BRAF V600E mutation mediates invasive and growth features in ameloblastoma.

OBJECTIVES: Ameloblastoma (AM), a locally aggressive tumor with extensive growth capacity, causes significant damage to the jaw and affects facial appearance. Although the high prevalence of BRAF V600E mutation in AM is known, its specific impacts on patients with AM remain unclear. Thus, the present study investigated the role of BRAF V600E mutation, thereby focusing on its impact on AM invasion and growth. MATERIALS AND METHODS: Immunohistochemical analysis was used to compare BRAF V600E, MMP2, MMP9, and Ki-67 expressions in AM (n = 49), normal oral mucosa (NOM) (n = 10), and odontogenic keratocyst (OKC) (n = 15) tissues. AM was further classified according to the presence or absence of BRAF V600E. The relationship between BRAF V600E and invasion as well as growth was evaluated. In addition, correlation analysis was performed using immunohistochemistry and confirmed via double-labeling immunofluorescence. Finally, comparative analyses using mass spectrometry, immunohistochemistry, and immunofluorescence were performed to explore and identify underlying mechanisms. RESULTS: AM exhibited a higher incidence of BRAF V600E mutation than NOM and OKC. BRAF V600E expression was positively correlated with the invasion-associated proteins MMP2 and MMP9 and the growth-related protein Ki-67. Proteomic data revealed that BRAF V600E primarily activates the MAPK signaling pathway in AM, particularly driving the phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2). CONCLUSIONS: In summary, the findings suggested that the BRAF V600E mutation enhances the invasion and growth abilities of AM via the MAPK/ERK signaling pathway. Thus, targeting BRAF V600E or the MAPK/ERK pathway may be a potential AM therapy.

[New aspects in thyroid cancer treatment : Highlights of the 2019 ASCO Annual Meeting]. / Neue Aspekte in der Behandlung von Schilddrüsenkarzinomen : Highlights vom ASCO-Kongress 2019.

The majority of patients with thyroid cancer have a remarkably good chance of cure in the context of surgical treatment, due to their mostly local tumor spread. However, a small proportion of patients with advanced and metastatic thyroid tumors usually require multimodality treatment. Abstracts from the 2019 American Society of Clinical Oncology (ASCO) Annual Meeting are summarized in this review, to provide insights into current aspects of thyroid carcinoma treatment. In addition to innovations in the treatment of radioiodine-refractory differentiated and medullary thyroid carcinoma, current approaches to anaplastic thyroid carcinoma are presented and critically interpreted.

Screening and identification of Caulis Sinomenii bioactive ingredients with dual-target NF-κB inhibition and ß2- AR agonizing activities.

Caulis Sinomenii (CS) is a valuable traditional medicine in China. Its extract can act as an anti-inflammatory agent and a vascular smooth muscle relaxant. However, the underlying mechanisms remain unknown. In this study, we developed a simple dual-target method based on ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry combined with a dual-target bioactive screening assay for anti-inflammatory and antispasmodic activities to characterize the chemical structure of various bioactive compounds of CS rapidly. Seven potential NF-κB inhibitors were identified, including laudanosoline-1-O-xylopyranose, 6-O-methyl-laudanosoline-1-O-glucopyranoside, menisperine, sinomenine, laurifoline, magnoflorine and norsinoacutin. Furthermore, IL-6 and IL-8 assays confirmed the anti-inflammatory effects of these potential NF-κB inhibitors, in which laudanosoline-1-O-d-xylopyranose and menisperine were revealed as novel NF-κB inhibitors. Among the seven identified alkaloids, three potential ß2 -adrenergic receptor agonists, including sinomenine, magnoflorine and laurifoline, were characterized using a luciferase reporter system to measure for the activity of ß2 -adrenergic receptor agonists. Finally, sinomenine, magnoflorine and laurifoline were identified not only as potential NF-κB inhibitors but also as potential ß2 -adrenegic receptor agonists, which is the first time this has been reported. Molecular dynamic simulation and docking results suggest that the three dual-bioactive constituents could not only inhibit Pseudomonas aeruginosa PAK strain-induced inflammatory responses via a negative regulation of the Braf protein that participates in MAPK signaling pathway but also activate the ß2 -adrenegic receptor. These results suggest that CS extract has dual signaling activities with potential clinical application as a novel drug for asthma.

[Classification of malignant lymphomas. Current situation]. / Klassifikation maligner Lymphome. Aktueller Stand.

BACKGROUND: The World Health Organization (WHO) is planning an update of the WHO classification of malignant lymphomas. OBJECTIVE: To present new findings concerning the diagnostics and subclassification of malignant lymphomas. MATERIAL AND METHODS: A selective literature search ( http://www.ncbi.nlm.nih.gov ) was carried out and combined with the practical experiences of the authors in clinicopathological diagnostics. RESULTS: In recent years an increasing number of early lesions of malignant lymphomas have been described but the potential malignancy of these lesions is at least for some entities still uncertain. Newly defined entities have been described within the group of T-cell lymphomas and prognostic subgroups have been identified in the heterogeneous group of diffuse large B-cell lymphomas. Detection of mutations facilitates the differential diagnostics of morphologically similar diseases and can be an important component of the diagnostics. CONCLUSION: Recent scientific insights are being included more and more into the diagnostics of lymphomas. The update of the WHO classification is a consequence of these developments.

Targeting BRAF pathway in low-grade serous ovarian cancer.

Mutations in genes encoding for proteins along the RAS-RAF-MEK-ERK pathway have been detected in a variety of tumor entities including ovarian carcinomas. In the recent years, several inhibitors of this pathway have been developed, whose antitumor potential is currently being assessed in different clinical trials. Low grade serous ovarian carcinoma, is a rare gynecological tumor which shows favorable overall survival, compared to the general ovarian cancer population, but worrying resistance to conventional chemotherapies. The clinical behavior of low grade serous ovarian carcinoma reflects the different gene profile compared to high-grade serous carcinoma: KRAS/BRAF mutations. BRAF inhibitors as single agents were approved for the treatment of BRAF mutated tumors. Nevertheless, many patients face progressive disease. The understanding of the mechanisms of resistance to BRAF inhibitors therapy and preclinical studies showing that BRAF and mitogen-activated protein kinase kinase (MEK) inhibitors combined therapy delays the onset of resistance compared to BRAF inhibitor single agent, led to the clinical investigation of combined therapy. The aim of this paper is to review the efficacy and safety of the combination of BRAF plus MEK inhibitors on ovarian carcinomas, in particularly focusing on low grade serous ovarian carcinoma.

Effect of Primary Tumor Location on Postmetastasectomy Survival in Patients with Colorectal Cancer Liver Metastasis.

BACKGROUND: The effects of primary tumor location on colorectal liver metastasis (CRLM) and post-hepatic-metastasectomy overall survival (OS) are controversial. This study evaluated the difference in post-hepatic-metastasectomy OS among right-sided colon, left-sided colon, and rectal cancer groups. METHODS: In total, 381 patients who underwent curative-intent CRLM resection were enrolled. Patients were grouped based on the primary tumor location (right-sided, left-sided, and rectum). The Kaplan-Meier analysis and log-rank test were performed for survival analysis. The univariate and multivariate analyses of clinical and pathological factors were performed using the Cox proportional hazards model. RESULTS: Significant OS difference was noted among the three groups (log-rank, p = 0.014). The multivariate analysis revealed a 32% lower death risk in left-sided colon cancer compared with right-sided colon cancer (hazard ratio [HR] 0.68, p = 0.042), whereas no OS difference was noted between the rectal cancer and right-sided colon cancer groups. The left- versus right-sided OS advantage was noted only in the KRAS wild-type subgroup (HR 0.46, p = 0.002), and a rectal versus right-sided OS disadvantage was noted in the KRAS mutant subgroup (HR 1.78, p = 0.03). CONCLUSIONS: The CRLM post-hepatic-metastasectomy OS was superior in left-sided colon cancer than in right-sided colon cancer and was similar in rectal and right-sided colon cancer. The OS difference in different primary tumor locations is dependent on KRAS mutation status, with a decreased left- versus right-sided death risk noted only in KRAS wild-type colon cancer and an increased rectal versus right-sided death risk noted only in KRAS mutant colon cancer.

Relationships among KRAS mutation status, expression of RAS pathway signaling molecules, and clinicopathological features and prognosis of patients with colorectal cancer.

BACKGROUND: The RAS/RAF/MEK/ERK and PI3K/AKT/mTOR signaling pathways all belong to mitogen-activated protein kinase (MAPK) signaling pathways, Mutations in any one of the upstream genes (such as the RAS gene or the BRAF gene) may be transmitted to the protein through transcription or translation, resulting in abnormal activation of the signaling pathway. This study investigated the relationship between the KRAS gene mutation and the clinicopathological features and prognosis of colorectal cancer (CRC), and the effect of KRAS mutations on its associated proteins in CRC, with an aim to clarify the cause of tumor progression and drug resistance caused by mutation of the KRAS gene. AIM: To investigate the KRAS gene and RAS pathway signaling molecules in CRC and to analyze their relationship with clinicopathological features and prognosis. METHODS: Colorectal cancer tissue specimens from 196 patients were analyzed for KRAS mutations using quantitative polymerase chain reaction and for KRAS, BRAF, MEK, and ERK protein expression levels using immunohistochemistry of tumor microarrays. To analyze differences of RAS pathway signaling molecule expression levels in different KRAS gene status, the relationships between these parameters and clinicopathological features, 4-year progression-free survival, and overall survival were analyzed by independent sample t test, Kaplan-Meier plots, and the log-rank test. Predictors of overall and disease-free survival were assessed using a Cox proportional hazards model. RESULTS: Of the 196 patients, 62 (32%) carried mutations in codon 12 (53/62) or codon 13 (9/62) in exon 2 of the KRAS gene. KRAS, BRAF, ERK, and MEK protein expression was detected in 71.4%, 78.8%, 64.3%, and 50.8% of CRC tissues, respectively. There were no significant differences between KRAS mutation status and KRAS, BRAF, MEK, or ERK protein levels. Positive expression of KRAS and ERK was associated with poor tumor differentiation, and KRAS expression was also associated with age < 56 years. MEK expression was significantly associated with distant metastasis (P < 0.05). The 4-year progression-free survival rate, but not overall survival rate, was significantly higher in patients with KRAS-negative tumors than in those with KRAS-positive tumors (P < 0.05), whereas BRAF, MEK, and ERK expression was unrelated to survival. Multivariate analysis showed that only the expression of KRAS protein was a risk factor for tumor recurrence (P < 0.05). No other clinicopathological factors correlated with KRAS, BRAF, MEK, or ERK expression. CONCLUSION: KRAS gene mutations do not affect downstream protein expression in CRC. KRAS protein is associated with poor tumor differentiation, older age, and a risk of tumor recurrence.

Squamous Cell Differentiation in Metastatic Papillary Thyroid Carcinoma: Metaplastic Reversion or Progression?

Squamous cell differentiation (SCD) may occur in papillary thyroid carcinoma (PTC) only at metastatic sites. We have studied cytokeratin CK5/6 and P63 along with TTF1 (thyroid transcription factor 1) and B-Raf (V-Raf murine sarcoma viral oncogene homolog B1) immunohistochemical expression in neck lymph node metastases of thyroid PTC showing SCD. The patient (21-years) presented with a neck mass. The check-up revealed bilateral thyroid nodules. Total thyroidectomy and neck lymph node dissection were performed. The diagnosis was that of bilateral PTC with lymph node metastases (pT-1N1Mx). The metastases were peculiar by the presence of cystic change and of SCD. The thyroid PTC expressed P63 focally and, TTF1 and B-Raf diffusely. Cytokeratin 5/6 was expressed only in the lymph node metastases, in the metastatic cyst lining and in the SCD foci. The P63+ cells outnumbered those CK5/6+. TTF1 expression was faint in SCD. Metastatic, both classical PTCand SCD-epithelia expressed B-Raf. The expression patterns of CK5/6, P63, TTF1 suggest a luminal/central-to-abluminal/peripheral direction for SCD development from PTC-epithelia in lymph node metastases. Whether this metaplasia type may reflect a regression to a less aggressive morphotype or a progression-switch to squamous cell carcinoma-type differentiation in a composite tumor remains matter of debate.

Adjusting for treatment switching in the METRIC study shows further improved overall survival with trametinib compared with chemotherapy.

Trametinib, a selective inhibitor of mitogen-activated protein kinase kinase 1 (MEK1) and MEK2, significantly improves progression-free survival compared with chemotherapy in patients with BRAF V600E/K mutation-positive advanced or metastatic melanoma (MM). However, the pivotal clinical trial permitted randomized chemotherapy control group patients to switch to trametinib after disease progression, which confounded estimates of the overall survival (OS) advantage of trametinib. Our purpose was to estimate the switching-adjusted treatment effect of trametinib for OS and assess the suitability of each adjustment method in the primary efficacy population. Of the patients randomized to chemotherapy, 67.4% switched to trametinib. We applied the rank-preserving structural failure time model, inverse probability of censoring weights, and a two-stage accelerated failure time model to obtain estimates of the relative treatment effect adjusted for switching. The intent-to-treat (ITT) analysis estimated a 28% reduction in the hazard of death with trametinib treatment (hazard ratio [HR], 0.72; 95% CI, 0.52-0.98) for patients in the primary efficacy population (data cut May 20, 2013). Adjustment analyses deemed plausible provided OS HR point estimates ranging from 0.48 to 0.53. Similar reductions in the HR were estimated for the first-line metastatic subgroup. Treatment with trametinib, compared with chemotherapy, significantly reduced the risk of death and risk of disease progression in patients with BRAF V600E/K mutation-positive advanced melanoma or MM. Adjusting for switching resulted in lower HRs than those obtained from standard ITT analyses. However, CI are wide and results are sensitive to the assumptions associated with each adjustment method.

Use of BRAF v600e immunocytochemistry on FNA direct smears of papillary thyroid carcinoma.

BACKGROUND: Mutations of v-Raf murine sarcoma viral oncogene homolog B1 (BRAF) are identified in almost half of all papillary thyroid carcinomas (PTCs). These mutations are specific for PTC and may confer a worse prognosis. An immunohistochemical (IHC) stain for BRAF is commercially available and has been validated in surgical specimens. Fine-needle aspiration (FNA) is frequently used as a diagnostic tool for risk stratification of thyroid nodules. Therefore, the authors evaluated the performance of immunostaining with the anti-BRAF antibody VE1 on FNA direct smears. METHODS: The authors identified 51 FNA specimens that had subsequent surgical resection specimens with a diagnosis of PTC. BRAF VE1 IHC was performed on the surgical specimens to determine their mutation status. The corresponding direct smears were then stained using the same VE1 stain to assess correlation. RESULTS: Twenty-two of the 46 included surgical specimens were positive for BRAF mutations (47.8%) by IHC, consistent with the published rates. The paired cytologic smears from these cases revealed 65.3% concordance. The overall sensitivity of BRAF staining on cytologic smears was 63.6%, and the specificity was 58.3%. Concordance rates were highest in specimens that were diagnosed as malignant or suspicious for malignancy (75% and 85.7%, respectively). The negative predictive value increased to 77.8% when suspicious for follicular neoplasm/suspicious cases were combined. CONCLUSIONS: Specimens that were malignant or suspicious on FNA were most likely to be BRAF concordant. Limitations to the interpretation of smears included low cellularity and obscuring blood, macrophages, or colloid. With further refinement, it is possible that BRAF immunocytochemistry can be applied prospectively to thyroid FNAs for risk stratification and to reduce false-negative rates.

Predictive and prognostic roles of BRAF mutation in patients with metastatic colorectal cancer treated with anti-epidermal growth factor receptor monoclonal antibodies: a meta-analysis.

OBJECTIVE: This study aimed to evaluate the predictive and prognostic roles of BRAF mutation in patients with metastatic colorectal cancer (mCRC) treated with anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (MoAbs). METHODS: Computer searches of the literature on BRAF mutation in mCRC patients were performed. Studies with objective response rate (ORR) to anti-EGFR MoAbs and/or overall survival (OS) and progression-free survival (PFS) with different BRAF gene expression in mCRC patients were eligible. RESULTS: A total of 19 studies including 2875 patients was enrolled in the meta-analysis. BRAF mutation was detected in 246 patients. The ORR was 18.4% (40/217) in mutant BRAF group and 41.7% (831/1993) in the wild-type BRAF group. The overall risk ratio (RR) for the ORR of BRAF mutation patients compared with wild-type BRAF patients was 0.58 (95% confidence intervals [CI] 0.35-0.94, P = 0.027). The median PFS of patients with BRAF mutation was significantly shorter than that of patients with wild-type BRAF (hazard ratio [HR] 2.98, 95% CI 2.07-4.27, P < 0.001) and the median OS of patients with BRAF mutation was also significantly shorter than that of those with wild-type BRAF (HR 2.85, 95% CI 2.31-3.52, P < 0.001). CONCLUSION: BRAF mutation is associated with poor response to anti-EGFR MoAbs and it is an adverse prognostic biomarker of the survival of patients with mCRC.

Expression of BRAF protein in patients with papillary thyroid carcinoma and clinical significance of the research / 中国现代普通外科进展

Objective:To explore the Papillary thyroid carcinoma(PTC) in patients with the expression of BRAF protein and correlation with clinical indicators.Methods:During the selection from June 2015 to June 2016 in our hospital diagnosis and treatment of 120 patients with PTC as the observation group,the other choice during the same period in our hospital make a diagnosis and give treatment of PCT 57 cases as control group,patients with thyroid cancer by immunohistochemical method to detect mutated BRAF protein expression in two groups of patients,and analyze the BRAF protein positive expression and the correlation of PTC clinical indicators.Results:Observation group of patients BRAF protein positive rate was 74.17％,the negative rate was 25.83％,control group patients BRAF protein positive rate was 7.02％,the negative rate was 92.98％,the comparison between groups have significant statistical difference(P＜0.01);Age≤45 years,diameter of tumor＞1 cm,TNM staging for Ⅲ ～Ⅳ stage of PTC patients of BRAF protein positive rate were 96.43％,82.35％,95.65％,significantly higher than the age＞45 years,tumor diameter＜1cm,TNM staging for Ⅰ ～ Ⅱ stage were 67.39％,63.46％,69.07％,and the corresponding comparison have significant statistical difference(P＜0.05).Conclusion:PTC mutated BRAF protein positive rate was significantly higher in patients with non PTC thyroid cancer patients,patients with PTC BRAF protein positive expression related to age,tumor diameter and tumor stage.

Análisis molecular del cáncer de colon esporádico / Molecular analysis of sporadic colon cancer

Background: In Chile, colorectal cancer (CRC) is often diagnosed in late stages. Thus, surgical treatment must be complemented with chemotherapy. KRAS mutations and microsatellite instability have been detected in these tumors. However, the response to treatment in patients without KRAS mutations varies and requires a better understanding. Aim: To determine the frequency and distribution of somatic point mutations in KRAS, BRAF and PIK3CA genes and microsatellite instability status (MSI) in patients with colon cancer (CC). Material and Methods: A prospective observational study of patients undergoing surgery for colon cancer. Tumor-derived DNA was analyzed by polymerase chain reaction (PCR) for the most frequent mutations of KRAS, BRAF and PIK3CA. PCR was also used to analyze MSI. Results: Fifty-eight patients with sporadic CC were analyzed, 16 showed KRAS mutations (G12R, G12D, G12V, G13D) and out of the 42 patients that did not show any mutation, 10 had mutations in BRAF (V600E) and PIK3CA (E542K, E545D, E545K, Q546E, H1047R). BRAF mutations alone or in combination with PIK3CA mutations were observed in 27% of high MSI tumors and in 2% of tumors without instability (p < 0.049). A higher percentage of high MSI tumors were located in the right colon (p < 0.001), and showed BRAF mutation (p < 0.020). Conclusions: The highest percentage of high MSI and BRAF mutations was observed in the right colon. Therefore, this study suggests the presence of different molecular features between right and left colon tumors that should be considered when defining the therapeutic management.

Mutations of the BRAF Gene in Papillary Thyroid Carcinoma in a Korean Population

The B-type Raf kinase (BRAF) protein is a serine/threonine kinase that has an important role in cellular proliferation, differentiation, and programmed cell death. The BRAF gene has been recently found to be mutated in human carcinomas, predominantly in malignant melanoma. The aim of this study was to investigate the frequency of the BRAF mutation in papillary thyroid carcinoma (PTC) of Koreans through direct DNA sequencing of the polymerase chain reaction (PCR) - amplified exon 15 with clinicopathological features. Seventy paraffin-embedded conventional papillary carcinomas in the thyroid gland were evaluated. The BRAF missense mutation at V599E was found in 58 of 70 PTCs (83%). The frequency of our series was much higher than the frequencies of other PTC series (36 - 69%). The frequency of nodal metastasis was also significantly higher in the BRAF mutation group (p= 0.048). These results suggest that the BRAF mutation is involved in the carcinogenesis in most conventional PTCs, especially those occurring in Koreans, and this is a potentially valuable marker for the evaluation of prognosis of patients with PTC. These findings support the specific inhibitors of BRAF being promising targets for the disease outcome.