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METABOLISM OF TESTOSTERONE BY HUMAN BREAST TUMOURS
513
METABOLISM OF TESTOSTERONE BY HUMAN BREAST TUMOURS
(see accompanying table, patients 1-5) and 5 with malignant (nos. 6-10). In the patients with carcinomas,
tumours
S. ASH
J. S. JENKINS
from the tumour and shown to be free from histologically malignancy was also used for comparison. The tissue was finely minced and 0-5 g. was incubated in duplicate for 6 hours at 37 °C in Eagle’s medium containing 100 nCi (4-14C) testosterone (sp. act. 58-2 mCi/mmol.), and N.A.D.P.H. in a concentration of 0-5 niM. The radioactive metabolites were separated by paper and thin-layer chromatography, and identified by recrystallisation to constant specific activity and gasliquid chromatography according to methods previously described.6
breast tissue
Department of Medicine, St. George’s Hospital, London S.W.1
Summary
Materials and Methods Tissue was obtained from 5 patients with benign tumours
Breast tumours metabolised testosterone in vitro to androstenedione
and the potent androgen 5&agr;-dihydrotestosterone. The formation of this metabolite was greatest in the most undifferentiated carcinomas and was not found in normal breast tissue.
Results
Introduction
IT is well recognised that testosterone can influence the growth of the female breast, and the excretion of androgen metabolites in the urine of patients with breast carcinoma has been extensively studied with a view to predicting the response to treatment by endocrine ablation.1 The prognostic value of this approach is not always very precise, and more direct methods for assessing the relation of tumour growth to androgens is desirable. Adams and Wong2 reported that breast tumour tissue itself could metabolise androgenic steroids in vitro, and Jones et al.3s have shown that human mammary carcinoma tissue can transform testosterone to 5oc-dihydrotestosterone. Particular interest lies in the formation of 5oc-dihydrotestosterone, since its androgenic activity is known to be equal to, if not greater than, that of the parent substance. This metabolite is now thought to be of considerable biological importance in determining the androgenic activity of testosterone in tissues such The possibility arises that as prostate 4 and skin.S the local hormonal environment of the breast tumour, and hence its subsequent progress, may be determined by the metabolic activity of the tumour. The following experiments were therefore performed to determine the extent to which human mammary tumours, both benign and malignant, metabolised testosterone in vitro, and an attempt was made to correlate the formation of metabolites with the histo-
logical
appearances of the tumour. METABOLISM OF
remote
(4-C)
Normal breast tissue and benign and malignant all oxidised testosterone at the 17p-hydroxyl position to form 64-androstenedione (androst-4-ene3,17-dione). There were no consistent differences in 17-dehydrogenase activity between the three groups of tissues (see table). In contrast, 5
tumours
sterone
(17p-hydroxy-5o:-androstan-3-one)
was
pro-
duced by 4 out of 5 malignant tumours and 3 out of 5 benign tumours, but was not found in the incubations of normal breast tissue. 5«-reduction of testosterone was greatest in the two most cellular and most undifferentiated carcinomas (patients 6 and 8), and less so or absent in the 3 carcinomas where histologically there 2 of these patients was much more fibrous reaction. with scirrhous tumours (7 and 9) had previously received radiotherapy to the tumour, and patient 10 was
elderly. Discussion
These results indicate that breast tumours metabolise to the biologically active androgen 5fx-dihydrotestosterone, and it appeared that the greatest degree of conversion occurred in the most undifferentiated tumours. It is not likely that this activity was due simply to a greater cellularity of these tumours, since all tissues showed an equal facility to metabolise testosterone to androstenedione. Likewise there was no correlation between the degree of lymphocytic response in the tumour and the metabolic activity. testosterone
TESTOSTERONE BY HUMAN BREAST TISSUE
514
of their histological appearances, the showing the greatest degree of 5
From the
nature
tumours
We thank the Medical Research Council for a grant in support of this work; Prof. W. B. Robertson for the histological assessments ; and Mr. J.-C. Gazet for providing the breast tissue. REFERENCES
1. Bulbrook, R. D., Greenwood, F. C., Hayward, J. L. Lancet, 1960, i, 1154. 2. Adams, J. B., Wong, M. S. F.J. Endocr. 1968, 41, 41. 3. Jones, D., Cameron, E. H. D., Griffiths, K., Gleave, E. N., Forrest, A. P. M. Biochem. J. 1970, 116, 919. 4. Bruchowsky, N., Wilson, J. D. J. biol. Chem. 1968, 243, 2012. 5. Wilson, J. D., Walker, J. D. J. clin. Invest. 1969, 48, 371. 6. Jenkins, J. S., Ash, S.J. Endocr. 1971, 49, 515. 7. Champion, H. R., Wallace, I. W. J., Prescott, R. J. Br. J. Cancer,
1972, 26,
129.
their broad-spectrum bactericidal activity, their low
sensitivity
to
penicillinase-producing
organisms,
minimal cross-sensitivity in penicillin-allergic subjects, and in general their low toxicity. Concern, however, exists regarding their nephrotoxicity. Cephaloridine, which is the most active cephalosporin, has been implicated as a potentially nephrotoxic agent in many and as a definite nephrotoxic agent in certain animals.4-7 Foord,8 however, in a review of 36 cases of acute oliguric renal failure, in which cephaloridine was suspected as an aetiological agent, considered that prior renal damage, prerenal azotaemia, administration of other nephrotoxic agents, the use of potent diuretics, and excessive dosage were major factors in producing acute renal failure in these subjects. In view of the potential value of cephaloridine in the treatment of refractory urinary infection9 we decided to investigate renal function in patients undergoing treatment for recurrent urinary infection, using cephaloridine in normal therapeutic dosage.
cephaloridine
Patients and Methods Ten
ABSENCE OF NEPHROTOXICITY DURING CEPHALORIDINE THERAPY FOR URINARY-TRACT INFECTION A. C. KENNEDY J. F. WINCHESTER and the Renal Unit, Medicine University Department of Royal Infirmary, Glasgow G4 0SF Summary
Renal function
was
monitored in
ten
patients receiving cephaloridine for refractory urinary infection. Serial levels of serumcephaloridine were taken. No adverse effects on renal function were observed, although transient mild reductions in urinary sodium and potassium excretion noted. Plasma-renin levels did not alter with therapy. It is suggested that no adverse effects on renal function should be encountered if serum levels of cephaloridine are maintained between 20 and 80 µg. per ml. were
Introduction a
ANTIBIOTICS of the cephalosporin group have found major place in modern therapeutics by virtue of
patients (nine female, one male) with recurrent urinary-tract infection were admitted to hospital during the study. Informed consent for the study was obtained in all cases. All had attended the renal clinic at the Royal Infirmary, Glasgow, for a number of years and were known to have stable renal function. Their details are given in table I. Four patients had normal urinary tracts (as judged on previous intravenous pyelography), with normal renal function; four patients had abnormal urinary tracts with normal renal function; and the remaining two patients had abnormal urinary tracts with reduced renal function. All had two positive urine cultures (over 100,000 organisms per ml. of urine) estimated by the quantitative technique of McGeachie and Kennedy 10 prior to therapy. Renal function was studied before cephaloridine therapy and throughout the course of therapy. Endogenous creatinine clearance (corrected for surface area) was measured by the method of Hare 11 before, during, and on the last day of therapy. Quantitative 24-hour proteinuria was estimated by biuret method, before and during therapy, in all patients. Urinary sediment was examined by a modified Addis technique,’and red cells, white cells, and casts were counted. Haematological indices were obtained by Coulter-S-counter and serum-protein, plasma-urea, and electrolyte values by TechniconAutoAnalyzer ’, and serum-transaminases on a reaction-rate analyser. Urinary
TABLE I-DETAILS OF PATIENTS UNDERGOING CEPHALORIDINE THERAPY FOR RECURRENT URINARY-TRACT INFECTION
METABOLISM OF TESTOSTERONE BY HUMAN BREAST TUMOURS
(see accompanying table, patients 1-5) and 5 with malignant (nos. 6-10). In the patients with carcinomas,
tumours
S. ASH
J. S. JENKINS
from the tumour and shown to be free from histologically malignancy was also used for comparison. The tissue was finely minced and 0-5 g. was incubated in duplicate for 6 hours at 37 °C in Eagle’s medium containing 100 nCi (4-14C) testosterone (sp. act. 58-2 mCi/mmol.), and N.A.D.P.H. in a concentration of 0-5 niM. The radioactive metabolites were separated by paper and thin-layer chromatography, and identified by recrystallisation to constant specific activity and gasliquid chromatography according to methods previously described.6
breast tissue
Department of Medicine, St. George’s Hospital, London S.W.1
Summary
Materials and Methods Tissue was obtained from 5 patients with benign tumours
Breast tumours metabolised testosterone in vitro to androstenedione
and the potent androgen 5&agr;-dihydrotestosterone. The formation of this metabolite was greatest in the most undifferentiated carcinomas and was not found in normal breast tissue.
Results
Introduction
IT is well recognised that testosterone can influence the growth of the female breast, and the excretion of androgen metabolites in the urine of patients with breast carcinoma has been extensively studied with a view to predicting the response to treatment by endocrine ablation.1 The prognostic value of this approach is not always very precise, and more direct methods for assessing the relation of tumour growth to androgens is desirable. Adams and Wong2 reported that breast tumour tissue itself could metabolise androgenic steroids in vitro, and Jones et al.3s have shown that human mammary carcinoma tissue can transform testosterone to 5oc-dihydrotestosterone. Particular interest lies in the formation of 5oc-dihydrotestosterone, since its androgenic activity is known to be equal to, if not greater than, that of the parent substance. This metabolite is now thought to be of considerable biological importance in determining the androgenic activity of testosterone in tissues such The possibility arises that as prostate 4 and skin.S the local hormonal environment of the breast tumour, and hence its subsequent progress, may be determined by the metabolic activity of the tumour. The following experiments were therefore performed to determine the extent to which human mammary tumours, both benign and malignant, metabolised testosterone in vitro, and an attempt was made to correlate the formation of metabolites with the histo-
logical
appearances of the tumour. METABOLISM OF
remote
(4-C)
Normal breast tissue and benign and malignant all oxidised testosterone at the 17p-hydroxyl position to form 64-androstenedione (androst-4-ene3,17-dione). There were no consistent differences in 17-dehydrogenase activity between the three groups of tissues (see table). In contrast, 5
tumours
sterone
(17p-hydroxy-5o:-androstan-3-one)
was
pro-
duced by 4 out of 5 malignant tumours and 3 out of 5 benign tumours, but was not found in the incubations of normal breast tissue. 5«-reduction of testosterone was greatest in the two most cellular and most undifferentiated carcinomas (patients 6 and 8), and less so or absent in the 3 carcinomas where histologically there 2 of these patients was much more fibrous reaction. with scirrhous tumours (7 and 9) had previously received radiotherapy to the tumour, and patient 10 was
elderly. Discussion
These results indicate that breast tumours metabolise to the biologically active androgen 5fx-dihydrotestosterone, and it appeared that the greatest degree of conversion occurred in the most undifferentiated tumours. It is not likely that this activity was due simply to a greater cellularity of these tumours, since all tissues showed an equal facility to metabolise testosterone to androstenedione. Likewise there was no correlation between the degree of lymphocytic response in the tumour and the metabolic activity. testosterone
TESTOSTERONE BY HUMAN BREAST TISSUE
514
of their histological appearances, the showing the greatest degree of 5
From the
nature
tumours
We thank the Medical Research Council for a grant in support of this work; Prof. W. B. Robertson for the histological assessments ; and Mr. J.-C. Gazet for providing the breast tissue. REFERENCES
1. Bulbrook, R. D., Greenwood, F. C., Hayward, J. L. Lancet, 1960, i, 1154. 2. Adams, J. B., Wong, M. S. F.J. Endocr. 1968, 41, 41. 3. Jones, D., Cameron, E. H. D., Griffiths, K., Gleave, E. N., Forrest, A. P. M. Biochem. J. 1970, 116, 919. 4. Bruchowsky, N., Wilson, J. D. J. biol. Chem. 1968, 243, 2012. 5. Wilson, J. D., Walker, J. D. J. clin. Invest. 1969, 48, 371. 6. Jenkins, J. S., Ash, S.J. Endocr. 1971, 49, 515. 7. Champion, H. R., Wallace, I. W. J., Prescott, R. J. Br. J. Cancer,
1972, 26,
129.
their broad-spectrum bactericidal activity, their low
sensitivity
to
penicillinase-producing
organisms,
minimal cross-sensitivity in penicillin-allergic subjects, and in general their low toxicity. Concern, however, exists regarding their nephrotoxicity. Cephaloridine, which is the most active cephalosporin, has been implicated as a potentially nephrotoxic agent in many and as a definite nephrotoxic agent in certain animals.4-7 Foord,8 however, in a review of 36 cases of acute oliguric renal failure, in which cephaloridine was suspected as an aetiological agent, considered that prior renal damage, prerenal azotaemia, administration of other nephrotoxic agents, the use of potent diuretics, and excessive dosage were major factors in producing acute renal failure in these subjects. In view of the potential value of cephaloridine in the treatment of refractory urinary infection9 we decided to investigate renal function in patients undergoing treatment for recurrent urinary infection, using cephaloridine in normal therapeutic dosage.
cephaloridine
Patients and Methods Ten
ABSENCE OF NEPHROTOXICITY DURING CEPHALORIDINE THERAPY FOR URINARY-TRACT INFECTION A. C. KENNEDY J. F. WINCHESTER and the Renal Unit, Medicine University Department of Royal Infirmary, Glasgow G4 0SF Summary
Renal function
was
monitored in
ten
patients receiving cephaloridine for refractory urinary infection. Serial levels of serumcephaloridine were taken. No adverse effects on renal function were observed, although transient mild reductions in urinary sodium and potassium excretion noted. Plasma-renin levels did not alter with therapy. It is suggested that no adverse effects on renal function should be encountered if serum levels of cephaloridine are maintained between 20 and 80 µg. per ml. were
Introduction a
ANTIBIOTICS of the cephalosporin group have found major place in modern therapeutics by virtue of
patients (nine female, one male) with recurrent urinary-tract infection were admitted to hospital during the study. Informed consent for the study was obtained in all cases. All had attended the renal clinic at the Royal Infirmary, Glasgow, for a number of years and were known to have stable renal function. Their details are given in table I. Four patients had normal urinary tracts (as judged on previous intravenous pyelography), with normal renal function; four patients had abnormal urinary tracts with normal renal function; and the remaining two patients had abnormal urinary tracts with reduced renal function. All had two positive urine cultures (over 100,000 organisms per ml. of urine) estimated by the quantitative technique of McGeachie and Kennedy 10 prior to therapy. Renal function was studied before cephaloridine therapy and throughout the course of therapy. Endogenous creatinine clearance (corrected for surface area) was measured by the method of Hare 11 before, during, and on the last day of therapy. Quantitative 24-hour proteinuria was estimated by biuret method, before and during therapy, in all patients. Urinary sediment was examined by a modified Addis technique,’and red cells, white cells, and casts were counted. Haematological indices were obtained by Coulter-S-counter and serum-protein, plasma-urea, and electrolyte values by TechniconAutoAnalyzer ’, and serum-transaminases on a reaction-rate analyser. Urinary
TABLE I-DETAILS OF PATIENTS UNDERGOING CEPHALORIDINE THERAPY FOR RECURRENT URINARY-TRACT INFECTION