MCBoM- Tumours Flashcards Preview

1st year Medicine > MCBoM- Tumours > Flashcards

Flashcards in MCBoM- Tumours Deck (41):
1

Malignant, bone

Osteosarcoma

2

Benign, cartilage

Chondroma

3

Malignant, cartilage

Chondrosarcoma

4

Benign, fat

Lipoma

5

Malignant, fat

Liposarcoma

6

Benign, smooth muscle

Leiomyoma

7

Malignant, smooth muscle

Leiomyosarcoma

8

Benign, skeletal muscle

Rhabdomyoma

9

Malignant, skeletal muscle

Rhabdomyosarcoma

10

Benign, blood vessels

Hemangioma

11

Malignant, blood vessels

Angiosarcoma

12

Benign, melanocytic (skin pigment)

Naevus

13

Malignant, melanocytic

Melanoma

14

Benign, meningeal

Meningeioma

15

Benign, nerve sheath

Neurofibroma

16

Malignant, nerve sheath

Malignant peripheral nerve sheath tumour

17

Benign, mixed structures

Mature teratoma

18

Malignant, mixed structures

Immature teratoma

19

Benign, bone

Osteoma

20

Hamartoma

Developmental malformation, mass of disorganised but mature specialised tissue indigenous to site, eg birthmark

21

Dysplasia

Disordered growth
Variable cell shape and size
Deeply stained nuclei
Increased number of cell divisions
High nuclear:cytoplasm ratio

22

Grading

Degree of differentiation
1-3-anaplastix

23

Staging

Extent of disease spread
TNM or I - IV

24

Apoptosis mechanism

Mitochondria release cytochrome c to cytoplasm
Binds to APAF 1 (apoptosis protease factor) to form wheel of death
Activates to form apoptosome

25

Proto oncogenes examples

C ras, c myc, N myc, EGF
Promote proliferation

26

Tumour suppressor genes examples

Rb, p53, APC (adenomatous polyposis coli), TGF beta
Arrest growth at G1/S checkpoint

27

Primary abnormalities

Gatekeepers
Genes whose mutation or altered expression relieves normal controls and promotes outgrowth of cancer cells

28

Secondary abnormalities

Caretakers
Genes whose disruption caused genome instability, increasing the frequency of alteration in gatekeeper genes

29

Gain of function mutation

Dominant effect, one defective allele needed
Proto oncogene to oncogene

30

Loss of function mutation

Both alleles need to be inactivated to give phenotypic change
Tumour suppressor gene to non functioning

31

Growth factors

Epidermal and platelet derived GFs-> stimulates growth and leads to cascade for cyclin D and proliferation

Transforming growth factor beta-> inhibitory, switches on CDK inhibitor protein so stops proliferation

32

Colorectal tumour initiation

Mutation stops destruction complex from forming, so beta catenin is deregulated
Beta catenin can then switch on genes that drive cell survival and proliferation

33

E-cadherin

Cell surface transmembrane proteins expressed by cells
Mediates cell-cell adhesion
Acts as receptor and ligand, bind to each other and to catenins in cell which are bound to cytoskeleton
Ca dependent
Tumour suppressor, down regulated in tumour invasion

34

Integrins

Cell surface transmembrane proteins
Alpha and beta units
Mediate cell-ECM adhesion
Provides polarity for survival and migration

35

Lymphatic spread

Mainly carcinomas (epithelial)

36

Haematogenous spread

Mainly sarcomas (mesenchymal) through blood vessels

37

Transcoelomic spread

Through body cavities
Mainly carcinoma

38

HPV

DNA oncogenic virus
Viral DNA integrated to host genome
Clonal integration, same site on same chromosome
Leads to overexpression of E6 and E7 proteins, prevents inhibition of CDK4 and facilitates degradation of p53 gene product

39

Epstein-barr

DNA oncogenic virus

BURKITTS LYMPHOMA
B cell neoplasm
Should be controlled by immune system, but in Africa chronic malaria favours spread, endemic
Overexpression of c-myc oncogene

B CELL LYMPHOMA
In immunosuppressed individuals
Tumours in lymphoid tissue or CNS

HODGKINS DISEASE
Distinctive neoplastic giant cells
Express LMP1 which has transforming activity

NASOPHARYNGEAL CARCINOMA
Affects epithelial cells of oropharynx and B lymphocytes
Episome genome, doesn't integrate

40

Hepatitis B

DNA oncogenic virus
Chronic persistent infection
HBx protein binds to p53, disrupts growth control of liver cells leading to cirrhosis

41

Human T cell leukaemia

RNA oncogenic retrovirus
Infection by transmission of infected T cells by fluid exchange