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 hp
Sign In
Advertise with Us

QIAGEN

Qiagen is a provider of sample and assay technologies for molecular diagnostics and applied testing, including comple... read more Featured Products: More products

Download Mobile App




Homologous Recombination Defects Prevalent in African-American Cancer Patients

By LabMedica International staff writers
Posted on 28 Jan 2020
In the USA, African-Americans have the highest cancer incidence and lowest survival across multiple cancer types. More...
The reasons for these persistent trends are not clear.

Lung cancer, the second most common cancer in the USA and the leading cause of cancer-related death, has persistent disparities in both incidence and mortality African-Americans have the highest lung cancer incidence and mortality rates compared with other racial or ethnic groups.

Scientists from the National Cancer Institute (Bethesda, MD, USA) and their associates generated and compared genome-wide copy number profiles for 222 non-small cell lung cancer samples obtained from 126 African-American and 96 European-American patients.

DNA was extracted from fresh, frozen micro-dissected primary lung tumor tissues using the Qiagen DNeasy Blood and Tissue kit spin column procedure (Qiagen, Hilden, Germany). Isolated primary lung tumor DNA was initially quantified using a DS-11 spectrophotometer (DeNovix, Wilmington, DE, USA). Subsequent Qubit fluorometer (Thermo Fisher Scientific, Waltham, MA, USA) analyses were performed to assess DNA integrity and ensure the presence of intact double-stranded DNA in all samples.

The team estimated the tumors' genomic instability by determining the portion of their genomes that harbored a non-diploid copy number. They found that lung squamous cell carcinomas from African-Americans had higher genomic instability compared to those from European Americans. They did not, however, uncover significantly higher genomic instability in lung adenocarcinomas from American Americans, as compared to European Americans.

The team extended their analysis to 6,492 tumors from The Cancer Genome Atlas to find that tumors from African-American patients had a higher burden of genomic instability as well as of homologous recombination deficiencies. In particular, 11 of the 17 cancer types analyzed exhibited higher homologous recombination deficiency in African-Americans. Additionally, a mutational signature associated with homologous recombination deficiency was more prevalent among these tumors. In both a pan-cancer analysis and a lung squamous cell carcinoma-specific one, they found that African-American patients had significantly higher germline homologous recombination deficiencies than European-American patients. Pan-cancer, they found pathogenic variants in BRCA2, PALB2, and BARD1, among other genes, to be enriched in African-American patients.

Higher homologous recombination deficiency in lung squamous cell carcinoma and other cancers hints that these tumors could potentially respond to poly ADP ribose polymerase (PARP) inhibitors and that African-American patients in particular might be more likely to respond to PARP inhibitor treatments. While PARP inhibitors are not commonly used to treat lung cancer, the scientists noted, they have been shown in some studies to be effective in combination with chemotherapy. The study was published on January 13, 2020 in the journal Nature Cancer.

Related Links:
National Cancer Institute
Qiagen
DeNovix
Thermo Fisher Scientific



Gold Member
Quantitative POC Immunoassay Analyzer
EASY READER+
Collection and Transport System
PurSafe Plus®
New
Laboratory Software
ArtelWare
New
Clinical Chemistry System
P780
Read the full article by registering today, it's FREE! It's Free!
Register now for FREE to LabMedica.com and get access to news and events that shape the world of Clinical Laboratory Medicine.
  • Free digital version edition of LabMedica International sent by email on regular basis
  • Free print version of LabMedica International magazine (available only outside USA and Canada).
  • Free and unlimited access to back issues of LabMedica International in digital format
  • Free LabMedica International Newsletter sent every week containing the latest news
  • Free breaking news sent via email
  • Free access to Events Calendar
  • Free access to LinkXpress new product services
  • REGISTRATION IS FREE AND EASY!
Click here to Register








Channels

Hematology

view channel
Image: New research points to protecting blood during radiation therapy (Photo courtesy of 123RF)

Pioneering Model Measures Radiation Exposure in Blood for Precise Cancer Treatments

Scientists have long focused on protecting organs near tumors during radiotherapy, but blood — a vital, circulating tissue — has largely been excluded from dose calculations. Each blood cell passing through... Read more

Immunology

view channel
Image: The VENTANA HER2 (4B5) test is now CE-IVDR approved (Photo courtesy of Roche)

Companion Diagnostic Test Identifies HER2-Ultralow Breast Cancer and Biliary Tract Cancer Patients

Breast cancer is the most common cancer in Europe, with more than 564,000 new cases and 145,000 deaths annually. Metastatic breast cancer is rising in younger populations and remains the leading cause... Read more

Technology

view channel
Image: Conceptual design of the CORAL capsule for microbial sampling in the small intestine (H. Mohammed et al., Device (2025). DOI: 10.1016/j.device.2025.100904)

Coral-Inspired Capsule Samples Hidden Bacteria from Small Intestine

The gut microbiome has been linked to conditions ranging from immune disorders to mental health, yet conventional stool tests often fail to capture bacterial populations in the small intestine.... Read more
Copyright © 2000-2025 Globetech Media. All rights reserved.