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Chapter 43: Human Cancer Viruses
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Viruses can cause cancer in animals and humans. A principle of viral carcinogenesis is that
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(A) Retroviruses cause most types of human cancer.
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(B) Not all infections with a human cancer virus lead to tumor formation.
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(C) Short latent periods elapse between time of virus infection and tumor appearance.
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(D) Animal models seldom predict cellular mechanisms in human cancer.
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(E) Host factors are insignificant in influencing the development of virus-induced human cancer.
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Cellular oncogenes represent activated genes involved in cancer. A second class of cancer genes is involved in cancer development only when both alleles of such a gene are inactivated. The second class of genes is called
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(C) Tumor suppressor genes
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A 38-year-old woman is diagnosed with cervical cancer. This cancer is common worldwide and has a sexually transmitted viral etiology. The causative agent of human cervical cancer is
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(C) Human papillomaviruses, high-risk types
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Retroviruses encode an enzyme called reverse transcriptase. The function of the reverse transcriptase enzyme is
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(B) RNA-dependent DNA polymerase activity
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(C) DNA-dependent RNA polymerase activity
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(D) RNA-dependent RNA polymerase activity
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(E) Topoisomerase activity
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Two months after a kidney transplant, a 47-year-old man developed nephropathy. Up to 5% of renal allograft recipients develop nephropathy. A viral cause of some of the nephropathy cases has been identified as
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(B) Human papillomavirus, all types
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(C) Human papillomavirus, low-risk types
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(E) Human cytomegalovirus
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Human papillomavirus can cause cancer in humans and is most commonly associated with
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