Despite being one of the most common congenital defects in boys, the etiology of hypospadias remains largely unknown. In this case-referent study, we evaluated a wide spectrum of potential risk factors for hypospadias. Cases were identified from the hospital information system, and referents were recruited through the parents of the cases. Both parents of cases and referents completed written questionnaires that they received through the mail. Logistic regression analyses were used to assess the independent contribution of different factors to the risk of hypospadias. The final database included 583 cases and 251 referents. Hypospadias more often occurred in children whose father had hypospadias (OR=9.7; 95%CI: 1.3-74.0) and in children with a low birth weight (OR=2.3; 95%CI: 1.2-4.2). Indications for elevated risks were found when mothers were DES-daughters (OR=3.5; 95%CI: 0.8-15.6), fathers were subfertile (OR=1.8; 95%CI: 0.7-4.5), the parents had undergone fertility treatment (OR=2.3; 95%CI: 0.9-5.8), and in twin or triplet pregnancies (OR=2.0; 95%CI: 0.8-5.1). Maternal use of iron supplements (OR=2.2; 95%CI: 0.8-6.0), maternal smoking (OR=1.5; 95%CI: 1.0-2.4), paternal prescriptive drug use (OR=2.6; 95%CI: 1.1-6.6), and paternal exposure to pesticides (OR=2.1; 95%CI: 0.6-7.1) during the 3 months immediately prior to conception or in the first trimester of pregnancy also appeared to increase the risk of hypospadias. The associations found in this study support the hypothesis that genetic predisposition, placental insufficiency, and substances that interfere with natural hormones play a role in the etiology of hypospadias.
In vitro cell lines were established from seven biologically distinct in vivo Dunning R3327 rat prostatic tumor sublines. Some of these in vitro cell lines (i.e., G, AT-1, AT-2) retain a low metastatic ability when inoculated back into syngeneic Copenhagen male rats, while others (i.e., AT-3, MAT-LyLu, MAT-Lu) retain a very high metastatic ability. A series of genetic (i.e., DNA content per cell, modal chromosomal number), as well as phenotypic parameters (i.e., morphology, 5 alpha-reductase, androgen receptor, estrogen receptor) were used to validate that the in vitro cell lines retained the major characteristics of the parental in vivo tumor sublines used for their respective establishment. A series of additional characteristics (i.e., morphology, growth rate, saturation density in surface culture, anchorage-dependent and -independent clonogenic potential) were compared between the high vs. the low metastatic in vitro cell lines to determine if a discriminatory parameter could be identified which reproducibly predicted the metastatic abilities of the particular prostatic cancer cell line. While the combination of the in vitro cell lines and their parental in vivo tumor subline will be a valuable tool for developing methods for predicting metastatic ability of prostate cancers, no single parameter yet measured is entirely successful in making this important distinction.
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