Prostate Cancer Cell Invasion Research Articles

ZFP36 Inhibits Tumor Progression of Human Prostate Cancer by Targeting CDK6 and Oxidative Stress.

Background The expression of ZFP36 in previous study was reduced in prostate cancer (PCa) tissues as compared to benign prostate tissues, indicating the potential of ZFP36 as an auxiliary marker for PCa. Further evaluation was conducted in clinical samples for in vitro and in vivo experiments, to prove the potential possibility that ZFP36 dysregulation participated in the malignant phenotype of PCa, to determine its potential mechanism for tumor regulation, and to provide a new theoretical basis for gene therapy of PCa. Methods First, the expression of ZFP36 in prostate tissue and PCa tissue was explored, and the relationship between ZFP36 and clinical features of PCa patients was illustrated. Subsequently, the impact of ZFP36 on the biology of PCa cells and relevant downstream pathways of ZFP36's biological impact on PCa were elucidated. Finally, whether oxidative stress mediated the regulation of ZFP36 in PCa was verified by the determination of oxidative stress-related indicators and bioinformatics analysis. Results The downregulation of ZFP36 in PCa tissue had a positive correlation with high Gleason scores, advanced pathological stage, and biochemical recurrence. ZFP36 was identified as an independent prognostic factor for PCa patients' BCR-free survival (P = 0.022) by survival analysis. Following a subsequent experiment of function gain and loss, ZFP36 inhibited the proliferation, invasion, and migration in DU145 and 22RV1 cells and inhibits tumor growth in the mouse model. Additionally, high-throughput sequencing screened out CDK6 as the downstream target gene of ZFP36. Western blot/Q-PCR demonstrated that overexpression of ZFP36 could reduce the expression of CDK6 at both cellular and animal levels, and the dual-luciferase experiment and RIP experiment proved that CDK6 was the downstream target of ZFP36, indicating that CDK6 was a downstream target of ZFP36, which mediated tumor cell growth by blocking cell cycle at the G1 stage. Furthermore, ZFP36 inhibited oxidative stress in PCa cells. Conclusions In PCa, ZFP36 might be a tumor suppressor that regulated growth, invasion, and migration of PCa cells. The lately discovered ZFP36-CDK6 axis demonstrated the molecular mechanism of PCa progression to a certain extent which might act as a new possible therapeutic target of PCa therapy.

MicroRNA-145-5p inhibits prostate cancer bone metastatic by modulating the epithelial-mesenchymal transition.

ObjectiveTo investigate the effects of miRNA-145-5p on the tumor development and progression of prostate cancer (Pca) bone metastasis.MethodsLevels of miRNA-145-5p were assessed by real-time quantitative PCR in PC3 (bone metastatic Pca cells), 22RV1 (non-metastatic Pca cells), RWPE-1 (non-cancerous prostate epithelial cells) and Pca tissues collected from patients with and without bone metastases. The impact of miRNA-145-5p on cell proliferation was tested by CCK8 assay, colony formation assay and flow cytometric cell cycle analysis. Effects on invasion and migration of PC3 cells were determined by Transwell and wound healing assays. Western blotting, enzyme-linked immunosorbent assay, and flow cytometry apoptosis analyses were also performed to assess roles in metastasis.ResultsLevels of miRNA-145-5p were decreased in Pca bone metastases and miRNA-145-5p inhibited cell proliferation, migration and invasion. miRNA-145-5p inhibited the expression of basic fibroblast growth factor (bFGF), insulin-like growth factor (IGF) and transforming growth factor-β (TGF-β) in PC3 cells. miR-145-5p increased the expression of the epithelial marker E-cadherin and reduced the expression of matrix metalloproteinase 2 and 9 (MMP-2 and MMP-9). It was found that miRNA-145-5p mediated the epithelial-mesenchymal transition (EMT) and induced apoptosis.ConclusionsmiRNA-145-5p negatively regulated the EMT, inhibited Pca bone metastasis and promoted apoptosis in Pca bone metastasis. Mimicry of miRNA-145-5p action raises the possibility of a novel target for treating Pca with bone metastases.

MiR-114 Derived from Bone Marrow Mesenchymal Stem Cells Regulates the Metastasis of Prostate Cancer Cells by Targeting P53 Gene

Prostate cancer (PCa) in the elderly is a malignancy primary to the prostate and a common tumor in the male urogenital line. However, no effective treatment has been developed for prostate cancer. Previous studies have shown that BMSCs-derived miR-114 can inhibit tumor cell development. Therefore, we intend to determine the role of BMSCs-derived miR-114 and p53 in PCa. Human prostate cancer cells (LNCaP) and BMSCs were inoculated into 12-well plates. After interfering the expression of miR-114 in BMSCs, the culture medium was collected and used to treat LNCaP followed by analysis of cell behaviors. miR-114 inhibited p53 level in BMSC-derived exosomes, thereby inhibiting the proliferation, invasion and migration of PCa cells, and enhancing cell apoptosis. In conclusion, BMSCs-derived miR-114 inhibits the proliferation, migration, invasion and promotes apoptosis of prostate cancer cells by down-regulating p53.

Dietary stilbenes as modulators of specific miRNAs in prostate cancer.

Accumulated experimental data have suggested that natural plant products may be effective miRNA-modulating chemopreventive and therapeutic agents. Dietary polyphenols such as flavonoids, stilbenes, and lignans, among others, have been intensively studied for their miRNA-mediated cardioprotective, antioxidant, anti-inflammatory and anticancer properties. The aim of this review is to outline known stilbene-regulated miRNAs in cancer, with a special focus on the interplay between various miRNAs and MTA1 signaling in prostate cancer. MTA1 is an epigenetic reader and an oncogenic transcription factor that is overexpressed in advanced prostate cancer and metastasis. Not surprisingly, miRNAs that are linked to MTA1 affect cancer progression and the metastatic potential of cells. Studies led to the identification of MTA1-associated pro-oncogenic miRNAs, which are regulated by stilbenes such as resveratrol and pterostilbene. Specifically, it has been shown that inhibition of the activity of the MTA1 regulated oncogenic miR-17 family of miRNAs, miR-22, and miR-34a by stilbenes leads to inhibition of prostatic hyperplasia and tumor progression in mice and reduction of proliferation, survival and invasion of prostate cancer cells in vitro. Taken together, these findings implicate the use of resveratrol and its analogs as an attractive miRNA-mediated chemopreventive and therapeutic strategy in prostate cancer and the use of circulating miRNAs as potential predictive biomarkers for clinical development.

CircTRRAP (hsa_circ_0081234) participates in prostate cancer progression and glycolysis by HOXA1 via functioning as a miR-515-5p sponge

Dysregulated circular RNAs (circRNAs) are implicated in prostate cancer (PCa) progression. Hsa_circ_0081234 (circTRRAP) has been revealed as a facilitator in PCa, but the mechanisms associated with circTRRAP in PCa progression are largely unclear. The present study was to explore the regulatory mechanism of circTRRAP-mediated PCa progression. A total of 50 PCa tissues and normal tissues were collected. RNA levels of circTRRAP, microRNA (miR)-515-5p and homeobox A1 (HOXA1) were detected by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell viability, proliferation, migration, and invasion were estimated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide, 5-ethynyl-2ʹ-deoxyuridine (EdU) and transwell assays, respectively. Cell glycolysis was assessed by measuring glucose uptake and lactate production. The target interaction between circTRRAP or HOXA1 and miR-515-5p was investigated by the dual-luciferase reporter assay. We observed the overt upregulaiton of circTRRAP in PCa samples and cells. Silencing of circTRRAP lowered tumor growth in vivo and restrained PCa cell viability, proliferation, migration, invasion, and glycolysis in vitro. miR-515-5p was negatively regulated by circTRRAP and its deficiency reversed the inhibiting effects of circTRRAP knockdown on PCa cell malignancy and glycolysis. HOXA1 was confirmed as a miR-515-5p target and miR-515-5p overexpression lessened PCa cell malignancy and glycolysis by decreasing HOXA1 expression. Importantly, circTRRAP mediated HOXA1 expression by functioning as a miR-515-5p sponge. In conclusion, circTRRAP took part in PCa progression and glycolysis through mediating the miR-515-5p/HOXA1 axis, suggesting that circTRRAP can serve as a potential therapeutic target for PCa patients.

Cancer associated fibroblasts secreted exosomal miR-1290 contributes to prostate cancer cell growth and metastasis via targeting GSK3β

Cancer-associated fibroblasts (CAFs) play crucial roles in mediating tumor growth and metastasis via transferring exosomes to neighboring cells, whereas the mechanisms by which CAFs regulate the tumorgenesis of prostate cancer (PC) remain largely unknown. In this study, CAFs and normal fibroblasts (NFs) were isolated from PC tissues and adjacent normal tissues, respectively. Exosomes (NFs-Exo and CAFs-Exo) were then isolated from the supernatant of NFs and CAFs. Next, the differentially expressed miRNAs (DEMs) between NFs-Exo and CAFs-Exo were identified using RNA-sequencing. Cell viability, migration and invasion were detected with CCK-8 and Transwell assays. Protein expression was measured with western blot. We found that CAFs-Exo remarkably enhanced PC cell migration, invasion, stemness, epithelial-mesenchymal transition (EMT) and metastasis. Significantly, miR-1290 level was upregulated in CAFs-Exo compared to NFs-Exo. In addition, CAFs could transfer exosomes to PC cells, resulting in a marked increase of miR-1290 level in cells. Moreover, exosomal miR-1290 could inhibit GSK3β/β-catenin signaling by binding with the downstream target GSK3β mRNA. Meanwhile, miR-1290 antagomir notably reversed the effects of CAFs-Exo on PC cells through activating GSK3β/β-catenin signaling. Collectively, exosomal miR-1290 from CAFs could promote PC cell growth and metastasis via inhibiting GSK3β/β-catenin signaling, suggesting that miR-1290 may serve as potential therapeutic target for the treatment of PC.

RILP inhibits proliferation, migration, and invasion of PC3 prostate cancer cells

RILP (Rab-interacting lysosomal protein) is a key regulator of lysosomal transport and a potential tumor suppressor. However, the role of RILP in prostate cancer and the underlying mechanism of RILP in regulating the proliferation, migration, and invasion of prostate cancer cells remain to be studied. In this study, we confirmed RalGDS (Ral guanine nucleotide dissociation stimulator) as the interaction partner of RILP in PC3 prostate cancer cells. Immunofluorescence microscopy showed that RILP recruits RalGDS to the lysosomal compartment. We found that RILP inhibits the activation of RalA and downstream effector RalBP1, and negatively regulates the downstream molecular phosphorylation of Ras. We showed that RILP inhibits the proliferation, migration, and invasion of PC3 prostate cancer cells, which may give rise to novel ideas for cancer treatment.

Echinacoside decreases cell proliferation and inhibits cell invasion in PC3 androgen-independent prostate cancer cells

Purpose: The aim of this study was to determine the effects of Echinacoside on cell proliferation, invasion and mRNA expression changes of invasion-related genes in PC3 androgen-independent prostate cancer cells.
 Material Methods: The effect of Echinacoside on cell proliferation in PC3 cells was determined by XTT method. Anti-invasive efficacy was achieved using the transwell chamber. Total RNA isolation was performed by Trizol and cDNA was subsequently synthesized. mRNA expression changes of MMP2,MMP9, TIMP1, TIMP2 and TIMP3 were also performed in RT-PCR with SYBER Green.
 Results: In this study, the IC50 dose of Echinacoside in PC3 cells was determined as 55.21 μM at 48th hour. It was determined that echinacoside inhibited cell invasion in PC3 cells and reduced the invasion by 66% in the dose group. In addition, it was found statistically significant that Echinacoside increased TIMP 1 mRNA expression 1.96 times, TIMP2 mRNA expression 2.60 times, while decreasing MMP2 expression 3.82 times and MMP9 mRNA expression 1.54 times.
 Conclusion: In conclusion, it was revealed that echinacoside has an anti-proliferative effect on PC3 prostate cancer cells. It has also been shown that invasion-related genes can suppress invasion by regulating expression changes. With this study, preliminary data were presented in terms of detailed molecular biological studies to be carried out on echinacoside and its effect on prostate cancer.

Exosomal circKDM4A Induces CUL4B to Promote Prostate Cancer Cell Malignancy in a miR-338-3p-Dependent Manner.

Circular RNA lysine demethylase 4A (circKDM4A) is also named circ_0012098 and its abnormal expression has been confirmed in serum exosomes of prostate cancer (PC) patients. However, whether PC progression involves the exosomal circ_0012098 remains unknown. RNA expression of circKDM4A, microRNA-338-3p (miR-338-3p) and cullin 4B (CUL4B) was detected by quantitative real-time polymerase chain reaction. Protein expression was checked by Western blot. The positive expression rate of nuclear proliferation marker (ki-67) was analyzed by immunohistochemistry assay. Dual-luciferase reporter assay and RNA immunoprecipitation assay were used to identify the interaction between miR-338-3p and circKDM4A or CUL4B. Mouse model assay was performed to determine the effect of exosomal circKDM4A on tumorigenesis in vivo. CircKDM4A expression was significantly upregulated in the serum exosomes from PC patients compared with the exosomes from healthy volunteers. Exosomes treatment promoted the proliferation, migration and invasion of PC cells but inhibited apoptosis; however, these effects were attenuated after circKDM4A knockdown. Meanwhile, circKDM4A depletion restored exosome-increased circKDM4A expression. Additionally, circKDM4A acted as a miR-338-3p sponge, and miR-338-3p bound to CUL4B in PC cells. CircKDM4A regulated the effect of exosome-induced PC cell malignancy by interacting with miR-338-3p and CUL4B. Moreover, circKDM4A silencing relieved exosome-induced tumor growth in vivo. Exosomal circKDM4A promoted PC malignant progression by the miR-338-3p/CUL4B axis, providing a therapeutic target for PC.

FOXA1 inhibits hypoxia programs through transcriptional repression of HIF1A.

Intratumoral hypoxia is associated with castration-resistant prostate cancer (CRPC), a lethal disease. FOXA1 is an epithelial transcription factor that is down-regulated in CRPC. We have previously reported that FOXA1 loss induces epithelial-mesenchymal transition (EMT) and cell motility through elevated TGFβ signaling. However, whether FOXA1 directly regulates hypoxia pathways of CRPC tumors has not been previously studied. Here we report that FOXA1 down-regulation induces hypoxia transcriptional programs, and FOXA1 level is negatively correlated with hypoxia markers in clinical prostate cancer (PCa) samples. Mechanistically, FOXA1 directly binds to an intragenic enhancer of HIF1A to inhibit its expression, and HIF1A, in turn, is critical in mediating FOXA1 loss-induced hypoxia gene expression. Further, we identify CCL2, a chemokine ligand that modulates tumor microenvironment and promotes cancer progression, as a crucial target of the FOXA1-HIF1A axis. We found that FOXA1 loss leads to immunosuppressive macrophage infiltration and increased cell invasion, dependent on HIF1A expression. Critically, therapeutic targeting of HIF1A-CCL2 using pharmacological inhibitors abolishes FOXA1 loss-induced macrophage infiltration and PCa cell invasion. In summary, our study reveals an essential role of FOXA1 in controlling the hypoxic tumor microenvironment and establishes the HIF1A-CCL2 axis as one mechanism of FOXA1 loss-induced CRPC progression.

MAFG-AS1 is a prognostic biomarker and facilitates prostate cancer progression.

Long Noncoding RNAs (LncRNAs) have recently been identified as key regulator in tumor progression. The LncRNA MAFG-AS1 has been reported to facilitate the progression of multiple cancers, however, its role in prostate cancer is still unknown. Here, we reported that MAFG-AS1 was upregulated in prostate cancer. Importantly, high expression of MAFG-AS1 indicated advanced stage prostate cancer. Univariate and Multivariate Cox regression analyses showed that high MAFG-AS1 expression was independently correlated with poor progression-free interval (PFI). According to the result of The Cancer Genome Atlas (TCGA) database and tissue microarray, high MAFG-AS1 expression indicated a poor prognosis in prostate cancer patients. In addition, gene functional enrichment analysis revealed that MAFG-AS1 may be involved in ribosome biogenesis, ribonucleoprotein complex subunit organization, ribonucleoprotein complex assembly, rRNA metabolic process, structural constituent of ribosome, and ribonucleoprotein complex binding. Furthermore, MAFG-AS1 knockdown by siRNA markedly impaired prostate cancer cell proliferation, migration, and invasion.

Exosomes derived from myeloid-derived suppressor cells facilitate castration-resistant prostate cancer progression via S100A9/circMID1/miR-506-3p/MID1

BackgroundCastration-resistant prostate cancer (CRPC) is a major cause of recurrence and mortality among prostate cancer (PCa) patients. Myeloid-derived suppressor cells (MDSCs) regulate castration resistance in PCa. Previously, it was shown that intercellular communication was efficiently mediated by exosomes (Exos), but the role and the mechanism of MDSC-derived Exos in CRPC progression was unclear.MethodsIn this study, the circRNA expression profiles in PC3 cells treated with MDSC-Exo and control cells were investigated using a circRNA microarray.ResultsThe data showed that circMID1 (hsa_circ_0007718) expression was elevated in PC3 cells treated with MDSC-Exo. Moreover, high circMID1 expression was found in PCa compared with benign prostatic hyperplasia (BPH) tissues and in CRPC patients compared with hormone sensitive prostate cancer (HSPC) patients. Further studies showed that MDSC-Exo accelerated PCa cell proliferation, migration, and invasion, while circMID1 deficiency inhibited MDSC-Exo-regulated CRPC progression in vitro and in vivo. Mechanistically, MDSC-derived exosomal S100A9 increased circMID1 expression to sponge miR-506-3p, leading to increased MID1 expression and accelerated tumor progression.ConclusionTogether, our results showed that a S100A9/circMID1/miR-506-3p/MID1 axis existed in MDSC-Exo-regulated CRPC progression, which provided novel insights into MDSC-Exo regulatory mechanisms in CRPC progression.

Identification of target and pathway of aspirin combined with Lipitor treatment in prostate cancer through integrated bioinformatics analysis

PurposeOur previous studies have confirmed that aspirin combined with Lipitor inhibited the development of prostate cancer (PCa), but the mechanisms need to be comprehensively expounded. The study aims to screen out the hub genes of combination therapy and to explore their association with the pathogenesis and prognosis of PCa. MethodsGene expressions were quantified by RNA sequencing (RNA-seq). Altered biological function, pathways of differentially expressed genes (DEGs), protein-protein interaction network, the filtering of hub genes, gene co-expression and the pathogenesis and prognosis were revealed by bioinformatics analysis. The correlation between hub gene expression and patient survival was validated by Kaplan-Meier. The effects of silent DNA replication and sister chromatid cohesion 1 (siDSCC1) combined with Lipitor and aspirin on DSCC1 expression, viability, invasion and migration of PCa cells were detected by qRT-PCR, Wound healing and transwell assays. Results157 overlapped DEGs involved in FoxO, PI3K-Akt and p53 signaling pathways were identified. Ten hub genes (NEIL3, CDC7, DSCC1, CDC25C, PRIM1, MCM10, FBXO5, DTL, SERPINE1, EXO1) were verified to be correlated with the pathology and prognosis of PCa. DSCC1 silencing not only inhibited the viability, migration and invasion of PCa cells, but also strengthened the suppressing effects of Lipitor and aspirin alone or in combination on PCa cells. ConclusionThe enrichment pathways and targets of Lipitor combined with aspirin in PCa are discovered, and DSCC1 silencing can potentiate the effect of Lipitor combined with aspirin in the treatment of PCa.

Verification of cell cycle-associated cyclin-dependent kinases facilitated prostate cancer progression by integrated bioinformatic analysis and experimental validation

IntroductionCell cycle-associated cyclin-dependent kinases (ccCDKs) are essential regulators known to control cell division and facilitate tumorigenesis and progression. However, there is currently no comprehensive study of distinct ccCDKs in prostate cancer (PCa). The purpose of this study was to determine the value of ccCDK expression in predicting the prognosis of patients with PCa and to identify the gene functions of ccCDK in PCa. MethodsThe UALCAN databases were analyzed to examine the expression of CDKs in prostate cancer. The Human Protein Atlas was used to verify the expression of CDKs online. Then, we assessed the prognostic values of CDKs using GEPIA. GeneMANIA and Metascape analyses were used to predict biological functions. We analyzed the mutation of CDKs by cBioPortal. The TIMER database was used to evaluate the correlation of CDKs and immune infiltration. The expression of CDKs in tissue was examined through quantitative real-time polymerase chain reaction. After that, we focused on CDK3 and identified the expression of CDK3 by immunohistochemistry and western blot. The functions of CDK3 in C4-2 cell proliferation were determined by CCK-8 assays. C4-2 cells were tested for their ability to invade and migrate through transwell and wound healing assays. ResultsThe results showed that CDK1/3/4/5/6/16 was expressed at relatively higher levels in PCa tissues than in normal tissues. Patients with low expression of CDK1/3/5/16 exhibited significantly better disease-free survival than those with high expression. ccCDKs were enriched in the IL-18 signaling pathway and correlated with the infiltration of immune cells in PCa. Moreover, our cohort study data verified that there were significantly higher expression of CDK1/3/5/16 in PCa tissues compared to benign prostate hyperplasia tissues, and CDK3 was remarkably associated with a shorter progression-free survival for biochemical recurrence in PCa patients. CDK3 was positively expressed in PCa cells and tissues, and functional experiments demonstrated that silencing CDK3 inhibited PCa cell proliferation, migration, and invasion. ConclusionsOur study provides new evidence of ccCDKS in promoting PCa progression and implies that CDK3 may serve as an oncogene in PCa and may be valuable in the prognosis of biochemical recurrence in PCa patients.

Curcumol Inhibits the Development of Prostate Cancer by miR-125a/STAT3 Axis

Aim This study aimed to learn the antineoplastic activity of curcumol (Cur) on prostate cancer (PCa) and elucidate its potential molecular mechanism. Methods The proliferation, invasion, and migration of PCa cells (PC3 and 22RV1) were detected by the cell counting kit 8 (CCK8), transwell, and wound healing assay, respectively. The expression of genes and proteins was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blotting (WB), respectively. The protein expression in tissues and cells was tested through immunohistochemistry (IHC) and immunocytochemistry (ICC). Enzyme-linked immunosorbent assay (ELISA) was utilized to quantify the level of epidermal growth factor (EGF) and vascular endothelial growth factor (VEGF). The interaction between microRNA125a (miR-125a) and the signal transducer and activator of transcription 3 (STAT3) was confirmed via dual-luciferase reporter assay. Results Cur effectively restrained the proliferation, invasion, and migration of PC3 and 22RV1 cells. After Cur intervention, miR-125a, miR-375, miR-149, miR-183, and miR-106b were all upregulated in PC3 cells, among which miR-125a was the most significantly upregulated. Dual-luciferase reporter assay combined with qRT-PCR and WB experiments confirmed that miR-125a targeted STAT3. Both in vitro and in vivo, Cur enhanced miR-125a expression and suppressed the activation of the STAT3 pathway in PCa. Also, Cur effectively inhibited the growth of PCa. Conclusion Cur inhibited the development of PCa by miR-125a/STAT3 axis. This may provide a potential agent for treating PCa.

ARPC1A is regulated by STAT3 to inhibit ferroptosis and promote prostate cancer progression.

The aim of this study was to investigate the biological function and molecular mechanism of ARPC1A (actin related protein 2/3 complex subunit 1A) in prostate cancer progression. RT-qPCR and IHC results showed that the level of ARPC1A in prostate cancer tissues was significantly higher than that in adjacent tissues. The results of TCGA (the cancer genome atlas) database analysis showed that high expression of ARPC1A indicates poor prognosis in prostate cancer patients. In vitro functional experiments confirmed that downregulation of ARPC1A expression resulted in decreased cell viability and invasive ability of prostate cancer cells, as ARPC1A knockdown promoted ferroptosis. The transcriptional regulation mechanism of STAT3 (signal transduction and activators of transcription 3) on ARPC1A was elucidated by Co-IP, ChIP and luciferase reporter assays. In vivo experiments also supported the in vitro results. We propose that reduced ARPC1A expression inhibits prostate cancer cell viability and invasion in a ferroptotic manner. The ARPC1A level may serve as an independent predictor of prognosis in prostate cancer patients.

Inhibition of circ_0081234 reduces prostate cancer tumor growth and metastasis via the miR-1/MAP 3K1 axis.

Circular RNAs (circRNAs) are crucial regulators of tumor occurrence and progression, and circRNAs are enriched and stable in exosomes. The present study aimed to explore the role and potential mechanism of cancer-derived exosomal circ_0081234 in prostate cancer (PCa). Exosomes were extracted using the ExoQuick Precipitation Kit (System Biosciences, Mountain View, CA, USA). The levels of circ_0081234, miR-1 and mitogen-activated protein kinase kinase kinase 1 (MAP 3K1) were examined using a quantitative real-time polymerase chain reaction or western blotting. Cell migration and invasion were evaluated via a transwell assay. The protein levels of N-cadherin, vimentin and E-cadherin were detected by western blotting. The interaction between miR-1 and circ_0081234 or MAP 3K1 was verified via a dual-luciferase reporter assay and an RNA pull-down assay. The circ_0081234 level was increased in PCa tissues with spinal metastasis in comparison to primary PCa tissues without spinal metastasis. Exosomal circ_0081234 promoted the migration, invasion and epithelial-mesenchymal transition of PCa cells. Knockdown of circ_0081234 blocked PCa cell progression by regulating miR-1. In addition, miR-1 overexpression suppressed PCa cell progression by repressing MAP 3K1. Moreover, circ_0081234 increased MAP 3K1 level via sponging miR-1. Depletion of circ_0081234 inhibited tumor growth in vivo. Exosomal circ_0081234 promoted migration, invasion and epithelial-mesenchymal transition of PCa cells by regulating the miR-1/MAP 3K1 axis.

PRDM16, negatively regulated by miR-372-3p, suppresses cell proliferation and invasion in prostate cancer.

Prostate cancer (PCa) is one of the most prevalent malignant tumours. The alternation of microRNAs (miRNAs) expression is associated with prostate cancer progression, whereas its way to influence progression of prostate cancer remains elusive. The expression levels of PRDM16 mRNA and miR-372-3p in PCa cell lines were analysed using qRT-PCR. The protein expression of PRDM16 in PCa cell lines was also analysed using Western blot. CCK-8, wound healing and Transwell assays were applied to examine cell proliferation, migration, and invasion in prostate cancer cells, respectively. Dual-luciferase reporter assay was utilised to validate the interaction between miR-372-3p and PRDM16. In the present study, markedly decreased PRDM16 mRNA and protein expression levels were observed in prostate cancer cells. PRDM16 overexpression hampered cellular proliferation, migration, and invasion, while silencing PRDM16 had the opposite effect. Moreover, miR-372-3p could target the regulation expression of PRDM16. Rescue experiments demonstrated that upregulating miR-372-3p conspicuously restored the inhibitory effect of increased PRDM16 on cell proliferation, migration, and invasion in PCa. Overall, our study clarifies the biological role of miR-372-3p/PRDM16 axis in prostate cancer progression, which may be effective biomarkers for clinical treatment of prostate cancer.

Cirsilineol Inhibits the Proliferation of Human Prostate Cancer Cells by Inducing Reactive Oxygen Species (ROS)-Mediated Apoptosis

Cirsilineol has been reported to exhibit anticancer effects against several human cancer cell lines. The present study was designed to evaluate the anticancer effects of cirsilineol against the human DU-145 prostate cancer cells. The results showed that cirsilineol suppressed the proliferation of DU-145 cancer cells in a dose-dependent manner with minimal cytotoxic effects against the normal cells. The IC50 of cirsilineol was found to be 7 μM and 110 μM against prostate cancer DU-145 and normal HPrEC prostate cells, respectively. Acridine orange and ethidium bromide (AO/EB) staining showed that cirsilineol induced apoptosis in DU-145 prostate cancer cells. The Annexin V/PI staining further confirmed the induction of apoptosis in DU-145 cells. The western blot analysis showed that cirsilineol suppressed the expression of Bax and upregulated the expression of Bcl-2 in prostate cancer DU-145 cells. Moreover, cirsilineol caused a dose-dependent increase in reactive oxygen species (ROS) levels in prostate cancer. Wound healing and Transwell assays showed that cirsilineol inhibits migration and invasion of DU-145 prostate cancer cells. Summing up, the results suggest that cirsilineol suppresses the proliferation of prostate cancer cells and may prove to be a beneficial lead molecule for the development of chemotherapy for prostate cancer.

The effects of endosulfan on cell migration and invasion in prostate cancer cells via the KCNQ1OT1/miR-137-3p/PTP4A3 axis

Endosulfan belongs to persistent organic pollutants (POPs), closely related to an increased risk of prostate cancer (PCa). The existing evidence shows that lncRNAs compete with miRNAs for binding sites and contribute to the onset and progression of human malignancies. In this study we investigate how endosulfan promotes cell migration and invasion in DU145 and PC3 prostate cancer cells through epigenetic mechanism of lncRNA-miRNA regulation. Based on our past research we focused on PTP4A3 and constructed wild-type (WT) and mutant PTP4A3 plasmids for further analysis. Our results revealed that transfection of PTP4A3-WT can lead to changes in the expression of epithelial-mesenchymal transition (EMT) biomarkers and critical proteins in the TGF-β signaling pathway, and promote cell migration and invasion in PCa cells. Bioinformatics analysis shows that there were complementary sequences in PTP4A3 3′-UTR and KCNQ1OT1 3′-UTR to the seed sequence of hsa-miR-137-3p, and dual luciferase reporter assay indicates the potential binding capacity of miR-137-3p to 3′-UTR of PTP4A3 and KCNQ1OT1. We found that miR-137-3p mimic inhibited cell migration and invasion, as well as repressed alterations of EMT biomarkers and critical proteins in the TGF-β signaling pathway. Rescue experiment results revealed that co-transfection of miR-137-3p mimic and PTP4A3-WT plasmid reversed these changes following transfection with miR-137-3p mimic alone. We found that KCNQ1OT1 was predominantly distributed in the cytoplasm from a subcellular fractionation assay. Functionally, silencing of KCNQ1OT1 repressed cell migration and invasion, and caused alterations of EMT biomarkers and critical proteins in the TGF-β signaling pathway, which were all restored by co-transfection with anti-miR-137-3p or PTP4A3-WT plasmid. Furthermore, overexpression of miR-137-3p or silencing of KCNQ1OT1 dramatically rescued the effects of endosulfan on promoting cell migration and invasion. These findings suggest that endosulfan can indeed promote cell migration and invasion via the KCNQ1OT1/miR-137-3p/PTP4A3 axis in PCa cells.