Caspase-8 cleaves and activates several effector caspases, caspase-3, 6, 7 to complete apoptotic cell death.

TLS Online TPP Program

#Id: 10466

#Unit 4. Cell Communication and Cell Signaling

Children with hereditary (familial) retinoblastoma inherit one defective copy of the RB gene 

(sometimes seen as a small deletion on one of the two copies of chromosome 13)

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#Id: 10467

#Unit 4. Cell Communication and Cell Signaling

Sporadic retinoblastoma, inherit two normal RB alleles, each of which has undergone a LOF somatic mutation in a single retinal cell

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#Id: 10468

#Unit 4. Cell Communication and Cell Signaling

Subsequent loss or inactivation of the remaining normal allele in a somatic cell, known as loss of heterozygosity causes cancer to develop.

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#Id: 10469

#Unit 4. Cell Communication and Cell Signaling

Three mechanisms for LOH of tumor-suppressor genes:

Inactivating mutation or deletion

Chromosome missegregation

Mitotic recombination

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#Id: 10470

#Unit 4. Cell Communication and Cell Signaling

TLS Online TPP Program

#Id: 10471

#Unit 4. Cell Communication and Cell Signaling

A mutation, valine to glutamine in the TM region of the HER2 receptor causes dimerization of the receptor, even in the absence of the ligand, transforming it into the oncoprotein NEU, a constitutively active protein tyrosine kinase.