Human Prostate Epithelial Cancer Cell Research Articles

Synthesis of lactones from fatty acids by ring-closing metathesis and their biological evaluation

The present study involves the synthesis of macrocyclic lactones by the esterification of unsaturated fatty acids (oleic acid, undecenoic acid, and erucic acid) with unsaturated alcohols (allyl alcohol, prop-2-ene-1-ol, oleyl alcohol, and undecenol) followed by a ring closing metathesis reaction employing Grubbs' second generation catalyst (1.0-1.5 mmol). The structure of the compounds was confirmed by 1H NMR, 13C NMR, FT-IR, and ESI-Mass spectral studies. The antibacterial activity of the synthesised lactones was evaluated. The larger ring-sized lactone, namely, erucic acid lactone, exhibited excellent antibacterial activity against three bacterial cell lines, namely, Staphylococcus aureus, Staphylococcus epidermidis, and Bacillus subtilis. Undecenoic acid-based lactones exhibited excellent antibacterial activity selectively against only Staphylococcus epidermidis. The assay of macrolactones for their in vitro anticancer activity was carried out by MTT for different cancer cell lines, namely, human prostate epithelial cancer cells (ATCC HTB-81), HepG2 derived from hepatic cancer cells (ATCC HB-8065), SKOV3 derived from human ovarian cancer cells (ATCC HTB-77), MDAMB-231 derived from human breast cancer cells (ATCC HTB-26) and Chinese hamster ovarian (CHO-K1) cell lines. The molecules selectively exhibited anticancer activity against Chinese hamster ovarian (CHO-K1) cell lines. Among macrolactones, (E)-oxacyclotridec-11-en-2-one (MALUN) was more active and its activity was much higher compared to others and on par with the reference standard Mitomycin C. This was followed by (E)-oxacyclotricos-14-en-2-one (MOLER) and (E)-oxacyclononadec-10-en-2-one (MOLOH). The fatty acid-based cyclic lactones with selective antibacterial and anticancer activities can be further explored for a variety of pharmaceutical formulations.

The Transcription Factor ERG Regulates Super-Enhancers Associated With an Endothelial-Specific Gene Expression Program.

The ETS (E-26 transformation-specific) transcription factor ERG (ETS-related gene) is essential for endothelial homeostasis, driving expression of lineage genes and repressing proinflammatory genes. Loss of ERG expression is associated with diseases including atherosclerosis. ERG's homeostatic function is lineage-specific, because aberrant ERG expression in cancer is oncogenic. The molecular basis for ERG lineage-specific activity is unknown. Transcriptional regulation of lineage specificity is linked to enhancer clusters (super-enhancers). To investigate whether ERG regulates endothelial-specific gene expression via super-enhancers. Chromatin immunoprecipitation with high-throughput sequencing in human umbilical vein endothelial cells showed that ERG binds 93% of super-enhancers ranked according to H3K27ac, a mark of active chromatin. These were associated with endothelial genes such as DLL4 (Delta-like protein 4), CLDN5 (claudin-5), VWF (von Willebrand factor), and CDH5 (VE-cadherin). Comparison between human umbilical vein endothelial cell and prostate cancer TMPRSS2 (transmembrane protease, serine-2):ERG fusion-positive human prostate epithelial cancer cell line (VCaP) cells revealed distinctive lineage-specific transcriptome and super-enhancer profiles. At a subset of endothelial super-enhancers (including DLL4 and CLDN5), loss of ERG results in significant reduction in gene expression which correlates with decreased enrichment of H3K27ac and MED (Mediator complex subunit)-1, and reduced recruitment of acetyltransferase p300. At these super-enhancers, co-occupancy of GATA2 (GATA-binding protein 2) and AP-1 (activator protein 1) is significantly lower compared with super-enhancers that remained constant following ERG inhibition. These data suggest distinct mechanisms of super-enhancer regulation in endothelial cells and highlight the unique role of ERG in controlling a core subset of super-enhancers. Most disease-associated single nucleotide polymorphisms from genome-wide association studies lie within noncoding regions and perturb transcription factor recognition sequences in relevant cell types. Analysis of genome-wide association studies data shows significant enrichment of risk variants for cardiovascular disease and other diseases, at ERG endothelial enhancers and super-enhancers. The transcription factor ERG promotes endothelial homeostasis via regulation of lineage-specific enhancers and super-enhancers. Enrichment of cardiovascular disease-associated single nucleotide polymorphisms at ERG super-enhancers suggests that ERG-dependent transcription modulates disease risk.

Abstract 1849: CXXC5 is overexpressed in human prostate epithelial cancer cell lines in culture and human prostate cancer tissue

Abstract Background: CXXC5 encodes a retinoid-inducible nuclear factor that plays an essential role in human hematopoiesis (1, 2). We have previously identified the differential expression of this gene in rat cancer cell lines with different cancer phenotypes (3). However, knowledge on the expression of this gene in human prostate cell lines or tissue is lacking, both at the transcript and protein level. Methods: Prospective study conducted between January-2012 through June-2015 at the University of Cartagena, Colombia. Expression of CXXC5 was evaluated by quantitative PCR, both in prostate cancer cell lines and tissue biopsies from patients undergoing transrectal ultrasound-guided prostate needle biopsy for suspected prostate cancer (PCa). A total of 65 prostate tissue samples, consisting of 24 benign prostatic tissue biopsies and 41 prostate cancer tissue biopsies were included in the study. Transcript levels in individual biopsies from each group were normalized to transcript levels of beta-actin of the corresponding sample and compared. The protein expression level of CXXC5 was analyzed by immunohistochemistry in benign and malignant prostate tissue. A final score was determined by multiplying the highest intensity of staining by the mean percentage of positive cells stained to yield a value between 0 and 300 for each case. For statistical analysis we compared parameters between group of cases with PCa and without PCa. This study was approved by the Ethical Review Board of the academic institution. Results: CXXC5 transcript expression levels were significantly lower in immortalized non-tumoral prostate cell line PWR-1E compared to PCa cell lines: LNCaP (Fold change: 10.5, p = 0.001), and PC3 (Fold change: 2.8, p = 0.014). In prostate tissue we observed a significant higher expression in low grade prostate cancer compared to benign prostate tissue (p = 0.034). IHC evaluation showed that CXXC5 staining was higher in tissue samples from patients with prostate cancer compared to patients with benign disease (p = <0.001). In the prostate cancer group, immunostaining was also stronger in malignant acini than in adjacent, benign acini, within the same patient sample. Conclusions: CXXC5 exhibits differential expression in prostate cell lines with different cancer phenotypes and between cancer and benign prostate tissue. Additional studies are required to determine the biological and clinical significance of CXXC5 in prostate cancer.

The small leucine rich proteoglycan fibromodulin is overexpressed in human prostate epithelial cancer cell lines in culture and human prostate cancer tissue

Fibromodulin is a small leucine-rich proteoglycan important for extracellular matrix organization and essential for tissue repair in multiple organs. The main function of this proteoglycan is the regulation of collagen fibrillogenesis; however, more recently described roles for fibromodulin have expanded to include regulation of angiogenesis, reprogramming of human fibroblasts into pluripotent cells, modulation of TGF-β activity, inflammatory processes and association with metastatic phenotypes. Additionally, fibromodulin has been identified as a novel tumor-associated antigen in leukemia, lymphoma, and leiomyoma. Knowledge about its expression in the prostate is limited. Fibromodulin expression was analyzed in two different malignant and one non-tumorigenic prostatic cell lines in culture, and in benign and malignant human prostate tissue. Expression was analyzed by real time PCR, immunocytochemistry, and immunohistochemistry. DNA sequencing was performed on a PCR fragment amplified with primers specific for the FMOD gene from cDNA obtained from the cultured cell lines. Both immunostaining and real time PCR analysis of cell lines indicated that fibromodulin was differentially expressed in the cancerous cell lines compared to the non-tumorigenic cell line. Likewise, cancerous tissue expressed significantly higher levels of intracellular fibromodulin compared to matched, benign tissue from the same patients, as well as compared to tissue from patients with only benign disease. The expression of fibromodulin was higher in prostatic cancer cells (cell-lines and human tissue) than in normal/benign prostatic cells. Additional studies are required to determine the biological and clinical significance and whether this proteoglycan has a role in carcinogenesis of the prostate or in prostate cancer related inflammatory processes.

Synergetic Bitherapy in Mice with Xenografts of Human Prostate Cancer Using a Methional Mimic (METLICO) and an Aldehyde Dehydrogenase 3 Inhibitor (MATE): Systemic Intraperitoneal (IP) and Targeted Intra-Tumoral (IT) Administration

An intraperitoneal (IP) monotherapy in nu/nu mice with subcutaneous xenografts of a human prostate epithelial cancer cell line:DU145 was undertaken with an aldehyde dehydrogenase 3 inhibitor MATE, that is a potent apoptogen on (DU145) in culture but not on their human prostate epithelial normal counterparts [13] . Tumour growth was slowed down but treatment had to be done 5days/week. To try to potentiate the action of MATE in vivo, a bitherapy was undertaken based on the synergetic apoptotic effect that had been observed previously in culture on DU145 treated with a methional mimic METLICO and DIMATE, an inhibitor of ALDH1 and ALDH3 [19]. The bitherapy with METLICO/MATE administered IP was as effective as the monotherapy with MATE alone by IP, but at a 2-fold lower dose of MATE and at a dose of METLICO that had no growth-inhibitory effect as a monotherapy . Hence there was definite synergism with bitherapy. To try to increase the efficacy of bitherapy, it was administered by the intra-tumoral (IT) route using the recently developed 20-bars-pressurized microinjection system from CERMA [16, 17]. IT administration of the bitherapy was indeed more effective than that by IP as regards tumour volumes are concerned. Histopathological analysis of IT-treated tumours confirmed that there were many necrotized zones but intact cells were still present. Approaches for treating a wider zone of tumour tissue by IT-bitherapy are discussed.

Aldehyde dehydrogenase inhibitors: α,β-Acetylenic N-substituted aminothiolesters are reversible growth inhibitors of normal epithelial but irreversible apoptogens for cancer epithelial cells from human prostate in culture

The pharmacomodulation of the N atom of α,β-acetylenic aminothiolesters or the replacement of the thiolester moiety by more electrophilic groups did not permit any clear rationale to be established for improving the selective growth-inhibitory activity of this family of compounds over that of the previously synthesized α,β-acetylenic aminothiolesters DIMATE and MATE [G. Quash, G. Fournet, J. Chantepie, J. Goré, C. Ardiet, D. Ardail, Y. Michal, U. Reichert, Biochem Pharmacol 64 (2002) 1279–92]. Hence DIMATE and MATE were investigated more thoroughly for selectivity and growth-inhibitory activity using human prostate epithelial normal cells (HPENC) on the one hand and human prostate epithelial cancer cells (DU145) on the other. Unequivocal evidence was obtained showing that both compounds were reversible growth inhibitors of HPENC but irreversible growth inhibitors of DU145. Growth-inhibition of DU145 was due to the induction of early apoptosis as revealed by the flow cytometric analytical profile of inhibitor-treated cells, of the decrease in the redox potential and increase in superoxide anion content of their mitochondria. Of the two intracellular enzymes: aldehyde dehydrogenases 1 and 3 (ALDH1 and ALDH3) targeted by DIMATE and MATE, ALDH3 was inhibited to the same extent by both compounds whereas ALDH1 was less susceptible to inhibition by MATE. As the induction of ALDH3 by xenobiotics is hormone-dependent, MATE, the more selective of the two inhibitors, is a useful tool not only for examining the role of the ALDH3 isoform in hormone-sensitive and resistant prostate cancer cells in culture but also for investigating if it can inhibit the growth of xenografts of prostate cancer in immunodeficient mice.

Establishment of an organotypic in vitro culture system and its relevance to the characterization of human prostate epithelial cancer cells and their stromal interactions

Human prostatic adenocarcinoma fragments (1–6 mm) were cultured on collagen sponges in medium supplemented or not supplemented with 4,5 α-dihydrotesterone (DHT) until 3 weeks, maintaining the three-dimensional (3D) epithelial and stromal organization present in the tumor in vivo. With time, in the presence of DHT, locally progressive cribriform nests of neoplastic cells with proliferative rates higher than those inside the fragment developed on the surface, while the stroma became more dissociated, and fibrosis replaced the muscular component. The 3D-culture provides a promising approach for studying the development and phenotype of prostate epithelial tumor progenitor cells and their stromal interactions.

NF- B inhibition increases chemosensitivity to trichostatin A-induced cell death of Ki-Ras-transformed human prostate epithelial cells

Chemoresistance has been one of the major problems in anticancer therapy. In our effort to find a potential molecular target for overcoming the chemoresistance in prostate cancer, a promising anticancer drug trichostatin A (TSA) induced cell death was found to be compromised by enhanced NF-kappaB activation in 267B1/K-ras human prostate epithelial cancer cells. However, both the NF-kappaB activation and chemoresistance were reduced by pretreatment with proteasome inhibitor-I (ProI), accompanied by accumulations of both IkappaBalpha and p65/RelA (but not p50/NF-kappaB1) in the cytoplasm. Clonogenic cell survival and soft agar assays further confirmed the increased TSA chemosensitivity of 267B1/K-ras cells by ProI treatment. Moreover, dominant negative mutant of IKKbeta, IkappaBalpha and p65 enhanced the chemosensitization, too. Unexpectedly, using LY294002 and PD98059, phosphatidylinositol-3-kinase and mitogen-activated protein kinase were also implied in TSA chemoresistance through NF-kappaB activation, while these compounds had showed no effect on radiosensitization in the cells. On the other hand, together with TUNEL (terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling) assay, activations of caspase-8 and caspase-3 by TSA and ProI were noticed, suggesting the involvement of apoptotic process in chemosensitization of 267B1/K-ras cells. Altogether, these results suggest that blocking the NF-kappaB activation pathway could be an efficient target for improving the TSA chemosensitization and applying to the development of anticancer therapeutics in Ki-Ras-overexpressing tumorigenic cells, including prostate cancer.