Development of Low-Molecular-Weight Compounds Targeting the Cancer-Associated KLF5 Transcription Factor.

Krüppel-like factor 5 (KLF5) is a potential target for anticancer drugs. However, as an intrinsically disordered protein (IDP) whose tertiary structure cannot be solved, innovative strategies are needed. We focused on its hydrophobic α-helix structure, defined as an induced helical motif (IHM), which is a possible interface for protein-protein interaction. Using mathematical analyses predicting the α-helix's structure and hydrophobicity, a 4-amino-acid site (V-A-I-F) was identified as an IHM. Low-molecular-weight compounds that mimic the main chain conformation of the α-helix with the four side chains of V-A-I-F were synthesized using bicyclic pyrazinooxadiazine-4,7-dione. These compounds selectively suppressed the proliferation and survival of cancer cells but not noncancer cells and decreased the protein but not mRNA levels of KLF5 in addition to reducing proteins of Wnt signaling. The compounds further suppressed transplanted colorectal cancer cells in vivo without side effects. Our approach appears promising for developing drugs against key IDPs.

Predictive factor for intraoperative tumor rupture of Wilms tumor.

PURPOSE: For Wilms tumor, intraoperative tumor rupture with wide tumor spillage during surgical manipulation raises the classification to stage 3. Then, postoperative chemotherapy must be more intensive, and abdominal radiotherapy is added. Therefore, intraoperative tumor rupture should be avoided if possible. However, predictive factors for intraoperative tumor rupture have not been sufficiently described. Here we examined the risk factors for intraoperative tumor rupture. METHODS: Patients with Wilms tumor who underwent treatment according to the National Wilms Tumor Study or the Japanese Wilms Tumor Study protocol at our institution were reviewed retrospectively. Collected cases were categorized into two groups: the ruptured group and the non-ruptured group. Risk factors for intraoperative tumor rupture, including the ratio of the tumor area to the abdominal area in a preoperative single horizontal computed tomography slice (T/A ratio), were investigated in both groups. RESULTS: The two groups were not different in age, body weight, tumor laterality, sex, or histological distribution. The T/A ratio in the ruptured group was significantly higher than that in the non-ruptured group. Receiver operating characteristic curve analysis identified a discriminative value for a T/A ratio >0.5. CONCLUSION: The T/A ratio can be a predictive factor for intraoperative tumor rupture of Wilms tumor.

[Appropriate Biliary Drainage Methods for Unresectable Cholangiocarcinomas].

We investigated the efficacy of different biliary drainage methods for the treatment of unresectable cholangiocarcinomas. We performed a retrospective study of 28 patients with unresectable cholangiocarcinomas who underwent biliary drainage at our hospital between January 2008 and June 2014 to compare the incidence of post-drainage stent dysfunction (SD) and reintervention (RI) for SD according to primary drainage method, lesion site, and complication status (the presence or absence of cholangitis). The duration of stent patency was compared between the different stent types. No significant differences in the incidence of SD and RI were found according to primary drainage methods, lesion site, or the presence or absence of cholangitis. The mean durations of stent patency for plastic and metal stents were 2.7 months and 7.4 months, respectively, suggesting that metal stents should be selected when the estimated prognosis is ≥2 months. Furthermore, metal stent placement, rather than the additional placement of plastic stents, should be considered a feasible option in cases of SD.

Surgical reconstruction and endoscopic pancreatic stent for traumatic pancreatic duct disruption.

Nonoperative management is acceptable treatment for minor pancreatic injuries. However, management of major pancreatic duct injury in children remains controversial. We present our experience in treating isolated pancreatic duct injury. We describe the cases of three male patients treated for complete pancreatic duct disruption in the past 5 years at our institution. We performed pancreatic duct repair to avoid distal pancreatectomy and to maintain normal pancreatic function. All patients underwent enhanced computed tomography and endoscopic retrograde cholangiopancreatography in the early period. The injuries were classified as grade III according to the American Association for the Surgery of Trauma classification. In two cases, we performed end-to-end anastomosis of the pancreatic duct during the delayed period. In the third case, we placed a stent across the disruption to the distal pancreatic duct. The patients' postoperative courses were uneventful, and the average hospitalization was 25.6 days after the procedure. At a median follow-up of 36 months (range 14-54 months), all patients remain asymptomatic, with normal pancreatic function, but with persistent distal pancreatic duct dilatation. We suggest that distal pancreatectomy should not be routinely performed in patients with isolated pancreatic duct injury.

Balloon tracheoplasty as initial treatment for neonates with symptomatic congenital tracheal stenosis.

Neonates with congenital tracheal stenosis (CTS) sometimes develop respiratory distress and may be difficult to intubate. We used balloon tracheoplasty with a rigid bronchoscope for emergency airway management in neonates with symptomatic CTS. Herein, we describe the balloon tracheoplasty procedure and the early outcomes following its use as the initial treatment of neonatal symptomatic CTS. We performed a retrospective analysis of five neonates with CTS who were initially treated with balloon tracheoplasty at our institution from January 2010 to December 2013. Five patients with a mean birthweight of 2,117 g were treated during the study period. Of these, four developed respiratory distress after birth, and all patients had difficult intubations. In all five patients, definitive diagnosis of CTS was made by rigid bronchoscopy and 3-dimensional reconstruction scan. A total of nine balloon dilatations were performed in five patients. Following balloon tracheoplasty, two patients were extubated, one was extubated after resection and end-to-end anastomosis following initial balloon dilatation, and one remained hospitalized with tracheostomy for tracheomalacia. The remaining patient died from tracheal bleeding associated with congenital heart disease. Although our sample size was small, balloon tracheoplasty is a potentially effective initial treatment for selected cases with neonatal symptomatic CTS.