Oncogenic Viruses Target Tumor Suppressors
Oncogenic virus infections such as hepatitis C virus, human papillomavirus (HPV), Kaposi's sarcoma herpesvirus, and human T-cell leukemia virus 1 infections, are well known causitive factors of hepatocllular carcinoma, lymphoma, and leukemia respectively.
The role of the Rb-E2F pathway in viral infection and anti-viral host defense is poorly understood. Of all E2Fs regulated y pRB, E2F1 may play a primary role in viral response by the cell cycle machinery. Although usually introduced as an "activator" E2F, E2F1 is equally capable of repressing targets in both pRB-dependent and independent manners. Examples of genes suppressed by E2F1 include vascular endothelial factor A, human telomerase reverse transcriptase, the anti-apoptotic protein Mcl-1, endoplasmic reticulum chaperone GRP78/Bip, and IRF3.
Double-stranded RNA (dsRNA) is an intermediate component during viral replication in host cells that is recognized by host innate immune molecules, including TLR3, protein kinase receptor (PKR), RIG-I and MDA5. These sensing molecules induce immune responses such as cytokine and chemokine production, which is intergral in initial anti-viral host defense in both innate and adaptive immunity.
Oncogenic virus infections such as hepatitis C virus, human papillomavirus (HPV), Kaposi's sarcoma herpesvirus, and human T-cell leukemia virus 1 infections, are well known causitive factors of hepatocllular carcinoma, lymphoma, and leukemia respectively.
The role of the Rb-E2F pathway in viral infection and anti-viral host defense is poorly understood. Of all E2Fs regulated y pRB, E2F1 may play a primary role in viral response by the cell cycle machinery. Although usually introduced as an "activator" E2F, E2F1 is equally capable of repressing targets in both pRB-dependent and independent manners. Examples of genes suppressed by E2F1 include vascular endothelial factor A, human telomerase reverse transcriptase, the anti-apoptotic protein Mcl-1, endoplasmic reticulum chaperone GRP78/Bip, and IRF3.
Double-stranded RNA (dsRNA) is an intermediate component during viral replication in host cells that is recognized by host innate immune molecules, including TLR3, protein kinase receptor (PKR), RIG-I and MDA5. These sensing molecules induce immune responses such as cytokine and chemokine production, which is intergral in initial anti-viral host defense in both innate and adaptive immunity.