Recent advances in molecular diagnostics have led to significant insights into the genetic basis of thyroid tumorigenesis. Among the mutations commonly seen in thyroid cancers, the vast majority are associated with the mitogen-activated protein kinase pathway. B-Raf proto-oncogene (BRAF) mutations are the most common mutations observed in papillary thyroid cancers (PTCs), followed by RET/PTC rearrangements and RAS mutations, while follicular thyroid cancers are more likely to harbor RAS mutations or PAX8/peroxisome proliferator-activated receptor gamma (PPARgamma) rearrangements. Beyond these more common mutations, alterations in the telomerase reverse transcriptase (TERT) promoter have recently been associated with clinicopathologic features, disease prognosis, and tumorigenesis in thyroid cancer. While the mutations underlying thyroid tumorigenesis are well known, the frequency of these mutations is strongly associated with geography, with clear differences reported between Asian and Western countries. Of particular interest is the prevalence of BRAF mutations, with Korean patients exhibiting the highest rate of BRAF-associated thyroid cancers in the world. Here, we review the prevalence of each of the most common mutations in Asian and Western countries, and identify the characteristics of well-differentiated thyroid cancer in Asians.
Asia ; Asian Continental Ancestry Group* ; Carcinogenesis ; Geography ; Humans ; Pathology, Molecular ; PPAR gamma ; Prevalence ; Prognosis ; Protein Kinases ; Proto-Oncogene Proteins B-raf ; Proto-Oncogenes ; Telomerase ; Thyroid Gland* ; Thyroid Neoplasms*

<b>INTRODUCTIONb>An increasing number of targeted drugs have been tested for the treatment of nasopharyngeal carcinoma (NPC). However, targeted therapy-related oncogenic mutations have not been fully evaluated. This study aimed to detect targeted therapy-related oncogenic mutations in NPC and to determine which targeted therapy might be potentially effective in treating NPC.

<b>METHODSb>By using the SNaPshot assay, a rapid detection method, 19 mutation hotspots in 6 targeted therapy-related oncogenes were examined in 70 NPC patients. The associations between oncogenic mutations and clinicopathologic factors were analyzed.

<b>RESULTSb>Among 70 patients, 12 (17.1%) had mutations in 5 oncogenes: 7 (10.0%) had v-kit Hardy-Zuckerman 4 feline sarcoma viral oncogene homolog (KIT) mutation, 2 (2.8%) had epidermal growth factor receptor (EGFR) mutation, 1 (1.4%) had phosphatidylinositol-4,5-bisphosphate 3-kinase, catalytic subunit alpha (PIK3CA) mutation, 1 (1.4%) had Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation, and 1 (1.4%) had simultaneous EGFR and v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) mutations. No significant differences were observed between oncogenic mutations and clinicopathologic characteristics. Additionally, these oncogenic mutations were not associated with tumor recurrence and metastasis.

<b>CONCLUSIONSb>Oncogenic mutations are present in NPC patients. The efficacy of targeted drugs on patients with the related oncogenic mutations requires further validation.

Carcinoma ; Class I Phosphatidylinositol 3-Kinases ; Humans ; Mutation ; Nasopharyngeal Neoplasms ; Neoplasm Recurrence, Local ; Oncogenes ; Pharmacogenetics ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins B-raf ; Receptor, Epidermal Growth Factor

Odontogenic tumors are rare lesions with unknown etiopathogenesis. Most of them are benign, but local aggressiveness, infiltrative potential, and high recurrence rate characterize some entities. The MAP-kinase pathway activation can represent a primary critical event in odontogenic tumorigenesis. Especially, the BRAF V600E mutation has been involved in 80-90% of ameloblastic lesions, offering a biological rationale for developing new targeted therapies. The study aims to evaluate the BRAF V600E mutation in odontogenic lesions, comparing three different detection methods and focusing on the Sequenom MassARRAY System. 81 surgical samples of odontogenic lesions were subjected to immunohistochemical analysis, Sanger Sequencing, and Matrix-Assisted Laser Desorption/Ionization-Time of Flight mass spectrometry (Sequenom). The BRAF V600E mutation was revealed only in ameloblastoma samples. Moreover, the presence of BRAF V600E was significantly associated with the mandibular site (ρ = 0.627; P value <0.001) and the unicystic histotype (ρ = 0.299, P value <0.001). However, any significant difference of 10-years disease-free survival time was not revealed. Finally, Sequenom showed to be a 100% sensitive and 98.1% specific, suggesting its high-performance diagnostic accuracy. These results suggest the MAP-kinase pathway could contribute to ameloblastic tumorigenesis. Moreover, they could indicate the anatomical specificity of the driving mutations of mandibular ameloblastomas, providing a biological rational for developing new targeted therapies. Finally, the high diagnostic accuracy of Sequenom was confirmed.
Ameloblastoma/pathology* ; Carcinogenesis ; Humans ; Mitogen-Activated Protein Kinases/genetics* ; Mutation ; Odontogenic Tumors/pathology* ; Proto-Oncogene Proteins B-raf/metabolism* ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization

<b>OBJECTIVEb>To study the effect of Mps1 on BRAFWT/MEK/ERK pathway in the presence of wild type BRAF or BRAFV600E in melanoma.

<b>METHODSb>Melanoma cells harboring BRAFWT genotype were transfected either with pBabe-puro-GST-BRAF-WT and/or pBabe-puro-GFP-Mps1-WT or pBabe-puro-GST-BRAFV600E and/or pBabe-puro-GFP-Mps1-WT, followed by Western blot to detect Mps1 and p-ERK expression. The melanoma cells harboring BRAFWT and BRAFV600E genotype were infected with pSUPER-Mps1 retrovirus to knockdown the endogenous Mps1 protein, followed by Western blot to detect Mps1 and p-ERK expression. Meanwhile, melanoma cells harboring BRAFV600E genotype were infected with pBabe-puro-GFP-Mps1 and Western blot was performed to detect Mps1 and p-ERK expression.

<b>RESULTSb>In melanoma cells harboring BRAFWT genotype and transfected with pBabe-puro-GST-BRAF-WT and pBabe-puro-GFP-Mps1-WT, phospho-ERK levels were notably reduced as compared to either negative control or empty vector. However, cells transfected with pBabe-puro-GST-BRAFV600E and pBabe-puro-GFP-Mps1-WT, phospho-ERK levels did not change significantly compared with either negative control or empty vector. Knockout of Mps1 in BRAF wild-type cell lines led to an increased ERK activity. However, there was no significant change of ERK activity in BRAFV600E cell lines in the absence of Mps1. The expression of p-ERK in BRAFV600E mutant cell lines infected with pBabe-puro-GFP-Mps1-WT did not show any significant difference from either negative control or empty vector.

<b>CONCLUSIONSb>Based on these findings, it suggests that there exists an auto-regulatory negative feedback loop between the Mps1 kinase and BRAFWT/ERK signaling. Oncogenic BRAFV600E abrogates the regulatory negative feedback loop of Mps1 on the MAPK pathway.

Cell Cycle Proteins ; metabolism ; Cell Line, Tumor ; Humans ; MAP Kinase Signaling System ; Melanoma ; genetics ; metabolism ; Mutation ; Phenotype ; Protein-Serine-Threonine Kinases ; metabolism ; Protein-Tyrosine Kinases ; metabolism ; Proto-Oncogene Proteins B-raf ; metabolism ; Signal Transduction ; Transfection

<b>OBJECTIVEb>To investigate PIK3CA, PTEN status in the primary lesion of colorectal cancer (CRC): relationship with occurrences of liver metastasis and its prognosis.

<b>METHODSb>Patients with CRC who had the primary tumor resected between 2003 and 2008 were selected and enrolled into three groups according to the occurrence of liver metastasis. The mutations of PIK3CA exon 9 and 20, PTEN exon 5, 7, 8 in primary cancer cells in formalin-fixed, paraffin-embedded specimens were detected by Pyrosequencing, then a statistical analysis was deduced to find out the relationship between PIK3CA, PTEN status and occurrences of liver metastasis as well as the prognosis.

<b>RESULTSb>Of all the 300 CRC cases, the mutation rates of PIK3CA and PTEN was 18.2% (51/300) and 16.3% (49/300). The multivariate Logistic analysis revealed that exon 5 mutation of PTEN was one of the independent risk factors of occurrence of metachronous liver metastasis in CRC patients (HR = 1.634, 95%CI: 1.796 - 3.355, P = 0.041). Patients with PTEN mutation had a poorer overall survival in group with synchronous liver metastasis (median survival time 62.0 months vs 71.0 months, χ(2) = 12.942, P = 0.048) while CRC patients who had the liver metastasis resected in group of synchronous and metachronous liver metastasis had a poorer disease free survival rates with PIK3CA mutation (median survival time 16.0 months vs 25.0 months, χ(2) = 9.679, P = 0.037).

<b>CONCLUSIONSb>The exon 5 mutation of PTEN of CRC is potentially correlated with the occurrence of synchronous liver metastasis. CRC patients who had the liver metatasis resected but with PIK3CA mutation could have a poorer prognosis.

Aged ; Class I Phosphatidylinositol 3-Kinases ; Colorectal Neoplasms ; genetics ; pathology ; Female ; Humans ; Liver Neoplasms ; genetics ; secondary ; Male ; Middle Aged ; Mutation ; PTEN Phosphohydrolase ; genetics ; Phosphatidylinositol 3-Kinases ; genetics ; Prognosis ; Proto-Oncogene Proteins B-raf ; genetics ; Survival Analysis

As molecular targets continue to be identified and more targeted inhibitors are developed for personalized treatment of non-small cell lung cancer (NSCLC), multigene mutation determination will be needed for routine oncology practice and for clinical trials. In this study, we evaluated the sensitivity and specificity of multigene mutation testing by using the Snapshot assay in NSCLC. We retrospectively reviewed a cohort of 110 consecutive NSCLC specimens for which epidermal growth factor receptor (EGFR) mutation testing was performed between November 2011 and December 2011 using Sanger sequencing. Using the Snapshot assay, mutation statuses were detected for EGFR, Kirsten rate sarcoma viral oncogene homolog (KRAS), phosphoinositide-3-kinase catalytic alpha polypeptide (PIK3CA), v-Raf murine sarcoma viral oncogene homolog B1 (BRAF), v-ras neuroblastoma viral oncogene homolog (NRAS), dual specificity mitogen activated protein kinase kinase 1 (MEK1), phosphatase and tensin homolog (PTEN), and human epidermal growth factor receptor 2 (HER2) in patient specimens and cell line DNA. Snapshot data were compared to Sanger sequencing data. Of the 110 samples, 51 (46.4%) harbored at least one mutation. The mutation frequency in adenocarcinoma specimens was 55.6%, and the frequencies of EGFR, KRAS, PIK3CA, PTEN, and MEK1 mutations were 35.5%, 9.1%, 3.6%, 0.9%, and 0.9%, respectively. No mutation was found in the HER2, NRAS, or BRAF genes. Three of the 51 mutant samples harbored double mutations: two PIK3CA mutations coexisted with KRAS or EGFR mutations, and another KRAS mutation coexisted with a PTEN mutation. Among the 110 samples, 47 were surgical specimens, 60 were biopsy specimens, and 3 were cytological specimens; the corresponding mutation frequencies were 51.1%, 41.7%, and 66.7%, respectively (P = 0.532). Compared to Sanger sequencing, Snapshot specificity was 98.4% and sensitivity was 100% (positive predictive value, 97.9%; negative predictive value, 100%). The Snapshot assay is a sensitive and easily customized assay for multigene mutation testing in clinical practice.
Adenocarcinoma ; genetics ; Carcinoma, Non-Small-Cell Lung ; genetics ; Class I Phosphatidylinositol 3-Kinases ; Genes, erbB-1 ; Genes, erbB-2 ; Genes, ras ; Humans ; Mutation ; PTEN Phosphohydrolase ; Phosphatidylinositol 3-Kinases ; Proto-Oncogene Proteins ; Proto-Oncogene Proteins B-raf ; Proto-Oncogene Proteins p21(ras) ; Retrospective Studies ; ras Proteins

<b>OBJECTIVEb>To investigate the mutation frequencies of KRAS, BRAF, PIK3CA and EGFR genes that were effective on the targeted therapies in colorectal carcinoma.

<b>METHODSb>The tissue specimens from 331 colorectal cancer patients were collected and subject to KRAS, BRAF, PIK3CA and EGFR mutation analysis. Paraffin-embedded tissue samples were obtained and macrodissection was performed to enrich the tumor cells for DNA extraction when necessary. PCR-based direct DNA sequencing was used to investigate the codons 12 and 13 in exon 2 of KRAS gene, exons 11 and 15 of BRAF gene, exons 9 and 20 of PIK3CA gene and exons 18-21 of EGFR gene.

<b>RESULTSb>Activating mutations were detected in KRAS (44.1%, 137/311), BRAF (5.8%, 9/156), PIK3CA (2.6%, 4/156) and EGFR (1.3%, 2/156) in the study cohort of colorectal carcinoma cases. Among KRAS gene mutations, 81.0% (111/137) occurred in codon 12, with p.G12D as the most common variant (45.3%, 62/137); 19.0% (26/137) occurred in codon 13, with 38G > A (G13D) as the most common variant (17.5%, 24/137).

<b>CONCLUSIONSb>The KRAS mutation frequency is the highest among the four genes (KRAS, BRAF, PIK3CA and EGFT) tested in colorectal carcinoma. The presence of these gene mutations may provide therapeutic information for targeted therapy. Mutation analyses of BRAF and PIK3CA in addition to KRAS should be a part of the standard diagnostic algorithm for colorectal carcinoma patients.

Class I Phosphatidylinositol 3-Kinases ; Codon ; Colorectal Neoplasms ; genetics ; pathology ; DNA Mutational Analysis ; Exons ; Female ; Humans ; Male ; Middle Aged ; Mutation ; Phosphatidylinositol 3-Kinases ; genetics ; Proto-Oncogene Proteins ; genetics ; Proto-Oncogene Proteins B-raf ; genetics ; Proto-Oncogene Proteins p21(ras) ; Receptor, Epidermal Growth Factor ; genetics ; ras Proteins ; genetics

Neuronal atrophy is a common pathological feature occurred in aging and neurodegenerative diseases. A variety of abnormalities including motor protein malfunction and mitochondrial dysfunction contribute to the loss of neuronal architecture; however, less is known about the intracellular signaling pathways that can protect against or delay this pathogenic process. Here, we show that the DYNC1I1 deficiency, a neuron-specific dynein intermediate chain, causes neuronal atrophy in primary hippocampal neurons. With this cellular model, we are able to find that activation of RAS-RAF-MEK signaling protects against neuronal atrophy induced by DYNC1I1 deficiency, which relies on MEK-dependent autophagy in neuron. Moreover, we further reveal that BRAF also protects against neuronal atrophy induced by mitochondrial impairment. These findings demonstrate protective roles of the RAS-RAF-MEK axis against neuronal atrophy, and imply a new therapeutic target for clinical intervention.
Animals ; Cell Line ; Cytoplasmic Dyneins ; genetics ; metabolism ; Hippocampus ; metabolism ; pathology ; MAP Kinase Kinase Kinases ; genetics ; metabolism ; MAP Kinase Signaling System ; Mice ; Mice, Knockout ; Neurodegenerative Diseases ; genetics ; metabolism ; pathology ; Proto-Oncogene Proteins B-raf ; genetics ; metabolism ; ras Proteins ; genetics ; metabolism

Objective:b> To investigate the frequency of neurotrophic tyrosine receptor kinase (NTRK) gene variations in papillary thyroid carcinoma (PTC) and to analyze the feasibility of detecting tropomyosin receptor kinase (TRK) proteins using immunohistochemistry (IHC) to predict the fusion variation of NTRK. Methods:b> A cohort of 848 PTC cases was collected at the Department of Pathology, Shenzhen People's Hospital from June 2017 to June 2020. The expression levels of TRK proteins were detected using IHC in 848 PTC samples, and the DNA-based next generation sequencing (NGS) was performed to detect NTRK rearrangements in 150 PTCs. Results:b> There were 242 males and 606 females, with an age range of 9-83 years. In 120 cases with TRK expression detected by IHC, 13 cases were confirmed to harbor a NTRK gene fusion by NGS. The frequency of NTRK fusion in PTC was 1.5% (13/848). The sensitivity and specificity of TRK-IHC positivity for screening NTRK fusion in PTC were 100% and 21.9%, respectively. The specificity of weak-, moderate- and strong-positive stains of TRK IHC were 23.8%, 76.9% and 93.8%, respectively. The specificity of NTRK gene fusion was predicted to increase with the enhanced intensity of IHC staining. In BRAF V600E negative PTC samples, the specificity of weak-and moderate-positive stains of TRK IHC increased to 62.5% and 96.8%, respectively. Seven NTRK fusion partners were found in the PTC, including EML4, ETV6, CDH1, GJD2, TPR, TFG and SQSTM1. Conclusions:b> There is a low variation frequency of NTRK gene fusion in PTC. TRK IHC can be used as a screening method for NTRK fusion variation in PTC. The specificity of TRK IHC predicting NTRK fusion can be further enhanced by increasing the cutoff value of the positive cell number and staining intensity of TRK-IHC staining, or being combined with BRAF V600E negativity.
Adolescent ; Adult ; Aged ; Aged, 80 and over ; Child ; Female ; Gene Fusion ; Humans ; Immunohistochemistry ; Male ; Middle Aged ; Proto-Oncogene Proteins B-raf/genetics* ; Receptor Protein-Tyrosine Kinases/genetics* ; Receptor, trkA/genetics* ; Thyroid Cancer, Papillary/genetics* ; Thyroid Neoplasms/pathology* ; Young Adult

V-Raf murine sarcoma viral oncogene homolog B (BRAF) alteration is one of the most essential driver genes of non-small cell lung cancer (NSCLC). BRAF encodes serine/threonine protein kinases, and its mutations typically lead to protein compositional activation, thereby activating the mitogen-activated protein kinase kinase (MEK) signaling pathway. A promising new approach for the treatment of mutated BRAF and/or downstream MEK may provide customized treatment opportunities for BRAF driven NSCLC patients. However, combination therapy is necessary to overcome the difficulties such as short duration of benefit, poor therapeutic effect of non-V600 BRAF mutations and susceptibility to drug resistance. This article reviewed the progress in structural characteristics, related signaling pathways, mutation types of BRAF gene, and the clinical pathological relationship between BRAF mutations and NSCLC, as well as the therapy, in order to provide more evidences for clinical doctors to make treatment decisions.
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Animals ; Mice ; Humans ; Carcinoma, Non-Small-Cell Lung/pathology* ; Lung Neoplasms/pathology* ; Proto-Oncogene Proteins B-raf/genetics* ; Mutation ; Mitogen-Activated Protein Kinase Kinases/therapeutic use* ; Protein Kinase Inhibitors/therapeutic use*