Chemoresistance remains a major cause of treatment failure in colorectal cancer (CRC), yet the metabolic mechanisms sustaining efflux-mediated drug resistance are not fully defined. Here, we identify ATP-citrate lyase (ACLY) as a metabolic regulator linking citrate-dependent acetyl-CoA production to epigenetic control of MDR1/ ABCB1 expression. Using genetic and pharmacologic approaches, we show that ACLY catalytic activity contributes to the maintenance of histone acetylation at H3K9 and H4K16 and supports MDR1 transcription in CRC cells. Consistently, ACLY overexpression enhances, whereas its inhibition reduces, MDR1 expression and associated resistance-related transcriptional programs. In human CRC specimens, ACLY and MDR1 levels positively correlate, with a stronger association observed in advanced-stage tumors, supporting clinical relevance of this metabolic-epigenetic axis. Metabolic tracing with 13C-glucose suggests that perturbation of citrate flux influences ACLY-associated pathways and acetyl-CoA availability. In this context, vitamin C treatment reduces citrate-derived acetyl-CoA and ACLY phosphorylation and is associated with global histone deacetylation and decreased MDR1 expression in vitro and in KRAS-mutant patient-derived xenografts. Together, these findings highlight ACLY-dependent acetyl-CoA production as a potential metabolic vulnerability linked to epigenetic regulation of drug efflux programs in CRC. Targeting this metabolic-chromatin axis may represent a strategy to modulate MDR1-associated chemoresistance.

Anti-epidermal growth factor receptor (EGFR) therapies are the most recommended first-line treatment for RAS/RAF wild-type unresectable metastatic colorectal cancer (CRC) according to the European Society for Medical Oncology guidelines. However, primary resistance renders this treatment ineffective for almost 40% of patients. Our previous work identified Aurora kinase A (AURKA) as a key resistance driver through non-canonical, Hippo-independent Yes-associated protein 1 (YAP1) activation. However, the role of the other main Hippo coactivator, transcriptional coactivator with PDZ-binding motif (TAZ), in this resistance mechanism remains unexplored. By integrating preclinical in vitro and in vivo models, including cell lines and patient-derived xenografts, with RNA sequencing, we investigated the impact of TAZ overexpression in cetuximab resistance driven by the AURKA/YAP1 axis. Our findings reveal that TAZ overexpression sustains YAP1-mediated resistance and stemness. Even under YAP1 suppression, TAZ-overexpressing cells remain unresponsive to anti-EGFR therapies, whereas dual YAP1/TAZ silencing restores sensitivity. Treatment with alisertib, a phase III AURKA inhibitor, simultaneously destabilizes YAP1 and TAZ, restoring anti-EGFR efficacy by suppressing stemness. Transcriptomic analyses further show that AURKA inhibition and dual YAP1/TAZ suppression disrupt stem-like traits and reveal transcriptional deregulations affecting nucleotide metabolism. These findings demonstrate that AURKA orchestrates YAP1/TAZ crosstalk, which is crucial for driving stemness and resistance to anti-EGFR therapies, highlighting AURKA inhibitors as a promising strategy to enhance anti-EGFR therapies in metastatic CRC.

BackgroundDNA polymerase theta (POLQ) is a translesion synthesis polymerase essential for the repair of double strand breaks by the error-prone TMEJ (Theta Mediated End Joining) pathway. Although POLQ participates in maintaining genome stability, several studies have shown that its overexpression correlates with cancer progression and poor prognosis. Due to the fact that its role as a biomarker in pancreatic cancer remains unexplored, we aimed to study the usefulness of POLQ H-score as a prognostic factor in a pancreatic cancer patient cohort.MethodsWe evaluated POLQ gene expression using a web-based tool to deliver gene expression profiling and interactive analyses based on TCGA and GTEx (GEPIA) and we examined the POLQ immunostaining in 152 biliopancreatic cancer surgical specimens using tissue microarrays. Association with survival was evaluated by Kaplan Meier curves and uni-multivariate Cox regression.ResultsGEPIA analysis showed statistical differences according to POLQ mRNA levels in Disease Free Survival (DFS) (log rank 0.023, HR 2.8, p=0.029) and Overall Survival (OS) (log rank 0.011, HR 3.1, p=0.016). For immunohistochemistry (IHC) evaluation, POLQ H-score was calculated, and showed statistical differences for OS in Kaplan Meier curves (log rank 0.001) and uni-multivariate analysis (HR 2.27; 95% CI 1.24-4.15, p=0.008).ConclusionsOur results indicate that POLQ is an independent prognostic factor in pancreatic cancer when analyzed by immunostaining, which is in agreement with the results shown by the POLQ gene expression analysis (GEPIA).

In pancreatic ductal adenocarcinoma (PDAC), metabolic rewiring and resistance to standard therapy are closely associated. PDAC cells show enormous requirements for glucose‐derived citrate, the first rate‐limiting metabolite in the synthesis of new lipids. Both the expression and activity of citrate synthase (CS) are extraordinarily upregulated in PDAC. However, no previous relationship between gemcitabine response and citrate metabolism has been documented in pancreatic cancer. Here, we report for the first time that pharmacological doses of vitamin C are capable of exerting an inhibitory action on the activity of CS, reducing glucose‐derived citrate levels. Moreover, ascorbate targets citrate metabolism towards the de novo lipogenesis pathway, impairing fatty acid synthase (FASN) and ATP citrate lyase (ACLY) expression. Lowered citrate availability was found to be directly associated with diminished proliferation and, remarkably, enhanced gemcitabine response. Moreover, the deregulated citrate‐derived lipogenic pathway correlated with a remarkable decrease in extracellular pH through inhibition of lactate dehydrogenase (LDH) and overall reduced glycolytic metabolism. Modulation of citric acid metabolism in highly chemoresistant pancreatic adenocarcinoma, through molecules such as vitamin C, could be considered as a future clinical option to improve patient response to standard chemotherapy regimens.

Background Primary resistance to anti-EGFR therapies affects 40% of metastatic colorectal cancer patients harbouring wild-type RAS/RAF . YAP1 activation is associated with this resistance, prompting an investigation into AURKA’s role in mediating YAP1 phosphorylation at Ser397, as observed in breast cancer. Methods We used transcriptomic analysis along with in vitro and in vivo models of RAS/RAF wild-type CRC to study YAP1 Ser397 phosphorylation as a potential biomarker for cetuximab resistance. We assessed cetuximab efficacy using CCK8 proliferation assays and cell cycle analysis. Additionally, we examined the effects of AURKA inhibition with alisertib and created a dominant-negative YAP1 Ser397 mutant to assess its impact on cancer stem cell features. Results The RAS/RAF wild-type CRC models exhibiting primary resistance to cetuximab prominently displayed elevated YAP1 phosphorylation at Ser397 primarily mediated by AURKA. AURKA-induced YAP1 phosphorylation was identified as a key trigger for cancer stem cell reprogramming. Consequently, we found that AURKA inhibition had the capacity to effectively restore cetuximab sensitivity and concurrently suppress the cancer stem cell phenotype. Conclusions AURKA inhibition holds promise as a therapeutic approach to overcome cetuximab resistance in RAS/RAF wild-type colorectal cancer, offering a potential means to counter the development of cancer stem cell phenotypes associated with cetuximab resistance.

Not much has changed in the SCLC landscape over the past 40 years, apart from the addition of checkpoint inhibitors, which have been the most notable advance in clinical management since the 1980s. As a result, greater efforts are needed to develop more therapies to combat this type of cancer. Galectin-1 (Gal-1) has emerged as an interesting player due to its involvement in crucial roles in cancer development. Our objective was to assess whether Gal-1 has a prognostic role in SCLC outcomes and its potential for use in both monotherapy and combination with platinum-based therapy. We analyzed Gal-1 expression in 77 SCLC patients using RNA sequencing and in 81 patients using in-house immunohistochemistry (IHC). We evaluated the prognostic potential of Gal-1 using survival curves and Cox regression analysis. Additionally, we established a SCLC-PDX model and randomized it into four groups to assess the effects of Gal-1 inhibition in monotherapy and in combination with platinum-based therapy. To evaluate antitumor activity, T/C ratio was applied. Galectin-1 gene (LGALS1) expression showed a strong negative correlation with outcomes in SCLC patients with advanced disease (p = 0.007). Furthermore, IHC analysis revealed that in patients with advanced disease, a high Gal-1 score (Gal-1 score >3) and high Platelets to Lymphocytes Ratio (PLR > 186) as a combined variable presented a HR=3.07, 95% CI: 1.62, 5.79, p < 0.001, with a significant impact on survival (median time (weeks) for OS was 31 in the high/high group versus 41.1 in the other group). The SCLC-PDX model showed a significant reduction in tumor growth in both the OTX008 (T/C 66%) and carboplatin/etoposide (T/C 65%) groups, with the greatest effect attributable to the combination (T/C 46%). Our findings suggest that high levels of Gal-1 and PLR are associated with poorer OS in SCLC patients and can be useful as clinical prognostic biomarkers. Moreover, our in vivo model suggests that the inhibition of Gal-1 could be a novel potential therapy with a significant impact in combination with platinum-based therapy.

Supplementary Table S1 from Tagging Single-Nucleotide Polymorphisms in Antioxidant Defense Enzymes and Susceptibility to Breast Cancer

Supplementary Information and Tables 1-5 from Association Study of 69 Genes in the Ret Pathway Identifies Low-penetrance Loci in Sporadic Medullary Thyroid Carcinoma

Introduction: small-cell lung cancer (SCLC) is one of the most lethal malignancies. Its management is complex due to the lack of biomarkers and limited therapies. Galectin-1 (Gal-1) plays a major role in cancer development and progression. The aim of this study is to assess whether Gal-1 has a predictive role in the disease evolution and its therapeutic potential. Material and Methods: The expression level of Gal-1 was examined by using a public RNA-sequencing (77 SCLC patients) and in-house immunohistochemistry (IHC) performed on biopsies from 81 patients. Survival curves and Cox regression analysis were used to assess the prognostic potential of Gal-1. In addition, a SCLC-PDX model was carried out and treated with either OTX008, an inhibitor of Gal-1, or vehicle to assess the effects of Gal-1 inhibition on this disease in vivo. Results: Galectin-1 gene (LGALS1) expression showed a strong negative correlation with outcome in SCLC patients with advanced disease (p = 0.007). IHC unveiled that overall survival (OS) was significantly lower among extensive-stage SCLC (ES-SCLC) patient group with increased level of Gal-1 and platelet-to-lymphocyte ratio (PLR) (HR=3.07, 95% CI: 1.62, 5.79, p < 0.001). The SCLC-PDX model showed a significant reduction in tumor size (tumor growth inhibition [TGI] index 73%) without side effects. Discussion: in this study, high levels of Gal-1 and PLR were associated with poorer OS in SCLC patients, supporting their utility as clinical prognostic biomarkers. Moreover, the in vivo model suggests the inhibition of Gal-1 as a novel potential therapy for this disease with very poor prognosis.

Lung cancer is one of the main causes of death in developed countries, and non-small cell lung cancer (NSCLC) is the most frequent type (80% of patients). In advanced NSCLC, platinum-based chemotherapy is the frontline palliative treatment, but less than 5% of patients achieve prolonged survival. Immunotherapy has recently been proposed as the standard of care (SoC) as either monotherapy or in combination with chemotherapy for advanced NSCLC. The levels of expression of PD-L1 are the only predictive biomarkers for patient assessment. Although around 30% of patients receiving immunotherapy achieve 5-year survival, a significant number does not benefit from this novel therapeutic approach. Therefore, there is a need for novel strategies to improve clinical outcomes. The expression level of choline kinase α (ChoKα) is increased in a large number of human tumors, including NSCLC tumors, and constitutes an independent prognostic factor for early-stage NSCLC patients. Thus, ChoKα has been postulated as a new target drug in cancer therapy. The combination of cisplatin with novel targeted drugs such as choline kinase inhibitors may improve both the survival rates and the quality of life of NSCLC patients and may serve as the basis for the development of new therapeutic approaches. To that aim, we developed several in vitro and in vivo approaches to assess the antitumor activity of a novel combination regimen using cisplatin and ChoKα inhibitors. Our results suggest that a proper combination of specific inhibitors of the NSCLC prognostic factor ChoKα and platinum-based conventional chemotherapy might constitute a new, efficient treatment approach for NSCLC patients. This novel approach may help reduce the toxicity profile associated with cisplatin since, despite the advances in NSCLC management in recent years, the overall 5-year survival rate is still poor.

Colorectal cancer remains among the cancers with the highest incidence, prevalence, and mortality worldwide. Although the development of targeted therapies against the EGFR and VEGFR membrane receptors has considerably improved survival in these patients, the appearance of resistance means that their success is still limited. Overactivation of several members of the Ras-GTPase family is one of the main actors in both tumour progression and the lack of response to cytotoxic and targeted therapies. This fact has led many resources to be devoted over the last decades to the development of targeted therapies against these proteins. However, they have not been as successful as expected in their move to the clinic so far. In this review, we will analyse the role of these Ras-GTPases in the emergence and development of colorectal cancer and their relationship with resistance to targeted therapies, as well as the status and new advances in the design of targeted therapies against these proteins and their possible clinical implications.

New therapeutic targets are revolutionizing colorectal cancer clinical management, opening new horizons in metastatic patients' outcome.Polo Like Kinase1 (PLK1) inhibitors have high potential as antitumoral agents, however, the emergence of drug resistance is a major challenge for their use in clinical practice.Overcoming this challenge represents a hot topic in current drug discovery research.BI2536-resistant colorectal cancer cell lines HT29 R , RKO R , SW837 R and HCT116 R , were generated in vitro and validated by IG 50 assays and xenografts models by the T/C ratio.Exons 1 and 2 of PLK1 gene were sequenced by Sanger method.AXL pathway, Epithelial-to-Mesenchymal transition (EMT) and Multidrug Resistance (MDR1) were studied by qPCR and western blot in resistant cells.Simvastatin as a re-sensitizer drug was tested in vitro and the drug combination strategies were validated in vitro and in vivo.PLK1 gene mutation R136G was found for RKO R .AXL pathway trough TWIST1 transcription factor was identified as one of the mechanisms involved in HT29 R , SW837 R and HCT116 R lines, inducing EMT and upregulation of MDR1.Simvastatin was able to impair the mechanisms activated by adaptive resistance and its combination with BI2536 re-sensitized resistant cells in vitro and in vivo.Targeting the mevalonate pathway contributes to re-sensitizing BI2536-resistant cells in vitro and in vivo, raising as a new strategy for the clinical management of PLK1 inhibitors.

Aim Cetuximab is a standard-of-care treatment for KRAS wild-type metastatic colorectal cancer (mCRC), but it may also be effective in a subgroup of KRAS mutant patients by its immunomodulatory activity. Here, we explore if KIR (killer cell immunoglobulin-like receptor) genotyping can provide a significant added value in the clinical outcome of patients with KRAS mutant mCRC based on cetuximab treatment. Methods We included 69 patients with histologically confirmed mCRC and KRAS mutation, positive EGFR expression, and Eastern Cooperative Oncology Group performance status ≤2. Based on KIR gene content, haplotype (A or B) was defined and genotypes (AA or Bx) were grouped for each patient. Results We demonstrated with new evidence the immunomodulatory activity of cetuximab in patients with KRAS mutant mCRC. Patients with homozygous genotypes (AA or BB) showed shorter 12-month progression-free survival (PFS12) and poorer overall survival (OS) than those with heterozygotes (AB). Moreover, multivariate analysis confirmed stratification of patients based on genotype was an independent marker of PFS12 (HR 2.16) and the centromeric and telomeric distribution of KIRs was an independent predictor of both PFS12 (HR 2.26) and OS (HR 1.93) in patients with mCRC with KRAS mutation treated with cetuximab. Conclusions Selection of patients with mCRC based on their KIR genotypes opens a therapeutic opportunity for patients with KRAS mutation, and it should be tested in clinical trials in comparison with other alternatives with scarce benefit. Trial registration number NCT01450319 , EudraCT 2010-023580-18.

Background: Galectin-1 (Gal-1) plays major roles in cancer by modulating different processes leading to tumor development and progression. In the last years, it has been suggested as a promising target for anticancer therapy. Recently, aflibercept has shown high affinity for Gal-1. Here, we investigated how aflibercept could exert its antitumor activity via Gal-1-driven pathways in neuroendocrine carcinomas (NECs). Methods and Results: NEC tumor xenografts were used to assess the effect of aflibercept on Gal-1 functions. Aflibercept induced a significant reduction of Gal-1 at epithelial, stromal, and extracellular localizations in lung NEC, whereas this was not observed in colon NECs, which displayed low expression of Gal-1. Additionally, aflibercept significantly reduced p-VEGFR2 protein, extracellular matrix remodeling, epithelial-mesenchymal transition, and activation of cancer-associated fibroblast hampering cell invasion in lung NEC but not in colon NEC. Gal-1 screening in human NECs confirmed that pulmonary and pancreatic tumors displayed higher levels of Gal-1 than colon NECs, becoming good candidates to benefit from aflibercept treatment. Conclusions: The lack of validated predictive markers of aflibercept is a weakness for guaranteeing the best treatment management with this drug. This work provides new mechanistic insight of aflibercept depending on Gal-1. Thus, in tumors overexpressing Gal-1, aflibercept has not only an antiangiogenic effect but also prevents Gal-1-mediated tumor-stroma cross talk. The stronger aflibercept effect in tumors with high levels of Gal-1 points out this protein as a molecular marker to predict the efficacy of this agent not only for NECs but also for other tumors with high levels of this protein.

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