Increased expression of prolactin receptor gene assessed by quantitative polymerase chain reaction in human breast tumors versus normal breast tissues

The role of PRL in human breast tumorigenesis is not well understood. One of the limitations is the difficulty of accurately measuring PRL receptors (PRLR) in human tissues. We established a quantitative PCR method (Q-PCR) in T-47D human breast cancer cells and applied it to 29 patients, 25 of whom presented with either cancer or fibroadenoma. Four patients underwent a mammoplasty, and normal epithelial cells were cultured before Q-PCR. In T-47D cells, 31 x 10(6) messenger RNA molecules were detected per microgram of total RNA. In all patients, expression of the PRLR gene was detected, varying from 1500 to 1 x 10(6) molecules/microgram of RNA in normal tissues and from 4500 to 34.7 x 10(6) molecules/microgram of RNA in tumors. PRLR expression was always greater in tumor than in normal contiguous tissue and similar in cultured mammary epithelial cells and normal breast tissues. Estradiol and progesterone receptor-negative tumors expressed low levels of PRLR transcripts, similar to normal breast tissue from menopausal women. Immunocytochemical analysis of PRLR confirmed stronger staining in almost all tumor samples compared with normal tissues. A messenger RNA encoding locally produced human PRL was also identified by RT-PCR in every sample tested. Our results confirm PRLR gene expression in all tissues studied, and moreover, indicate that this expression is increased in human breast tumors vs. normal contiguous tissues.

Effect of subtotal nephrectomy on the excretion of urinary alanine aminopeptidase and gamma glutamyltransferase in the male Wistar rat. A long-term study

The study of alanine aminopeptidase (AAP) and gamma glutamyltransferase (GGT), two integral components of the brush border membrane of the proximal kidney tubule, has generated considerable interest for research on the nephrotoxicity of drugs. AAP and GGT activity in urine correlate strongly. The three phases after a subtotal nephrectomy can be described as follows: the first phase, lasting 1 month, is characterized by an abrupt decrease of 70% in AAP and GGT activity, corresponding to the excised kidney mass. During the second phase, a partial recovery occurs representing nearly 50% of the AAP and GGT activity in the control group (30th to the 75th day after nephrectomy). These activities begin to decrease slightly in the third phase until the end of the experiment. In terms of remaining kidney mass, the results demonstrate a twofold increase of the AAP and GGT activity. The same phenomenon can be seen in the excretion of creatinine, except that the compensatory activity is multiplied by four in the remaining kidney. Good correlations between AAP activity, GGT activity, urinary creatinine, 24-hour urine volume, and 24-hour creatinine output are found in both experimental and control groups.

Comparative study of alanine-amino-peptidase and gamma-glutamyl-transferase activity in normal Wistar rat urine

24 h urinary alanine-amino-peptidase (AAP) and gamma-glutamyl transferase (GGT) activities were studied from the 3rd-7th month of life in male Wistar rats. A close relationship was found between AAP and GGT activity, except at the beginning and at the end of this period. At the end there appear 2 subgroups, the larger (70%) showing a strong correlation between AAP and GGT activity and the other (30%), demonstrating no correlation at all. A good correlation between AAP and GGT activities, creatinine, 24 h urine volume and 24 h creatinine output was found.

A cytoplasmic gene for partial suppression of a nuclear pleiotropic respiratory deficient mutant in the petite negative yeast Schizosaccharomyces pombe

The nuclear pleiotropic respiratory-deficient mutant pet1 (previously M126) exhibits cytochromes aa3 and b deficiencies accompanied by loss of the oligomycin-sensitivity of the mitochondrial ATPase. The mutant pet1, unable to grow on glycerol, growth on glucose. The latter phenotypic trait symbolized by ANAS-D, exhibits a high frequency (2 to 4 X 10(5)) Of spontaneous suppression into Antimycin A-resistant strains. Mutagenesis with MnCl2 increases by a factor of 10(2) the frequency of ANAR-D derivatives. This suppression is partial since none of the suppressed strains is able to grow on glycerol even when respiratory functions and cytochromes activities are restored as in the pet1 [SUP2] strain. In the latter strain it is concluded that the extralocus suppressor gene [SUP2] is responsible for the ANAR-D trait. Tetrad analysis in a cross homozygous for pet1 demonstrates a non-Mendelian segregation pattern for the SUP2 suppressor gene. In stable diploids, homozygous for pet1, the [SUP2] suppressor exhibits a mitotic segregation pattern. Furthermore the transmission of the [SUP2] gene is decreased by ethidium bromide treatment. Therefore, the [SUP2] suppressor gene responsible for partial suppression of the nuclear pleiotropic phenotype in mutant pet1 is of cytoplasmic heredity.