Molecular Dynamics Study of Conformational Changes of Tankyrase 2 Binding Subsites upon Ligand Binding.

The interactions between proteins and ligands are involved in various biological functions. While experimental structures provide key static structural information of ligand-unbound and ligand-bound proteins, dynamic information is often insufficient for understanding the detailed mechanism of protein-ligand binding. Here, we studied the conformational changes of the tankyrase 2 binding pocket upon ligand binding using molecular dynamics simulations of the ligand-unbound and ligand-bound proteins. The ligand-binding pocket has two subsites: the nicotinamide and adenosine subsite. Comparative analysis of these molecular dynamics trajectories revealed that the conformational change of the ligand-binding pocket was characterized by four distinct conformations of the ligand-binding pocket. Two of the four conformations were observed only in molecular dynamics simulations. We found that the pocket conformational change on ligand binding was based on the connection between the nicotinamide and adenosine subsites that are located adjacently in the pocket. From the analysis, we proposed the protein-ligand binding mechanism of tankyrase 2. Finally, we discussed the computational prediction of the ligand binding pose using the tankyrase 2 structures obtained from the molecular dynamics simulations.

[An Elderly Colon Cancer Patient with Multiple Liver Metastases Who Was Successfully Treated Using mFOLFOX6 and sLV5FU2 Chemotherapy - A Case Report].

Curative treatment for unresectable colon cancer is difficult, and therefore, chemotherapy is often administered in an attempt to improve the prognosis. However, the safety andfeasibility of chemotherapy for elderly patients over 80-years-old have not yet been clarified. We report an elderly colon cancer patient with multiple liver metastases who was successfully treatedwith mFOLFOX6 andsLV5 FU2 chemotherapy. The patient was an 83-year-old-man who was referredto our hospital. After performing sigmoidectomy, we administered mFOLFOX6 chemotherapy. After 5 courses, the regimen was changed to sLV5FU2 owing to grade 3 neuropathy. Liver metastases disappearedanda complete response was obtained1 year after chemotherapy administration. Twenty-four courses of sLV5FU2 chemotherapy had been safely performed. Although grade 1 neutropenia developed, no other adverse event was observed. Currently, the patient is alive without recurrence. Chemotherapy for elderly patients is both feasible and safe.

[A Case of Liver Metastasis of Ampullary Carcinoma That Developed Postoperatively That Was Effectively Treated with Gemcitabine plus Cisplatin].

A 75-year-oldman presenting with obstructive jaundice was referredto our hospital. Basedon a diagnosis of carcinoma of the ampulla of Vater, we performed pancreatoduodenectomy. Postoperative histopathological examination revealed a welldifferentiated papillotubular adenocarcinoma, T3, N0, M0, Stage III . Six months after surgery, an isolatedliver metastasis in S6 was identifiedon CT scan andMRI; therefore, we administeredgemcitabine plus cisplatin chemotherapy. After 6 courses of this regimen, a clinical complete response(CR)was obtained. After 12 courses, the clinical CR continued; however, grade 3 lower-extremity peripheral neuropathy appeared. Therefore, gemcitabine monotherapy was administered as second line chemotherapy. However, multiple liver metastases appearedandthe patient passedaway owing to exacerbation of the disease 2 years after initiating chemotherapy. Although recurrent ampullary carcinoma is difficult to treat, our patient had a long-term survival. Here we report the details of our case and review the relevant literature.

[A Case of Gastric Carcinoid Associated with Hypergastrinemia Treated with LATG].

A 67-year-old man had a gastric polyp diagnosed on screening. Atrophic changes in the upper gastric mucosa were seen on upper gastrointestinal endoscopy. In addition, endoscopy revealed in the middle area of the stomach wall a 10 mm polyp that was diagnosed as a carcinoid tumor through biopsy. Blood serum gastrin was elevated at 2,800 pg/mL.We diagnosed a Rindi Type 1 gastric carcinoid. The patient was planned to be treated with surgical laparoscopy assisted distal gastrectomy (LADG); however, the procedure was changed to intraoperative laparoscopy assisted total gastrectomy (LATG). Chromogranin-positive tumor pathological findings in the mucous membrane submucosa and in the muscularis mucosae endocrine cell micronest (ECM) were widespread. There was no obvious vascular invasion. After the surgery, the serum gastrin level normalized and the patient remains alive.

[A Case of Abdominal Wall Hernia Rupture during Bevacizumab Treatment].

A 78 -year-old man with rectal cancer underwent abdominoperineal resection of the rectum. In the postoperative period, the patient experienced wound infection, leading to an abdominal wall hernia. Two years following surgery, a rise in the serum CEA level was seen. A metastatic tumor was detected in the right lung on chest CT. VATS right lung inferior lobe segmental resection was performed. After lobectomy, the serum CEA level continued to increase. Another metastatic tumor was detected in the right lung on chest CT. Chemotherapy with capecitabine, oxaliplatin, and bevacizumab was commenced. The erosive part of the abdominal wall scar hernia extended during the nine weeks of chemotherapy. The chemotherapy was then discontinued. In the follow-up CT scan, a right pleural recurrence, local recurrence in the pelvis, and a liver metastasis were detected. Chemotherapy was re-introduced 3 years after surgery. The erosive part of the abdominal wall hernia again began to spread with chemotherapy recommencement. Four months after restarting chemotherapy, the hernia ruptured, with a loop of the small intestine protruding out of it. The patient covered this with a sheet of vinyl and was taken by the ambulance to our hospital. The erosive part of the abdominal wall hernia had split by 10 cm, and a loop of the small intestine was protruding. As ischemia of the small intestine was not observed, we replaced it into the abdominal cavity, and performed a temporary suture repair of the hernia sac. Following this, bevacizumab was discontinued, and the erosive part reduced. We performed a radical operation for abdominal wall scar hernia repair 11 weeks after the discontinuation of bevacizumab.

[Super-Elderly Patient with Recurrent Rectal Cancer with Liver Metastases Effectively Treated with Capecitabine plus Bevacizumab Chemotherapy--Report of a Case].

The safety and feasibility of chemotherapy for super-elderly patients (over 85 years old) has not been clarified yet. We report an extremely aged patient with recurrent rectal cancer that was successfully treated with capecitabine plus bevacizumab chemotherapy. An 85-year-old-woman underwent a Hartmann procedure for rectal cancer. Nine months after surgery, tumor markers were elevated. CT and MRI revealed liver metastases in S5 and S7. We administered capecitabine plus bevacizumab chemotherapy. Tumor makers were normalized after 2 courses, and the liver metastases disappeared after 6 courses. Although Grade 1 hypertension developed, no other adverse event occurred. Chemotherapy has been safely performed for 20 courses. The patient's PS score has been maintained at 0, and she has been under treatment as an outpatient. We suggest that capecitabine plus bevacizumab chemotherapy is an effective regimen for extremely aged patients with recurrent colorectal cancer.

[Clinical outcome of 13 patients with perforated colorectal cancer].

We investigated the clinicopathological findings of 13 patients with perforated colorectal cancer. In 6 patients, the primary region affected by the cancer was the sigmoid or rectosigmoid colon, and 9 out of 13 patients had perforations at the location of the tumor itself. The Hartmann operation was performed in 5 patients, and D2 or D3 lymph node dissection was performed in 6 patients. The final stages of the 13 patients were as follows: 1 patient with stage II cancer, 5 patients with stage III cancer, and 7 patients with stage IV cancer. Postoperative death occurred in 1 patient. Five out of 7 patients with curative operations had recurrences; 2 patients had peritoneal disseminations, 2 patients had lung metastases, and 1 patient had paraaortic lymph node metastases. Even if patients underwent a curative operation, a high frequency of recurrence, especially of peritoneal dissemination, was observed. Therefore, we conclude that a careful follow-up is required.

[A case of advanced rectal cancer with irinotecan (CPT-11)-induced delayed emesis].

A 64 -year-old woman was referred to our hospital with a diagnosis of advanced rectal cancer with metastases to the left supraclavicular lymph nodes and paraaortic lymph nodes. Alow anterior resection was performed because of the symptoms of ileus. Subsequently, chemotherapy consisting of XELOX with bevacizumab was initiated as the first-line regimen, over 6 courses. Asecond -line regimen of FOLFIRI with bevacizumab was selected due to multiple lung metastases and the progression to both left supraclavicular and paraaortic lymph nodes. During the first 3 courses, the patient had no harmful side effects. Although the patient received adequate prophylactic antiemetic therapy and supportive treatment, grade 4 delayed emesis induced by irinotecan (CPT-11) occurred at 7 days after the fourth course of FOLFIRI chemotherapy. The patient was given total parenteral nutrition, after which she recovered substantially from the emesis. Delayed emesis is occasionally seen with irinotecan therapy and can be efficiently managed with adequate prophylactic antiemetic therapy. However, delayed emesis occurring one week after administration is rarely observed. Delayed emesis and subsequent therapy affect the quality of life (QOL) of the patient and subsequent therapy therefore, adequate attention and prompt management are required for delayed emesis.

[A case of advanced HER2- positive gastric cancer with a partial response to molecular targeted chemotherapy (S-1+CDDP+Trastuzumab)].

A 61-year-old man was referred to our hospital because of gastric pain and weight loss.Upper gastrointestinal endoscopy revealed a superficial depressed (Type 3) tumor with pyloric stenosis.The tumor was diagnosed as tubular adenocarcinoma by pathological examination.Abdominal computed tomography showed enlarged paraaortic and No. 8a lymph nodes.The patient underwent distal gastrectomy (D0)and Roux-en-Y reconstruction.After surgery, chemotherapy combined with molecular targeted therapy (S-1+cisplatin[CDDP]+trastuzumab), based on overexpression of the HER2 protein in the primary tumor as assessed by immunostaining, was administered.After the molecular targeted chemotherapy, the carcinoembryonic antigen (CEA )levels decreased to the normal range and the enlarged lymph nodes were remarkably decreased in size. The patient is currently alive without progressive disease.

The effects of chemotherapy on primary small bowel cancer: A retrospective multicenter observational study in Japan.

Small bowel cancer is relatively rare among gastrointestinal tract cancers, including esophageal, gastric and colorectal cancers. The majority of cases of small bowel cancer are diagnosed at an advanced stage, resulting in poor outcomes. The clinical effects of chemotherapy on small bowel cancer have been investigated in a limited number of studies from Europe and the USA. However, they have not yet been fully investigated in Asian countries, including Japan. This retrospective multicenter observational study was designed to investigate the efficacy of chemotherapy on small bowel cancer. A questionnaire survey was conducted in 28 hospitals affiliated with the Osaka University Hospital. We retrospectively reviewed the medical records of 61 patients with small bowel cancer (32 patients who were unable to undergo curative resection or had unresectable distant metastases and 29 who underwent curative resection), treated between 1996 and 2009, to evaluate the outcomes and the efficacy of chemotherapy. There was no significant difference in the overall survival between the patients undergoing curative resection with postoperative adjuvant chemotherapy and those without postoperative adjuvant chemotherapy. In patients with non-curative resection or unresectable distant metastases, the response rate to chemotherapy was 31.6% and the overall survival was significantly higher compared to that without chemotherapy (P=0.008). The study results suggested that chemotherapy is effective for Japanese patients with small bowel cancer who cannot undergo curative resection or have unresectable distant metastases.

Identification of a key element for hydrogen-bonding patterns between protein kinases and their inhibitors.

In this article, we report crystal structures for inhibitor-kinase complexes in which the inhibitor has different binding orientations and hydrogen-bonding patterns with extracellular-signal regulated kinase 2 and insulin receptor tyrosine kinase. Our crystallographic studies, and sequence and structural analyses of 532 coordinates of kinases held in the Protein Data Bank, suggest that the length of the "specificity linker" described here is a key structural element of the hydrogen-bonding patterns between protein kinases and their inhibitors.

Sendai virus-mediated gene delivery into hepatocytes via isolated hepatic perfusion.

The recombinant Sendai virus vector is a promising tool for human gene therapy, capable of inducing high-level expression of therapeutic genes in tissue cells in situ. The target tissues include airway epithelium, blood vessels, skeletal muscle, retina and the central nervous system, but application to hepatic tissues has not yet been achieved, because direct intraportal injection of the vector is not feasible. We report an efficient and harmless procedure of gene delivery by recombinant Sendai virus into rat parenchymal hepatocytes, based on isolated hepatic perfusion with controlled inflow. Critical parameters for successful hepatic gene delivery are a brief preperfusion period (25 degrees C, 5 min); appropriate vector concentration in the perfusate (10(7) pfu/ml); moderate portal vein pressure (12 mmHg) and a brief hyperthermic postperfusion period (42 degrees C, 5 min). Under these optimized conditions, marker genes were expressed in most parenchymal hepatocytes without significant damage to hepatic tissues. Furthermore, expression of the marker genes was undetectable in nonhepatic tissues, including the gonads, indicating that this approach strictly targets hepatic tissues and thus offers good clinical potential for human gene therapy.

A case of noninvasive ductal carcinoma arising in malignant phyllodes tumor.

We report on an exceedingly rare case of noninvasive ductal carcinoma arising in malignant phyllodes tumor of the breast. The patient was a 75-year-old woman who presented with a chief complaint of an indolent tumor mass of the left breast. Papillotubular carcinoma was diagnosed by aspiration cytology, and mastectomy with preservation of the pectoral muscle was subsequently performed (Bt+Ax+Ic, R2). Histopathological examination showed proliferation of monotonous, uniform tumor cells in a cribriform pattern amid atypical and spindle-shaped cells. Neither stromal invasion of the epithelial tumor cells nor clear transition between epithelial tumor cells and non-epithelial tumor cells was seen. Immunohistochemical staining revealed that the epithelial component was positive for antibodies such as CEA, EMA and keratin, while the non-epithelial component was negative for the same antibodies. Malignant phyllodes tumor with a noninvasive ductal carcinoma was diagnosed rather than true carcinosarcoma of the breast. No metastasis was detected in the axillary lymph nodes, and the patient was classified as stage II A (T2N0M0). Although neither chemoendocrine therapy nor irradiation was employed postoperatively, no recurrence was observed two years and two months after the surgery. There is little consensus on the treatment or prognosis of the disease. Careful observation of the present case is therefore important.

[A case of gastric adenosquamous carcinoma with abdominal paraaortic lymph node metastases successfully treated by TS-1 plus CDDP neoadjuvant chemotherapy].

A 62-year-old woman was admitted for anemia. An endoscopic examination revealed type 2 cancer from the upper body of the stomach to the antrum, and abdominal CT scan demonstrated enlarged abdominal paraaortic lymph nodes. The preoperative diagnosis was cStage IV gastric cancer (cT 3, cN 3, cH 0, cP 0, cM 0). Since a curative operation was deemed impossible, we conducted neoadjuvant chemotherapy using TS-1 plus cisplatin (CDDP) for downstaging. TS-1( 100 mg/day) was orally administered for 3 weeks,and CDDP (60 mg/m2) was given intravenously on day 8. Appetite loss of grade 3 and erythropenia of grade 1 were observed. After two courses of chemotherapy the primary lesion and the paraaortic lymph nodes were significantly reduced in size. She was judged as clinical PR, followed by distal gastrectomy and lymph node dissection, resulting in curability A. Histopathologically, the tumor was diagnosed as adenosquamous carcinoma of the stomach with lymph node metastasis at only No.3. This case suggests that neoadjuvant chemotherapy using TS-1 plus CDDP is effective for advanced gastric adenosquamous carcinoma with massive lymph node metastases.

[A case of drug-induced interstitial pneumonitis after gemcitabine treatment for advanced pancreatic cancer].

A 54-year-old woman with advanced pancreatic cancer with peritoneal dissemination was given gemcitabine on days 1,8 and 15, and this was repeated on day 29 at a dose of 1,000-1, 150 mg/m2. After 5 courses,the total infusion was 20,900 mg. Thirteen days after the last infusion, she suffered from sudden dyspnea, and soon went into respiratory failure of WHO grade 4 with severe hypoxemia. Chest radiograph and CT showed interstitial infiltrates of bilateral lower lung. She was diagnosed with drug-induced interstitial pneumonitis due to gemcitabine. Corticosteroid therapy consisting of methylprednisolone (1 g/day) for three days followed by prednisolone(50 mg/day) was significantly effective in treatment of respiratory failure. Her symptoms were improved clinically within one week after the onset,and the interstitial shadows in the lungs had almost disappeared radiographically within three weeks after the onset. Respiratory symptoms did not appear again,but the patient died of progression of peritoneal dissemination of pancreatic cancer 73 days after the onset of the interstitial pneumonitis. Gemcitabine- induced interstitial pneumonitis is very rare, but could become a serious complication in long-term gemcitabine treatment.

Pathological complete response to trastuzumab and paclitaxel in a patient with inflammatory local recurrence following breast conserving surgery.

We encountered a case of inflammatory local recurrence of breast cancer after breast conserving surgery which attained pathological CR after combination therapy with trastuzumab and paclitaxel. The patient was a 49-year-old premenopausal woman whose left breast cancer(T2N0M0)was treated by breast conserving surgery (Bp+Ax). The pathological diagnosis was scirrhous carcinoma, g, ly1, v0, t2, n0, ER (-), PgR (+) and stage I A. Postoperatively, the residual breast was treated by 50 Gy irradiation followed by hormone therapy(Tamoxifen citrate+LH-RH analog). At 26 months after the surgery, local recurrence developed as inflammatory breast cancer. As the recurrent tumor was confirmed to be HER2-positve (3+ by IHC), combination therapy with trastuzumab and paclitaxel was started. After the 6 courses of pharmacotherapy were completed, she was judged to have clinical CR, and subsequently underwent total breast excision(Bt)and skin grafting. No visible cancer cell was observed in the resected specimens, pathological CR was diagnosed. Postoperatively, the patient is receiving trastuzumab alone every other week, and at present 10 months after the second operation, the patient is in CR status and is visiting the outpatient clinic. No severe side effects (over grade 3) from this therapy have been observed. It is suggested that combination therapy with trastuzumab and paclitaxel for inflammatory local recurrence after breast conserving surgery is a treatment of choice.

[A case of peritoneal dissemination of gastric cancer successfully treated by irinotecan combined with cisplatin].

We report a case of a 59-year-old man with advanced gastric cancer. Distal gastrectomy with lymph node dissection (D1) was performed. Pathological staging was IV (T3N1CY1), and the operation resulted in curability C. The serum CA19-9 level before the operation was 201 U/ml, and it did not normalize 3 months after the operation. Postoperative chemotherapy (TS-1, 100 mg/day) was performed. Because the tumor markers such as CEA and CA19-9 level elevated 5 months after the operation, triweekly docetaxel therapy and TS-1 administration (days 1-14) were performed. We disbontinued this therapy after 2 courses due to adverse reactions, such as leukopenia (grade 4) and liver dysfunction (grade 2). Peritoneal dissemination was diagnosed by the appearance of ascites and thickness of the peritoneum 11 months after the operation. So the patient was treated with a biweekly combination chemotherapy of irinotecan (CPT-11 60 mg/m2) and cisplatin (CDDP 30 mg/m2). Eight courses of this therapy induced partial remission and normalization of the serum CEA level. No major adverse reaction to this therapy was observed. The partial remission and good patient's QOL were achieved during follow-up 7 months after the administration of CPT-11 plus CDDP. This case suggests that patients with recurrent peritoneal dissemination of gastric cancer could benefit from CPT-11 with CDDP combination therapy as a second-line or third-line treatment.

[A case of recurrent gastric cancer tolerant to TS-1 therapy successfully treated by TS-1 combined with docetaxel].

We report a case of a 58-year-old man with advanced gastric cancer producing sialyl-Tn antigen (STN). Total gastrectomy with distal pancreatectomy and splenectomy was performed. Pathological staging was IV (T 3 N 2 CY1), and most of the cancer cells were strongly positive for anti-STN antibody on immunohistochemical stainings. Serum STN level before the operation was 2,500 U/ml, and the value significantly decreased to the normal range (< 45 U/ml) 2 months after the operation. Low-dose FP (5-FU+CDDP) followed by TS-1 alone (80 mg/day) had been performed as adjuvant chemotherapy. Jaundice appeared and the serum STN level increased again 22 months after the operation. He was diagnosed with a recurrence in the hilar lymph node of the liver. After implantation of expandable stent in the common bile duct, triweekly docetaxel therapy with TS-1 administration (day 1-14) has been performed. Three courses of this therapy have induced a complete response of the recurrent lymph node and the normalization of the serum STN value. No major adverse reaction to this therapy was observed. A complete response and good patient QOL have been achieved during follow-up 8 months after the administration of TS-1 with docetaxel. This case suggests that patients with recurrent gastric cancer who have undergone prior therapy with TS-1 alone could benefit from TS-1 with docetaxel therapy as a second line.

YM-254890 analogues, novel cyclic depsipeptides with Galpha(q/11) inhibitory activity from Chromobacterium sp. QS3666.

The structure elucidation and biological activity of novel YM-254890 (1) analogues and semi-synthetic derivatives are described. Three natural analogues, YM-254891 (2), YM-254892 (3), and YM-280193 (4), were isolated from the fermentation broth of Chromobacterium sp. QS3666, and two hydrogenated derivatives, YM-385780 (5) and YM-385781 (6), were synthesized from YM-254890. Their structures were determined by one- and two-dimensional NMR studies and mass spectrometry. Among these compounds, two natural analogues 2-3 which possessed acyl groups at beta-HyLeu-1 and one derivative 6 whose conformation was similar to that of 1 showed comparable Galpha(q/11) inhibitory activity to that of 1. This indicates that the acyl beta-HyLeu residue plays an important role in activity and also that the alpha,beta-unsaturated carbonyl group of the N-MeDha residue is not critical to activity. The other hydrogenated derivative 5 had significantly less activity, which could be attributed to conformational differences.