Identification of a protein factor secreted by 3T3-L1 preadipocytes inhibitory for the human MCF-7 breast cancer cell line.

The 3T3-L1 cell line is a preadipocyte cell line derived from the Swiss 3T3 mouse fibroblast cell line. We have compared the effect of 3T3-L1 conditioned medium (3T3-L1 CM) and Swiss 3T3 conditioned medium (3T3 CM) on the growth of normal mouse mammary cells (NMMG) and the human MCF-7 breast carcinoma cell line. 3T3 CM increased the growth of both NMMG and MCF-7 cells by 19 +/- 2% (SD) and 24 +/- 3%, respectively, and increased thymidine incorporation by 74 +/- 4% and 104 +/- 8%, respectively. Conditioned medium from 3T3-L1 cells stimulated the growth of NMMG cells by 64 +/- 2%; in contrast, 3T3-L1 CM inhibited the growth of MCF-7 cells by 36 +/- 1%. In parallel with these growth studies, thymidine incorporation increased by 20 +/- 4% in NMMG cells and decreased by 72 +/- 5% in the MCF-7 cells. Moreover, a similar effect was also noted in NCI H630 colon cancer cells, where 3T3-L1 CM produced a 58 +/- 4% decrease in growth and a 82 +/- 6% decrease in thymidine incorporation. Heating the 3T3-L1 CM at 100 degrees C for 30 min destroyed all inhibitory activity. Several known inhibitory growth factors (fibroblast growth factor, 20 ng/ml; interleukin 6, 1000 units/ml; tumor necrosis factor alpha, 15 ng/ml; transforming growth factor beta, 1 ng/ml) were tested for activity in the MCF-7 cells. Tumor necrosis factor alpha and transforming growth factor beta produced a 97% and 67% inhibition of thymidine uptake, respectively, whereas interleukin 6 and fibroblast growth factor had no effect. Neither transforming growth factor beta nor tumor necrosis factor alpha activity was detectable in 3T3-L1 CM using an enzyme-linked immunosorbent assay. High-performance liquid chromatography fractionation of the 3T3-L1 CM revealed that the inhibitory activity eluted at a molecular weight of 67,000; moreover, silver staining of these eluates on a denaturing polyacrylamide gel revealed that M(r) 69,000 peptide was the predominant protein band in the inhibitory fractions. Thus 3T3-L1 CM stimulates the growth of normal breast epithelial cells and inhibits the growth of MCF-7 breast cancer cells. This inhibitory activity appears to be due to a protein secreted by 3T3-L1 preadipocytes.     

Perfluorochemicals as US contrast agents for tumor imaging and hepatosplenography: preliminary clinical results

In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients.     

The nitric oxide pathway in pre-eclampsia: pathophysiological implications

Pre-eclampsia, one of the most significant health problems inhuman pregnancy, complicates 6-7% of all gestations and is theleading cause of fetal growth retardation, infant morbidityand mortality, premature birth and maternal death. Recent researchimplicates free radicals in the pathophysiology of pre-eclampsia.This review covers the biochemistry of nitric oxide (NO) andpossible interactions with other free radicals. Studies in therat show that pregnancy is associated with enhanced productionand responsiveness to NO in both reproductive tissues and bloodvessels. Rats infused with N^G-nitro-L-arginine methyl ester(L-NAME, a NO synthase inhibitor) have been used as an animalmodel of pre-eclampsia, and the effects of steroid hormoneson blood pressure in this model have been tested. Results suggestthat pre-eclampsia may be a state of NO deficiency. However,in humans there seem to be contradictions regarding the involvementof NO in maternal adaptation to pregnancy. It is suggested thatNO may be one of several systems that act in concert to maintaina symbiotic relationship between mother and fetus. However,the input of each system may be genetically determined.     

Surgical sperm retrieval and intracytoplasmic sperm injection as treatment of obstructive azoospermia

Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer.      

Lymphokine-induced phagocytosis in angiocentric immunoproliferative lesions (AIL) and malignant lymphoma arising in AIL

A factor that augmented the phagocytosis of IgG-coated ox red blood cells by the human monocyte/macrophage line U937 was identified in cell culture supernatants from two of two patients with angiocentric peripheral T cell lymphomas, three of three patients with angiocentric immunoproliferative lesions that were not frankly malignant, and one of two patients with T lymphoblastic malignancies. The factor was not present in supernatants derived from 14 nonangiocentric peripheral T cell lymphomas of other histologic types nor in ten cases of B cell lymphoma and two cases of Hodgkin's disease. A similar factor was present in the supernatants of concanavalin A (Con A)-stimulated normal peripheral blood mononuclear cells and in the supernatants of IL-2- dependent T cell lines derived from normal peripheral blood. The factor had an apparent mol wt of greater than 50,000 daltons, was heat labile (100 degrees C for two minutes), and stable at pH 2.0. Its stimulation of phagocytosis was independent of any increase in number of Fc receptors. Thus, this factor is probably not gamma-interferon. This factor may play a pathogenetic role in the hemophagocytic syndromes associated with certain T cell malignancies and immunodeficient states.