OCC Targeted Therapy & Immunotherapy in Oncology 1 — Questions and Answers
Question 1: Which class of targeted therapy works by inhibiting the BCR-ABL tyrosine kinase, making it effective in chronic myeloid leukemia (CML)?
- Monoclonal antibodies
- Tyrosine kinase inhibitors (TKIs) (Correct answer)
- mTOR inhibitors
- CDK 4/6 inhibitors
Correct answer: Tyrosine kinase inhibitors (TKIs)
Tyrosine kinase inhibitors like imatinib directly block BCR-ABL, the constitutively active kinase driving CML proliferation.
Question 2: Trastuzumab (Herceptin) targets which receptor overexpressed in HER2-positive breast cancer?
- EGFR (HER1)
- HER3
- HER2/neu (ErbB2) (Correct answer)
- VEGFR-2
Correct answer: HER2/neu (ErbB2)
Trastuzumab is a monoclonal antibody that selectively binds to the extracellular domain of HER2/neu (ErbB2), inhibiting downstream proliferative signaling.
Question 3: What is the primary mechanism of action of bevacizumab (Avastin)?
- Inhibits EGFR signaling on tumor cells
- Binds circulating VEGF to prevent tumor angiogenesis (Correct answer)
- Blocks PD-1/PD-L1 immune checkpoint interaction
- Inhibits mTOR complex 1 signaling
Correct answer: Binds circulating VEGF to prevent tumor angiogenesis
Bevacizumab is an anti-VEGF monoclonal antibody that sequesters VEGF in circulation, preventing it from binding its receptors and thereby inhibiting tumor angiogenesis.
Question 4: KRAS mutations predict resistance to which targeted therapy in metastatic colorectal cancer?
- Anti-VEGF agents such as bevacizumab
- Anti-EGFR agents such as cetuximab (Correct answer)
- CDK 4/6 inhibitors such as palbociclib
- ALK inhibitors such as crizotinib
Correct answer: Anti-EGFR agents such as cetuximab
KRAS mutations activate downstream RAS/MAPK signaling that bypasses EGFR, rendering cetuximab and panitumumab ineffective in colorectal cancer.
Question 5: CDK 4/6 inhibitors such as palbociclib are approved in combination with endocrine therapy for which breast cancer subtype?
- Triple-negative breast cancer
- HER2-positive breast cancer
- Hormone receptor-positive/HER2-negative breast cancer (Correct answer)
- Inflammatory breast cancer
Correct answer: Hormone receptor-positive/HER2-negative breast cancer
CDK 4/6 inhibitors arrest cell cycle progression at the G1/S checkpoint and are approved for HR+/HER2- advanced breast cancer in combination with endocrine therapy.
Question 6: Which BRAF inhibitor is approved for BRAF V600E mutant unresectable melanoma?
- Gefitinib
- Erlotinib
- Vemurafenib (Correct answer)
- Crizotinib
Correct answer: Vemurafenib
Vemurafenib specifically targets the BRAF V600E mutation, inhibiting aberrant MAPK/ERK signaling and is FDA-approved for BRAF V600E-mutant melanoma.
Question 7: The mTOR inhibitor everolimus is FDA-approved in combination with exemestane for which indication?
- Advanced prostate cancer after enzalutamide failure
- Advanced HR+/HER2- breast cancer after non-steroidal aromatase inhibitor failure (Correct answer)
- Metastatic colorectal cancer as second-line therapy
- Renal cell carcinoma as first-line monotherapy only
Correct answer: Advanced HR+/HER2- breast cancer after non-steroidal aromatase inhibitor failure
Everolimus combined with exemestane is FDA-approved for postmenopausal women with advanced HR+/HER2- breast cancer after failure of a non-steroidal aromatase inhibitor.
OCC Targeted Therapy & Immunotherapy in Oncology 1
Which class of targeted therapy works by inhibiting the BCR-ABL tyrosine kinase, making it effective in chronic myeloid leukemia (CML)?