[BRCA2 Mutation Profile in a Proband with Hereditary Breast and Ovarian Cancer-Two Germline Pathogenic Variants Aligned in the Cis Position].

We report the first Japanese case of hereditary breast and ovarian cancer(HBOC)carrying 2 germline pathogenic variants (GPVs)in the BRCA2 gene. Genetic testing of the BRCA1 and BRCA2 genes was performed in a young woman with HBOC and 2 GPVs were identified in the BRCA2 gene. Since simultaneous GPVs in both parental alleles(ie, trans)in the BRCA2 gene is diagnostic of Fanconi anemia, which is characterized by bone marrow dysfunction and susceptibility to malignancy, we genetically tested her relatives. The same variants were revealed, and both variants were located in the cis position. For patients with multiple GPVs in the BRCA2 gene, we should consider genetic testing of the relatives to confirm whether the variants are located in the cis or trans position under appropriate genetic counseling.

Important risk factors for gallstones after laparoscopic gastrectomy: a retrospective study.

BACKGROUND: The frequency of gallstones is higher in patients who have undergone gastrectomy than in the general population. While there have been some studies of gallstone formation after open gastrectomy, there are few reports of gallstones after laparoscopic gastrectomy (LG). Therefore, this study aimed to evaluate the incidence of gallstones after LG. METHODS: We retrospectively reviewed the records of 184 patients who underwent LG between January 2011 and May 2016 at Saiseikai Utsunomiya Hospital. After gastrectomy, abdominal ultrasonography was generally performed every 6 months for 5 years. Patients who underwent cholecystectomy before LG, underwent simultaneous cholecystectomy, and did not undergo abdominal ultrasonography, with an observation period of < 24 months, were excluded from the study. Finally, 90 patients were analyzed. Laparoscopic cholecystectomy was performed whenever biliary complications occurred. Patient characteristics were compared using the two-tailed Fisher's exact test or Chi-square test. In addition, the risk factors for postoperative gallstones were analyzed using logistic regression analysis. RESULTS: Among the 90 patients included in this study, 60 were men (78%), and the mean age was 65.5 years. Laparoscopic total gastrectomy was performed for 15 patients and laparoscopic distal gastrectomy for 75 patients. D2 lymph node dissection was performed for 8 patients (9%), whereas 68 patients underwent LG with Roux-en-Y reconstruction (76%). Gallstones were detected after LG in 27 of the 90 (30%) patients. Multivariate analysis identified Roux-en-Y reconstruction and male sex as significant risk factors of gallstones after gastrectomy. The incidence of gallstones was significantly higher (53%) in male patients who underwent Roux-en-Y reconstruction. Symptomatic gallstones after laparoscopic cholecystectomy were found in 6 cases (6/27, 22%), and all patients underwent laparoscopic cholecystectomy. CONCLUSION: Roux-en-Y reconstruction and male sex were identified as significant risk factors for gallstones after LG.

Functional Analysis of the Role of Equilibrative Nucleobase Transporter 1 (ENBT1/SLC43A3) in Adenine Transport in HepG2 Cells.

Equilibrative nucleobase transporter 1 (ENBT1/SLC43A3) has recently been identified as a purine-selective nucleobase transporter. Although it is highly expressed in the liver, its role in nucleobase transport has not been confirmed yet in hepatocytes or any relevant cell models. We, therefore, examined its role in adenine transport in the HepG2 cell line as a human hepatocyte model. The uptake of [3H]adenine in HepG2 cells was highly saturable, indicating the involvement of carrier-mediated transport. The carrier-mediated transport component, for which the Michaelis constant was estimated to be 0.268 µM, was sensitive to decynium-22, an ENBT1 inhibitor, with the half maximal inhibitory concentration of 2.59 µM, which was comparable to that of 2.30 µM for [3H]adenine uptake by ENBT1 in its transient transfectant human embryonic kidney 293 cells. Although equilibrative nucleoside transporter 1 (ENT1/SLC29A1) and ENT2/SLC29A2 are also known to be able to transport adenine, [3H]adenine uptake in HepG2 cells was not inhibited by the ENT1/2-specific inhibitor of either dipyridamole or nitrobenzylthioinosine. Finally, [3H]adenine uptake was extensively reduced by silencing of ENBT1 by RNA interference in the hepatocyte model. All these results, taken together, suggest the predominant role of ENBT1 in the uptake of adenine in HepG2 cells.

[A Case of Duodenal Perforation during Bevacizumab Combination Chemotherapy in a Patient with Multiple Lung Metastasis after a Sigmoidectomy].

A 73-year-old man underwent laparoscopic sigmoidectomy for sigmoid colon cancer. Two years after the operation, multiple lung metastasis was diagnosed and chemotherapy with bevacizumab, irinotecan, and TS-1®was started in the patient. However, epigastric pain developed 73 days after the initial course of chemotherapy. Abdominal CT revealed duodenal perforation and generalized peritonitis. Emergency operation with omental patch closure was immediately performed. The patient was discharged 15 days after the emergency operation without any complication. This is an extremely rare case of bevacizu- mab-related duodenal perforation.

Role of Equilibrative Nucleobase Transporter 1/SLC43A3 as a Ganciclovir Transporter in the Induction of Cytotoxic Effect of Ganciclovir in a Suicide Gene Therapy with Herpes Simplex Virus Thymidine Kinase.

A suicide gene therapy using herpes simplex virus thymidine kinase (HSV-TK) with ganciclovir (GCV) has been under development as a tumor-targeted therapy; however, the mechanism of cellular GCV uptake, which is prerequisite in the therapy, has not been clarified. In an attempt to resolve this situation and gain information to optimize HSV-TK/GCV system for cancer therapy, we found that human equilibrative nucleobase transporter 1 (ENBT1) can transport GCV with a Michaelis constant of 2.75 mM in Madin-Darby canine kidney II (MDCKII) cells stably transfected with this transporter. In subsequent experiments using green fluorescent protein (GFP)-tagged ENBT1 (GFP-ENBT1) and HSV-TK, the uptake of GCV (30 µM), which was minimal in MDCKII cells and unchanged by their transfection with HSV-TK alone, was increased extensively by their transfection with GFP-ENBT1, together with HSV-TK. Accordingly, cytotoxicity, which was assessed by the WST-8 cell viability assay after the treatment of those cells with GCV (30 µM) for 72 hours, was induced in those transfected with GFP-ENBT1, together with HSV-TK but not in those transfected with HSV-TK alone. These results suggest that ENBT1 could facilitate GCV uptake and thereby enhance cytotoxicity in HSV-TK/GCV system. We also identified Helacyton gartleri (HeLa) and HepG2 as cancer cell lines that are rich with ENBT1 and A549, HCT-15 and MCF-7 as those poor with ENBT1. Accordingly, the HSV-TK/GCV system was effective in inducing cytotoxicity in the former but not in the latter. Thus, ENBT1 was found to be a GCV transporter that could enhance the performance of HSV-TK/GCV suicide gene therapy.

[A Case of Fournier's Gangrene Caused by Small Intestinal Perforation during Bevacizumab Combination Chemotherapy].

A 51-year-old man underwent abdominoperineal resection for advanced rectal cancer at a hospital. He attended our outpatient clinic 58 months later with pain in the external genitalia, and was diagnosed with local pelvic recurrence and metastasis to the para-aortic lymph node and both adrenal glands. He received a total of 30 Gy of radiation for analgesia; subsequently, chemotherapy(mFOLFOX6 plus bevacizumab)was initiated. However, extreme left buttock and left femoral pain developed after the 6 courses of chemotherapy. Abdominal CT revealed Fournier's gangrene caused by small intestinal perforation. Emergency drainage under spinal anesthesia was immediately performed. Two additional drainage procedures were required thereafter and an ileostomy was constructed. The patient was discharged 100 days after the initial drainage. This is an extremely rare example of a bevacizumab-related small intestinal perforation that developed into Fournier's gan- grene.

Functional identification of SLC43A3 as an equilibrative nucleobase transporter involved in purine salvage in mammals.

The purine salvage pathway plays a major role in the nucleotide production, relying on the supply of nucleobases and nucleosides from extracellular sources. Although specific transporters have been suggested to be involved in facilitating their transport across the plasma membrane in mammals, those which are specifically responsible for utilization of extracellular nucleobases remain unknown. Here we present the molecular and functional characterization of SLC43A3, an orphan transporter belonging to an amino acid transporter family, as a purine-selective nucleobase transporter. SLC43A3 was highly expressed in the liver, where it was localized to the sinusoidal membrane of hepatocytes, and the lung. In addition, SLC43A3 expressed in MDCKII cells mediated the uptake of purine nucleobases such as adenine, guanine, and hypoxanthine without requiring typical driving ions such as Na(+) and H(+), but it did not mediate the uptake of nucleosides. When SLC43A3 was expressed in APRT/HPRT1-deficient A9 cells, adenine uptake was found to be low. However, it was markedly enhanced by the introduction of SLC43A3 with APRT. In HeLa cells, knock-down of SLC43A3 markedly decreased adenine uptake. These data suggest that SLC43A3 is a facilitative and purine-selective nucleobase transporter that mediates the cellular uptake of extracellular purine nucleobases in cooperation with salvage enzymes.

Extensive bowel necrosis related to bevacizumab in metastatic rectal cancer patient: a case report and review of literature.

Recently, bevacizumab has become a key drug for treatment of metastatic colorectal cancer. Molecularly targeted agents such as bevacizumab can cause life-threatening adverse effects, though they are generally considered less toxic than cytotoxic drugs. Here, we review the case of a 76-year-old male rectal cancer patient with liver metastasis who suffered extensive bowel necrosis after administration of 5-fluorouracil-based chemotherapy with bevacizumab, and required a subtotal colectomy and end-ileostomy. Microscopic findings revealed extensive mucosal necrosis in the resected colon specimen and necrosis at the muscularis propria of the descending colon. Pathological findings suggested that the mucosal damage induced by chemotherapy may be exacerbated by treatment with bevacizumab, resulting in extensive necrosis.

Ileosigmoid knot at week 13 of pregnancy: report of a case.

The ileosigmoid knot (ISK) is a rare cause of intestinal obstruction. ISK is a condition in which the ileum wraps around the base of the sigmoid colon and forms a knot, leading to high mortality with rapid progression to bowel gangrene. We herein report a rare case of ISK at week 13 of pregnancy. The ISK was diagnosed by computed tomography, and the patient underwent emergency surgery for acute abdomen. Laparotomy showed segmental gangrenous change in the sigmoid colon, which was twisted around the distal ileal loop. The gangrenous bowel was resected, and primary anastomosis was performed. To our knowledge, the present case involves the first and earliest pregnancy in which a preoperative diagnosis of ISK was made and successful treatment was performed with surgery. A radiologic approach should be undertaken for prompt diagnosis and optimal management, even in early pregnancy.

Pancreatic metastases from renal cell carcinoma: a case report and literature review of the clinical and radiological characteristics.

Metastatic pancreatic cancer is rare, accounting for approximately 2% of all pancreatic malignancies, and most cases arise from renal cell carcinoma. We report the case of a 63-year-old woman, who presented with a pancreatic tumor detected during her annual health examination. She had undergone left nephrectomy 13 years previously for renal cell carcinoma. Computed tomography (CT) revealed two tumors in the head and body of the pancreas, a hypervascular tumor and a hypovascular tumor with an enhanced rim, respectively. She underwent pylorus-preserving pancreaticoduodenectomy, and metastatic pancreatic tumors arising from the kidney with clustered clear cell carcinoma immunohistochemically positive for CD10 were diagnosed. This report presents the different enhancement features of different lesions on CT scans. Because the enhancement features of lesions have been reported to vary according to the size of the metastatic tumor, a knowledge of the history of renal cell carcinoma is crucial for diagnosis.