Stomach Cancers Separated into Four Distinct Types

Stomach cancer cells (via Wikimedia Commons)

“US researchers have shown that stomach cancer is at least four separate diseases.

“The findings, published in the journal Nature, could rapidly lead to new clinical trials focusing on the different forms. Drugs are already available that target the genetic faults behind some of them.

“Experts from The Cancer Genome Atlas Research Network – a US-wide government-funded research project – analysed 295 samples of stomach cancers to find similarities that may be targeted when developing treatments.

“Research into the biology of stomach cancer and the development of new therapies has been difficult because of the different forms that the disease can take.

“Lead author Dr Adam Bass, from the Dana-Farber Cancer Institute, said that, despite stomach cancer being a diverse disease up until now researchers had tended to take a ‘one-size-fits-all’ approach to stomach cancer treatments.”

Editor’s note: For other cancer types, including lung cancer and melanoma, doctors often prescribe drugs that are personalized according to mutations found in patients’ tumors. Learn more about personalized cancer treatment.

Image: Stomach cancer cells (via Wikimedia Commons)


A Catalog of Cancer Genes That’s Done, or Just a Start

“Cancer is a disease of genes gone wrong. When certain genes mutate, they make cells behave in odd ways. The cells divide swiftly, they hide from the immune system that could kill them, and they gain the nourishment they need to develop into tumors.

“Scientists started identifying these cancer genes in the 1970s and their list slowly grew over the years. By studying them, scientists came to understand how different types of cancer develop and, in some cases, they were even able to develop gene-targeting drugs. Last May, for example, the U.S. Food and Drug Administration approved a drug known as Tarceva to treat lung cancer in which a gene called EGFR has mutated.”


A Catalog of Cancer Genes That’s Done, or Just a Start

“Cancer is a disease of genes gone wrong. When certain genes mutate, they make cells behave in odd ways. The cells divide swiftly, they hide from the immune system that could kill them, and they gain the nourishment they need to develop into tumors.

“Scientists started identifying these cancer genes in the 1970s and their list slowly grew over the years. By studying them, scientists came to understand how different types of cancer develop and, in some cases, they were even able to develop gene-targeting drugs. Last May, for example, the U.S. Food and Drug Administration approved a drug known as Tarceva to treat lung cancer in which a gene called EGFR has mutated.”


A Catalog of Cancer Genes That’s Done, or Just a Start

“Cancer is a disease of genes gone wrong. When certain genes mutate, they make cells behave in odd ways. The cells divide swiftly, they hide from the immune system that could kill them, and they gain the nourishment they need to develop into tumors.

“Scientists started identifying these cancer genes in the 1970s and their list slowly grew over the years. By studying them, scientists came to understand how different types of cancer develop and, in some cases, they were even able to develop gene-targeting drugs. Last May, for example, the U.S. Food and Drug Administration approved a drug known as Tarceva to treat lung cancer in which a gene called EGFR has mutated.”


A Panoramic View of Cancer

“Genomics has already made great contributions to our understanding of cancer biology but, until now, has focused on characterizing individual cancer types. The Pan-Cancer Initiative of The Cancer Genome Atlas (TCGA) has now taken the next step — comparative genomic analyses across the 12 cancer types for which genomic data have so far been generated.”


A Panoramic View of Cancer

“Genomics has already made great contributions to our understanding of cancer biology but, until now, has focused on characterizing individual cancer types. The Pan-Cancer Initiative of The Cancer Genome Atlas (TCGA) has now taken the next step — comparative genomic analyses across the 12 cancer types for which genomic data have so far been generated.”


A Panoramic View of Cancer

“Genomics has already made great contributions to our understanding of cancer biology but, until now, has focused on characterizing individual cancer types. The Pan-Cancer Initiative of The Cancer Genome Atlas (TCGA) has now taken the next step — comparative genomic analyses across the 12 cancer types for which genomic data have so far been generated.”


Mutational Landscape and Significance Across 12 Major Cancer Types

“The Cancer Genome Atlas (TCGA) has used the latest sequencing and analysis methods to identify somatic variants across thousands of tumours. Here we present data and analytical results for point mutations and small insertions/deletions from 3,281 tumours across 12 tumour types as part of the TCGA Pan-Cancer effort. We illustrate the distributions of mutation frequencies, types and contexts across tumour types, and establish their links to tissues of origin, environmental/ carcinogen influences, and DNA repair defects. Using the integrated data sets, weidentified 127 significantly mutated genes fromwell-known (for example,mitogen-activated protein kinase, phosphatidylinositol-3-OH kinase,Wnt/b-catenin and receptor tyrosine kinase signalling pathways, and cell cycle control) and emerging (for example, histone, histone modification, splicing, metabolism and proteolysis) cellular processes in cancer. The average number of mutations in these significantly mutated genes varies across tumour types; most tumours have two to six, indicating that the number of driver mutations required during oncogenesis is relatively small. Mutations in transcriptional factors/regulators show tissue specificity, whereas histone modifiers are often mutated across several cancer types. Clinical association analysis identifies genes having a significant effect on survival, and investigations of mutations with respect to clonal/subclonal architecture delineate their temporal orders during tumorigenesis. Taken together, these results lay the groundwork for developing new diagnostics and individualizing cancer treatment.”


Mutational Landscape and Significance Across 12 Major Cancer Types

“The Cancer Genome Atlas (TCGA) has used the latest sequencing and analysis methods to identify somatic variants across thousands of tumours. Here we present data and analytical results for point mutations and small insertions/deletions from 3,281 tumours across 12 tumour types as part of the TCGA Pan-Cancer effort. We illustrate the distributions of mutation frequencies, types and contexts across tumour types, and establish their links to tissues of origin, environmental/ carcinogen influences, and DNA repair defects. Using the integrated data sets, weidentified 127 significantly mutated genes fromwell-known (for example,mitogen-activated protein kinase, phosphatidylinositol-3-OH kinase,Wnt/b-catenin and receptor tyrosine kinase signalling pathways, and cell cycle control) and emerging (for example, histone, histone modification, splicing, metabolism and proteolysis) cellular processes in cancer. The average number of mutations in these significantly mutated genes varies across tumour types; most tumours have two to six, indicating that the number of driver mutations required during oncogenesis is relatively small. Mutations in transcriptional factors/regulators show tissue specificity, whereas histone modifiers are often mutated across several cancer types. Clinical association analysis identifies genes having a significant effect on survival, and investigations of mutations with respect to clonal/subclonal architecture delineate their temporal orders during tumorigenesis. Taken together, these results lay the groundwork for developing new diagnostics and individualizing cancer treatment.”