Table 2.
CYP27A1 mRNA expression in tumor tissue and lethal prostate cancer. Shown are case counts and odds ratios for lethal disease with 95% confidence intervals (95% CI). The fourth quartile (highest expression) served as the reference category.
| Quartile of CYP27A1 mRNA expression in tumor tissue | |||||
|---|---|---|---|---|---|
| 1st (lowest) | 2nd | 3rd | 4th (highest) | ptrenda | |
| HPFS | |||||
| Cases: lethal, non-lethal, n | 28, 34 | 20, 45 | 20, 44 | 15, 48 | |
| OR (95% CI), unadjusted | 2.64 (1.23–5.67) | 1.42 (0.65–3.11) | 1.45 (0.66–3.19) | 1 | 0.018 |
| PHS | |||||
| Cases: Lethal, non-lethal, n | 8, 31 | 10, 26 | 10, 27 | 2,b 36 | |
| OR (95% CI), unadjusted | 4.65 (0.92–23.5) | 6.92 (1.40–34.3) | 6.67 (1.35–33.9) | 1 | 0.12 |
|
Combined HPFS and PHS, OR (95% CI) |
|||||
| Model 1: Unadjusted | 2.74 (1.41–5.30) | 2.09 (1.06–4.10) | 2.09 (1.06–4.10) | 1 | 0.005 |
| Model 2: Adjustedc | 3.04 (1.46–6.33) | 2.17 (1.04–4.53) | 2.40 (1.15–5.00) | 1 | 0.007 |
| Model 3: Model 2 + SQLEd | 2.64 (1.24–5.62) | 2.17 (1.03–4.58) | 2.30 (1.08–4.88) | 1 | 0.022 |
| Model 4: Model 2 + cholesterol scored | 2.86 (1.35–6.05) | 2.02 (0.95–4.29) | 2.40 (1.14–5.05) | 1 | 0.015 |
| Model 5: Model 3 + statin use at diagnosis | 2.62 (1.23–5.57) | 2.16 (1.02–4.57) | 2.28 (1.07–4.85) | 1 | 0.023 |
| Model 6: Model 3 + Gleason | 1.76 (0.75–4.17) | 1.84 (0.77–4.41) | 2.05 (0.87–4.86) | 1 | 0.31 |
|
By cholesterol score,e OR (95% CI) |
0.88e | ||||
| Score < median | 2.95 (1.12–7.81) | 1.89 (0.67–5.41) | 1.77 (0.65–4.79) | 1 | 0.032 |
| Score ≥ median | 2.22 (0.89–5.57) | 1.79 (0.72–4.48) | 2.18 (0.85–5.60) | 1 | 0.17 |
Test for linear trend across quartiles, modelled as ordinal indices.
Because of the few events in the reference category for PHS (n = 2), the quartile-based odds ratios for PHS alone should be interpreted cautiously in light of probable sparse-data bias (36).
Adjusted for age (linear), year of diagnosis (categorical), smoking status at cancer diagnosis (binary), body mass index (categorical), high serum cholesterol (binary)
SQLE and summary score of expression levels for all cholesterol synthesis genes were modelled in quartiles.
Analyses stratified by cholesterol synthesis score show unadjusted estimates within levels of the cholesterol summary score for HPFS and PHS combined. The p-value is for multiplicative interaction between CYP27A1 quartile indices (categorical) and cholesterol summary score (binary).