We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
We use cookies to distinguish you from other users and to provide you with a better experience on our websites. Close this message to accept cookies or find out how to manage your cookie settings.
Published online by Cambridge University Press: 07 December 2009
Cell growth, differentiation and death are controlled by genes. Mechanisms are needed for both stimulating and suppressing growth. Breakdown in the mechanism for control of cell growth leads to uncontrolled growth and malignancy. There are many ways in which cells may lose this genetic control, viral infections being one of those. Not all viruses are oncogenic (e.g. able to induce cancer). It is mainly, though not exclusively, the DNA viruses that have this potential. Human T-cell leukaemia virus types 1 and 2, and hepatitis C virus are examples of RNA viruses that are able to induce malignancy.
How do viruses cause cancer?
There are several mechanisms by which this may occur.
Some viruses, such as HTLV 1, possess a viral oncogene or v-onc gene. Integration of viral genome into the infected cell enables the v-onc gene to be activated. Products of this activated v-onc gene are able to transform the cell by affecting the function of cellular products normally responsible for cell growth. It is believed that v-onc genes have been acquired by viruses through capturing cellular gene material during the process of evolution.
Oncogenes are not unique to viruses, they also form part of the normal cellular genetic material. Cellular oncogenes are different in their structure to v-onc and are referred to as c-onc to differentiate them from viral oncogenes. The c-onc products are required for normal cell activities.
Mutation in the c-onc gene is an important mechanism for cell transformation.
To save this book to your Kindle, first ensure no-reply@cambridge.org is added to your Approved Personal Document E-mail List under your Personal Document Settings on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part of your Kindle email address below. Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations. ‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi. ‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Find out more about the Kindle Personal Document Service.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Dropbox.
To save content items to your account, please confirm that you agree to abide by our usage policies. If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account. Find out more about saving content to Google Drive.
