Cancer

Question 1

Benign tumor

Answer 1

A non-invasive tumor that does not spread to other tissues.

Question 2

Pre-malignant tumor

Answer 2

A tumor with potential to become cancerous if further mutations occur.

Question 3

Malignant tumor (cancer)

Answer 3

A tumor that invades and spreads to distant tissues (metastasis).

Question 4

Carcinoma

Answer 4

Cancer from epithelial cells (85% of all cancers).

Question 5

Sarcoma

Answer 5

Cancer of mesoderm-derived tissues like bone and muscle

Question 6

Adenocarcinoma

Answer 6

A carcinoma originating from glandular tissue.

Question 7

Leukemia

Answer 7

Cancer of blood-forming tissues, leading to abnormal white blood cells.

Question 8

Lymphoma

Answer 8

Cancer of lymphatic tissue.

Question 9

Proto-oncogene

Answer 9

Normal gene regulating growth; can become an oncogene if mutated.

Question 10

Oncogene

Answer 10

A mutated proto-oncogene that promotes uncontrolled cell division.

Question 11

Tumor suppressor gene

Answer 11

Gene that inhibits cell growth; both copies must be lost for cancer to develop.

Question 12

Two-hit hypothesis

Answer 12

Both alleles of a tumor suppressor gene must be inactivated for cancer to form.

Question 13

Multiple-hit hypothesis

Answer 13

Several sequential/successive mutations are needed for cancer development.

Question 14

Human papilloma virus (HPV):

Answer 14

Virus that causes cervical cancer by inactivating p53 and Rb with E6 and E7 proteins, respectively

Question 15

Sporadic tumor

Answer 15

Tumor caused by mutations acquired during life, not inherited.

Question 16

Neurofibromatosis

Answer 16

Inherited condition due to NF1 gene mutation, leading to tumors in nerves.

Question 17

Adenomatosis polyposis coli (APC)

Answer 17

Mutation in the APC gene causes colon polyps and cancer.

Question 18

Retinoblastoma

Answer 18

Cancer of the retina due to RB1 gene mutation; can be hereditary or sporadic.

Question 19

p53 and cancer

Answer 19

Tumor suppressor gene controlling cell cycle and apoptosis; often mutated in cancers.

Question 20

BRCA

Answer 20

Tumor suppressor genes involved in DNA repair; mutations raise risk of breast and ovarian cancer.

Question 21

Xeroderma pigmentosum

Answer 21

Disorder with defective DNA repair, leading to extreme UV sensitivity and skin cancers.

Question 22

miRNAs and cancer

Answer 22

Small RNAs that regulate gene expression; deregulation contributes to cancer.

Question 23

Metastasis

Answer 23

Spread of cancer cells from primary tumor to other body parts via blood or lymph.

Question 24

‘Seed and soil’ theory

Answer 24

Metastasis depends on compatibility between tumor cells and target tissue microenvironment.

Question 25

Founder effect

Answer 25

High frequency of a specific mutation in a population due to inheritance from a small ancestral group.

Question 26

EGF – epidermal growth factor receptor

Answer 26

A receptor that stimulates cell growth; often *overexpressed* in cancer.

Question 27

Fibroblast growth factors (FGFs)

Answer 27

Promote cell growth and tissue repair; overexpression leads to tumors.

Question 28

Platelet-derived growth factor (PDGF)

Answer 28

Stimulates cell growth during wound healing; can be hijacked by cancer cells.

Question 29

Growth factor receptors (GFRs)

Answer 29

Cell surface receptors that trigger growth signaling; mutations cause unregulated growth.

Question 30

Ras oncogene:

Answer 30

Frequently mutated gene that leads to continuous cell growth; found in colon, lung, and pancreatic cancers.