Dual-color-coded imaging of viable circulating prostate carcinoma cells reveals genetic exchange between tumor cells in vivo, contributing to highly metastatic phenotypes.

Color-coded imaging analysis revealed yellow fluorescent metastasis precursor cells that were readily recognized in the blood of tumor-bearing mice after mixtures of red fluorescent protein (RFP)- and green fluorescent protein (GFP)-expressing PC-3 human prostate carcinoma cells were implanted in the nude mouse prostate and metastasized. The yellow fluorescent cells were purified from the blood of nude mice to 99% homogeneity by FACS, expanded in culture, and reimplanted in the prostate of nude mice. The yellow fluorescent phenotype was heritable and stably maintained by tumor cells for many generations in vitro and in vivo.

Increased expression of apoptosis inhibitor protein XIAP contributes to anoikis resistance of circulating human prostate cancer metastasis precursor cells.

Survival in lymph or blood is an essential prerequisite for metastasis of carcinoma cells to distant organs. Recently, we reported isolation and initial biological characterization of circulating metastatic cells in a fluorescent, orthotopic, metastatic nude-mouse model of human prostate cancer. Here we show that the metastatic human prostate carcinoma cells selected for survival in the circulation have increased resistance to anoikis, which is apoptosis induced by cell detachment.

Role of colony stimulating factor-1 in brain damage caused by ischemia.

A marked effect of colony stimulating factor-1(CSF-1) on microglial response and neuron survival in cerebral cortex ischemic damage was observed. In osteopetrotic op/op mice, which lack systemically functional CSF-1 microglia do not respond to ischemic damage to the cerebral cortex, and the infarcts are considerably larger than in CSF-1 producing mice with similar vascular impairment. Delivery of extraneous CSF-1 to op/op mice alleviates the functional deficiency of the microglia and potentiates neuron survival in ischemic lesion.

Colony stimulating factor-1 potentiates neuronal survival in cerebral cortex ischemic lesion.

The effect of the cytokine, colony stimulating factor-1 (CSF-1), on neuronal survival in cerebral cortex ischemic lesion was determined. Ischemic lesions were made in C3H/HeJ mice by disrupting blood vessels that penetrate the cerebral cortex from the pial-vascular plexus. Recombinant human colony stimulating factor 1 (rhCSF-1) was delivered in chitosan microcapsules that were either implanted intraperitoneally 2 weeks before surgery or at the site of the lesion at the time of surgery.