Search Results (91)

Background: In melanoma diagnostics key molecular markers, such as BRAF, NRAS, and KIT mutations also paved the way for targeted therapies. Immunotherapies, including immune checkpoint inhibitors like anti-CTLA-4 and anti-PD-1/PD-L1, have revolutionized treatment, improving survival outcomes for advanced-stage melanoma patients. Despite these advances, challenges such as resistance to targeted therapies and variability in patient responses to immunotherapy remain critical issues. The purpose of the project is to characterize the molecular landscape of a set of 28 malignant melanomas using next-generation sequencing, identify the prevalence and nature of class 3–5 variants (e.g., NRAS, BRAF, KIT, TP53), assess the genetic complexity and molecular patterns, and use these insights to inform personalized therapies and optimize patient stratification for potential combination strategies (targeted therapy followed by immunotherapy). Methods: We analyzed a set of malignant melanoma of the skin of 17 women (61%) and 11 men (39%) at the age of 23 to 85 years (median: 63 years) by tumor-only next generation sequencing. Results: 22/28 cases (79%) present a pathogenic or likely pathogenic variant with an allelic frequency of ≥5%. In total 42 distinct somatic pathogenic or likely pathogenic variants with an allelic frequency of ≥5% could be detected. The most frequent pathogenic molecular alteration in these melanomas were found in NRAS (25%) and BRAF (25%). The most frequent molecular alteration of unknown significance was found in FANDC2 (46%), NOTCH3 (39%), ARID1A (32%), PMS2 (32%), POLE (29%), NOTCH1 (29%), TSC2 (25%), SMARCA4 (25%), ATR (25%) and TERT (21%). Conclusions: While NRAS and BRAF were the most frequent actionable alterations (each 25%), a broad spectrum of variants of unknown significance (e.g., FANDC2, NOTCH3, ARID1A, PMS2, POLE, NOTCH1, TSC2, SMARCA4, ATR and TERT) also predominates, underscoring the genetic complexity of melanoma. These variants complicate clinical decision-making because their contribution to tumorigenesis, therapeutic response, and prognosis remains uncertain. Nevertheless, these variants also offer a valuable resource for future research, as they may uncover novel pathogenic mechanisms or therapeutic targets once their significance is elucidated. Integrating comprehensive genetic profiling with immunologic markers can enhance patient stratification and support rational, potentially synergistic strategies, such as combining targeted therapies with immunotherapy, to optimize clinical outcomes. This study is limited due to a small cohort and limited available clinical data. Larger cohort studies and prospective clinical trials are necessary to validate and explore the interplay between molecular and immune biomarkers as well as general biological mechanism in paving therapeutic way in melanoma. Full article

The RAS family of oncoproteins (KRAS, HRAS, and NRAS) drive aggressive cancers like pancreatic ductal adenocarcinoma (PDAC) and non-small cell lung cancer (NSCLC), yet targeting mutant RAS has historically been challenging due to its “undruggable” structure. Recent advances in mutation-specific inhibitors (e.g., sotorasib for KRAS^G12C) have demonstrated clinical efficacy but face limitations in tumor types like PDAC, where KRAS^G12C mutations are rare. Broad-spectrum pan-RAS inhibitors (e.g., RMC-7977, RMC-6236, ADT-007/ADT-1004) now offer promise by targeting active GTP-bound or nucleotide-free RAS across isoforms and mutations. Preclinical studies show these agents induce deep tumor regressions, overcome resistance to allele-specific inhibitors, and remodel the tumor microenvironment (TME) by enhancing T-cell infiltration and reducing immunosuppressive myeloid cells. Early clinical data for RMC-6236 report disease control rates of 85–87% in NSCLC and PDAC, with manageable toxicity. This review shows that pan-RAS inhibitors represent a promising new class of therapeutics capable of overcoming many historical challenges associated with the “undruggable” nature of RAS proteins and demonstrating encouraging preclinical and early clinical results, particularly in difficult-to-treat tumor types such as PDAC and NSCLC. Challenges remain in achieving a therapeutic index due to RAS’s role in normal tissue homeostasis, but tumor-specific drug accumulation and rapid normal tissue recovery may mitigate risks. Ongoing trials are evaluating combination strategies with immunotherapy and chemotherapy, positioning pan-RAS inhibitors as transformative agents for RAS-driven cancers. Full article

Background/Objectives: Melanoma is a malignant tumour of melanocytes. Cutaneous melanoma accounts for the vast majority of cases and has benefitted from advances in targeted and immune checkpoint inhibitor therapies, leading to substantial improvements in survival. In contrast, mucosal and vulvovaginal melanomas are rare, aggressive subtypes with distinct molecular and immune profiles and poor prognoses. This review synthesises evidence comparing cutaneous, mucosal, and vulvovaginal melanoma, with emphasis on biology, treatment, and outcomes Methods: A narrative comparative review was undertaken, examining the published literature on the epidemiology, molecular and immune characteristics, and treatment outcomes of cutaneous, mucosal, and vulvovaginal melanoma, including systemic therapies and surgical approaches. Results: Cutaneous melanoma demonstrates high tumour mutational burden and frequent BRAF and NRAS mutations, underpinning the success of targeted therapy and immunotherapy. Mucosal and vulvovaginal melanomas exhibit lower mutational burden, distinct mutation patterns, and reduced immunogenicity, correlating with poorer treatment responses. Surgery remains the mainstay of management, though optimal margins in vulvovaginal melanoma are unclear. Recurrence rates are high, and five-year survival remains poor. Evidence for systemic therapy is limited to small retrospective cohorts and subgroup analyses, showing lower response and survival rates compared with cutaneous melanoma. Chemotherapy has minimal benefit. Conclusions: Mucosal and vulvovaginal melanomas are biologically and clinically distinct from cutaneous melanoma and continue to have poor survival outcomes. Their rarity restricts high-quality evidence, highlighting the need for collaborative, innovative research to inform effective treatment strategies. Full article

Introduction: The aim of the study was to analyse the results and potential complications of local treatment with HDR (high dose-rate) brachytherapy of liver metastases from colorectal cancer, depending on the targeted therapy used and considering RAS gene mutation and chemotherapy in individual treatment lines. Material and methods: The study included 142 patients with oligoprogressive liver metastases who underwent HDR brachytherapy without changing the line of treatment, based on a retrospective analysis of 270 patients treated between 2015 and 2022. The impact of RAS gene mutations, lines of chemotherapy depending on the treatment regimens used, PFS (progression free survival), OS (overall survival), LC (local control) and the degree of radiological response were analysed. The impact of these drugs on hepatotoxicity and the risk of haemorrhagic complications was also analysed. Results: The presence of mutations in KRAS/NRAS genes (exons 2, 3, 4) had a statistically significant impact on PFS in the first, third and fourth lines of treatment, and on OS and LC in the third and fourth lines of treatment. In the third and fourth lines of treatment, patients with a mutation in the RAS gene had a poorer radiological response to treatment regardless of the chemotherapy used. PFS, OS and LC differed depending on the line of treatment and amounted to 17.5, 11, 8.5, 6 and 4 months, 27, 19, 13, 11 and 11 months, and 27, 19, 11, 6 and 6 months, respectively. The greatest benefit in terms of PFS was achieved by patients treated with first-line chemotherapy combined with epidermal growth factor receptor (EGFR) inhibitors, in the absence of RAS gene mutations. In the third line, the greatest benefit was achieved by patients treated with trifluridine/tipiracil in the absence of RAS gene mutations. The greatest percentage reduction in the volume of treated lesions and the highest percentage of control were observed in the first three lines of treatment. The toxicity of the treatment was low; only in the third and fourth lines of treatment were differences in the decrease in albumin levels found depending on the type of treatment used. Conclusions: A mutation in the RAS genes worsens the prognosis, regardless of the line of treatment and the systemic treatment used. The greatest benefit from brachytherapy is seen in patients in the first three lines of treatment without RAS mutations, treated with anti-EGFR chemotherapy in the first line and trifluridine/tipiracil in the third line. Combining brachytherapy of liver metastases with systemic treatment is safe, regardless of the systemic treatment used. Full article

Low-grade-serous ovarian carcinomas (LGSOC) are rare tumors characterized by a high recurrence rate and limited treatment options. Most LGSOC are estrogen receptor (ER)-positive and demonstrate alterations in the RAS/MAPK pathway. Avutometinib is a dual RAF/MEK clamp, whereas defactinib and VS-4718 are focal adhesion kinase (FAK) inhibitors. Fulvestrant is an ER antagonist/degrader. We assessed the preclinical efficacy of fulvestrant, avutometinib + VS-4718 (FAKi), and the triple combination in a chemotherapy/aromatase inhibitor-resistant LGSOC patient-derived tumor xenograft (PDX) model. Tissue obtained from a LGSOC patient wild-type for KRAS/NRAS/BRAF mutations in progression after chemotherapy/anastrozole was transplanted into female CB17/lcrHsd-Prkdc/SCID mice (PDX-OVA(K)250). The animals were treated with either saline/control, fulvestrant, avutometinib/FAKi, or the triple combination of avutometinib/FAKi/fulvestrant. Avutometinib and FAKi were given five-days on and two-days off through oral gavage. Fulvestrant was administered subcutaneously weekly. Mechanistic studies were performed ex vivo using Western blot assays. Animals treated with the triple combination demonstrated stronger tumor growth inhibition compared to all the other experimental groups including control/saline (p < 0.001), single-agent fulvestrant (p = 0.04 from day eight and onwards), and avutometinib/FAKi (p = 0.02 from day 18). Median survival for mice treated with saline/control was 29 days while mice in all other experimental groups were alive at day 60 (p < 0.0001). Treatment was well tolerated across all experimental treatments. By Western blot, exposure of OVA(K)250 to the triple combination demonstrated a decrease in phosphorylated MEK (p-MEK) and p-ERK levels. The addition of fulvestrant to avutometinib/FAKi is well tolerated in vivo and enhances the antitumor activity of avutometinib/FAKi in a LGSOC-PDX model with acquired resistance to chemotherapy/aromatase inhibitors. These results support the clinical evaluation of avutometinib/defactinib in combination with fulvestrant or an aromatase inhibitor in patients with recurrent LGSOC. Full article

Colorectal cancer (CRC) remains a leading cause of cancer-related mortality globally, posing significant treatment challenges, particularly in its metastatic form (mCRC). This review comprehensively examines the pivotal role of RAS mutations, specifically KRAS and NRAS, which are detected in approximately 40–45% of mCRC cases, and their impact on treatment decisions and patient outcomes. We assess the effectiveness of standard treatments within the RAS mutant population, highlighting the challenges and limitations these therapies face. Recent advancements in targeted therapies, particularly the focus on novel agents such as KRAS G12C inhibitors, including sotorasib and adagrasib, have shown promising efficacy in overcoming resistance to conventional treatments. Furthermore, this review discusses future directions, emphasizing the need for research into non-RAS targets to address the complexities of resistance mechanisms and improve therapeutic outcomes. This review aims to provide a detailed overview of the current treatments and innovative approaches, supporting the development of personalized management strategies for patients with mCRC. Full article

Background: Canine oral melanoma (COM) is an aggressive and often fatal neoplasm in dogs, with clinical and molecular similarities to human melanoma. Despite its relevance as a comparative oncology model, the molecular mechanisms underlying COM remain poorly understood. This study aimed to characterize gene expression profiles in COM to identify differentially expressed genes (DEGs), potential biomarkers, and therapeutic targets. Methods: In this pilot study, we performed RNA sequencing (RNA-seq) on tumor and healthy oral tissue samples from dogs. Two independent analytical pipelines—Bowtie2-DESeq2 and HISAT-StringTie-Ballgown—were used to ensure robustness in DEG detection. We also conducted pathway enrichment and isoform-level analyses to investigate biological processes and alternative splicing events. Results: Both approaches identified a core set of 929 common DEGs. Key oncogenic pathways, including MAPK/ERK and cell cycle regulation, were significantly affected, with notable upregulation of BRAF, NRAS, CDK4, and MITF (log2FC = 2.86, p < 0.001). The transcription factor SOX10 and the cytokine IL-33, both previously implicated in melanoma progression, were consistently overexpressed. Additionally, NF1, a known RAS pathway inhibitor, was also upregulated. Isoform analysis revealed novel transcript variants, suggesting a complex layer of post-transcriptional regulation in COM. Many DEGs remained uncharacterized, and chromosomal distribution analysis highlighted potential genomic influences. Conclusions: Our findings provide new insights into the molecular landscape of COM, reinforcing its utility as a model for human melanoma. The identification of conserved oncogenic pathways and novel transcript variants opens avenues for further functional studies and the development of targeted therapies in both veterinary and human oncology. Full article

NRAS-mutant melanoma represents a clinically challenging subset of melanoma with limited effective therapies and intrinsic resistance to targeted MEK inhibition. Recent findings highlight protein S-nitrosylation, a redox-dependent post-translational modification as a critical modulator of MEK-ERK signaling and immune evasion in this context. In this commentary, we discuss how S-nitrosylation of MAPK components, including MEK and ERK, sustains oncogenic signaling and attenuates immunogenic cell death. Targeting this modification with nitric oxide synthase (NOS) inhibitors such as L-NAME, L-NMMA and 1400w restore sensitivity of MEK inhibitor, promotes dendritic cell activation, and enhances CD8+ T cell infiltration in preclinical models such as immunogenic mouse models and individual patient derived, primary melanoma cells. We also explore the emerging role of S-nitrosylation in regulating macrophage-mediated immune surveillance and propose translational strategies for combining redox modulation with targeted and immune therapies. These insights offer a compelling framework for overcoming therapeutic resistance and reprogramming the tumor immune microenvironment to activate the cytotoxic T-cells and enhance the responses to immunotherapy in NRAS-driven cancers. Full article

Acute myeloid leukemia (AML) has traditionally been linked to a poor prognosis, particularly in older patients who are ineligible for intensive chemotherapy. The advent of Venetoclax, a powerful oral BH3 mimetic targeting anti-apoptotic protein BCL2, has significantly advanced AML treatment. Its combination with the hypomethylating agent azacitidine (AZA/VEN) has become a standard treatment for this group of AML patients, demonstrating a 65% overall response rate and a median overall survival of 14.7 months, compared to 22% and 8 months with azacitidine monotherapy, respectively. However, resistance and relapses remain common, representing a significant clinical challenge. Recent studies have identified molecular alterations, such as mutations in FLT3-ITD, NRAS/KRAS, TP53, and BAX, as major drivers of resistance. Additionally, other factors, including metabolic changes, anti-apoptotic protein expression, and monocytic or erythroid/megakaryocytic differentiation status, contribute to treatment failure. Clinical trials are exploring strategies to overcome venetoclax resistance, including doublet or triplet therapies targeting IDH and FLT3 mutations; novel epigenetic approaches; menin, XPO1, and MDM2 inhibitors; along with immunotherapies like monoclonal antibodies and antibody–drug conjugates. A deeper understanding of the molecular mechanisms of resistance through single-cell analysis will be crucial for developing future therapeutic strategies. Full article

Background/Objectives: Acute myeloid leukemia (AML) is a rare hematological malignancy with a poor prognosis. Activating c-Kit (CD117) mutations occur in 5% of de novo AML and 30% of core-binding factor (CBF) AML, leading to worse clinical outcomes. Posttranslational modifications, particularly with myristic and palmitic acid, are crucial for various cellular processes, including membrane organization, signal transduction, and apoptosis regulation. However, most research has focused on solid tumors, with limited understanding of these mechanisms in AML. Fatty acid synthase (FASN), a key palmitoyl-acyltransferase, regulates the subcellular localization, trafficking, and degradation of target proteins, such as H-Ras, N-Ras, and FLT3-ITDmut receptors in AML. Methods: In this study, we investigated the role of FASN in two c-Kit-N822K-mutated AML cell lines using FASN knockdown via shRNA and the FASN inhibitor TVB-3166. Functional implications, including cell proliferation, were assessed through Western blotting, mass spectrometry, and PamGene. Results: FASN inhibition led to an increased phosphorylation of c-Kit (p-c-Kit), Lyn kinase (pLyn), MAP kinase (pMAPK), and S6 kinase (pS6). Furthermore, we observed sustained high expression of Gli1 in Kasumi1 cells following FASN inhibition, which is well known to be mediated by the upregulation of pS6. Conclusions: The combination of TVB-3166 and the Gli inhibitor GANT61 resulted in a significant reduction in the survival of Kasumi1 cells. Full article

Malignant melanoma is a lethal skin cancer containing melanoma-initiating cells (MICs), implicated in tumorigenesis, invasion, and drug resistance, and characterized by an elevated expression of stem cell markers, including CD133. siRNA knockdown of CD133 has been previously shown to enhance apoptosis induced by the MEK inhibitor trametinib in melanoma cells. This study investigates the underlying mechanisms of CD133’s anti-apoptotic activity in patient-derived BAKP melanoma, harboring the difficult-to-treat NRAS^Q61K driver mutation, after CRISPR-Cas9 CD133 knockout or Doxycycline (Dox)-inducible re-expression of CD133. CD133 knockout in BAKP cells increased trametinib-induced apoptosis by reducing anti-apoptotic p-AKT and p-BAD and increasing pro-apoptotic BAX. Conversely, Dox-induced CD133 expression diminished apoptosis in trametinib-treated cells, coincident with elevated p-AKT, p-BAD, and decreased activation of BAX and caspase-3. However, trametinib in combination with pan-AKT inhibitor capivasertib reduced cell survival as measured by XTT viability assays and apoptosis and colony formation assays, independent of CD133 status. CD133 may therefore activate a survival pathway wherein (1) increased AKT phosphorylation and activation induces (2) BAD phosphorylation and inactivation, which (3) decreases BAX activation, and (4) reduces caspases-3 activity and caspase-mediated PARP cleavage, leading to apoptosis suppression and drug resistance in melanoma. In vivo mouse xenograft studies using Dox-inducible melanoma cells revealed increased rates of tumor growth after induction of CD133 expression in trametinib-treated +Dox mice, an effect which was synergistically suppressed by combination treatment. Targeting nodes of the AKT and MAPK survival pathways with trametinib and capivasertib highlights the potential for combination therapies for NRAS-mutant melanoma stem cells for the development of more effective treatments for patients with high-risk melanoma. Full article

The expression level of Programmed Death-Ligand 1 (PD-L1) determined by the immunohistochemical method is currently approved to test the potential efficacy of immune-checkpoint inhibitors and to candidate patients with Non-Small Cell Lung Cancer (NSCLC) for treatment with immunotherapeutic drugs. As part of the CORELAB (New prediCtivebiOmaRkers of activity and Efficacy of immune checkpoint inhibitors in advanced non-small cell Lung cArcinoma) project, aimed at identifying new predictive and prognostic biomarkers in NSCLC patients receiving immunotherapeutic drugs, we investigated the role of circulating tumor DNA (ctDNA) molecular characterization as an additional predictive biomarker. We analyzed plasma ctDNA by targeted Next Generation Sequencing in a subset of 50 patients at different time points. ctDNA content was inversely correlated with the clinical outcome both at a baseline and after 2 months of treatment. OS was significantly higher in patients with ≥50% ctDNA reduction. TP53 and KRAS were the most frequently mutated genes, and patients with KRAS and/or TP53 mutations showed worse outcomes than patients without detectable variants or with mutations in other genes. Fewer common variants were found in BRAF, EGFR, MAP2K1, MET, NRAS, and PIK3CA genes. Our data demonstrated that molecular characterization of ctDNA and also its quantitative evaluation could serve as a dynamic, real-time prognostic, and predictive biomarker, enabling regular molecular monitoring of therapy efficacy in support of other medical examinations. Full article

Background: There are no active treatment options for patients with progressive melanoma brain metastases (MBM) failing immune checkpoint blockade (ICB) and BRAF/MEK inhibitors (BRAF/MEKi). Regorafenib (REGO), an oral multi-kinase inhibitor (incl. RAF-dimer inhibition), can overcome adaptive resistance to BRAF/MEKi in preclinical models. Methods: This is a single-center retrospective case series of patients with refractory MBM treated with REGO plus BRAF/MEKi (compassionate use). Results: A total of 22 patients were identified (18 BRAF-mutant, 4 NRAS^Q61-mutant; 19 with progressive MBM; 11 on corticosteroids). Thirteen BRAF^V600-mutant patients were progressing on BRAF/MEKi at the time of REGO association. BRAF-mutant patients received REGO (40–80 mg once daily) combined with BRAF/MEKi, NRAS-mutant patients were treated with REGO + MEKi (+low-dose BRAFi to mitigate skin-toxicity). Grade 3 TRAE included arterial hypertension (n = 4) and maculopapular rash (n = 3). There were no G4/5 TRAE. In BRAF-mutant patients, overall and intracranial objective response rates (overall ORR and IC-ORR) were 11 and 29%, and overall and intracranial disease control rates (overall DCR and IC-DCR) were 44 and 59%, respectively. In NRAS-mutant patients overall ORR and IC-ORR were 0 and 25% and overall DCR and IC-DCR were 25 and 50%, respectively. The median PFS and OS were, respectively, 7.1 and 16.4 weeks in BRAF-mutant and 8.6 and 10.1 weeks in NRAS-mutant patients. Conclusions: In heavily pretreated patients with refractory MBM, REGO combined with BRAF/MEKi demonstrated promising anti-tumor activity with an acceptable safety profile. In BRAF^V600-mutant melanoma patients, responses cannot solely be attributed to BRAF/MEKi rechallenge. Further investigation in a prospective trial is ongoing to increase understanding of the efficacy. Full article

Colorectal cancer (CRC) arises through a combination of genetic and epigenetic alterations that affect key pathways involved in tumor growth and progression. This review examines the major molecular pathways driving CRC, including Chromosomal Instability (CIN), Microsatellite Instability (MSI), and the CpG Island Methylator Phenotype (CIMP). Key mutations in genes such as APC, KRAS, NRAS, BRAF, and TP53 activate signaling pathways like Wnt, EGFR, and PI3K/AKT, contributing to tumorigenesis and influencing responses to targeted therapies. Resistance mechanisms, including mutations that bypass drug action, remain challenging in CRC treatment. This review highlights the role of molecular profiling in guiding the use of targeted therapies such as tyrosine kinase inhibitors and immune checkpoint inhibitors. Novel combination treatments are also discussed as strategies to improve outcomes and overcome resistance. Understanding these molecular mechanisms is critical to advancing personalized treatment approaches in CRC and improving patient prognosis. Full article

Amelanotic melanoma (AM) is a subtype of hypomelanotic or completely amelanotic melanoma. AM is a rare subtype of melanoma that exhibits a higher recurrence rate and aggressiveness as well as worse surveillance than typical melanoma. AM shows a dysregulation of melanin production, cell cycle control, and apoptosis pathways. Knowing these pathways has an application in medicine due to targeted therapies based on the inhibiting elements of the abovementioned pathways. Therefore, we summarized and discussed AM biochemical and molecular induction pathways and personalized medicine approaches, clinical management, and future directions due to the fact that AM is relatively rare. AM is commonly misdiagnosed. Hence, the role of biomarkers is becoming significant. Nonetheless, there is a shortage of biomarkers specific to AM. BRAF, NRAS, and c-KIT genes are the main targets of therapy. However, the role of BRAF and KIT in AM varied among studies. BRAF inhibitors combined with MAK inhibitors demonstrate better results. Immune checkpoint inhibitors targeting CTLA-4 combined with a programmed death receptor 1 (PD-1) show better outcomes than separately. Fecal microbiota transplantation may overcome resistance to immune checkpoint therapy of AM. Immune-modulatory vaccines against indoleamine 2,3-dioxygenase (IDO) and PD ligand (PD-L1) combined with nivolumab may be efficient in melanoma treatment. Full article