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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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 PTC- and 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. [ABSTRACT FROM AUTHOR]

Abstract: Over the last few years, BRAF has emerged as a validated target in melanoma. This review summarises recent advances in the development of BRAF inhibitors, focussing on agents that have been assessed clinically. [Copyright &y& Elsevier]

Diagnosis of Borderline papillary serous tumor of the fallopian tube was comprehensively established by Zheng in 1996 supported mostly by a histological similarity to its ovarian counterpart. It is a very rare entity with eight cases published so far and the ninth case described here as a 41-year-old woman presented with non-specific lower abdominal pain, dyspareunia and dysuria. Left adnexal mass was identified and she was operated on. It turned out the tumor was attached exclusively to the left tube, with no connection to any of the surrounding structures and with histology of borderline serous tumor with non-invasive implants in the left and right ovary and visceral peritoneum. Reviewing available data on genetics of these tumors there was diploid status in one examined tumor, and in our case no mutations of KRAS, BRAF and p53 genes were found. Histomorphology remains the mainstay of diagnosis and staging operation is the mainstay of patient management. Prognosis is uncertain with a 6-year survival documented in one case. [ABSTRACT FROM AUTHOR]

The article presents a case study of a 10-year-old boy who was referred for dysmorphological evaluation due to severe developmental delay, short stature and dysmorphic features. He was diagnosed with cardiofaciocutaneous syndrome (CFC) on the basis of the observed facial dysmorphisms, hypertrophic cardiomyopathy and mental retardation. The authors notes that CFC is caused by mutations in BRAF, MEK1, MEK2, KRAS genes encoding proteins of the RAS/MAPK signaling pathway.