Related Experiment Video
Updated: Feb 6, 2026
05:52
Sentinel Lymph Node Mapping and Biopsy for Endometrial Cancer at Early Stage with Laparoscopy
Published on: August 19, 2021
13.3K
Mutation heterogeneity between primary gastric cancers and their matched lymph node metastases
Han Hong Lee1,2, Su Young Kim3, Eun Sun Jung4
1Division of Gastrointestinal Surgery, Department of Surgery, College of Medicine, The Catholic University of Korea, Seoul, South Korea.
Summary
Gastric cancer (GC) metastasis to lymph nodes (LNs) involves distinct genetic changes. While mutation abundance is similar, specific mutations arise in primary tumors or LNs, impacting cancer evolution.
Area of Science:
- Genomics
- Cancer Biology
- Oncology
Background:
- Tumor cell invasion is key to malignancy.
- Genetic drivers of gastric cancer (GC) invasion and metastasis are poorly understood.
Purpose of the Study:
- To investigate the genetic landscape of gastric cancer metastasis to lymph nodes (LNs).
- To compare somatic alterations between primary GC and matched LN metastases.
Main Methods:
- Whole-exome sequencing of 15 primary GC and matched LN pairs.
- Analysis of single nucleotide variations, indels, microsatellite instability, and copy number alterations.
Main Results:
- Mutation abundance was similar between primary GC and LN metastases.
- Significant heterogeneity in mutation overlap and distinct primary- or LN-specific mutations were observed.
- TP53 mutations were common, while SMARCA4 and CTNNB1 mutations were region-specific.
- LN metastases likely originated from homogeneous subclones of primary tumors.
Conclusions:
- Mutation patterns offer insights into the evolutionary relationship between primary tumors and LN metastases.
- Distinguishes early cancer drivers (e.g., TP53) from late-acquired, region-specific mutations.
Related Concept Videos
01:23Detailed Structure and Function of Lymph Nodes
4.9K
Lymph nodes are bean-shaped structures that cluster along the lymphatic vessels in the inguinal, axillary, and cervical regions. Each node is divided into compartments by a capsule that extends trabeculae inward.
From a histological perspective, lymph nodes can be split into two main areas: the superficial cortex and the deep medulla. The outer cortex is populated by dendritic cells, macrophages, and B lymphocytes, which are densely packed into follicles. When these B-lymphocytes are presented...
From a histological perspective, lymph nodes can be split into two main areas: the superficial cortex and the deep medulla. The outer cortex is populated by dendritic cells, macrophages, and B lymphocytes, which are densely packed into follicles. When these B-lymphocytes are presented...
4.9K
01:39Mutations
94.5K
Overview
94.5K
01:35Mutations
44.6K
Mutations are changes in the sequence of DNA. These changes can occur spontaneously or they can be induced by exposure to environmental factors. Mutations can be characterized in a number of different ways: whether and how they alter the amino acid sequence of the protein, whether they occur over a small or large area of DNA, and whether they occur in somatic cells or germline cells.
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
Chromosomal Alterations Are Large-Scale Mutations
While point mutations are changes in a single nucleotide in...
44.6K
01:17Sign Test for Matched Pairs
417
The sign test for matched pairs offers a robust method for comparing two paired samples, often for the effects of an intervention in one of them. This method is very useful in situations where the underlying distribution of the data is unknown. The test compares two related samples—often pre- and post-treatment measurements on the same subjects—to determine if there are significant differences in their median values.
To conduct the sign test, we first calculate the differences in...
To conduct the sign test, we first calculate the differences in...
417
02:21Cancers Originate from Somatic Mutations in a Single Cell
14.9K
Cancer arises from mutations in the critical genes that allow healthy cells to escape cell cycle regulation and acquire the ability to proliferate indefinitely. Though originating from a single mutation event in one of the originator cells, cancer progresses when the mutant cell lines continue to gain more and more mutations, and finally, become malignant. For example, chronic myelogenous leukemia (CML) develops initially as a non-lethal increase in white blood cells, which progressively...
14.9K
00:36Viral Mutations
39.9K
A mutation is a change in the sequence of bases of DNA or RNA in a genome. Some mutations occur during replication of the genome due to errors made by the polymerase enzymes that replicate DNA or RNA. Unlike DNA polymerase, RNA polymerase is prone to errors because it is not capable of “proofreading” its work. Viruses with RNA-based genomes, like HIV, therefore accrue mutations faster than viruses with DNA-based genomes. Because mutation and recombination provide the raw material...
39.9K