Search Results (160)

Colorectal cancer (CRC) remains a major cause of cancer-related mortality worldwide, largely due to the emergence of chemoresistance driven by metabolic adaptations. Among these alterations, lipid metabolic reprogramming has emerged as a critical determinant of tumor progression and therapeutic response. In particular, dysregulation of enzymes involved in phosphatidylcholine (PC) synthesis and remodeling, through the Kennedy pathway and the Lands cycle, has been associated with therapeutic resistance. Lysophosphatidylcholine acyltransferase 2 (LPCAT2), a key enzyme involved in PC remodeling, notably promotes lipid droplets (LD) accumulation in CRC cells and contributes to chemoresistance. In this context, natural compounds capable of modulating PC metabolism, such as the polyphenol resveratrol (RSV), may represent a relevant strategy to improve sensitivity to chemotherapies in chemoresistant colon tumor cells. In this study, RSV induced apoptosis and significantly reduced the proliferation of intrinsically resistant HT29 cells and SW620 cells engineered to overexpress LPCAT2. RSV also decreased the expression of key enzymes involved in the Kennedy pathway in chemoresistant CRC cell lines. These changes were accompanied by distinct time-dependent patterns of lipid droplet accumulation in the two cellular models. In addition, drug combination studies showed that RSV enhanced the response to 5-fluorouracil (5-FU), oxaliplatin (OXA) and the FOX regimen (5-FU + OXA, 1:1 ratio) with synergistic interactions for several dose combinations, together with favorable dose-reduction indices. Collectively, these in vitro findings indicate that RSV modulates PC-metabolism-related proteins and enhances chemotherapy sensitivity in resistant CRC models. Overall, our results identify RSV as a promising therapeutic strategy to target metabolic vulnerabilities associated with PC metabolism and overcome chemoresistance in CRC. Full article

Volatile organic compounds (VOCs) reflect cellular metabolic activities and may serve as non-invasive biomarkers in oncology. This study investigated whether acquired oxaliplatin resistance in colorectal cancer is associated with distinct volatilomic alterations. The human colorectal cancer cell line HCT116 and its oxaliplatin-resistant derivative (OXrHCT116) were analyzed under basal conditions and following oxaliplatin exposure. Chemoresistance was confirmed using dose–response, cell viability, and colony formation assays. VOCs were analyzed by headspace needle trap extraction coupled with gas chromatography–mass spectrometry (HS-NTE-GC-MS). OXrHCT116 cells exhibited markedly reduced oxaliplatin sensitivity, increased IC₅₀ values, and reduced proliferative and clonogenic capacity. Volatilomic profiling identified 55 significantly altered VOCs. Parental HCT116 cells displayed broader VOC diversity and higher turnover than OXrHCT116 cells. Hydrocarbons associated with lipid peroxidation and oxidative stress were more abundant in HCT116 cells, whereas resistant cells showed markedly reduced emission of these compounds. Additional alterations in aldehydes, alcohols, and aromatic compounds suggested reduced metabolic flux in resistant cells. Oxaliplatin exposure induced pronounced volatilomic changes in HCT116 cells but only minimal modulation in OXrHCT116 cells. These findings suggest that oxaliplatin resistance may be associated with distinct metabolic reprogramming and support VOC profiling as a promising approach for monitoring chemoresistance. Full article

Pancreatic ductal adenocarcinoma (PDAC) is considered as one of the most lethal malignancies, characterized by late diagnosis, aggressive local invasion, profound therapy resistance, and a suppressive tumor microenvironment. Currently known chemotherapy regimens for the treatment of PDAC are limited and typically depend on the stage of disease. For pre-surgery and post-surgery settings, modified combination of fluorouracil, leucovorin, irinotecan, and oxaliplatin are used. Gemcitabine/nab-paclitaxel is an alternative regimen used for the disease at advanced stage. However, modest efficacy and high toxicity are often associated with these treatments. Therefore, more efficacious, safer, and novel therapeutic options are urgently required. The natural product curcumin has been shown to exert promising anti-inflammatory, pro-apoptotic, and antimetastatic activities in PDAC models. Inspired by these initial reports, there has been a sustained effort in the medicinal chemistry community to develop chemotherapeutic agents for the treatment of PDAC based on the chemical architecture of curcumin. This review highlights recent developments of multiple classes of curcumin analogs as a credible and versatile class of investigational agents for addressing the unmet therapeutic needs of pancreatic cancer. Full article

More than 20 years after the discovery of lunasin, a clear shift in lunasin research is observable—from an initial focus on its direct in vitro anticancer effects toward strategies aimed at improving its bioavailability and repositioning it as a potential adjunct in cancer therapy. Lunasin, a soy-derived bioactive peptide, has been extensively studied for its antineoplastic properties. However, its limited oral bioavailability restrains its efficacy in clinical trials. Therefore, recent research on lunasin points towards the possibility of using it as an adjunct in cancer treatment, rather than as a stand-alone nutraceutical in humans. In preclinical models, in vitro and in vivo, lunasin can enhance the effects of standard anticancer drugs in breast and colon cancers. Research suggests that lunasin can potentiate the effects of drugs, such as tamoxifen, aspirin, cisplatin, and oxaliplatin, by sensitizing cancer cells to apoptosis, modulating cell cycle progression, reducing metastatic potential, and attenuating drug-resistance pathways, including PI3K/Akt, FAK/MAPK1/NF-κB, and integrin-mediated signaling. In combination with those drugs, lunasin exerts significant anticancer effects at concentrations substantially lower than those proven as effective in monotherapy, suggesting a potential role in dose reduction in conventional agents and, subsequently, mitigation of their adverse effects. Although the enhanced effect of those combinations has been shown in preclinical models, there is a distinct lack of human clinical trials in this matter. Available evidence supports a promising concept of lunasin as a molecular “priming” agent that might complement cytotoxic therapies rather than replace them. This combination-oriented paradigm may represent a shift in lunasin research and offer a novel direction for the use of bioactive peptides in precision oncology; however, further studies exploring this possibility, including human clinical trials, are needed to elucidate lunasin’s role in nutraceutical-assisted cancer therapy. Full article

Background: Fibrolamellar carcinoma (FLC) is a rare liver malignancy affecting adolescents. FLCs harbor a DNAJB1–PRKACA gene fusion that combines heat shock protein DNAJB1 with the catalytic subunit of protein kinase A. Surgery with systemic therapy provides 5-year survivals of 30–50%, but advanced disease remains largely incurable. Three-dimensional explants from 41 FLC patients were interrogated for drug sensitivity, resistance, and synergy against cytotoxics, targeted agents, and signal transduction inhibitors. Methods: Sterile specimens from histologically confirmed FLC patients were analyzed by Ex Vivo Analysis of Programmed Cell Death (EVA/PCD™) in a CLIA-licensed laboratory. Following mechanical and enzymatic disaggregation, explants underwent 72 h drug exposure. LC₅₀ values were derived from five-point dose–response curves and compared with a database of over 10,000 human tumor analyses. Synergy was assessed by combination index. In parallel, targeted metabolomic profiling was performed in five FLC patients using tandem MS/MS. Results: Forty-one samples were analyzed. Of 24 drugs selected, tumor-cell yields were adequate for testing in 18 (75%). Single-agent activity favored vorinostat, followed by phenformin and 6-diazo-5-oxo-L-norleucine. Combinations favored gemcitabine plus oxaliplatin (GEMOX) and 5-FU plus interferon. Metabolomic analysis identified distinct signature consistent with mitochondrial dysfunction and altered polyamine metabolism. Conclusions: The present findings are exploratory, and hypothesis-generating and should not be interpreted as evidence of clinical efficacy. Prospective clinical validation and mechanistic studies will be required to further define the therapeutic relevance of these observations in fibrolamellar carcinoma. Full article

Resistance to 5-fluorouracil (5-FU) and oxaliplatin (OXA) remains an obstacle in colorectal cancer (CRC) therapy, but the upstream mechanisms enabling adaptive survival remain unclear. Angiomotin (AMOT), a Hippo-YAP regulator, is expressed as two major isoforms, p130 and p80, but the contribution of isoform-specific AMOT regulation to chemoresistance is unknown. RNA-seq of OXA-resistant cells identified AMOT as a candidate determinant, and its isoform-specific regulation and functional relevance were then examined in OXA- and 5-FU-resistant CRC sublines. AMOT-p80 was preferentially upregulated, whereas AMOT-p130 remained largely unchanged. Common AMOT pre-mRNA was elevated, whereas p130-specific pre-mRNA was unchanged, consistent with preferential transcriptional activation favoring the p80 isoform. Functionally, AMOT depletion minimally affected basal viability but significantly sensitized resistant cells to 5-FU or OXA, with increased apoptotic responses. AMOT silencing reduced nuclear YAP and lowered c-Myc and Cyclin D1 protein levels, whereas AMOT-p80 re-expression restored nuclear YAP, with recovery of c-Myc/Cyclin D1 levels and drug tolerance. YAP knockdown attenuated these outputs and blunted the additional effect of AMOT depletion. AMOT-p80 overexpression in parental cells increased c-Myc/Cyclin D1 protein levels and enhanced tolerance to 5-FU and OXA. These findings suggest that preferential AMOT-p80 upregulation is linked to YAP-associated chemoresistant phenotypes in CRC cells. Full article

Background: Most patients with hepatocellular carcinoma (HCC) present with advanced disease and have limited systemic treatment options. Oxaliplatin shows clinical activity in HCC but its effectiveness is frequently curtailed by intrinsic and acquired resistance. We sought to systematically identify genetic vulnerabilities that increase oxaliplatin sensitivity in HCC. Methods: Genome-scale negative-selection CRISPR–Cas9 screens were conducted in two genetically distinct HCC cell lines (Hep3B and MHCC-97H) under low-dose oxaliplatin to discover conserved determinants of sensitivity. Selected DNA damage response (DDR) hits were validated. An oxaliplatin-resistant MHCC-97H subline was generated for transcriptomic profiling to characterize resistance-associated programs. Screen results were integrated with TCGA-LIHC expression and survival data to evaluate clinical relevance. Additionally, we analyzed bulk RNA-seq data from biopsy specimens collected from 36 HCC patients prior to initiation of hepatic arterial infusion chemotherapy (HAIC), comparing expression levels of the DDR genes between patients with objective response and non-responders. Results: Screens in both cell lines converged on DDR pathways, particularly nucleotide excision repair (NER) and the Fanconi anemia/interstrand crosslink repair network; shared sensitizers included ERCC4 (XPF), FANCE and SLX4. Validation experiments showed that disruption of representative DDR factors (POLH and XPA) synergistically increased oxaliplatin efficacy at concentrations as low as 0.5 μM. Transcriptomic analysis of the resistant MHCC-97H subline revealed coordinated upregulation of DNA repair programs, G2/M checkpoint and E2F target signatures, and epithelial–mesenchymal transition features. Integration with TCGA-LIHC data demonstrated frequent overexpression of many screen-identified DDR genes in primary HCC and an association between higher expression of selected factors and poorer patient survival. In the HAIC cohort, several DDR genes, including ATR, BRCA2, CDK7, MUS81, MUTYH, PARG, POLH, POLK and XPA, were significantly lower in the objective response group. Conclusions: DDR components represent candidate biomarkers and therapeutic targets whose inhibition may enhance oxaliplatin efficacy in HCC. Full article

In this study, we present new data about the cytotoxic activity of metal complexes of salinomycin with Co(II), Cu(II) and Zn(II) against human cervical cancer (HeLa) and melanoma (A375, SH-4) cell lines. The effect of the compounds on cell viability and proliferation was evaluated in short-term experiments (up to 72 h) with monolayer cultures using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test, neutral red uptake (NR), crystal violet staining (CV) and double staining with acridine orange (AO) and propidium iodide (PI). The cytotoxic effect of the metal complexes of salinomycin was found to be comparable and even superior to that of the commercial antitumor agents cisplatin and oxaliplatin. Long-term experiments revealed the ability of the compounds to completely suppress 3D cell growth when applied at concentrations ≥ 3.1 μM (for HeLa cells) and ≥6.2 µM (for A375 cells). Embryonic Lep-3 cells are highly sensitive to the influence of the complexes investigated, whereas non-tumor HaCaT human keratinocytes exhibit relatively higher resistance to their cytotoxic effect compared to tumor cell lines. The Zn(II) disalinomycinate exerted the highest selectivity index among the tested compounds against melanoma cells, whereas the non-coordinated antibiotic showed pronounced selectivity toward HeLa cells. Full article

Glucosylceramide synthase (GCS) catalyzes ceramide glycosylation in response to cell stress that produces glucosylceramide and other glycosphingolipids. GCS overexpression is a cause of drug resistance and enriches cancer stem cells (CSCs) during cancer chemotherapy. Previous studies showed that GCS modulates the expression of p53 mutants and oncogenic gain-of-function (GOF) in heterozygous knock-in cell models (TP53 R273H^−/+). However, it is unclear whether GCS can modulate the effects of homozygous p53 mutations, which are common in many cancer cases. We report herewith that inhibition of GCS, via UGCG knockout and using an inhibitor (Genz-161), effectively re-sensitizes drug resistance and diminishes CSCs in colon cancer cells carrying the homozygous p53 R273H mutation. In aggressive WiDr cells carrying TP53 R273H mutation, knockout of UGCG gene using CRISPR/Cas9 editing or inhibition of GCS with Genz-161 sensitized cancer cells to oxaliplatin, irinotecan and paclitaxel. With decreased ceramide glycosylation in lipidomic profiling, both UGCG knockout and Genz-161 treatments substantially decreased wound healing, and diminished CSCs and tumor growth under chemotherapy. Interestingly, inhibition of RNA m⁶A methylation by neplanocin A markedly increased p53 function and reversed drug resistance. Mechanistic investigation revealed that GCS inhibition downregulated methyltransferase-like 3 (METTL3) expression and decreased RNA-m⁶A modification on mutant p53 R273H effects. Altogether, our findings demonstrate that ceramide glycosylation promotes METTL3 expression and RNA m⁶A methylation in response to drug-induced stress, thereby promoting mutant p53 expression and associated GOF. Conversely, inhibition of GCS can diminish CSCs and drug resistance via reduction in m⁶A modification and advance of p53-assocaited tumor suppressive function. GCS inhibition is an achievable approach for mutant cancer treatment. Full article

Background/Objectives: The aberrant epigenetic landscape of cancer cells has attracted wide attention, motivating the search for new epigenetically active drugs both for anticancer therapy and for overcoming the drug resistance promoted by epigenetic changes. The use of epi-drugs in cancer therapy requires consideration of the influence of applied treatment on epigenetic regulation of gene expression. Therefore, it is reasonable to screen epigenetically active compounds among the drugs widely used in clinical oncology. Methods: We applied the HeLa TI cell-based assay to analyze the epigenetic activity of 40 drugs including 22 chemotherapeutic, 2 immunotherapeutic, 13 targeted, and 3 palliative agents. Reactivation of the epigenetically silenced GFP reporter gene integrated into the genome of HeLa TI cells was assessed using flow cytometry. Results: Statistically significant increases in the proportions of GFP-positive cells were demonstrated for the alkylating agent chlorambucil; the antimetabolites cytarabine, fluorouracil, gemcitabine, and pemetrexed; the platinum-based compounds cisplatin, and oxaliplatin; the topoisomerase inhibitor topotecan; and the antimicrotubule agents docetaxel, vincristine, and eribulin. Epigenetic activity was also detected for the targeted-therapy agents AZD8055, wortmannin, and cetuximab, as well as for the corticosteroid dexamethasone. Thus, epigenetic activity was revealed for 15 drugs widely used in cancer therapy, which possess different modes of action. Conclusions: Our findings show that many anticancer therapy agents modulate the epigenetic landscape of cancer cells, providing a rationale for expanding their therapeutic applications and enhancing the efficacy of combination strategies by overcoming epigenetically driven chemoresistance. Full article

Colorectal cancer (CRC) remains a major cause of cancer-related deaths in advanced disease, and activating KRAS/NRAS mutations limit the use of anti-EGFR antibodies to RAS–wild-type tumors. The cellular prion protein (PrP^C) has been linked to aggressive and chemoresistant CRC, but its extracellular partners and functional relevance in KRAS-mutant disease are not fully defined. Here, we examined extracellular PrP^C complexes and PrP^C-associated signaling in CRC cell lines and xenografts using a neutralizing PrP^C monoclonal antibody. Across a CRC panel that included SNU-C5/WT and its 5-fluorouracil- and oxaliplatin-resistant derivatives, HT-29 (KRAS–wild-type), and HCT-8 and LoVo (KRAS-mutant), co-immunoprecipitation showed that PrP^C forms complexes with the 37/67 kDa laminin receptor (RPSA), with PrP^C–RPSA association particularly increased in KRAS-mutant HCT-8 and LoVo cells. PrP^C protein levels were higher in KRAS-mutant HCT-8, SW620, and SNU-407 cells than in HT-29, and PrP^C neutralization reduced viability in all four lines. Accordingly, we assessed upstream RAS activity and found that active RAS (RAS-GTP) was higher in KRAS-mutant cells than in HT-29, and PrP^C treatment was associated with reduced RAS-GTP levels. In the same KRAS-mutant setting, basal AKT phosphorylation exceeded that in HT-29, and PrP^C treatment lowered AKT phosphorylation without changing total AKT. Moreover, PrP^C treatment was associated with reduced ERK1/2 phosphorylation in KRAS-mutant cells, suggesting attenuation of downstream RAS pathway output. These signaling changes coincided with a decrease in the S-phase fraction and an increase in G1. In an HCT-8 (KRAS G13D) xenograft model, PrP^C monotherapy inhibited tumor growth in a dose-dependent manner, and 5-fluorouracil (5-FU) monotherapy produced an intermediate effect. The combination of PrP^C (10 mg/kg) and 5-FU (20 mg/kg) yielded the greatest tumor growth inhibition among the tested regimens. Consistent with this enhanced tumor control, immunofluorescence of xenograft tissues showed that PrP^C, particularly with 5-FU, reduced intratumoral PrP^C and PCNA and decreased CD31-positive microvessels and α-SMA–positive vessel structures. Taken together, these findings suggest that extracellular PrP^C supports RAS–AKT signaling, proliferation, and tumor-associated angiogenesis in KRAS-mutant colorectal cancer, and that PrP^C neutralization additively enhances 5-fluorouracil activity in KRAS-mutant models. The data provide a preclinical basis for evaluating PrP^C antibodies in combination with fluoropyrimidine-based regimens in patients with KRAS-mutant CRC. Full article

Colorectal cancer (CRC) progression and therapy resistance are driven in part by metabolic reprogramming and the persistence of cancer stem-like cells (CSCs). The seven in absentia homolog 2 (SIAH2)/with-no-lysine kinase 1 (WNK1) signaling axis has emerged as a potential regulator of these processes, yet its functional role in CRC metabolism and tumor–stroma crosstalk remains incompletely understood. Integrated analyses of The Cancer Genome Atlas–Colon Adenocarcinoma (TCGA-COAD) and Gene Expression Omnibus (GEO, GSE17538) datasets revealed significant upregulation of SIAH2 and WNK1 in CRC tissues, with strong positive correlations to glycolysis- and hypoxia-associated genes, including PFKP, LDHA, BPGM, ADH1A, ADH1B, and HIF-1α. Single-cell and clinical profiling further demonstrated preferential enrichment of SIAH2 in undifferentiated, stem-like tumor cell populations. Functional studies across multiple CRC cell lines showed that SIAH2 silencing suppressed proliferation, clonogenic growth, tumor sphere formation, and cell-cycle progression, whereas SIAH2 overexpression exerted opposite effects. Seahorse extracellular flux analyses established that SIAH2 promotes glycolytic capacity and metabolic flexibility. At the protein level, SIAH2 regulated glycolytic enzymes and WNK1/hypoxia-inducible factor-1α (HIF-1α) signaling, effects that were amplified by cancer-associated fibroblast (CAF)-derived conditioned medium. CAF exposure enhanced SIAH2 expression, CSC spheroid growth, and resistance to fluorouracil, leucovorin, and oxaliplatin (FOLFOX) chemotherapy, whereas SIAH2 depletion effectively abrogated these effects. Collectively, these findings identify the SIAH2/WNK1 axis as a central metabolic regulator linking glycolysis, CSC maintenance, and microenvironment-driven therapy resistance in CRC, highlighting its potential as a therapeutic target. Full article

Pt complexes have been used in human and veterinary oncology for more than 50 years and represent one of the most significant groups of cytostatics. There are a lot of Pt-based compounds, such as cisplatin, carboplatin and oxaliplatin, which exhibit high efficiency against many tumors. Their broad application in oncology medicine and improper waste disposal induce environmental pollution by platinum cytostatics and their metabolites. They can cause toxic effects to fauna and flora, even at low concentration levels. Currently used technologies for wastewater treatment are not sufficient in the case of platinum-based metabolites. Their high resistance and toxicity of their degradation byproducts pose a serious problem. In this review, currently applied platinum-based cytostatics, their possible metabolic mechanisms, environmental impact and technological methods for their removal from wastewater and patients’ urine are summarized. Special attention is paid to adsorption methods. Full article

Colorectal cancer (CRC) demonstrates favorable clinical outcomes when diagnosed at an early stage; however, the prognosis declines substantially following recurrence or distant metastasis. Increasing evidence indicates that cancer stem cells (CSCs) are pivotal contributors to tumor recurrence, metastatic dissemination, and therapeutic resistance. The present study aimed to identify CSC-associated biomarkers through spatial transcriptomic profiling of normal colonic mucosa, primary CRC, and liver metastatic tissues, and to evaluate their functional relevance in CRC progression. Spatial transcriptomic analysis revealed that CCN2 was preferentially enriched within CSC clusters of primary CRC tissues, whereas APOC2 was predominantly upregulated in liver-metastatic CSCs. Functional validation of CCN2 was performed by establishing CCN2-knockout HCT116 cell lines using the CRISPR-Cas9 system. Loss of CCN2 expression markedly attenuated cell proliferation, migration, invasion, and oxaliplatin resistance compared with control cells. Furthermore, immunohistochemical analysis of tissue microarrays demonstrated a significant positive correlation between CCN2 expression and CSC markers SOX2 and Nestin. Collectively, these findings suggest that CCN2 functions as a central regulator of stemness and malignant potential in CRC and may represent a promising therapeutic target to prevent recurrence and metastasis. Additional mechanistic studies are warranted to further elucidate the molecular pathways of CCN2 and to validate the role of APOC2 in liver-metastatic CRC stem cells. Full article