Colorectal cancer (CRC) remains a significant global health burden, emphasizing the need for innovative treatment strategies. 95% of the CRC population are microsatellite stable (MSS), insensitive to classical immunotherapies such as anti-PD-1; on the other hand, responders can become resistant and relapse. Recently, the use of cancer vaccines enhanced the immune response against tumor cells.
View Article and Find Full Text PDFYAP and TAZ, the Hippo pathway terminal transcriptional activators, are frequently upregulated in cancers. In tumor cells, they have been mainly associated with increased tumorigenesis controlling different aspects from cell cycle regulation, stemness, or resistance to chemotherapies. In fewer cases, they have also been shown to oppose cancer progression, including by promoting cell death through the action of the p73/YAP transcriptional complex, in particular after chemotherapeutic drug exposure.
View Article and Find Full Text PDFSpleen tyrosine kinase (Syk) expression have been both positively and negatively associated with tumorigenesis. Our goal was to evaluate the contribution of Syk and its two splice variants, full length Syk (L) and short isoform Syk (S), in the tumor biology of colorectal cancer cells (CRC). The analysis of Syk expression in primary human colorectal tumors, as well as the analysis of TCGA database, revealed a high Syk mRNA expression score in colorectal cancer tumors, suggesting a tumor promotor role of Syk in CRC.
View Article and Find Full Text PDFThe current methods for measuring the DNA damage response (DDR) are relatively labor-intensive and usually based on Western blotting, flow cytometry, and/or confocal immunofluorescence analyses. They require many cells and are often limited to the assessment of a single or few proteins. Here, we used the Celigo image cytometer to evaluate the cell response to DNA-damaging agents based on a panel of biomarkers associated with the main DDR signaling pathways.
View Article and Find Full Text PDFTo treat colorectal liver metastases, intra-arterial chemotherapies may complete therapeutic arsenal. Drugs using intra-arterially are very heterogeneous. The aim of this study was to select the most efficient drug on a panel of colorectal cancer (CRC) cell lines (Caco-2, HCT 116, HT 29, SW 48, SW 480, SW 620) exposed for 30 min to 12 cytotoxic agents (doxorubicin, epirubicin, idarubicin, 5-FU, raltitrexed, gemcitabine, cisplatin, oxaliplatin, mitomycin C, irinotecan, streptozocin, paclitaxel) at different concentrations.
View Article and Find Full Text PDFResistance to castration is a crucial issue in the treatment of metastatic prostate cancer. Kinase inhibitors (KIs) have been tested as potential alternatives, but none of them are approved yet. KIs are subject of extensive metabolism at both the hepatic and the tumor level.
View Article and Find Full Text PDFInhibition of protein-DNA interactions represents an attractive strategy to modulate essential cellular functions. We reported the synthesis of unique oligoamide-based foldamers that adopt single helical conformations and mimic the negatively charged phosphate moieties of B-DNA. These mimics alter the activity of DNA interacting enzymes used as targets for cancer treatment, such as DNA topoisomerase I, and they are cytotoxic only in the presence of a transfection agent.
View Article and Find Full Text PDFChemoresistance, particularly to gemcitabine, is a major challenge in pancreatic cancer. The epidermal growth factor receptor (EGFR) and human epidermal growth factor receptors 2 and 3 (HER2, HER3) are expressed in many tumors, and they are relevant therapeutic targets due to their synergistic interaction to promote tumor aggressiveness and therapeutic resistance. Cocktails of antibodies directed against different targets are a promising strategy to overcome these processes.
View Article and Find Full Text PDFBcl-2-associated athanogen-6 (BAG6) is a nucleocytoplasmic shuttling protein involved in protein quality control. We previously demonstrated that BAG6 is essential for autophagy by regulating the intracellular localization of the acetyltransferase EP300, and thus, modifying accessibility to its substrates (TP53 in the nucleus and autophagy-related proteins in the cytoplasm). Here, we investigated BAG6 localization and function in the cytoplasm.
View Article and Find Full Text PDFWe describe herein the synthesis of a series of carboplatin derivatives with different functional groups at position 3 of the cyclobutane ring. This pharmacomodulation approach aims at facilitating the vectorisation of these analogues, via their subsequent conjugation to a drug delivery system. Five different derivatives bearing a hydroxy, keto, iodo, azido or amino function at position 3 were synthesised.
View Article and Find Full Text PDFThe human pregnane X receptor (hPXR) is activated by a large set of endogenous and exogenous compounds and plays a critical role in the control of detoxifying enzymes and transporters regulating liver and gastrointestinal drug metabolism and clearance. hPXR is also involved in both the development of multidrug resistance and enhanced cancer cells aggressiveness. Moreover, its unintentional activation by pharmaceutical drugs can mediate drug-drug interactions and cause severe adverse events.
View Article and Find Full Text PDFJ Pharm Biomed Anal
September 2020
The CDK4/6 inhibitors palbociclib and ribociclib are kinase inhibitors used in association with hormonal therapy for the management of patients with metastatic breast cancer. Like most kinase inhibitors, therapeutic drug monitoring may be used for personalize their dosage. To this aim, we developed and validated a sensitive and specific HPLC-MS/MS method for palbociclib and ribociclib quantification in blood samples.
View Article and Find Full Text PDFProstate cancer is the most commonly diagnosed malignancy in men. Its growth mainly relies on the activity of the androgen receptor (AR), justifying the use of androgen deprivation therapy as a gold standard treatment for the metastatic disease. Inhibition of the androgen axis using second generation antagonists has improved patients' survival, but is systematically confronted to resistance mechanisms, leading to a median survival that does not exceed 5 years.
View Article and Find Full Text PDFAlthough many patients with colorectal cancer initially respond to the chemotherapeutic agent oxaliplatin, acquired resistance to this treatment remains a major challenge to the long-term management of this disease. To identify molecular targets of oxaliplatin resistance in colorectal cancer, we performed an shRNA-based loss-of-function genetic screen using a kinome library. We found that silencing of ataxia-telangiectasia mutated and RAD3-related (ATR), a serine/threonine protein kinase involved in the response to DNA stress, restored oxaliplatin sensitivity in a cellular model of oxaliplatin resistance.
View Article and Find Full Text PDFPurpose: Colorectal cancer (CRC) is a heterogeneous disease that can be classified into distinct molecular subtypes. The aims of this study were 1) to compare claudin () gene expression in CRC samples and normal colon mucosa, and then in the different CRC molecular subtypes, and 2) to assess their prognostic value.
Patients And Methods: expression in CRC samples was analyzed using gene expression data for a cohort of 143 primary CRC samples, and compared in the same CRC samples classified into different molecular subtypes (C1 to C6 according to the Marisa's classification, and CMS1 to CMS4 of the consensus classification).
P300/CBP-associated factor (PCAF) and general control nonderepressible 5 (GCN5) are closely related epigenetic proteins, each containing an acetyltransferase domain and a bromodomain. Consistent with reported roles for these proteins in immune function, we find that PCAF-deficient macrophages exhibit a markedly reduced ability to produce cytokines upon stimulation with lipopolysaccharide (LPS). Investigating the potential to target this pathway pharmacologically, we show that chemical inhibition of the PCAF/GCN5 bromodomains is insufficient to recapitulate the diminished inflammatory response of PCAF-deficient immune cells.
View Article and Find Full Text PDFBackground: The irinotecan-induced phosphokinome changes in colorectal cancer (CRC) cells were used to guide the selection of targeted agents to be tested in combination with irinotecan.
Methods: Phosphokinome profiling with peptide arrays of tumour samples from nude mice xenografted with HT29 cells and treated or not with an effective dose of irinotecan was used to identify signalling pathways activated by irinotecan treatment. Then, drugs targeting these pathways were combined in vitro with irinotecan to test potential synergistic effect.
Cancer Lett
September 2018
Neuregulin 1 (NRG1), a ligand for HER3 and HER4 receptors, is secreted by both pancreatic tumor cells (PC) and cancer-associated fibroblasts (CAFs), the latter representing the most abundant compound of pancreatic stroma. This desmoplastic stroma contributes to Pancreatic Ductal Adenocarcinoma (PDAC) aggressiveness and therapeutic failure by promoting tumor progression, invasion and resistance to chemotherapies. In the present work, we aimed at disrupting the complex crosstalk between PC and CAF in order to prevent tumor cell proliferation.
View Article and Find Full Text PDFBackground: Our previous survey on first-in-human trials (FIHT) of monoclonal antibodies (mAbs) showed that, due to their limited toxicity, the recommended phase II dose (RP2D) was only tentatively defined.
Methods: We identified, by MEDLINE search, articles on single-agent trials of mAbs with an FIHT included in our previous survey. For each mAb, we examined tested dose(s) and dose selection rationale in non-FIHTs (NFIHTs).
Objective: Genetic P300/CBP-associated factor (PCAF) variation affects restenosis-risk in patients. PCAF has lysine acetyltransferase activity and promotes nuclear factor kappa-beta (NFκB)-mediated inflammation, which drives post-interventional intimal hyperplasia development. We studied the contributing role of PCAF in post-interventional intimal hyperplasia.
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