Close monitoring of the implementation of the Dutch national CRC screening program allowed for instant adjustment of the FIT cut-off levels to optimize program performance.
Thirteen human meningiomas were tested for their content of specific somatostatin (SRIH) receptors using an in vitro binding assay with meningioma homogenates as well as receptor autoradiography. All tumors had measurable amounts of somatostatin receptors. Receptor density, however, greatly varied among the tumors, ranging from low levels to more than 400 fmol/mg protein. Seven tumors, biochemically characterized in detail, had saturable and high affinity receptors [mean Kd, 1.10 +/- 0.42 (+/- SEM) nM], with pharmacological specificity for SRIH resembling the noncentral nervous system type of SRIH receptor. There was no correlation between the density of SRIH receptors and the density of progestin receptors measured in parallel. The presence of SRIH receptors in meningiomas was completely unexpected, and their role unknown. If the receptors can mediate antiproliferative properties in meningiomas, as has been suggested to be the case for such receptors in other endocrine tumors, the present data could be of potential therapeutic interest.
We examined whether there is a relationship between body fat mass or body fat distribution and hormonal profiles in the plasma of early pubertal girls. Thirty-five apparently healthy caucasian schoolgirls were selected for Tanner's breast development stage M2; they had all been classified as being stage M1 6 months earlier. Body fat mass had no relationship with the total plasma sex steroid concentration or gonadotropins. However, body fat mass was correlated with the fraction of testosterone that was not bound to sex hormone-binding globulin and considered the fraction available for biological activity. Body fat distribution, rather than body fat mass, was different in relation to the total concentrations of estrone, estradiol (E2), and testosterone as well as the percentage of available E2 or testosterone. Girls with fat localized predominantly on the hips had the highest levels of sex steroids and gonadotropins. It seems likely that this type of fat distribution is a result of ovarian activity. Girls with predominantly abdominal fat were also more obese and showed increased plasma levels of total E2 and a lower androgen/estrogen ratio in plasma, possibly due to increased aromatization, especially in abdominal adipose tissue. The findings suggest a reciprocal relationship among body fat distribution, plasma sex hormone levels, and availability of sex steroids in early female puberty.
Summary Oestrogen (ER) and progestin receptors (PR) were measured in cytosols from histologically normal mammary tissues (n=30), and in benign (n=59) and malignant mammary lesions (n=49) from female dogs. Receptor levels .5 fmol mg-1 protein were considered positive. The presence of histologically normal mammary epithelium within specimens of primary tumours was noticed as a factor that may cause falsepositive receptor results. Receptor levels in non-malignant tissues, and the receptor status of primary cancers did not vary significantly with regard to the phase of oestrous cycle (anoestrus/metoestrus) or the influence of exogenous progestins. ER-or PR-positivity was more frequent and levels of both receptors were higher in 'normal' tissues and in benign lesions than in primary cancers (P<0.001). ER and PR levels were higher in benign lesions of dogs also developing malignant mammary tumours than in benign lesions of dogs that did not (P<0.02 and P<0.05, respectively). Regional and distant cancer metastases were frequently receptornegative. In some dogs heterogeneity of receptor status was found between different sites of the same cancer.These findings indicate that in non-malignant mammary tissues of adult female dogs expression of the genes encoding ER and PR is common. In malignant tumours this property may become lost, in particular in advanced states of disease.Mammary cancer in the dog and in the human have several features in common, including the spontaneous occurrence and the sparing effect of ovariohysterectomy if performed early in life (Schneider et al., 1969, Feinleib, 1968. Oestrogen (ER) and progestin receptors (PR) have been found in a large proportion of mammary cancers in both species (Raynaud et al., 1981;McGuire et al., 1982;Pierrepoint et al., 1984), indicating a role for sex steroid hormones in growth of such tumours. The receptor status of human breast cancer has become established as a useful predictor of the likelihood of response of the disease to endocrine therapy (McGuire et al., 1982) and has also been found to be related to the degree of differentiation (Fisher et al., 1987). These observations may be interpreted as indications that steroid receptor presence in a tumour reflects persistence of normal cell characteristics. It has been difficult, however, to detect substantial amounts of ER in adult normal human breast tissue (Wagner & Jungblut, 1976). This has led to the reverse view, namely, that expression of hormone receptors reflects a feature related to the process of neoplastic transformation (Israel & Band, 1984).The present study was undertaken in order to determine the ER and PR profile of histologically non-affected mammary glands and of benign and malignant (primary and/or metastatic) proliferative lesions in the dog. Results were related to histopathological and some clinical features of affected dogs. Results of a limited number of these determinations have been included in other reports Rutteman et al., , 1988 Those that were not used for ER/PR analysis were always exam...
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