EGF stimulates anchorage-independent growth of a human bladder carcinoma cell line (KU1) with an amplified and over-expressed EGF receptor gene
✍ Scribed by Jiro Ishikawa; Sakan Maeda; Taketoshi Sugiyama; Ryuichiro Nishimura; Akira Mizoguchi; Sadao Kamidono
- Publisher
- John Wiley and Sons
- Year
- 1989
- Tongue
- French
- Weight
- 695 KB
- Volume
- 44
- Category
- Article
- ISSN
- 0020-7136
No coin nor oath required. For personal study only.
✦ Synopsis
Southern blot analysis of 6 human bladder carcinoma cell lines revealed amplification of the epidermal growth factor receptor (EGFR) gene in the KUI cell line. The amplification of the gene was about 4-fold as compared with that of human placental DNA. Several restriction endonuclease digestions revealed that there was no gross rearrangement of the EGFR gene in KU I. Northern blot analysis showed normal 10 and 5.6 kb of EGFR gene-related mRNA species. '2sI-EGF binding revealed 2 distinct EGF binding sites on KUI cells: high-affinity sites 5.7 X los receptors per cell with 1.1 nM & and lowaffinity sites 2.3 X lo6 receptors per cell with 7.4 nM &. The number of the EGFR was compatible with that of the A431 squamous carcinoma cell line which has an amplified, rearranged and over-expressed EGFR gene. Solid-phase immunoisolation analysis showed a single 170 kDa EGFR protein in KU I as well as in A43 I. Unlike other cell lines with amplified and over-expressed EGFR gene, anchorage-dependent growth of KUI was stimulated but not inhibited by EGF. Moreover, anchorage-independent growth of KU I was stimulated by EGF.