The etiology of oral squamous cell carcinoma (OSCC) is complex and involves many factors. The most clearly defined risk factors are smoking and alcohol, which substantially increase the risk of oral SCC. However, despite this clear association, a substantial proportion of patients develop OSCC without exposure to them, emphasizing the role of other risk factors such as genetic susceptibility an...

Oncogenic mink cell focus-forming (MCF) viruses, such as MCF 247, show a positive correlation between the ability to replicate efficiently in the thymus and a leukemogenic phenotype. Other MCF viruses, such as MCF 30-2, replicate to high titers in thymocytes and do not accelerate the onset of leukemia. We used these two MCF viruses with different biological phenotypes to distinguish the effect ...

Several natural RNAs were compared with respect to their template activities for the DNA polymerase of Rous Sarcoma Virus during a 2-hr incubation period. 60-70S viral RNA was found to be a 5- to 10-fold better template than heat-dissociated Rous viral RNA, influenza virus RNA, tobacco mosaic virus RNA, or ribosomal RNA. Denatured salmon DNA is a little better, and poly(dAT) is 2-4 times better...

The RNA of a deleted strain (lacking Src gene) of an avian sarcoma virus (ASV) was examined by a newly developed immunoelectron microscopic procedure which uses anti-nucleotide antibodies as probes. After denaturation of the RNA and reaction with a high affinity, highly specific anti-7-methylguanosine-5'-phosphate (anti-pm 7G), 81% of 106 molecules examined were found to have antibody at one te...

The papillomavirus E2 proteins regulate viral transcription and replication and therefore play a central role in the viral life-cycle. In BPV1, the full-length E2 gene product is a transcriptional transactivator that activates transcription from several viral promoters by binding to E2 binding sites located within enhancer elements in the LCR (reviewed in [68,75]). BPV1 also encodes two shorter...

Approximately 20% of human cancers is attributable to DNA oncogenic viruses such as human papillomavirus (HPV), hepatitis B virus (HBV), and Epstein-Barr virus (EBV). Unrepaired DNA damage is the most common and overlapping feature of these DNA oncogenic viruses and a source of genomic instability and tumour development. Sustained DNA damage results from unceasing production of reactive oxygen ...

Infectious agents, mainly viruses, are among the few known causes of cancer and contribute to a variety of malignancies worldwide. The agents and cancers considered here are human papillomaviruses (cervical carcinoma); human polyomaviruses (mesotheliomas, brain tumors); Epstein-Barr virus (B-cell lymphoproliferative diseases and nasopharyngeal carcinoma); Kaposi's Sarcoma Herpesvirus (Kaposi's ...