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Q1) Which of the following components of radiotherapy are used for Superficial radiation.
a) Electron b) Neutron
c) UV rays d) Gamma rays
Ans 1 a ) Electrons
Radiation is delivered as electrons, photons and neutrons
Electrons have the lowest penetration (6cm) from the surface of skin. They partially penetrate the body
All others are used for more deeper penetrations
Q2) Obesity is associated with highest risk of developing which malignancy? A. Renal cell carcinoma B. CA Endometrium C. Gastric cancer
d) Esophagus cancer
Ans 2 ) b Endometrial
Endometrial cancer: Obese and overweight women are two to about four times as likely as normal-weight women to develop endometrial cancer (cancer of the lining of the uterus), and extremely obese women are about seven times as likely
Esophageal adenocarcinoma: People who are overweight or obese are about twice as likely as normal-weight people to develop a type of esophageal cancer called esophageal adenocarcinoma, and people who are extremely obese are more than four times as likely
a) Fermentation of glucose to lactate observed even in the presence of completely functioning mitochondria is known as the Warburg Effect.
b) Warburg Effect is thought to be an early event in oncogenesis due to oncogene mutation
c) Aerobic glycolysis is a symbiotic process supplying lactate to the nearby tumor cells which use in citric acid cycle
d) Rate of glucose metabolism through aerobic glycolysis is higher and more efficient
Ans d
Cancer cells can alter their metabolism even when oxygen is abundant; they break down glucose but
do not, as normal cells would do, send the resulting pyruvate to the mitochondria for conversion, in an oxygen-dependent process, to carbon dioxide.
This is the phenomenon of aerobic glycolysis, or the Warburg effect, and leads to the production
of lactate.
Aerobic glycolysis (fermentation as in Warburg effect) is faster but not more efficient than the mitochondrial process.
Q 4) False about chemokines
a) CXCL12, on breast cancer cells is also present in bone marrow, lymph nodes, liver and lung
b) Melanoma cells increased receptors CXCR4, CCR7, and CCR10 also expressed on Lymph nodes, lung, liver, bone marrow
c) Chemokines and their receptors play an essential role in the successful outgrowth of tumors
d) The normal counterparts of cancer cells also express chemokines and their ligands equally
Ans 4) d
CXCL12, which is the ligand for the chemokine receptor CXCR4, enriched on breast cancer cells also present in bone marrow, lymph nodes, liver and lung
Melanoma cells were found to express elevated levels of the receptors CXCR4, CCR7, and CCR10 also expressed on Lymph nodes, lung, liver, bone marrow
Chemokines and their receptors play an essential role in the successful outgrowth of tumors at preferential sites supporting seed soil hypothesis
Chemokines and their receptors are expressed more by cancer cells than their normal counterparts
Ref sabiston
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