Gliomas in rodent whisker barrel cortex: a new tumor model

Object. Surgical treatment of gliomas is difficult because they are invasiv e. Invasion of essential cortex often limits or precludes surgical resectio n. A tumor model was developed in which the rodent whisker barrel cortex wa s used to examine how gliomas affect cortical function and structure. Methods. Both DBT (mouse) and C6 (rat) glioma cell lines were grown in cult ure and labeled with the fluorescent marker Dil in vitro. Labeled turner ce lls were then injected into the whisker barrel cortex of adult mice and rat s. Neurological assessments were made daily and magnetic resonance (MR) ima ges were obtained. Animals were killed by perfusion 6 to 14 days after inje ction, and histological sections were prepared and studied. Tumors were found in all 20 rats and 10 mice that had been injected with th e C6 and DBT cell lines, respectively. The animal cells had been labeled wi th Dil in vitro, and all in vivo tumors proved to be Dil positive. The MR i mages revealed the tumor locations and serial MR images demonstrated tumor growth. Histological evaluation confirmed the location of the tumor and the disruption of barrel cortex architecture. Conclusions. Both DBT and C6 glioma cell lines can be used to generate mali gnant glial turners reproducibly in the whisker barrel cortex. Fluorescent labeling and cytochrome oxidase staining permit visualization of tumor grow th patterns, which disrupt the barrel cortex by microscopic invasion and by gross tissue deformation. Magnetic resonance imaging demonstrates the anat omical extension of these rumors in live rodents. Using this model fur furt her studies on the effects of malignant glioma growth on functional cerebra l cortex should advance our understanding of the neurological issues and ma nagement of patients with these tumors.