We use cookies to understand how you use our site and to improve your experience. This includes personalizing content and advertising. To learn more, click here. By continuing to use our site, you accept our use of cookies. Cookie Policy.

Features Partner Sites Information LinkXpress
Sign In
Advertise with Us
Abbott Diagnostics- Hematology Division

Download Mobile App


ATTENTION: Due to the COVID-19 PANDEMIC, many events are being rescheduled for a later date, converted into virtual venues, or altogether cancelled. Please check with the event organizer or website prior to planning for any forthcoming event.

Serum Levels of Thymidine Kinase Predict Disease Progression and Overall Survival of Metastatic Breast Cancer Patients

By LabMedica International staff writers
Posted on 25 Sep 2021
Print article
Structure of the TK1 protein (Photo courtesy of Wikimedia Commons)
Structure of the TK1 protein (Photo courtesy of Wikimedia Commons)
Blood serum levels of the enzyme thymidine kinase 1 (TK1) have been found to predict disease progression and overall survival of patients with metastatic hormone receptor-positive breast cancer (MBC).

Previous studies have found that elevated blood serum levels of TK1 were associated with the presence of many types of malignancy and that TK1 levels were elevated in serum even before the appearance of clinical symptoms.

Based on these findings, investigators at the University of Michigan (Ann Arbor, USA) and their colleagues at other institutions assessed the prognostic effect of TK1 in patients with hormone receptor-positive MBC treated in a prospective randomized trial of single drug treatment (anastrozole [A]) compared to dual drug treatment (anastrolzole plus fulvestrant [A+F]).

For this study, the investigators assessed TK1 levels in 1,726 sera from 432 patients (base line, before the start of their treatment, and at four time points during treatment) using the Biovica International (Uppsala, Sweden) DiviTum assay.

The DiviTum assay determines the enzymatic activity of TK in human serum samples. During the assay procedure, thymidine is replaced by its synthetic analog bromodeoxyuridine (BrdU), which becomes phosphorylated and then incorporated into a synthetic DNA strand fixated in each well of a 96-well ELISA immunosorbent titer-plate. The extent of BrdU incorporation depends on the activity of TK present in the serum sample; the more TK activity in the sample, the more BrdU is incorporated into synthetic DNA strands in the titer-plate well. The synthetic BrdU is then detected with anti-BrdU specific antibodies using the ELISA assay technique. The DiviTum technology amplifies the signal, enabling the assay to measure thymidine kinase activity with high sensitivity.

Results revealed that patients with high TK1 levels, either before treatment or at any time during treatment, tended to have a significantly shorter progression-free survival time (PFS). Those with high levels at the start of treatment, or baseline, had a median PFS of 11.2 months compared to 17.3 months for patients with low levels at baseline. The high-TK1 patients also survived for a shorter period of time. On average, those patients with high levels of the biomarker had median overall survival times of 30 months compared to 58 months for those with low levels.

Patients with low TK1 levels responded well to the single drug anastrozole. This finding suggested that measurement of pre-treatment TK1 levels could potentially be used to determine whether a patient should start treatment with two-drug endocrine therapy (high TK1) or a single-drug endocrine therapy (low TK1).

Contributing author Dr. Daniel Hayes, professor of internal medicine at the University of Michigan, said, “These results should serve as the basis for future clinical studies to distinguish patients with estrogen receptor metastatic breast cancer who might be best treated with endocrine therapy alone versus those who should receive endocrine therapy plus an ancillary treatment, such as CDK4/6, mTOR, or PIK3CA inhibitors. Each of these has been shown to complement endocrine therapy, but each is associated with additional side effects and costs.”

The TK1 study was published in the September 14, 2021, online edition of the journal Clinical Cancer Research.

Related Links:

University of Michigan
Biovica International

Gold Supplier
Hemostasis Analyzer
STA R Max 3
Silver Supplier
Bacteriuria Test Strips
MAST Bacteruritest Strips
SARS-CoV-2 Antigen Immunofluorescence System
Watmind SARS-CoV-2 Antigen Immunofluorescence System
Laboratory Automation System

Print article



view channel
Image: The Gazelle Hb Variant Test for screening, diagnosis and management of sickle cell disease and related hemoglobinopathies at the point of care (Photo courtesy of Hemex Health)

Point-of-Care Device Accurately Rapidly Diagnoses Sickle Cell Disease

Hemoglobinopathies are the most common autosomal hereditary disorders. Approximately 7% of the global population carries hemoglobin gene mutation including structural hemoglobin variants like sickle hemoglobin... Read more


view channel
Image: The IMMULITE 2000 XPi Immunoassay System provides multiple tests on a single, easy-to-use analyzer, including the thyroid-stimulating immunoglobulin assay (Photo courtesy of Siemens Healthcare)

Immunoassays Evaluated for Thyroid-Stimulating Receptor Antibody in Graves’ Disease

Graves' disease (GD), also known as toxic diffuse goiter, is an autoimmune disease that affects the thyroid. It frequently results in and is the most common cause of hyperthyroidism and it also often results... Read more


view channel
Image: The sciREADER CL2 enables high quality digital colorimetric imaging of various support formats (Photo courtesy of SCIENION)

Multiplex Immunoassay Developed for Confirmation and Typing of HTLV Infections

Human T-Cell Lymphotropic Viruses (HTLV) type 1 and type 2 account for an estimated five to 10 million infections worldwide and are transmitted through breast feeding, sexual contacts and contaminated... Read more


view channel

AI Accurately Detects and Diagnoses Colorectal Cancer from Tissue Scans As Well or Better Than Pathologists

Artificial intelligence (A) can accurately detect and diagnose colorectal cancer from tissue scans as well or better than pathologists, according to a new study. The study, which was conducted by researchers... Read more


view channel
Image: PKeye Workflow Monitor System (Photo courtesy of PerkinElmer, Inc.)

PerkinElmer’s New Cloud-Based Platform Enables Laboratory Personnel to Remotely Manage Its Instruments in Real-Time

PerkinElmer, Inc. (Waltham, MA; USA) has launched its PKeye Workflow Monitor, a cloud-based platform enabling laboratory personnel to remotely manage and monitor their PerkinElmer instruments and workflows... Read more


view channel

Global Point of Care Diagnostics Market to Top USD 35 Billion by 2027 Due to Rising Diabetic Cases

The global point of care diagnostics market is projected to grow at a CAGR of close to 6% from more than USD 23 billion in 2020 to over USD 35 billion by 2027, driven by an increase in the number of diabetic... Read more
Copyright © 2000-2021 Globetech Media. All rights reserved.