Structural analysis of MDM2 RING separates degradation from regulation of p53 transcription activity

MDM2–MDMX complexes bind the p53 tumor-suppressor protein, inhibiting p53's transcriptional activity and targeting p53 for proteasomal degradation. Inhibitors that disrupt binding between p53 and MDM2 efficiently activate a p53 response, but their use in the treatment of cancers that retain wild-type p53 may be limited by on-target toxicities due to p53 activation in normal tissue. Guided by a novel crystal structure of the MDM2–MDMX–E2(UbcH5B)–ubiquitin complex, we designed MDM2 mutants that prevent E2–ubiquitin binding without altering the RING-domain structure. These mutants lack MDM2's E3 activity but retain the ability to limit p53′s transcriptional activity and allow cell proliferation. Cells expressing these mutants respond more quickly to cellular stress than cells expressing wild-type MDM2, but basal p53 control is maintained. Targeting the MDM2 E3-ligase activity could therefore widen the therapeutic window of p53 activation in tumors

Minimally invasive approach to incisional hernia in elective and emergency surgery: a SICE (Italian Society of Endoscopic Surgery and new technologies) and ISHAWS (Italian Society of Hernia and Abdominal Wall Surgery) online survey

Minimally invasive abdominal wall surgery is growing worldwide, with a constant and fast improvement of surgical techniques and surgeons’ confidence in treating both primary and incisional hernias (IH). The Italian Society of Endoscopic Surgery and new technologies (SICE) and the ISHAWS (Italian Society of Hernia and Abdominal Wall Surgery) worked together to investigate state of the art in IH treatment in elective and emergency settings in Italy. An online open survey was designed, and Italian surgeons interested in abdominal wall surgery were invited to fill out a 20-point questionnaire on IH surgical procedures performed in their departments. Surgeons were asked to express their points of view on specific questions about technical and clinical variables in IH treatment. Preferred approach in elective IH surgery was minimally invasive (59.7%). Open surgery was the preferred approach in 40.3% of the responses. In emergency settings, open surgery was the preferred approach (65.4%); however, 34.5% of the involved surgeons declare to prefer the laparoscopic/endoscopic approach. Most respondents opted for conversion to open surgery in case of relevant surgical field contamination, with a non-mesh repair of abdominal wall defects. Among those that used the laparoscopic approach in the emergent setting, the majority (74%) used the size of the defect of 5 cm as a decisional cut-off. The spread of minimally invasive approaches to IH repair in emergency surgery in Italy is gaining relevance. Code-sharing through scientific societies can improve clinical practice in different departments and promote a tailored approach to IH surgery