PC-3 Prostate Carcinoma Cells Research Articles

Antiproliferative and Apoptotic Effects of Murici (Byrsonima crassifolia (L.) Kunth and verbascifolia (L.) DC) and Taperebá (Spondias mombin L.) Extracts in Human Prostate Cell Line (PC-3).

The present study aimed to evaluate the antiproliferative and apoptotic effects of extracts obtained from the murici (Byrsonima crassifolia (L.) Kunth and verbascifolia (L.) DC) and taperebá (Spondias mombin L.) pulps, on cell proliferation, cell cycle and apoptosis on human prostate cell line (PC-3). Four extract was produced from the pulps: murici aqueous extract (MA), taperebá aqueous extract (TA), murici ethanolic extract (ME) and taperebá ethanolic extract (TE). In the present study, the analysis of cell viability, cell cycle and apoptosis analyze were performed using the MTT method and flow cytometry. The results showed that murici and taperebá extracts proved to be inhibitors of cell growth, modulation of cell cycle promoters and capable of enhancing the death in prostate carcinoma cells PC-3; suggesting a regulatory effect in prostate cell line, depending on type of extract and dosage used. These results open a series of perspectives on the use of these bioactive extracts in the prevention and treatment of prostate cancer.

Development of new TAK-285 derivatives as potent EGFR/HER2 inhibitors possessing antiproliferative effects against 22RV1 and PC3 prostate carcinoma cell lines

Epidermal growth factor receptor (EGFR) and human epidermal growth factor receptor 2 (HER2) protein tyrosine kinases co-expressed in various cancers such as ovarian, breast, colon, and prostate subtypes. Herein, new TAK-285 derivatives (9a–h) were synthesised, characterised, and biologically evaluated as dual EGFR/HER2 inhibitors. Compound 9f exhibited IC50 values of 2.3 nM over EGFR and 234 nM over HER2, which is 38-fold of staurosporine and 10-fold of TAK-285 over EGFR. Compound 9f also showed high selectivity profile when tested over a small kinase panel. Compounds 9a–h showed IC50 values in the range of 1.0–7.3 nM and 0.8–2.8 nM against PC3 and 22RV1 prostate carcinoma cell lines, respectively. Cell cycle analysis, apoptotic induction, molecular docking, dynamics, and MM-GBSA studies confirmed the plausible mechanism(s) of compound 9f as a potent EGFR/HER2 dual inhibitor with an effective antiproliferative action against prostate carcinoma.

Oxazolinyl derivatives of androst-16-ene as inhibitors of CYP17A1 activity and prostate carcinoma cells proliferation: Effects of substituents in oxazolinyl moiety

Steroid derivatives modified with nitrogen containing heterocycles are known to inhibit activity of steroidogenic enzymes, decrease proliferation of cancer cells and attract attention as promising anticancer agents. Specifically, 2′-(3β-hydroxyandrosta-5,16-dien-17-yl)-4′,5′-dihydro-1′,3′-oxazole 1a potently inhibited proliferation of prostate carcinoma cells. In this study we synthesized and investigated five new derivatives of 3β-hydroxyandrosta-5,16-diene comprising 4′-methyl or 4′-phenyl substituted oxazolinyl cycle 1 (b–f). Docking of compounds 1 (a–f) to CYP17A1 active site revealed that the presence of substitutents at C4′ atom in oxazoline cycle, as well as C4′ atom configuration, significantly affect docking poses of compounds in the complexes with enzyme. Testing of compounds 1 (a–f) as CYP17A1 inhibitors revealed that the only compound 1a, comprising unsubstituted oxazolinyl moiety, demonstrated strong inhibitory activity, while other compounds 1 (b–f) were slightly active or non active. Compounds 1 (a–f) efficiently decreased growth and proliferation of prostate carcinoma LNCaP and PC-3 cells at 96 h incubation; the effect of compound 1a was the most powerful. Compound 1a efficiently stimulated apoptosis and caused PC-3 cells death, that was demonstrated by a direct comparison of pro-apoptotic effects of compound 1a and abiraterone.

Single vesicle analysis of CD47 association with integrins and tetraspanins on extracellular vesicles released by T lymphoblast and prostate carcinoma cells.

CD47 regulates the trafficking of specific coding and noncoding RNAs into extracellular vesicles (EVs), and the RNA contents of CD47+ EVs differ from that of CD63+ EVs released by the same cells. Single particle interferometric reflectance imaging sensing combined with immunofluorescent imaging was used to analyse the colocalization of tetraspanins, integrins, and CD47 on EVs produced by wild type and CD47‐deficient Jurkat T lymphoblast and PC3 prostate carcinoma cell lines. On Jurkat cell‐derived EVs, β1 and α4 integrin subunits colocalized predominantly with CD47 and CD81 but not with CD63 and CD9, conserving the known lateral interactions between these proteins in the plasma membrane. Although PC3 cell‐derived EVs lacked detectable α4 integrin, specific association of CD81 with β1 and CD47 was preserved. Loss of CD47 expression in Jurkat cells significantly reduced β1 and α4 levels on EVs produced by these cells while elevating CD9+, CD63+, and CD81+ EVs. In contrast, loss of CD47 in PC3 cells decreased the abundance of CD63+ and CD81+ EVs. These data establish that CD47+ EVs are mostly distinct from EVs bearing the tetraspanins CD63 and CD9, but CD47 also indirectly regulates the abundance of EVs bearing these non‐interacting tetraspanins via mechanisms that remain to be determined.

Chemical Composition and Antioxidant, Antiviral, Antifungal, Antibacterial and Anticancer Potentials of Opuntia ficus-indica Seed Oil

Opuntia ficus-indica (OFI) is a cactus that is widely cultivated in the Kingdom of Saudi Arabia especially in the Taif region due to its favorable weather for growing, and it has benefits as a food and traditional medicine. The aim of the current study was to chemically characterize Opuntia ficus-indica seed oil from Taif, Kingdom of Saudi Arabia, using GC-MS and HPLC analysis and evaluate its antioxidant, antiviral, antifungal, antibacterial and anticancer activities. Linolenic acid was the dominating fatty acid in OFI oil, followed by oleic acid, linoleic acid, palmitic acid and stearic acid. Total tocopherol (α-, β-, Ɣ-tocopherol) was found to be 24.02 μg/mL. Campesterol was the main phytosterol, followed by γ- & β -sitosterol, and Stigmasterol. The phenolic components scored 30.5 mg gallic acid equivalent per ml of oil with 89.2% antioxidant activity (% DPPH radical inhibition) at 200 µL/mL of OFI oil. OFI oil showed an inhibition efficacy against microbial strains especially Saccharomyces cervisiae with a diameter (28.3 ± 0.4), MBC (15 µg/mL) and MIC bacteriostatic (10 µg/mL). While OFI oil had no effect against Aspergillus niger, OFI oil showed weak inhibitory activity against A-2780 (Ovarian carcinoma) cell line, although it showed significant inhibitory activity against PC-3 (Prostate carcinoma) cell line. OFI oil exhibited an antiviral effect (22.67 ± 2.79%) at 300 µg/mL of Oil against herpes simplex type 2 (HSV-2) virus. The bioactive compounds of OFI oil, as well as its main biological activities, make it a promising candidate for the non-communicable disease management.

The Antitumor Effect of Caffeic Acid Phenethyl Ester by Downregulating Mucosa-Associated Lymphoid Tissue 1 via AR/p53/NF-κB Signaling in Prostate Carcinoma Cells.

Simple SummaryThe effect of caffeic acid phenethyl ester (CAPE) on prostate cancer has not been thoroughly explored. CAPE downregulated the expression of androgen receptor (AR) and mucosa-associated lymphoid tissue 1 (MALT1) but enhanced that of p53, thus decreasing androgen-induced activation of MALT1 and prostate-specific antigen expressions in AR-positive prostate carcinoma cells. CAPE inhibited the activity of NF-κB in p53- and AR-negative prostate carcinoma cells. Although CAPE induced the ERK/JNK/p38/AMPKα1/2 signaling pathways, pretreatment with the corresponding inhibitors of MAPK or AMPK1/2 did not inhibit the CAPE effect on MALT1 blocking. Our results reveal that CAPE blocks the expression of the MALT1 gene to decrease the cell proliferation, invasion, and tumor growth of prostate carcinoma cells via the p53 and NF-κB signaling pathways, and they further verify that CAPE is an effective antitumor agent for human androgen-dependent and -independent prostate carcinoma cells by inhibiting MALT1 expression in vitro and in vivo.Caffeic acid phenethyl ester (CAPE), a honeybee propolis-derived bioactive ingredient, has not been extensively elucidated regarding its effect on prostate cancer and associated mechanisms. The mucosa-associated lymphoid tissue 1 gene (MALT1) modulates NF-κB signal transduction in lymphoma and non-lymphoma cells. We investigated the functions and regulatory mechanisms of CAPE in relation to MALT1 in prostate carcinoma cells. In p53- and androgen receptor (AR)-positive prostate carcinoma cells, CAPE downregulated AR and MALT1 expression but enhanced that of p53, thus decreasing androgen-induced activation of MALT1 and prostate-specific antigen expressions. p53 downregulated the expression of MALT in prostate carcinoma cells through the putative consensus and nonconsensus p53 response elements. CAPE downregulated MALT1 expression and thus inhibited NF-κB activity in p53- and AR-negative prostate carcinoma PC-3 cells, eventually reducing cell proliferation, invasion, and tumor growth in vitro and in vivo. CAPE induced the ERK/JNK/p38/AMPKα1/2 signaling pathways; however, pretreatment with the corresponding inhibitors of MAPK or AMPK1/2 did not inhibit the CAPE effect on MALT1 blocking in PC-3 cells. Our findings verify that CAPE is an effective antitumor agent for human androgen-dependent and -independent prostate carcinoma cells in vitro and in vivo through the inhibition of MALT1 expression via the AR/p53/NF-κB signaling pathways.

Isolation of asparaginase-producing microorganisms and evaluation of the enzymatic antitumor activity

Background L-asparaginase is an enzyme with very high biological activity owing to its activity on several tumor cells. It is mainly used to treat acute lymphoblastic leukemia. The complicated immunogenic adverse effects of present microbial sources present a need for switching to natural novel sources that have no immunogenic effect and better activity of L-asparaginase, so screening for other sources of L-asparaginase, like marine bacteria, may result in an enzyme having fewer adverse effects.Objective To screen and identify marine eco-friendly and potent L-asparaginase-producing bacteria, having a novel immunological property that possibly will avoid hypersensitivity.Materials and methods In the present study, bacterial strains were screened for extracellular L-asparaginase production from marine isolates, identified by 16 s rDNA technology, and L-asparaginase productivity was assessed using semiquantitative and quantitative enzymatic assays. The antiproliferative effect of the partially purified enzyme on different tumor human cell lines [HepG-2 (human hepatocellular carcinoma cell line), MCF-7 (breast cancer cell line), and PC-3 (prostate carcinoma cell line)] was assessed by the mitochondrial-dependent reduction of yellow MTT.Results and conclusion Bacillus safensis was established as the bacterial strain (Gene Bank accession number: MK541039). The extracellular enzyme-yielding capacity of the isolate B. safensis (518 IU/ml) was found to be 4.18 times higher than Bacillus pumilus (157.03 IU/ml) and higher than Bacillus circulans species (85 IU/ml). The marine isolate is environmentally friendly and can be used to produce significant quantities of extracellular L-asparaginase for the treatment of a variety of tumors and preparation of acrylamide-free fry food.

Evaluation of different internal standardization approaches for the quantification of melatonin in cell culture samples by multiple heart-cutting two dimensional liquid chromatography tandem mass spectrometry

We evaluate here different analytical strategies for the chromatographic separation and determination of N-acetyl-5-methoxytryptamine (MEL) and its oxidative metabolites N1-acetyl-N2-formyl-5-methoxykynuramine (AFMK), N1-acetyl-5-methoxykynuramine (AMK) and cyclic 3-hydroxymelatonin (c3OHM) in cell culture samples. Two dimensional liquid chromatography (2D-LC) in the multiple heart-cutting mode was compared with regular 1D chromatographic separations of MEL and its oxidative metabolites. Our results showed that the use of trifluoroacetic acid (TFA) as mobile phase modifier was required to obtain a satisfactory resolution and peak shapes particularly for c3OHM. As TFA is not compatible with ESI ionization the application of the MHC mode was mandatory for a proper chromatographic separation. We evaluate also different internal standardization approaches based on the combined use of a surrogate standard (5-methoxytryptophol) and an internal standard (6-methoxytryptamine) for MEL quantification in cell culture samples obtaining unsatisfactory results both by 1D- and 2D-LC-ESI-MS/MS (from 9 ± 2 to 186 ± 38%). We demonstrate that only the application of isotope dilution Mass Spectrometry through the use of an in house synthesized 13C isotopically labelled analogue provided quantitative MEL recoveries both by using 1D- and 2D-LC-ESI-MS/MS (99±1 and 98±1. Respectively) in androgen-insensitive human prostate carcinoma PC3 cells.

Co-administration of tyrosine kinase inhibitors with rottlerin in metastatic prostate cancer cells.

After prostatectomy due to prostate carcinoma, patients often develop metastases. Although prostate cancer is susceptible to hormonal manipulation, many patients become castration-resistant. Therefore, new therapies are the focus of investigations. We analyzed the effect of the tyrosine kinase inhibitors (TKIs), sorafenib and sunitinib, in combination with rottlerin, a PKCδ inhibitor, on metastatic mechanisms in prostate carcinoma cells. LNCaP and PC-3 prostate carcinoma cells were treated with sorafenib or sunitinib alone at various concentrations (1-20 µM) or in combination with rottlerin (10 µM) for 24 h. Then, cell toxicity (MTT test) and cell proliferation (BrdU incorporation assay) were quantified. The study demonstrated a dose-dependent inhibitory effect of sorafenib and sunitinib on PC-3 and LNCaP cell activity and proliferation. Both agents showed significantly stronger cytotoxic effects in LNCaP cells. At the highest concentrations, sorafenib and sunitinib inhibited the viability of LNCaP cells up to 2 % and 31 %, respectively, and the viability of PC-3 cell line up to 20 % and 43 %, respectively. The proliferation of both cell lines was significantly stronger inhibited by sorafenib than by sunitinib. In LNCaP cells, sorafenib and sunitinib at the highest concentrations inhibited cell proliferation up to 46 % and 49 %, respectively, and the proliferation of PC-3 line up to 40 % and 47 %, respectively. Rottlerin reduced the viability and proliferation of PC3 cells to 81 % and 42 %, whereas the viability and proliferation of LNCaP cells were reduced to 25 % and 57 %, respectively. Sorafenib and sunitinib at low concentrations partly neutralized the inhibitory effect of rottlerin on cell viability and proliferation. On the other hand, in PC-3 cells, rottlerin reduced the inhibitory effects of sorafenib and sunitinib at the highest concentrations on cell viability from 20 % to 30 % and from 43 % to 61 %, respectively. An additive effect on cell activity was observed after treating LNCaP cells with both sunitinib at high concentrations and rottlerin. This combination increased the cytotoxic effect from 31 % to 13 % at the highest sunitinib concentration. Our results showed that monotherapy with sorafenib was the most efficient in both PCa cell lines. A marginally additive effect of rottlerin was only observed in LNCaP cells treated with sunitinib at a high concentration. Sorafenib and sunitinib reduced cell migration in PC-3 cells to 10 % and 32 % of untreated cells, respectively. Co-treatment with sorafenib/sunitinib and rottlerin did not result in a significantly stronger anti-migratory effect than the treatment with each TKI alone. Given the strong cytotoxic effect of TKIs, especially sorafenib, on LNCaP cells, the results of the migration assay in this line were severely biased and not considered in the analysis. Unlike in other malignancies, combination therapy with TKI and rottlerin seems not beneficial in prostate cancer. More promising seems to be monotherapy with rottlerin, but further studies are needed to confirm this observation.

EGFR-mediated Rad51 expression potentiates intrinsic resistance in prostate cancer via EMT and DNA repair pathways

AimTo study the role of EGFR signaling in regulation of intrinsic resistance in prostate cancer. Materials and methodsRadioresistant prostate carcinoma DU145 and PC-3 cells were used to study the effect of shRNA-mediated knockdown of EGFR on intrinsic radioresistance mechanisms. Semi-quantitative PCR, western blotting, growth kinetics, colony formation, transwell migration, invasion and trypan blue assays along with inhibitors erlotinib, NU7441, B02, PD98059 and LY294002 were used. Key findingsEGFR knock-down induced morphological alterations along with reduction in clonogenic potential and cell proliferation in DU145 cells. Migratory potential of prostate cancer cells were reduced concomitant with upregulation of epithelial marker, E-cadherin and decreased expression of mesenchymal markers, vimentin and snail. Further, EGFR knock-down decreased the expression of Rad51 and DNA-PK at mRNA as well as protein levels. Likewise, erlotinib, an EGFR inhibitor, and NU7441, a DNA-PK inhibitor increased the expression of E-cadherin and decreased the level of vimentin. Both these inhibitors also decreased the levels of DNA damage regulatory protein Rad51. Further, Rad51 inhibitor, B02, inhibited the clonogenic potential, cell migration and reduced the expression of vimentin, Ku70 and Ku80, and also, B02 radiosensitized DU145 cells. EGFR-regulated expression of Rad51 was found to be mediated via PI3K/Akt and Erk1/2 pathways. SignificanceEGFR was found to regulate DNA damage repair, survival and EMT responses in prostate cancer cells through transcriptional regulation of Rad51. A novel role of EGFR-Erk1/2/Akt-Rad51 axis through modulation of EMT and DNA repair pathways in prostate cancer resistance mechanisms is suggested.

TU52. GENE EXPRESSION CHANGES ASSOCIATED WITH TRAJECTORIES OF PSYCHOPATHOLOGY IN A LONGITUDINAL COHORT OF CHILDREN AND ADOLESCENTS

Four new 4,5-dihydro-1,3-oxazole, and four new benzo-[d]-oxazole derivatives of [17(20)E]-21-norpregnene, differing in the structure of steroid moiety, were synthesized and evaluated for their potency to inhibit 17α-hydroxylase/17,20-lyase (CYP17A1) activity. Among new compounds, the only oxazolinyl derivative comprising 5-oxo-4,5-seco-3-yn- moiety potently inhibited CYP17A1. Binding modes of the oxazolinyl derivatives of [17(20)E]-21-norpregnene were analyzed by molecular dynamics simulations, and model of alternate, water-bridged type II interaction was proposed for these compounds. Eight new compounds, together with two CYP17A1-inhibiting oxazolinyl derivatives synthesized earlier, abiraterone and galeterone were evaluated for their potency to inhibit prostate carcinoma PC-3 and LNCaP cells growth. Oxazolinyl and benzoxazolyl derivatives comprising 3β-hydroxy-5-ene moieties potently inhibited prostate carcinoma cell growth; inhibitory potencies of 3-oxo-4-en- and 5-oxo-4,5-seco-3-yn- derivatives were significantly lower.

Effect of Different Alcoholic Beverages on Human Glioblastoma Cell Lines

Background: Anecdotal reports from neurosurgeons have suggested that glioblastoma patients that consumed moderate amounts of alcoholic beverages after glioblastoma surgery presented with improved vitality. Objective: This study aimed to investigate if any evidence for these anecdotal reports can be reproduced experimentally. Furthermore, we studied the effects of different alcoholic beverages on glioblastoma cells. Methods: GOS-3 glioblastoma cells and PC3 prostate carcinoma cells as control were incubated with beer, red wine, white wine, vodka, and whiskey at different concentrations. Membrane disruption by acute cytotoxicity and apoptosis induction was evaluated via Annexin-V-FITC flow cytometry and confocal laser scanning microscopy. Long-term effects on cell proliferation were studied by the XTT test. Results: There was no increased membrane disruption even at physiologically high alcohol concentrations of 1%. Cell proliferation was significantly inhibited by vodka and beer. Among the wines, the white wine caused slight proliferation inhibition in GOS-3 glioblastoma cells while inducing slightly enhanced proliferation in PC3 prostate cancer cells. After these first results, the study was expanded to more different brands of vodka and additional white and red wines from different grapes. While confirming the initial results, no additional differences between the different brands of vodka were observed. In the wine investigations, all the wines showed inhibition of cell proliferation during long-term incubation of three different glioblastoma cell lines. Consistently, the inhibition from red wines was lower than the inhibition from white and rosé wines. Conclusion: In conclusion, alcoholic beverages at concentrations used during the normal ingestion have both cytotoxic and antiproliferative effects on glioblastoma cells in vitro which could not be found in the controls with pure ethanol.

In vitro pro-apoptotic and anti-migratory effects of Treculia africana Decne. (Moraceae) and Entandrophragma angolense Welw (Meliaceae) extracts on prostate cancer cells

Prostate cancer is the second leading cause of cancer deaths in men and there is an increasing interest in chemoprevention to fight it. The authors sought a scientific rationale for the traditional use of six Cameroonian medicinal plants for the treatment of prostate inflammation/tumour. The prostate cells viability incubated with each ethanolic plant extract was determined after 24, 48 and 72 h using the MTT assay. The antitumor mechanisms of promising extracts [Treculia africana (TA) and Entandrophragma angolense (EA)] were further assessed by evaluating cell growth, cell proliferation, cell cycle, cell death mechanisms and cell migration. Only TA and EA significantly inhibited LNCaP, DU145 and PC3 prostate carcinoma cells growth and proliferation at the optimal concentrations (20–50 μg/mL). Furthermore, they significantly increased the number of apoptotic cells in PC3 cells at 20 μg/mL, while only TA significantly increased the number of G0/G1 cells in both DU145 and PC3 at 50 μg/mL. Cell cycle proteins (pcdk1, cdk2, pcdk2) were down-regulated by TA in both DU145 and PC3 cells. EA induced an overexpression of caspase-3 in both tested cells; meanwhile it induced an underexpression of cdk2. Apoptosis-related proteins Akt, pAkt and Bcl-2 were down-regulated in both DU145 and PC3 cells while caspase-3 was up-regulated following treatment with EA and TA. TA and EA inhibited cell chemotaxis and migration, while it increased cell adhesion to a fibronectin matrix. Taken altogether, these findings suggest that Treculia africana and Entandrophragma angolense might contain phyto-constituents which can be a promising strategy for the treatment of prostate cancer.

Co-localisation of intra-nuclear membrane type-1 matrix metalloproteinase and hypoxia inducible factor-2α in osteosarcoma and prostate carcinoma cells.

Increased membrane type-1 matrix metalloproteinase (MT1-MMP) expression in osteosarcoma is predictive of poor prognosis and directs bone metastasis in prostate carcinoma. MT1-MMP subcellular localisation varies with oxygen tension, and, therefore, the aim of the present study was to assess protein interactions between MT1-MMP and the hypoxia inducible factors (HIF-1α and HIF-2α). MT1-MMP protein expression was investigated across a panel of cancer cell lines, including a positive and negative control. The hypoxia-induced alteration in subcellular location of MT1-MMP, HIF-1α and HIF-2α in the U2OS osteosarcoma cell line was assessed using subcellular fractionation. A proximity ligation assay was utilised to assess protein to protein interactions in the osteosarcoma U2OS and prostate carcinoma PC3 cell lines. U2OS and PC3 cells exhibited a significantly increased intra-nuclear interaction between MT1-MMP and HIF-2α in response to hypoxia. The role of this warrants further investigation as it may unveil novel opportunities to target MT1-MMP, which is of particular significance for osteosarcoma since current treatment options are limited.

New Pieces in the Puzzle of uPAR Role in Cell Migration Mechanisms.

The urokinase (uPA) receptor (uPAR) plays a key role in cell migration. We previously showed that uPAR-negative HEK-293 cells efficiently migrate toward serum but, after uPAR ectopic expression, migrate only in a uPAR-dependent manner. In fact, migration of uPAR-transfected HEK-293 (uPAR-293) cells is impaired by anti-uPAR antibodies, without recovery of the uPAR-independent migration mechanisms formerly active. Prostate carcinoma PC3 cells, which express high endogenous uPAR levels, migrated only through a uPAR-dependent mechanism; in fact, the silencing of uPAR expression inhibited their migration. We hypothesize a crucial role of the uPAR glycosyl-phosphatidyl-inositol (GPI) tail, which promotes uPAR partitioning to lipid rafts, in uPAR-controlled cell migration. Here, we show that removal of the uPAR GPI-tail, or lipid rafts disruption by methyl-beta-cyclodextrin impairs migration of PC3 cells, incapable of uPAR-independent migration, whereas it restores uPAR-independent migration in uPAR-293 cells. We then show that, in PC3 cells, both uPAR signaling partners, β1 integrins and receptors for formylated peptides (FPRs), partly associate with lipid rafts. Inhibition of their interaction with uPAR impairs this association and impairs cell migration. Interestingly, blocking uPAR association with FPRs also impairs β1 integrin partitioning to lipid rafts, whereas blocking its association with β1 integrins has no effect on FPRs partitioning. On these bases, we propose that uPAR controls cell migration by connecting β1 integrins and FPRs and, through its GPI tail, by driving them into lipid rafts, thus promoting pro-migratory signals. uPAR-mediated partitioning of integrins to lipid rafts is strictly dependent on uPAR association with FPRs.

Abstract 6377: Curcumin analog GO-Y030 diminishes cancer stem cell population by inhibiting interaction of HSP70 with its substrates

Abstract It has been established that a cancer tissue contains, in general, a small subpopulation of cancer stem cells (CSCs) having tumor initiation capacity. Because CSCs are resistant to chemoradiotherapy and play important roles in cancer relapse and metastasis, strategies targeting CSCs are crucial for effective anticancer therapies. Curcumin (diferuloylmethane) isolated from the rhizome of the plant turmeric (Curcuma longa) is one of the most widely characterized phytochemicals and well known to suppress cancer cell proliferation, invasion, angiogenesis, and metastasis by regulating multiple cell signaling pathways. However, its bioavailability is limited due to poor absorption. To improve this disadvantage, Ohori et al. (Mol Cancer Ther 2006;5:2563-71.) synthesized a new curcumin analog GO-Y030 (1,5-bis(3,5-bis(methoxymethoxy)phenyl)-1,4-pentadiene-3-one), which has an about 30-fold greater growth-inhibitory effect than curcumin. In the current study, we verified the potency of GO-Y030 to act against CSC population. We first discovered that GO-Y030 could dose-dependently suppress a sphere-forming ability in human HuH7 hepatocellular carcinoma and human PC3 prostatic carcinoma cell lines. Interestingly, the specific inhibitor of the stress-inducible heat shock protein (HSP) 70 (also called HSP72, HSP70-1, or HSPA1A) exhibited effects similar to GO-Y030, i.e., inhibition of CSC sphere formation and upregulation of HSP70 and HSP40 protein expression. As this result suggested that target molecules of GO-Y030 might be HSP70 and its co-chaperones such as HSP40, we next performed in vitro HSP70/HSP40-mediated refolding activity assay and revealed that GO-Y030 efficiently inhibited HSP70/HSP40 chaperone activity. Finally, performing the substrate-binding assay, we have proven that GO-Y030 reduces the substrate-recognition and binding activity of HSP70. HSPs are molecular chaperones that function to prevent denaturation or unfolding of client proteins when they are threatened by stress or high temperature. Since CSCs by nature adapt to oxidative stress, mitochondrial dysfunction, and endoplasmic reticulum stress by enhancing synthesis of protein-folding chaperones, the function of HSP70/HSP40 is important for the maintenance of CSC population. Our data suggest that GO-Y030 should impair stress tolerance in CSCs by inhibiting the interaction of HSP70 with substrate proteins and disrupting the function of HSP70/HSP40 and thus should finally contribute to reduction of CSC population. Citation Format: Maya Suzuki, Yohei Yamamoto, Aki Nishijima, Hiroyuki Shibata, Yasufumi Omori. Curcumin analog GO-Y030 diminishes cancer stem cell population by inhibiting interaction of HSP70 with its substrates [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6377.

Triterpene glycosides from Silene odontopetala

Silene species are known for their use in traditional medicine in treating several diseases. To the authors’ knowledge there is no report on the chemical composition of S. odontopetala. Therefore, the phytochemical investigation of the methanol extract of S. odontopetala was carried out, leading to the isolation of six undescribed oleanane-type glycosides along with the known saponin azukisaponin IV. Their structures were elucidated by the analysis of 1D and 2D-NMR experiments, along with mass spectrometry analysis. The cytotoxic activity of oleanane-type saponins was evaluated against a small panel of cancer cell lines, including PC-3 (prostate carcinoma cells), MCF-7 (breast cancer cells), A549 (alveolar basal carcinoma cells), and HeLa (cervical carcinoma cells). Furthermore, the activity of isolated compounds against a normal cell line HEK-293, used for assessing their cytotoxicity, was evaluated.

G3BP1-linked mRNA partitioning supports selective protein synthesis in response to oxidative stress.

Cells limit energy-consuming mRNA translation during stress to maintain metabolic homeostasis. Sequestration of mRNAs by RNA binding proteins (RBPs) into RNA granules reduces their translation, but it remains unclear whether RBPs also function in partitioning of specific transcripts to polysomes (PSs) to guide selective translation and stress adaptation in cancer. To study transcript partitioning under cell stress, we catalogued mRNAs enriched in prostate carcinoma PC-3 cell PSs, as defined by polysome fractionation and RNA sequencing (RNAseq), and compared them to mRNAs complexed with the known SG-nucleator protein, G3BP1, as defined by spatially-restricted enzymatic tagging and RNAseq. By comparing these compartments before and after short-term arsenite-induced oxidative stress, we identified three major categories of transcripts, namely those that were G3BP1-associated and PS-depleted, G3BP1-dissociated and PS-enriched, and G3BP1-associated but also PS-enriched. Oxidative stress profoundly altered the partitioning of transcripts between these compartments. Under arsenite stress, G3BP1-associated and PS-depleted transcripts correlated with reduced expression of encoded mitochondrial proteins, PS-enriched transcripts that disassociated from G3BP1 encoded cell cycle and cytoprotective proteins whose expression increased, while transcripts that were both G3BP1-associated and PS-enriched encoded proteins involved in diverse stress response pathways. Therefore, G3BP1 guides transcript partitioning to reprogram mRNA translation and support stress adaptation.

New steroidal oxazolines, benzoxazoles and benzimidazoles related to abiraterone and galeterone

Seven new oxazoline, benzoxazole and benzimidazole derivatives were synthesized from 3β-acetoxyandrosta-5,16-dien-17-carboxylic, 3β-acetoxyandrost-5-en-17β-carboxylic and 3β-acetoxypregn-5-en-21-oic acids. Docking to active site of human 17α-hydroxylase/17,20-lyase revealed that all oxazolines, as well as benzoxazoles and benzimidazoles comprising Δ16 could form stable complexes with enzyme, in which steroid moiety is positioned similarly to that of abiraterone and galeterone, and nitrogen atom coordinates heme iron, while 16,17-saturated benzoxazoles and benzimidazoles could only bind in a position where heterocycle is located nearly parallel to heme plane. Modeling of the interaction of new benzoxazole and benzimidazole derivatives with androgen receptor revealed the destabilization of helix 12, constituting activation function 2 (AF2) site, by mentioned compounds, similar to one induced by known antagonist galeterone. The synthesized compounds inhibited growth of prostate carcinoma LNCaP and PC-3 cells at 96 h incubation; the potency of 2′-(3β-hydroxyandrosta-5,16-dien-17-yl)-4′,5′-dihydro-1′,3′-oxazole and 2′-(3β-hydroxyandrosta-5,16-dien-17-yl)-benzimidazole was superior and could inspire further investigations of these compounds as potential anti-cancer agents.

Bioguided identification of daucosterol, a compound that contributes to the cytotoxicity effects of Crateva adansonii DC (capparaceae) to prostate cancer cells.

Crateva adansonii DC (Capparaceae) is a shrub used to treat tumors in Cameroon. In our previous reports, a Crateva adansonii dichloromethane-methanol (DCM/MeOH) extract was shown to prevent chemically induced tumors in Wistar rats. To determine the bioactive principle of Crateva adansonii extract and to elucidate its underlying mechanism. An activity-guided fractionation was realized using MTT assay. To investigate if the bioactive compound daucosterol (CA2) accounted for the previously observed anticancer effects of the C. adansonii extract, it was tested on cell growth, cell proliferation, cell cycle, cell death mechanism and cell migration. In addition, cell cycle- and apoptosis-regulating proteins were assessed by Western blotting. Daucosterol (CA2), a steroid saponin, was identified as major anticancer principle of the C. adansonii extract. Daucosterol significantly inhibited LNCaP, DU145 and PC3 prostate carcinoma cell growth and proliferation at the optimal concentration of 1 μg/mL. It also significantly increased the number of late apoptotic (DU145) and apoptotic (PC3) cells. The number of cells in S phase increased in DU145, while the number of G0/G1 cells decreased. Cell cycle proteins (cdk1, pcdk1, cyclin A and B) were down-regulated in DU145 and PC3 cells, whereas only cdk2 was down-regulated in PC3 cells. Moreover, the anti-apoptotic Akt, pAKT and Bcl-2 proteins were down-regulated, while the pro-apoptotic protein Bax was up-regulated. CA2 induced anti-metastatic effects by decreasing chemotaxis and cell migration, while it increased cell adhesion to fibronectin and collagen matrix. These results suggest that daucosterol is the major active principle responsible at least in part for the anticancer effect of the extract of Crateva adansonii.