β-Arrestin2 Contributes to Cell Viability and Proliferation via the Down-Regulation of FOXO1 in Castration-Resistant Prostate Cancer

Insight into the regulatory mechanism of β-arrestin2 and its emerging role in diseases

β-arrestin2, a member of the arrestin family, mediates the desensitization and internalization of most G protein-coupled receptors (GPCRs) and functions as a scaffold protein in signalling pathways. Previous studies have demonstrated that β-arrestin2 expression is dysregulated in malignant tumours, fibrotic diseases, cardiovascular diseases and metabolic diseases, suggesting its pathological roles. Transcription and post-transcriptional modifications can affect the expression of β-arrestin2. Furthermore, post-translational modifications, such as phosphorylation, ubiquitination, SUMOylation and S-nitrosylation affect the cellular localization of β-arrestin2 and its interaction with downstream signalling molecules, which further regulate the activity of β-arrestin2. This review summarizes the structure and function of β-arrestin2 and reveals the mechanisms involved in the regulation of β-arrestin2 at multiple levels. Additionally, recent studies on the role of β-arrestin2 in some major diseases and its therapeutic prospects have been discussed to provide a reference for the development of drugs targeting β-arrestin2.

Molecular landscape for risk prediction and personalized therapeutics of castration-resistant prostate cancer: at a glance

Prostate cancer (PCa) is commonly occurred with high incidence in men worldwide, and many patients will be eventually suffered from the dilemma of castration-resistance with the time of disease progression. Castration-resistant PCa (CRPC) is an advanced subtype of PCa with heterogeneous carcinogenesis, resulting in poor prognosis and difficulties in therapy. Currently, disorders in androgen receptor (AR)-related signaling are widely acknowledged as the leading cause of CRPC development, and some non-AR-based strategies are also proposed for CRPC clinical analyses. The initiation of CRPC is a consequence of abnormal interaction and regulation among molecules and pathways at multi-biological levels. In this study, CRPC-associated genes, RNAs, proteins, and metabolites were manually collected and integrated by a comprehensive literature review, and they were functionally classified and compared based on the role during CRPC evolution, i.e., drivers, suppressors, and biomarkers, etc. Finally, translational perspectives for data-driven and artificial intelligence-powered CRPC systems biology analysis were discussed to highlight the significance of novel molecule-based approaches for CRPC precision medicine and holistic healthcare.

mRNA Levels of Aromatase, 5α-Reductase Isozymes, and Prostate Cancer-Related Genes in Plucked Hair from Young Men with Androgenic Alopecia

Androgenic alopecia (AGA) is the most prevalent type of progressive hair loss and has psychological repercussions. Nevertheless, the effectiveness of current pharmacological treatments remains limited, in part because the molecular basis of the disease has not been fully elucidated. Our group previously highlighted the important roles of aromatase and 5α-reductase (5α-R) in alopecia in young women with female pattern hair loss. Additionally, an association has been proposed between AGA and prostate cancer (PCa), suggesting that genes implicated in PCa would also be involved in AGA. A low-invasive, sensitive, and precise method was used to determine mRNA levels of aromatase, 5α-R isozymes, and 84 PCa-related genes in samples of plucked hair from young men with AGA and controls. Samples were obtained with a trichogram from the vertex scalp, and mRNA levels were quantified using real-time RT-PCR. The men with AGA had significantly higher 5α-R2 mRNA levels in comparison to controls; interestingly, some of them also showed markedly elevated mRNA levels of 5α-R1 or 5α-R3 or of both, which may explain the varied response to 5α-R inhibitor treatments. The men with AGA also showed significant changes versus controls in 6 out of the 84 genes implicated in PCa. This study contributes greater knowledge of the molecular bases of AGA, facilitating early selection of the most appropriate pharmacological therapy and opening the way to novel treatments.

β-Arrestin2 promotes docetaxel resistance of castration-resistant prostate cancer via promoting hnRNP A1-mediated PKM2 alternative splicing

PURPOSE

To investigate the influence of β-arrestin2 on the docetaxel resistance in castration-resistant prostate cancer (CRPC) and elucidate the underlying molecular mechanisms.

METHODS

PC3 and DU145 cells with stable β-arrestin2 overexpression and C4-2 cells with stable β-arrestin2 knockdown, were constructed via using lentivirus and puromycin selection. MTT and colony formation assays were carried out to investigate the effect of β-arrestin2 expression on the docetaxel resistance of CRPC cells. Glycolysis analysis was used to assess the glycolytic capacity modulated by β-arrestin2. GO enrichment analysis, gene set enrichment analysis and Spearman correlation test were carried out to explore the potential biological function and mechanism via using public data from GEO and TCGA. The expressions of PKM2, Phospho-PKM2, Phospho-ERK1/2 and hnRNP A1 were detected by western blot. Functional blocking experiments were carried out to confirm the roles of PKM2 and hnRNP A1 in the regulation of β-arrestin2's biological functions via silencing PKM2 or hnRNP A1 expression in cells with stable β-arrestin2 overexpression. Finally, nude mice xenograft models were established to confirm the experimental results of cell experiments.

RESULTS

β-Arrestin2 significantly decreased the sensitivity of CRPC cells to docetaxel stimulation, through enhancing the phosphorylation and expression of PKM2. Additionally, β-arrestin2 increased PKM2 phosphorylation via the ERK1/2 signaling pathway and induced PKM2 expression in a post-transcriptional manner through an hnRNP A1-dependent PKM alternative splicing mechanism, rather than by inhibiting its ubiquitination degradation.

CONCLUSION

Our findings indicate that the β-arrestin2/hnRNP A1/PKM2 pathway could be a promising target for treating docetaxel-resistant CRPC.

β-arrestin 2 and Epac2 cooperatively mediate DRD1-stimulated proliferation of human neural stem cells and growth of human cerebral organoids

G protein coupled receptors (GPCRs) reportedly relay specific signals, such as dopamine and serotonin, to regulate neurogenic processes though the underlying signaling pathways are not fully elucidated. Based on our previous work which demonstrated Dopamine receptor D1 (DRD1) effectively induces the proliferation of human neural stem cells, here we continued to show the knockout of β-arrestin 2 by CRISPR/Cas9 technology significantly weakened the DRD1-induced proliferation and neurosphere growth. Furthermore, inhibition of the downstream p38 MAPK by its specific inhibitors or small hairpin RNA mimicked the weakening effect of β-arrestin 2 knockout. In addition, blocking of Epac2, a PKA independent signal pathway, by its specific inhibitors or small hairpin RNA also significantly reduced DRD1-induced effects. Simultaneous inhibition of β-arrestin 2/p38 MAPK and Epac2 pathways nearly abolished the DRD1-stimulated neurogenesis, indicating the cooperative contribution of both pathways. Consistently, the expansion and folding of human cerebral organoids as stimulated by DRD1 were also mediated cooperatively by both β-arrestin 2/p38 MAPK and Epac2 pathways. Taken together, our results reveal that GPCRs apply at least two different signal pathways to regulate neurogenic processes in a delicate and balanced manners.

An Insight into GPCR and G-Proteins as Cancer Drivers

G-protein-coupled receptors (GPCRs) are the largest family of cell surface signaling receptors known to play a crucial role in various physiological functions, including tumor growth and metastasis. Various molecules such as hormones, lipids, peptides, and neurotransmitters activate GPCRs that enable the coupling of these receptors to highly specialized transducer proteins, called G-proteins, and initiate multiple signaling pathways. Integration of these intricate networks of signaling cascades leads to numerous biochemical responses involved in diverse pathophysiological activities, including cancer development. While several studies indicate the role of GPCRs in controlling various aspects of cancer progression such as tumor growth, invasion, migration, survival, and metastasis through its aberrant overexpression, mutations, or increased release of agonists, the explicit mechanisms of the involvement of GPCRs in cancer progression is still puzzling. This review provides an insight into the various responses mediated by GPCRs in the development of cancers, the molecular mechanisms involved and the novel pharmacological approaches currently preferred for the treatment of cancer. Thus, these findings extend the knowledge of GPCRs in cancer cells and help in the identification of therapeutics for cancer patients.

The Adipokine Component in the Molecular Regulation of Cancer Cell Survival, Proliferation and Metastasis

A hormonal imbalance may disrupt the rigorously monitored cellular microenvironment by hampering the natural homeostatic mechanisms. The most common example of such hormonal glitch could be seen in obesity where the uprise in adipokine levels is in virtue of the expanding bulk of adipose tissue. Such aberrant endocrine signaling disrupts the regulation of cellular fate, rendering the cells to live in a tumor supportive microenvironment. Previously, it was believed that the adipokines support cancer proliferation and metastasis with no direct involvement in neoplastic transformations and tumorigenesis. However, the recent studies have reported discrete mechanisms that establish the direct involvement of adipokine signaling in tumorigenesis. Moreover, the individual adipokine profile of the patients has never been considered in the prognosis and staging of the disease. Hence, the present manuscript has focused on the reported extensive mechanisms that culminate the basis of poor prognosis and diminished survival rate in obese cancer patients.

circEVI5 acts as a miR-4793-3p sponge to suppress the proliferation of gastric cancer

Circular RNAs (circRNAs) are a novel class of endogenous noncoding RNAs (ncRNAs) with a covalently closed loop structure. Accumulating evidence shows that circRNAs play vital roles in the growth, metastasis, treatment and prognosis of various cancers. However, the detailed functions and underlying mechanisms of circEVI5 (hsa_circ_0013162) in gastric cancer (GC) remain undocumented. In this study, the expression levels and prognostic value of circEVI5 were validated in GC tissue samples by using qRT-PCR. circEVI5 was significantly downregulated in GC tissues and cells, and low circEVI5 expression was correlated with poor prognosis. Next, in vitro CCK-8 assay, EdU incorporation assay, PI staining cell cycle assay, and in vivo xenograft mouse models were conducted to assess the functions of circEVI5. Gain of function experiments indicated that circEVI5 could inhibit GC cell proliferation and retard the cell cycle. Moreover, bioinformatics prediction showed that circEVI5 binds to miR-4793-3p, while FOXO1 may be a target of miR-4793-3p. Pull-down assays, RNA immunoprecipitation (RIP) assays, luciferase assays, and western blot were used to confirm the interactions between circEVI5, miR-4793-3p, and FOXO1. Functional assays demonstrated that circEVI5 suppressed the proliferation of GC by sponging miR-4793-3p and increasing FOXO1 expression levels. In conclusion, our study demonstrated that circEVI5 can bind miR-4793-3p as a ceRNA to eliminate the negative regulation of FOXO1, therefore suppressing GC proliferation.

Long non‑coding RNA ZFPM2‑AS1 promotes colorectal cancer progression by sponging miR‑137 to regulate TRIM24

Accumulating evidence indicates that long non‑coding RNAs (lncRNAs) may serve essential roles during tumorigenesis of colorectal cancer (CRC). The lncRNA ZFPM2‑AS1 was observed to be involved in the progression of numerous types of cancer, such as lung adenocarcinoma and cervical cancer. The aim of the present study was to investigate the expression levels and function of ZFPM2‑AS1 in CRC. Expression levels of ZFPM2‑AS1 in tissue and CRC cells were measured by reverse transcription‑quantitative PCR. Furthermore, cell proliferation and Transwell assays were conducted to investigate the functional role of ZFPM2‑AS1 in vitro. In addition, bioinformatics analysis, luciferase reporter assay, RNA immunoprecipitation assay and western blotting were performed to explore the possible underlying mechanism. The expression levels of ZFPM2‑AS1 were significantly upregulated in tissue samples from patients with CRC and CRC cell lines compared with normal tissue and normal human colorectal mucosa cell line. Notably, the upregulation of ZFPM2‑AS1 was significantly associated with tumor size, histological differentiation, lymph node metastasis and TNM stage. In addition, ZFPM2‑AS1 knockdown significantly inhibited cell proliferation, migration and invasion compared with the control group in vitro. Moreover, it was found that ZFPM2‑AS1 positively regulated tripartite motif containing 24 (TRIM24) expression by sponging miR‑137. In conclusion, the present study indicated that ZFPM2‑AS1 may serve as an oncogene in CRC by regulating the miR‑137/TRIM24 axis.

SPTLC1 inhibits cell growth via modulating Akt/FOXO1 pathway in renal cell carcinoma cells

Serine palmitoyltransferase long chain-1 (SPTLC1), which is the rate-limiting enzyme for sphingolipid biosynthesis, has been indicated to be essential for carcinoma cell survival and proliferation in recent, but its role in the regulation of renal cell carcinoma (RCC) remains unknown. In the present study, we found that SPTLC1 expression was significantly decreased in RCC tissues compared to non-tumor tissues, and low SPTLC1 expression was associated with poor overall survival of RCC patients. In addition, our results revealed that forced expression of SPTLC1 could significantly inhibit cell growth in vitro and in vivo via, at least in part, modulating Akt/FOXO1 signaling pathway, thus representing a novel role of SPTLC1 in the regulation of tumor growth in RCC for the first time.

New Routes in GPCR/β-Arrestin-Driven Signaling in Cancer Progression and Metastasis

Tumor cells acquire invasive and metastatic behavior by sensing changes in the localization and activation of signaling pathways, which in turn determine changes in actin cytoskeleton. The core-scaffold machinery associated to β-arrestin (β-arr) is a key mechanism of G-protein coupled receptors (GPCR) to achieve spatiotemporal specificity of different signaling complexes driving cancer progression. Within different cellular contexts, the scaffold proteins β-arr1 or β-arr2 may now be considered organizers of protein interaction networks involved in tumor development and metastatic dissemination. Studies have uncovered the importance of the β-arr engagement with a growing number of receptors, signaling molecules, cytoskeleton regulators, epigenetic modifiers, and transcription factors in GPCR-driven tumor promoting pathways. In many of these molecular complexes, β-arrs might provide a physical link to active dynamic cytoskeleton, permitting cancer cells to adapt and modify the tumor microenvironment to promote the metastatic spread. Given the complexity and the multidirectional β-arr-driven signaling in cancer cells, therapeutic targeting of specific GPCR/β-arr molecular mechanisms is an important avenue to explore when considering future new therapeutic options. The focus of this review is to integrate the most recent developments and exciting findings of how highly connected components of β-arr-guided molecular connections to other pathways allow precise control over multiple signaling pathways in tumor progression, revealing ways of therapeutically targeting the convergent signals in patients.

Identification of the key genes and pathways in prostate cancer

Prostate cancer (PCa) is one of the most common malignancies in men globally. The aim of the present study was to identify the key genes and pathways involved in the occurrence of PCa. Gene expression profile (GSE55945) was downloaded from Gene Expression Omnibus, and the differentially expressed genes (DEGs) were identified. Subsequently, Gene ontology analysis, KEGG pathway analysis and protein-protein interaction (PPI) analysis of DEGs were performed. Finally, the identified key genes were confirmed by immunohistochemistry. The GO analysis results showed that the DEGs were mainly participated in cell cycle, cell division, cell development and cell junction. The KEGG pathway analysis showed that the DEGs were mainly enriched in proteoglycans in cancer, endocytosis, focal adhesion and hippo signaling pathway. The PPI analysis results showed that RPS21, FOXO1, BIRC5, POLR2H, RPL22L1 and NPM1 were the key genes involved in the occurrence of PCa, and the Module analysis indicated that the occurrence of PCa was associated with cell cycle, oocyte meiosis and ribosome biogenesis. IHC result showed that the expression of RPS21, BIRC5, POLR2H, RPL22L1 and NPM1 were significantly upregulated in PCa, while the expression of FOXO1 was significantly downregulated in PCa, matching with the bioinformatics analysis. Taken together, several key genes and pathways were identified involved in PCa, which might provide the potential biomarker for prognosis, diagnosis and drug targets.

β-arrestin1-medieated inhibition of FOXO3a contributes to prostate cancer cell growth in vitro and in vivo

Recently, β-arrestin1 has been indicated as a prostate cancer promoter through promoting cell proliferation and epithelial to mesenchymal transition, but its underlying mechanism remains unclear. Here, our data revealed that β-arrestin1 could promote cell growth through inhibiting the transcriptional activity and expression of FOXO3a in prostate cancer cells in vitro and in vivo. We found that β-arrestin1 could promote the cell and tumor growth of prostate cancer, and β-arrestin1 expression represented a negative correlation with FOXO3a expression but not FOXO1 expression in prostate cancer cell lines and tissues. In addition, forced expression of β-arrestin1 induced a significant decrease of FOXO3a expression but had no clear effect on FOXO1 expression. Mechanistically, β-arrestin1 could interact with FOXO3a and MDM2, respectively, and promote the interaction between FOXO3a and MDM2, whereas it had no obvious interaction with FOXO1. Furthermore, β-arrestin1 could inhibit the transcriptional activity of FOXO3a via Akt and ERK1/2 pathways. Together, our results revealed a novel mechanism for β-arrestin1 in the regulation of the prostate cancer procession through inhibiting FOXO3a.

Platelet-targeted pharmacologic treatments as anti-cancer therapy

Platelets act as multifunctional cells participating in immune response, inflammation, allergy, tissue regeneration, and lymphoangiogenesis. Among the best-established aspects of a role of platelets in non-hemostatic or thrombotic disorders, there is their participation in cancer invasion and metastasis. The interaction of many different cancer cells with platelets leads to platelet activation, and on the other hand platelet activation is strongly instrumental to the pro-carcinogenic and pro-metastatic activities of platelets. It is thus obvious that over the last years a lot of interest has focused on the possible chemopreventive effect of platelet-targeted pharmacologic treatments. This article gives an overview of the platelet-targeted pharmacologic approaches that have been attempted in the prevention of cancer development, progression, and metastasis, including the application of anti-platelet drugs currently used for cardiovascular disease and of new and novel pharmacologic strategies. Despite the fact that very promising results have been obtained with some of these approaches in pre-clinical models, with the exclusion of aspirin, clinical evidence of a beneficial effect of anti-platelet agents in cancer is however still largely missing. Future studies with platelet-targeted drugs in cancer must carefully deal with design issues, and in particular with the careful selection of patients, and/or explore novel platelet targets in order to provide a solution to the critical issue of the risk/benefit profile of long-term anti-platelet therapy in the prevention of cancer progression and dissemination.

Beta-Arrestin 1 Mediates Liver Thyrotropin Regulation of Cholesterol Conversion Metabolism via the Akt-Dependent Pathway

After activation, G protein-coupled receptors (GPCRs) are desensitized by β-arrestins (ARRBs). Moreover, ARRBs can initiate a second wave of signaling independent of G proteins. Thyroid-stimulating hormone receptor (TSHR) is one of the GPCR members. In our previous study, TSHR was identified in the liver; the major role of TSHR in cholesterol metabolism was illustrated, as TSH could regulate hepatic cholesterol metabolism via cAMP/PKA/CREB/HMGCR and SREBP2/HNF4α/CYP7A1 pathways. It has been reported that ARRB2 predominates over ARRB1 in TSHR internalization. However, the significance of ARRBs in TSH-initiated cholesterol metabolism has not been illustrated. In our study, the effects of ARRBs on TSH-regulated cholesterol metabolism are investigated. ARRB1/2 was genetically inactivated in C57BL/6 mice and HepG2 cell line, respectively. Cholesterol levels in arrestin-knockout mice and arrestin-knockdown cells were measured. Molecules participating in cholesterol metabolism were analyzed. It turned out that deficiencies in ARRB1 led to decreased cholesterol levels and decreased TSH-stimulated AKT phosphorylation. Subsequently, the inhibitory effect on CYP7A1 by SREBP2 was reduced due to lowered mature SREBP2 level. Other than the failures of TSH in ARRB-knockdown cells, the AKT activator SC79 could enhance AKT phosphorylation and mature SREBP2 level. Our results demonstrate that ARRBs, especially ARRB1, are involved in TSH-regulated cholesterol metabolism through the AKT pathway.

β-Arrestin2 mediates progression of murine primary myelofibrosis

Primary myelofibrosis is a myeloproliferative neoplasm associated with significant morbidity and mortality, for which effective therapies are lacking. β-Arrestins are multifunctional adaptor proteins involved in developmental signaling pathways. One isoform, β-arrestin2 (βarr2), has been implicated in initiation and progression of chronic myeloid leukemia, another myeloproliferative neoplasm closely related to primary myelofibrosis. Accordingly, we investigated the relationship between βarr2 and primary myelofibrosis. In a murine model of MPLW515L-mutant primary myelofibrosis, mice transplanted with donor βarr2-knockout (βarr2-/-) hematopoietic stem cells infected with MPL-mutant retrovirus did not develop myelofibrosis, whereas controls uniformly succumbed to disease. Although transplanted βarr2-/- cells homed properly to marrow, they did not repopulate long-term due to increased apoptosis and decreased self-renewal of βarr2-/- cells. In order to assess the effect of acute loss of βarr2 in established primary myelofibrosis in vivo, we utilized a tamoxifen-induced Cre-conditional βarr2-knockout mouse. Mice that received Cre (+) donor cells and developed myelofibrosis had significantly improved survival compared with controls. These data indicate that lack of antiapoptotic βarr2 mediates marrow failure of murine hematopoietic stem cells overexpressing MPLW515L. They also indicate that βarr2 is necessary for progression of primary myelofibrosis, suggesting that it may serve as a novel therapeutic target in this disease.

Dissecting the roles of the androgen receptor in prostate cancer from molecular perspectives

Androgen receptor plays a pivotal role in prostate cancer progression, and androgen deprivation therapy to intercept androgen receptor signal pathway is an indispensable treatment for most advanced prostate cancer patients to delay cancer progression. However, the emerging of castration-resistant prostate cancer reminds us the alteration of androgen receptor, which includes androgen receptor mutation, the formation of androgen receptor variants, and androgen receptor distribution in cancer cells. In this review, we introduce the process of androgen receptor and also its variants' formation, translocation, and function alteration by protein modification or interaction with other pathways. We dissect the roles of androgen receptor in prostate cancer from molecular perspective to provide clues for battling prostate cancer, especially castration-resistant prostate cancer.

β-arrestin1 at the cross-road of endothelin-1 signaling in cancer

The advent of targeted therapeutics in human cancer has begun to find novel druggable targets and, in this context, the endothelin-1 receptor (ET-1R), namely ET_A receptor (ET_AR) and ET_B receptor, among the GPCR family represents a class of highly druggable molecules in cancer. ET-1R are aberrantly expressed in human malignancies, potentially representing prognostic factors. Their activation by ligand stimulation initiate signaling cascades activating different downstream effectors, allowing precise control over multiple signaling pathways. ET-1R regulates cell proliferation, survival, motility, cytoskeletal changes, angiogenesis, metastasis as well as drug resistance. The molecular events underlying these responses are the activation of transcriptional factors and coactivators, and downstream genes, acting as key players in tumor growth and progression. ET-1R represent crucial cancer targets that have been exploited for ET-1R therapeutics. Importantly, efforts to explore new information of ET_AR in cancer have uncovered that their functions are crucially regulated by multifunctional scaffold protein β-arrestins (β-arrs) which orchestrate the multidimensionality of ET_AR signaling into highly regulated and distinct signaling complexes, a property that is highly advantageous for tumor signaling. Moreover, the role of β-arr1 in ET-1 signaling in cancer highlights why the pleiotropic effects of ET-1 and its dynamic signaling are more complex than previously recognized. In order to improve therapeutic strategies that interfere with the widespread effects of ET-1R, it is important to consider antagonists able to turn the receptors “off” selectively controlling β-arr1-dependent signaling, highlighting the possibility that targeting ET_AR/β-arr1 may display a large therapeutic window in cancer.

Knockdown of PSCA induces EMT and decreases metastatic potentials of the human prostate cancer DU145 cells

Background

Prostate stem cell antigen (PSCA) expression has been shown to correlate with prostatic carcinogenesis and prostate cancer (PCa) progression. The underlying mechanisms for these processes are currently unknown. Epithelial to mesenchymal transition (EMT) has been associated with the invasiveness and the distant metastasis of PCa. In this study, we investigated the effects of knocking down the PSCA on the cell migration, the invasiveness, and the EMT of the PCa cell line DU145 in vitro and in vivo.

Methods

Four target sequences of the small hairpin RNA for PSCA were designed, and the best effect knockdown sequence shRNA#1 was screened to construct the stable transfected DU145 cell line (DU145 shRNA#1), the scramble sequence was also designed to construct the stable transfected DU145 cell line(DU145 scramble). Cell migration and invasion were studied using Transwell assay. Quantitative RT-PCR, Western blot (WB) were used to quantify PSCA, E-cadherin, β-catenin, Vimentin, Fibronectin expression in DU145, DU145 scramble, DU145 shRNA#1 in vitro and in vivo. RT-PCR, immunofluorescent staining were used to quantify PSCA, E-cadherin, and Vimentin expression in vitro. EMT-related genes Snail, Slug, and Twist, were quantified by quantitative RT-PCR in vitro.

Results

The constructed stable knockdown of the PSCA in the DU145 cell had a silencing effect up to 90.5 %. DU145 shRNA#1 became scattered from the tightly packed colonies. It was associated with decreased cell migration and invasion. There was also an increased Vimentin and Fibronectin expression, an inhibited E-cadherin and β-catenin expression at both the mRNA and the protein levels when compared to the DU145 and the DU145 scramble in vitro and vivo. Furthermore, with the exception of the Snail, the expression of EMT-related Slug and Twist genes were upregulated.

Conclusions

Our data indicated that knockdown of PSCA induced EMT and reduced metastatic potentials of the DU145 cells, suggesting that PSCA played an important role in prostatic carcinogenesis and progression.