Tumor Immunology Flashcards
Cell transformation
Changes in physiology, morphology, protein expression, and growth characteristics that take place as a normal cell become malignant
Carcinogenesis
Tumor formation
What is the difference between malignant and metastatic tumors?
- Malignant grows & invades other tissues
- Metastatic disseminates to distant organs → blood → creates new tumors there
What is the difference between a carcinoma and a sarcoma
- Carcinomas effect that the little cells
- Sarcomas effect organs of mesenchymal cell origin (i.e. bone, lymph, CT, circulatory)
Which cells are affected by Leukemia, Lymphoma and Myeloma?
- Leukemia: circulating immune cells (B, T, Myeloid)
- Lymphoma: lymphoid cells
- Myeloma: plasma B-cells
What is the difference between de-differentiation & re-differentitaion
- De-differentiation: cells lose their differentiation as they become malignant
- Re-differentiation: they lose their ability to respond to signals as they reach their terminal end
Somatic cell mutation Theory
Somatic mutation to cells → development of oncogenes and results in protective effects to the cancer cell
What is an example of a somatic cell mutation Theory?
Philadelphia chromosome; t(9;22) → ABL/BCR oncogene: activates bcr apoptotic protective protein
Cancer stem cell hypothesis
Polyclonal evolution of cells from within a primary tumor; one of which may have capabilities of a stem cell
(self-renewal, proliferation, tumorigenicity, resistance to chemotherapy)
Cancer stem cell hypothesis means what in terms of treatment?
must target the stem cell-like cells to stop it
(even w/chemo the CSCs are still present and malignancy can reappear after some time)
What characteristics enhance cancer growth?
- signal their own growth
- ignore apoptosis signal/immune system evasion
- angiogenesis
- metastasis
Oncogenes are the mutant of ______.
proto-oncogenes: stimulate growth & regulate apoptosis
Overall, the development of tumors is a multistep process of ______ → expression of phenotype.
clonal evolution (somatic mutation)
What families to the following oncogenic viruses belong to:
- Epstein-Barr
- Human T Lymphocyte Virus
- Kaposi Sarcoma
- EBV: herpesviridae
- HTLV-1: retroviridae
- KSHV/HHV-8: herpesviridae
What type of cancer is caused by EBV (4)?
- Burkitt’s lymphoma
- Hodgkin’s lymphoma
- Post transplantation lymphoma
- Nasopharyngeal carcinoma
What type of cancer is caused by HTLV-1?
Adult T-cell leukemia
What type of cancer is caused by KSHV/HHV-8 (3)?
- Kaposi’s sarcoma
- Pleural effusion lymphoma
- Multicentric Castleman’s disease
Oncogenes of EBV & HTLV-1?
- EBV: LMP-1
- HTLV-1: Tax
Oncogenes of KSHV/HHV-8 (8)
- Kaposin B
- LANA
- vCyclin
- vFlip
- vBcl2
- vMIPs
- vGCPR
- vIL-6
(Mn: Kaposin B. LANA is a pro Cycler who Flipped her bike over a Buckle left in the road. Her MIPs helmet saved her brain, but they had to do CPR for 6 minutes)
LMP-1 function
(EBV oncogene)
- molecular signaling dysregulation NF-kB activation
- lymphoproliferation
Tax function
(HTLV-1 oncogene)
- Molecular signaling dysregulation NF-kB activation
- Immortalization
(first one is the same as EBV)
Oncogene function of KSHV (5)
(Kaposi B, LANA, vFlip, vCyclin, vBcl2, vMIP, vGCPR, vIL-6)
- multiple-signaling events
- cell cycle dysregulation
- Inhibition of apoptosis
- Immune evasion
- Autocrine & paracrine functions
EBV will infection which cell types?
- Epithelial cells
- B cells
(there will be pools of uninfected & infected cells; some may become latent → lytic replication when favorable)
How do the EBV proteins (EBNAs) lead to immortalization (lymphoma development)?
- EBNA-1: genome replication; p53 degradation
- EBNA-2: upregulates viral (LMP1) & cellular (c-myc) oncogenes
- EBNA-3A: reg. notch signaling
- EBNA-3B: overcomes cell cycle inhibition
- LMP-1: mimics CD40L binding signal → blocks apoptosis & upregulates cell signaling
The effect of retrovirus depends on _____
where it integrates into the infected cell (if it is near tumor suppressor genes → tumorigenesis)
Hodgkin’s vs. Non-Hodgkin’s lymphoma
Hodgkins: Reed-sternberg cells
Non-Hodgkins: large B cell lymphoma, follicular lymphoma, many B & T cells form non-hodgkins