MHI-148 ((2-[2-[2-Chloro-3-[2-[1,3-dihydro-3,3-dimethyl-1-(5-carboxypentyl)-2H-indol-2-ylidene]-ethylidene]-1-cyclohexen-1-yl]-ethenyl]-3,3-dimethyl-1-(5-carboxypentyl)-3H-indolium bromide)) is a near-infrared heptamethine cyanine dye with tumour-targeting properties for cancer detection, diagnosis and research. MHI-148 is immediately taken up and accumulated by the lysosomes and mitochondria of tumour cells but not in the lysosomes and mitochondria of normal cells.
The heptamethine cyanine dye MHI-148 is an analogue of IR-783, which was initially synthesized as an optical imaging agent to detect human kidney cancer. MHI-148 dye-conjugated porous Gd silicate nanoparticles were developed as a NIRF-MRI dual-modal contrast agent for LLC/LL2 tumours. In another work, an MHI-148-based PET imaging probe labelled with Cu64 was developed as a tumour-targeting agent. These studies showed that the MHI-148 dye has active tumour-targeting properties and enhanced accumulation in tumours compared to control groups. NIRF dye MHI-148 can be used for effective imaging with good stability and specificity in different types of tumour cell lines and tumour xenografts, such as kidney cancer, prostate cancer and lung cancer. Thomas et al. have also used MHI-148 as a tumour-targeting agent conjugated to nanoparticles for breast cancer treatment[1].
[1] Jian Song. “Near-infrared fluorescence imaging of hepatocellular carcinoma cells regulated by β-catenin signaling pathway.” Frontiers in Oncology 13 (2023): 1140256.