Prostate Cancer Cell Proliferation Research Articles

Celastrol attenuates the invasion and migration and augments the anticancer effects of olaparib in prostate cancer

BackgroundProstate cancer (PCa) is a leading malignancy among men globally, with rising incidence rates emphasizing the critical need for better detection and therapeutic approaches. The roles of HSP90AB1 and PARP1 in prostate cancer cells suggest potential targets for enhancing treatment efficacy.MethodsThis study investigated the overexpression of HSP90AB1 and PARP1 in prostate cancer cells and the impact of HSP90AB1 knockdown on the sensitivity of these cells to the PARP inhibitor olaparib. We also explored the combined effect of olaparib and celastrol, an HSP90 inhibitor, on the clonogenic survival, migration, proliferation, and overall viability of prostate cancer cells, alongside the modulation of the PI3K/AKT pathway. An in vivo PC3 xenograft mouse model was used to assess the antitumor effects of the combined treatment.ResultsOur findings revealed significant overexpression of HSP90AB1 and PARP1 in prostate cancer cells. Knockdown of HSP90AB1 increased cell sensitivity to olaparib. The combination of olaparib and celastrol significantly reduced prostate cancer cell survival, migration, proliferation, and enhanced cumulative DNA damage. Celastrol also downregulated the PI3K/AKT pathway, increasing cell susceptibility to olaparib. In vivo experiments demonstrated that celastrol and olaparib together exerted strong antitumor effects.ConclusionsThe study indicates that targeting both HSP90AB1 and PARP1 presents a promising therapeutic strategy for prostate cancer. The synergistic combination of celastrol and olaparib enhances the efficacy of treatment against prostate cancer, offering a potent approach to combat this disease.

MYO6 contributes to tumor progression and enzalutamide resistance in castration-resistant prostate cancer by activating the focal adhesion signaling pathway

BackgroundEnzalutamide (Enz) resistance is a poor prognostic factor for patients with castration-resistant prostate cancer (CRPC), which often involves aberrant expression of the androgen receptor (AR). Myosin VI (MYO6), one member of the myosin family, plays an important role in regulating cell survival and is highly expressed in prostate cancer (PCa). However, whether MYO6 is involved in Enz resistance in CRPC and its mechanism remain unclear.MethodsMultiple open-access databases were utilized to examine the relationship between MYO6 expression and PCa progression, and to screen differentially expressed genes (DEGs) and potential signaling pathways associated with the MYO6-regulated Enz resistance. Both in vitro and in vivo tumorigenesis assays were employed to examine the impact of MYO6 on the growth and Enz resistance of PCa cells. Human PCa tissues and related clinical biochemical data were utilized to identify the role of MYO6 in promoting PCa progression and Enz resistance. The molecular mechanisms underlying the regulation of gene expression, PCa progression, and Enz resistance in CRPC by MYO6 were investigated.ResultsMYO6 expression increases in patients with PCa and is positively correlated with AR expression in PCa cell lines and tissues. Overexpression of AR increases MYO6 expression to promote PCa cell proliferation, migration and invasion, and to inhibit PCa cell apoptosis; whereas knockdown of MYO6 expression reverses these outcomes and enhances Enz function in suppressing the proliferation of the Enz- sensitive and resistant PCa cells both in vitro and in vivo. Mechanistically, AR binds directly to the promoter region (residues − 503 to − 283 base pairs) of MYO6 gene and promotes its transcription. Furthermore, MYO6 activates focal adhesion kinase (FAK) phosphorylation at tyrosine-397 through integrin beta 8 (ITGB8) modulation to promote PCa progression and Enz resistance. Notably, inhibition of FAK activity by Y15, an inhibitor of FAK, can resensitize CRPC cells to Enz treatment in cell lines and mouse xenograft models.ConclusionsMYO6 has pro-tumor and Enz-resistant effects in CRPC, suggesting that targeting MYO6 may be beneficial for ENZ-resistant CRPC therapy through the AR/MYO6/FAK signaling pathway.

Zinc ions activate AKT and promote prostate cancer cell proliferation via disrupting AKT intramolecular interaction.

Prostate is a zinc rich organ and the physiological function of the abundant zinc ions is relatively less understood. AKT kinase is a pivotal regulator downstream of cytokines, growth factors and other extracellular stimuli, and the attachment of its PH domain to PtdIns-3,4,5-P3 (PIP3) and the subsequent phosphorylation of its kinase domain by PDPK1 are considered important for its activation. Herein, we report a regulatory mechanism of AKT kinase by zinc ions. Mechanistically, zinc ions directly bind to AKT and facilitate AKT activation through disrupting the interaction between PH and kinase domains within AKT molecule. Consistently, AKT1-H89A/E91A mutant (zinc-binding-deficient) fails to respond to zinc ions and exhibits strong interaction between PH and kinase domains, and it is less oncogenic in orthotopic xenograft model of prostate cancer. On the other hand, the AKT1-W80L mutant with minimum intra-molecular interaction between PH and kinase domains shows strong tumor promoting capacity although it could not be further stimulated by zinc ions. Overall, this study reveals a distinctive regulatory mechanism of AKT activation and implies a tumor promoting role of the zinc ions in prostate cancer.

Expression and role of CNIH2 in prostate cancer.

Prostate cancer is one of the most common cancers in men and poses a significant threat to global male health. Traditional prostate cancer assessment methods have certain limitations, necessitating the identification of new prognostic factors and treatment targets. Our study revealed that low expression of the cornichon family AMPA receptor auxiliary protein 2 (CNIH2) gene was associated with a better progression-free survival rate in prostate cancer patients. The area under the receiver operating characteristic (ROC) curve (AUC) showed that the prognostic ability of the CNIH2 gene was high at 1, 3, and 5 years. The gene was an independent prognostic factor according to multivariate analysis. Functional verification experiments showed that knocking down the CNIH2 gene could inhibit the proliferation, migration and invasion of prostate cancer cells and could also inhibit tumor growth in nude mice. Our study is the first to reveal the important role of the CNIH2 gene in prostate cancer. This discovery provides a new research direction for individualized treatment and prognostic evaluation of prostate cancer.

Circ_0001047 inhibits prostate cancer progression and enhances abiraterone sensitivity via miR-122-5p/FKBP5/PHLPP1/AKT axis in vitro

Prostate cancer (PCa), with high heterogeneity and poor prognosis, is one of the most common malignant tumors in men. Circular RNAs (circRNAs) have been identified in tumor progression and resistance to medication in numerous studies. However, the role of circ_0001047 in PCa is unclear. In this research, we found that circ_0001047 had low expression in PCa cells and tissues and was negatively correlated with testosterone secretion in vivo. Overexpression of circ_0001047 inhibited the proliferation, migration, invasion, and anti-apoptotic abilities of human PCa cells in vitro. Mechanistically, circ_0001047 promoted the expression of FKBP5 through sponge adsorption of miR-122-5p and then inhibited the proliferation, anti-apoptotic migration, and invasion abilities of PCa cells. In addition, overexpression of circ_0001047 enhanced the sensitivity of PCa cells to abiraterone by inhibiting AKT phosphorylation activation through upregulation of FKBP5/PHLPP1. This study revealed a novel mechanism by which circ_0001047 regulates PCa progression and treatment sensitivity via the miR-122-5p/FKBP5/PHLPP1/AKT axis. These findings deepen our comprehension of the molecular mechanisms in latent PCa progression and treatment resistance.Graphical

Downregulation of hsa_circ_0006620 inhibits the malignant progression of prostate cancer by regulation of the miR-502-3p/HK2 axis mediated by aerobic glycolysis.

Circular RNAs (circRNA) are a class of covalently-closed, single-stranded RNAs that have been implicated in cancer progression due to their regulation of metabolism. However, the roles of circRNA in prostate cancer remain largely unknown. In this study, fluorescence in situ hybridization and RT-qPCR were used to investigate hsa_circ_0006620 expressions in both prostate cancer cells and tissues, after high-throughput sequencing. The luciferase reporter assay was used to identify hsa_circ_0006620 downstream targets. Transwell migration assays, 5-ethynyl-20-deoxyuridine assays, and Cell Counting Kit-8assays were used to investigate both proliferation and migration. In vivo tumorigenesis and metastasis assays were performed to investigate the role of hsa_circ_0006620 in prostate cancer. The results showed that hsa_circ_0006620 expression increased in prostate cancer cells and tissues. Hsa_circ_0006620 downregulation inhibited prostate cancer cell proliferation as well as in vivo and in vitro migrations. The luciferase results validated that miR-502-3p and hexokinase 2 (HK2) were hsa_circ_0006620 downstream targets. HK2 overexpression or miR-502-3p inhibition reversed prostate cancer cell migration after hsa_circ_0006620 silencing. The study also found that overexpression of HK2 or inhibition of prostate cancer reversed aerobic glycolysis after hsa_circ_0006620 silencing. In summary, the results showed thathsa_circ_0006620 downregulation inhibited prostate cancerby regulation of the miR-502-3p/HK2 axis mediated by aerobic glycolysis.

The Hexosamine Biosynthetic Pathway alters the cytoskeleton to modulate cell proliferation and migration in metastatic prostate cancer.

Castration-resistant prostate cancer (CRPC) progresses despite androgen deprivation therapy, as cancer cells adapt to grow without testosterone, becoming more aggressive and prone to metastasis. CRPC biology complicates the development of effective therapies, posing challenges for patient care. Recent gene-expression and metabolomics studies highlight the Hexosamine Biosynthetic Pathway (HBP) as a critical player, with key components like GNPNAT1 and UAP1 being downregulated in metastatic CRPC. GNPNAT1 knockdown has been shown to increase cell proliferation and metastasis in CRPC cell lines, though the mechanisms remain unclear. To investigate the cellular basis of these CRPC phenotypes, we generated a CRISPR-Cas9 knockout model of GNPNAT1 in 22Rv1 CRPC cells, analyzing its impact on metabolomic, glycoproteomic, and transcriptomic profiles of cells. We hypothesize that HBP inhibition disrupts the cytoskeleton, altering mitotic progression and promoting uncontrolled growth. GNPNAT1 KO cells showed reduced levels of cytoskeletal filaments, such as actin and microtubules, leading to cell structure disorganization and chromosomal mis-segregation. GNPNAT1 inhibition also activated PI3K/AKT signaling, promoting proliferation, and impaired cell adhesion by mislocalizing EphB6, enhancing migration via the RhoA pathway and promoting epithelial-to-mesenchymal transition. These findings suggest that HBP plays a critical role in regulating CRPC cell behavior, and targeting this pathway could provide a novel therapeutic approach.

7886 Impact of Withania somnifera (Ashwagandha) Supplement on Androgen Signalling Pathways

Abstract Disclosure: I.S. Barata: None. J. Yakubu: None. T. Du Toit: None. A.V. Pandey: None. Supplements derived from plant extracts are often used as alternatives to pharmaceutical drugs. These products are often perceived as safe despite the absence of scientific evidence regarding their efficacy and safety and are less strictly regulated than pharmaceutical products. Winter cherry (Withania somnifera, commonly known as ashwagandha) is used as a testosterone booster supplement in multiple countries. Withania somnifera extract was found to increase testosterone and androgen precursors in a small clinical study. However, there is a lack of data regarding effects of Withania somnifera on the steroidogenic pathways. Steroidogenesis impacts not only sexual differentiation, reproduction, and fertility but also other physiological processes, including hypertension and obesity. Moreover, the modulation of hormone signaling is an important target in hormone-responsive pathogenesis, and overproduction of androgens has been implicated in the pathogenesis of prostate cancer (PCa) and polycystic ovarian syndrome (PCOS). In humans, testosterone is mainly produced in the testes after conversion of pregnenolone to 17-hydroxypregnenolone (17-OHPreg) and dehydroepiandrosterone (DHEA, the precursor of androgens) by adrenal CYP17A1, which catalyzes both the 17-hydroxylation of steroids for cortisol production and the breakage of 17,20 bonds (17,20 lyase) in 17-OHPreg to produce DHEA. The intake of substances that may increase androgen levels by people with PCa or PCOS or with predisposition to these conditions may trigger pathogenesis or worsen prognosis by accelerating disease progression. We investigated the effects of Withania somnifera in modulating the adrenal steroidogenic pathway and the possible consequences on the pathogenesis of androgen-responsive conditions, specifically PCa. Adrenal cells were treated with the extract of Withania somnifera to characterize its effect on adrenal steroid profile and CYP17A1 hydroxylase and lyase activities. Prostate cancer proliferation was assessed by direct incubation of prostate cancer cells with extracts as well as with conditioned media from adrenal cells treated for 48h, to simulate natural steroidogenesis. The results suggest that adrenal steroid hormone biosynthesis can be altered by the intake of Withania somnifera extract and that this supplement may affect proliferation of PCa cells. Moreover, the reported testosterone booster effect of Withania somnifera supplementation does not appear to be through increased adrenal androgen production. Presentation: 6/1/2024

7886 Impact of Withania somnifera (Ashwagandha) Supplement on Androgen Signalling Pathways

Abstract Disclosure: I.S. Barata: None. J. Yakubu: None. T. Du Toit: None. A.V. Pandey: None. Supplements derived from plant extracts are often used as alternatives to pharmaceutical drugs. These products are often perceived as safe despite the absence of scientific evidence regarding their efficacy and safety and are less strictly regulated than pharmaceutical products. Winter cherry (Withania somnifera, commonly known as ashwagandha) is used as a testosterone booster supplement in multiple countries. Withania somnifera extract was found to increase testosterone and androgen precursors in a small clinical study. However, there is a lack of data regarding effects of Withania somnifera on the steroidogenic pathways. Steroidogenesis impacts not only sexual differentiation, reproduction, and fertility but also other physiological processes, including hypertension and obesity. Moreover, the modulation of hormone signaling is an important target in hormone-responsive pathogenesis, and overproduction of androgens has been implicated in the pathogenesis of prostate cancer (PCa) and polycystic ovarian syndrome (PCOS). In humans, testosterone is mainly produced in the testes after conversion of pregnenolone to 17-hydroxypregnenolone (17-OHPreg) and dehydroepiandrosterone (DHEA, the precursor of androgens) by adrenal CYP17A1, which catalyzes both the 17-hydroxylation of steroids for cortisol production and the breakage of 17,20 bonds (17,20 lyase) in 17-OHPreg to produce DHEA. The intake of substances that may increase androgen levels by people with PCa or PCOS or with predisposition to these conditions may trigger pathogenesis or worsen prognosis by accelerating disease progression. We investigated the effects of Withania somnifera in modulating the adrenal steroidogenic pathway and the possible consequences on the pathogenesis of androgen-responsive conditions, specifically PCa. Adrenal cells were treated with the extract of Withania somnifera to characterize its effect on adrenal steroid profile and CYP17A1 hydroxylase and lyase activities. Prostate cancer proliferation was assessed by direct incubation of prostate cancer cells with extracts as well as with conditioned media from adrenal cells treated for 48h, to simulate natural steroidogenesis. The results suggest that adrenal steroid hormone biosynthesis can be altered by the intake of Withania somnifera extract and that this supplement may affect proliferation of PCa cells. Moreover, the reported testosterone booster effect of Withania somnifera supplementation does not appear to be through increased adrenal androgen production. Presentation: 6/1/2024

6667 IGF1 Induces The Expression of CYR61 In Metastatic Prostate Cancer

Abstract Disclosure: G.L. Ortiz Hernández: None. M. Walker: None. L. Woods-Burnham: None. R.A. Kittles: None. C.A. Casiano: None. S.L. Neuhausen: None. The cysteine-rich angiogenic inducer 61 (CYR61) is a member of the cellular communication network (CCN) protein family that can be induced by growth factors. CYR61-specific functions are dependent on cellular context. In prostate cancer (PCa), CYR61 contributes to cell growth and survival through its interactions with extracellular ligands, such as integrins avb3 and a6b4, in the extracellular matrix space. CYR61 contains an insulin-like growth factor-binding protein domain suggesting that it may interact with insulin-like growth factor-I (IGF1). High serum levels of IGF1 are directly linked to PCa development and recently have been studied as a predictor of metastatic disease. Given the important roles that IGF1 and CYR61 play in PCa and their potential interaction, it is critical to investigate their molecular interplay. The correlation between PCa aggressiveness and circulating levels of CYR61 and IGF1 is poorly studied. Our goal was to assess the contribution of the interaction of CYR61-IGF1 to PCa cell proliferation. Their combined role may explain a proportion of aggressive PCa. This study was designed to characterize the role of IGF1-induced expression of CYR61 in metastatic PCa cellular models and to determine if this interaction contributes to aggressive tumor properties (e.g., proliferation, migration, tumorsphere formation). Using immunoblotting, we demonstrated that CYR61 is upregulated in the metastatic cell line PC3. Furthermore, optimized knockdown of CYR61 using siRNA significantly reduced PC3 cell proliferation, viability, and prostasphere formation. To examine the underlying mechanisms associated with IGF1 signaling, we assessed the activation of either the PI3/Akt and MAPK pathways in PC3 cells with CYR61 silencing. CYR61 siRNA-mediated knockdown decreased activation of the PI3/Akt pathway but did not affect the MAPK pathway. In addition, we found that IGF1 induces protein expression of CYR61 in a time-dependent manner, validated by both immunoblotting and confocal microscopy. PC3 cell lines are androgen receptor negative (AR-) and glucocorticoid receptor positive (GR+), which is characteristic of aggressive, advanced metastatic castration-resistant prostate cancer (mCRPC). Currently, we are conducting the same experiments in LNCaP cells, which are AR+/GR-, to determine if the CYR61-IGF1 interplay also occurs in PCa cells capable of AR signaling. In conclusion, we found that CYR61 expression is induced by IGF1 and its inhibition decreased the capacity of metastatic PCa cells to proliferate. Our results suggest that CYR61 inhibition may have the potential for treating metastatic PCa. Presentation: 6/1/2024

6667 IGF1 Induces the Expression of CYR61 in Metastatic Prostate Cancer

Abstract Disclosure: G.L. Ortiz Hernández: None. M. Walker: None. L. Woods-Burnham: None. R.A. Kittles: None. C.A. Casiano: None. S.L. Neuhausen: None. The cysteine-rich angiogenic inducer 61 (CYR61) is a member of the cellular communication network (CCN) protein family that can be induced by growth factors. CYR61-specific functions are dependent on cellular context. In prostate cancer (PCa), CYR61 contributes to cell growth and survival through its interactions with extracellular ligands, such as integrins avb3 and a6b4, in the extracellular matrix space. CYR61 contains an insulin-like growth factor-binding protein domain suggesting that it may interact with insulin-like growth factor-I (IGF1). High serum levels of IGF1 are directly linked to PCa development and recently have been studied as a predictor of metastatic disease. Given the important roles that IGF1 and CYR61 play in PCa and their potential interaction, it is critical to investigate their molecular interplay. The correlation between PCa aggressiveness and circulating levels of CYR61 and IGF1 is poorly studied. Our goal was to assess the contribution of the interaction of CYR61-IGF1 to PCa cell proliferation. Their combined role may explain a proportion of aggressive PCa. This study was designed to characterize the role of IGF1-induced expression of CYR61 in metastatic PCa cellular models and to determine if this interaction contributes to aggressive tumor properties (e.g., proliferation, migration, tumorsphere formation). Using immunoblotting, we demonstrated that CYR61 is upregulated in the metastatic cell line PC3. Furthermore, optimized knockdown of CYR61 using siRNA significantly reduced PC3 cell proliferation, viability, and prostasphere formation. To examine the underlying mechanisms associated with IGF1 signaling, we assessed the activation of either the PI3/Akt and MAPK pathways in PC3 cells with CYR61 silencing. CYR61 siRNA-mediated knockdown decreased activation of the PI3/Akt pathway but did not affect the MAPK pathway. In addition, we found that IGF1 induces protein expression of CYR61 in a time-dependent manner, validated by both immunoblotting and confocal microscopy. PC3 cell lines are androgen receptor negative (AR-) and glucocorticoid receptor positive (GR+), which is characteristic of aggressive, advanced metastatic castration-resistant prostate cancer (mCRPC). Currently, we are conducting the same experiments in LNCaP cells, which are AR+/GR-, to determine if the CYR61-IGF1 interplay also occurs in PCa cells capable of AR signaling. In conclusion, we found that CYR61 expression is induced by IGF1 and its inhibition decreased the capacity of metastatic PCa cells to proliferate. Our results suggest that CYR61 inhibition may have the potential for treating metastatic PCa. Presentation: 6/1/2024

RBM15B Promotes Prostate Cancer Cell Proliferation via PCNA m6A Modification.

Prostate cancer (PC) is the most frequently occurring cancer in men, characterized by the abnormal proliferation of cells within the prostate gland. This study explores the role of RNA binding motif protein 15B (RBM15B) in PC. RBM15B expression levels in PC patients were predicted using the Starbase database. The expression of RBM15B and proliferating cell nuclear antigen (PCNA) expression in PC cells was detected. Following RBM15B knockdown, cell proliferation assays were conducted. N6-methyladenosine (m6A) levels in PC cells were quantified, and RNA immunoprecipitation was performed to analyze the binding of m6A and YTH N-methyladenosine RNA binding protein 1 (YTHDF1) on PCNA mRNA. The stability of PCNA mRNA was assessed after treatment with actinomycin D. An in vivo nude mouse xenograft model was created to validate the role of RBM15B. The findings revealed the upregulation of RBM15B in PC. RBM15B knockdown resulted in decreased proliferation, colony formation, and EdU-positive cells. Mechanical analysis showed that RBM15B facilitated m6A modification of PCNA mRNA, leading to increasing m6A methylation. YTHDF1 bound to these m6A sites on PCNA mRNA, thus stabilizing it. Furthermore, PCNA overexpression mitigated the effects of RBM15B knockdown on PC cell proliferation. In conclusion, RBM15B promotes PC cell proliferation by enhancing the stability of PCNA mRNA through YTHDF1-mediated m6A modification.

Pistacia vera and its Combination with Cisplatin: A Potential Anticancer Candidate by Modulating Apoptotic Genes.

Many bioactive phytochemicals have essential significance for handling various diseases and developing new drugs. The aim was to investigate the anti-tumor activity and the underlying mechanisms of pistachio pericarp extract (PPE) and pistachio kernel extract (PKE) alone and combined with cisplatin (CP) in the treatment of prostate cancer. The effects of the PPE, PKE, and CP alone and PPE and PKE in combination with CP (PPE+CP and PKE+CP) on the proliferation of PC-3 cells were determined using the MTT assay. The fold changes of BAX, BCL-2, P53, KLK2, TNF, TGF, and NANOG expression against β-actin were determined by real-time technique. Data were analyzed by two-way ANOVA and repeated measure tests. These research results indicated that a greater anti-proliferative effect of the PPE and PKE was shown in combination with CP compared with treatments using the PPE and PKE or CP alone. The extracts and Cisplatin in vitro had good synergistic effects on the inhibition of the proliferation of PC-3 cells. The IC50 values of PKE+CP were 4.141, 2.140, and 0.884 ug/mL, and PPE+CP were 2.754, 2.061, and 0.753 ug/mL after 24 h, 48 h, and 72 h treatment, respectively. Also, this result presented that the mRNA expression of BAX and P53 increased, and BCL-2, KLK2, TNF, TGF, and NANOG decreased in PC-3 cells. The finding of this research showed for the first time the anti-carcinogenesis effects of separately and in the combination of PPE, PKE, and CP on the PC-3 prostate cancer cells via modulating some genes and that it may be nominated for the herbal anti-cancer medications.

Periprostatic adipose tissue inhibits tumor progression by secreting apoptotic factors: A natural barrier induced by the immune response during the early stages of prostate cancer.

Prostate cancer (PCa) is the second most prevalent malignancy in men worldwide. The risk factors for PCa include obesity, age and family history. Increased visceral fat has been associated with high PCa risk, which has prompted previous researchers to investigate the influence of body composition and fat distribution on PCa prognosis. However, there is a lack of studies focusing on the mechanisms and interactions between periprostatic adipose tissue (PPAT) and PCa cells. The present study investigated the association between the composition of pelvic adipose tissue and PCa aggressiveness to understand the role played by this tissue in PCa progression. Moreover, PPAT-conditioned medium (CM) was prepared to assess the influence of the PPAT secretome on the pathophysiology of PCa. The present study included 50 patients with localized PCa who received robot-assisted radical prostatectomy. Medical records were collected, magnetic resonance imaging scans were analyzed and body compositions were calculated to identify the associations between adipose tissue volume and clinical PCa aggressiveness. In addition, CM was prepared from PPAT and perivesical adipose tissue (PVAT) collected from 25 patients during surgery, and its effects on the PCa cell lines C4-2 and LNCaP, and the prostate epithelial cell line PZ-HPV-7, were investigated using a cell proliferation assay and RNA sequencing (RNA-seq). The results revealed that the initial prostate-specific antigen level was significantly correlated with pelvic and periprostatic adipose tissue volumes. In addition, PPAT volume was significantly higher in patients with extracapsular tumor extension. PCa cell proliferation was significantly reduced when the cells were cultured in PPAT-CM compared with when they were cultured in control- and PVAT-CM. RNA-seq revealed that immune responses, and the cell death and apoptosis pathways were enriched in PPAT-CM-cultured cells indicating that the cytokines or other factors secreted from PPAT-CM induced PCa cell apoptosis. These findings revealed that the PPAT secretome may inhibit PCa cell proliferation by activating immune responses and promoting cancer cell apoptosis. This mechanism may act as a first-line defense during the early stages of PCa.

EphA-Mediated Regulation of Stomatin Expression in Prostate Cancer Cells.

Tumor growth and progression are affected by interactions between tumor cells and stromal cells within the tumor microenvironment. We previously showed that the expression of an integral membrane protein, called stomatin, was increased in cancer cells following their association with stromal cells. Additionally, stomatin impaired the Akt signaling pathway to suppress tumor growth. However, it remains unclear how stomatin expression is regulated. To explore this, we examined the cell surface molecules that can transduce the intercellular communication signals between cancer cells and stromal cells. Among these molecules, EphA3 and EphA7 receptors and their ligand ephrin-A5 were found to be expressed in prostate cancer cells, but not in prostate stromal cells. Cell-to-cell contact of prostate cancer cells through the EphA-ephrin-A interaction suppressed stomatin expression, while knockdown of EphA3/7 or ephrin-A5 increased stomatin expression. This increase contributed to an inhibition of prostate cancer cell proliferation. Intracellularly, the binding of ephrin-A to EphA attenuated extracellular signaling-regulated kinase (ERK) activation that promoted stomatin expression. Furthermore, ELK1 and ELK4, which are Ets family transcription factors phosphorylated by ERK, were involved in the induction of stomatin expression. We also found that higher Gleason score prostate cancer tissue samples had increased activation of EphA, while the stomatin expression and activated ERK and ELK levels were all low. In the mouse xenograft tumor samples generated by implantation of prostate cancer cells, EphA3 phosphorylation was attenuated and the ERK-ELK signaling and stomatin expression were enhanced in the area where stromal cells infiltrated the tumor. The EphA-mediated signaling suppresses the ERK-ELK pathway, leading to the reduction of stomatin expression that affects prostate cancer malignancy.

Comprehensive analysis of stearoyl-coenzyme A desaturase in prostate adenocarcinoma: insights into gene expression, immune microenvironment and tumor progression.

Prostate adenocarcinoma (PRAD) is a prevalent global malignancy which depends more on lipid metabolism for tumor progression compared to other cancer types. Although Stearoyl-coenzyme A desaturase (SCD) is documented to regulate lipid metabolism in multiple cancers, landscape analysis of its implications in PRAD are still missing at present. Here, we conducted an analysis of diverse cancer datasets revealing elevated SCD expression in the PRAD cohort at both mRNA and protein levels. Interestingly, the elevated expression was associated with SCD promoter hypermethylation and genetic alterations, notably the L134V mutation. Integration of comprehensive tumor immunological and genomic data revealed a robust positive correlation between SCD expression levels and the abundance of CD8+ T cells and macrophages. Further analyses identified significant associations between SCD expression and various immune markers in tumor microenvironment. Single-cell transcriptomic profiling unveiled differential SCD expression patterns across distinct cell types within the prostate tumor microenvironment. The Gene Ontology and Kyoto Encyclopedia of Genes and Genome analyses showed that SCD enriched pathways were primarily related to lipid biosynthesis, cholesterol biosynthesis, endoplasmic reticulum membrane functions, and various metabolic pathways. Gene Set Enrichment Analysis highlighted the involvement of elevated SCD expression in crucial cellular processes, including the cell cycle and biosynthesis of cofactors pathways. In functional studies, SCD overexpression promoted the proliferation, metastasis and invasion of prostate cancer cells, whereas downregulation inhibits these processes. This study provides comprehensive insights into the multifaceted roles of SCD in PRAD pathogenesis, underscoring its potential as both a therapeutic target and prognostic biomarker.

CAVPENET Peptide Inhibits Prostate Cancer Cells Proliferation and Migration through PP1γ-Dependent Inhibition of AKT Signaling.

Protein phosphatase 1 (PP1) complexes have emerged as promising targets for anticancer therapies. The ability of peptides to mimic PP1-docking motifs, and so modulate interactions with regulatory factors, has enabled the creation of highly selective modulators of PP1-dependent cellular processes that promote tumor growth. The major objective of this study was to develop a novel bioactive cell-penetrating peptide (bioportide), which, by mimicking the PP1-binding motif of caveolin-1 (CAV1), would regulate PP1 activity, to hinder prostate cancer (PCa) progression. The designed bioportide, herein designated CAVPENET, and a scrambled homologue, were synthesized using microwave-assisted solid-phase methodologies and evaluated using PCa cell lines. Our findings indicate that CAVPENET successfully entered PCa cells to influence both viability and migration. This tumor suppressor activity of CAVPENET was attributed to inhibition of AKT signaling, a consequence of increased PP1γ activity. This led to the suppression of glycolytic metabolism and alteration in lipid metabolism, collectively representing the primary mechanism responsible for the anticancer properties of CAVPENET. Our results underscore the potential of the designed peptide as a novel therapy for PCa patients, setting the stage for further testing in more advanced models to fully realize its therapeutic promise.

Silencing APLNR enhances the radiosensitivity of prostate cancer by modulating the PI3K/AKT/mTOR signaling pathway.

Aberrant expression of apelin receptor (APLNR) has been found to be involved in various cancers' development, however, its function in prostate cancer (PCa) remains unclear. The research aimed to investigate the role and potential mechanism of APLNR in PCa. The mRNA expression of APLNR was detected via qRT-PCR assay. PCa cell proliferation and apoptosis were determined through plate cloning and flow cytometry. In addition, the expression of apoptosis-related proteins (Bax, Bcl-2, and cleaved caspase-3) was evaluated using western blot. DNA damage marker (γ-H2AX) was analyzed by immunofluorescence and western blot. GSEA analysis was performed for seeking enrichment pathways of APLNR in PCa, and the protein levels of PI3K, p-PI3K, AKT, p-AKT, mTOR, and p-mTOR were tested using western blot. APLNR expression was up-regulated in PCa tissues and cells. Silencing APLNR enhanced the sensitivity of PCa cells to radiotherapy, which was manifested by inhibiting cell proliferation, promoting cell apoptosis, and promoting DNA damage. Next, silencing APLNR inhibited the PI3K/AKT/mTOR pathway. Specifically, 740Y-P (the PI3K/AKT/mTOR pathway activator) reversed the effects of silencing APLNR on PCa cell proliferation, apoptosis and DNA damage. Silencing APLNR inhibited cell proliferation, promoted cell apoptosis, and enhanced the radiosensitivity of PCa cells, which was involved in the PI3K/AKT/mTOR signaling pathway. This study is conducive to the deeper understanding of PCa and further provides a new perspective for the treatment of PCa.

LINC01857 promotes cell proliferation and migration while dampening cell apoptosis in pancreatic cancer by upregulating CDC42EP3 via miR-450b-5p

BackgroundPancreatic cancer (PC) is a devastating human malignancy with a poor survival outcome (5-year survival less than 10%). In recent years, the regulatory roles of long non-coding RNAs (lncRNAs) in various types of cancers have been widely reported. Based on bioinformatics analysis, LINC01857 is shown to be highly expressed in PC tissue. Nevertheless, the role of LINC01857 in PC is limitedly reported. Hence, this study aimed to explore the effects of lncRNA LINC01857 on PC cell process and the related mechanism. MethodsRT-qPCR and fluorescence in situ hybridization (FISH) assay were conducted to measure LINC01857 expression and distribution in PANC-1 and MIA PaCa-2 cells. Colony formation and wound healing assays as well as flow cytometry analyses were employed to estimate the proliferation, migration, and apoptosis of PC cells transfected with pcDNA3.1-LINC01857 or si-LINC01857 compared with the behavior of PC cells transfected with empty pcDNA3.1 vector (control) or si-negative control (NC). Furthermore, RNA pulldown and luciferase reporter assays were utilized to demonstrate the interaction of LINC01857 and miR-450b-5p or to validate the binding of miR-450b-5p and cell division cycle 42 effector protein 3 (CDC42EP3). ResultsLINC01857 was highly expressed in PANC-1 and MIA PaCa-2 cells in contrast to its expression in pancreatic ductal epithelial cells (8.9 folds and 7.1 folds, p<0.001). Silencing LINC01857 significantly reduced cell proliferation and migration while enhancing apoptosis (p<0.0005). In contrast, overexpression of LINC01857 markedly (p<0.05) accelerated these malignant behavior of PC cells. MiR-450b-5p was targeted and inversely regulated by LINC01857. Moreover, CDC42EP3 was verified to be targeted by miR-450b-5p, and CDC42EP3 was correlated to LINC01857 in a positive manner (p<0.001). Rescue experiments manifested that silencing CDC42EP3 effectively (p<0.05) reversed the promoting effect of LINC01857 on malignant behavior of PC cells. ConclusionLINC01857 promotes PC cell proliferation and migration while obstructing cell apoptosis by binding to miR-450b-5p and thus regulating CDC42EP3 expression. The study presents a novel and promising regulatory axis, which holds potential for the identification of biomarkers and development of therapeutic strategies for PC treatment.

Prevention of prostate cancer metastasis by a CRISPR-delivering nanoplatform for interleukin-30 genome editing

Prostate-cancer (PC) is a leading cause of cancer-related deaths in men worldwide. Interleukin-(IL)-30 is a PC-progression driver, and its suppression would be strategic for fighting metastatic disease. Biocompatible Lipid-Nanoparticles (NPs) were loaded with CRISPR/Cas9gRNA to delete human(h)IL30-gene and functionalized with anti-PSCA-Abs (Cas9hIL30-PSCA-NPs). Efficiency of the NPs in targeting IL30 and metastatic potential of PC cells was examined in vivo, in xenograft models of lung metastasis, and in vitro, by using 2-Organ-on-Chip (2-OC), containing 3D-spheroids of IL30+PC-Endothelial-Cell(EC) co-cultures in circuit with either Lung-mimicking-spheroids, or Bone-marrow(BM)-niche-mimicking-scaffolds. Cas9hIL30-PSCA-NPs demonstrated circulation stability, genome editing efficiency, without off-target effects and organ toxicity. Intravenous injection of three-doses/13-days, or five-doses/20-days, of NPs in mice bearing circulating PC cells and micro-emboli substantially hindered lung metastasization. Cas9hIL30-PSCA-NPs inhibited PC cell proliferation and expression of IL30 and metastasis-drivers, such as CXCR2, CXCR4, IGF1, L1CAM, METAP2, MMP2 and TNFSF10, whereas CDH1 was up-regulated. PC-Lung and PC-BM 2-OCs revealed that Cas9hIL30-PSCA-NPs suppressed PC cell release of CXCL2/GROβ, which in vivo was associated with intra-metastatic myeloid cell infiltrates, and of DKK1, OPG and IL6, which in vitro boosted endothelial-network formation and cancer cell migration. Development of a patient-tailored nanoplatform for selective CRISPR-mediated IL30 gene deletion is a clinically valuable tool against PC progression.