Association Between a Novel Variant of the Human Type 2 Deiodinase Gene Thr92Ala and Insulin Resistance

Thyroid hormone action is an important determinant of energy and glucose metabolism. T4 metabolism is regulated by the deiodinases of which type 2 is expressed in humans in skeletal muscle and brown adipose tissue, where its transcription is stimulated by the β-3 adrenergic pathway. We performed molecular scanning of the human type 2 deiodinase (DIO2) gene and evaluated a novel variant for associations with obesity and insulin resistance, assessing both the main effect and interaction with the Trp64Arg β-3–adrenergic receptor (ADRB3) variant. Molecular scanning of DIO2 in 50 obese Caucasians demonstrated a Thr92Ala variant. Association studies in 972 nondiabetic patients, 135 of whom underwent euglycemic-hyperinsulinemic clamps, showed that subjects with the Thr92Ala variant had lower glucose disposal rate (0.54 ± 0.02 mg · min−1 · kg−1 fat-free mass Ala92 homozygotes vs. 0.44 ± 0.02 Ala92 heterozygotes vs. 0.42 ± 0.04 Thr92 homozygotes, P = 0.0088). Association analysis of the entire group showed significant evidence for a synergistic effect between the Thr92Ala DIO2 and Trp64Arg ADRB3 variants on BMI (both variants 34.3 ± 0.9 kg/m2 vs. neither variant 33.1 ± 0.4 kg/m2, P = 0.04 for interaction). To our knowledge, Thr92Ala is the first description of a missense mutation of DIO2. This variant strongly associates with insulin resistance and, in subjects with the Trp64Arg ADRB3 variant, an increased BMI, suggesting an interaction between these two common gene variants

Finasteride and rofecoxib combination in the treatment of benign prostatic hyperplasia (BPH)

Inflammation is frequently associated with human benign prostatic hyperplasia (BPH) and may concur in the development of urinary obstruction.Cyclooxygenase-2 (COX-2) is an inducible pro-inflammatory enzyme. COX-2 is expressed in prostate tissue, including BPH, and it may stimulate prostate growth by its ability to increase prostaglandin synthesis, promote angiogenesis and inhibit apoptosis. The aim of the study was to analyze whether combination therapy with rofecoxib, a COX-2 inhibitor, and finasteride, an inhibitor of prostatic 5alfa-reductase, offers an advantage compared to finasteride monotherapy in patients with symptomatic BPH

Chromogranin A expression in familial versus sporadic prostate cancer

Objectives. To evaluate whether a significant difference in chromogranin A (CgA) levels exist between patients with familial and sporadic cancer. Methods. The study included 146 patients with clinically localized prostate adenocarcinoma (Stage T2N0M0), who underwent radical prostatectomy between June 1999 and June 2004. Patients were considered to have a positive family history for prostate cancer when the index patient confirmed the diagnosis of prostate cancer in a first-degree relative (brother or father). On the day of surgery, a blood sample for the determination of serum prostate-specific antigen and CgA levels (radioimmunoassay) was obtained from all patients. In a subgroup of 20 patients, CgA mRNA expression was also evaluated by reverse transcriptase-polymerase chain reaction at the prostatic tissue level. Results. A positive familial history was found in 28 (19.2%) of the 146 patients. The mean patient age in the familial group was significantly (P < 0.0001) lower than that in the sporadic group. No significant difference between the familial and sporadic groups was found in terms of prostate-specific antigen level (P = 0.9625) or Gleason score distribution (P = 0.4891). The familial group had significantly (P = 0.0013) lower serum CgA levels (43.3 +/- 12.7 ng/mL, median 39.9) compared with the sporadic group (55.9 +/- 19.4 ng/mL, median 54.1). The familial group also had significantly (P = 0.0432) lower expression of tissue CgA mRNA compared with the sporadic group. Conclusions. The result of significantly lower CgA expression in familial compared with sporadic prostate cancer cases suggests that neuroendocrine activity is not increased in familial cases and also confirms that familial cancer is not a more aggressive disease