[Enhanced metastatic potential of rat RG2 glioblastoma cells transfected with CD44v (meta-1) sequence]

It is extremely rare for brain glioblastoma to metastasize extracranially. To elucidate whether glioblastoma cells remain non-metastatic when ectopically transplanted and CD44v gene is introduced, glioblastoma RG2-m cells were transfected with CD44v gene sequence encompassing v3-v10. After selection in culture medium with G418, CD44v expressing RG2-a cells were cloned. With RG2-a and its parental counterpart RG2-m, a series of experimental metastasis assays were performed in syngeneic F344 rats. When inoculated subcutaneously and in the foot-pad, both RG2-m and RG2-a cells metastasized spontaneously to the regional lymph nodes and lungs. However, metastasis of RG2-a was more severe and more organs were involved when compared to that of the parental RG2-m cells. The results indicate that glioblastoma becomes metastatic if extracranially transplanted and expression of CD44v would further enhance its metastatic patential.