Cancer education
Resource for Cancer education and fun search portal . Continue for our current list for the Cancer education
Love Poems, Love Calculator
Arts And Entertainment
Health And Fitness
Home Based Business
Self Improvement
Dating, Love, Sexuality
Relationships
Funny Pictures
MSN Nick Names,Display Pictures,Emoticons,Background
In cellular model systems, cells are exposed to carcinogenic influences (chemicals, radiation). In these systems, the first signs of a cell developing into a tumor cell are:
- Immortality. The usual number of cell divisions for a mammalian cell is 50-60 (cell senescence), then it ceases to divide. Tumor cells keep dividing forever.
- Altered morphology.
- Building of cellular clusters (Foci).
- Loss of contact inhibition.
- Low or no need for growth factors.
Items 2-4 (above) can sometimes be traced to mutations in genes that result in a disruption of cell adhesion. Some cell adhesion proteins are oncogenes.
Cancers are capable of spreading through the body by two mechanisms: local invasion and distant metastasis. Invasion refers to the direct migration and penetration by cancer cells into neighboring tissues. Metastasis refers to the ability of cancer cells to penetrate into lymphatic and blood vessels, circulate through the bloodstream, and then invade normal tissues elsewhere in the body. Cancer is most deadly when it metastasizes.
For most of the cancers, it cannot be told which event was the initial cause. However, with molecular biology, it is possible to characterize the mutations within a tumor, and to a certain extent predict its behavior. For example, about half of the tumors are deficient in the tumor suppressor gene p53, also known as "the guardian of the genome". This is associated with poor prospects for the patient, since those tumor cells are unlikely to go into apoptosis (programmed cell death) after they are damaged by therapy. There are more mutations that make a tumor more malignant. Telomerase mutations enable a tumor cell to divide indefinitely. Other mutations enable the tumor to grow new blood vessels to feed it, or to detach from the surrounding tissue, spreading to other parts of the body.
- Arts And Entertainment
- Automotive
- Business
- Cancer
- Communications
- Computers And Technology
- Finance
- Food And Drink
- Health And Fitness
- Home And Family
- Home Based Business
- Internet And Businesses Online
- Kids And Teens
- Legal
- News And Society
- Recreation And Sports
- Reference And Education
- Self Improvement
- Shopping And Product Reviews
- Travel And Leisure
- Women's Interests
- Writing And Speaking
- Don't Say That Word
Provides an online forum on cancer, information, personal stories, poetry and remembrance pages. Graphics-intensive. - OncoLink
Extensive information including news, prevention, clinical trials, conferences and psychosocial support from the University of Pennsylvania Cancer Center. - CancerSupport UK
An online directory of resources. - CancerSupportChat.org
Presents access to online discussion, chat and support. - ZoeMed.com: Cancer Life Center
Presents an array of resources. Supported in partnership by the Ortho Biotech pharmaceutical firm.