Characterization of an animal model of aggressive metastatic pheochromocytoma linked to a specific gene signature

Abstract

Pheochromocytomas are chromaffin cell-derived neuroendocrine tumors. There is presently no cure for metastatic pheochromocytoma and no reliable way to distinguish malignant from benign tumors before the development of metastases. In order to successfully manage pheochromocytoma, it is necessary to better understand the biological determinants of tumor behavior. For this purpose, we have recently established a mouse model of metastatic pheochromocytoma using tail vein injection of mouse pheochromocytoma (MPC) cells. We optimized this model modifying the number of cells injected, length of trypsin pre-treatment, and incubation temperature and duration for the MPC cells before injection, and by serial passage and re-selection of tumors exhibiting the metastatic phenotype. We evaluated the effect of these modifications on tumor growth using serial in vivo Magnetic Resonance Imaging studies. These results show that number of cells injected, the pre-injection incubation temperature, and duration of trypsin treatment are important factors to produce faster growing, more aggressive tumors that yielded secondary metastatic lesions. Serial harvest, culture and re-selection of metastatic liver lesions produced even more aggressive pheochromocytoma cells that retained their biochemical phenotype. Microarray gene expression comparison and quantitative real-time PCR of these more aggressive cells to the MPC-parental cell line identified genes that may be important for the metastatic process.

Role of microenvironment on neuroblastoma SK-N-AS SDHB-silenced cell metabolism and function

“…For glucose and lactate uptake, each experiment was conducted in triplicate samples. ganglionic cells; they derive from a rather immature human neural phenotype (it should be remembered that SDHx as well as other mutations are germline and therefore modify cell functions beginning at a very early embryonic stage); and they are WT for all of the currently known PGL susceptibility genes (as opposed to animal cell lines such as PC12, MPC, and MTT) (Greene & Tischler 1976, Powers et al 2000, Martiniova et al 2009). Finally, the only human PHEO cell line (hPheo1) described to date (Ghayee et al 2013) is not commercially available and was obtained from a primary culture of an adrenergic cluster 2-pertaining PHEO that is immortalized by hTERT viral transfection, which therefore drives its growth potential.…”

Combined blockade of signalling pathways shows marked anti-tumour potential in phaeochromocytoma cell lines

“…2000) and mouse tumour tissue-derived (MTT; MTT-derived, more aggressive; Martiniova et al . 2009), were kindly provided by Dr Karel Pacak (NIH, Bethesda, MD, USA) and cultured in DMEM medium (Sigma, D6429) containing 10 ml/100 ml foetal bovine serum (FBS; Biosera, FB-1090/500, Labtech International, East Sussex, UK) and 50 units/ml penicillin/50 μg/ml streptomycin (Sigma, P4458) at 37 °C in a 5% CO 2 atmosphere.…”

“…For this purpose, we used two mouse PCC cell lines generated from heterozygous Nf1 knockout mice (Powers et al . 2000, 2007, Martiniova et al . 2009).…”

Malignant pheochromocytomas and paragangliomas: a diagnostic challenge

“…By comparing microarray gene expression of parental mouse PCC cells and more aggressive cells, several genes which may be important for this metastatic process have been identified, e.g. Fyn-related kinase (FRK) and keratin 8 (KRT8) ( Table 1) [200]. In this model, however, the expression of many genes was very different in human tissues compared to mouse tissue, showing the difficulties of drawing direct conclusions from animal models.…”