Melanoma cell expression of the nerve growth factor receptor CD271 is associated with stem-like properties. However, the contributing role of the receptor in melanoma cell migration is elusive. Here, we explored extracranial (skin, soft tissue, lymph node and liver, n = 13) and matched brain metastases (BM, n = 12) and observed a heterogeneous distribution of phenotypically distinct subsets of CD271+ cells. In addition, we observed that CD271 expression gradually rises along with melanoma progression and metastasis by exploration of publicly available expression data of nevi, primary melanoma (n = 31) and melanoma metastases (n = 54). Furthermore, we observed highest levels of CD271 in BM. Sub-clustering identified 99 genes differentially expressed among CD271high and CD271low (p < 0.05) BM-subgroups. Comparative analysis of subsets revealed increased ( ≥ 1.5fold, log2) expression of migration-associated genes and enrichment of CD271-responsible genes involved in DNA-repair and stemness. Live cell-imaging based scratch-wound assays of melanoma cells with stable knock-down of CD271 revealed a significantly reduced cell migration (3.9fold, p = 1.2E-04) and a reduced expression of FGF13, CSPG4, HMGA2 and AKT3 major candidate regulatory genes of melanoma cell migration. In summary, we provide new insights in melanoma cell migration and suggest that CD271 serves as a candidate regulator, sufficient to determine cellular properties of melanoma brain metastatic cells.

PLA is an injectable filler substance that may cause subcutaneous nodules in treated patients. Our data support a decreased risk of adverse reactions with an increased dilution. However, nodule formation still appears to be a characteristic feature of PLA.

Tspan8 exhibits a functional role in many cancer types including pancreatic, colorectal, oesophagus carcinoma, and melanoma. We present a first study on the expression and function of Tspan8 in breast cancer. Tspan8 protein was present in the majority of human primary breast cancer lesions and metastases in the brain, bone, lung, and liver. In a syngeneic rat breast cancer model, Tspan8+ tumours formed multiple liver and spleen metastases, while Tspan8− tumours exhibited a significantly diminished ability to metastasise, indicating a role of Tspan8 in metastases. Addressing the underlying molecular mechanisms, we discovered that Tspan8 can mediate up‐regulation of E‐cadherin and down‐regulation of Twist, p120‐catenin, and β‐catenin target genes accompanied by the change of cell phenotype, resembling the mesenchymal–epithelial transition. Furthermore, Tspan8+ cells exhibited enhanced cell–cell adhesion, diminished motility, and decreased sensitivity to irradiation. As a regulator of the content and function of extracellular vesicles (EVs), Tspan8 mediated a several‐fold increase in EV number in cell culture and the circulation of tumour‐bearing animals. We observed increased protein levels of E‐cadherin and p120‐catenin in these EVs; furthermore, Tspan8 and p120‐catenin were co‐immunoprecipitated, indicating that they may interact with each other. Altogether, our findings show the presence of Tspan8 in breast cancer primary lesion and metastases and indicate its role as a regulator of cell behaviour and EV release in breast cancer. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Metabolic reprogramming is as a hallmark of cancer, and several studies have reported that BRAF and KRAS tumors may be accompanied by a deregulation of cellular metabolism. We investigated how BRAFV600E and KRASG12V affect cell metabolism, stress resistance and signaling in colorectal carcinoma cells driven by these mutations. KRASG12V expressing cells are characterized by the induction of glycolysis, accumulation of lactic acid and sensitivity to glycolytic inhibition. Notably mathematical modelling confirmed the critical role of MCT1 designating the survival of KRASG12V cells. Carcinoma cells harboring BRAFV600E remain resistant towards alterations of glucose supply or application of signaling or metabolic inhibitors. Altogether these data demonstrate that an oncogene-specific decoupling of mTOR from AMPK or AKT signaling accounts for alterations of resistance mechanisms and metabolic phenotypes. Indeed the inhibition of mTOR in BRAFV600E cells counteracts the metabolic predisposition and demonstrates mTOR as a potential target in BRAFV600E-driven colorectal carcinomas.

Adverse reactions to this methacrylate filler are common. The mean latency period for these mostly severe rated reactions was nearly 2 years. Based on the frequency and severity of these reactions, the use of this filler does not seem to be advisable.

Background Pancreatic neuroendocrine neoplasms (PanNENs) fall into two subclasses: the well-differentiated, low- to high-grade pancreatic neuroendocrine tumors (PanNETs), and the poorly-differentiated, high-grade pancreatic neuroendocrine carcinomas (PanNECs). While recent studies suggest an endocrine descent of PanNETs, the origin of PanNECs remains unknown. Methods We performed DNA methylation analysis for 57 PanNEN samples and found that distinct methylation profiles separated PanNENs into two major groups, clearly distinguishing high-grade PanNECs from other PanNETs including high-grade NETG3. DNA alterations and immunohistochemistry of cell-type markers PDX1, ARX, and SOX9 were utilized to further characterize PanNECs and their cell of origin in the pancreas. Results Phylo-epigenetic and cell-type signature features derived from alpha, beta, acinar, and ductal adult cells suggest an exocrine cell of origin for PanNECs, thus separating them in cell lineage from other PanNENs of endocrine origin. Conclusions Our study provides a robust and clinically applicable method to clearly distinguish PanNECs from G3 PanNETs, improving patient stratification.

Expression of the epidermal growth factor ligands amphiregulin (AREG) and epiregulin (EREG) is positively correlated with a response to EGFR‐targeted therapies in colorectal cancer. Gene‐body methylation sites, which show a strong inverse correlation with AREG and EREG gene expression, were identified in cell lines using targeted 454 FLX‐bisulfite sequencing and SIRPH analyses for AREG/EREG promoters and intragenic CpGs. Upon treatment of colorectal cancer cells with 5‐aza‐2′‐desoxycytidine, methylation decreases at specific intragenic CpGs accompanied by upregulation of AREG and EREG gene expression. The same AREG gene‐body methylation was also found in human colorectal cancer samples and is independent of KRAS and NRAS mutations. Methylation is specifically decreased in the tumor epithelial compartment as compared to stromal tissue and normal epithelium. Investigation of a promoter/enhancer function of the AREG exon 2 region revealed a potential promoter function in reverse orientation. Retrospective comparison of the predictive power of AREG gene‐body methylation versus AREG gene expression using samples from colorectal cancer patients treated with anti‐EGFR inhibitors with complete clinical follow‐up revealed that AREG expression is superior to AREG gene methylation. AREG and EREG genes undergo a complex regulation involving both intragenic methylation and promoter‐dependent control.

The transcription factor YBX1 can act as a mediator of signals transmitted via the EGFR–RAS–MAPK axis. YBX1 expression has been associated with tumor progression and prognosis in multiple types of cancer. Immunohistochemical studies have revealed dependency between YBX1 expression and individual EGFR family members. We analyzed YBX1 and EGFR family proteins in a colorectal cancer (CRC) cohort and provide functional analyses of YBX1 in the context of EGFR–RAS–MAPK signaling. Immunohistochemistry for YBX1 and EGFR family receptors with two antibodies for YBX1 and EGFR were performed and related to clinicopathological data. We employed Caco2 cells expressing an inducible KRASV12 gene to determine effects on localization and levels of YBX1. Mouse xenografts of Caco2-KRASV12 cells were used to determine YBX1 dynamics in a tissue context. The two different antibodies against YBX1 showed discordant immunohistochemical stainings in cell culture and clinical specimens. Expression of YBX1 and EGFR family members were not correlated in CRC. Analysis of Caco2 xenografts displayed again heterogeneity of YBX1 staining with both antibodies. Our results suggest that YBX1 is controlled via complex regulatory mechanisms involving tumor stroma interaction and signal transduction processes. Our study highlights that YBX1 antibodies have different specificities, advocating their use in a combined manner.