Cancer as an Infectious Disease

Peyton Rous research

removed sarcoma from a chicken inject it into different chicken and induce cancer

how did Peyton Rous impact cancer cell research

RSV capable of multiplying in tumor

reinforced idea of cancer as infectious agent

RSV effect on chickens

RSV parasitized chicken embryo fibroblast, forcing them to produce a steady stream of virus progeny for days week, months

Usually viruses quicker

What does RSV do to culture cells

Transform normal cell to cancer cell

temperature sensitive mutant of RSV

temperature sensitive mutants encode partially defective proteins which lose function at certain temperature

How does HPV cause cancer?

Viral tumor suppressor gene E2 discarded

E2 represses transcription of viral E6 and E7 genes

E6 inhibits p53 tumor suppressor

E7 inhibits Rb tumor suppressor

How does RSV cause cancer?

uses reverse transcriptase to make DNA version of RNA virus

also carries integrase gene for chromosomal integration

Src gene

a normal proto-oncogene present in many organisms, but viral Src is a mutated oncogene that causes cancer

How does ALV induce leukemia?

insertional mutagenesis mutates proto-oncogenes

Bacterial cancer

Early H pylori infections causes gastric carcinomas

hit and run