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Thymidine Kinase 1 in Risk Assessment for Hereditary Breast /Ovarian Cancer

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00855998
Recruitment Status : Unknown
Verified March 2009 by Hadassah Medical Organization.
Recruitment status was:  Recruiting
First Posted : March 5, 2009
Last Update Posted : June 3, 2010
Information provided by:
Hadassah Medical Organization

Brief Summary:
This study aimed to compare the activity of Thymidine Kinase 1 in serum of two groups of woman at high and normal risk for breast/ovary cancer.

Condition or disease
Breast Cancer Ovarian Cancer

Detailed Description:

Hereditary breast/ovarian cancer syndrome is associated with mutations in tumor suppressor BRCA1 and BRCA2 genes. Products of these genes play an important role in the repair of DNA double-strand breaks. Mutations in BRCA1 and BRCA2 genes could impair DNA repair. In resting or G1 cells, where the de novo synthesis of DNA precursors is absent, the salvage pathway is the sole provider of deoxyribonucleotides to be used in DNA repair. For this process a sufficient supply of deoxynucleotides and activity of Thymidine Kinase 1 are essential. TK1 is an important component of adaptive response of cells to DNA damage. Mutations in genes directly engaged in the DNA repair process could lead to the accumulation of DNA damage and in turn cause an adaptive cell reaction manifesting as permanently increased Thymidine Kinase 1 activity.

A recently developed new high-sensitive assay DiviTum® allows to investigate the contribution of this enzyme to DNA repair processes and to make a comparison of Thymidine kinase 1 activity in women with normal and impared DNA repair system.

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Study Type : Observational
Estimated Enrollment : 300 participants
Observational Model: Family-Based
Time Perspective: Prospective
Official Title: Thymidine Kinase 1 in Risk Assessment for Hereditary Breast /Ovarian Cancer
Study Start Date : March 2009
Estimated Primary Completion Date : March 2010
Estimated Study Completion Date : March 2011

With BRCA1 or BRCA2 mutations
Without BRCA1 or BRCA2 mutations

Biospecimen Retention:   Samples Without DNA

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
women visiting the outpatient oncology clinic for genetic/familial high-risk assessments

Inclusion Criteria:

  • women from family with more than two breast cancer cases and one or more cases of ovarian cancer diagnosed at any age;
  • women from family with more than three breast cancer cases diagnosed before the age 50;
  • women from family withsister pair in which one of the following combinations was diagnosed before the age of 50: two breast cancers, two ovarian cancers, or a breast and ovarian cancer.

Exclusion Criteria:•

  • pregnant women;
  • women with generalized CMV and HZV infections;
  • women with severe B12 deficiency and megaloblastic anaemia;
  • women with severe rheumatoid arthritis.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00855998

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Contact: Tamar Peretz, MD 6777825 ext 00 972 2
Contact: Hadas Lemberg, PhD 6777572 ext 00 972 2

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Hadassah Medical Organization Recruiting
Jerusalem, Israel, 91120
Contact: Arik Tzukert, DMD    6776095 ext 00 972 2   
Sub-Investigator: Benjamin Nisman, PhD         
Sponsors and Collaborators
Hadassah Medical Organization
Publications automatically indexed to this study by Identifier (NCT Number):
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Responsible Party: Prof. Tamar Peretz, Head of Oncology Department, Hadassah Medical Organization Identifier: NCT00855998    
Other Study ID Numbers: 044608-HMO-CTIL
First Posted: March 5, 2009    Key Record Dates
Last Update Posted: June 3, 2010
Last Verified: March 2009
Keywords provided by Hadassah Medical Organization:
Thymidine Kinase 1
BRCA1 and BRCA2 mutations
hereditary breast/ovarian cancer
Additional relevant MeSH terms:
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Ovarian Neoplasms
Carcinoma, Ovarian Epithelial
Endocrine Gland Neoplasms
Neoplasms by Site
Ovarian Diseases
Adnexal Diseases
Genital Neoplasms, Female
Urogenital Neoplasms
Endocrine System Diseases
Gonadal Disorders
Neoplasms, Glandular and Epithelial
Neoplasms by Histologic Type