A novel optical biosensor format for the detection of clinically relevant TP53 mutations

Area of Science:

• Biotechnology
• Molecular Biology
• Genetics

Background:

• TP53 gene mutations are prevalent in most cancers, impacting patient prognosis and therapy response.
• Detecting specific TP53 mutations, particularly in zinc-binding domains, is critical for predicting radiotherapy and chemotherapy resistance.
• Existing detection methods often yield contradictory results.

Purpose of the Study:

• To develop a DNA biosensor for detecting clinically relevant TP53 gene mutations.
• To evaluate the sensitivity and potential improvements of the biosensor system.
• To explore the use of Escherichia coli mismatch repair proteins to enhance detection sensitivity.

Main Methods:

• Utilized a TI-SPR-1 surface plasmon resonance system with Spreeta chips.
• Developed a DNA biosensor using thiolated probes complementary to TP53 zinc-binding domains.
• Tested detection of mutations in oligonucleotides and PCR products.
• Investigated the use of MutS and single strand binding protein (SSB) for signal enhancement.

Main Results:

• The DNA biosensor successfully detected TP53 mutations in both oligonucleotides and PCR products.
• A small difference in hybridization signal was observed initially.
• MutS protein did not bind to mismatch oligonucleotides.
• Single strand binding protein (SSB) increased biosensor sensitivity threefold by binding unhybridized probes.

Conclusions:

• The TI-SPR-1 system is a viable tool for detecting clinically relevant TP53 gene mutations.
• Single strand binding protein significantly enhances biosensor sensitivity.
• This biosensor offers advantages over current technologies, including lower cost, simplicity, and speed.