Serum-Soluble E-Cadherin Fragments in Lung Cancer

Aims and background

E-cadherin, also known as uvomorulin or cell-CAM 120/80, is one of the subclasses of cadherins, CA2+-dependent cell adhesion molecules. Several recent studies have suggested that loss of E-cadherin may be associated with tumor progression, such as in lung, gastric, hepatocellular, breast and prostatic carcinoma. Assessment of E-cadherin serum levels in lung cancer showed a relation to histologic type.

Methods and study design

Using an enzyme immunoassay, we determined E-cadherin serum levels in 79 patients affected with lung cancer (stage l–IV), 9 patients with breast cancer, 23 patients with different benign diseases, and 20 healthy patients.

Results

At a specificity level of 90%, E-cadherin diagnostic sensitivity was 66.6%, 47.6% and 43.7% in patients affected with squamous cell carcinoma, small cell carcinoma and adenocarcinoma, respectively.

Conclusions

Preliminary results suggest the use of serum E-cadherin as a prospective tumor marker.

Ovca (CA125) Second Generation: Technical Aspects and Serum Levels in Controls, Patients with Liver Disease, Pregnant Women and Patients with Ovarian Disease

An immunoradiometric method of the second generation (IRMA II) is widely used to determine CA125 serum levels. In this study we have evaluated the performance characteristics of a commercially available IRMA CA125 II (Byk-Gulden, Sangtec Diagnostics). The CA125 serum levels were determined in several groups of patients (healthy women, pregnant women, subjects affected by benign and malignant ovarian cancer, patients with liver diseases) with two IRMAs CA125 II (Byk-Gulden, Sangtec Diagnostica and Centocor, Diagnostic Division) and IRMA CA125 I (Byk-Gulden, Sangtec Diagnostica). Our results show a good analytic performance of IRMA CA125 II (Byk-Gulden, Sangtec Diagnostica), a good correlation between IRMAs CA125 II (Byk-Gulden, Sangtec Diagnostica and Centocor, Diagnostic Division), but an unacceptable correlation between IRMAs CA125 II (Byk-Gulden, Sangtec Diagnostica and Centocor, Diagnostic Division) and IRMA CA125 I. A statistically significant difference was observed comparing the values obtained with both IRMAs CA125 II and IRMA CA125 I in the groups of patients. In contrast no statistically significant difference was observed when we compared the values obtained with IRMA CA125 II (Byk-Gulden, Sangtec Diagnostica) and IRMA CA125 II (Centocor, Diagnostic Division). CA125 serum values obtained with the second-generation kits were different from those obtained with the first-generation one; consequently, it is important, especially in the follow-up of cancer patients, that CA125 serum values be obtained with kits of the same generation. Our data seem to suggest the use of second-generation kits to determine CA125 serum levels.

Prevalence of antisperm antibodies by SpermMARtest in subjects undergoing a routine sperm analysis for infertility

To evaluate the prevalence of antisperm antibodies (ASA) attached to the sperm plasma membrane in male partners of infertile couples, the binding of latex particles to spermatozoa was investigated using SpermMARtest, included routinely in semen analysis. A total of 860 men were examined, who were referred consecutively for semen analysis. Of these, 750 men were referred because of infertility (0.6-10 years in duration) whereas 110 were volunteers with a history of previous fertility. Samples were assessed by the SpermMARtest kit using latex particles sensitized with human IgG. Sperm-latex binding was read after 3 min and samples scored as negative, positive or highly positive when < 10, > 10-40, or > 40% binding occurred, respectively. Of the samples 132 (17.3%) were excluded because of azoo- or severe oligo-asthenozoospermia. IgG attached to spermatozoa were detected in nearly 13% of semen samples from the infertile population and in one of 110 fertile men (0.9%). From the infertile group, 6.2% of samples showed > 40% binding, and 6.7% intermediate binding, with an overall ASA prevalence of 12.9% in subjects undergoing semen analysis for infertility.

Defective insulin action in fibroblasts from noninsulin-dependent diabetes mellitus patients with Gln1152 insulin receptor mutation

Insulin action was investigated in cultured skin fibroblasts from two consanguineous patients with a heterozygous point mutation in the insulin receptor kinase (Arg1152-Gln). In spite of normal binding, Gln1152 insulin receptor exhibited 20% increased basal kinase activity, but significantly reduced insulin-dependent autophosphorylation and kinase activity compared to controls from either weight-matched noninsulin-dependent diabetic patients (n = 4) or normal subjects (n = 5). In fibroblasts from the mutant patients, basal alpha-aminoisobutyric acid and 2-deoxyglucose (2-DG) uptake, cytochalasin-B (CB) plasma membrane binding, and glycogen synthase activity were increased to levels similar to those in maximally insulin-stimulated control cells. No insulin stimulation of these metabolic effects was detected in the mutant cells. In spite of the high basal 2-DG uptake and CB binding and the lack of further insulin response, fibroblasts from the mutant patients responded to 12-O-tetradecanoylphorbol-13-acetate with a further 50% increase in 2-DG uptake and CB binding. The magnitude of the effects of insulin and 12-O-tetradecanoylphorbol-13-acetate in control cells were nearly identical. We conclude that the Gln1152 insulin receptor impairs insulin regulation of metabolic responses in patient cells. Its presence in fibroblasts from the mutant patients appears to be accompanied by an increased pool of glucose transporters.

Late gonadal function and autoimmunization in familial testicular torsion

Testicular torsion, one of the most common pediatric urological emergencies, is rarely familial. This study deals with the sixth recorded family with familial testicular torsion and the effects on the spermatogenesis and the appearance of testicular autoantibodies in three affected subjects (two brothers, aged 18 and 15 years, and their father, aged 48 years). The father and one of the brothers, who had peripubertal unilateral testicular torsion, presented normal fertility and oligozoospermia, respectively. The other brother, who had a history of bilateral testicular torsion, did not present pubertal development until he was 18 years old and he needed substitutive testosterone therapy. Sperm autoantibody titer increased only in the two cases with unilateral torsion and remained unmodified at a 5-year follow-up. The results indicate that testicular torsion can cause variable degrees of spermatogenesis impairment and induce development of autoantibodies against spermatozoa and gonadal antigens. The persistence of fertility in the father and the progressive spermatogenesis recovery in one of the affected sons suggest that the damaging effects of these autoantibodies deserve further investigation.

Mutation in a conserved motif next to the insulin receptor key autophosphorylation sites de-regulates kinase activity and impairs insulin action

We have recently reported two non-insulin-dependent diabetic patients exhibiting a heterozygous point mutation (R1152-Q) next to the key tyrosine autophosphorylation sites (Y1146, Y1150, Y1151) of the insulin receptor. In the present study, we demonstrate that the Q1152 mutation alters a previously unrecognized consensus sequence in the insulin receptor family of tyrosine kinases. To define the effect of this alteration on insulin receptor function, the mutant insulin receptor (Q1152) was constructed and overexpressed in NIH-3T3 cells. In spite of normal insulin binding, "in vivo" and "in vitro" autophosphorylation as well as transphosphorylation by the wild-type receptor (WT) were deficient in Q1152 as compared with the transfected WT receptors. Insulin-stimulated kinase activity toward poly(Glu, Tyr) 4:1 and the endogenous substrates p120 and p175 were also impaired in Q1152. However, insulin-independent kinase activity of Q1152 was 2-5-fold higher than that of WT. While insulin stimulated 2-deoxyglucose uptake and glycogen synthase activity in WT-transfected cells with a sensitivity proportional to receptor number, no insulin stimulation was observed in Q1152 cells. Similar to the kinase, insulin-independent glycogen synthase activity and 2-deoxyglucose uptake were 2-fold higher in Q1152 than in either WT or parental cells. We conclude that the Q1152 mutation deregulates insulin receptor kinase and generates insulin insensitivity in cells. Alterations in this highly conserved region of the insulin receptor may contribute to non-insulin dependent diabetes mellitin pathogenesis in humans.