[Evaluation of binding of FITC-prolactin conjugate to prolactin receptor]

Prolactin is an important mammalian hormone and the associated receptor is recognized in many different cells. Radioligand and histochemical methods are both used for assaying prolactin receptor. To produce FITC-prolactin conjugate and also to study the ability of conjugate to bind prolactin receptor. In this experimental study FITC was bound to prolactin in alkaline solution. FITC-prolactin conjugate was separated from free FITC by chromatographic method. Later, the ability of FITC-prolactin conjugate to bind prolactin receptor of peripheral blood mononuclear cells [PBMC] was assessed by flowcytometry. Fluorescence emission was detected in 2.1% of the cells in absence of FITC-prolactin. Following the addition of FITC-prolactin conjugate to cells for one hour and further washing, the fluorescence emission was detected in 27.8% of cells. For PBMC, these data were 0.02% and 11.8%, respectively. Regarding the data obtained in our study, FITC-prolactin conjugate can bind prolactin receptor. Therefore, this conjugate could be used for assessing prolactin receptor by fluorometric method

[Survey of the status of estrogen and prolactin receptors in breast cancer]

The existence of hormonal receptors in cancer cells is very important in various aspects. Survey of the status of estrogen receptors [ERs] in the evaluation of breast cancer cells is important due to their response to hormonal therapy. Many studies have been recently carried out on prolactin receptors [PRLRs] especially in breast cancer. The aim of the present study was survey of the status of ERs and PRLRs in breast cancer. In this cross-sectional study 40 samples from breast cancer tumors were studied. Estrogen receptor was assessed by radio-ligand binding assay method. Free and total prolactin receptors were also measured using iodinated prolactin [[125]I-PRL]. Magnesium chloride solution [3.5 M] was used to assay the total prolactin receptor. Eighty five percent of tumor samples were ductal tubular carcinoma. In 62.5%, 45% and 62.5% of tumor samples ER, free PRLR and total PRLR were observed respectively. Forty Five percent of the tumor cells expressed both ER and total PRLR. A positive significant relation between ER and free PRLR was observed [p<0.05]. There was also a significant relation [p<0.05] between ER and total PRLR. Twenty Percent of tumor cells expressed neither ER nor total PRLR. Since the existence of estrogen and prolactin receptors in breast tumor cells have been shown, application of antiestrogenic and antiprolactin drugs in the inhibition of these tumors growth are possibly of value