Oncogenic mutations of BRAF occur in approximately 10% of colon cancers and are associated with their resistance to clinically available therapeutic drugs and poor prognosis of the patients. Here we report that colon cancer cells with mutant BRAF are also resistant to the heat shock protein 90 (HSP90) inhibitor AUY922, and that this is caused by rebound activation of ERK and Akt. Although AUY92...

BRAF is a major oncogenic mutation found in approximately 50% of human melanoma that confers constitutive activation of the MAPK pathway and increased melanoma growth. Inhibition of BRAF by oncogene targeting therapy increases overall survival of patients with melanoma, but is unable to produce many durable responses. Adaptive drug resistance remains the main limitation to BRAF inhibitor clinic...

Advanced human thyroid cancers, particularly those that are refractory to treatment with radioiodine (RAI), have a high prevalence of BRAF (v-raf murine sarcoma viral oncogene homolog B1) mutations. However, the degree to which these cancers are dependent on BRAF expression is still unclear. To address this question, we generated mice expressing one of the most commonly detected BRAF mutations ...

The activating mutation BRAF is the most prevalent genetic alteration in papillary thyroid carcinomas (PTC). It is associated with advanced PTCs, suggesting that this oncoprotein confers thyroid cancers with more aggressive properties. BRAF is also observed in thyroid micropapillary carcinomas and may thus be an early event in tumor development. To explore its biological consequences, we establ...

PURPOSE To gain a better understanding of the molecular events leading to the development of conjunctival melanocytic lesions and conjunctival melanoma, this study was conducted to investigate the presence of T1799A BRAF oncogenic mutation in these lesions. METHODS Forty-eight surgically excised conjunctival melanocytic lesions from 48 patients were examined for the presence of the BRAF T1799...

Previously, the authors have identified that c-Met mediates reactivation of the PI3K/AKT pathway following BRAF inhibitor treatment in BRAF (V600E) mutant anaplastic thyroid cancer, thereby contributing to the acquired drug resistance. Therefore dual inhibition of BRAF and c-Met led to sustained treatment response, thereby maximizing the specific anti-tumor effect of targeted therapy. The prese...

A critical step toward defining tailored therapy in patients with cancer is the identification of genetic interactions that may impair-or boost-the efficacy of selected therapeutic approaches. Cell models able to recapitulate combinations of genetic aberrations are important to find drug-genotype interactions poorly affected by the heterogeneous genetics of human tumors. In order to identify no...

We recently identified the secreted protein IGFBP7 as a factor required for an activated BRAF oncogene to induce senescence or apoptosis in primary human cells. In human melanomas containing an activating BRAF mutation (BRAF-positive melanomas), IGFBP7 is epigenetically silenced, which seems to be a critical step in melanoma genesis. Restoration of IGFBP7 function by the addition of recombinant...

BRAF-targeted therapy results in objective responses in the majority of patients; however, the responses are short lived (∼6 months). In contrast, treatment with immune checkpoint inhibitors results in a lower response rate, but the responses tend to be more durable. BRAF inhibition results in a more favorable tumor microenvironment in patients, with an increase in CD8(+) T-cell infiltrate and ...

BACKGROUND Thyroid cancer is a rare disease characterized by the subtle appearance of a nodule. Fine-needle cytology (FNC) is the first diagnostic procedure used to distinguish a benign from a malignant nodule. However, FNC yields inconclusive results in about 20% of cases. BRAF(V600E) mutation is the most frequent genetic alteration in papillary thyroid carcinoma (PTC); its high prevalence mak...