Imaging of whole tumor cut sections using a novel scanning beam confocal fluorescence MACROscope (R)

Hypoxia caused by inadequate structure and function of the tumor vasculatur e has been found to negatively determine the prognosis of cancer patients. Hence, understanding the biological basis of tumor hypoxia is of significan t clinical interest. To study solid tumor microenvironments in sufficient d etail, large areas (several mm in diameter) need to be imaged at mum resolu tions. We have used a novel confocal scanning laser MACROscope (R) (CSLM) c apable of acquiring images over fields of view up to 2 cmX2 cm. To demonstr ate its performance, frozen sections from a cervical carcinoma xenograft we re triple labeled for tissue hypoxia, blood vessels and hypoxia-inducible t ranscription factor 1 alpha (HIF-1 alpha), imaged using the CSLM and compar ed to images obtained using a standard epifluorescence microscope imaging s ystem. The results indicate that the CSLM is a useful instrument for imagin g tissue-based fluorescence at resolutions comparable to standard low-power microscope objectives. (C) 2001 Society of Photo-Optical Instrumentation E ngineers.