What is specific to DNA repair gene oncogenesis mechanism?
needs silencing of both alleles to trigger oncogonesis
What are the 3 DNA repair systems?
- mismatch repair
- nucleotide repair
- homologue recombination repair
Which oncogenes are involved in mismatch repair? (3)
- MSH2
- MLH1
- MSH6
Which oncogenes are involved in nucleotide excision repair? (3)
- XPA
- XPC
- XPG
What does the mismatch repair intervene on?
non matching nucleotide in DNA
What are the dimer complexes formed in MMR mechanism?
- MUTSa : MSH2 + MSH6
- MUTSb : MSH2+ MSH3
What is the role of MUTSa?
it is responsible for recognizing the mismatch within the DNA duplex
What is the role of the MUTSb dimer?
Specifically repairs IDL mispairs (insertion deletion loops)
Which complex is recruited by MUTS?
- MLH1/PMS2
- MLH1/MLH3
What type of damage does NER remove?
damage caused by UV radiation
What is the role of the XPC protein?
recognizes the bulky DNA (like pyrimidine dimers)
What complex is recruited by XPC?
XPA/XPG/RPA/TFIIH complex
What is the role of TIIF in NER mechanism?
unwinds the DNA
What is the role of XPG?
Helps cut the DNA strand
What is the role of XPA in NER mechanism?
Assembly of NER complex and damage verification
Which protein rebuilds the DNA in NER?
Polymerase delta / epsilon
Which neoplasms are caused by mismatch repair silencing? (4)
- colorectal carcinoma
- ovarium carcinoma
- endometrium carcinoma
- stomach carcinoma
Which neoplasms are caused by NER silencing? (3)
- basocellular carcinoma
- planocellular carcinoma
- melanoma
