Comparative Study of Tumor Targeting and Biodistribution of pH (Low) Insertion Peptides (pHLIP® Peptides) Conjugated with Different Fluorescent Dyes
Acidification of extracellular space promotes tumor development, progression, and invasiveness. pH (low) insertion peptides (pHLIP® peptides) belong to the class of pH-sensitive membrane peptides, which target acidic tumors and deliver imaging and/or therapeutic agents to cancer cells within tumors.
Ex vivo fluorescent imaging of tissue and organs collected at various time points after administration of different pHLIP® variants conjugated with fluorescent dyes of various polarity was performed. Methods of multivariate statistical analyses were employed to establish classification between fluorescently labeled pHLIP® variants in multidimensional space of spectral parameters.
The fluorescently labeled pHLIP® variants were classified based on their biodistribution profile and ability of targeting of primary tumors. Also, submillimeter-sized metastatic lesions in lungs were identified by ex vivo imaging after intravenous administration of fluorescent pHLIP® peptide.
Different cargo molecules conjugated with pHLIP® peptides can alter biodistribution and tumor targeting. The obtained knowledge is essential for the design of novel pHLIP®-based diagnostic and therapeutic agents targeting primary tumors and metastatic lesions.
Key wordsImaging Tumor acidity Fluorescent-guided surgery Targeting of submillimeter metastatic lesions
- 27.Fox J, Weisberg S (2011) An R companion to applied regression. Sage, Thousand OaksGoogle Scholar
- 33.Pulaski BA, Ostrand-Rosenberg S (2001) Mouse 4T1 breast tumor model. Curr Protoc Immunol Chapter 20:Unit 20 22.Google Scholar