LWBK1006-09 LWW-Govindan-Review December 12, 2011 18:51
Chapter 9•Principles of Immunotherapy 111Answer 9.6. The answer is D.
Expression of the Epstein-Barr virus latent gene EBNA is seen in Burkitt’s
lymphoma, nasopharyngeal carcinoma, and T cell lymphoma.Answer 9.7. The answer is C.
HPV vaccines protect women from contracting the strains of HPV that
are commonly associated with the development of cervical cancer: HPV
16 and 18. The quadrivalent HPV vaccine (Gardisil) also offers protec-
tion against HPV 6 and 11, which cause genital warts in 90% of cases.
HPV vaccination does not prevent cervical cancer in everyone, since only
70% of cervical cancer is related to HPV. If a patient already has cervical
cancer, it will not provide a tumor response, and if the patient has already
contracted HPV16 or 18, it will not offer any additional protection to the
patient.Answer 9.8. The answer is B.
Unlike HPV infections, HBV and HCV infections do not seem to pro-
duce oncogenic proteins that lead to transformation into carcinoma. It
is thought that the majority of the liver damage results from immune
responses directed against HBV-infected cells and inflammation. There is
an increased cell turnover in chronic hepatitis infections that could lead to
an increase in the amount of somatic mutations in the normal hepatocytes,
thus leading to an increased risk of carcinoma.Answer 9.9. The answer is D.
Several models have demonstrated impairment of the immune system
within the tumor microenvironment. Although the T cells within the
tumor show impairment, it has been shown that peripheral T cells do not
have the same dysfunctionality. Expression of arginase within myeloid
cells has been shown to downregulate T-cell receptor zeta-chain expres-
sion and lead to T-cell function impairment. Myeloid suppressor cells
have been discovered to secrete GM-CSF, resulting in an accumulation of
CD34+suppressor cells.Answer 9.10. The answer is D.
Three main approaches to cancer immunotherapy include nonspecific
stimulation of immune reactions through stimulation of effector cells
and/or inhibition of regulatory cells, active immunization using cancer
vaccines, and adoptive immunotherapy, defined as the passive transfer of
activated immune cells with antitumor activity.Answer 9.11. The answer is A.
When CTLA-4 is engaged on the T cell, the T-cell function is impaired.
This is an example of a nonantigen-specific therapy. When CD28 is
engaged, T cells are stimulated. B7-1 and B7-2 are ligands that are cos-
timulatory on the T cells.