Hypertension in NF1: A closer look at the primacy of essential hypertension versus secondary causes.

BACKGROUND: We aimed to analyze hypertension in neurofibromatosis type 1 (NF1) in a Finnish population-based cohort in 1996-2014. METHODS: A cohort of 1365 individuals with confirmed NF1 was compared with a control cohort of 13,923 individuals matched for age, sex, and area of residence. Diagnoses of hypertension were retrieved from the Finnish Care Register for Health Care. These registered data were separately analyzed for secondary and essential hypertension. Purchases of antihypertensive drugs were queried from the Finnish Register of Reimbursed Drug Purchases. RESULTS: We identified 115 NF1 patients with hospital diagnosis of hypertension. Our findings revealed a hazard ratio (HR) of 1.64 (95% CI 1.34-2.00, p < 0.001) in NF1 versus controls. NF1 patients presented with a significantly increased hazard for both secondary hypertension (n = 9, HR 3.76, 95% CI 1.77-7.95, p < 0.001) and essential hypertension (n = 98, HR 1.73, 95% CI 1.39-2.14, p < 0.001). No difference in the HR of hypertension was observed between men and women, while NF1 patients with essential hypertension were, on average, younger than the controls. The proportions of individuals with antihypertensive medication did not differ between NF1 patients and controls (OR 0.85). CONCLUSION: NF1 is a risk factor for hypertension. Despite the recognized risk for secondary hypertension, essential hypertension is the predominant type in NF1.

Intestinal tumors in neurofibromatosis 1 with special reference to fatal gastrointestinal stromal tumors (GIST).

BACKGROUND: Type 1 neurofibromatosis (NF1) is a genetic tumor predisposing Rasopathy. NF1 patients have an increased risk for developing benign and malignant tumors, but the occurrence of intestinal tumors has not been investigated at the population level. METHODS: In this retrospective register-based total population study, diagnoses of gastrointestinal tract tumors were retrieved from the Finnish Care Register for Health Care for 1,410 NF1 patients and 14,030 reference persons. We also reviewed the death certificates of 232 NF1 patients who died during years 1987-2013, and specifically searched for diagnosis of gastrointestinal stromal tumor (GIST). RESULTS: The register analysis revealed an increased overall hazard ratio (HR) of 2.6 (95% CI 1.9-3.6) for intestinal tumors in NF1 compared to general population. The highest HR of 15.6 (95% CI 6.9-35.1) was observed in the small intestine. The focused analysis of NF1 death certificates and GISTs demonstrated that the GIST was the primary cause of death in seven patients. CONCLUSION: This study emphasizes the need for careful evaluation of NF1 patients with gastrointestinal complaints. The challenge in diagnosis is that the tumors preferably occur at the small intestine, which is difficult target for diagnostic procedures. We also show that the NF1 GISTs may lead to fatal outcome despite of benign histopathological findings at the time of the diagnosis.

FGF-8b induces growth and rich vascularization in an orthotopic PC-3 model of prostate cancer.

Fibroblast growth factor 8 (FGF-8) is expressed at an increased level in a high proportion of prostate cancers and it is associated with a poor prognosis of the disease. Our aim was to study the effects of FGF-8b on proliferation of PC-3 prostate cancer cells and growth of PC-3 tumors, and to identify FGF-8b-associated molecular targets. Expression of ectopic FGF-8b in PC-3 cells caused a 1.5-fold increase in cell proliferation in vitro and a four- to fivefold increase in the size of subcutaneous and orthotopic prostate tumors in nude mice. Tumors expressing FGF-8b showed a characteristic morphology with a very rich network of capillaries. This was associated with increased spread of the cancer cells to the lungs as measured by RT-qPCR of FGF-8b mRNA. Microarray analyses revealed significantly altered, up- and downregulated, genes in PC-3 cell cultures (169 genes) and in orthotopic PC-3 tumors (61 genes). IPA network analysis of the upregulated genes showed the strongest association with development, cell proliferation (CRIP1, SHC1), angiogenesis (CCL2, DDAH2), bone metastasis (SPP1), cell-to-cell signaling and energy production, and the downregulated genes associated with differentiation (DKK-1, VDR) and cell death (CYCS). The changes in gene expression were confirmed by RT-qPCR. In conclusion, our results demonstrate that FGF-8b increases the growth and angiogenesis of orthotopic prostate tumors. The associated gene expression signature suggests potential mediators for FGF-8b actions on prostate cancer progression and metastasis.