Mouse Models of Helicobacter-Induced Gastric Cancer: Use of Cocarcinogens

The human pathogen
Helicobacter pylori
causes inflammation in the stomach of infected hosts, leading in some cases to the development of gastric cancer. Several mouse models have been developed to study
Helicobacter
-induced carcinogenesis with similarities to gastric adenocarcinoma and mucosa-associated lymphoid tissue lymphoma (MALToma) in humans. These models require chronic infection of animals with mouse-colonizing isolates of
H. pylori
or with related gastric
Helicobacter
spp., such as the canine/feline species
Helicobacter felis
. Furthermore, consistent with the known influence of host and environmental factors in human gastric cancer, it is possible to manipulate the type and severity of gastric lesions in mouse
Helicobacter
infection models through the use of different mouse genetic backgrounds and/or by the administration of known cocarcinogens, such as alkylating agents (e.g.,
N
-nitroso-
N
-methylurea), or even elevated quantities of dietary salt. Here, we describe protocols for the inoculation of mice with gastric
Helicobacter
spp. and the administration of these cocarcinogens. Furthermore, we will describe the various methodologies used to study gastric inflammation and carcinogenesis in
Helicobacter
-infected animals.