Application of combined RNA in situ hybridization and multiplex immunohistochemistry to unravel tumor heterogeneity in prostate cancer
Nallasivam Palanisamy, PhD
Associate Scientist, Henry Ford Health System
Prostate cancer is a complex disease with multiple tumors originating independently at different stages of growth. Despite the identification of key morphological differences between individual tumor foci, the underlying molecular mechanisms driving growth within individual foci are often poorly understood. This is because traditional molecular and genetic studies involving systemic sampling of large tumor foci or high Gleason grade tumor foci often miss small tumor foci with important driver aberrations and high metastatic potential. To avoid overlooking foci with important driver aberrations, well-characterized cancer-specific markers can be used to screen the entire prostate tissue to assess molecular differences in individual tumor foci. A clearer understanding of foci-specific molecular heterogeneity is important, as these molecular differences may prognosticate tumor growth and treatment success.
In this presentation, we will demonstrate the power of dual immunohistochemistry (IHC) and in situ hybridization (ISH) as a technique to probe multiple cancer-specific molecular markers in the morphological context. Combining the protein detection capabilities of IHC with single-molecule mRNA expression analysis using RNAScope® ISH technology builds a more complete and robust picture of the molecular mechanisms governing individual tumor foci. In addition to highlighting the development of dual IHC/ISH to characterize solid tumor heterogeneity at the molecular level, we will present how high-sensitivity, single RNA molecule detection ISH combined with IHC can be applied to other biological questions to provide valuable information on the expression of molecular markers in nearly any biological pathway.
- Applying dual IHC/ISH methods
- Understanding tumor heterogeneity