Biochemical disease-free survival in patients with a high prostate-specific antigen level (20-100 ng/mL) and clinically localized prostate cancer after radical prostatectomy.

OBJECTIVE: To examine our experience with radical prostatectomy (RP) in patients with a serum prostate-specific antigen (PSA) level of > 20 ng/mL (who are sometimes considered poor candidates for RP) to determine the outcome and possible predictors of a favourable outcome. PATIENTS AND METHODS: We retrospectively reviewed the medical records of 79 patients who underwent RP with an initial PSA of 20-100 ng/mL. Biochemical disease-free survival (BDFS) was assessed using the Kaplan-Meier method and predictors of treatment outcome examined by uni- and multivariate analysis. Patients excluded from the analysis were 11 (14%) whose surgery was aborted after finding cancerous pelvic nodes and who did not undergo RP; four others with normal nodes during RP who had metastatic tumour on permanent sections; and 14 who had follow-up data for < 2 years. RESULTS: The mean (sd) age of the 50 patients in the final study population was 63 (7) years and the mean PSA 37.9 (16.0) ng/mL. The median (range) follow-up was 54 (24-120) months. The BDFS was 60% at 3 years and 48% at 5 years of follow-up. Two patients developed a local recurrence and eight developed metastatic disease. On logistic regression analysis of factors influencing BDFS, only extracapsular extension of disease was predictive of PSA recurrence; no preoperative factor was significant. When time to PSA recurrence was assessed by Cox regression analysis, again only extracapsular extension was predictive, with no preoperative variable a statistically significant predictor. CONCLUSIONS: Patients with a high serum PSA level (20-100 ng/mL) may be appropriate candidates for RP. While the cancer-free survival is not as good as in patients with a lower PSA, a significant percentage of patients achieve BDFS. No preoperative variables were predictive of disease-free survival or time to PSA recurrence.

Chick cartilage fibronectin differs in structure from the fibronectin in limb mesenchyme.

Fibronectin, present in the extracellular matrix of several tissues, is heterogeneous in structure. This heterogeneity is largely due to the alternative splicing of three exons (IIIB, IIIA, and V) during processing of the fibronectin primary transcript. Previously, we determined that the splicing patterns of fibronectin mRNAs change from B+A+ to B+A- during the differentiation of mesenchyme into cartilage (V. D. Bennett, K. M. Pallante, and S. L. Adams, J. Biol. Chem. 266, 5918-5924, 1991). Therefore, the structure of fibronectin at the protein level most likely changes during chondrogenesis as well. In order to characterize the fibronectin protein in chick limb prechondrogenic mesenchyme and cartilage, we generated a polyclonal antibody specific for the region encoded by exon IIIB in the chick fibronectin gene. Immunoblot and immunohistochemistry analyses with this antibody and an antibody specific for the region encoded by exon IIIA indicate that both antibodies react with the fibronectin present in prechondrogenic mesenchyme. In contrast, only the exon IIIB antibody reacts with the fibronectin present in chick cartilage. Quantitative ELISA assays with these antibodies indicate that approximately 96% of the fibronectin in chick embryonic cartilage contains exon IIIB while less than 3% of the fibronectin contains exon IIIA. These results corroborate the structures of the fibronectin isoforms present in prechondrogenic mesenchyme and cartilage that were predicted from our previous characterization of the fibronectin mRNAs in these tissues and indicate that essentially all of the fibronectin in cartilage is synthesized and secreted by cartilage chondrocytes.

The exon encoding the fibronectin type III-9 repeat is constitutively included in the mRNA from chick limb mesenchyme and cartilage.

The fibronectin monomer is comprised of three types of homologous repeating units, the types I, II, and III elements. Each type III repeat is encoded by two exons except for the two type III repeats involved in alternative splicing (IIIB and IIIA) and the type III-9 repeat which are all encoded by one exon. The fact that the type III-9 repeat is the only other type III repeat encoded by one exon has led to speculation that this exon may also be alternatively spliced. However, no evidence exists for alternative splicing of this exon in any tissues examined to date. The recent localization of a cell adhesion synergy site within the type III-9 repeat increases the likelihood of functional ramifications if the exon encoding this repeat is alternatively spliced in specific cells or tissues. We have shown previously that chick cartilage contains an unusual fibronectin mRNA splicing pattern and that the pattern changes during chondrogenesis from B+A+V+ to B+A-V+. In order to completely characterize the fibronectin mRNA in cartilage and other mesenchymal tissues for all possible alternative splicing events, we have determined whether or not the exon encoding the type III-9 repeat is alternatively spliced in these tissues. RNase protection and RT/PCR assays indicate that the fibronectin mRNA in all of these tissues, including cartilage, contains the type III-9 repeat as a constitutively included exon. Thus the exon encoding the type III-9 repeat will serve as a useful control exon for examining the regulation of tissue-specific alternative splicing during chondrogenesis.

Effects of calcitonin on 3',5'-cyclic adenosine monophosphate and calcium second messenger generation and osteoblast function in UMR 106-06 osteoblast-like cells.

The UMR 106-06 rat osteosarcoma osteoblast-like cell line possesses calcitonin (CT) receptors in addition to expressing PTH receptors and a highly osteoblast-like phenotype, and may represent an intermediate developmental stage between early osteoblast precursors and mature osteoblasts. Therefore, we examined the effects of CT and PTH on second messenger generation and osteoblastic function in these cells. In UMR-106-06 cells, 10-1000 nM CT produced a dose-dependent stimulation of intracellular free calcium concentration ([Ca2+]i), which reached a plateau between 2-3 min. This stimulatory effect was abolished in the absence of extracellular Ca2+ ([Ca2+]o) and was mimicked by forskolin and (Bu)2cAMP. One hundred nanomolar CT also produced a slight but significant increase in inositol triphosphate production (13%, P less than 0.05) but did not produce a rapid, transient increase in [Ca2+]i. In contrast, PTH produced a rapid, transient increase in [Ca2+]i, which reached a maximum within 30 sec. This stimulatory effect of PTH on [Ca2+]i signal was dose-dependent and accompanied by a parallel stimulation of inositol triphosphate production. PTH, forskolin, and (Bu)2cAMP all produced a marked dose-related suppression of both DNA and collagen synthesis, which paralleled their stimulatory effects on intracellular cAMP levels. In marked contrast, CT only minimally reduced DNA and collagen synthesis despite producing comparable increases in intracellular cAMP. One hundred nanomolar CT also stimulated alkaline phosphatase specific activity by 33% (P less than 0.05). Thus, CT stimulates cAMP, [Ca2+]i, and inositol phosphate second messengers in UMR 106-06 cells. However, in contrast to other agents which elevate intracellular cAMP levels, CT does not suppress DNA synthesis. These results suggest that the linkage of CT receptor second messengers to effects on cell function differ from those of PTH and/or that CT may produce additional second messenger(s) which antagonize the antiproliferative effect of increased cAMP levels in UMR-106-06 cells.

Individual variability in concentrations of urinary sulindac sulfide.

Among 70 patients with arthritis who were receiving satisfactory maintenance therapy with sulindac (300 to 400 mg daily), 64% had no detectable sulindac sulfide (active metabolite) in one to four random urine specimens. However, 36% had 1.0 to 7.8 (mean, 2.2 +/- 1.4) micrograms/ml sulindac sulfide in urine, similar to the therapeutically effective concentrations found in 24 concurrent plasma specimens (1.4 to 9.0 micrograms/ml). Ten patients had sulindac sulfide in only one or two of two to four urine specimens. Thus, 36% of the patients had pharmacodynamically significant concentrations of sulindac sulfide in urine, presumably capable of suppressing the cyclooxygenase pathway responsible for prostaglandin synthesis in the kidney and elsewhere. The findings suggest individual variability in the capacity for renal oxidation of sulindac sulfide to inactive metabolites, perhaps related to genetic or environmental factors or both. These findings may help to explain conflicting reports on the effects of sulindac on urinary prostaglandins and renal function.

Glucocorticoid-induced osteoporosis: a cross-sectional study.

We studied 70 patients (48 women and 22 men) with either rheumatic disease (n = 25) or lung disease (n = 45) who had been treated with glucocorticoids for at least 6 months (mean cumulative dose, 24.2 +/- 27.1 g of prednisone; mean current dose, 11.0 +/- 8.6 mg/d, mean duration of therapy, 8.1 years. We measured bone mineral density (BMD) of the hip (femoral neck) and spine (L2-L4) using dual-photon absorptiometry and BMD of the distal one third radius using single-photon absorptiometry. Compared with age-matched controls, the study population had decreased BMD of the spine (87.0%), hip (87.2%), and radius (90.6%). Current dose, cumulative dose, and duration of therapy were not correlated with BMD in the spine or hip in the total study population. The most significant correlations with low bone mass at the hip and spine were short height and low weight. There was a high incidence of hypercalciuria (30%) as compared with an age- and sex-matched control group (6.4%). Glucocorticoids are known to decrease vertebral and radial bone density. We conclude that glucocorticoids also decrease hip bone density as measured at the femoral neck. The high incidence of hypercalciuria may have implications for therapy of glucocorticoid-induced osteoporosis.