Optical imaging of kidney cancer with novel near infrared heptamethine carbocyanine fluorescent dyes

J Urol. 2013 Feb;189(2):702-710. doi: 10.1016/j.juro.2012.09.056. Epub 2012 Sep 20.

Abstract

Purpose: We assessed the application of near infrared heptamethine carbocyanine dyes, including IR-783 and the synthetic analogue MHI-148, as optical imaging agents for the rapid detection of human kidney cancer.

Materials and methods: The uptake, retention and subcellular localization of these organic dyes were investigated in cultured kidney cancer cells. Tumor specificity of dye uptake and retention was evaluated by whole body imaging of mice bearing human kidney cancer xenografts or freshly harvested clinical kidney cancer specimens. In addition, dye accumulation at the tissue and cellular levels was confirmed by ex vivo studies with results confirmed by fluorescence imaging of frozen tissue sections. Peripheral blood spiked with kidney cancer cells was stained to simulate the detection of circulating tumor cells.

Results: Preferential uptake and retention of carbocyanine near infrared dyes was observed in cultured human kidney cancer cells, human kidney cancer cell spiked whole blood, human kidney cancer xenografts and freshly harvested human kidney cancer tissues compared to normal kidney epithelial cells and normal host organs.

Conclusions: We describe a new class of near infrared heptamethine carbocyanine dyes that show potential for detecting kidney cancer cells in circulating blood and kidney cancer cells in clinical specimens. Near infrared carbocyanine dyes can be further developed as dual modality agents for deep tissue imaging of localized and disseminated kidney cancer in patients.

MeSH terms

  • Animals
  • Carbocyanines*
  • Diagnostic Imaging
  • Fluorescent Dyes*
  • Humans
  • Kidney Neoplasms / diagnosis*
  • Mice
  • Mice, Nude
  • Tumor Cells, Cultured

Substances

  • Carbocyanines
  • Fluorescent Dyes