Pancreatic Cancer Cell Lines PANC-1 Research Articles

Yeni PDI tabanlı antiproliteratif kromoforlar

The primary objective of the work was to monitor the antiproliferative activity of two newly synthesized and described perylene diimides. The MTT test was used to investigate the antiproliferative effect against PC3 the prostat cancer cell line, Panc1 pancreatic cancer cell line, Saos2 osteosarcoma cell line, Hep3B hepatoma cell line and HUVEC non-cancerous human umbilical vein endothelial cells. To PC3, Panc1, and Saos 2 cells, both compounds were found to be considerably cytotoxic; however, a comparable impact was not seen in Hep3B cells. Compound 2 had the lowest IC50 value of 40,88 µg/ml and significantly inhibited PC3 cell proliferation when compared to other cell lines.

Thymoquinone affects the gemcitabine sensitivity of pancreatic cancer by regulating collagen via hypoxia inducible factor-1α.

Objective: To clarify the potential therapeutic effects of thymoquinone (TQ) on pancreatic cancer and its gemcitabine (GEM) sensitivity. Methods: The expression levels of hypoxia inducible factor-1α (HIF-1α), collagens (COL1A1, COL3A1, and COL5A1), and transforming growth factor-β1 (TGFβ1) in pancreatic cancer and para-carcinoma tissues were compared using immunohistochemical methods, and their relationships with TNM staging were analyzed. The effects of TQ on apoptosis, migration, invasion, and GEM sensitivity of pancreatic cancer cells were assessed using in vitro and in vivo experiments. Western blot and immunohistochemistry were used to detect the expression levels of HIF-1α, extracellular matrix (ECM) production pathway-related proteins, and TGFβ/Smad signaling pathway-related proteins. Results: The expression levels of HIF-1α, COL1A1, COL3A1, COL5A1, and TGFβ1 in pancreatic cancer tissues were significantly higher than those in para-carcinoma tissues and correlated with TNM staging (p < 0.05). TQ and GEM administration inhibited the migration and invasion of the human pancreatic cancer cell line PANC-1 and promoted the apoptosis of PANC-1 cells. The combination of TQ and GEM was more effective than GEM alone. Western blot analysis showed that the expression levels of HIF-1α, ECM production pathway-related proteins, and TGFβ/Smad signaling pathway-related proteins were significantly decreased when TQ was used to treat PANC-1 cells (p < 0.05), and the expression levels of these proteins in the TQ + GEM group were significantly more decreased than those in the GEM group. Overexpression or knockdown of HIF-1α in PANC-1 cells showed the same effects as those induced by TQ administration. In vivo experiments showed that in PANC-1 tumor-bearing mice, tumor volume and tumor weight in mice treated with GEM and TQ were significantly lower than those in control or GEM-treated mice, whereas cell apoptosis was significantly increased (p < 0.05). Western blot and immunohistochemistry results showed that the levels of HIF-1α, ECM production pathway-related proteins, and TGFβ/Smad signaling pathway-related proteins in the GEM + TQ treatment group were further decreased compared to the control group or the GEM treatment group (p < 0.05). Conclusion: In pancreatic cancer cells, TQ can promote apoptosis, inhibit migration, invasion, and metastasis, and enhance the sensitivity to GEM. The underlying mechanism may involve the regulation of ECM production through the TGFβ/Smad pathway, in which HIF-1α plays a key role.

Pancreatic Stromal Cell-derived Oncostatin M Confers Drug Resistance to a Multi-tyrosine Kinase Inhibitor in Pancreatic Cancer Cells.

Pancreatic cancer is known to have one of the worst prognoses of all cancers, and its tumor cells are highly resistant to chemotherapeutic drugs. Pancreatic cancer cells coexist with stromal cells; however, their involvement in anticancer drug resistance remains poorly understood. Thus, in this study, we analyzed drug sensitivity using an in vitro co-culture system containing pancreatic cancer cells and stromal cells treated with a compound library. We examined the viability of the pancreatic cancer cell lines BxPC-3, Capan-1, and Panc-1 against compounds in an in vitro co-culture model containing pancreatic stromal cells (PSCs) and analyzed the protein expression for drug resistance by western blotting. We found that co-cultured pancreatic cancer cells were resistant to vandetanib, which is an inhibitor of multi-tyrosine kinases. The key factor involved in drug resistance in these pancreatic cancer cells was oncostatin M, which was secreted by stromal cells. The addition of oncostatin M increased the vandetanib resistance of pancreatic cancer cells, while it inhibited the suppression of insulin receptor substrate-1 (IRS1) and the phosphorylation of extracellular signal-regulated kinase (ERK) by vandetanib. Oncostatin M secreted by stromal cells derived from the pancreas activates the IRS1-ERK axis, causing resistance to vandetanib.

Anticancer Activity of Sunitinib Analogues in Human Pancreatic Cancer Cell Cultures under Normoxia and Hypoxia

Pancreatic cancer remains one of the deadliest cancer types. It is usually characterized by high resistance to chemotherapy. However, cancer-targeted drugs, such as sunitinib, recently have shown beneficial effects in pancreatic in vitro and in vivo models. Therefore, we chose to study a series of sunitinib derivatives developed by us, that were proven to be promising compounds for cancer treatment. The aim of our research was to evaluate the anticancer activity of sunitinib derivatives in human pancreatic cancer cell lines MIA PaCa-2 and PANC-1 under normoxia and hypoxia. The effect on cell viability was determined by the MTT assay. The compound effect on cell colony formation and growth was established by clonogenic assay and the activity on cell migration was estimated using a 'wound healing' assay. Six out of 17 tested compounds at 1 µM after 72 h of incubation reduced cell viability by 90% and were more active than sunitinib. Compounds for more detailed experiments were chosen based on their activity and selectivity towards cancer cells compared to fibroblasts. The most promising compound EMAC4001 was 24 and 35 times more active than sunitinib against MIA PaCa-2 cells, and 36 to 47 times more active against the PANC-1 cell line in normoxia and hypoxia. It also inhibited MIA PaCa-2 and PANC-1 cell colony formation. Four tested compounds inhibited MIA PaCa-2 and PANC-1 cell migration under hypoxia, but none was more active than sunitinib. In conclusion, sunitinib derivatives possess anticancer activity in human pancreatic adenocarcinoma MIA PaCa-2 and PANC-1 cell lines, and they are promising for further research.

Library Screening and Preliminary Characterization of Synthetic Cannabinoids Against Prostate and Pancreatic Cancer Cell Lines.

Background: Our previous screening efforts with colorectal cancer cell lines suggested potential cannabinoid therapeutic leads for other solid cancers. Objectives: The aim of this study was to identify cannabinoid lead compounds that have cytostatic and cytocidal activities against prostate and pancreatic cancer cell lines and profile cellular responses and molecular pathways of select leads. Materials and Methods: A library of 369 synthetic cannabinoids was screened against 4 prostate and 2 pancreatic cancer cell lines with 48 h of exposure at 10 μM in medium with 10% fetal bovine serum using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) viability assay. Concentration titration of the top 6 hits was carried out to identify their concentration-response patterns and calculate IC50 values. Three select leads were examined for cell cycle, apoptosis, and autophagy responses. The role of cannabinoid receptors (CB1 and CB2) and noncanonical receptors in apoptosis signaling was examined with selective antagonists. Results: Two independent screening experiments in each cell line detected growth inhibitory activities against all six or a majority of cancer cell lines for HU-331 (a known cannabinoid topoisomerase II inhibitor), (±)5-epi-CP55,940, and PTI-2, each previously identified in our colorectal cancer study. 5-Fluoro NPB-22, FUB-NPB-22, and LY2183240 were novel hits. Morphologically and biochemically, (±)5-epi-CP55,940 elicited caspase-mediated apoptosis of PC-3-luc2 (a PC-3 subline with luciferase) prostate cancer and Panc-1 pancreatic cancer cell lines, each the most aggressive of the respective organ site. The apoptosis induced by (±)5-epi-CP55,940 was abolished by the CB2 antagonist, SR144528, but not modulated by the CB1 antagonist, rimonabant, and GPR55 antagonist, ML-193, nor TRPV1 antagonist, SB-705498. In contrast, 5-fluoro NPB-22 and FUB-NPB-22 did not cause substantial apoptosis in either cell line, but resulted in cytosolic vacuoles and increased LC3-II formation (suggestive of autophagy) and S and G2/M cell cycle arrests. Combining each fluoro compound with an autophagy inhibitor, hydroxychloroquine, enhanced the apoptosis. Conclusions: 5-Fluoro NPB-22, FUB-NPB-22, and LY2183240 represent new leads against prostate and pancreatic cancer cells in addition to the previously reported compounds, HU-331, (±)5-epi-CP55,940, and PTI-2. Mechanistically, the two fluoro compounds and (±)5-epi-CP55,940 differed regarding their structures, CB receptor involvement, and death/fate responses and signaling. Safety and antitumor efficacy studies in animal models are warranted to guide further R&D.

The inhibition of pancreatic cancer progression by PI3K-activated MSC proteomes

Background and Hypothesis:Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with a very poor survival rate. The PI3K pathway has been studied extensively in cancer cells which has led to the creation of PI3K inhibitor drugs. To explore an uncharted and counterintuitive use of the PI3K pathway, PI3K was activated in mesenchymal stem cells (MSCs) and the action of their conditioned medium (CM) on PDAC was examined. We hypothesized that PI3K-activated MSC-derived CM is capable of suppressing tumor growth and migration.&#x0D; Project Methods:To generate the treatment conditioned media, we first isolated and grew MSCs in DMEM + 10% serum and added 50 μM of PI3K activator (YS49) and incubated for 24 hours. Afterwards, we exchanged the media with fresh DMEM + 10% serum and incubated for another 24 hours. Next, we hyper-centrifuged the media to extract the conditioned media and used the media to treat PANC-1, PA03C, ASPC-1, PANC10.05, and PANC198 pancreatic cancer cell lines. In vitro viability and migration assays were conducted on these five treated cell lines. The regulatory mechanism was evaluated using Western blotting, immunoprecipitation, and ELISAs.&#x0D; Results:PI3K-activated MSC-derived CM reduced the proliferation (N=5) and migration (N=2) of PDAC (p &lt; 0.01). MSC CM was enriched with polyubiquitin C (Ubc), which acted as an extracellular tumor-suppressing protein by interacting with CXCR4. While the anti-tumor efficacy of Ubc differed depending on the CXCR4 expression level of PDAC, MSC CM was commonly effective in the tested cell lines and tissues (N=5).&#x0D; Conclusion and potential impact:Collectively, this study demonstrated that MSC CM can be converted into a tumor-suppressing agent by the activation of PI3K, and a Ubc-CXCR4 regulatory axis is at least in part responsible. The use of MSC CM treatment can potentially serve as an alternative or supplemental treatment to current chemotherapeutic agents in treating pancreatic cancer without inducing life-threatening side effects.

Ingenol mebutate inhibits the growth of pancreatic cancer cells in vitro via STING with an efficacy comparable to that of clinically used anticancer agents.

Pancreatic cancer is associated with a poor prognosis; thus, there is an urgent need to develop new and effective treatments. Ingenol mebutate (IM), which is isolated from the latex of Euphorbia peplus, was recently shown to be effective against pancreatic cancer cell lines; however, its mechanism of action has not been fully elucidated. In this study, we focused on the less drug-sensitive pancreatic cancer cell line Panc-1 and compared IM to commercially available anticancer drugs using cell survival assays. In addition, we aimed to identify novel biomolecules that may be involved in the mechanism of action of IM using RNA sequencing, western blotting, and inhibition assays. The IC50 values after 72h of exposure to IM and SN-38, drugs to which the Panc-1 cells are most sensitive among the tested anticancer agents, were 43.1 ± 16.8nM and 165 ± 37nM, respectively. IM showed a cytostatic effect equal to or greater than that of the clinically used pancreatic cancer therapeutic drugs. RNA sequencing and protein expression analysis revealed that expression of stimulator of interferon genes (STING) increased at low IM concentration, whereas cell viability decreased. Co-exposure of IM and STING inhibitor, H-151, to Panc-1 or MIA PaCa-2 cell lines canceled the growth-inhibitory effects of IM alone. In conclusion, IM may have an efficacy comparable to that of existing pancreatic cancer therapeutic agents on the less drug-sensitive Panc-1 cell line and the immune-related molecule STING plays a role in the mechanism of action of IM.

Identification of key pharmacological components and targets for Aidi injection in the treatment of pancreatic cancer by UPLC-MS, network pharmacology, and in vivo experiments

BackgroundPancreatic cancer is one of the most lethal cancers worldwide. Aidi injection (ADI) is a representative antitumor medication based on Chinese herbal injection, but its antitumor mechanisms are still poorly understood.Materials and methodsIn this work, the subcutaneous xenograft model of human pancreatic cancer cell line Panc-1 was established in nude mice to investigate the anticancer effect of ADI in vivo. We then determined the components of ADI using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) and explored the possible molecular mechanisms against pancreatic cancer using network pharmacology.ResultsIn vivo experiments, the volume, weight, and degree of histological abnormalities of implanted tumors were significantly lower in the medium and high concentration ADI injection groups than in the control group. Network pharmacology analysis identified four active components of ADI and seven key targets, TNF, VEGFA, HSP90AA1, MAPK14, CASP3, P53 and JUN. Molecular docking also revealed high affinity between the active components and the target proteins, including Astragaloside IV to P53 and VEGFA, Ginsenoside Rb1 to CASP3 and Formononetin to JUN.ConclusionADI could reduce the growth rate of tumor tissue and alleviate the structural abnormalities in tumor tissue. ADI is predicted to act on VEGFA, P53, CASP3, and JUN in ADI-mediated treatment of pancreatic cancer.

Interplay Between the Histone Variant H2A.Z and the Epigenome in Pancreatic Cancer

The oncogenic process is orchestrated by a complex network of chromatin remodeling elements that shape the cancer epigenome. Histone variant H2A.Z regulates DNA control elements such as promoters and enhancers in different types of cancer; however, the interplay between H2A.Z and the pancreatic cancer epigenome is unknown. This study analyzed the role of H2A.Z in different DNA regulatory elements. We performed Chromatin Immunoprecipitation Sequencing assays (ChiP-seq) with total H2A.Z and acetylated H2A.Z (acH2A.Z) antibodies and analyzed published data from ChIP-seq, RNA-seq, bromouridine labeling-UV and sequencing (BruUV-seq), Hi-C and ATAC-seq (Assay for Transposase-Accessible Chromatin using sequencing) in the pancreatic cancer cell line PANC-1. The results indicate that total H2A.Z facilitates the recruitment of RNA polymerase II and transcription factors at promoters and enhancers allowing the expression of pro-oncogenic genes. Interestingly, we demonstrated that H2A.Z is enriched in super-enhancers (SEs) contributing to the transcriptional activation of key genes implicated in tumor development. Importantly, we established that H2A.Z contributes to the three-dimensional (3D) genome organization of pancreatic cancer and that it is a component of the Topological Associated Domains (TADs) boundaries in PANC-1 and that total H2A.Z and acH2A.Z are associated with A and B compartments, respectively. H2A.Z participates in the biology and development of pancreatic cancer by generating a pro-oncogenic transcriptome through its posttranslational modifications, interactions with different partners, and regulatory elements, contributing to the oncogenic 3D genome organization. These data allow us to understand the molecular mechanisms that promote an oncogenic transcriptome in pancreatic cancer mediated by H2A.Z.

Piceatannol induces apoptotic cell death through activation of caspase-dependent pathway and upregulation of ROS-mediated mitochondrial dysfunction in pancreatic cancer cells.

Piceatannol is a naturally occurring plant-derived phenolic compound (stilbenoid), an analogue of resveratrol. It has been shown that, piceatannol has biological activity properties such as antiproliferative, antioxidative, anti-inflammatory and proapoptotic, in various human cancer studies in vitro and in vivo. In this study, it was aimed to investigate whether piceatannol induces apoptosis through anticancer activity methods (cell viability, colony formation, annexin-V/7-AAD, ROS (Reactive oxygen species), MMP (Mitochondrial membrane potential), wound healing, invasion assay, RT-qPCR (Real-Time Quantitative Polymerase Chain Reaction), western blotting in PANC-1 and MIA PaCa-2 pancreatic cancer (PC) cell lines. According to our results, piceatannol decreased cell viability in a dose and time-dependent manner [the half-maximal inhibitory concentration (IC50): 60 µM in PANC-1 and IC50: 90 µM in MIA PaCa-2 cell line at 48h (h)] and caused significant changes in the expression of apoptosis-related genes and protein. Piceatannol induced apoptosis in PANC-1 and MIA PaCa-2 cells, accompanied by increased ROS production, decreased MMP, and increased Caspase-3-9 activity. Piceatannol also inhibited colony-forming abilities, invasion, and migration of PC cells. Our results show that piceatannol has an anti-cancerogenic effect on PANC-1 and MIA PaCa-2 cells, and exerts this effect by suppressing proliferation and inducing apoptosis. Therefore, piceatannol could be considered to be a potential chemotherapeutic agent candidate for the treatment and prevention of PC.

Effects of cyclic acute and chronic hypoxia on the expression levels of metabolism related genes in a pancreatic cancer cell line.

The aim of this study was to characterize cycling hypoxia-induced changes in the expression of metabolism-related genes in the pancreatic cancer cell line PANC1. PANC1 cells were exposed to either 7 h cycles of hypoxia every other day for 20 cycles (cyclic acute hypoxia), or for 72 h cycles of hypoxia once a week for 5 cycles (cyclic chronic hypoxia). Changes in gene expression were profiled using reverse transcription-quantitative PCR and compared to cells cultured under normoxic conditions. Western blotting analysis confirmed upregulation of HIF1-α, glucose-6-phosphate isomerase, and ribokinase at the mRNA level. Upregulation in genes encoding enzymes involved in glycolysis was greater in cells cultured under cyclic acute hypoxia compared with cells cultured under chronic hypoxia including hexokinase2 and phosphoglycerate kinase 1. Genes encoding the pentose phosphate pathway (PPP) enzymes (transketolase and transaldolase) were upregulated to a similar degree. The expression of genes encoding pyruvate dehydrogenases that block pyruvate flow to the TCA cycle was significantly upregulated. Thus, exposure of PANC1 cells to acute hypoxia resulted in the upregulation of genes that shift the metabolism of cells towards glycolysis and the pentose phosphate pathway (PPP) in adaptation to hypoxic stress.

O081 Investigating the FLYWCH1/ β-catenin signalling in pancreatic cancer

Abstract Introduction β-catenin is a protein molecule of the E-cadherin/catenin adhesion complex that maintains epithelial cell-cell adhesion and intracellular signalling. The mutation and overexpression of β-catenin leads to cancer, including pancreatic ductal adenocarcinoma (PDAC). FLYWCH1 is a newly identified protein with zinc-finger type DNA-binding domain that interacts with nuclear β-catenin, leading to increased cell-cell and cell-matrix adhesion in cancer and stem cells. This study aimed to explore the roles of crosstalk between FLYWCH1 and Wnt/β-catenin signalling for the first time in pancreatic cancer cells. Methods We performed Western Blot analysis for the extraction of FLYWCH1/β-catenin, E-cadherin and GSK3-b in AsPc-1, PANC-1, and MIA PaCa-2 pancreatic cancer cell lines. Recommended concentrations of antibodies were used for the detection of proteins of interest. Tubulin was used as a loading control. Fluorescent detection was used, and the density of detected proteins were measured. Results Our results demonstrate evidence of differential expression of FLYWCH1 in pancreatic cancer cells. PANC-1 had less expression of FLYWCH1, but expression was moderate in AsPC-1. E-cadherin, β catenin, and GSK3-b were also expressed. These data suggest that FLYWCH1 levels correlated with unphosphorylated β-catenin to suppress the transcriptional product via controlling the aberrant Wnt/β-catenin pathway while E-cadherin promoted the cell-cell attachment. Conclusion These results suggest that Wnt1/β-catenin activity is negatively correlated with FLYWCH1 expression in pancreatic cancer cells. Thus, FLYWCH1 could have tumour suppressive activities. Future studies are required to elucidate their therapeutic and biomarkers efficacy. Take-home message FLYWCH1 is a newly identified protein could control B-catenin expression which leads tumour suppression. Thus, FLYWCH1 would be a therapeutic target for pancreatic cancer treatment in the future.

Abstract 1062: Antiproliferative activity of EC359, an inhibitor of leukemia inhibitory factor receptor (LIF-R), singly and in combination with chemotherapy drugs against pancreatic cancer cell lines

Abstract Although combination chemotherapy treatments such as FOLFIRINOX (5-fluorouracil, oxaliplatin, irinotecan), gem-abraxane (gemcitabine and nab-paclitaxel) and GTX (gemcitabine, docetaxel and capecitabine) have improved survival of pancreatic cancer patients incrementally, 5-year-survival for this disease remains dismal. New and more effective treatments are needed. Pancreatic stellate cells (PSCs), a form of fibroblasts that comprise much of the pancreatic tumor microenvironment, interact with the cancer cells via the cytokine leukemia inhibitory factor (LIF) and its receptor, LIF-R. This interaction contributes to tumor progression, survival, and resistance to various therapies, and is an important target for novel therapy. A small molecule inhibitor of LIF-R, EC359, inhibits growth of breast cancer cell line tumor explants in mice (Mol Cancer Ther 18: 1341-1354, 2019) and potentially modulates the activity of gemcitabine against such explants (Genes Cancer 10: 1-10, 2019). Given the involvement of the LIF axis in pancreatic cancer, EC359 was tested for its ability to inhibit proliferation of the human pancreatic cancer cell lines PANC-1, Capan-1, and Capan-2, and its possible influence on activity of chemotherapy drugs against these cell lines. Five-day drug exposures were conducted in 96-well plates. Relative cell density determined using vital stains (alamarBlue©, neutral red) was reported as a percent of the fluorescence/absorbance of control cultures. The 3 cell lines exhibited different sensitivities to EC359, with IC50 values ranging from 5 nM (Capan-1) to 150 nM (Capan-2). When combined with anti-pancreatic cancer standard-of-care drugs, EC359 yielded synergistic interactions in a concentration-dependent manner. Depending on the cell line, EC359 decreased the IC50 value for oxaliplatin by as much as 83%. Such enhancements of cytotoxicity for other drugs were up to 84% for docetaxel, 67% for paclitaxel, and 50% for irinotecan. EC359 was also synergistic with IBR120 (a novel small molecule inhibitor of RAD51) against PANC-1 cells. EC359 additively inhibited proliferation in combination with irinotecan or 5-FUdR. The nanomolar activity of EC359 against pancreatic cancer cell lines makes it a good candidate for potential treatment of this generally refractory disease. The synergistic interaction of EC359 with standard-of-care drugs provides an opportunity for increasing the therapeutic index for these agents, and ultimately improving clinical outcomes for pancreatic cancer and other cancers against which EC359 is currently in clinical trial. Citation Format: Peter J. Ferguson, Hareesh Nair, Mark D. Vincent, James Koropatnick. Antiproliferative activity of EC359, an inhibitor of leukemia inhibitory factor receptor (LIF-R), singly and in combination with chemotherapy drugs against pancreatic cancer cell lines [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1062.

Four new compounds with cytotoxic and neuroprotective activity from Notopterygium incisum

Phytochemical research on an extract of Notopterygium incisum yielded twenty-four compounds ( 1 – 24 ), including four new compounds 7 , 10 , 13 and 17 . The structures of new compounds were elucidated by spectroscopic analysis, and the absolute configuration of 5 were assigned via Mosher's method. In addition, compounds 2 , 9 , 19 and 24 were analyzed by single crystal X-ray analysis for the first time. The new compound 7 exhibited remarkable cytotoxic activity against the human pancreatic cancer cell lines PANC-1, CAPAN-2, CFPAC-1, and SW1990 with IC 50 values of 6.25 ± 0.54, 7.74 ± 1.12, 6.68 ± 1.11, and 5.35 ± 0.33 μM, respectively. The primary mechanistic study indicated that 7 caused cell death probably due to induced defects in the mitotic process. Moreover, compounds 2 and 7 - 9 effectively protected against H 2 O 2 -induced neurotoxicity in the SH-SY5Y cells, and 1 , 3 , 6 , 10 , 11 , 16 and 19 exhibited strong DPPH scavenging ability. • Four undescribed and twenty known compounds were reported. • Compound 7 displayed cytotoxicity against four pancreatic cancer cell lines. • Coumarins protected against H 2 O 2 -induced neurotoxicity in the SH-SY5Y cells.

P-47 Inhibition of phosphoprotein phosphatase 2A (PP2A) sensitizes pancreatic cancer to PARP inhibitors by modulation of homologous recombination repair

Pancreatic cancer remains one of the most difficult to treat cancers with a 5-years survival of less than 6%, representing one of the most lethal types of cancer, recent research has shown that PP2A inhibitors (LB-100) sensitize pancreatic cancer to chemotherapy and radiation. In addition, the finding from clinical trial study demonstrated that the effectiveness of single-agent Talazoparib for treatment of patients with and without germline BRCA1/2 mutation in ovarian, breast, small cell lung and Pancreatic cancers. The aim of this work was to Ι. investigate activity of LB-100 against pancreatic cancer cells as monotherapy and in combination with PARP inhibitions (Talazoparib). ΙΙ. Investigate the mechanism by which LB-100 and Talazoparib effect pancreatic cancer cells by studying effect of drugs on cell cycle and modulation of cell cycle regulatory proteins and assess the role of treatment combination in control DSB and HR repair through modulation of ATM phosphorylation. Human pancreatic cancer cell lines Panc-1, MIA-Pa-Ca-2 and BxPC-3 were obtained from European Collection of Authenticated Cell Culture (ECACC) and grown in either Dulbecco’s modified Eagle medium (DMEM) (MiaPaCa-2 and Panc-1) or RPMI medium (BxPC-3) with 10% FBS. Cell cultures were maintained in an atmosphere of 5% CO2/95% air at 37 C. PP2A activity was measured by PP2A Immunoprecipitation phosphatase assay Kit (Millipore), cell cytotoxicity were measured by MTT assay, cell cycle determined by flow cytometry. Western blot techniques were used to assess levels of proteins associated with regulation of cell cycle (Cdc2, p-Cdc2, and Cdc25c), apoptosis (caspase3) and DNA damage (γ-H2AX). Data are expressed as the mean ± (SEM) and analysed by an analysis of variance (ANOVA). The results show that LB-100 decreased PP2A activity in all pancreatic cancer cells in dose dependent manner. LB-100 significantly decreased cell viability of Panc-1, MIA-Pa-Ca-2 and BxPC-3 with IC50 (3.94 μM, 6.86 μM, and 10.87 μM) respectively. Interestingly adding 25 nm of Talazoparib further decreased IC50 in all cells (1.88 μM, 5.24 μM and 5.83 μM). Treatment combination attenuated pancreatic cancer cells growth through caspase activation and G2/M cell-cycle arrest. Combination therapy impaired cellular repair and induced DNA double-strand breaks by inducing Υ-H2AX. Our results suggest that treatment combination of LB100 and talazoparib in vitro inhibit cancer cells growth by modulation of the DNA damage response pathway and cell cycle checkpoint abrogation. The combination of PP2A inhibitor with PARP inhibitor has a synergistic effect in vitro. Further in vivo studies are needed to explore this combination as an effective option in the treatment of pancreatic cancer.

Solute Carrier Family 35 Member F2 Regulates Cisplatin Resistance and Promotes Malignant Progression of Pancreatic Cancer by Regulating RNA Binding Motif Protein 14.

We aimed to explore the role of Solute Carrier Family 35 Member F2 (SLC35F2) in pancreatic cancer (PCa) and to further study whether SLC35F2 regulates cisplatin resistance of PCa cells through the modulation of RNA binding motif protein 14 (RBM14) expression. SLC35F2 expression in 60 pairs of PCa tissues and adjacent ones was studied by RT-PCR analysis. Meanwhile, SLC35F2 expression levels in PCa cell lines were also evaluated by qPCR assay. In addition, SLC35F2 knockdown models were constructed in PCa cisplatin-resistant cells. Furthermore, we determined the interaction between SLC35F2 and RBM14 via luciferase assay. The findings of the present study demonstrated that SLC35F2 was significantly upregulated in PCa tissues. High level of SLC35F2 indicated higher incidence of metastasis and shorter survival rates. In vitro cell experiments revealed that knockdown of SLC35F2 suppressed cell invasion and metastasis capacity of cisplatin-resistant PCa cell lines PANC-1/DDP and CFPAC-1/DDP. It was also suggested that the key protein RBM14 in the SLC35F2 knockdown group was remarkably reduced. SLC35F2 can bind to RBM14 specifically. Overexpression of RBM14 partially reversed the effects of knockdown of SLC35F2 on the development of PCa. SLC35F2 expression in PCa tissues and cell lines is remarkably increased. In addition, it was also suggested that SLC35F2 may regulate cisplatin resistance of PCa cells through modulating RBM14 expression. In conclusion, it is conceivable from the study that SLC35F2 was remarkably upregulated in PCa and promoted the malignancy of PCa via regulating RBM14.

The K-Ras(G12D)-inhibitory peptide KS-58 suppresses growth of murine CT26 colorectal cancer cell-derived tumors

Mutations in the cell proliferation regulator K-Ras are found with a variety of cancer types, so drugs targeting these mutant proteins could hold great clinical potential. Very recently, a drug targeting the K-Ras(G12C) mutant observed in lung cancer gained regulatory approval and several clinical trials are currently underway to examine the efficacy of this agent when combined with other drugs such as a monoclonal antibody inhibitor of programmed cell death 1 receptor (anti-PD-1). Alternatively, there are currently no approved drugs targeting K-Ras(G12D), the most common cancer-associated K-Ras mutant. In 2020, we described the development of the K-Ras(G12D) inhibitory bicyclic peptide KS-58 and presented evidence for anticancer activity against mouse xenografts derived from the human pancreatic cancer cell line PANC-1 stably expressing K-Ras(G12D). Here, we show that KS-58 also possess anticancer activity against mouse tumors derived from the colorectal cancer cell line CT26 stably expressing K-Ras(G12D). Further, KS-58 treatment reduced phosphorylation of ERK, a major downstream signaling factor in the Ras pathway, confirming that KS-58 inhibits K-Ras(G12D) function. Unexpectedly; however, KS-58 did not show additive or synergistic anticancer activity with mouse anti-PD-1. Morphological analysis and immunostaining demonstrated no obvious differences in CD8+ cells infiltration or PD-L1 expression levels in CT26-derived tumors exposed to monotherapy or combination treatment. Nonetheless, KS-58 demonstrated reasonable stability in blood (t1/2 ≈ 30 min) and no obvious systemic adverse effects, suggesting clinical potential as a lead molecule against colorectal cancer.

Gemcitabine-Loaded Albumin Nanoparticle Exerts An Antitumor Effect on Gemcitabine-Resistant Pancreatic Cancer Cells Induced by MDR1 and MRP1 Overexpression in Vitro.

PurposeGemcitabine (GEM) is the first-line chemotherapeutic drug for pancreatic cancer treatment in clinical practice. However, many reasons can reduce the efficacy of GEM, among which the high expression of ATP-binding cassette (ABC) transporters is a significant factor. In this study, we aimed to investigate the antitumor effect of gemcitabine-loaded human serum albumin nanoparticle (GEM-HSA-NP) on GEM-resistant pancreatic cancer cells induced by the high expression of ABC transporters, namely multidrug resistance protein 1/P-gp/ABCB1 (MDR1) and multidrug resistance-associated protein 1/ ABCC1 (MRP1).MethodsMDR1 and MRP1 were stably overexpressed via lentiviral transduction in the pancreatic cancer cell lines BxPC3 and PANC1. Proliferation inhibition assays, cell cycle arrest and apoptosis analyses were conducted to examine the antitumor effect of GEM-HSA-NP. In addition, intracellular ATP levels were determined to explore the potential mechanisms implicated preliminarily.ResultsWhen administered to GEM-resistant cancer cells, GEM-HSA-NP displayed its antitumor effect by promoting the inhibition of proliferation, cell cycle arrest, and apoptosis induction. Intracellular ATP depletion, caused by the albumin component of GEM-HSA-NP was proposed to be potentially involved in the modulation of ABC transporter activity.ConclusionGEM-HSA-NP can effectively overcome GEM-resistance induced by MDR1 and MRP1 overexpression, which highlights its potential value in a clinical setting.

Alloferon Affects the Chemosensitivity of Pancreatic Cancer by Regulating the Expression of SLC6A14.

Pancreatic cancer (PCa), one of the most malignant solid tumors, has a high mortality rate. Although there have been many trials of chemotherapeutic drugs such as gemcitabine, the mortality rates remain significantly higher than for other types of cancer. Therefore, more effective ways of improving conventional therapy for PCa are needed. Cancer cells take up large amounts of glutamine to drive their rapid proliferation. Recent studies show that the amino acid transporter SLC6A14 is upregulated in some cancers alongside glutamine metabolism. Alloferon, a peptide isolated from the insect immune system, exerts anti-viral and anti-inflammatory effects via its immunomodulatory function. In addition, it has anti-tumoral effects, although the underlying mechanisms are largely unknown. Therefore, we investigated the effects of alloferon on the PCa cell lines Panc-1 and AsPC-1. Exposure of these cells to alloferon for 3 weeks led to the downregulation of SLC6A14 expression and decreased glutamine uptake. Given that SLC6A14 plays a role in tumor progression and survival by promoting glutamine uptake into cancer cells, alloferon could be a potential adjuvant for the chemotherapeutic drug gemcitabine.

The effect of alloferon on chemosensitivity of pancreatic cancer through the regulation of SLC6A14 expression

Abstract Pancreatic cancer is one of the most malignant solid tumors with a high mortality rate. Although there have been many trials for effective therapies using chemotherapeutic drugs, such as gemcitabine, pancreatic cancer still shows significantly higher mortality than other types of cancer. Therefore, it is needed to examine the effective therapeutic ways to improve conventional therapy for pancreatic cancer. It has been previously reported that cancer cells possess a high rate of glutamine uptake needed for their rapid proliferation. In addition, it has recently been reported that amino acid transporter SLC6A14 is up-regulated in some cancers in close relation to glutamine metabolism. Alloferon is a peptide isolated from the insect immune system and shows anti-viral and anti-inflammatory effects based on its immune modulating function. In addition, its anti-tumor effect was recently discovered, but the related mechanisms are largely unknown. For this reason, I investigated the effect of alloferon on pancreatic cancer cell lines Panc-1 and AsPC-1. When Panc-1 and AsPC-1 were exposed to alloferon for 3 weeks, I found down-regulation of SLC6A14 expression and decreased glutamine uptake. Given that SLC6A14 is involved in tumor progression and survival by promoting glutamine uptake into cancer cells, alloferon could be an effective way with conventional chemotherapeutic drug, gemcitabine. Therefore, alloferon could be a useful adjuvant for an effective therapeutic way with conventional chemotherapeutic drug, gemcitabine. This study was funded by the NRF of Korea (No.:2017R1A2B2010948, 2017R1A6A3A11032576, 2020R1C1C1009334)