA studies.

Interactions of PVT1 and CASC11 on Prostate Cancer Risk in African Americans

BACKGROUND

African American (AA) men have a higher risk of developing prostate cancer than white men. SNPs are known to play an important role in developing prostate cancer. The impact of PVT1 and its neighborhood genes (CASC11 and MYC) on prostate cancer risk are getting more attention recently. The interactions among these three genes associated with prostate cancer risk are understudied, especially for AA men. The objective of this study is to investigate SNP-SNP interactions in the CASC11-MYC-PVT1 region associated with prostate cancer risk in AA men.

METHODS

We evaluated 205 SNPs using the 2,253 prostate cancer patients and 2,423 controls and applied multiphase (discovery-validation) design. In addition to SNP individual effects, SNP-SNP interactions were evaluated using the SNP Interaction Pattern Identifier, which assesses 45 patterns.

RESULTS

Three SNPs (rs9642880, rs16902359, and rs12680047) and 79 SNP-SNP pairs were significantly associated with prostate cancer risk. These two SNPs (rs16902359 and rs9642880) in CASC11 interacted frequently with other SNPs with 56 and 9 pairs, respectively. We identified the novel interaction of CASC11-PVT1, which is the most common gene interaction (70%) in the top 79 pairs. Several top SNP interactions have a moderate to large effect size (OR, 0.27-0.68) and have a higher prediction power to prostate cancer risk than SNP individual effects.

CONCLUSIONS

Novel SNP-SNP interactions in the CASC11-MYC-PVT1 region have a larger impact than SNP individual effects on prostate cancer risk in AA men.

IMPACT

This gene-gene interaction between CASC11 and PVT1 can provide valuable information to reveal potential biological mechanisms of prostate cancer development.

Tristetraprolin Is a Prognostic Biomarker for Poor Outcomes among Patients with Low-Grade Prostate Cancer

Background: We studied the utility of the tumor suppressor Tristetraprolin (TTP, ZFP36) as a clinically relevant biomarker of aggressive disease in prostate cancer patients after radical prostatectomy (RP).Methods: TTP RNA expression was measured in an RP cohort of patients treated at Moffitt Cancer Center (MCC) and obtained from six publically available RP datasets with biochemical recurrence (BCR; total n = 1,394) and/or metastatic outcome data (total n = 1,222). TTP protein expression was measured by immunohistochemistry in a tissue microarray of 153 MCC RP samples. The time to BCR or metastasis based on TTP RNA or protein levels was calculated using the Kaplan-Meier analysis. Univariable and multivariable Cox proportional hazard models were performed on multiple cohorts to evaluate if TTP is a clinically relevant biomarker and to assess if TTP improves upon the Cancer of the Prostate Risk Assessment postsurgical (CAPRA-S) score for predicting clinical outcomes.Results: In all of the RP patient cohorts, prostate cancer with low TTP RNA or protein levels had decreased time to BCR or metastasis versus TTP-high tumors. Further, the decreased time to BCR in TTP-low prostate cancer was more pronounced in low-grade tumors. Finally, pooled survival analysis suggests that TTP RNA expression provides independent information beyond CAPRA-S to predict BCR.Conclusions: TTP is a promising prostate cancer biomarker for predicting which RP patients will have poor outcomes, especially for low-grade prostate cancer patients.Impact: This study suggests that TTP RNA expression can be used to enhance the accuracy of CAPRA-S to predict outcomes in patients treated with RP. Cancer Epidemiol Biomarkers Prev; 27(11); 1376-83. ©2018 AACR.

Knockdown of Cripto-1 inhibits the proliferation, migration, invasion, and angiogenesis in prostate carcinoma cells

Cripto-1 (CR-1) is a member of the epidermal growth factor-Cripto-1/FRL1/Cryptic gene family that plays a key role in the various malignant cancers. However, the role of CR-1 in prostate carcinoma (PCa) remains limited. The expression of CR-1 was down-regulated by small interfering RNA (siRNA). Western blot measured the expression levels of CR-1 and some related proteins. We performed Cell Counting Kit-8, 5-ethynyl-2-deoxyuridine (EdU) incorporation assay and flow cytometry to detect the cellular proliferation and cycle. The transwell assay was used to observe cellular migration and invasion. The ability of angiogenesis was evaluated by tube formation assay. Our results showed that CR-1 knockdown markedly inhibited cell proliferation and induced cycle arrest in G1 phase, as p21 and p27 were up-regulated, whereas cyclin D1 and cyclin E1 were diminished. Moreover, silencing of CR-1 dramatically inhibited cell migration and invasion, repressed matrix metalloproteinases, and disturbed epithelial-mesenchymal transition. CR-1 siRNA suppressed the secreted level of vascular endothelial growth factor, and reduced protein level of Vascular endothelial growth factor receptor 2. We further found that decreased CR-1 expression inhibited FAK/Src/PI3K and Wnt/b-catenin signalling in PCa cells. These results suggested CR-1 might be served as an effective therapeutic target in PCa.

The potential of microRNAs as human prostate cancer biomarkers: A meta-analysis of related studies

Prostate cancer (PC) is a very important kind of male malignancies. When PC evolves into a stage of hormone resistance or metastasis, the fatality rate is very high. Currently, discoveries and advances in miRNAs as biomarkers have opened the potential for the diagnosis of PC, especially early diagnosis. miRNAs not only can noninvasively or minimally invasively identify PC, but also can provide the data for optimization and personalization of therapy. Moreover, miRNAs have been shown to play an important role to predict prognosis of PC. The purpose of this meta‐analysis is to integrate the currently published expression profile data of miRNAs in PC, and evaluate the value of miRNAs as biomarkers for PC. All of relevant records were selected via electronic databases: Pubmed, Embase, Cochrane, and CNKI based on the assessment of title, abstract, and full text. we extracted mean ± SD or fold change of miRNAs expression levels in PC versus BPH or normal controls. Pooled hazard ratios (HRs) with 95% confidence intervals (CI) for overall survival (OS) and recurrence‐free survival (RFS), were also calculated to detect the relationship between high miRNAs expression and PC prognosis. Selected 104 articles were published in 2007‐2017. According to the inclusion criteria, 104 records were included for this meta‐analysis. The pooled or stratified analyze showed 10 up‐regulated miRNAs (miR‐18a, miR‐34a, miR‐106b, miR‐141, miR‐182, miR‐183, miR‐200a/b, miR‐301a, and miR‐375) and 14 down‐regulated miRNAs (miR‐1, miR‐23b/27b, miR‐30c, miR‐99b, miR‐139‐5p, miR‐152, miR‐187, miR‐204, miR‐205, miR‐224, miR‐452, miR‐505, and let‐7c) had relatively good diagnostic and predictive potential to discriminate PC from BPH/normal controls. Furthermore, high expression of miR‐32 and low expression of let‐7c could be used to differentiate metastatic PC from local/primary PC. Additional interesting findings were that the expression profiles of five miRNAs (miR‐21, miR‐30c, miR‐129, miR‐145, and let‐7c) could predict poor RFS of PC, while the evaluation of miR‐375 was associated with worse OS. miRNAs are important regulators in PC progression. Our results indicate that miRNAs are suitable for predicting the different stages of PC. The detection of miRNAs is an effective way to control patient's prognosis and evaluate therapeutic efficacy. However, large‐scale detections based on common clinical guidelines are still necessary to further validate our conclusions, due to the bias induced by molecular heterogeneity and differences in study design and detection methods.

Tissue-Based MicroRNAs as Predictors of Biochemical Recurrence after Radical Prostatectomy: What Can We Learn from Past Studies?

With the increasing understanding of the molecular mechanism of the microRNAs (miRNAs) in prostate cancer (PCa), the predictive potential of miRNAs has received more attention by clinicians and laboratory scientists. Compared with the traditional prognostic tools based on clinicopathological variables, including the prostate-specific antigen, miRNAs may be helpful novel molecular biomarkers of biochemical recurrence for a more accurate risk stratification of PCa patients after radical prostatectomy and may contribute to personalized treatment. Tissue samples from prostatectomy specimens are easily available for miRNA isolation. Numerous studies from different countries have investigated the role of tissue-miRNAs as independent predictors of disease recurrence, either alone or in combination with other clinicopathological factors. For this purpose, a PubMed search was performed for articles published between 2008 and 2017. We compiled a profile of dysregulated miRNAs as potential predictors of biochemical recurrence and discussed their current clinical relevance. Because of differences in analytics, insufficient power and the heterogeneity of studies, and different statistical evaluation methods, limited consistency in results was obvious. Prospective multi-institutional studies with larger sample sizes, harmonized analytics, well-structured external validations, and reasonable study designs are necessary to assess the real prognostic information of miRNAs, in combination with conventional clinicopathological factors, as predictors of biochemical recurrence.

A novel microRNA-1207-3p/FNDC1/FN1/AR regulatory pathway in prostate cancer

Prostate cancer (PCa) is the second most common cause of cancer-specific deaths in the U.S. Unfortunately, the underlying molecular mechanisms for its development and progression remain unclear. Studies have established that microRNAs (miRNAs) are dysregulated in PCa. The intron-derived microRNA-1207-3p (miR-1207-3p) is encoded at the non-protein coding gene locus PVT1 on the 8q24 human chromosomal region, an established PCa susceptibility locus. However, miR-1207-3p in PCa had not previously been investigated. Therefore, we explored if miR-1207-3p plays any regulatory role in PCa. We discovered that miR-1207-3p is significantly underexpressed in PCa cell lines in comparison to normal prostate epithelial cells, and that increased expression of microRNA-1207-3p in PCa cells significantly inhibits proliferation, migration, and induces apoptosis via direct molecular targeting of fibronectin type III domain containing 1 (FNDC1). Our studies also revealed significant overexpression of FNDC1, fibronectin (FN1) and the androgen receptor (AR) in human PCa cell lines as well as tissues, and FNDC1, FN1, and AR positively correlate with aggressive PCa. These findings, recently published in Experimental Cell Research, are the first to describe a novel miR-1207-3p/FNDC1/FN1/AR novel regulatory pathway in PCa.

Differential expression of miR-34b and androgen receptor pathway regulate prostate cancer aggressiveness between African-Americans and Caucasians

African-Americans are diagnosed with more aggressive prostate cancers and have worse survival than Caucasians, however a comprehensive understanding of this health disparity remains unclear. To clarify the mechanisms leading to this disparity, we analyzed the potential involvement of miR-34b expression in African-Americans and Caucasians. miR-34b functions as a tumor suppressor and has a multi-functional role, through regulation of cell proliferation, cell cycle and apoptosis. We found that miR-34b expression is lower in human prostate cancer tissues from African-Americans compared to Caucasians. DNA hypermethylation of the miR-34b-3p promoter region showed significantly higher methylation in prostate cancer compared to normal samples. We then sequenced the promoter region of miR-34b-3p and found a chromosomal deletion in miR-34b in African-American prostate cancer cell line (MDA-PCA-2b) and not in Caucasian cell line (DU-145). We found that AR and ETV1 genes are differentially expressed in MDA-PCa-2b and DU-145 cells after overexpression of miR-34b. Direct interaction of miR-34b with the 3' untranslated region of AR and ETV1 was validated by luciferase reporter assay. We found that miR-34b downregulation in African-Americans is inversely correlated with high AR levels that lead to increased cell proliferation. Overexpression of miR-34b in cell lines showed higher inhibition of cell proliferation, apoptosis and G1 arrest in the African-American cells (MDA-PCa-2b) compared to Caucasian cell line (DU-145). Taken together, our results show that differential expression of miR-34b and AR are associated with prostate cancer aggressiveness in African-Americans.