Table 2.
5α-Reductase, 20α-HSO and 3α-HSO activities in microsomes/cytosol of breast cell lines.
| Cells | 5αR | 20α-HSO (reductive) | 3α-HSO (reductive) | 5αR/20α-HSO | 5αR/3α-HSO |
| MCF-7 | 228.6 (86.5) | 17.9 (6.8) | 17.9 (6.8) | 12.77 | 12.77 |
| MDA231 | 186.2 (75.3) | 49.8 (20.1) | 11.3 (4.6) | 3.74 | 16.48 |
| T-47D | 82.1 (74.5) | 21.8 (19.8) | 6.3 (5.7) | 3.77 | 13.03 |
| MCF-10A | 78.3 (7.6) | 845.1 (81.4) | 114.2 (11.0) | 0.93 | 0.69 |
The 10,000 × g supernatant of cell homogenates was incubated with NADH, NADPH and [3H]progesterone, and enzyme activities were determined by quantifying metabolites formed as a result of specific enzyme actions (See Methods for details). Values (mean from two experiments) are given as pg/hour/mg protein; the values in brackets show the percent of total enzyme activities for a particular cell type.