Midesophageal diverticulum with elevated intrabolus pressure: a case report

BACKGROUND

Esophageal diverticulum is commonly associated with esophageal motility disorders, which can be diagnosed using high-resolution manometry (HRM) according to the Chicago classification. Although midesophageal diverticulum (M-ED) is associated with inflammatory processes, esophageal motility disorders have been recently identified as an etiology of M-ED.

CASE PRESENTATION

We present the case of a patient with M-ED and elevated intrabolus pressure (IBP), which did not meet the criteria for esophageal motility disorders according to the Chicago classification. A 71-year-old man presented with gradually worsening dysphagia for two years and was diagnosed as having an 8-cm-long M-ED and multiple small diverticula in lower esophagus. HRM revealed a median integrated relaxation pressure of 14.6 mmHg, a distal latency of 6.4 s, and an average maximum IBP of 35.7 mmHg. He underwent thoracoscopic resection of the M-ED and myotomy, which successfully alleviated the symptoms and reduced the intrabolus pressure to normal levels.

CONCLUSIONS

It is important to recognize the esophageal diverticulum pathology with HRM findings even in cases where the results may not meet the Chicago classification and to include myotomy based on the results.

Downregulation of osteoprotegerin in colorectal cancer cells promotes liver metastasis via activating tumor-associated macrophage

Osteoprotegerin (OPG) is a secreted cytokine that functions as a decoy receptor for receptor activator of nuclear factor kappa-B (RANK) ligand (RANKL). Anti-RANKL treatment for bone metastasis has been widely accepted for solid tumors. However, the mechanism of OPG-RANKL-RANK signaling in systemic colorectal cancer (CRC) metastasis remains unclear. In this study, we investigated the relevance and function of OPG expression in CRC liver metastasis. First, we performed in silico analysis using The Cancer Genome Atlas public database and found that lower OPG expression in CRC was associated with poor overall survival. Immunohistochemistry analyses using resected specimen from patients with CRC in our institute confirmed the result. Patient-matched primary CRC and liver metastases showed a significant downregulation of OPG expression in metastatic lesions. In CRC cell lines, OPG expression did not suppress cell proliferation and migration. However, OPG expression inhibited macrophage migration by suppressing the RANKL-RANK pathway. Moreover, in vivo mouse liver metastasis models showed that OPG expression in CRC cells suppressed liver metastases. In addition, treatment with an anti-RANKL neutralizing antibody also suppressed liver metastases. These results showed that downregulation of OPG expression in CRC cells promotes liver metastasis by activating tumor-associated macrophage, which can become a candidate for targeted therapy with anti-RANKL neutralizing antibody for CRC liver metastasis.

Total gastrectomy as a risk factor for postoperative loss of skeletal muscle in minimally invasive surgery for patients with gastric cancer

PURPOSE

Loss of skeletal muscle mass after gastrectomy for gastric cancer leads to decreased quality of life and poor postoperative survival. However, few studies have examined the postoperative loss of skeletal muscle mass following minimally invasive gastrectomy. This study investigated the impact of minimally invasive total gastrectomy (MI-TG) on changes in skeletal muscle mass during the early postoperative period.

METHODS

Patients who underwent MI-TG or minimally invasive distal or proximal gastrectomy (MI-nonTG) for cStage I-III gastric cancer were retrospectively analyzed (n = 58 vs. 182). Their body composition was measured before surgery and 2 months after surgery. Multivariable linear regression analysis was performed to clarify the impact of the surgical procedure on skeletal muscle index changes using clinically relevant covariates.

RESULTS

Skeletal muscle mass decreased more in the MI-TG group than in the MI-nonTG group (median [interquartile range]; -5.9% [-10.6, -3.7] vs -4.5% [-7.3, -1.9], P = 0.004). In multivariable linear regression analysis using clinically relevant covariates, MI-TG was an independent risk factor for postoperative loss of skeletal muscle mass (coefficient - 2.6%, 95% CI -4.5 to -0.68, P = 0.008).

CONCLUSIONS

Total gastrectomy was a risk factor for loss of skeletal muscle mass during the early postoperative period. If oncologically feasible, proximal or distal gastrectomy with a small remnant stomach should be considered.

Novel and efficient method for culturing patient-derived gastric cancer stem cells

Experimental techniques for patient-derived cancer stem-cell organoids/spheroids can be powerful diagnostic tools for personalized chemotherapy. However, establishing their cultures from gastric cancer remains challenging due to low culture efficiency and cumbersome methods. To propagate gastric cancer cells as highly proliferative stem-cell spheroids in vitro, we initially used a similar method to that for colorectal cancer stem cells, which, unfortunately, resulted in a low success rate (25%, 18 of 71 cases). We scrutinized the protocol and found that the unsuccessful cases were largely caused by the paucity of cancer stem cells in the sampled tissues as well as insufficient culture media. To overcome these obstacles, we extensively revised our sample collection protocol and culture conditions. We then investigated the following second cohort and, consequently, achieved a significantly higher success rate (88%, 29 of 33 cases). One of the key improvements included new sampling procedures for tumor tissues from wider and deeper areas of gastric cancer specimens, which allowed securing cancer stem cells more reproducibly. Additionally, we embedded tumor epithelial pieces separately in both Matrigel and collagen type-I as their preference to the extracellular matrix was different depending on the tumors. We also added a low concentration of Wnt ligands to the culture, which helped the growth of occasional Wnt-responsive gastric cancer stem-cell spheroids without allowing proliferation of the normal gastric epithelial stem cells. This newly improved spheroid culture method may facilitate further studies, including personalized drug-sensitivity tests prior to drug therapy.

Total pelvic exenteration for mucinous adenocarcinoma arising from an implantation cyst 26 years after surgery for rectal cancer

A 47-year-old man underwent low anterior resection for rectal cancer and was surveilled for 5 years without metastasis. Twenty-four years later, the patient developed an implantation cyst at the anastomotic site. Two years after the diagnosis, colonoscopy revealed a disintegrated area in the lesion, and pathological examination of the biopsy specimen revealed adenocarcinoma. Due to the suspicion of invasion into the surrounding organs, the patient underwent laparoscopic total pelvic exenteration after neoadjuvant chemoradiotherapy. A transabdominal and transperineal endoscopic approach was used for safe en bloc excision of the tumor. Pathological examination of the specimen confirmed mucinous adenocarcinoma arising from the implantation cyst. Although an implantation cyst is considered benign, it is important to suspect malignant transformation when its appearance changes. For the accurate diagnosis of implantation cysts, surgeons, endoscopists, and radiologists should be aware of this disease.

Targeting Asparagine Synthetase in Tumorgenicity Using Patient-Derived Tumor-Initiating Cells

Reprogramming of energy metabolism is regarded as one of the hallmarks of cancer; in particular, oncogenic RAS has been shown to be a critical regulator of cancer metabolism. Recently, asparagine metabolism has been heavily investigated as a novel target for cancer treatment. For example, Knott et al. showed that asparagine bioavailability governs metastasis in a breast cancer model. Gwinn et al. reported the therapeutic vulnerability of asparagine biosynthesis in KRAS-driven non-small cell lung cancer. We previously reported that KRAS-mutated CRC cells can adapt to glutamine depletion through upregulation of asparagine synthetase (ASNS), an enzyme that synthesizes asparagine from aspartate. In our previous study, we assessed the efficacy of asparagine depletion using human cancer cell lines. In the present study, we evaluated the clinical relevance of asparagine depletion using a novel patient-derived spheroid xenograft (PDSX) mouse model. First, we examined ASNS expression in 38 spheroid lines and found that 12 lines (12/37, 32.4%) displayed high ASNS expression, whereas 26 lines (25/37, 67.6%) showed no ASNS expression. Next, to determine the role of asparagine metabolism in tumor growth, we established ASNS-knockdown spheroid lines using lentiviral short hairpin RNA constructs targeting ASNS. An in vitro cell proliferation assay demonstrated a significant decrease in cell proliferation upon asparagine depletion in the ASNS-knockdown spheroid lines, and this was not observed in the control spheroids lines. In addition, we examined asparagine inhibition with the anti-leukemia drug L-asparaginase (L-Asp) and observed a considerable reduction in cell proliferation at a low concentration (0.1 U/mL) in the ASNS-knockdown spheroid lines, whereas it exhibited limited inhibition of control spheroid lines at the same concentration. Finally, we used the PDSX model to assess the effects of asparagine depletion on tumor growth in vivo. The nude mice injected with ASNS-knockdown or control spheroid lines were administered with L-Asp once a day for 28 days. Surprisingly, in mice injected with ASNS-knockdown spheroids, the administration of L-Asp dramatically inhibited tumor engraftment. On the other hands, in mice injected with control spheroids, the administration of L-Asp had no effect on tumor growth inhibition at all. These results suggest that ASNS inhibition could be critical in targeting asparagine metabolism in cancers.

Dual blockade of macropinocytosis and asparagine bioavailability shows synergistic anti-tumor effects on KRAS-mutant colorectal cancer

Mutations of KRAS gene are found in various types of cancer, including colorectal cancer (CRC). Despite intense efforts, no pharmacological approaches are expected to be effective against KRAS-mutant cancers. Macropinocytosis is an evolutionarily conserved actin-dependent endocytic process that internalizes extracellular fluids into large vesicles called macropinosomes. Recent studies have revealed macropinocytosis's important role in metabolic adaptation to nutrient stress in cancer cells harboring KRAS mutations. Here we showed that KRAS-mutant CRC cells enhanced macropinocytosis for tumor growth under nutrient-depleted conditions. We also demonstrated that activation of Rac1 and phosphoinositide 3-kinase were involved in macropinocytosis of KRAS-mutant CRC cells. Furthermore, we found that macropinocytosis was closely correlated with asparagine metabolism. In KRAS-mutant CRC cells engineered with knockdown of asparagine synthetase, macropinocytosis was accelerated under glutamine-depleted condition, and albumin addition could restore the glutamine depletion-induced growth suppression by recovering the intracellular asparagine level. Finally, we discovered that the combination of macropinocytosis inhibition and asparagine depletion dramatically suppressed the tumor growth of KRAS-mutant CRC cells in vivo. These results indicate that dual blockade of macropinocytosis and asparagine bioavailability could be a novel therapeutic strategy for KRAS-mutant cancers.

Long-Term Outcomes of Laparoscopic Radical Gastrectomy for Highly Advanced Gastric Cancer: Final Report of a Prospective Phase II Trial (KUGC04)

BACKGROUND

This is the final report evaluating the long-term outcomes of a single-arm phase II clinical trial that demonstrated the short-term efficacy of laparoscopic gastrectomy (LG) for highly advanced gastric cancer (AGC) [KUGC04].

PATIENTS AND METHODS

Seventy-three patients with histologically confirmed gastric adenocarcinoma and diagnosed with clinical stage II or higher, who potentially underwent curative resection between August 2009 and November 2014, were prospectively enrolled. Long-term outcomes with 5-year progression-free survival (PFS) and 5-year overall survival (OS) were evaluated according to clinical or pathological stages. Recurrence and progression patterns were also investigated. These outcomes were compared with those of previous reports to assess the applicability of LG for highly advanced gastric cancer (HAGC).

RESULTS

The median observation period of all surviving patients was 75.1 months. The 5-year PFS and 5-year OS of all patients was 47.4% and 54.4%, respectively. Clinical stage-specific 5-year PFS and 5-year OS was 75.0, 69.1, 53.9, 39.4, 40.0 and 9.1, and 75.0, 68.8, 61.5, 45.0, 60.0 and 27.3, respectively, in stages IIA, IIB, IIIA, IIIB, IIIC, and IV, respectively. Pathological stage-specific 5-year PFS and 5-year OS, including ypStage with preoperative chemotherapy, was 100, 80.0, 100, 62.5, 80.0, 51.3, 16.7, 22.2 and 12.5, and 100, 80.0, 100, 75.0, 80.0, 64.2, 25.0, 33.3 and 12.5, respectively, in stage X (no residual tumor with preoperative chemotherapy), IA, IB, IIA, IIB, IIIA, IIIB, IIIC, and IV, respectively. Recurrence or progression was observed in 30 patients (41.1%).

CONCLUSION

LG for HAGC performed by experienced surgeons is safe and oncologically acceptable.

Generation and Characterization of Patient-Derived Head and Neck, Oral, and Esophageal Cancer Organoids

Esophageal cancers comprise adenocarcinoma and squamous cell carcinoma, two distinct histologic subtypes. Both are difficult to treat and among the deadliest human malignancies. We describe protocols to initiate, grow, passage, and characterize patient-derived organoids (PDO) of esophageal cancers, as well as squamous cell carcinomas of oral/head-and-neck and anal origin. Formed rapidly (<14 days) from a single-cell suspension embedded in basement membrane matrix, esophageal cancer PDO recapitulate the histology of the original tumors. Additionally, we provide guidelines for morphological analyses and drug testing coupled with functional assessment of cell response to conventional chemotherapeutics and other pharmacological agents in concert with emerging automated imaging platforms. Predicting drug sensitivity and potential therapy resistance mechanisms in a moderate-to-high throughput manner, esophageal cancer PDO are highly translatable in personalized medicine for customized esophageal cancer treatments. © 2020 by John Wiley & Sons, Inc. Basic Protocol 1: Generation of esophageal cancer PDO Basic Protocol 2: Propagation and cryopreservation of esophageal cancer PDO Basic Protocol 3: Imaged-based monitoring of organoid size and growth kinetics Basic Protocol 4: Harvesting esophageal cancer PDO for histological analyses Basic Protocol 5: PDO content analysis by flow cytometry Basic Protocol 6: Evaluation of drug response with determination of the half-inhibitory concentration (IC₅₀ ) Support Protocol: Production of RN in HEK293T cell conditioned medium.

Autophagy mitigates ethanol-induced mitochondrial dysfunction and oxidative stress in esophageal keratinocytes

During alcohol consumption, the esophageal mucosa is directly exposed to high concentrations of ethanol (EtOH). We therefore investigated the response of normal human esophageal epithelial cell lines EPC1, EPC2 and EPC3 to acute EtOH exposure. While these cells were able to tolerate 2% EtOH for 8 h in both three-dimensional organoids and monolayer culture conditions, RNA sequencing suggested that EtOH induced mitochondrial dysfunction. With EtOH treatment, EPC1 and EPC2 cells also demonstrated decreased mitochondrial ATPB protein expression by immunofluorescence and swollen mitochondria lacking intact cristae by transmission electron microscopy. Mitochondrial membrane potential (ΔΨm) was decreased in a subset of EPC1 and EPC2 cells stained with ΔΨm–sensitive dye MitoTracker Deep Red. In EPC2, EtOH decreased ATP level while impairing mitochondrial respiration and electron transportation chain functions, as determined by ATP fluorometric assay, respirometry, and liquid chromatography-mass spectrometry. Additionally, EPC2 cells demonstrated enhanced oxidative stress by flow cytometry for mitochondrial superoxide (MitoSOX), which was antagonized by the mitochondria-specific antioxidant MitoCP. Concurrently, EPC1 and EPC2 cells underwent autophagy following EtOH exposure, as evidenced by flow cytometry for Cyto-ID, which detects autophagic vesicles, and immunoblots demonstrating induction of the lipidated and cleaved form of LC3B and downregulation of SQSTM1/p62. In EPC1 and EPC2, pharmacological inhibition of autophagy flux by chloroquine increased mitochondrial oxidative stress while decreasing cell viability. In EPC2, autophagy induction was coupled with phosphorylation of AMP activated protein kinase (AMPK), a cellular energy sensor responding to low ATP levels, and dephosphorylation of downstream substrates of mechanistic Target of Rapamycin Complex (mTORC)-1 signaling. Pharmacological AMPK activation by AICAR decreased EtOH-induced reduction of ΔΨm and ATP in EPC2. Taken together, acute EtOH exposure leads to mitochondrial dysfunction and oxidative stress in esophageal keratinocytes, where the AMPK-mTORC1 axis may serve as a regulatory mechanism to activate autophagy to provide cytoprotection against EtOH-induced cell injury.

Lower Incidence of Postoperative Pulmonary Complications Following Robot-Assisted Minimally Invasive Esophagectomy for Esophageal Cancer: Propensity Score-Matched Comparison to Conventional Minimally Invasive Esophagectomy

BACKGROUND

Whether robot-assisted minimally invasive surgery (RAMIE) is more beneficial than conventional minimally invasive surgery (MIE) remains unclear.

METHODS

In total, 165 consecutive patients with esophageal carcinoma who underwent esophagectomy between January 2015 and April 2020 were retrospectively assessed. A 1:1 propensity score matching analysis was performed to compare the short-term outcomes between RAMIE and conventional MIE.

RESULTS

After matching, 45 patients were included in the RAMIE and conventional MIE groups. RAMIE had a significantly longer total operative time (708 vs. 612 min, P < 0.001) and thoracic operative time (348 vs. 285 min, P < 0.001) than conventional MIE. However, there were no significant differences in terms of oncological outcomes, such as R0 resection rate and number of resected lymph nodes. The overall postoperative morbidity (Clavien-Dindo [C-D] grade II or higher) rate of RAMIE and conventional MIE were 51% and 73% (P = 0.03), respectively, and the severe postoperative morbidity (C-D grade III or higher) rates were 11% and 29% (P = 0.04), respectively. The incidence rate of recurrent laryngeal nerve palsy was halved in RAMIE (7%) compared with conventional MIE (20%) (P = 0.06). Finally, the pulmonary complication rate (18%) was significantly lower in patients who underwent RAMIE than in those who underwent conventional MIE (44%) (P = 0.006).

CONCLUSIONS

RAMIE was safe and feasible, even during the early period of its application at a specialized center. Moreover, it may be a promising alternative to conventional MIE, with better short-term outcomes, including significantly lower incidence of pulmonary complications.

Abstract 501: Aldh2 mutation promotes oral and esophageal cancer stem cells via autophagy-mediated redox homeostasis

Introduction: Heavy alcohol (EtOH) drinking and tobacco smoking increase the risk for upper digestive (e.g. oral and esophageal) squamous cell carcinomas (SCC) in individuals with polymorphic mutations in aldehyde dehydrogenase 2 (Aldh2). Mutant Aldh2E487K protein delays mitochondrial clearance of acetaldehyde, the chief metabolite of EtOH and constituents of tobacco smoke, aka a major human carcinogen. The role of Aldh2 in tumor biology remains elusive.

Methods: Single cell-derived three-dimensional (3D) organoids were generated from murine oral and esophageal preneoplastic and SCC lesions carrying wild-type Aldh2WT or mutant Aldh2E487K as well as human SCC cell lines with Aldh2E487K, the latter subjected to xenograft transplantation in immunodeficient mice. 3D organoids and xenograft tumors were analyzed by morphology and flow cytometry to determine CD44, autophagy (cyto-ID), proliferation (EdU), and reactive oxygen species (ROS) following EtOH exposure ex vivo (0.1-2% EtOH) or in vivo (10% EtOH in drinking water) along with or without inhibitors of alcohol metabolism (4-methylpyrazole; 4MP, siRNA against Adh1B and Cyp2E1), and autophagy flux (chloroquine; CQ or siRNA against Atg7). Flow cytometry was performed to determine cancer stem-like cells with high CD44 expression (CD44H cells).

Results: EtOH stimulated xenograft tumor growth and increased highly proliferative intratumoral CD44H cells with increased autophagy. EtOH-stimulated tumor growth and induction of CD44H cells were sharply suppressed by concurrent 4MP treatment, indicating that EtOH is directly metabolized in SCC cells to promote tumor growth via CD44H cells. These EtOH-induced effects were recapitulated in 3D organoids where Aldh2E487K augmented EtOH-mediated induction of CD44H cells and organoid formation with increased cellular atypia. EtOH induced mitochondrial superoxide and ROS-dependent autophagy activation in CD44H cells. Inhibition of autophagy prevented EtOH from enriching CD44H cells in 3D organoids, suggesting that autophagy may limit alcohol-induced oxidative stress as a cytoprotective mechanism.

Conclusions: These studies provide not only mechanistic insights into the role of Aldh2 mutation in oral and esophageal SCC pathogenesis but also establish the utility of the 3D organoid system to test the functional interplay between genetic and environmental factors which may subsequently be targeted for pharmacological intervention in the setting of personalized medicine.

Citation Format: Masataka Shimonosono, Takashi Kijima, Hisatsugu Maekawa, Satoshi Takada, Koji Tanaka, Varun Sahu, Manti Guha, Andres J. Klein-Szanto, J. Alan Diehl, Adam J. Bass, Anil K. Rustgi, Elizabeth Philipone, Angela J. Yoon, Hiroshi Nakagawa. Aldh2 mutation promotes oral and esophageal cancer stem cells via autophagy-mediated redox homeostasis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 501.

Chemosensitivity of Patient-Derived Cancer Stem Cells Identifies Colorectal Cancer Patients with Potential Benefit from FGFR Inhibitor Therapy

Some colorectal cancer patients harboring FGFR (fibroblast growth factor receptor) genetic alterations, such as copy number gain, mutation, and/or mRNA overexpression, were selected for enrollment in several recent clinical trials of FGFR inhibitor, because these genetic alterations were preclinically reported to be associated with FGFR inhibitor sensitivity as well as poor prognosis, invasiveness, and/or metastatic potential. However, few enrolled patients were responsive to FGFR inhibitors. Thus, practical strategies are eagerly awaited that can stratify patients for the subset that potentially responds to FGFR inhibitor chemotherapy. In the present study, we evaluated the sensitivity to FGFR inhibitor erdafitinib on 25 patient-derived tumor-initiating cell (TIC) spheroid lines carrying wild-type RAS and RAF genes, both in vitro and in vivo. Then, we assessed possible correlations between the sensitivity and the genetic/genomic data of the spheroid lines tested. Upon their exposure to erdafitinib, seven lines (7/25, 28%) responded significantly. Normal colonic epithelial stem cells were unaffected by the inhibitors. Moreover, the combination of erdafitinib with EGFR inhibitor erlotinib showed stronger growth inhibition than either drug alone, as efficacy was observed in 21 lines (84%) including 14 (56%) that were insensitive to erdafitinib alone. The in vitro erdafitinib response was accurately reflected on mouse xenografts of TIC spheroid lines. However, we found little correlation between their genetic/genomic alterations of TIC spheroids and the sensitivity to the FGFR inhibitor. Accordingly, we propose that direct testing of the patient-derived spheroids in vitro is one of the most reliable personalized methods in FGFR-inhibitor therapy of colorectal cancer patients.

MicroRNA-9-5p-CDX2 Axis: A Useful Prognostic Biomarker for Patients with Stage II/III Colorectal Cancer

A lack of caudal-type homeobox transcription factor 2 (CDX2) protein expression has been proposed as a prognostic biomarker for colorectal cancer (CRC). However, the relationship between CDX2 levels and the survival of patients with stage II/III CRC along with the relationship between microRNAs (miRs) and CDX2 expression are unclear. Tissue samples were collected from patients with stage II/III CRC surgically treated at Kyoto University Hospital. CDX2 expression was semi-quantitatively evaluated by immunohistochemistry (IHC). The prognostic impacts of CDX2 expression on overall survival (OS) and relapse-free survival (RFS) were evaluated by multivariable statistical analysis. The expression of miRs regulating CDX2 expression and their prognostic impacts were analyzed using The Cancer Genome Atlas Program for CRC (TCGA-CRC). Eleven of 174 CRC tissues lacked CDX2 expression. The five-year OS and RFS rates of patients with CDX2-negative CRC were significantly lower than those of CDX2-positive patients. Multivariate analysis of clinicopathological features revealed that CDX2-negative status is an independent marker of poor prognosis in stage II/III CRC. miR-9-5p was shown to regulate CDX2 expression. TCGA-CRC analysis showed that high miR-9-5p expression was significantly associated with poor patient prognosis in stage II/III CRC. In conclusion, CDX2, the post-transcriptional target of microRNA-9-5p, is a useful prognostic biomarker in patients with stage II/III CRC.

A Chemosensitivity Study of Colorectal Cancer Using Xenografts of Patient-Derived Tumor-Initiating Cells

Current genomic and gene expression analyses provide versatile tools to improve cancer chemotherapy. However, it is still difficult to predict whether each patient responds to a particular regimen or not. To predict chemosensitivity in each patient with colorectal cancer, we developed an evaluation method using the primary tumor-initiating cells (TIC, aka cancer stem cells) xenografted in nude mice subcutaneously (patient-derived spheroid xenografts; PDSX). Simultaneously, we also prepared the conventional patient-derived xenografts (PDX) from the same patients' tumors and compared the dosing results with those of PDSXs. We further compared the chemosensitivities of PDSXs with those of 7 patients who had been given regimens such as FOLFOX and FOLFIRI to treat their metastatic lesions. As per the results, the PDSX method provided much more precise and predictable tumor growth with less variance than conventional PDX, although both retained the epithelial characteristics of the primary tumors. Likewise, drug-dosing tests showed essentially the same results in PDXs and PDSXs, with stronger statistical power in PDSXs. Notably, the cancer chemosensitivity in each patient was precisely reflected in that of the PDSX mice along the clinical course until the resistance emerged at the terminal stage. This "paraclinical" xenograft trials using PDSXs may help selection of chemotherapy regimens efficacious for each patient, and, more importantly, avoiding inefficient ones by which the patient can lose precious time and QOL. Furthermore, the PDSX method may be employed for evaluations of off-label uses of cancer chemotherapeutics and compassionate uses of yet-unapproved new drugs in personalized therapies. Mol Cancer Ther; 17(10); 2187-96. ©2018 AACR.

An improved method for culturing patient-derived colorectal cancer spheroids

Recent advances allowed culturing and examination of patient-derived colorectal cancer (PD-CRC) cells as organoids or spheroids. To be applied to practical personalized medicine, however, current methods still need to be strengthened for higher efficiency. Here we report an improved method to propagate PD-CRC tumor initiating cells (TICs) in spheroid culture. We established > 100 cancer spheroid lines derived from independent colorectal cancer patients employing a serum-containing medium with additional inhibitors, Y27632 and SB431542. Because colorectal cancer spheroids showed wide-range growth rates depending on the patient tumors, we searched for supplementary factors that accelerated proliferation of slow-growing CRC-TIC spheroids. To this end, we introduced a convenient growth-monitoring method using a luciferase reporter. We found that epidermal growth factor (EGF) and/or basic fibroblast growth factor (bFGF) were critical for steady propagation of a subset of CRC-TIC spheroids carrying the wild-type RAS and RAF genes. We also identified 5'-(N-ethyl-carboxamido)-adenosine (NECA), an adenosine receptor agonist, as an essential supplement for another subset of spheroids. Based on these results, we propose to optimize culture conditions for CRC-TIC spheroids by adjusting to the respective tumor samples. Our method provides a versatile tool that can be applied to personalized chemotherapy evaluation in prospective clinical studies.

Construction and sequencing analysis of scFv antibody fragment derived from monoclonal antibody against norfloxacin (Nor155)

Norfloxacin belongs to the group of fluoroquinolone antibiotics which has been approved for treatment in animals. However, its residues in animal products can pose adverse side effects to consumer. Therefore, detection of the residue in different food matrices must be concerned. In this study, a single chain variable fragment (scFv) that recognizes norfloxacin antibiotic was constructed. The cDNA was synthesized from total RNA of hybridoma cells against norfloxacin. Genes encoding VH and VL regions of monoclonal antibody against norfloxacin (Nor155) were amplified and size of VH and VL fragments was 402 bp and 363 bp, respectively. The scFv of Nor155 was constructed by an addition of (Gly4Ser)3 as a linker between VH and VL regions and subcloned into pPICZαA, an expression vector of Pichia pastoris. The sequence of scFv Nor155 (GenBank No. AJG06891.1) was confirmed by sequencing analysis. The complementarity determining regions (CDR) I, II, and III of VH and VL were specified by Kabat method. The obtained recombinant plasmid will be useful for production of scFv antibody against norfloxacin in P. pastoris and further engineer scFv antibody against fluoroquinolone antibiotics.

Abstract B36: Summary of 50 cases of patient-derived colorectal cancer xenografts; Problems and tips to obtain appropriate results in translational researches

Colorectal cancer (CRC) is one of the most common cancers worldwide, with more than 690,000 deaths estimated in 2012. Despite our increasing knowledge of the genetics of CRC, few biomarkers are available for successful anticancer therapies. The key drugs and therapeutic strategy against CRC are limited. The overall 5-year survival rate of patients with metastatic CRC is only ~12%.

Because of the heterogeneity of CRCs and the complexity in clinical conditions, traditional cell line models have not predicted clinical outcomes of anticancer therapies. Recent studies show that it is difficult to associate the specific genetic mutations with drug sensitivities in vitro. On the other hand, patient-derived tumor xenografts (PDXs) are preferable preclinical models as they preserve the genomic condition and tumor heterogeneity in primary lesions. Although the PDX is costly and time-consuming, its usefulness outweighs these limitations, and it is expected to help not only basic cancer studies but also development of personalized therapies in the clinical setting.

We have been establishing PDXs of advanced CRCs. In short, we dissect fresh tumor fragments (3-5mm cube) from resected tumors by surgical procedure after obtaining patients' informed consents in our hospital. We bring them to our laboratory on ice. We then wash tumor samples with medium twice and with PBS twice. The tumor samples are implanted to each flank of nude mice and/or NOD/SCID mice. The implanted tumor growth is measured at least once a week. We consider the implantation is successful when estimate tumor volumes become more than 1000 mm3. We excise tumor masses, cut and divide them into small fragments, and perform serial transplantation.

We have engrafted 50 cases of CRC tumors so far to establish PDXs. In 23 cases, we confirmed that engrafted tumors were successfully growing. In 8 cases, the implanted tumor disappeared within several weeks after transplantation, and we determined that PDXs in these cases failed to grow as any tumor masses were developed for 6 months. The remaining 19 cases are under study. We found that each PDX, even from the same tumor, showed different growth rate, which made it difficult to set-up PDX panels for drug-sensitivity tests. We conclude that it is rather difficult to prepare an enough number of homogeneous PDX models from each cancer for evaluation of its chemosensitivity. We are currently trying to minimize the growth rate differences of PDXs among individual transplants from a same patient. Such a technique may accelerate translational study using PDXs.

Our future aim is to optimize the care for individual patients with advanced CRC by selecting effective regimens that are predicted by the chemosensitivity test using PDXs. We will also study several genetic mutations that affect patient survival rate and their relationship with chemo-sensitivities so that we can improve CRC patient survival in our hospital.

Citation Format: Hisatsugu Maekawa, Tadanori Yamaura, Kenji Kawada, Yoshiharu Sakai. Summary of 50 cases of patient-derived colorectal cancer xenografts; Problems and tips to obtain appropriate results in translational researches. [abstract]. In: Proceedings of the AACR Special Conference: Patient-Derived Cancer Models: Present and Future Applications from Basic Science to the Clinic; Feb 11-14, 2016; New Orleans, LA. Philadelphia (PA): AACR; Clin Cancer Res 2016;22(16_Suppl):Abstract nr B36.

Effect of antiplatelet therapy on patients undergoing gastroenterological surgery: thromboembolic risks versus bleeding risks during its perioperative withdrawal

BACKGROUND

Antiplatelet agents given to prevent thromboembolic disease are frequently withdrawn prior to surgical procedures to reduce bleeding complications. This action may expose patients to increased thromboembolic morbidity and mortality.

METHODS

A series of 2012 patients who had undergone gastroenterologic surgery between January 2005 and June 2010 at our institution were reviewed. Among this cohort, antiplatelet therapy (APT) was used in 519 patients (25.8 %). The perioperative management included interruption of APT 1 week before surgery and early postoperative reinstitution in patients at low thromboembolic risk, although APT was maintained until surgery in those at high thromboembolic risk. Bleeding and thromboembolic complications, as well as other outcome variables, were assessed in patients with and without APT.

RESULTS

Among 519 patients with APT, 99 (19.1 %) underwent multidrug APT. Among them, 124 (23.9 %) required preoperative continuation of APT. None suffered from excessive bleeding intraoperatively. There were 19 thromboembolic events (0.9 %) in the whole cohort. Postoperative bleeding complications occurred in 37 patients (1.8 %). Multivariate analysis showed that increased postoperative bleeding complications were independently associated with multidrug APT [hazard ratio (HR) 4.3, p = 0.014], high-risk surgical procedures (HR 3.5, p = 0.003), and perioperative heparin bridging (HR 2.8, p = 0.029). High-risk surgery (HR 8.3, p < 0.001) and poor performance status (HR 4.9, p = 0.005)--but neither APT nor anticoagulation use--were significant prognostic factors for thromboembolic complications.

CONCLUSIONS

Satisfactory outcomes were obtained during gastroenterologic surgery under rigorous perioperative management, including single-agent APT continuation in patients at high thromboembolic risk. Patients treated with multidrug APT still represent a challenging group, however, and need to be carefully managed to prevent perioperative complications.

[A case of adenocarcinoma occurring in the bladder mucosa after a surgical operation for colovesical fistula]

We report a case of adenocarcinoma occurring in the bladder mucosa 6 years after a surgical operation for colovesical fistula due to colonic diverticulitis of the sigmoid colon. The patient was a 76-year-old woman who had undergone a sigmoidectomy and ligation of the colovesical fistula at the age of 70 years. She presented with a complaint of gross hematuria. Cystoscopy and computed tomography revealed bladder cancer at the site of the original colovesical fistula surgery. She underwent transurethral resection of the bladder tumor. Histopathological findings revealed intestinal adenocarcinoma in the urinary bladder. A radical partial cystectomy was subsequently performed because of a positive and involved margin. This tumor may have originated from the bladder mucosa and then replaced by intestinal metaplastic cells that originated from the same initiating event.

Metachronous biliary carcinoma with intraductal pancreatic adenocarcinoma 13 years after curative resection of hilar bile duct cancer

We report a case of a 68-year-old woman with metachronous bile duct cancer and a pancreatic adenocarcinoma. She had undergone extended left hepatic lobectomy for hilar bile duct carcinoma. However, when she was admitted to our hospital 13 years later for an annual follow-up, abdominal CT revealed a mass in the dilated remnant of her lower bile duct. This was diagnosed as a second primary tumour, a pancreaticoduodenectomy was performed and 15 months after the second operation, she remains recurrence-free. Nineteen cases of patients with metachronous bile duct carcinomas were identified in the literature and have been reviewed.

Aggressive secondary surgery for local recurrence of pancreatic cancer

We report two cases of locally recurrent pancreatic cancer treated with repeated resection. In both cases, local recurrence was found in the cut end of the remnant pancreas after initial pancreatic resection, and total remnant pancreatectomy was performed. The postoperative course was uneventful and long-term survival was achieved. Aggressive repeated surgical resection could improve the prognosis of selected patients who are suffering from local recurrence of pancreatic cancer, and can be considered as a treatment option.

Exploration and characterization of genes involved in the synthesis of diterpene defence secretion in nasute termite soldiers

Nasutitermes takasagoensis soldiers defend their colonies using characteristic diterpenes. Diterpenes are thought to be synthesized in the frontal gland cells surrounding the gland reservoir. To identify the genes involved in diterpene synthesis, a cDNA library was prepared from the frontal gland cells and exhaustively sequenced using a 454 pyrosequencer (GS Junior; Roche, Branford, CT, USA). A total of 50,290 clean sequences were assembled into 1111 contigs, which were grouped into 774 genes (isogroups). Based on sequence similarity with known proteins, we identified seven genes encoding the following four enzymes associated with diterpene synthesis: 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) synthase (HMGS), HMG-CoA reductase (HMGR), farnesyl diphosphate synthase, and geranylgeranyl diphosphate synthases. The expression levels of two enzymes, HMGS and HMGR, involved in the mevalonate pathway were examined, assuming that the site of the defensive terpenoid synthesis strongly activates the mevalonate pathway, which produces a precursor of terpenoids. Real-time quantitative reverse-transcriptase PCR confirmed significantly higher expression of HMGS and HMGR in the heads of soldiers. We then divided the head into three parts and found that the expression levels of HMGS and HMGR were significantly higher in the part containing class 1 secretory cells of the frontal gland. Overall, the results suggested that the mevalonate pathway for diterpene synthesis occurs in class 1 cells around the frontal gland reservoir.

Successful laparoscopic investigation and resection of solitary colonic metastasis from breast cancer (with video)

Metastasis to gastrointestinal tract from breast cancer is an uncommon situation. We report a case of a 52-year-old woman who had a mastectomy for solid-tubular carcinoma of the breast 16 years ago and bilateral salpingo-oophorectomy for metastatic ovarian tumours 5 years ago, was incidentally found to have colonic metastatic tumour detected by positron emission tomography/CT (PET/CT) during follow-up. After identifying a definite location of the tumour in the ascending colon under laparoscopic investigation, laparoscopy-assisted partial colectomy was successfully performed. Histopathology of the resected specimen showed it to be metastasis from solid-tubular carcinoma of the breast. We should be aware that breast cancer can metastasise to the gastrointestinal tract even after the long interval from initial therapy. An index of high suspicion and detailed assessment is mandatory to make a correct diagnosis and following less invasive surgical treatment.

Successful resection of complicated bleeding arteriovenous malformation of the jejunum in patients starting dual-antiplatelet therapy just after implanting a drug-eluting coronary stent

We report a case of a 57-year-old man who started dual-antiplatelet therapy with aspirin and clopidogrel following implantation of drug-eluting coronary stent and developed persistent active gastrointestinal bleeding. After detecting the origin of bleeding by double-balloon enteroscopy, successful laparoscopy-assisted partial jejunal resection was performed and the patient condition was promptly recovered, without any thrombotic or bleeding complications. Pathology revealed arteriovenous malformation of the jejunum without any malignancy. We should care for and be aware of this lesion as a rare cause of gastrointestinal bleeding when strong antithrombotic therapy is initiated. Under rigorous assessment and perioperative management, as well as meticulous intraoperative dissection and haemostasis, satisfactory outcome was achieved even in this complicated situation.

Fatal hemorrhage in cerebral proliferative angiopathy

Cerebral proliferative angiopathy (CPA) is a rare vascular abnormality with several angiomorphological features that are distinct from brain arteriovenous malformations (AVMs). The natural history of CPAs indicates a lower risk for hemorrhage compared to brain AVMs. A 62-year-old woman presented with gait instability and dysarthria. MRI and angiography revealed a diffuse vascular network involving the tectum and cerebellar vermis with intermingled brain parenchyma. This lesion had no dominant feeder, high-flow arteriovenous shunt, flow-related aneurysm or highly dilated veins on angiogram. These findings were consistent with a diagnosis of CPA. During follow-up, she developed progressive gait instability and eye movement abnormalities, but no remarkable change was detected on the repeated MRI and angiography. Nine years later, she died of mesencephalic hemorrhage originating from the CPA. To the best of our knowledge, this is the first description of a patient with CPA who died as a result of the initial hemorrhage. It is important to recognize that a part of CPAs is aggressive and can be more vulnerable to critical hemorrhage.

[A case of unresectable hilar cholangiocarcinoma successfully treated by gemcitabine and S-1 combination chemotherapy]

A 52-year-old male was presented with obstructive jaundice and liver dysfunction. He was diagnosed as hilar cholangiocarcinoma involving the confluence of the right and left hepatic duct and bifurcation of the main portal vein trunk. Swollen lymph nodes in the hepatoduodenal ligament were also detected. ERBD tubes were placed in each B2, 3, and 5 branch. GEM and S-1 combination chemotherapy was carried out for four months. As a reduction in the primary tumor and lymph nodes was observed on CT scan surgical exploration was conducted, and an extended left hepatectomy with partial resection of the portal vein and regional lymph node dissection was achieved. The postoperative course was uneventful, and the patient remained free of recurrence, 34 months after the original diagnosis was made, and 29 months after surgical resection. Thus, GEM and S-1 combination chemotherapy is one of the options for the management of advanced hilar cholangiocarcinoma.

[A long survival of a patient with poor performance status who suffered from advanced right breast cancer with multiple lung metastases controlled by trastuzumab as a key drug]

We report a case of a 60-year-old woman with poor performance status (PS). She suffered from advanced right breast cancer with multiple lung metastases, which was controlled by chemotherapy with trastuzumab as the key drug. The patient presented with a 4 cm-sized large right breast mass. Her PS was poor due to progressive spinocerebellar degeneration. The biopsy specimen of the breast mass showed scirrhous type of the invasive ductal carcinoma (ER+, HER2 2+). Multiple lung metastases were also detected by computed tomography. Considering her poor PS, the patient was treated with mild systemic therapy using trastuzumab as the key drug. A different drug response was achieved between the breast mass and lung metastatic lesions, and the tumors were maintained as stable disease (SD) during first 18 months. However, she finally passed away due to respiratory failure resulting from lung metastasis, 33 months after starting treatment. The autopsy findings showed a difference of HER2 expression between the breast tumor and lung metastatic lesions. It must be recognized that differences of HER2 expression between the primary tumor and metastatic lesions are sometimes demonstrated in patients with breast cancer, and that trastuzumab can be used as a key drug in some patients as in the current case.

Undifferentiated carcinoma of the common bile duct with intraductal tumor thrombi: report of a case

We report a case of undifferentiated carcinoma of the common bile duct with intraductal tumor thrombi. A 73-year-old man presented with general malaise. Abdominal computed tomography and magnetic resonance imaging revealed a mass in the distal common bile duct, accompanied by dilatation of the intra- and extrahepatic bile ducts. The patient underwent pancreaticoduodenectomy with regional lymphadenectomy. Gross examination revealed that the distal common bile duct was obstructed by an elastic hard mass, 3.2 × 2.6 cm, accompanied by intraductal tumor thrombi. Microscopically, the nodule was well defined and composed of atypical large tumor cells with bizarre nuclei and little cytoplasm. Immunohistochemically, the tumor cells were diffusely positive for cytokeratin-7 and CAM5.2, but negative for CD56, chromogranin A, and synaptophysin. Thus, a histological diagnosis of undifferentiated carcinoma of the common bile duct was made. The patient recovered uneventfully and has remained free of any signs of recurrence for 18 months since the operation. Undifferentiated carcinomas of the extrahepatic bile duct can be detected early, with the chance of a good prognosis; however, because their biologic growth behavior is still considered aggressive, careful observation after surgery and the initiation of multidisciplinary treatment against recurrence are necessary.

Development of a nuclear magnetic resonance system for in situ analysis of hydrogen storage materials under high pressures and temperatures

A NMR system for in situ analysis of hydrogen storage materials under high pressure and temperature conditions was developed. The system consists of a gas pressure and flow rate controlling unit, a temperature controller, a high temperature NMR probe tunable for both (1)H and other nuclei, and a sample tube holder. Sample temperature can be controlled up to 623 K by heated N(2) gas flow. Sample tube atmosphere can be substituted by either H(2) or Ar and can be pressurized up to 1 MPa under constant flow rate up to 100 ml/min. During the NMR measurement, the pressure can be adjusted easily by just handle a back pressure valve. On the blank NMR measurement, (1)H background noise was confirmed to be very low. (1)H and (11)B NMR spectrum of LiBH(4) were successfully observed at high temperature for the demonstration of the system. The intensity of the (1)H NMR spectra of H(2) gas was also confirmed to be proportional to the applied pressure.

Influence of nitrogen fertilization on tropical-grass silage assessed by ensiling process monitoring using chemical and microbial community analyses

AIMS

Utilization of silage in livestock farming is expected to increase in developing countries in the tropical and subtropical parts of the world. The aim of this study was to investigate the influence of nitrogen fertilization on the chemical composition of herbage, ensiling process and silage quality, and to contribute to the improvement of tropical-grass silage preparation.

METHODS AND RESULTS

Guinea grass grown under two different nitrogen-fertilizer application conditions [1.5 kg N a(-1) (high-N) and 0.5 kg N a(-1) (low-N)] was packed in plastic bags, and its ensiling process was investigated by chemical and microbial-community analyses. Relatively well-preserved silage was obtained from high-N herbage, which accumulated a high nitrate concentration. Denaturing gradient gel electrophoresis analysis revealed that Lactobacillus plantarum dominated throughout the ensiling of high-N herbage and in the early phase of that of low-N herbage. In low-N silages prepared from ammonium sulfate- and urea-fertilized herbage, Lact. plantarum was replaced by clostridia after 40 and 15 days of ensiling, respectively.

CONCLUSIONS

Nitrate content of herbage is an important factor that influences silage quality, and careful fertilization management can facilitate stable and successful fermentation of tropical-grass silage without any pretreatment.

SIGNIFICANCE AND IMPACT OF THE STUDY

The positive effect of nitrate on the ensiling process of tropical-grass was proved by microbial-community analysis.

Hierarchical dynamics of As2P2S8 quasi-molecular units in a supercooled liquid in the As-P-S system: a 31P NMR spectroscopic study

The dynamics of As2P2S8 quasi-molecular units caged in an As-S network in the supercooled chalcogenide liquid of composition (As2S3)90(P2S5)10 have been studied near the glass transition region (Tg=468<or=T<or=628 K) using 31P NMR line shape analysis and spin-lattice relaxation techniques. 31P NMR line shape analysis indicates the presence of isotropic rotational reorientation of As2P2S8 quasi-molecular units at frequencies on the order of tens of kilohertz at T<540 K. At higher temperatures, the time scale of intramolecular bond-breaking and rearrangement is coupled to that of shear/structural relaxation of the surrounding network. On the other hand, over the entire temperature range, the 31P NMR spin-lattice relaxation results from fast cage-rattling dynamics of the same molecules at frequencies in the megahertz to gigahertz range. When taken together, these results imply the presence of serial hierarchical dynamics in which the fast rattling of As2P2S8 quasi-molecular units trapped in their cages coexists with slower isotropic rotational reorientation. The shear or alpha-relaxation involves cooperative rearrangement of the surrounding As-S network and, consequently, relaxation of the cages that provides feedback to the fast rattling dynamics over the entire temperature range.

The Tokyo subway sarin attack--lessons learned

The sarin gas attack in the Tokyo subway system is reviewed from a clinical toxicology perspective. Based on the lessons learned from this attack, the following areas should be addressed on a global scale. First, an adequate supply of protective equipment is required, including level B protective equipment with a pressure demand breathing apparatus. In addition, a system should be established that enables a possible cause to be determined based on symptoms, physical findings, general laboratory tests, and a simple qualitative analysis for poisonous substances. If an antidote is needed, the system should enable it to be administered to the victims as quickly as possible. Preparation for a large-scale chemical attack by terrorists requires the prior establishment of a detailed decontamination plan that utilizes not only mass decontamination facilities but also public facilities in the area. A system should be established for summarizing, evaluating, and disseminating information on poisonous substances. Finally, a large-scale scientific investigation of the Tokyo sarin attack should be conducted to examine its long-term and subclinical effects and the effects of exposure to asymptomatic low levels of sarin.

Transfer of cholesterol and diacylglycerol from lipophorin to Bombyx mori ovarioles in vitro: role of the lipid transfer particle

The objective of this study was to characterize the transfer of diacylglycerol (DAG) and cholesterol from larval Bombyx mori lipophorin to ovarioles. Transfer studies were carried out by incubating pupal ovarioles (5-day) with [(3)H]-cholesterol and [(3)H]-DAG-labeled lipophorin under different conditions. Transfer of both cholesterol and DAG exhibited hyperbolic dependency on lipophorin concentration with apparent Km values of 0.83 +/- 0.17 mg/ml and 0.74 +/- 0.16 mg/ml, respectively. Pretreatment of ovarioles with anti-lipid transfer particle (LTP) IgG significantly inhibited transfer of labeled DAG to ovarioles (75%) and not cholesterol. Injection of B. mori pupae (day 4) with anti-LTP IgG significantly affected the weight (65%), number of eggs (49%), amount of lipid (74%), and protein (65%) of the adult ovaries. Matured eggs had a very faint yellow color and deformed shape compared to controls. The inhibitory effect demonstrates the active role LTP plays in growth of ovaries, development, and oogenesis. The effect on vitellogenin shortage on egg development and maturation was determined by implanting ovaries in male recipients that lack vitellogenin. An 80% decline in egg production was observed. However, the mature eggs were normal in shape, color, and lipid content. Thus, restricting lipid or protein delivery to developing ovaries would dramatically affect choriogenesis.

Extensive mesenteric vein and portal vein thrombosis successfully treated by thrombolysis and anticoagulation

Mesenteric vein thrombosis is generally difficult to diagnose and can be fatal. A case of extensive thrombosis of the mesenteric and portal veins was diagnosed early and successfully treated in a 26-year-old man with Down syndrome who was admitted to hospital because of abdominal pain, severe nausea and high fever. Ultrasonography revealed moderate ascites, and there was minimal flow in the portal vein (PV) on the Doppler examination. Computed tomography (CT) showed remarkable thickening of the walls of the small intestine and extensive thrombosis of the mesenteric, portal and splenic veins. Because neither intestinal infarction nor peritonitis was seen, combined thrombolysis and anticoagulation therapy without surgical treatment was chosen. Urokinase was administered intravenously and later through a catheter in the superior mesenteric artery. Heparin and antibiotics were given concomitantly. The patient's symptoms and clinical data improved gradually. After 10 days, CT revealed that collateral veins had developed and the thrombi in the distal portions of the mesenteric veins had dissolved, although the main trunk of the PV had not recanalized. The only risk factor of thrombosis that was detected was decreased protein S activity.

Mg-promoted regio- and stereoselective C-acylation of aromatic alpha,beta-unsaturated carbonyl compounds

[reaction: see text]. Treatment of aromatic alpha,beta-unsaturated carbonyl compounds with Mg turnings in the presence of acid anhydrides/TMSCl or acyl chlorides in DMF brought about a facile and efficient cross-coupling to give C-acylation products, which are useful 1,4-dicarbonyl compounds, in good to excellent yields in a regio- and stereoselective manner. The reaction may be initiated by electron transfer from magnesium to the substrates.

Esophageal smooth muscle tumor in a 25-year-old woman with congenital malformations

We recently treated a 25-year-old woman with an esophageal smooth muscle tumor with congenital malformations. Although the large size of the tumor and the presence of hemonecrotic lesion suggested the tumor to be leiomyosarcoma, histological studies revealed it to be leiomyoma. According to previous reports in the English-language literature, the coincidence of esophageal smooth muscle tumor with congenital malformations is relatively rare, and the coincidence of such a tumor with malformations of the type seen in this patient has never been reported. The congenital malformations in our patient were ocular hypertelorism, platyrrhiny, bilateral divergent strabismus, clubbed fingers and toes, fingerprint abnormality, and mild mental retardation. These congenital malformations cannot be explained by any reported syndromes.

IgG1 anti-P2 as a marker of response to interferon in patients with chronic hepatitis C

To study the relations of antibody production to long-term outcomes after interferon (IFN) treatment in patients with chronic hepatitis C (CH-C), we used ELISA to measure the levels of antibodies against HCV core protein and peptides. Samples from 21 complete responders and 36 non-responders were collected before IFN therapy, soon after the end of IFN therapy and 6 months later. Using a set of 19 synthesized HCV core peptide antigens, we found that anti-P2 (11-25a.a.) was the most prevalent of all IgG antibodies (93%: 39/42). Among complete responders, IgG1 anti-P2 levels had fallen by the end of IFN therapy (from 79.8 +/- 60.4-46.1 +/- 44.2: P < 0.01), and were lower still 6 months after the end of IFN therapy (31.0 +/- 35.2: P < 0.001); this change was the greatest of all antibodies studied. Among the non-responders, there was no change within the follow-up period. Soon after the end of IFN therapy, IgG1 anti-P2 levels were more than 30% lower than the initial value in more than two-thirds of the complete responders, but in only one-third of the non-responders (14/20 vs. 8/25: P < 0.05). Six months after the end of IFN therapy, IgG1 anti-P2 levels were more than 30% lower than the initial value in more than 85% of the complete responders, but in only 12% of the non-responders (17/20 vs. 3/25: P < 0.001). In conclusion, the changes in levels of IgG1 anti-P2 paralleled the activity of chronic hepatitis C after IFN therapy, and IgG1 anti-P2 levels may be markers of the efficacy of IFN therapy.

Role of central nervous system nitric oxide in the development of neurogenic pulmonary edema in rats

OBJECTIVE

The present study was undertaken to evaluate roles of nitric oxide in the central nervous system in the development of neurogenic pulmonary edema. Nitric oxide donor compounds have been reported to be effective for controlling some kinds of pulmonary edema.

DESIGN

Randomized trial.

SETTING

Experimental university pharmacology laboratory.

SUBJECTS

Wistar rats anesthetized with pentobarbital.

INTERVENTIONS

Neurogenic pulmonary edema was induced by injections of fibrinogen and thrombin into the cisterna magna. Physiologic roles of nitric oxide were evaluated by using NG-nitro-l-arginine methyl ester (a nitric oxide synthase inhibitor) or l-arginine (a nitric oxide donor compound). Vagus nerves were either left intact or bilaterally severed 20 mins before the injections of fibrinogen and thrombin.

MEASUREMENTS AND MAIN RESULTS

Because enhanced sympathetic nerve activity mediates neurogenic pulmonary edema, the concentration of neuropeptide Y, a neurotransmitter, in edema fluid was measured by using enzyme-linked immunosorbent assay. To evaluate the severity of pulmonary edema and pulmonary vascular permeability, lung water content and protein concentration in edema fluid were analyzed. In rats with intact vagus nerves, injection of NG-nitro-l-arginine methyl ester into the cisterna magna worsened the pulmonary edema, whereas l-arginine had no effect. In contrast, in vagotomized rats, l-arginine abrogated pulmonary edema, whereas NG-nitro-l-arginine methyl ester exerted no influence. Likewise, the ratio of edema fluid protein to serum protein and the neuropeptide Y concentration were increased by NG-nitro-l-arginine methyl ester in rats with the vagus nerves intact and were diminished by l-arginine in vagotomized rats.

CONCLUSIONS

Neurogenic pulmonary edema is characterized by elevated pulmonary vascular permeability and may be inhibited by nitric oxide production in the medulla oblongata.

Pseudolymphoma of the liver associated with Sjögren's syndrome

Sjögren's syndrome (SS) is known to be associated with pseudolymphoma in several organs. We describe a patient with SS complicated by a hepatic pseudolymphoma. Although the development of a hepatic pseudolymphoma is extremely rare, this disorder should be taken into consideration in the differential diagnosis of space occupying lesions related to autoimmune diseases such as SS.

The MEK1-ERK map kinase pathway and the PI 3-kinase-Akt pathway independently mediate anti-apoptotic signals in HepG2 liver cancer cells

Primary liver cancers, which are generally hypervascular in nature, depend highly on blood supply. So far there are few reports on apoptosis of liver cancer cells upon deprivation of serum-derived survival factors. The aim of our study is to clarify molecular mechanisms by which liver cancer cells survive with the aid of serum. In HepG2 liver cancer cells, serum deprivation induced time-dependent increase in the number of apoptotic cells, which was detected by fragmentation of genomic DNA and fluorescent nuclear staining. The activity of extracellular signal-regulated kinase (ERK) did not decrease considerably after serum deprivation, although it increased after serum stimulation. However, we found that the MEK1 inhibitor PD98059, but not the p38 kinase inhibitor SB203580, potently induced apoptosis of the liver cancer cells in the presence of serum, indicating that the MEK-ERK signaling pathway is required for serum-dependent survival of HepG2 cells. In agreement with this notion, transient expression of active MEK1 prevented apoptosis in serum-deprived condition. We also found that the protective effect of serum against apoptosis was totally abrogated by LY294002 or wortmannin, which are the inhibitors of phosphatidylinositol (PI) 3-kinase. The activity of Akt, the target of PI 3-kinase, decreased gradually after deprivation of serum, whereas it was rapidly reactivated upon serum stimulation. These data indicate that survival of HepG2 liver cancer cells depends upon serum and that both the MEK1-ERK- and the PI 3-kinase-Akt- pathways are required for survival signaling to the nucleus.

Thrombin inhibition by HCII in the presence of elastase-cleaved HCII and thrombin-HCII complex

The rate of thrombin inhibition by heparin cofactor II (HCII) is facilitated by heparin or dermatan sulfate in vitro. The distributions of these glycosaminoglycans (GAGs) in vivo are not the same; heparin-like substance is rich on the surface of endothelial cells and dermatan sulfate is relatively dominant in the extravascular region. When inflammation takes place, at least two other possible existent forms of HCII, the complexed form with thrombin and the cleaved form by leukocyte elastase, are assumed to be present at relatively high concentrations in a local circumstance. We examined the interactions of HCII with the two forms of HCII on thrombin inhibition in the presence of the GAGs. By HCII in complex with thrombin or cleaved by leukocyte elastase, the affinity of HCII moiety for heparin increases and that for dermatan sulfate decreases. The two forms possibly occur at relatively high concentrations in a local pathological situation, although the heparin cofactor activity for thrombin inhibition by HCII decreases and dermatan sulfate determines the cofactor activity. These results indicate efficient thrombin inhibitory activity of HCII in the extravascular region.

Lysophosphatidic acid enhances collagen gel contraction by hepatic stellate cells: association with rho-kinase

We studied the effect of lysophosphatidic acid (LPA) on collagen gel contraction by cultured rat hepatic stellate cells (HSCs) in association with the function of Rho-kinase, one of the target molecules of small GTPase Rho. Binding studies showed a single class-binding site of LPA on HSCs. LPA enhanced the contraction of a collagen lattice seeded with HSCs. LPA increased the number of HSCs with polygonal morphology that contained actin stress fibers, and enhanced the phosphorylation of myosin light chain and the assembly of focal adhesion kinase and RhoA around fibronectin-coated beads seeded on HSCs. The electric cell-substrate impedance sensor system showed that LPA enhanced adhesion of HSC to extracellular substrate. All the effects of LPA were suppressed by Y-27632, Rho-kinase inhibitor. These data support the notion that LPA is involved in modulating HSC morphology, its attachment to surrounding extracellular matrix and its contraction by a mechanism involving Rho-kinase.