Fig. 2. hDlg degradation by the proteasome in epithelial cancer cells. (A) HPV-16- positive CaSKi, HPV-18-positive HeLa and HPV-negative C33I cervical tumour cells plus HaCaT immortalised skin keratinocytes were treated for either two or four hours with N-CBZ-Leu-Leu-Leu-al (CBZ) proteasome inhibitor before harvesting. Stabilisation of hDlg protein was then assessed by western blot analysis. (B) Comparison of hDlg mRNA levels in CaSKi, HeLa, HaCaT and C33I cells, analysed by RT-PCR amplification (13 cycles) of hDlg mRNA and Southern blot. PhosphoImager scanning of the Southern blot gave the following counts: CaSKi=1335, HeLa=1043, HaCaT=2272, C33I=707. The control was RT-PCR and Southern blot of TBP mRNA.
