Table 2.

Summary of the responses of prostate cancer cells to testosterone withdrawal

Model\Response	VCaP	LNCaP	LAPC4
Cholesterol biosynthesis	minimal change	slight decrease with time	small but persistent decrease
Cholesterol uptake/transport	up-regulation of several receptors after an initial drop	minimal change	minimal change
Delta 4 and delta 5 steroidogenic pathways	significant increase of certain key enzymes, esp. CYP17A1	mostly remain unchanged	slight decrease with time
Backdoor steroidogenic pathway	changes similar to that of Δ4 pathway, except no change in RDH5	minimal change	minimal change
AR expression	increase verified by N-ter and C-ter primers	no change detected by N-ter primer, decrease detected by C-ter primer	same as observed in LNCaP
AR target gene expression	small small decrease followed by gradual recovery with time	slight decrease	significant and progressive decrease with time