Drugs for Lung Cancer Flashcards
(41 cards)
Name the drugs used in NSCLC
- Cisplatin
- Docetaxel
- Gemcitabine
- Paclitaxel
- Pemetrexed
- Vinorelbine
- Irinotecan
Name the drugs used in SCLC
- Doxorubicin
- Etoposide, VP-16
- Methotrexate
- Topotecan
- Cisplatin
- Carboplatin
- Ifosfamide
- Irinotecan
- Cyclophosphamide
- Vincristine
Name the drugs used in Adenocarcinoma
- Afatinib
- Bevacizumab (approved only for use in non-squamous NSCLCs)
- Crizotinib
- Erlotinib
Distinguish driver vs. passenger mutations?
Driver: mutations that are critical for cell growth or survival
- inactivation will result in cell death or differentiation into a normal phenotype
Passenger: mutations that are not critical for cell growth or survival
Discuss TK receptors activation in normal cells
- ligand binding to receptor results in dimerization and tyrosine residue trans-phosphorylation
- transduction to nucleus
- effects on nuclear transcriptoin can lead to cell growth, prolifeartion, and avoidance of apoptoic events
Discuss TK receptors activation in cancer cells
- RTKs activation via gene amplification, and nucleotide changes such as mutations lead to structural alterations in encoded proteins.
- Chromosome rearrangement leads to malignancy via the transcriptional activation of proto-oncogenes OR the creation of fusion genes
What are the mechanisms for TKI resistane?
- Mutation in ATP binding site for TKIs
- Polymorphisms in apoptosis gene (e.g. BIM)
- abscence of pro-apoptotic BH3 domain in 15% of East Asian population
- predictive of significantly shorter progression-free surival when compared to patients wtihotu BIM
What can lead to independent proliferative signals continuing, with or without TKI
KRAS or BRAF mutations
- KRAS mutations can render anti-EGFR drugs (Mabs or TKIs) ineffective becuase the proliferative pathway remains constitutively active DOWNSTREAM of the drug-induced blockade
- Most mutations occur at codons 12 and 13
- GENERALLY a negative response predictor to targeted therapy of **lung cancer and colorectal cancer **
- many downstream target proteins; some mutations in NSCLC correlate with inhibtion of cell cycel activation/progression
EML4-ALK Translocation
EML4 (echinoderm microtuble-associated protein-like 4) and ALK (anaplastic lymphoma kinase) fusion produces an oncogene that occurs in lung cancers that leads to activation of the MEK/ERK pathway and **cell proliferation. **
- family of abnormal (pro-malignant) fusion genes
- detectable in 2-7% of all NSCLC
- more prevalent in nonsmokers, in patients with a history of light smoking, and in patients with adenocarcinoma
VEGF
Proliferating solid tumors maintain blood supply by cells sensing oxygenation via hypoxia inducible factor (HIF-1) and the release of VEGF
Blocking formation of new blood vessels is an attractive target with some downsides
- reduce the distribution of concurrent chemo
- induce accumulation of more aggressive cells that have an increased capacity to spread to other organs
Describe inter-patient variation in drug PKs with orally administered targeted agents
Orally administered kinase inhibitors (e.g. EGFR and ALK TKIs) must be absorbed in stomach and SI before entering circulatory system. Metabolism of drugs may be influened by several host factors including bioavailability.
Do only smokers get lung cancer?
NO! Certain mutations are more common in smokers whereas others are more common in never-smokers
- EGFR mutations are more common in never-smokers
- KRAS mutations are more common in smokers
Discuss Genetic Testing
National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncology (ASCO) recommend routine testing for EGFR mutations and ALK rearrangements in all adenocarcioms.
- due to very low diagnostic yield of testing pure squamous cell tumors, this is not recommended
- DNA sequencing is method used in most EGFR studies
- FISH is a preferrsed choice for ALK gene rearrangement testing
Describe the general treatment plan for SCLC and NSCLC
- SCLC: metastasis occurs early so chemotherapy/radiation is the only option
- NSCLC: surgical resection if there has been no metastasis (early stage disease)
- Metastasize very early, spreading most commonly to the adrenals, liver, brain and bone
What is the most common reigmen for SCLC?
Etoposide + Cisplatin or Carboplatin
What is the coventional treatmetn of NSCLC?
Revolves around CISPLATIN and one of a number of drugs, commonly a taxane, and maintenace treatment often involves a DHFR inhibitor that is a MTX analog (Pemtrexed)
- **CISPLATIN AND paclitaxel, gemcitabine, docetaxel, vinorelbine, irinotecan or pemetrexed **
- Based upon appropriate genetic markers, TKIs and VEGF inhibitors may also be appropriate.
- Bevacizumab can be used for patients with non-squamous histology, no brain mets, or no hemoptysis.
Carboplatin
MOA: forms DNA intrastrand crosslinks and adducts
Adverse Effects
- Allergic (platinum) reactions.
- Dose related myelosuppresion
- Cumulative anemia
- Dose related N/V
- Blood chemisry dyscrias, increased hepatic enzymes, BUN & Cr
Cisplatin
MOA: platinum complexes bind and crosslink DNA → apoptosis
Adverse Effects
- Allergic (platinum) rxns
- Dose-related severe nephrotoxicity, mylosuppresion, and n/v
- Significant ototoxicity (tinnitus and occasionaly deafness) reported in children
Cyclophosphamide
MOA: covalently cross-links DNA strands at guanine N-7 → cell death; pro-drug that is activated in liver.
Adverse Effects
- Blood dyscrias –> anemia/infection
- Renal compromise, hemorrhagic cystitis (mesna is protective), n/v, rashes
- Amenorrhea/infertility
- Monitor for secondary malignancies
- Pulmonary fibrosis
Docetaxel
MOA: bind to B-tubulin and enhance assembly of tubulin dimers into microtubule polymers, which stabilizes existing microtubules and inhibits disassembly. The inability to depolymerize results in mitotic arrest.
Adverse Effects
- increased mortality in NSCLC
- edema (give steroids)
- contraindicated with increased bilirubin/ALK phos/SGOT/SGPT
- dose-limiting neutropenia
- sensory neuropathy
Doxorubicin
MOA: intercalation between DNA base pairs leads to ↓ DNA/RNA synthesis. Also inhibits DNAtopoisomerase II. Also chelates iron, producing free radicals that cleave DNA.
Adverse Effects:
- mylosuppression
- CHF
- hepatic disease
- secondary malignancies
- extravasational necrosis
- n/v
Etoposide, VP-16
MOA: inhibition of topoisomerase II → induces DNA breakage. Causes cell death during the late S phase and G2 phase. Activated by dephosphorylation
Adverse Effects
- Myelosuppresion, infection
- Dose-limiting hematologic toxicity
- N/V
- diarrhea
- Alopecia
Gemcitabine
MOA: DNA polymerase inhibitor via incorporation of triphosphate form during DNA synthesis.
Adverse Effects: myelosuppresion, infection, arthralgia, drwosiness, fatigue, N/V, alopecia, sensory peripheral neuropathy (<10%)