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
LGC Clinical Diagnostics

Thermo Fisher Scientific

Thermo Fisher Scientific Inc. serves customers who are accelerating life sciences research, solving complex analytica... read more Featured Products: More products

Download Mobile App




Events

09 Apr 2024 - 12 Apr 2024
15 Apr 2024 - 17 Apr 2024
23 Apr 2024 - 26 Apr 2024

DNA Alterations Identified Occur Earliest in Lung Cancer Development

By LabMedica International staff writers
Posted on 30 Sep 2015
Print article
Image: The NanoDrop 8000 UV-Vis Spectrophotometer (Photo courtesy of Thermo Scientific).
Image: The NanoDrop 8000 UV-Vis Spectrophotometer (Photo courtesy of Thermo Scientific).
Lungs resected for adenocarcinomas often harbor minute discrete foci of cytologically atypical pneumocyte proliferations designated as atypical adenomatous hyperplasia (AAH), which may represent an initial step in the progression to adenocarcinoma in situ (AIS).

DNA alterations in the tissue and blood of people with precancerous and cancerous lung lesions has been identified in what it believes are among the very earliest "premalignant" genetic changes that mark the potential onset of the most common and deadliest form of disease.

Scientists at Johns Hopkins University School of Medicine (Baltimore, MD, USA) collected retrospectively formalin-fixed, paraffin-embedded (FFPE) lung cancer specimens harboring multiple AAH lesions and AIS or minimally invasive adenocarcinoma (MIA) tumors. DNA was extracted from 25 distinct AAHs incidentally discovered in the lung resection specimens from six patients with invasive adenocarcinoma. Samples from AIS and MIA tumors extracted from five patients each were collected from different zones of histologic progression within the same lesion. Three or four histologically different zones were collected from each AIS and MIA samples respectively.

DNA was extracted using standard protocols and quantified with the Nanodrop system (Thermo Scientific; Wilmington, DE, USA). The CancerSelect-R panel was used to analyze the regions of 125 well-characterized cancer genes to identify tumor-specific (somatic) mutations, copy number changes and translocations. Paired-end sequencing, resulting in 150 bases from each end of the fragments, was performed using a MiSeq System (Illumina; San Diego, CA, USA). All droplet digital polymerase chain reactions (ddPCR) assays used in the study were designed and optimized to work in the ddPCR system by Bio-Rad (Hercules, CA, USA).

The team found that V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS), tumor protein p53 (TP53) and epidermal growth factor receptor (EGFR) mutations are indicators of malignant transition. Utilizing droplet digital PCR, they found alterations associated with early neoplasms in paired circulating DNA. When the team further explored different regions within the same lesion, they found genetic differences even within the same lesion. Mutations associated with good and poor prognosis or responses to therapy were seen in different regions of the same tumor, highlighting the limitations of single biopsies commonly used to decide patients' therapies.

David Sidransky, MD, a professor of oncology and pathology and senior author of the study said, “This study takes detection to a whole new level in terms of size of the lesion. I'm not aware that circulating DNA from precancerous lesions this small has ever been identified before.” As they detected the mutations in the fluids, even mutations found in only one specific zone of a lesion, Prof. Sidransky added, “That this finding may indicate that a blood or sputum test could better represent the overall composition of a tumor than a single biopsy sample.” The study was published on September 16, 2015, in the journal Nature Communications.

Related Links:

Johns Hopkins University School of Medicine 
Nanodrop 
Illumina


Platinum Member
COVID-19 Rapid Test
OSOM COVID-19 Antigen Rapid Test
Specimen Collection & Transport
POCT Fluorescent Immunoassay Analyzer
FIA Go
Gold Member
ADAMTS-13 Protease Activity Test
ATS-13 Activity Assay

Print article

Channels

Clinical Chemistry

view channel
Image: Reaching speeds up to 6,000 RPM, this centrifuge forms the basis for a new type of inexpensive, POC biomedical test (Photo courtesy of Duke University)

POC Biomedical Test Spins Water Droplet Using Sound Waves for Cancer Detection

Exosomes, tiny cellular bioparticles carrying a specific set of proteins, lipids, and genetic materials, play a crucial role in cell communication and hold promise for non-invasive diagnostics.... Read more

Hematology

view channel
Image: The low-cost portable device rapidly identifies chemotherapy patients at risk of sepsis (Photo courtesy of 52North Health)

POC Finger-Prick Blood Test Determines Risk of Neutropenic Sepsis in Patients Undergoing Chemotherapy

Neutropenia, a decrease in neutrophils (a type of white blood cell crucial for fighting infections), is a frequent side effect of certain cancer treatments. This condition elevates the risk of infections,... Read more

Pathology

view channel
Image: The OvaCis Rapid Test discriminates benign from malignant epithelial ovarian cysts (Photo courtesy of INEX)

Intra-Operative POC Device Distinguishes Between Benign and Malignant Ovarian Cysts within 15 Minutes

Ovarian cysts represent a significant health issue for women globally, with up to 10% experiencing this condition at some point in their lives. These cysts form when fluid collects within a thin membrane... Read more
Copyright © 2000-2024 Globetech Media. All rights reserved.