Chemosensitizing Effect of Saikosaponin B on B16F10 Melanoma Cells

Cancer cell resistance to chemotherapy is one of the obstacles for better cancer treatment, and inflammatory signaling pathways, such as NF-κB signaling pathway, have been recognized to be involved in such chemoresistance. In this study, we aim to identify a new approach for overcoming cancer chemoresistance by using natural compounds. As a result of screening by using Murine B16F10 melanoma cell line constitutively expressing NF-κB luciferase reporter gene, we identified Saikosaponin B2 as an effective inhibitor for etoposide-induced NF-κB activation in B16F10NFkB cells. Saikosaponin B2 sensitized etoposide-induced cell death in B16F10 melanoma cells through the induction of apoptosis. Along with apoptosis induction, we observed an induction of γ-H2AX expression, which is a molecular signature for DNA damage, upon the combination treatment of etoposide and Saikosaponin B2. Among Saikosaponin family compounds, we found that Saikosaponin B1, but not Saikosaponin A, sensitized etoposide-induced cytotoxicity implicating the structural requirement of Saikosaponin B for such chemosensitization. By testing the combination of Saikosaponin B1 and B2 with 9 clinical anticancer drugs, Saikosaponin B showed a certain preference in the combination with those tested anticancer drugs. Collectively, we conclude Saikosaponin B can be an attractive adjuvant for enhancing the clinical effect of cancer chemotherapy.     

Hybrid approach with laparoscopic wall-inversion surgery and single-incision intragastric surgery for intraluminal gastrointestinal stromal tumor: A case report

Laparoscopic wedge resection (LWR) for intraluminal gastrointestinal stromal tumor (GIST) leads to excessive resection of normal gastric wall. We report a case of GIST around the cardia successfully treated with full-thickness partial resection using a hybrid approach of laparoscopic surgery and single-incision intragastric surgery (SIIGS). A 69-year-old woman had a 5 cm intraluminal GIST at the posterior wall around the cardia. Submucosal injection of glycerin and indigo carmine was performed with transoral endoscopy. Circumferential seromuscular incision followed by placement of seromuscular sutures to invert the lesion into the stomach was performed under laparoscopy. By SIIGS, resection of the inverted mucosa and retrieval of the tumor were completed. A hybrid approach consisting of laparoscopic wall-inversion surgery and SIIGS was useful for intraluminal GIST and may expand the indications for laparoscopic wall-inversion surgery by removing size limitations.     

Recurrent infarctions due to a dome-shaped pannus above the mitral valve prosthesis

This report describes a unique case of a 56-year-old female who suffered from recurrent stroke after double mechanical valve replacement. During the four years after the surgery, she remained in normal sinus rhythm, received adequate anticoagulation therapy, and no apparent left atrial thrombus was detected. She underwent redo surgery to prevent further stroke after fourth instance of cerebral infarction. Intraoperative findings revealed a ‘dome-shaped’ pannus formation covering the sewing ring of the mitral prosthesis circumferentially, probably leading to clot formation and repeated infarctions. She has been stroke free for three years after pannus resection.