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F K Habib

Publications and source records attributed to F K Habib.

10 recordsLinked to original sources
PubMed1979

Cancer of the prostate: early diagnosis by zinc and hormone analysis?

Zinc, testosterone and dihydrotestosterone concentrations have been measured in normal prostatic tissue and in specimens obtained from untreated patients with benign prostatic hyperplasia (BPH) and carcinoma of the prostate (CaP). The metal--androgen relationship was examined and related to the pathological condition of the patients. The evidence suggests that discriminant analysis combining the hormonal data into a single variable is a reliable test for distinguishing between BPH and CaP patients. We have observed that the high Zn values found in BPH specimens were always associated with a DTH:T ratio greater than 1. Androgen tissue ratios less than 1 were characteristic of all CaP specimens, and these were usually preceded by a reduction in prostatic Zn concentration. Since these patterns, particularly those associated with neoplasia, precede the clinical manifestations, they may be used as an index for predicting the onset of carcinoma in the prostate gland. They may also be of value in monitoring the progress of the disease.

Aged↗
PubMed1979

Effects of tamoxifen on the binding and metabolism of testosterone by human prostatic tissue and plasma in vitro.

The in-vitro metabolism of testosterone in benign and malignant prostatic tissue was examined and distinct quantitative differences between the two types of specimens were observed. The major metabolite of testosterone in the hyperplastic prostate was 5 alpha-dihydrotestosterone and a high 3 alpha(beta)-hydroxysteroid dehydrogenase activity was also detected. In the malignant tissue, 5 alpha-reductase activity was considerably reduced and there was little or no androstanediol formed; the 17 beta-dehydrogenase activity was, however, higher than in the benign tissue. The decrease in 5 alpha-reductase was always followed by a compensatory change in the 3 alpha(beta)-hydroxysteroid dehydrogenase of the malignant prostate. The present study revealed that the ratio of the mean activities of 5 alpha-reductase to 3 alpha(beta)-hydroxysteroid dehydrogenase in the two types of specimen always remained a constant. Although the antioestrogen, tamoxifen, induced an inhibitory effect on the activities of 5 alpha-reductase and 17 beta-hydroxysteroid dehydrogenase in the gland, the present investigation also suggested that tamoxifen stimulated the activity of 3 alpha(3 beta)-hydroxysteroid dehydrogenase. In blood, the action of tamoxifen appeared to be confined to the displacement of androgens from the binding sites on the sex hormone binding globulin.

Aged↗
PubMed1976

Androgen levels in the plasma and prostatic tissues of patients with benign hypertrophy and carcinoma of the prostate.

Specific radioimmunoassays for testosterone, dihydrotestosterone (DHT) and androstenedione were carried out to measure the concentrations of the three hormones in the plasma and prostatic tissue of ten patients with benign prostatic hypertrophy (BPH) and ten patients with carcinoma of the prostate. The results indicate that there are no significant differences between the peripheral plasma concentrations of testosterone, DHT and androstenedione in BPH [19.7 +/- 2.6, 2.6 +/- 0.9 AND 5.5 +/- 1.7 (S.E.M.) nmol/l respectively] and in carcinoma [16.9 +/- 2.8, 2.4 +/- 0.5, 4.4 +/- 1.1 nmol/l respectively], (in all cases P greater than 0.1). In contrast, the prostate tissue rations DHT: testosterone (3.59 +/- 0.55 for BPH and 0.66 +/- 0.09 for carcinoma) and androstenedione: testosterone (2.83 +/- 0.38 for BPH and 1.07 +/- 0.16 for carcinoma) are significantly less in carcinoma than in benign hypertrophy ( in all cases P less than 0.01). The accumulation of testosterone in the carcinoma, relative to values found in BPH tissue is, therefore, not associated with changes in the concentrations of androgens in the plasma pool but may be related to local factors and metabolic changes within the prostate.

Aged↗
PubMed1976

Metal-androgen interrelationships in carcinoma and hyperplasia of the human prostate.

Zinc and cadmium concentrations were measured by atomic absorption spectroscopy in normal and pathological human prostates. Our studies confirm the values of zinc in normal tissue [6.84 +/- 1.21 (S.E.M.) mumol/g] and benign prostatic hypertrophy (BPH) (6.9 +/- 1.19 mumol/g) are similar, while in neoplastic tissues zinc concentrations were significantly lower (2.61 +/- 0.45 mumol/g). The Cd2+ levels in BPH (23.11 +/- 3.28 nmol/g) were, on the other hand, considerably higher than those found for normal tissues (5.15 +/- 0.62 nmol/g). In agreement with other published reports, Cd2+ concentrations were found to be markedly increased in carcinomatous tissue (129.79 +/- 22.22 nmol/g). No correlation was however established between the values for the two metals in either type of prostatic tissue. An established specific radioimmunoassay was used for the measurement of testosterone and dihydrotestoesterone (DHT) and a distinct pattern emerged upon comparing these results with those for the zinc and cadmium concentrations. It appears that the concentrations of DHT in benign hypertrophy and of testosterone and DHT in carcinoma were inversely proportional to the levels of Zn2+ in abnormal tissue. In contrast, the DHT levels in the hypertrophied and malignant tissue were proportional to the Cd2+ concentrations.

Adult↗