Clinical trial NCT02331966: Molecular Pathways Involved in the Pathogenesis and Behavior of Mesenchymal Phosphaturic Tumors Causing Oncogenic Osteomalacia
Official title: Molecular Pathways Involved in the Pathogenesis and Behavior of Mesenchymal Phosphaturic Tumors
Study type: OBSERVATIONAL
Overall status: UNKNOWN
Conditions: Tumor Induced Oncogenic Osteomalacia
Keywords: FGF-23
GROWTH FACTORS RECEPTORS
RECURRENCES
Lead sponsor: AHEPA University Hospital
Sponsor class: OTHER
First posted: 2015-01-06
Enrollment: 10
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_ONLY
Time perspective: PROSPECTIVE
Sampling method: PROBABILITY_SAMPLE
Study population: Patients with tumor induced osteomalacia

Brief summary: The tumors that cause oncogenic osteomalacia (TIO) express and release in the circulation phosphaturic factors such as fibroblast growth factor-23 (FGF-23) that decrease renal phosphate absorption through acting in the proximal renal tubule and decreasing Type 2a and 2c sodium-phosphate co-transporter. They typically follow a benign clinical course and even in the rare malignant cases, local recurrence occurs in less than 5% and distant metastasis are very uncommon.

In this study we aim to investigate the role of other molecular pathways such as ERK1, ERK2, mTOR, EGFR, MEK1, MEK2, VEGFR3, AKT1, AKT2, IGFR-1, IGFR-2, PDGFRA, PDGFRB, cMET, FGFR2, apart from FGF23, KLOTHO and PHEX, in the behavior of histopathologically benign mesenchymal phosphaturic tumors.

Detailed description: Study Protocol Cell Culture Bone marrow and tissue samples will be obtained from the patients after they will give their written informed consent. Material will be maintained in RPMI culture medium (Sigma, R0883, Germany). Peripheral blood mononuclear cells (PBMCs) from healthy donors will be used as control. For detection of cancer cells in our samples we perform flow cytometry using EpCAM magnetic beads (39-EPC-50; Gentaur), and the negative selection cells (non-cancerous) are isolated and then cultured in a 25-cm2 flask (5520100; Orange Scientific) with RPMI-1640 medium (R6504; Sigma).

Molecular analysis RNA is extracted from cell cultures using RNeasy Mini Kit (74105; Qiagen, Hilden; Germany). iScript cDNA synthesis kit (1708891; Bio-Rad, CA; USA), is used for cDNA synthesis and Real-time polymerase chain reaction (PCR), is performed using the iTaq Universal SYBR Green Supermix (1725124; Bio-Rad). Specific primers for each marker and for an endogenous control gene (18S rRNA) is designed using Genamic Expression 1.1 software. A universal Reference RNA consisting of 10 human cancer cell lines (740000-41; Agilent) as well as human genomic DNA (G304A; Promega) will be used in quantitative PCR (qPCR) reactions Statistical analysis The qPCR results will be tested according to the Kolmogorov-Smirnov test; All the reactions (molecular assays, flow cytometry) are performed in triplicates. A p value \<0.05 is considered significant.

Eligibility criteria: Inclusion Criteria:

Patients with tumor induced osteomalacia

Exclusion Criteria:

None

Primary outcomes:
measure: Differential expression of Molecular pathways in tumors inducing oncogenic osteomalacia
timeFrame: 2 years
Secondary outcomes:
Other outcomes:
Locations:
city: Thessaloniki
country: Greece
facility: 1st Department of Internal Medicine AHEPA University Hospital
Study officials:
affiliation: AHEPA University Hospital
name: Maria P. Yavropoulou, M.D
role: PRINCIPAL_INVESTIGATOR
References: