Murine Sarcoma Viral Oncogene Homolog Research Articles

Bilateral Pterygium in a Paediatric Cancer Patient taking Vemurafenib: A Case Report

Introduction: Anticancer drugs with reactive oxygen species (ROS) inducing mechanisms, such as vemurafenib, have been shown to be effective against various types of cancer. However, the adverse effects of increased oxidative stress have the potential to damage not only cancer cells, but also normal cells such as those in eyes and potentially leading to ocular diseases including pterygium and cataract. Presentations: A nine-year-old patient presented with bilateral nasal pterygium and early bilateral cortical cataracts, which are uncommon for his age group. Patient has a background of v-raf murine sarcoma viral oncogene homolog B1 (BRAF) V600E positive pilocytic astrocytoma with anaplastic features, diagnosed at age 2.5 years old. Vemurafenib was commenced at the time of diagnosis. Conclusion: We suspect that these ophthalmic findings are associated with his prolonged treatment with vemurafenib which may be of a pathophysiological significance.

Association Between Gross Features and Coexistence of BRAFV600E and TERT Promoter Mutations in Papillary Thyroid Carcinomas: A Combined Analysis Incorporating Clinicopathologic Features.

Background: The coexistence of v-Raf murine sarcoma viral oncogene homolog B1 (BRAFV600E) and telomere reverse transcriptase promoter (TERT-p) mutations is considerably associated with aggressiveness and poor prognosis in papillary thyroid carcinoma (PTC). However, the association between gross findings and genetic alterations in PTC remains unknown. We aimed to investigate the association between clinicopathologic features, including macroscopic features, and the coexistent BRAFV600E and TERT-p mutations in patients with PTC. Methods: We retrospectively analyzed 375 cases of PTC surgically resected between January 2018 and October 2023 at a single institution, based on the presence of BRAFV600E and TERT-p double mutation. Clinicopathologic features, including gross features on the cut surface of tumors, were evaluated. Subsequently, the association between clinicopathologic features and mutation status was statistically examined. Cox proportional hazard models were used to analyze the impact of molecular pathological features on disease-free survival (DFS). Results: The BRAFV600E and TERT-p double mutation was identified in 78 (20.8%) patients among the PTC cases and was significantly correlated with shorter DFS. Multivariable analysis revealed that factors such as relatively older age (≥55 years) (odds ratio [OR] = 12.083, 95% confidence interval [CI] 4.498-32.456), larger tumor size (>2.0 cm) (OR = 2.722, CI 1.104-6.712), lobulated tumor margins (OR = 16.114, CI 3.155-82.296), papillary excrescences on the cut surface (OR = 17.573, CI 3.462-89.201), solid-cut surface (OR = 4.012, CI 1.084-14.849), minimal extrathyroidal extension (ETE) (OR = 4.156, CI 1.209-14.282), gross ETE (OR = 6.517, CI 1.734-24.490), and Ki-67 labeling index (LI) (≥5%, OR = 12.145, CI 4.354-33.877) were significantly associated with the double mutation. Conclusions: The BRAFV600E and TERT-p double mutation in PTC was significantly associated with relatively old age, larger tumor size, lobulated configuration in tumor margin, papillary excrescences on the cut surface, solid-cut surface, ETE, and high Ki-67 LI. These features are suggestive of the presence of the double mutation and should be analyzed at the molecular level in patients with PTC.

Update on the treatment of BRAFmut metastatic melanoma and future perspectives

Abstractv‐Raf murine sarcoma viral oncogene homolog B (BRAF) mutations were first identified in melanoma in 2002, leading to increased cell division and proliferation, and resultant tumour growth. The identification and characterisation of BRAF mutations (BRAFmut) led to the development of several highly specific, BRAF‐, then mitogen‐activated kinase enzyme (MEK)‐targeted therapies that have enabled rapid tumour responses and improved treatment outcomes in most patients with metastatic BRAFmut melanoma. The combination of these two drug classes (BRAF inhibitors and MEK inhibitors) has demonstrated improved response rates, progression‐free survival, and overall survival (OS), along with a more tolerable safety profile, compared with BRAF inhibition alone. In parallel, improved knowledge of the immune system has enabled the development of immune checkpoint inhibitors (ICIs), although immune‐related adverse events with ICIs may prove to be problematic in some patients and require careful management. While targeted therapy appears to provide rapid disease control in a relatively high proportion of patients, the development of secondary resistance may limit the overall duration of responses. Acquired resistance, along with primary resistance, has also been reported for ICIs, with a lower overall response rate to that with targeted therapy, although durable responses have been reported in some responding patients. A combination strategy of targeted therapy with ICIs has demonstrated modest increases in efficacy compared with targeted therapy combinations, although data significance varies across studies, there is increased risk of toxicity, and triple combination therapy has not yet received clinical approval in Europe. Thus, there is an ongoing need to establish optimal sequencing of these treatments in patients with advanced BRAFmut melanoma, and this has become the focus of current research. The aim of this narrative review was to provide an update on the treatment of BRAFmut metastatic melanoma, current guideline recommendations, and future clinical perspectives.

Identification of CDH4 Gene Copy Number Alteration and Its Association with Clinical Profile of Colorectal Cancer Patient

Background: The genes cadherin 4 (CDH4), Kirsten rat sarcoma viral oncogene homolog (KRAS), V-Raf murine sarcoma viral oncogene homolog B (BRAF), and microsatellite instability (MSI) each play a role in the development of colorectal cancer (CRC). CDH4 gene is located in chromosome 20q13.33 and its amplification or gain is the earliest mutational event found in the majority of CRC and colon polyps. This study aimed to identify copy number alteration in the CDH4 gene and its association with the clinical profile of CRC patients, including gender, age, tumor location and differentiation, frequency of BRAF and KRAS mutations, and MSI status. Methods: The DNA was extracted from 50 tumors and adjacent normal tissues based on the manufacturer’s instructions. Detection of MSI status was carried out by pentaplex polymerase chain reaction (PCR) and PCR products were size separated by capillary electrophoresis (CE) using an ABI 310 Genetic Analyzer. Both KRAS and BRAF mutations were identified by PCR and sequencing while CDH4 copy measurement was measured using TaqManTM Copy Number Assay. Results: Our findings showed 22 (44%) samples with no changes in the copy number of CDH4 gene. Interestingly, 21 (42%) cases had an amplification of the CDH4 gene or CDH4 gene gain, and seven (14%) cases decreased in CDH4 gene expression or CDH4 gene loss. We found an association between changes in the CDH4 gene and gender (p=0.001). However, there was no association between changes in the CDH4 gene and age (p=0.979), tumor location (p=0.145) and differentiation (p=0.648), the frequency of BRAF (p=0.171) and KRAS mutations (p=0.184) and MSI status (p=0.923). Conclusions: Copy number alteration in CDH4 gene in CRC patients and this alteration is significantly associated with gender. Further studies with a larger number of samples are essential to confirm this result and to identify the cause of CDH4 copy number alteration and its biological significance.

Clinicopathological features, response patterns, outcomes and BRAF status in patients with advanced acral melanoma: a preliminary Peruvian study.

Globally, acral melanoma (AM) is underrepresented in most clinical trials, being predominant in Caucasian populations. Latin America is a niche that needs to be explored. Therefore, this study aimed to determine the clinical features, response patterns, outcomes and v-raf murine sarcoma viral oncogene homolog B1 (BRAF) status in Peruvian patients with advanced AM. We retrospectively reviewed the medical records of 19 patients with advanced AM who received immunotherapy (IO) in first- or subsequent-line therapy. The samples were analysed, and their mutational state was performed by deoxyribonucleic acid sequencing, focusing primarily on the most frequently mutated gene, BRAF. Descriptive statistics were used to assess the baseline characteristics. Overall survival was estimated using the Kaplan-Meier method. The median age was 64 years and 63.2% were men. Plantar was the site most frequently affected (84.2%). The most frequent stage was stage III (68.4%), with 26.4% receiving adjuvant therapy. The majority of cases exhibited a Breslow thickness of >4 mm (52%), a Clark level of IV/V (89.4%), and all patients presented ulceration and a high range of mitosis. During follow-up, all patients experienced recurrent advanced disease, with 52.6% developing visceral metastasis. Patients who received IO as first or subsequent line had an overall response rate (ORR) of 33.3%, and those who received it as first-line therapy had an ORR of 40%. Twenty-one percent of the patients harbored BRAF V6000E mutation and, showing an ORR of 50% compared to wild-type individuals (44.4%) after the first line of treatment. Our preliminary study reported that AM has poor clinico-pathological features and response rates to IO in Peruvian patients. However, those who received IO as a first-line treatment or harbored the BRAF mutation appeared to have a slightly better response than wild-type patients.

Characterization of two melanoma cell lines resistant to BRAF/MEK inhibitors (vemurafenib and cobimetinib)

BackgroundBRAF (v-raf murine sarcoma viral oncogene homolog B1)/MEK (mitogen-activated protein kinase kinase) inhibitors are used for melanoma treatment. Unfortunately, patients treated with this combined therapy develop resistance to treatment quite quickly, but the mechanisms underlying this phenomenon are not yet fully understood. Here, we report and characterize two melanoma cell lines (WM9 and Hs294T) resistant to BRAF (vemurafenib) and MEK (cobimetinib) inhibitors.MethodsCell viability was assessed via the XTT test. The level of selected proteins as well as activation of signaling pathways were evaluated using Western blotting. The expression of the chosen genes was assessed by RT-PCR. The distribution of cell cycle phases was analyzed by flow cytometry, and confocal microscopy was used to take photos of spheroids. The composition of cytokines secreted by cells was determined using a human cytokine array.ResultsThe resistant cells had increased survival and activation of ERK kinase in the presence of BRAF/MEK inhibitors. The IC50 values for these cells were over 1000 times higher than for controls. Resistant cells also exhibited elevated activation of AKT, p38, and JNK signaling pathways with increased expression of EGFR, ErbB2, MET, and PDGFRβ receptors as well as reduced expression of ErbB3 receptor. Furthermore, these cells demonstrated increased expression of genes encoding proteins involved in drug transport and metabolism. Resistant cells also exhibited features of epithelial-mesenchymal transition and cancer stem cells as well as reduced proliferation rate and elevated cytokine secretion.ConclusionsIn summary, this work describes BRAF/MEK-inhibitor-resistant melanoma cells, allowing for better understanding the underlying mechanisms of resistance. The results may thus contribute to the development of new, more effective therapeutic strategies.

Gene mutation characteristics of clinical stage ⅠA lung adenocarcinoma and their relations with patients' long-term prognosis

Objective: To explore the gene mutation characteristics and the relationship between gene mutations and long-term prognosis in clinical stage ⅠA lung adenocarcinoma patients. Methods: A retrospective analysis was conducted on 63 clinical stage ⅠA lung adenocarcinoma patients who underwent surgical resection at the Cancer Hospital of the Chinese Academy of Medical Sciences from January 2007 to October 2012, with documented postoperative recurrence or metastasis, as well as those who had a follow-up duration of 10 years or more without recurrence or metastasis. Whole exome sequencing (WES) technology was used to analyze the gene mutation profiles in tumor tissues and univariate and multivariate Cox regression analysis were used to clarify the influencing factors for patient prognosis. Results: After long term follow-up, 13 out of the 63 patients (21%) experienced recurrence or metastasis. WES technology analysis revealed that the most common tumor related gene mutations occurred in epidermal growth factor receptor (EGFR), with a mutation rate of 65.1% (41/63), followed by tumor protein p53 (TP53), fatatypical cadherin 1 (FAT1), low density lipoprotein receptor-related protein 1B (LRP1B), mechanistic target of rapamycin (MTOR), phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit gamma (PIK3CG), and SWI/SNF related, matrix associated, actin dependent regulator of chromatin, subfamily A, member 4 (SMARCA4), with mutation rates of 30.2% (19/63), 20.6% (13/63), 15.9% (10/63), 15.9% (10/63), 15.9% (10/63), and 15.9% (10/63), respectively. Multivariate Cox regression analysis showed that PIK3CG mutations (HR=21.52, 95% CI: 3.19-145.01),smoothened (SMO) mutations (HR=35.28, 95% CI: 3.12-398.39), catenin beta 1 (CTNNB1) mutations (HR=332.86, 95% CI: 15.76-7 029.05), colony stimulating factor 1 receptor (CSF1R) mutations (HR=8 109.60, 95% CI: 114.19-575 955.17), and v-Raf murine sarcoma viral oncogene homolog B (BRAF) mutations (HR=23.65, 95% CI: 1.86-300.43) were independent risk factors affecting the prognosis of clinical stage ⅠA lung adenocarcinoma patients. Conclusions: PIK3CG, SMO, CTNNB1, CSF1R, BRAF gene mutations are closely related to long-term recurrence or metastasis in clinical stage ⅠA lung adenocarcinoma. Patients with these gene mutations should be given closer clinical attention.

CDK4/6 inhibition to resensitize BRAF/EGFR inhibitor in patient-derived BRAF/PTEN-mutant colon cancer cells.

In v-raf murine sarcoma viral oncogene homolog B1 (BRAF)-mutant colorectal cancer (CRC), encorafenib-cetuximab has been established as standard second-line therapy, but not all patients respond and the duration of response is relatively short. Overcoming intrinsic or acquired resistance to BRAF/EGFR inhibitors is crucial for enhancing treatment outcomes in metastatic BRAF-mutated CRC. The aim of the study is to investigate the resistance mechanisms in BRAF-mutant CRC patient refractory to BRAF/EGFR targeted therapy. We established patient-derived cells (PDCs) from a patient with BRAF/PTEN-mutant metastatic colon cancer who progressed rapidly on encorafenib plus cetuximab. To explore potential treatment options for inherent resistance caused by simultaneous PTEN mutation in BRAF-mutated CRC, we conducted cell viability assays using PDCs treated with encorafenib-cetuximab in combination with a cyclin-dependent kinase-4 and 6 (CDK4/6) inhibitor. The patient's tumor had concurrent PTEN loss-of-function alteration at diagnosis and PDCs were generated from ascites after resistance to the BRAF/EGFR inhibitor. The PDCs were resistant to the encorafenib-cetuximab combination even at a high concentration of cetuximab (up to 500 µg/mL). Adding the CDK4/6 inhibitor, ribociclib, to encorafenib-cetuximab showed a synergistic effect in a proliferation assay. Ribociclib plus encorafenib-cetuximab represented a significantly lower expression of Ki-67 compared to the dual combination alone. An MTS assay showed that triplet therapy with ribociclib, encorafenib, and cetuximab suppressed cell viability more efficiently than the two-drug combinations. Investigating the combined effect of triplet therapy using the calculated combination index (CI) showed that ribociclib had a synergistic effect with encorafenib-cetuximab when applied to PDCs with a concurrent BRAF/PTEN mutation. Our results suggest that combining the CDK4/6 inhibitor with the BRAF/EGFR inhibitormight be a novel treatment strategy for concomitant BRAF and PTEN-mutant CRC.

Exosomal miR-19a derived from melanoma cell promotes the vemurafenib resistance of malignant melanoma through directly targeting LRIG1 to reactivate AKT and MAPK pathway

Exosomes derived from neighboring v-raf murine sarcoma viral oncogene homolog B1 inhibitor (BRAFi)-resistant melanoma cells mediate the formation of resistance in melanoma cells sensitive to BRAFi. The function and molecular mechanisms of exosomal miRNA in BRAFi resistance of melanoma have not been studied. We found that the expression of miR-19a in BRAFi resistant melanoma cells was significantly higher than that in sensitive cells, and miR-19a contributes to the resistance of melanoma cells to BRAFi by targeting immunoglobulin-like domains protein 1 (LRIG1). miR-19a was highly enriched in exosomes secreted from BRAFi resistant melanoma cells, and these exosomal miR-19a promote the spread of BRAFi resistant. The reactivation of Protein kinase B (AKT) and mitogen-activated protein kinase (MAPK) pathways is the main reason for the BRAFi resistant of melanoma cells. We demonstrated that exosomal miR-19a derived from melanoma cell promotes the formation and spread of BRAFi resistant in melanoma through targeting LRIG1 to reactivate AKT and MAPK pathway. Therefore, miR-19a may serve as a potential therapeutic target in melanoma patients with acquired drug resistance.

Structure-Based De Novo Design for the Discovery of Miniprotein Inhibitors Targeting Oncogenic Mutant BRAF.

Being a component of the Ras/Raf/MEK/ERK signaling pathway crucial for cellular responses, the VRAF murine sarcoma viral oncogene homologue B1 (BRAF) kinase has emerged as a promising target for anticancer drug discovery due to oncogenic mutations that lead to pathway hyperactivation. Despite the discovery of several small-molecule BRAF kinase inhibitors targeting oncogenic mutants, their clinical utility has been limited by challenges such as off-target effects and suboptimal pharmacological properties. This study focuses on identifying miniprotein inhibitors for the oncogenic V600E mutant BRAF, leveraging their potential as versatile drug candidates. Using a structure-based de novo design approach based on binding affinity to V600E mutant BRAF and hydration energy, 39 candidate miniprotein inhibitors comprising three helices and 69 amino acids were generated from the substructure of the endogenous ligand protein (14-3-3). Through in vitro binding and kinase inhibition assays, two miniproteins (63 and 76) were discovered as novel inhibitors of V600E mutant BRAF with low-micromolar activity, with miniprotein 76 demonstrating a specific impediment to MEK1 phosphorylation in mammalian cells. These findings highlight miniprotein 76 as a potential lead compound for developing new cancer therapeutics, and the structural features contributing to its biochemical potency against V600E mutant BRAF are discussed in detail.

Genomic medicine advances for brain tumors.

Cancer genome profiling has revealed important genetic alterations that serve as prognostic indicators and guides for treatment decisions, enabling precision medicine. The shift to molecular diagnosis of brain tumors, as reflected in the 2021 World Health Organization Classification of Tumors of the Central Nervous System, is a crucial role for treatment decision-making. This review discusses the significance and role of cancer genome profiling in precision medicine for malignant brain tumors, particularly gliomas. Furthermore, we explore the progress in cancer genome analysis, focusing on cancer gene panel testing, integration of genomic information in brain tumor classification, and hereditary tumors. Additionally, we discuss the transformative effect of genomic medicine on early detection, risk assessment, and precision medicine strategies. The tumor mutational burden in brain tumors is considered low, but the application of molecular targeted drugs, such as isocitrate dehydrogenase inhibitors, v-raf murine sarcoma viral oncogene homolog B1 inhibitors, fibroblast growth factor receptor inhibitors, neurotrophic tyrosine receptor kinase, mechanistic target of rapamycin inhibitors, and anti-programmed death receptor-1 antibody drugs are promising for glioma treatment. We also discuss the future prospects of molecular targeted drugs.

Analysis of Body Mass Index and Clinicopathological Factors in Patients with Papillary Thyroid Carcinoma.

To analyze the correlation between body mass index (BMI) and clinicopathological factors of papillary thyroid cancer (PTC). The clinical data of patients with PCT who were hospitalized in the Department of Thyroid Surgery of the Affiliated Hospital of Guizhou Medical University from March 2023 to September 2023 were retrospectively collected, including age, gender, height, weight, BMI, v-raf murine sarcoma viral oncogene homolog B (BRAF) gene mutation, tumor size, multifocus, Hashimoto's thyroiditis, lymph node metastasis and other clinicopathological factors. According to the World Health Organization (WHO) definition for Asian population, BMI≥25kg/m2 was obese group, 23≤BMI≤24.9kg/m2 was overweight group, 18.5≤BMI≤22.9kg/m2 was normal weight group, and BMI≤18.5kg/m2 was low weight group. The clinicopathological factors of overweight and obese patients with PTC were analyzed. A total of 164 PTC patients were included, with an average BMI of (24.44±3.57) kg/m2. Age of overweight and obese PTC patients (Z=1.978, p=0.083); Gender of overweight and obese PTC patients (χ2 value: 11.570, p=0.004); Tumor size in overweight and obese PTC patients (Z=0.894, p=0.411); BRAF gene mutation in overweight and obese PTC patients (χ2 value: 1.452, p =0.623); Multifocal lesions were found in overweight and obese patients (χ2 value: 1.653, p =0.201). Hashimoto's thyroiditis was found in overweight and obese PTC patients (χ2 value: 1.147, p=0.298). Overweight and obese patients with PTC had lymph node metastasis (χ2 value: 1.690, p =0.251). Overweight and obesity in PTC patients are correlated with male, but not with age, tumor size, BRAF mutation, multifocality, Hashimoto's thyroiditis and lymph node metastasis.

RAF and MEK Inhibitors in Non-Small Cell Lung Cancer.

Lung cancer, despite recent advancements in survival rates, represents a significant global health burden. Non-small cell lung cancer (NSCLC), the most prevalent type, is driven largely by activating mutations in Kirsten rat sarcoma viral oncogene homologue (KRAS) and receptor tyrosine kinases (RTKs), and less in v-RAF murine sarcoma viral oncogene homolog B (BRAF) and mitogen-activated protein-kinase kinase (MEK), all key components of the RTK-RAS-mitogen-activated protein kinase (MAPK) pathway. Learning from melanoma, the identification of BRAFV600E substitution in NSCLC provided the rationale for the investigation of RAF and MEK inhibition as a therapeutic strategy. The regulatory approval of two RAF-MEK inhibitor combinations, dabrafenib-trametinib, in 2017, and encorafenib-binimetinib, in 2023, signifies a breakthrough for the management of BRAFV600E-mutant NSCLC patients. However, the almost universal emergence of acquired resistance limits their clinical benefit. New RAF and MEK inhibitors, with distinct biochemical characteristics, are in preclinical and clinical development. In this review, we aim to provide valuable insights into the current state of RAF and MEK inhibition in the management of NSCLC, fostering a deeper understanding of the potential impact on patient outcomes.

Tumor-targeted therapy with BRAF-inhibitor recruits activated dendritic cells to promote tumor immunity in melanoma

BackgroundTumor-targeted therapy causes impressive tumor regression, but the emergence of resistance limits long-term survival benefits in patients. Little information is available on the role of the myeloid cell network, especially...

Detection and Significance of Molecular Markers in Immunotherapy and Targeted Therapy of Colorectal Cancer in Tibet

Objective To study the expression of SWI/SNF-related,matrix-associated,actin-dependent regulator of chromatin,subfamily A,member 4(SMARCA4)/Brahma-related gene 1,V-raf murine sarcoma viral oncogene homolog B(BRAF),P53,programmed cell death protein-1(PD-1),and programmed death-ligand 1(PD-L1),and changes in the expression of BRAF and neurotrophic tyrosine receptor kinase(NTRK) in the patients with colorectal cancer in Tibet,thereby providing a basis for targeted therapy and immunotherapy for this disease in Tibet. Methods A total of 64 patients with colorectal cancer resected in the Tibet Autonomous Region People's Hospital from January 2015 to July 2021 were enrolled in this study.The expression of SMARCA4,BRAF,P53,PD-1,and PD-L1 was detected by immunohistochemical staining.The gene fusion involving NTRK1,NTRK2,and NTRK3 was detected by fluorescence in situ hybridization,and the BRAF V600E gene mutation by polymerase chain reaction. Results The 64 patients with colorectal cancer were at a male-to-female ratio of 1.21∶1,with the mean age of (56.59±13.27) years.The tumors were located in the colon in 46(71.88%) patients and in the rectum in 18(28.12%) patients.Sixty(93.75%) patients presented adenocarcinoma,and 4(6.25%) patients presented other types of tumors.The patients in T1/T2 and T3/T4 phases accounted for 17.19%(n=11) and 82.81%(n=53),respectively.Lymph node metastasis occurred in 24(37.50%) patients.The immunohistochemical staining results showed partially down-regulated or absent expression of SMARCA4 in 1(1.56%) patient,positive BRAF expression in 4(6.25%) patients,and mutant expression of P53 in 35(54.69%) patients.The PD-1-expressing tumor associated immune cell was proportion score<10% in 45(70.31%) patients and≥10% in 19(29.69%) patients.The PD-L1 combined positive score was<10 in 52(81.25%) patients and≥10 in 12(18.75%) patients.The gene fusion of NTRK1,NTRK2,and NTRK3 was negative in all the patients,and BRAF V600E gene mutation was positive in 4(6.25%) patients.The SMARCA4 gene alteration was not detected in the patient with partial expression missing of SMARCA4.The PD-L1 combine positive score was correlated with the deficient mismatch repair(dMMR)/microsatellite instability-high (MSI-H) and the PD-1 expression (χ2=10.223,P=0.001;χ2=11.979,P=0.001). Conclusions The down-regulated or absent SMARCA4 expression and NTRK gene fusion are rare in the patients with colorectal cancer in Tibet.A few patients present BRAF V600E gene mutations,and Pan-TRK and BRAF expression can be used for the primary screening of NTRK gene fusion and BRAF gene mutation.The patients with dMMR/MSI-H are prone to high expression of PD-L1 and expected to benefit from immunotherapy.No significant correlation exists between P53 mutation and PD-L1 expression.The high expression of PD-1 is positively correlated with the high expression of PD-L1.

Temporal trends and regional variability in BRAF and KRAS genetic testing in Denmark (2010-2022): Implications for precision medicine.

This study aims to evaluate the developments in the testing of Kirsten Rat Sarcoma viral oncogene homolog (KRAS) and v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations across different cancer types and regions in Denmark from 2010 to 2022. Using comprehensive data from the Danish health registries, we linked molecular test results from the Danish Pathology Registry with cancer diagnoses from the Danish National Patient Registry between 2010 and 2022. We assessed the frequency and distribution of KRAS and BRAF mutations across all cancer types, years of testing, and the five Danish regions. The study included records of KRAS testing for 30 671 patients and BRAF testing for 30 860 patients. Most KRAS testing was performed in colorectal (78%) and lung cancer (18%), and BRAF testing in malignant melanoma (13%), colorectal cancer (67%), and lung cancer (12%). Testing rates and documentation mutational subtypes increased over time. Reporting of wildtype results varied between lung and colorectal cancer, with underreporting in lung cancer. Regional variations in testing and reporting were observed. Our study highlights substantial progress in KRAS and BRAF testing in Denmark from 2010 to 2022, evidenced by increased and more specific reporting of mutational test results, thereby improving the precision of cancer diagnosis and treatment. However, persistent regional variations and limited testing for cancer types beyond melanoma, colorectal, and lung cancer highlight the necessity for a nationwide assessment of the optimal testing approach.

Antitumor activity of extracellular signal-regulated kinases 1/2 inhibitor BVD-523 (ulixertinib) on thyroid cancer cells.

This study aimed to investigate BVD-523 (ulixertinib), an adenosine triphosphate (ATP)-dependent extracellular signal-regulated kinases 1/2 inhibitor, for its antitumor potential in thyroid cancer. Ten thyroid cancer cell lines known to carry mitogen-activated protein kinase (MAPK)-activated mutations, including v-Raf murine sarcoma viral oncogene homolog B (BRAF) and rat sarcoma virus (RAS) mutations, were examined. Cells were exposed to a 10-fold concentration gradient ranging from 0 to 3000 nM for 5 days. The half-inhibitory concentration was determined using the Cell Counting Kit-8 assay. Following BVD-523 treatment, cell cycle analysis was conducted using flow cytometry. In addition, the impact of BVD-523 on extracellular signal-regulated kinase (ERK)- dependent ribosomal S6 kinase (RSK) activation and the expression of cell cycle markers were assessed through western blot analysis. BVD-523 significantly inhibited thyroid cancer cell proliferation and induced G1/S cell cycle arrest dose-dependently. Notably, cell lines carrying MAPK mutations, especially those with the BRAF V600E mutation, exhibited heightened sensitivity to BVD-523's antitumor effects. Furthermore, BVD-523 suppressed cyclin D1 and phosphorylated retinoblastoma protein expression, and it robustly increased p27 levels in an RSK-independent manner. This study reveals the potent antitumor activity of BVD-523 against thyroid cancer cells bearing MAPK-activating mutations, offering promise for treating aggressive forms of thyroid cancer.

BRAF V600E Mutation in Malignant Melanoma-A Romanian Research Experience.

Background and Objectives: The most common mutation in malignant melanoma (MM) is the single-point mutation of v-raf murine sarcoma viral oncogene homolog B1 (BRAF) oncogene. Our study aims to evaluate BRAF V600E mutation, highlighting its frequency differences in primary versus metastatic MM. Materials and Methods: The study group comprised 133 patients diagnosed with MM in several county hospitals of the north-eastern region of Romania who have been assigned for investigation into BRAF V600E mutation in the private medical system. The material consisted of archived formalin-fixed paraffin-embedded (FFPE) blocks. BRAF V600E mutation was identified using the fully automated IdyllaTM BRAF mutation test system. Results: Out of the total of 133 cases, 78 cases were primary tumors, while 55 cases were metastatic MMs. Genetic analysis revealed the presence of BRAF V600E mutation in 66 cases (49.62%) and the wild-type genotype in 67 cases (50.37%). We found a statistically significant difference of the mutation frequency according to age (p = 0.0072). The mutated genotype was found in 45 cases out of 78 primary MMs (57.69%) and in 21 cases out of 55 secondary MMs (38.18%), with a statistically significant difference in favor of primary tumors (p = 0.0413). The correlations between the histopathological types, Clark's level, Breslow index, ulceration, and lymphovascular invasion, respectively, and the mutated genotype were not statistically significant. BRAF V600E mutation was identified in 15 out of 40 secondary tumors with lymph node location (37.5%) and in 6 out of 15 secondary tumors with another location (40%) without statistically significant differences between the mutation frequency and the location of the secondary tumors. Conclusions: Our results support MM high genetic heterogeneity, pointing out the relationship between BRAF V600E mutation and several clinicopathological characteristics, in primary and metastatic MMs, stressing the importance of BRAF testing implementation in Romania.

Is there a prognostic difference among stage I lung adenocarcinoma patients with different BRAF-mutation status?

The data of the prognostic role of V-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations in early-stage lung adenocarcinoma (LUAD) patients is scarce. This study aimed to investigate the proportion, clinicopathological features, and prognostic significance of patients with stage I LUAD carrying BRAF mutations. We collected 431 patients with pathological stage I LUAD from cBioPortal for Cancer Genomics and 1604 LUAD patients tested for BRAF V600E and epidermal growth factor receptor (EGFR) mutations from Shanghai Pulmonary Hospital. Survival curves were drawn by the Kaplan-Meier method and compared by log-rank test. Cox proportional hazard models, propensity-score matching (PSM), and overlap weighting (OW) were performed in this study. The primary endpoint was recurrence-free survival (RFS). The proportion of BRAF mutations was estimated at 5.6% in a Caucasian cohort. BRAF V600E mutations were detected in six (1.4%) patients in Caucasian populations and 16 (1.0%) patients in Chinese populations. Two BRAF V600E-mutant patients were detected to have concurrent EGFR mutations, one for 19-del and one for L858R. For pathological stage I LUAD patients, BRAF mutations were not significantly associated with worse RFS than wild-type BRAF patients (HR = 1.111; p = 0.885). After PSM and OW, similar results were presented (HR = 1.352; p = 0.742 and HR = 1.246; p = 0.764, respectively). BRAF V600E mutation status also lacked predictive significance for RFS (HR, 1.844; p = 0.226; HR = 1.144; p = 0.831 and HR = 1.466; p = 0.450, respectively). In this study, we demonstrated that BRAF status may not be capable of predicting prognosis in stage I LUAD patients. There is a need for more data to validate our findings.

Association of MDM2 Overexpression in Ameloblastomas with MDM2 Amplification and BRAFV600E Expression.

Ameloblastoma is a rare tumor but represents the most common odontogenic neoplasm. It is localized in the jaws and, although it is a benign, slow-growing tumor, it has an aggressive local behavior and high recurrence rate. Therefore, alternative treatment options or complementary to surgery have been evaluated, with the most promising one among them being a targeted therapy with the v-Raf murine sarcoma viral oncogene homologue B (BRAF), as in ameloblastoma the activating mutation V600E in BRAF is common. Studies in other tumors have shown that the synchronous inhibition of BRAF and human murine double minute 2 homologue (MDM2 or HDM2) protein is more effective than BRAF monotherapy, particularly in the presence of wild type p53 (WTp53). To investigate the MDM2 protein expression and gene amplification in ameloblastoma, in association with BRAFV600E and p53 expression. Forty-four cases of ameloblastoma fixed in 10% buffered formalin and embedded in paraffin were examined for MDM2 overexpression and BRAFV600E and p53 expression by immunohistochemistry, and for MDM2 ploidy with fluorescence in situ hybridization. Sixteen of forty-four (36.36%) cases of ameloblastoma showed MDM2 overexpression. Seven of sixteen MDM2-positive ameloblastomas (43.75%) were BRAFV600E positive and fifteen of sixteen MDM2-positive ameloblastomas (93.75%) were p53 negative. All MDM2 overexpressing tumors did not show copy number alterations for MDM2. Overexpression of MDM2 in ameloblastomas is not associated with MDM2 amplification, but most probably with MAPK activation and WTp53 expression. Further verification of those findings could form the basis for the use of MDM2 expression as a marker of MAPK activation in ameloblastomas and the trial of dual BRAF/MDM2 inhibition in the management of MDM2-overexpressing/BRAFV600E-positive/WTp53 ameloblastomas.