Heme Lymph Flashcards
(150 cards)
Oncogenes
Ras
Tumor suppressor
P53
Go G1 S and g2 M
M mitosis
Go resting phase of G1
G1has restriction point whihc activation of oncogenes overrides
S synthesis dna replication phase
G2 has dna replication checkpoint which tumor suppressor genes p53 override
Primary chemo
Chemo is the primary treatment in advanced cancer with no alternative treatment
Relieve tumor related symptoms, improve quality of life, prolong time to tumor progression
Curable cancer with primary chemo
Hodgkin and non Hodgkin lymphoma, choriocarcinoma, germ cell cancer, and acute myelogenous leukemia
Kids-burkitts, wilms, embryonal rhabdomyosarcoma, ALL
Neoadjuvant chemotherapy
For localized cancer in adjunct ro other methods whihc are less than completely effective
Reduce size of primary tumor to make surgery easier or spare vital organs
Chemo given for time after surgery as ADJUVAnT therapy
ADJUVAnT chemotherapy
After surgery
Reduce incidence of local adhd systemic recurrence and improve overall survival of patients
Prolong disease free survival and overal survival
What is the log kill hypothesis
Symptoms high number of cancer cells/death -Infrequent treatment, treatment started too late , prolongation of survival with eventual death
Diagnosis pretty high cancer cells- Combination chemotherapy, intensive treatment schedule, therapy continued after clinical evidence of cancer disappears, cure
Surgery lower number-Early surgery combines with intensive adjuvant therapy
Primary/inherent chemotherapeutic resistance
Drug resistance int he absence of prior exposure to available standard agents
Genomic instability of cancer p53
Acquired chemo drug resistance
Develops in response to exposure to a given cancer drug
Genetic change-amplification or suppression fo a particular gene
Increasing heterogeneity over time ->tumor continues to proliferate and is no resistant to treatment x
P-glycoproteins, PGP
On tissues with barrier functions including the kidney, liver and GI tract
Pharmacological barrier sites including the blood brain barrier and the placental blood barrier
High baseline expression of PGP correlates wit hprimary/inherent resistance to natural products
Can be overprexpressed leading to acquired drug resistance
Therapeutic index
TD50/ED50
Chemo therapeutic index
Close ED50 and TD50 when desired is low ED50 and high TD50
High doses are required ot maximize rapid cancer cell death
AE chemo
Non cancerous proliferating cells —bone marrow precursors of blood cells(cytopenias, myelosuppression) —intestinal epithelial cells —oral mucosa —gonadal cells —hair follicles-alopecia
MOA alkylation agents
Transfer of alkyl groups to DNA leading to DNA cross linking
Arrest in late G1, early S phase
Individual drugs vary in how they do this-cisplastin versus cyclophosphamide
What cells are most susceptible to alkalyating agents
Replicating cells
Resistance alkalyating agents
Increased capability to repair DNA lesions through increased expression of activity of DNA repair enzymes
Decreased cellular transport of alkyating drug
Increased expression or activity of glutathione and glutathione associated proteins
—these are needed to conjugate the alkyating agents
Alkylation agents adverse effects
Primarily occur in rapidly growing tissue -bone marrow —myelosuppression -GI tract —diarrhea -reproductive system
N/V
Blistering at the site of administration
Carcinogenic-increased risk of secondary malignancies AML
MOA antimetabolites
Methotrexate-folic acid metabolite
5-FU uracil analog
Cytosine arabinoside-cytosine deoxyriboside
Mimic and/or reduce the essential components needed for the formation of DNA, RNA and proteins
Arrest and/or DNA damage often occurs during S phase
Cells most susceptible to antimetabolites
Replicating
Resistance antimetabolites
Inhibition of metabolism intoactive metabolites-cytarabine and the active metabolite of art-ctp
Decrease drug transport
-methotrexate and the reduced folate carrier or folate receptor
Decreased formation of poly glutamate metabolites by folyl polyglutamate synthase (FPGS)
-important for methotrexate, pemetrexed and pralatrexate
Ae antimetabolites
Myelosuppression
N/v
GI toxicity(5-FU)
Hand foot syndrome
- painful erythema and swelling of the hands and feet
- pemetrxed
Natural products MOA
Tubules polymerization disrupted by vinblastine, vincristine, vinorelbine and enhanced by paclitaxel, docetaxel, and cabazitaxel
Topoisomerase inhibitors
Topoisomerase 1 topotecan, irinotecan
Topoisomerase 2-etoposide
Mechanism of resistance natural products
P-glycoproteins mediated drug efflux
Point mutations ind rug binding (topo 1 and 2)