Pancreatic Cancer Cell Lines PANC-1 Research Articles

TAGLN2 targeted control of ARPC5-mediated activation of the MEK/ERK signaling pathway influences the proliferation, invasion, and metastasis of pancreatic cancer cells

PurposePancreatic cancer (PC) is a common tumor of the digestive tract with an insidious onset and high malignancy potential. Currently, surgery is the only effective treatment modality. Therefore, it is crucial to discover new targeted therapeutic modalities. We studied whether transgelin 2 (TAGLN2) targeted control of actin-related protein 2/3 complex subunit 5 (ARPC5)-mediated activation of the MEK/ERK signaling pathway to Influences the proliferation, invasion, and metastasis of pancreatic cancer cells. MethodsThe effects of TAGLN2 overexpression and knockdown on the proliferative viability and invasive metastatic ability of pancreatic cancer cells were verified through in vitro and in vivo assays via constructing a stable lentiviral transfection of human pancreatic cancer cell lines PANC-1 and SW1990. Bioinformatics analysis was used to predict the relationship between TAGLN2 and ARPC5. These findings were subsequently verified through protein profiling, immunofluorescence (IF), and coimmunoprecipitation (CO-IP) assays. In vitro experiments were also conducted to confirm the effect of TAGLN2 modulation on ARPC5 expression, which subsequently affects the proliferation and invasive metastatic ability of pancreatic cancer cells. The study analyzed the relationship between TAGLN2 and the MEK/ERK signaling pathway through bioinformatics and in vitro experiments with the MEK signaling pathway inhibitor U0126. ResultsTAGLN2 is expressed at high levels in pancreatic cancer cell lines, and its expression is positively correlated with poor prognosis of pancreatic cancer. ARPC5 is a direct target of TAGLN2 and is associated with the MEK/ERK signaling pathway. In vivo and ex vivo experiments confirmed that overexpression of TAGLN2 promoted the proliferation, invasion, and metastasis of pancreatic cancer cells, and silencing ARPC5 reversed these effect. ConclusionOur research revealed that TAGLN2 protein binds to ARPC5 protein and contributes to increased ARPC5 expression and activation of the MEK/ERK signaling pathway. This activation promotes pancreatic cancer cell growth, infiltration, and spread. Hence, TAGLN2 is a potential viable therapeutic target in pancreatic cancer and represents a novel therapeutic approach.

Exosomal HSPB1, interacting with FUS protein, suppresses hypoxia-induced ferroptosis in pancreatic cancer by stabilizing Nrf2 mRNA and repressing P450.

Ferroptosis is a new type of programmed cell death, which has been involved in the progression of tumours. However, the regulatory network of ferroptosis in pancreatic cancer is still largely unknown. Here, using datasets from GEO and TCGA, we screened HSPB1, related to the P450 monooxygenase signalling, a fuel of ferroptosis, to be a candidate gene for regulating pancreatic cancer cell ferroptosis. We found that HSPB1 was enriched in the exosomes derived from human pancreatic cancer cell lines SW1990 and Panc-1. Then, hypoxic SW1990 cells were incubated with exosomes alone or together with HSPB1 siRNA (si-HSPB1), and we observed that exosomes promoted cell proliferation and invasion and suppressed ferroptosis, which was reversed by si-HSPB1. Moreover, we found a potential binding affinity between HSPB1 and FUS, verified their protein interaction by using dual-colour fluorescence colocalization and co-IP assays, and demonstrated the promoting effect of FUS on oxidative stress and ferroptosis in hypoxic SW1990 cells. Subsequently, FUS was demonstrated to bind with and stabilize the mRNA of Nrf2, a famous anti-ferroptosis gene that negatively regulates the level of P450. Furthermore, overexpressing FUS and activating the Nrf2/HO-1 pathway (using NK-252) both reversed the inhibitory effect of si-HSPB1 on exosome functions. Finally, our invivo studies showed that exosome administration promote tumour growth in nude mice of xenotransplantation, which was able to be eliminated by knockdown of HSPB1. In conclusion, exosomal HSPB1 interacts with the RNA binding protein FUS and decreases FUS-mediated stability of Nrf2 mRNA, thus suppressing hypoxia-induced ferroptosis in pancreatic cancer.

Evaluation of Helium Ion Radiotherapy in Combination with Gemcitabine in Pancreatic Cancer In Vitro.

Pancreatic cancer is one of the most aggressive and lethal cancers. New treatment strategies are highly warranted. Particle radiotherapy could offer a way to overcome the radioresistant nature of pancreatic cancer because of its biological and physical characteristics. Within particles, helium ions represent an attractive therapy option to achieve the highest possible conformity while at the same time protecting the surrounding normal tissue. The aim of this study was to evaluate the cytotoxic efficacy of helium ion irradiation in pancreatic cancer in vitro. Human pancreatic cancer cell lines AsPC-1, BxPC-3 and Panc-1 were irradiated with photons and helium ions at various doses and treated with gemcitabine. Photon irradiation was performed with a biological cabin X-ray irradiator, and helium ion irradiation was performed with a spread-out Bragg peak using the raster scanning technique at the Heidelberg Ion Beam Therapy Center (HIT). The cytotoxic effect on pancreatic cancer cells was measured with clonogenic survival. The survival curves were compared to the predicted curves that were calculated via the modified microdosimetric kinetic model (mMKM). The experimental relative biological effectiveness (RBE) of helium ion irradiation ranged from 1.0 to 1.7. The predicted survival curves obtained via mMKM calculations matched the experimental survival curves. Mainly additive cytotoxic effects were observed for the cell lines AsPC-1, BxPC-3 and Panc-1. Our results demonstrate the cytotoxic efficacy of helium ion radiotherapy in pancreatic cancer in vitro as well as the capability of mMKM calculation and its value for biological plan optimization in helium ion therapy for pancreatic cancer. A combined treatment of helium irradiation and chemotherapy with gemcitabine leads to mainly additive cytotoxic effects in pancreatic cancer cell lines. The data generated in this study may serve as the radiobiological basis for future experimental and clinical works using helium ion radiotherapy in pancreatic cancer treatment.

Calix[6]arene dismantles extracellular vesicle biogenesis and metalloproteinases that support pancreatic cancer hallmarks

Many challenges are faced in pancreatic cancer treatment due to late diagnosis and poor prognosis because of high recurrence and metastasis. Extracellular vesicles (EVs) and matrix metalloproteinases (MMPs), besides acting in intercellular communication, are key players in the cancer cell plasticity responsible for initiating metastasis. Therefore, these entities provide valuable targets for the development of better treatments. In this context, this study aimed to evaluate the potential of calix[6]arene to disturb the release of EVs and the activity of MMPs in pancreatic cancer cells. We found a correlation between the endocytic-associated mediators and the prognosis of pancreatic cancer patients. We observed a more active EV machinery in the pancreatic cancer cell line PANC-1, which was reduced three-fold by treatment with calix[6]arene at subtoxic concentration (5 μM; p 〈0,001). We observed the modulation of 186 microRNAs (164 miRNAs upregulated and 22 miRNAs downregulated) upon calix[6]arene treatment. Interestingly, some of them as miR-4443 and miR-3909, regulates genes HIF1A e KIF13A that are well known to play a role in transport of vesicles. Furthermore, Calix[6]arene downmodulated matrix metalloproteinases (MMPs) -2 and − 9 and disturbed the viability of pancreatic organoids which recapitulate the cellular heterogeneity, structure, and functions of primary tissues. Our findings shed new insights on calix[6]arene's antitumor mechanism, including its intracellular effects on vesicle production and trafficking, as well as MMP activity, which may harm the tumor microenvironment and contribute to a reduction in cancer cell dissemination, which is one of the challenges associated with high mortality in pancreatic cancer.

Synchrotron radiation-FTIR biomolecular assessment in PANC-1 and MIA PaCa-2 pancreatic cancer cells after treatment with Gd-TiO2 nanoparticles

The increasing incidence rate of pancreatic cancer worldwide, along with high resistance to existing chemotherapies and radiotherapy, demand new approaches for its treatment. Nanoparticle-guided cancer treatment modalities are promising in their anti-cancer efficiency and upgrading potential. We have synthesized and characterized Gd-doped titanium-dioxide nanoparticles (Gd-TiO2 NPs), which showed good biocompatibility with MIA PaCa-2 and PANC-1 pancreatic cancer cell lines. To assess the effect that these NPs have on tumor cells, we used synchrotron radiation Fourier transform infrared spectroscopy and principal component analysis. We elucidated the biochemical changes in the two cell lines induced after their interaction with these NPs. Results demonstrated changes in nucleic acids and carbohydrate metabolism and alterations in the protein conformation in both cell lines. In addition, considerable changes in lipid area were observed in PANC-1 cell line, suggesting that Gd-TiO2 NPs have a prospective to be further studied as systems for pancreatic cancer treatment.

Abstract 7291: Detection of a truncated form of multidrug resistance protein 1 (MRP1) in plasma sEVs derived from cancer patients

Abstract Multidrug resistance protein 1 (MRP1/ABCC1) is an ATP dependent transmembrane efflux pump that confers to drug resistance. Overexpression of MRP1 has been observed in both pancreatic ductal adenocarcinoma (PDAC) and breast cancer tissues. Numerous proteomics studies have revealed the presence of MRP1 in small extracellular vesicles (sEVs) released from cancer cells. Cancer-derived sEVs are known to be released into the circulation, thus becoming attractive candidates for non-invasive biomarker development. However, whether the MRP1 level in plasma sEVs is indicative of human cancer has not been evaluated. This study examined the MRP1 expression in plasma sEVs derived from patients with PDAC, breast and colon cancer, and age- and gender-matched healthy subjects. The patient plasma samples were obtained primarily from the NCI-sponsored Cooperative Human Tissue Network and Stephenson Cancer Center. Healthy plasma samples were provided by the Oklahoma Blood institute. Human pancreatic cancer cell lines PANC-1, MIA PaCa-2 and BxPC-3, and the pancreatic ductal cell line hTERT-HPNE were tested for MRP1 expression prior to examination of plasma samples. Cellular and plasma sEVs were isolated using the double filtration followed by polymer precipitation method. Western blot was performed to assess the expression level of MRP1 and proteomics was applied to confirm the detection of a truncated form of MRP1 in plasma sEVs. MRP1 expression was detected in the sEVs derived from all three pancreatic cancer cell lines but absent in the sEVs from the HPNE line. Overexpression of a truncated MRP1 protein was detected in plasma sEVs derived from patients with early stage (stage I-IIA) and late stage (III-IV) PDAC, compared with that from matched healthy subjects (n=17 for each group). Similar findings were evident in plasma sEVs from patients with breast cancer (n=7), while the results remained inconclusive in plasma sEVs from patients with colon cancer (n=7). Protein structure analysis indicated that the truncated form of MRP1 likely consists of the regions between the QCRL-1 motif and the C-terminus of the protein. Proteomic analysis detected the peptides derived from the C-terminus region, consistent with the structural analysis. Furthermore, the truncated form of MRP1 can only be detected using antibodies against the epitopes in the C-terminus and QCRL-1 region of MRP1 protein. In summary, we have detected a truncated form of MRP1 protein in plasma sEVs derived from cancer patients, and the level of its expression is significantly elevated in patients with PDAC and breast cancer. Citation Format: Kritisha Bhandari, Jeng Shi Kong, Chao Xu, Ajay Jain, Wei-Qun Ding. Detection of a truncated form of multidrug resistance protein 1 (MRP1) in plasma sEVs derived from cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7291.

Abstract 5904: Targeting NaV1.7 channels in pancreatic cancer: Implications for EF2K and P-Src/P-Fak/integrin β1 signaling pathways

Abstract Pancreatic cancer (PaCa) ranks as the fourth leading cause of cancer-related deaths in the United States and is among the top five worldwide. Its hallmark characteristics include early invasion, metastasis, resistance to chemotherapy and radiotherapy, and aggressive tumor progression. Evaluating new generation treatments with significant potential in this ongoing battle against cancer is crucial. Voltage-gated sodium channels (VGSC), long detected in various metastatic cell lines and tissue samples beyond breast, lung, and prostate cancer, are of particular interest. This study aimed to explore the therapeutic effects of inhibiting NaV1.7 and its neonatal variant, nNaV1.7, in pancreatic cancer cells. The study utilized human normal keratinocyte cell line HaCaT and pancreatic cancer cell lines PANC-1 and MiaPaCa-2. It investigated the roles and effects of adult and neonatal isoforms of the NaV1.7 channel in pancreatic cancer proliferation, invasion, and metastasis. The findings revealed significantly higher adult and neonatal NaV1.7 mRNA expressions in PANC-1 and MiaPaCa-2 cell lines compared to HaCaT cells. Specific siRNAs effectively downregulated channel mRNA and protein expressions. Notably, NaV1.7 siRNA treatments significantly inhibited cell proliferation and colony-forming capacity in PANC-1 and MiaPaCa-2 cells, without cytotoxic effects on HaCaT cells. Combining gemcitabine with specific NaV1.7 siRNAs enhanced drug efficacy in the PANC-1 cell line. Furthermore, NaV1.7 siRNAs significantly reduced cell invasion, migration, and wound healing in both cell lines. These siRNAs also induced apoptosis and G1 arrest in the cell cycle. They inhibited protein expressions involved in key signaling pathways, including P-Src/P-Fak/Integrin β1, EF2K, P-Akt, P-mTOR, PARP, Caspase-3/9, Cyclin D1/E1. This study is pioneering, as literature lacks research on the expression and function of NaV1.7 and nNaV1.7 in pancreatic cancer cells or tissue samples. In conclusion, NaV1.7 channel isoforms play a significant role in the development, progression, and metastasis of pancreatic cancer and present as a potential therapeutic target in PaCa. Citation Format: Mumin Alper Erdogan, Ayse Caner. Targeting NaV1.7 channels in pancreatic cancer: Implications for EF2K and P-Src/P-Fak/integrin β1 signaling pathways [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5904.

Abstract 6001: Repurposing dihydroergotamine mesylate as a potential MCL-1 inhibitor and its antitumor effect in pancreatic cancer cells

Abstract Background: Myeloid cell leukemia 1 (MCL-1) is an anti-apoptotic member of the BCL-2 protein family which is involved in intrinsic (mitochondrial) pathway of apoptosis and is deregulated in several cancers. Current MCL-1 specific inhibitors have limitations in terms of efficiency, tolerability, and off-target effects and challenges associated with shallow binding groove of MCL-1. In this study, dihydroergotamine mesylate (DHE), an approved anti-migraine drug, was found as a potential ligand of the MCL-1 BH3-binding pocket and was further evaluated for its potential MCL-1 inhibition and effect on pancreatic cancer cells. Methods: PubChem Database was used for library preparation and virtual screening (OpenBabel and AutoDock Vina). The 55 crystal structures available for MCL-1 in Protein Data Bank (PDB) were clustered using principal component analysis with Bio3D R-package to select representative PDBs for further screening. Consensus voting and k-means clustering was used to shortlist compounds for Molecular dynamics (MD) simulations. MD simulations (100 nanoseconds) by GROMACS were employed to measure stability of ligands in MCL-1 binding pocket. DHE efficacy on cell proliferation was evaluated with MTS and clonogenic assays and on apoptosis using the FITC/Annexin V flow cytometry assay in MiaPaCa-2 and PANC-1 pancreatic cancer cell lines. Effect of DHE treatment on MCL-1 gene and protein expression was analyzed using qRT-PCR and western blotting, respectively. Results: Computational screening identified DHE (PubChem ID: 12308974) as a top hit exhibiting consistent interactions within the MCL-1 BH3-binding pocket. Notably, DHE displayed stable RMSD and formed four hydrogen bonds throughout MD simulations. In vitro results showed that DHE significantly reduced viability of MiaPaCa-2 and PANC-1 pancreatic cancer cells with IC50 values of 31 μM and 47 μM, respectively. DHE significantly (P<0.001) suppressed colony formation by pancreatic cancer cells in a dose-dependent (10μM, 20μM, and 40μM) manner. The percentage of Annexin V-positive and Propidium iodide-negative fraction in MiaPaCa-2 cells treated with DHE also increased in a dose-dependent manner. DHE did not have significant effect on MCL-1 mRNA expression. However, western blotting demonstrated MCL-1 protein levels were significantly reduced in both pancreatic cancer cell lines upon DHE treatment. Conclusion: Our findings showed DHE suppresses the pancreatic cancer cells viability and proliferation, and significantly increased early apoptotic cells. DHE treatment had no effect on MCL-1 at the transcription level but significantly reduced the protein, suggesting posttranslational modifications, and thus future mechanism of action studies is required. The present study reports that the anti-migraine drug DHE might be a novel therapeutic agent for pancreatic cancer and needs to be explored further. Citation Format: Pooja Mittal, Jae Ho Lo, Shivani Soni, Francesca Battaglin, Shradheya RR Gupta, Lesly Torres-Gonzalez, Yan Yang, Sandra Algaze, Priya Jayachandran, Karam Ashouri, Alexandra Wong, Wu Zhang, Jian Yu, Lin Zhang, Joshua Millstein, Indrakant Kumar Singh, Heinz Josef Lenz. Repurposing dihydroergotamine mesylate as a potential MCL-1 inhibitor and its antitumor effect in pancreatic cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6001.

Gluing GAP to RAS Mutants: A New Approach to an Old Problem in Cancer Drug Development.

Mutated genes may lead to cancer development in numerous tissues. While more than 600 cancer-causing genes are known today, some of the most widespread mutations are connected to the RAS gene; RAS mutations are found in approximately 25% of all human tumors. Specifically, KRAS mutations are involved in the three most lethal cancers in the U.S., namely pancreatic ductal adenocarcinoma, colorectal adenocarcinoma, and lung adenocarcinoma. These cancers are among the most difficult to treat, and they are frequently excluded from chemotherapeutic attacks as hopeless cases. The mutated KRAS proteins have specific three-dimensional conformations, which perturb functional interaction with the GAP protein on the GAP-RAS complex surface, leading to a signaling cascade and uncontrolled cell growth. Here, we describe a gluing docking method for finding small molecules that bind to both the GAP and the mutated KRAS molecules. These small molecules glue together the GAP and the mutated KRAS molecules and may serve as new cancer drugs for the most lethal, most difficult-to-treat, carcinomas. As a proof of concept, we identify two new, drug-like small molecules with the new method; these compounds specifically inhibit the growth of the PANC-1 cell line with KRAS mutation G12D in vitro and in vivo. Importantly, the two new compounds show significantly lower IC50 and higher specificity against the G12D KRAS mutant human pancreatic cancer cell line PANC-1, as compared to the recently described selective G12D KRAS inhibitor MRTX-1133.

In vitro simulation of the liver first-pass effect with biotransformation-competent HepG2 cells to study effects of MG-132 on liver and cancer cells.

Liver biotransformation is the major route for drug metabolism in humans, often catalysed by cytochrome P450 (CYP) enzymes. This first-pass effect can lead to hepatotoxicity and influences the bioavailability of drugs. We aimed to establish in vitro culture systems simulating the liver first-pass to study effects of the proteasome inhibitor MG-132 simultaneously on hepatocytes and cancer cells. The first-pass effect was simulated by conditioned medium transfer (CMT) from pre-treated HepG2 CYP3A4-overexpressing cells to either pancreatic cancer cell line PANC-1 or primary colon cancer cells, and by indirect co-culture (CC) of liver and cancer cells in a shared medium compartment. Experimental proteasome inhibitor MG-132 was used as test substance as it is detoxified by CYP3A4. Cancer cells showed higher viabilities in the first-pass simulation by CMT and CC formats when compared to monocultures indicating effective detoxification of MG-132 by HepG2 CYP3A4-overexpressing cells. HepG2-CYP3A4 cells showed reduced viabilites after treatment with MG-132. We successfully established two different culture systems to simulate the liver first-pass effect in vitro. Such systems easily allow to study drug effects simultaneously on liver and on target cancer cells. They are of great value in pre-clinical cancer research, pharmaceutical research and drug development.

Effect of NFATc2- and Sp1-mediated TNFalpha Regulation on the Proliferation and Migration Behavior of Pancreatic Cancer Cells.

One in two people will develop a tumor during their lifetime. Adenocarcinoma of the pancreas is one of the most aggressive types of cancer in humans with very poor long-term survival. A central role in the carcinogenesis of pancreatic cancer has been attributed to NFAT transcription factors. Previous studies have identified the transcription factor Sp1 as a binding partner of NFATc2 in pancreatic cancer. Using expression profile analysis, our group was able to identify the tumor necrosis factor TNFalpha as a target gene of the interaction between NFATc2 and Sp1. The present study investigated the effect of TNFalpha over-expression via the transcription factors NFATc2 and Sp1 on the pancreatic cancer cell lines PaTu 8988t and PANC-1. Transient transfection of NFATc2, Sp1, and TNFalpha siRNAs and their effects on the expression were investigated with immunoblot. Cell proliferation was measured with the ELISA BrdU assay. Cell migration was assayed with a Cell Migration Assay Kit using a Boyden chamber. Inhibition of the transfection factors NFATc2, Sp1, or TNFalpha by siRNA significantly inhibited proliferation, which was exacerbated when using the combination of NFATc2 and Sp1. TNFalpha was able to counterbalance this effect. In contrast to proliferation, migration of pancreatic cancer cells was increased by inhibiting these transfection factors. Tumor progression is strongly influenced by transcriptional changes in signaling cascades and oncogene mutations as well as by changes in tumor suppressor genes. Further studies are needed to understand the underlying mechanisms of these processes.

Differential Sensitivity to Ionizing Radiation in Gemcitabine-Resistant and Paclitaxel-Resistant Pancreatic Cancer Cells

IntroductionChemoresistance remains a major challenge in treating pancreatic ductal adenocarcinoma (PDAC). While chemoradiation has proven effective in other tumor types, such as head-and-neck squamous cell carcinoma, its role in PDAC and its impact on acquired chemoresistance have yet to be fully explored. In this study, we investigated the sensitivity of gemcitabine- and paclitaxel-resistant PDAC cells to ionizing radiation (IR) and their underlying mechanisms. Materials and MethodsGemcitabine-resistant (GR) and paclitaxel-resistant (PR) clones were generated from PANC-1, PATU-T and SUIT2-007 pancreatic cancer cell lines. Cell survival after radiation was assessed using clonogenic assay, SRB assay, apoptosis and spheroid growth by bioluminescence while radiation-induced DNA damage was evaluated with Western blot, XL-PCR, ROS production and immunofluorescence. Autophagy and modulation of Hippo pathway were investigated using proteomics, Western blot, immunofluorescence and RT-qPCR. ResultsIn both 2D and 3D settings, PR cells were more sensitive to IR and showed decreased β-globin amplification indicating more DNA damage accumulation as compared to GR or wild-type (WT) cells after 24 hours. Proteomics analysis of PATU-T PR revealed that the protein MST4, a kinase involved in autophagy and Hippo signaling pathway, was highly downregulated. Differential association was found between autophagy and radiation treatment depending on the cell model. Interestingly, increased YAP nuclear localization and downstream Hippo pathway target gene expression were observed in in SUIT2-007 PR cells in response to IR, as compared to WT and GR. ConclusionThis is the first study investigating the potential of IR in targeting PDAC cells with acquired chemoresistance. Our results demonstrate that PR cells exhibit enhanced sensitivity to IR due to greater accumulation of DNA damage. Additionally, depending on the specific cellular context, radiation-induced modulation of autophagy and the Hippo pathway emerged as potential underlying mechanisms, and these findings have the potential to inform personalized treatment strategies for patients with acquired chemoresistance.

Alteration in the expression of the chemotherapy resistance‑related genes in response to chronic and acute hypoxia in pancreatic cancer.

Pancreatic cancer is currently one of the least curable types of human cancer and remains a key health problem. One of the most important characteristics of pancreatic cancer is its ability to grow under hypoxic conditions. Hypoxia is associated with resistance of cancer cells to radiotherapy and chemotherapy. It is a major contributor to pancreatic cancer genetic instability, which local and systemic resistance that may result in poor clinical outcome. Accordingly, identifying gene expression changes in cancer resistance genes that occur under hypoxic conditions may identify a new therapeutic target. The aim of the present study was to explore the association between hypoxia and resistance to chemotherapy and determine the alteration in the expression of cancer resistance-related genes in the presence of hypoxia. Pancreatic cancer cells (PANC-1) were exposed to 8 h hypoxic episodes (<1% oxygen) three times/week for a total of 20 episodes (chronic hypoxia) or 72 h hypoxic episodes twice/week for a total of 10 episodes (acute hypoxia). The alterations in gene expression were examined using reverse transcription-quantitative PCR array compared with normoxic cells. Chemoresistance of hypoxic cells toward doxorubicin was assessed using MTT cell proliferation assay. Both chronic and acute hypoxia induced chemoresistance toward doxorubicin in PANC-1 pancreatic cancer cell line. The greatest changes occurred in estrogen Receptor Alpha Gene (ESR1) and ETS Like-1 protein (ELK1) pathways, in nucleic transcription factor Peroxisome proliferator-activated receptors (PPARs) and in a cell cycle inhibitor cyclin dependent kinase inhibitor 1A (CDKN1A). The present study demonstrated that exposing cells to prolonged hypoxia results in different gene expression changes involving pleotropic pathways that serve a role in inducing resistance in pancreatic cancer.

Juglone Effects by Dual Way on mTOR Gene Expression, Which Plays Central Role in Cell Growth, Survival and Metabolism, in PANC-1 and BxPC-3 Pancreatic Cancer Cell Lines

Background/Aims: Juglone, as a naphthoquinone, has been shown to have cytotoxic and apoptotic effects in various cancer cells and besides this effects it was reported to have anti-invasive and anti-metastatic effects in PANC-1 and BxPC-3 cells in our previous studies. In this study, we investigated the effects of juglone on GRP75, TFAM and mTOR genes encoding key proteins associated with mitochondrial biogenesis and activation in PANC-1 and BxPC-3 pancreatic cancer cells since mitochondria has central roles in cancer cell survival, metastasis and therapeutic resistance. Methods: In our study; 5, 10, 15 and 20 μM juglone doses were selected as the application doses considering the IC50 value determined after MTT test results and the expressions of the target genes were analyzed by qPCR method after application of juglone doses for 24 hours. Results: Our study results revealed that juglone had an opposite and strong effects on mTOR expression in both cell lines. Conclusion: Our findings suggest that juglone has a developable potential and is a promising theurapeutic agent to develop new strategies for the battle with cancer with those effects on mTOR gene which plays a central role in cellular homeostasis and several cellular events including cell growth, survival and metabolism.

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.