Monitoring melanoma patients on treatment reveals a distinct macrophage population driving targeted therapy resistance
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE229908 | GEO | 2023/12/01
REPOSITORIES: GEO
Similar Datasets
Project description:Resistance to targeted therapy remains a major clinical challenge in melanoma patients. To uncover resistance mechanisms, we performed single cell RNA sequencing of fine needle aspirates from resistant and responding tumors from melanoma patients before and during BRAFi/MEKi treatment. Among the genes most differentially expressed between malignant cells from resistant vs. responding tumors was POSTN encoding the secreted factor periostin. POSTN was predicted to predominantly signal to a macrophage population associated with targeted therapy resistance (TTR). Accordingly, tumors from patients with fast disease progression after targeted therapy exhibited high POSTN expression levels as well as high numbers of TTR macrophages, and POSTN was able to polarize macrophages towards a TTR phenotype. In a mouse model in vivo, POSTN expression protected melanoma from targeted therapy, which was associated with a phenotype change of intratumroal macrophages. Finally, polarized TTR macrophages protected melanoma cells from MEKi-induced killing through CD44 receptor expression on melanoma cells. Thus, interfering with the protective activity of TTR macrophages might represent a strategy to overcome resistance to targeted therapy in melanoma.
2024-05-08 | GSE262779 | GEO
Project description:Nearly 50% of cutaneous melanomas carry activating mutations on the BRAF oncogene, and the combination of BRAF- and MEK-inhibitors (BRAF/MEKi) is frequently used for their clinical management. One major drawback of BRAF/MEKi targeted therapy is the rapid development of therapeutic resistance, which can occur via multiple mechanisms, including the metabolic rewiring of cancer cells that often involves the upregulation of mitochondrial bionergetics and NAD+ biosynthetic pathways. mTORC2 is a signaling complex that requires the presence of its essential RICTOR subunit to play its regulatory functions in cell growth and metabolism. mTORC2 is believed to play mostly pro-oncogenic roles in several tumor types, including melanoma. However, bioinformatics analysis of TCGA melanoma patients’ database revealed that low RICTOR levels in tumors correlate with an overall worse clinical outcome. GSEA analysis of low-RICTOR tumors evidenced also a gene expression signature suggestive of activation of mitochondrial energy producing pathways. On these bases, we have hypothesized that inhibition of mTORC2 activity may render BRAFV600E melanoma cells resistant to BRAFi/MEKi. We show here that RICTOR/mTORC2-deficient cells are intrinsically tolerant to BRAFi/MEKi, and anticipate the onset of resistance to BRAFi after sustained drug exposure both in vitro and in vivo, indicating that mTORC2 activity normally opposes the acquisition of targeted therapy resistance in BRAFV600E melanomas. Mechanistically, RICTOR-deficient cells show an enhanced mitochondrial respiratory potential and increased expression of nicotinamide phosphoribosyltransferase (NAMPT) protein, the rate-limiting enzyme of NAD+ salvage pathway, and pharmacological inhibition of these processes in RICTOR-deficient cells is sufficient to restore sensitivity to BRAFi. Thus, our work identifies a novel role for mTORC2 in favoring the responses of BRAF-mutated melanoma cells to targeted therapy, and suggest that the evaluation of the intratumor level of RICTOR may help to predict the responses of melanoma patients to these treatments.
2024-05-23 | PXD045346 | Pride
Project description:About 25% of melanoma harbor activating NRAS mutations, which are associated with aggressive disease therefore requiring a rapid anti-tumor intervention. However, no efficient targeted therapy options are currently available for patients with NRAS-mutant melanoma. MEK inhibitors (MEKi) appear to display a moderate anti-tumor activity and also immunological effects in NRAS-mutant melanoma, providing an ideal backbone for combination treatments. In this study, the MEKi binimetinib, cobimetinib, and trametinib combined with the BRAF inhibitors (BRAFi) encorafenib, vemurafenib, and dabrafenib were investigated for their ability to inhibit proliferation, induce apoptosis and alter the expression of immune modulatory molecules in sensitive NRAS-mutant melanoma cells using 2D and 3D cell culture models and transcriptome analyses. Furthermore, NRAS-mutant melanoma cells resistant to the three BRAFi/MEKi combinations were established to characterize the mechanisms contributing to their resistance. All BRAFi induced a stress response in the sensitive NRAS-mutant melanoma cells thereby significantly enhancing the anti-proliferative and pro-apoptotic activity of the MEKi analyzed. Furthermore, BRAFi/MEKi combinations upregulated immune relevant molecules, such as ICOS-L, components of antigen-presenting machinery and the “don’t eat me signal” molecule CD47 in the melanoma cells. The BRAFi/MEKi-resistant, NRAS-mutant melanoma cells counteracted the molecular and immunological effects of BRAFi/MEKi by upregulating downstream mitogen-activated protein kinase pathway molecules, inhibiting apoptosis and promoting immune escape mechanisms. Together, this study reveals potent molecular and immunological effects of BRAFi/MEKi in sensitive NRAS-mutant melanoma cells that may be exploited in new combinational treatment strategies for patients with NRAS-mutant melanoma.
2023-11-14 | GSE245262 | GEO
Project description:In a prospective clinical study, we show that increased serum IGF1 levels in a patient may be a predictive marker of melanoma escape to therapies targeting MAPK pathway (BRAFi/MEKi). In addition, our in vitro and in vivo studies suggest that the response of targeted therapies-resistant melanoma cells to IGF1R inhibitor appears to correlate with the level of IGF1 secretion. Overall, our results suggest that monitoring serum IGF1 levels would individually identify melanoma patients who escape BRAFi/MEKi treatment and may benefit from a combination of targeted therapies and IGF1 signaling inhibition to overcome resistance.
2023-10-30 | GSE239284 | GEO
Project description:Background Main drawback of BRAF/MEK inhibitors (BRAF/MEKi)-based targeted therapy in the management of BRAF- mutated cutaneous metastatic melanoma (MM) is the development of therapeutic resistance. We aimed to define in this context the specific role of mTORC2, a signaling complex defined by the presence of the essential RICTOR subunit and regarded as an oncogenic driver in several tumor types, including MM. Methods After analyzing the TCGA MM patients’ database to explore both overall survival and molecular signatures as a function of intra-tumor RICTOR levels, we investigated the effects of RICTOR downregulation in BRAF V600E MM cell lines on their response to BRAF/MEKi in vitro. We performed a proteomic screening to identify proteins modulated by changes in RICTOR expression and Seahorse analysis to evaluate the effects of RICTOR depletion on mitochondrial respiration. The combination of BRAFi with drugs targeting proteins and processes emerged in the proteomic screening was carried out on RICTOR-deficient cells in vitro and in a xenograft setting in vivo. Results We found that low RICTOR levels in MM correlate with an overall worse clinical outcome. GSEA of low- RICTOR tumors revealed a gene expression signature suggestive of activation of the mitochondrial Electron Transport Chain (ETC) energy producing pathway. RICTOR-deficient BRAF V600E cells are intrinsically tolerant to BRAFi/MEKi and anticipate the onset of resistance to BRAFi upon prolonged drug exposure. In RICTOR- depleted cells, both mitochondrial respiration and expression of nicotinamide phosphoribosyltransferase (NAMPT) are enhanced, while their pharmacological inhibition restores sensitivity to BRAFi. Conclusions Our work unveils a novel tumor suppressing role for mTORC2 in the responses of BRAF V600E melanoma cells to targeted therapy and identifies the NAMPT-ETC axis as a potential therapeutic vulnerability of low- RICTOR tumors. Importantly, our findings support the concept that the evaluation of intra-tumor RICTOR levels in MM has a prognostic value, and may help predicting the response of patients to targeted therapy.
2024-06-22 | PXD050614 | Pride
Project description:Oncogenic KRAS signaling is a hallmark of pancreatic ductal adenocarcinoma (PDAC), a lethal malignancy with few treatment options. A major roadblock in deploying therapies targeting the KRAS-MAPK pathway is the rapid emergence of resistant cancer cells. However, molecular mechanisms underlying adaptive targeted therapy resistance in PDAC are poorly understood. Here we find SETD5 (SET domain containing 5) as a major epigenetic driver of PDAC resistance to MEK1/2 inhibition (MEKi). SETD5 is identified in a genetic screen of annotated methyltransferases that mediate MEKi toxicity in PDAC cells. SETD5 expression is induced upon PDAC cells and tumors acquring MEKi-resistance and SETD5 deletion restores vulnerability of refractory PDAC to MEKi therapy in mouse models and patient-derived xenografts (PDX). SETD5 lacks intrinsic histone methyltransferase activity and rather scaffolds a distinct corepressor complex that regulates HDAC3 and G9a catalytic behaviors to couple selective deacetylation with methylation of histone H3 at lysine 9 (H3K9). Gene silencing by the SETD5 complex regulates a network of known drug resistance pathways to reprogram cellular responses to MEKi, a resistance program disrupted by G9a and HDAC3 blockade. Combinatorial pharmacological targeting of MEK1/2, G9a, and HDAC3 results in sustained tumor growth inhibition in murine and human models of PDAC. Together, our work uncovers SETD5 as a master epigenetic regulator of acquired MAPK-pathway therapy resistance and suggests an efficacious clinical path for MEKi in PDAC.
2020-05-06 | GSE142046 | GEO
Project description:Therapies targeting oncogene addiction have had a tremendous impact on tumor growth and patient outcome, but drug resistance continues to be problematic. One approach to deal with the challenge of resistance entails extending anti-cancer treatments beyond targeting cancer cells by additionally altering the tumor microenvironment. Understanding how the tumor microenvironment contributes to the evolution of diverse resistance pathways could aid in the design of sequential treatments that can elicit and take advantage of a predictable resistance trajectory. Tumor associated macrophages are often the most abundant immune cell found in tumors. Here, we used clinically relevant in vivo Braf-mutant melanoma models with fluorescent markers to track the stage-specific changes in macrophages under targeted therapy with Braf/Mek inhibitors and assessed the dynamic evolution of the macrophage population generated by therapy pressure-induced stress. During the onset of a drug-tolerant persister state, Ccr2+ monocyte-derived macrophage infiltration rose, suggesting that macrophage influx at this point could facilitate the onset of stable drug resistance after several weeks of treatment. Comparison of melanomas that develop in a Ccr2-proficient or deficient microenvironment demonstrated that lack of melanoma infiltrating Ccr2+ macrophages delayed onset of resistance and shifted melanoma cell evolution towards unstable resistance. Unstable resistance was characterized by sensitivity to targeted therapy when factors from the microenvironment were lost. Importantly, this phenotype was reversed by co-culturing melanoma cells with Ccr2+ macrophages. Overall, this study demonstrates that the development of resistance may be directed by altering the tumor microenvironment to improve treatment timing and the probability of relapse.
2023-05-09 | GSE226835 | GEO
Project description:While effective therapy is available for melanoma patients harbouring BRAF mutations, to date, the efficient therapeutic approaches for NRAS-mutant melanoma patients are limited. Therapeutic regimen involving combinatorial inhibition of MEK1/2 and CDK4/6 prove to be beneficial as targeted therapy for NRAS-mutant melanoma. Yet, only a subset of melanoma patients responded to this treatment, whereas acquired resistance eventually emerge in responders. Upon prolonged therapy with MEK1/2 and CDK4/6 inhibitors cells switch to fully drug-resistant or senescent phenotype in vitro. Consequently, there is a necessity to portray cell populations sensitive to targeted therapy, but also cell transitions associated with NRAS-mutant melanoma resistance. To define transcriptional states arising under indicated therapy and cell fate decisions governing resistance, we performed single-cell RNA sequencing at four distinguished time points during treatment. In this study, we identified a cell population highly enriched in calcium signalling, among others, associated with positive drug response. In particular, prolonged expression of ATP-gated ion channel P2RX7 was related to a senescent-like phenotype. Next, we described an immune-like melanoma state that acquired drug resistance and re-enter the cell cycle under treatment, as well as cell populations with intrinsic potential to evade drug pressure.
2023-04-26 | GSE230538 | GEO
Project description:Multiple BRAF inhibitor resistance mechanisms have been described, however their relative frequency, clinical correlates, and effect on subsequent therapy have not been assessed in patients with metastatic melanoma. Excised progressing BRAFV600 mutant melanoma metastases (Prog) from patients treated with dabrafenib (n=22) or vemurafenib (n=8) were analyzed for known resistance mechanisms. Oncogenic signaling in Prog and matched pre-treatment tumors was examined using gene expression analysis. Resistance mechanisms were correlated with clinicopathologic features and outcome. A resistance mechanism was identified in 21/38 (55%) Prog samples from 30 patients; BRAF splice variants (n=12, 32%), N-RAS mutations (n=3, 8%), BRAF amplification (n=3, 8%), MEK1/2 mutations (n=3, 8%) and an AKT1 mutation (n=1, 3%). Four Progs tumours displayed multiple resistance mechanisms, and four patients with multiple Progs demonstrated inter-tumoral heterogeneity of resistance mechanisms. Six (21%) of 29 Progs showed loss of MAPK activity by gene expression analysis. These MAPK-inhibited Progs had unknown resistance mechanisms, and these patients had a shorter progression-free survival than patients with MAPK re-activated Progs. There were no responses to subsequent targeted therapy, even when the identified mechanism of resistance was predicted to be responsive. Heterogeneity of resistance mechanisms was common between patients, within patients and within individual tumors. The MAPK pathway remained inhibited in a subset of resistant tumors with unknown mechanisms of resistance, and the outcomes of patients with these tumors are poor. The use of sequential targeted therapies based on the molecular characteristics of a single progressing biopsy is unlikely to provide improved clinical outcomes. Total RNA was obtained from fresh-frozen melanoma tumour samples from patients before commencing treatment with dabrafenib or vemurafenib and at time of tumour progression.
2014-02-19 | E-GEOD-50509 | biostudies-arrayexpress
Project description:Intratumor heterogeneity fosters the evolution of the genome leading to metastatic progress and therapy resistance. Here, we investigate the relative contribution of genomic heterogeneity involving mutations and CNAs as prognostic and predictive determinants for disease recurrence in early-stage colon cancer. We combined targeted next-generation sequencing (NGS) and SNP arrays on a retrospective cohort of untreated stage II colon cancer patients to assess the association of genomic subclonality with time to recurrence (TTR).
2021-12-01 | GSE172190 | GEO