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TLS Online TPP Program

#Question id: 15303

Neurofibromatosis, a benign tumor of the sheath cells that surround nerves, is caused by
a.  Loss of both alleles of NF1
b.  Mutation in RAS GAP-type protein
c.  A single mutant NF1 allele
d.  Mutation in SRC protein

#Unit 4. Cell Communication and Cell Signaling
  1. a,  b and c
  2. b, c and d
  3. b and d
  4. a and b
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TLS Online TPP Program

#Question id: 15307

#Unit 4. Cell Communication and Cell Signaling

In attached table some Tumor‐Suppressor Genes are given with their inherited syndrome; select correctly matched genes with their causing syndrome

GeneInherited syndrome
i. TP53Li-Fraumeni syndrome
ii. INK4aFamilial melanoma
iii. PTENFamilial gastric cancer
iv. E-CadherinCowden disease
v. VHLvon Hippel-Lindau syndrome
TLS Online TPP Program

#Question id: 15306

#Unit 4. Cell Communication and Cell Signaling

The transformation of a normal cell to a cancer cell is accompanied  by the loss of function of one or more tumor‐suppressor genes. High‐throughput sequencing studies have identified hundreds of genes that are implicated as tumor suppressors in humans. Some of the better characterized genes;

GenePrimary tumorProposed function
i) APCColorectalBinds β-catenin acting as transcription factor
ii) BRCA1BreastDNA repair
iii) MSH2, MLH1Melanoma, pancreatic

p16: Cdk inhibitor


ARF: stabilizes p53

iv) E-CadherinBreast, colonCell adhesion molecule
v) INK4aColorectalMismatch repair
vi) NF1NeurofibromasActivates GTPase of Ras

Choose incorrect matching regarding tumor‐suppressor genes/primary tumor/proposed functions;
TLS Online TPP Program

#Question id: 15305

#Unit 4. Cell Communication and Cell Signaling

The multi-hit model, which proposes that multiple mutations are needed to cause cancer, which of the following is incorrect regarding to this model?
TLS Online TPP Program

#Question id: 15304

#Unit 4. Cell Communication and Cell Signaling

An activating mutation of one of the two alleles of a proto-oncogene converts it into an oncogene, This can occur by EXCEPT
TLS Online TPP Program

#Question id: 1538

#Unit 4. Cell Communication and Cell Signaling

Many aspects of the biology of stem cells, including maintenance of pluripotency, self-renewal, and differentiation, are controlled by the phenomenon of RNA interference involving a variety of small molecules of RNA.

Match the following miRNA (Column I) with their target gene (Column II).

Column I

Column II

a. Let-7 miRNA

i. Bcl-2

b. miR-16

ii. PTEN phosphatase

c. miR-125a and miR-125b

iii. Myc

d. miR-21

iv. LIN28

TLS Online TPP Program

#Question id: 1537

#Unit 4. Cell Communication and Cell Signaling

Transformation of mature cells may also occur due to aberrant expression of stemness genes, resulting in cell clones with a dedifferentiated phenotype and self-renewing capacity resembling stem cells. Recent experimental evidence supporting this proposal has been provided with the induction of adult somatic cells into pluripotent stem (iPS) cells through ectopic expression of four genes encoding the pluripotency factors Oct4 and Sox2, the transcription factor Klf4, and the oncoprotein c-Myc in mouse or human fibroblasts. However, along with pluripotency comes the capability of generating teratomas. On the basis of the above information which of the following outcome is most appropriate?