Observing the Changes of Fibroblast Growth Factor 23 in Patients of Tumor Induced Osteomalacia

July 4, 2016 updated by: National Taiwan University Hospital

Fibroblast froth factors (FGFs) are humoral factors identified by their ability to stimulate cell proliferation1. They play different roles in the regulation of cell proliferation, differentiation and function. Most FGF family members act as paracrine factors. But FGF19(FGF19) subfamily members, including FGF19, 21, and 23, work as endocrine factors to regulate bile acid, carbohydrate and phosphate metabolism2. Of these, FGF23 plays an important role in phosphate and bone metabolism3. FGF23 gene encodes 251 amino acids, including a 24-amino acid signal peptide4. The secreted FGF23 is a protein consisted of 227 amino acids. It works by binding to a Klotho-FGF receptor 1c (FGF1c) complex5. FGF suppresses the expression of type 2a and 2c sodium-phosphate cotransporters, which mediate phosphate reabsorption in proximal tubules.6 FGF23 decreases 25-hydroxyvitamin D-1α-hydroxylase expression and enhances 25-hydroxyvitamin D-24-hydroxylase expression6. Therefore, FGF23 reduces serum 1,25-dihydroxyvitamin D〔1,25(OH)2D〕, which stimulates intestinal calcium and phosphate absorption. FGF23 decreases serum phosphate through the above mechanisms FGF23 over-expression might result in hypophosphatemic rickets and osteomalacia.

Tumor induced osteomalacia (TIO) is a paraneoplastic syndrome usually caused by benign phosphaturic mesenchymal tumors. Symptoms are nonspecific, such as general weakness, fatigue, and bone pain. Sometimes fracture may occurs. The responsible tumors are sometimes small and difficult to detect. Tumors secrete FGF23. FGF23 reduced phosphate reabsorption in the proximal tubules and decrease 1,25(OH)2D levels, which result in hypophosphatemia and then osteomalacia.

The investigators would like to observe the changes of FGF23 in patients who receive operation or medical treatment and hope this will benefit future treatment.

Study Overview

Status

Unknown

Conditions

Study Type

Observational

Enrollment (Anticipated)

40

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Taipei, Taiwan
        • Recruiting
        • National Taiwan University Hospital
        • Contact:
        • Principal Investigator:
          • Shyang-Rong Shih, PhD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

20 years to 85 years (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Patients with tumor induced osteomalacia and people without osteomalacia

Description

Inclusion Criteria:

  • patients with tumor induced osteomalacia.
  • people without osteomalacia such as healthy people,
  • people under dialysis,
  • people with poor nutrition.

Exclusion Criteria:

  • people younger than 20 years old or older than 85 years old.
  • people who are pregnant.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: Case-Control
  • Time Perspectives: Prospective

Cohorts and Interventions

Group / Cohort
Tumor induced osteomalcia

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Time Frame
FGF23, P
Time Frame: at the time TIO is diagnosed
at the time TIO is diagnosed

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Shyang-Rong Shih, PhD, National Taiwan University Hospital

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

June 1, 2011

Primary Completion (Anticipated)

August 1, 2016

Study Completion (Anticipated)

August 1, 2016

Study Registration Dates

First Submitted

August 5, 2012

First Submitted That Met QC Criteria

August 7, 2012

First Posted (Estimate)

August 8, 2012

Study Record Updates

Last Update Posted (Estimate)

July 6, 2016

Last Update Submitted That Met QC Criteria

July 4, 2016

Last Verified

July 1, 2016

More Information

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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