oxadiazoles and Pancreatic-Neoplasms

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal form of cancer characterized by drug resistance, urging new therapeutic strategies. In recent years, protein kinases have emerged as promising pharmacological targets for the treatment of several solid and hematological tumors. Interestingly, cyclin-dependent kinase 1 (CDK1) is overexpressed in PDAC tissues and has been correlated to the aggressive nature of these tumors because of its key role in cell cycle progression and resistance to the induction of apoptosis. For these reasons, CDK1 is one of the main causes of chemoresistance, representing a promising pharmacological target. In this study, we report the synthesis of new 1,2,4-oxadiazole compounds and evaluate their ability to inhibit the cell growth of PATU-T, Hs766T, and HPAF-II cell lines and a primary PDAC cell culture (PDAC3). Compound

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Pancreatic Ductal; Catalytic Domain; CDC2 Protein Kinase; Cell Line, Tumor; Cell Proliferation; Drug Screening Assays, Antitumor; Humans; Imidazoles; Indoles; Molecular Docking Simulation; Oxadiazoles; Pancreatic Neoplasms; Protein Binding; Protein Kinase Inhibitors; Signal Transduction; Structure-Activity Relationship

Pancreatic cancer remains one of the most lethal diseases with dismal five-year survival rates. Although mutant KRas protein-driven activation of downstream MAPK Raf/MEK/ERK and PI3K/Akt signaling pathways represent major oncogenic alterations, signaling blockade with MEK and PI3K inhibitors has shown that intrinsic resistance may hamper the effectiveness of this targeted approach. However, there have been no mass spectrometry-based proteomic studies for in-depth comparison of protein expression differences between pancreatic cancer cells with sensitivity and resistance to MEK and PI3K kinase inhibitors. In this work, we compared PANC-1 and MIA PaCa-2 pancreatic cancer cells which are, respectively, resistant and sensitive to MEK- and PI3K-targeted therapy. We conducted a label-free data-independent acquisition mass spectrometry (SWATH-MS) study with extensive peptide fractionation to quantitate 4808 proteins and analyze differential expression of 743 proteins between resistant and sensitive cells. This allowed identification of the tumor suppressor protein phosphatase 2A (PP2A) and proteins from mitochondrial respiratory complex I implicated in oxidative phosphorylation as alternative candidate drug targets for cells resistant to MEK and PI3K inhibition. PP2A activator DT-061 decreased viability of PANC-1 cells and this was accompanied by reduced expression of c-Myc. PANC-1 cells also showed response to metformin and the novel complex I inhibitor IACS-010759. These findings provide insights into the distinct cellular proteomes and point out alternative pharmacological targets for MEK and PI3K inhibition-resistant pancreatic cancer cells.

Topics: Cell Line, Tumor; Cell Survival; Drug Resistance, Neoplasm; Humans; Indazoles; Mass Spectrometry; Mitogen-Activated Protein Kinase Kinases; Oxadiazoles; Pancreatic Neoplasms; Phosphatidylinositol 3-Kinases; Phosphoinositide-3 Kinase Inhibitors; Phosphorylation; Piperidines; Protein Kinase Inhibitors; Proteome; Proteomics; Signal Transduction; Sulfonamides

To continue the quest of newer anticancer agents, herein a novel class of 1,4-Dihydroindenopyrazole linked oxadiazole conjugates 9(a-r) was designed, synthesized and experimented for their anti-proliferative activities against four different cancer cell lines (human) such as MDA MB-231 (breast), PANC-1 (pancreatic), MCF-7 (breast), and Caco-2 (Colorectal) by using MTT assay. Among the series compound 9h and 9 m demonstrated significant potency against the PANC-1 (human pancreatic cancer cells) with IC

Topics: Antineoplastic Agents; Apoptosis; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Dose-Response Relationship, Drug; Drug Design; Drug Screening Assays, Antitumor; Humans; Molecular Docking Simulation; Molecular Structure; Oxadiazoles; Pancreatic Neoplasms; Pyrazoles; Quantitative Structure-Activity Relationship

New indole-tethered [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one (8a-j) and [1,3,4]oxadiazolo[3,2-a]pyrimidin-5-one hybrids (9a-e) were synthesized using [4+2] cycloaddition reactions of functionalized 1,3-diazabuta-1,3-dienes with indole-ketenes. All molecular hybrids were structurally characterized by spectroscopic techniques (IR, NMR, and HRMS) and screened for their anti-pancreatic cancer activity in vitro. The [1,3,4]oxadiazolo[3,2-a]pyrimidin-5-one hybrids (9a-e) showed stronger anti-pancreatic cancer activity than the [1,3,4]thiadiazolo[3,2-a]pyrimidin-5-one hybrids (8a-j) against the PANC-1 cell line. Compound 9d bearing an ortho-chlorophenyl moiety emerged as the most potent anti-pancreatic cancer agent with an IC

Topics: Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Cell Survival; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Indoles; Molecular Structure; Oxadiazoles; Pancreatic Neoplasms; Pyrimidines; Structure-Activity Relationship; Thiadiazoles

Recently, clinical studies using anti-immune checkpoint molecule antibodies have been successful in solid tumors, such as melanoma and non-small cell lung cancers. However, pancreatic cancers are still intractable and difficult to treat once recurrence or metastasis occurs; thus, novel combined use of immune checkpoint blockade (ICB) with molecular targeted drugs is considered a therapeutic option. Previously, we developed a novel humanized MHC-double knockout (dKO) NOG mouse model and demonstrated that an anti-PD-1 antibody or a STAT3 inhibitor showed anti-tumor effects through an immunological mechanism. In the current study, using a humanized mouse model, we aimed to develop a combination therapy with an anti-PD-1 antibody and a STAT3 inhibitor (STX-0119) for use in vivo against pancreatic cancer. In an in vitro investigation, STX-0119 showed weak to moderate cytotoxic activity against several pancreatic cancer cell lines, which exhibited activated pSTAT3 and weak PD-L1 expression. However, unexpectedly, an in vivo study indicated that the combination of the anti-PD-1 antibody with STX-0119 remarkably reduced the anti-tumor effect and TIL numbers despite the effective anti-tumor activity against pancreatic cancer was produced individually by STX-0119 and the anti-PD-1 antibody. These results suggested that the combination of an anti-PD-1 antibody with specific signal inhibiting drugs should be carefully evaluated to avoid unexpected side effects, and such studies might contribute to the development of an effective combination regimen of ICB with cancer-targeting drugs such as tyrosine kinase inhibitors (TKIs).

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Cell Line, Tumor; Drug Interactions; Genes, MHC Class I; Genes, MHC Class II; Humans; Leukocytes, Mononuclear; Lymphocytes, Tumor-Infiltrating; Mice; Mice, Knockout; Oxadiazoles; Pancreatic Neoplasms; Programmed Cell Death 1 Receptor; Quinolines; Signal Transduction; STAT3 Transcription Factor; Transplantation Chimera; Treatment Outcome; Xenograft Model Antitumor Assays

An expanded set of diversely substituted 1,2,4-oxadiazole-containing primary aromatic sulfonamides was synthesized and tested for inhibition of human carbonic anhydrase I, II, IX and XII isoforms. The initial biochemical profiling revealed a significantly more potent inhibition of cancer-related, membrane-bound isoform hCA IX (reaching into submicromolar range), on top of potent inhibition of hCA XII that is another cancer target. The observed structure-activity relationships have been rationalized by molecular modeling. Comparative single-concentration profiling of the carbonic anhydrase inhibitors synthesized for antiproliferative effects against normal (ARPE-19) and cancer (PANC-1) cell lines under chemically induced hypoxia conditions revealed several candidate compounds selectively targeting cancer cells. More in-depth characterization of these leads revealed two structurally related compounds that showed promising selective cytotoxicity against pancreatic cancer (PANC-1) and melanoma (SK-MEL-2) cell lines.

Topics: Carbonic Anhydrase Inhibitors; Carbonic Anhydrase IX; Carbonic Anhydrases; Cell Line; Cell Line, Tumor; Cell Proliferation; Drug Discovery; Humans; Hypoxia; Melanoma; Neoplasms; Oxadiazoles; Pancreatic Neoplasms; Structure-Activity Relationship; Sulfonamides

The aim of the present study was to investigate the possible interaction between intracellular Ca(2+) and nitric oxide (NO) in rat pancreatic acinar cells, especially intracellular signaling events. (1) Nitric oxide donors SNP (0.1-100 μM) and NOR-3 (50-400 μM) induced Ca(2+) oscillations in fluo-4-loaded acini, that appeared to be analogous to what we usually observe in acini stimulated with physiological secretagogues such as CCK-8 and this oscillations were abolished in the presence of carboxy-PTIO. (2) The NO donors-evoked Ca(2+) oscillations were not abolished even in the absence of extracellular Ca(2+) but totally disappeared when cells were pretreated with thapsigargin, a sarcoplasmic-endoplasmic reticulum Ca(2+) ATPase (SERCA) inhibitor. (3) Inhibition of guanylate cyclase with 1 H-[1,2,4] oxadiazolo [4,3-a] quinoxaline-1-one (ODQ) attenuated Ca(2+) oscillations evoked by SNP in the absence of extracellular Ca(2+). (4) Inhibitors of phospholipase C activity, U73122 and the IP(3)R blocker xestospongin C, both abolished the SNP-induced Ca(2+) response. (5) Furthermore, we found that both CCK-8 and carbachol (CCh) induced NO production in DAF-2-loaded acinar cells and that an inhibitor of NO synthase, N(G)-monomethyl-l-arginine (L-NMMA), significantly reduced CCK-8-induced Ca(2+) oscillation. These results indicate that NO mobilizes Ca(2+) from internal stores through activation of guanylate cyclase and resultant cGMP production. In addition, PLC activation of IP(3) production is also suggested to be involved in Ca(2+) mobilization via IP(3) receptors. This suggests the presence of cross-talk between Ca(2+) and NO in pancreatic acini and this cascade may, at least partially, participate in physiological secretagogue-evoked Ca(2+) dynamics in pancreatic acinar cells.

Topics: Animals; Calcium; Carcinoma, Acinar Cell; Estrenes; Inositol 1,4,5-Trisphosphate; Macrocyclic Compounds; Male; Nitric Oxide; Nitric Oxide Donors; Nitroprusside; Oxadiazoles; Oxazoles; Pancreatic Neoplasms; Phosphodiesterase Inhibitors; Pyrrolidinones; Quinoxalines; Rats; Rats, Wistar; Signal Transduction; Sincalide; Type C Phospholipases

A series of new indole-based 3,5-disubstituted 1,2,4-oxadiazoles has been designed and synthesised as potential pro-apoptotic antitumour agents, via the base-catalysed condensation reaction between substituted amidoximes and indole esters. Evaluation of antiproliferative activity against the human cancer cell lines COLO 320 (colorectal) and MIA PACA-2 (pancreatic) revealed IC(50) values in the low micromolar range. Selected compounds were able to trigger apoptosis in sensitive cell lines, for example via activation of caspase-3/7, demonstrating that indole-based oxadiazoles possess in vitro antitumour and pro-apoptotic activity.

Topics: Antineoplastic Agents; Apoptosis; Cell Line; Cell Line, Tumor; Cell Survival; Colorectal Neoplasms; Drug Design; Humans; Indoles; Myocytes, Cardiac; Oxadiazoles; Pancreatic Neoplasms; Structure-Activity Relationship

Biological thiols and disulfides in rat and hamster tissues were simultaneously determined by HPLC-fluorescence detection using 4-(aminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (ABD-F) and ammonium 7-fluoro-2,1,3-benzoxadiazole-4-sulfonate (SBD-F). The coefficients of variation (CV) of the method for reduced glutathione (GSH) and oxidized glutathione (GSSG) in liver and for cysteine (CySH) and cystine (CySSCy) in kidney were less than 3.1%. In 11 tissues of Wistar rats (liver, spleen, heart, lung, stomach, bladder, ovary, uterus, adrenal, kidney and pancreas), only CySH, CySSCy, GSH and/or GSSG were detected. Other thiols and disulfides were at extremely low levels in all samples. Both concentrations of CySH and CySSCy in the livers of old rats (111 weeks old, F344) were significantly higher than those of young rats (8 weeks old) (CySH, 0.246 +/- 0.099 vs 0.130 +/- 0.020 mumol/g; CySSCy, 0.051 +/- 0.027 vs 0.013 +/- 0.002 mumol/g). Administration of N-nitrosobis(2-oxopropyl)amine (BOP), a selective carcinogen of hamster pancreatic cancer, to Syrian golden hamsters (38 weeks old) resulted in the increase in the pancreas of GSH to a level 19 times as high and of GSSG to a level 14 times as high as those in untreated hamsters (GSH, 1.173 +/- 0.272 vs 0.062 +/- 0.017 mumol/g; GSSG, 0.155 +/- 0.063 vs 0.011 +/- 0.001 mumol/g).

Topics: Animals; Chemical Phenomena; Chemistry; Chromatography, High Pressure Liquid; Cricetinae; Disulfides; Female; Fluorobenzenes; Indicators and Reagents; Mesocricetus; Nitrosamines; Oxadiazoles; Pancreas; Pancreatic Neoplasms; Rats; Rats, Inbred F344; Rats, Inbred Strains; Spectrometry, Fluorescence; Spectrophotometry, Ultraviolet; Sulfhydryl Compounds; Tissue Distribution

Carcinogenicity of eight 5-nitrofurans with heterocyclic substituents at the 2-position of the furan ring was investigated by feeding the chemicals to Sprague-Dawley female rats. N-[5-(5-nitro-2-furyl)-1,3,4-thiadiazol-2-yl]acetamide induced in 30 rats the highest incidence of tumors with the greatest number of tissues involved: forestomach squamous cell tumors (22), kidney pelvis transitional cell carcinomas (15), pulmonary alveolar cell carcinomas (16), hemangioendothelialsarcomas (20) of the intestine, mesentery, liver, lung, and pancreas, and a few tumors of other tissues. 2-Amino-5-(5-nitro-2-furyl)-1,3,4-thiadiazole, 2-amino-5-(5-nitro-2furyl)-1,3,4-oxadiazole, and trans-2-[dimethylamino)methylimino]-5-[2-(5-nitro-2-furyl)vinyl]-1,3,4-oxadiazole produced high incidences of mammary tumors. The other four 5-nitrofurans tested: N-[4-(5-NITRO-2-FURYL)-2-THIAZOLYL]ACETAMIDE;2,3,4-TRIFLUORO-N-[4-(5-NITRO-2-furyl)-2-thiazoly]acetamide;5-(5-nitro-2-furyl)-1,3,4-oxadiazol-2-ol; and N-( [3-(5-nitro-2-furyl)-1,2,4-oxadiazol-5-yl]methyl)acetamide were associated with tumor incidences of 40-60%. Two other chemicals were also tested: 2-Amino-5-nitrothiazole caused a low incidence of breast and kidney pelvis tumors, and 2-amino-4-(p-nitrophenyl)thiazole induced a high incidence of breast and salivary gland adenocarcinomas and lymphomas.

Topics: Adenocarcinoma; Adenocarcinoma, Bronchiolo-Alveolar; Administration, Oral; Amines; Animals; Carcinogens; Carcinoma, Squamous Cell; Carcinoma, Transitional Cell; Female; Hemangiosarcoma; Intestinal Neoplasms; Kidney Neoplasms; Liver Neoplasms; Lung Neoplasms; Lymphoma; Mammary Neoplasms, Experimental; Mesentery; Neoplasms, Experimental; Nitrofurans; Oxadiazoles; Pancreatic Neoplasms; Rats; Salivary Gland Neoplasms; Stomach Neoplasms; Thiadiazoles