Expression of 5α-reductase type 1 in breast cancer and adjacent non-malignant tissue: an immunohistochemical study
Bibliographic record
Abstract
Intratumoral biosynthesis of sex steroids is thought to play a role in the pathogenesis and development of human breast cancer. There is evidence that androgens can inhibit the development and progression of breast cancer. Among the enzymes involved in the biosynthesis of androgens, 5α-reductase plays a key role by reducing testosterone to dihydrotestosterone, the most potent androgen. Two isoforms of 5α-reductase have been characterized and 5α-reductase type 1 is predominant in breast cancer tissue. We developed specific antibodies to 5α-reductase type 1 and studied the expression of the enzyme in 84 specimens of breast carcinoma and adjacent non-malignant tissues by immunohistochemistry. The results were correlated with the expression of androgen receptor, estrogen receptor α, progesterone receptor and CDC47, a cell division marker as well as the tumor stage, tumor size, nodal status and menopausal status. The expression of 5α-reductase type 1 in 61% of breast cancer specimens appeared significantly lower than that observed in normal adjacent tissues (87% of cases being positive). There was no significant correlation between 5α-reductase type 1 expression and the clinicopathological parameters studied. The decrease in 5α-reductase type 1 expression in breast cancer as compared to that observed in the adjacent normal tissues could play a role in the development and/or progression of the cancer by modifying the intratumoral levels of androgens.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".