Short-term outcomes of the prospective multicentre 'Prostate Cancer Research International: Active Surveillance' study

OBJECTIVE To evaluate the short-term outcomes of the prospective international Prostate Cancer Research International: Active Surveillance ('PRIAS') study (Dutch Trial Register NTR1718), as active surveillance (AS) for early prostate cancer might provide a partial solution to the current overtreatment dilemma in this disease. PATIENTS AND METHODS The first 500 (of > 950) participants with asymptomatic T1c/T2 prostate cancer, with a prostate-specific antigen (PSA) level of 6 or more than two positive biopsy cores. There was a relatively unfavourable PSA doubling time of 0-10 years in 53% (102/194) and 62% (33/53) of men with favourable and unfavourable re-biopsy results, respectively. After RP, four of 24 (17%) men had T3 disease and 12 (50%) had a Gleason score of > 6. CONCLUSION AS seems feasible, but mortality outcomes are unknown. A strict follow-up protocol including standard 1-year repeat biopsies resulted in a quarter of men stopping AS after 2 years

The mechanism of patellamide macrocyclization revealed by the characterization of the PatG macrocyclase domain

Peptide macrocycles are found in many biologically active natural products. Their versatility, resistance to proteolysis and ability to traverse membranes has made them desirable molecules. Although technologies exist to synthesize such compounds, the full extent of diversity found among natural macrocycles has yet to be achieved synthetically. Cyanobactins are ribosomal peptide macrocycles encompassing an extraordinarily diverse range of ring sizes, amino acids and chemical modifications. We report the structure, biochemical characterization and initial engineering of the PatG macrocyclase domain of Prochloron sp. from the patellamide pathway that catalyzes the macrocyclization of linear peptides. The enzyme contains insertions in the subtilisin fold to allow it to recognize a three-residue signature, bind substrate in a preorganized and unusual conformation, shield an acyl-enzyme intermediate from water and catalyze peptide bond formation. The ability to macrocyclize a broad range of nonactivated substrates has wide biotechnology applications