Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.7.7 (DNA polymerase)
 17,007 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cytosols of human breast tumours have been assayed for DNA dependent DNA polymerase alpha activity. DNA polymerase alpha activity in benign tumours was found to be significantly lower than in untreated malignant tumours. Biopsy samples removed surgically before and after endocrine therapy showed reduced DNA polymerase alpha activity in 6 out of 9 patients treated with 4-hydroxyandrostenedione, and in 6 out of 7 patients treated with MPA. DNA polymerase alpha activity in malignant breast tumours was higher in oestrogen receptor negative than oestrogen receptor positive tumours.
 ...
PMID:Analysis by DNA polymerase alpha activity of human breast tumour proliferation and the effect of endocrine therapy. 214 78

After a single injection of oestradiol benzoate (1.5 mg/kg) to oestrogen-withdrawn chickens, there was an increase in magnum wet weight, DNA polymerase alpha activity, adenosine-3',5'-monophosphate-dependent protein-kinase activity and estrogen-receptor concentration, as measured over 36 h. Besides these intracellular proteins, the secretory proteins ovalbumin and conalbumin were also augmented, and detailed time-course studies were performed. Early induction kinetics for ovalbumin and conalbumin synthesis, which differed for each protein, were independent of the dose of oestradiol benzoate injected if it exceeded 0.1 mg/kg. After 6 h for ovalbumin and 2 h for conalbumin, the induction curves diverged according to the dose of hormone administered and in correlation with the persistence of elevated nuclear oestrogen-receptor concentrations, a result confirmed with 11 beta-methoxy-17 alpha-ethynyloestradiol (R 2858), a powerful synthetic oestrogen. When oestradiol benzoate (1 mg/kg) and progesterone (3 mg/kg) were injected simultaneously, the rate of conalbumin sythesis, during the first 6-8 h, was lower than that observed in animals injected with oestradiol benzoate alone. However at later times conalbumin synthesis was greater in animals receiving both hormones than with oestradiol alone. In contrast, the rate of ovalbumin synthesis after the combined injection was higher than that induced by either hormone alone throughout the entire experimental period. In order to study further the synergistic and antagonistic activities of these two hormones, a single injection of progesterone (3 mg/kg) was administered 6, 12 or 18 h after 1.5 mg/kg oestradiol benzoate. Progesterone administration resulted in a reduction in cytoplasmic, nuclear and total oestrogen receptor concentration for at least 6 h when compared with the values in birds treated with oestrogen alone. DNA polymerase and protein kinase activities were also reduced during this period. Subsequently, all parameters increased, and by 18-24 h after progesterone treatment, reached values higher than those observed in animals receiving oestrogen alone.
 ...
PMID:Steroid receptors and effects of oestradiol and progesterone on chick oviduct proteins. 624 83

Medroxyprogesterone acetate (MPA) is one of the most commonly prescribed drugs for endocrine therapy of metastatic breast cancer. In this study, the serum MPA concentration was measured by high-performance liquid chromatography (HPLC) and evaluated for its usefulness in predicting the response in 79 cases of advanced or recurrent breast cancers. Overall, 29 patients (37%) achieved an objective response. The response rate correlated significantly with the oestrogen receptor (ER) status (P = 0.03), proliferative activity determined by DNA polymerase alpha (P = 0.04), the disease-free interval (DFI) (P = 0.05) and the serum MPA concentration (P < 0.001). Patients with ER-positive tumours, lower proliferative activity, a longer (DFI) or a higher serum MPA concentration responded more frequently. The mean serum MPA concentration in the responders with ER-positive tumours (P = 0.01) or tumours with a lower proliferative activity (P = 0.008) were significantly lower than in cases with ER-negative tumours or tumours with a higher proliferative activity, respectively. Cases with soft tissue metastases showed responses at significantly lower MPA concentrations (P = 0.003) than those with bone or visceral metastases. Furthermore, there was a dramatic decrease in the MPA concentration when a responder with a high concentration became unresponsive to the therapy. Thus, the serum MPA concentration is a determining factor for the response to treatment.
 ...
PMID:Predictive value of serum medroxyprogesterone acetate concentration for response in advanced or recurrent breast cancer. 933 82