A multi-institutional prospective trial in the USA confirms that the 4Kscore accurately identifies men with high-grade prostate cancer.

BACKGROUND: The 4Kscore combines measurement of four kallikreins in blood with clinical information as a measure of the probability of significant (Gleason ≥7) prostate cancer (PCa) before prostate biopsy. OBJECTIVE: To perform the first prospective evaluation of the 4Kscore in predicting Gleason ≥7 PCa in the USA. DESIGN, SETTING, AND PARTICIPANTS: Prospective enrollment of 1012 men scheduled for prostate biopsy, regardless of prostate-specific antigen level or clinical findings, was conducted at 26 US urology centers between October 2013 and April 2014. INTERVENTION: The 4Kscore. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was Gleason ≥7 PCa on prostate biopsy. The area under the receiver operating characteristic curve, risk calibration, and decision curve analysis (DCA) were determined, along with comparisons of probability cutoffs for reducing the number of biopsies and their impact on delaying diagnosis. RESULTS AND LIMITATIONS: Gleason ≥7 PCa was found in 231 (23%) of the 1012 patients. The 4Kscore showed excellent calibration and demonstrated higher discrimination (AUC 0.82) and net benefit compared to a modified Prostate Cancer Prevention Trial Risk Calculator 2.0 model and standard of care (biopsy for all men) according to DCA. A possible reduction of 30-58% in the number biopsies was identified with delayed diagnosis in only 1.3-4.7% of Gleason ≥7 PCa cases, depending on the threshold used for biopsy. Pathological assessment was performed according to the standard of care at each site without centralized review. CONCLUSION: The 4Kscore showed excellent diagnostic performance in detecting significant PCa. It is a useful tool in selecting men who have significant disease and are most likely to benefit from a prostate biopsy from men with no cancer or indolent cancer. PATIENT SUMMARY: The 4Kscore provides each patient with an accurate and personalized measure of the risk of Gleason ≥7 cancer to aid in decision-making regarding the need for prostate biopsy.

Application of AAV2-mediated bFGF gene therapy on survival of ischemic flaps: effects of timing of gene transfer.

Necrosis of surgically transferred flaps is a major problem in reconstructive surgery. We investigated efficacy of a new vector system-adeno-associated viral 2 (AAV2)-mediated bFGF gene transfer to enhance survival of the ischemic flap. Thirty-eight Sprague-Dawley rats were divided into 3 gene therapy groups and 1 nontreated control of 9 or 10 each. 7.5 x 10(10) AAV2-bFGF viral particles were injected to the dorsum of each of the 29 rats; these rats were divided into 3 groups according to the timing of flap elevation. At the time of surgery, 1 week, and 2 weeks after surgery, flaps of 3 x 7 cm were raised. One week after surgery, flap viability was measured. Vascularization and immunohistochemical staining of the bFGF were evaluated of histologic sections. Flap viability was significantly improved by the AAV2-bFGF gene therapy at the time of surgery, and the flaps with the greatest survival area were found in the rats injected with AAV2-bFGF, 2 weeks before surgery. However, flap viability was significantly decreased by the gene therapy 1 week before surgery. Histologically, vascularity was increased in the groups with AAV2-bFGF injection and immunohistochemical staining showed greatly enhanced bFGF expression by gene transfer. The novel approach of AAV2-bFGF gene therapy shows encouraging manifestations in improving survival of flaps when the flaps are prefabricated during or 2 weeks before surgery.

Enhancement of ischemic flap survival by prefabrication with transfer of exogenous PDGF gene.

Treatment of skin flaps by means of gene therapy has been introduced recently as a novel approach to enhance viability of ischemic skin flaps. Transfer of the platelet-derived growth factor (PDGF) to enhance survival of the ischemic skin flap has not been explored. In this study, the authors investigated the effect of the transfer of the PDGF cDNA on survival and vascularity of the ischemic random flap in a rat model, and compared the effects of PDGF gene therapy to those of vascular endothelial growth factor (VEGF) gene therapy. A total of 45 adult Sprague-Dawley rats were randomly divided into four groups. The PDGF gene therapy group (n=10) received the plasmid containing the PDGF cDNA with liposome injected to the dermis of the flap. A saline control group (n=10) received physiologic saline only, and the vector control group (n=10) received liposome plus vector without the PDGF gene segment. In the fourth group (n=15), the VEGF gene was transferred to the flap. Seven days later, a dorsal random flap including the injection area was raised. One rat each from the saline and vector control groups died during the study period and were excluded. The viability of the flap and vascularity within the flaps were assessed 7 days after flap elevation. The PDGF plasmid-treated flaps had significantly greater survival area (60.8+/-7.8 percent) compared with the flaps treated with saline (52.3+/-5.0 percent) and those treated with liposome and vector (50.7+/-5.9 percent). PDGF gene therapy had effects on survival of the flap similar to VEGF gene therapy (57.6+/-5.2 percent, after transfer of VEGF cDNA). Neovascularization with the flap tissues was confirmed by immunohistochemical staining of von Willebrand factor, a marker specific for angiogenesis. The number of newly-formed blood vessels in the transgenic flaps was significantly greater than that of the vessels in the flaps receiving the saline. The findings of this study indicate that transfer of the PDGF cDNA effectively enhances neovascularization of the ischemic skin flap and increases the viability of the flap, and transfer of the PDGF gene is as efficient as transfer of the VEGF gene in improving viability of the skin flap. This study suggests that PDGF gene therapy may be a novel strategy for the treatment of ischemic skin flaps.