Biological and clinical relevance of proliferative activity in inflammatory breast-cancer.

The hormone receptor status and proliferative activity characteristics of inflammatory breast cancer (IBC) were studied in a series of 46 patients. ER and PgR were measured by the DCC method and proliferative activity was by the H-3-thymidine autoradiographic labeling index (H-3-Tdr-LI). Tumors were ER and PgR positive in 42% and 38% of cases, respectively, whereas median H-3-Tdr-LI was 3.8%. With regard to clinical aspects, overall survival (OS) was not affected by either ER status (36 cases) or H-3-Tdr-LI value (33 cases). On the contrary, PgR(+) status was able to individualize women with a significantly higher probability of OS (X(2) by long rank test, p=0.03) after 35 months of follow-up. In the subgroup of 14 patients subjected to double biopsy performed before and after administration of primary polychemotherapy, the tumor proliferative activity variations were not related to clinical outcome

GnRH receptors in human breast cancer and its contiguous not-involved breast tissue.

The present study was undertaken to evaluate the presence of GnRH receptors (GnRH-R) in breast cancer and not-involved breast tissue, and the relationships between GnRH-R and receptors for estrogen (ER) and progesterone (PgR) in the same tissues. Utilizing a tritiated natural GnRH in order to assay the native receptor binding we analyzed the level of binding sites for GnRH in membranes derived from 90 breast tumors and in 40 cases from neighboring, not-involved breast tissue. GnRH-R was found both in cancer and normal tissues. The prevalence for GnRH-R was higher in tumor than in not-tumor tissue (45% vs 39%, respectively), but the overall levels were not significantly different (15.9+/-24 fmol/mg protein vs 18.2+/-39 fmol/mg protein, respectively). The only statistically different content of GnRH-R we found concerned PgR negative vs PgR positive tumor tissues (mean content: 23 vs 11 fmol/mg protein, respectively in PgR- and PgR+ tumors, p=0.03 by t test); furthermore the proportion of GnRH-R positive cases in the tumor resulted significantly higher in premenopausal patients vs postmenopausal (56% vs 32%, by Chi square test, p<0.05). The GnRH receptors status of primary tumor and contiguous not-involved breast tissue resulted associated (overall agreement: 63%, p<0.05) but no specific steroid patterns for GnRH-R positivity was observed

Characterization of a h-3 GnRH method for the measurement of GnRH binding-sites in human breast-cancer and breast-cancer cell-lines.

The peptide hormone, GnRH has been hypothesized to play a direct antitumoral role in certain kinds of breast cancer. This direct effect is considered to function via high affinity membrane receptors to GnRH that have been demonstrated in tumors. However, no routine assay for GnRH receptors exist limiting further research in elucidating the mechanisms of GnRH action during treatment and both the clinical usefulness of this measure and the development or refinement of GnRH treatments. Part of the problem has been that previously reported procedures require expensive, difficult (for routine clinical laboratories) iodination of specific GnRH analogs. The use of iodinated substrates present the additional problems of radioactive waste disposal and safety of laboratory personal. Further, the use of different analogs complicates the comparison of data between laboratories. We present an assay that utilizes tritiated natural GnRH in order to assay the native receptor binding and reduce both safety problems and cost of assay/waste disposal. The use of nitrocellulose filters treated overnight with 1% BSA resolved the problems of high blank values. Kinetic data demonstrate that this assay is sensitive, accurate and give results comparable with other methods. We also show that the membranes derived from the tumor and the cell cultures may be frozen at -80 degrees C for up to 90 days without affecting the results of the assa

Characterization of a h-3 GnRH method for the measurement of GnRH binding-sites in human breast-cancer and breast-cancer cell-lines.

The peptide hormone, GnRH has been hypothesized to play a direct antitumoral role in certain kinds of breast cancer. This direct effect is considered to function via high affinity membrane receptors to GnRH that have been demonstrated in tumors. However, no routine assay for GnRH receptors exist limiting further research in elucidating the mechanisms of GnRH action during treatment and both the clinical usefulness of this measure and the development or refinement of GnRH treatments. Part of the problem has been that previously reported procedures require expensive, difficult (for routine clinical laboratories) iodination of specific GnRH analogs. The use of iodinated substrates present the additional problems of radioactive waste disposal and safety of laboratory personal. Further, the use of different analogs complicates the comparison of data between laboratories. We present an assay that utilizes tritiated natural GnRH in order to assay the native receptor binding and reduce both safety problems and cost of assay/waste disposal. The use of nitrocellulose filters treated overnight with 1% BSA resolved the problems of high blank values. Kinetic data demonstrate that this assay is sensitive, accurate and give results comparable with other methods. We also show that the membranes derived from the tumor and the cell cultures may be frozen at -80 degrees C for up to 90 days without affecting the results of the assay.info:eu-repo/semantics/publishe