Table 8. Feasibility of short-term in vitro expansion and 
transduction of fresh renal tumor explants. Fresh renal tumor 
explants from 7 different patients have been grown in vitro over a 
4-6 week period and have been transduced with the E.Coli Beta- 
galactosidase marker gene between passages 1 and 5. All of the 
tumors listed in this table were grown and transduced at Johns 
Hopkins Oncology Center. Of note, in vitro expansion and 
transduction efficiency does not seem to be determined by the 
histologic subtype or nuclear grade of the explanted renal tumor. 
RCC CODE 
LAST IN VITRO HISTOLOGY 
PASSAGE 
TRANSDUCTION 
EFFICIENCY 
RCC 
3.8.91 
P6 
Papillary + 
clear cell and 
granular cell 
features 
RCC 
5.1.91 
P7 
Grade II Clear 
cell 
RCC 
6.25.91 
P4 
Granular cell 
RCC 
7.9.91 
P7 
Clear cell. 
Grade II 
RCC 
10.14.91 
P5 
Sarcomatoid 
RCC 
10.14.91 VC 
P4 Then 
transformed to 
a cell line 
Sarcomatoid 
RCC 
10.25.91 
P5 
Grade II, clear 
cell 
100 . 0 % 
100 . 0 % 
78.0% 
64.0% 
59.3% 
86.4% 
39.7% 
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