Post-treatment magnetic resonance imaging predicts outcomes of maxillary sinus cancer treatment using super-selective intra-arterial infusion of high-dose cisplatin with concomitant radiotherapy (RADPLAT)

OBJECTIVES

This study aimed to evaluate the prognostic value of magnetic resonance imaging (MRI) findings in predicting local recurrence in patients with maxillary sinus cancer treated with super-selective intra-arterial infusion of high-dose cisplatin with concomitant radiotherapy (RADPLAT).

METHODS

This single-center retrospective study included consecutive patients with maxillary sinus squamous cell carcinoma, who underwent RADPLAT between October 2016 and September 2021. MRI was performed before (within 2 weeks) and 1 month after (post-treatment MRI) the start of treatment. Tumor reduction rates and pre-treatment cross-sectional areas were calculated from the maximum cross-sectional areas on pre- and post-treatment MRI T2-weighted axial images. Statistical analyses, including receiver operating characteristic analysis, were performed to assess the predictive value of the tumor reduction rates.

RESULTS

Twenty-four patients were included in this study. Recurrence occurred in seven patients with a median time of 213 days. The tumor reduction rates were significantly higher in the benign post-treatment changes group compared to the recurrence group (median, 0.814 vs. 0.174; p < 0.001). The cut-off value for the reduction rate between the groups was 0.3578. No significant difference was observed in the maximum pre-treatment cross-sectional area between the groups (p = 0.664). The inter-observer agreement for the tumor areas was excellent.

CONCLUSIONS

The tumor reduction rate calculated from MRI T2-weighted images may be a predictor of local recurrence in patients with maxillary sinus cancer treated with RADPLAT. Patients with lower reduction rates may benefit from early salvage surgeries.

Exclusive Transcervical Drainage for Posterior Mediastinal Abscess Originating from a Mandibular Molar

The progression of a cervical abscess toward the mediastinum is rare but remains one of the most serious diseases, even in the era of antibiotics. A mediastinal abscess can originate from an odontogenic infection and presents a challenge for otolaryngologists and craniofacial surgeons, particularly when it spreads caudally to the tracheal bifurcation. For successful treatment of such an abscess, patients are generally referred to a thoracic surgeon for drainage. We present a distinctive case of an odontogenic infection-induced wide mediastinal abscess that could be drained only through cervical manipulation by using a sump-type tube. The patient was discharged on postoperative day 55 without any complications. This is the first report showing that descending mediastinal abscesses extending below the tracheal bifurcation could be drained by head and neck surgeons alone. The technique is easy and hence reproducible, safe, and convenient to perform.

A rare case of epithelial-myoepithelial carcinoma ex pleomorphic adenoma of the parotid gland: Radiologic-pathologic correlation

Carcinoma ex pleomorphic adenoma is a carcinoma that arises from a primary or recurrent benign pleomorphic adenoma. The prevalence of epithelial-myoepithelial carcinoma is low, and this histological type accounting for only 1% of all salivary gland tumors. Here, we report a rare case of Epithelial-Myoepithelial Carcinoma ex pleomorphic adenoma of the parotid gland with a radiologic-pathologic correlation.

Endoscopic-assisted total maxillectomy with precise surgical margins

In traditional open maxillectomy, identifying the posterior margin is difficult because of its deep location and bleeding from the pterygoid venous plexus. Here, we present our endoscope-assisted total en bloc maxillectomy technique and discuss its merits and demerits compared to previously reported methods. We developed an endoscope-assisted total en bloc maxillectomy procedure. We reviewed a series of total maxillectomies performed with and without endoscopic assistance to verify the advantages of endoscopic assistance over conventional total maxillectomy. We analyzed (1) the precision using the distance of the remaining pterygoid process, (2) the operation time, and (3) blood loss. The length of the remnant pterygoid process was significantly shorter in the endoscopic assistance group. The operation time and blood loss were not significantly different between the two groups. Endoscopic assistance makes total maxillectomy more precise without requiring additional time and is a reasonable option for total maxillectomies.

Structural determination of the cell wall polysaccharide LCPS-1 in Lacticaseibacillus paracasei strain Shirota YIT 9029

The neutral polysaccharides LCPS-1 and LCPS-2 play functional roles in the cell wall of the lactic acid bacterium Lacticaseibacillus paracasei strain Shirota YIT 9029 (LcS; formerly Lactobacillus casei strain Shirota YIT 9029), which has long been used as a probiotic food product. Studies have shown that LCPS-1 is associated with the immunomodulatory functions of LcS. We hypothesized that the structure of LCPS-1 is crucial for elucidating the mechanism of action of LcS on host immune responses and aimed to solve the undetermined primary structure of LCPS-1. Our results showed that LCPS-1 has a molecular weight of >400 kDa and is composed of Glc, Rha, Gal, and GlcNAc, with a repeating structure. Using limited degradation reactions, including controlled Smith and deamination degradations, we obtained key fragments with low molecular weight. Subsequently, their structures were analyzed using NMR spectra and other analytical techniques. Further, we integrated the results for each key fragment to derive the complete structure of LCPS-1. Our results indicated that the most probable structure of LCPS-1 is composed of two types of units (X, Y), each with a basic structure of seven sugars in which the C2-position of Rha is substituted with an acetyl group. The structure of X is {6[Glcβ1-2] Galα1-3[2-OAc] Rhaβ1-4Glcβ1-4[Rhaα1-3] [Glcα1-6] Glcβ1-} and that of Y is {6[Glcβ1-2] Galα1-3[2-OAc] Rhaβ1-4Glcβ1-4[Rhaα1-3] [Glcα1-6)] GlcNAcβ1-}, which can be expressed as (X₆Y₁₂)_n. In this study, we identified the primary structure of LCPS-1, and our results may enable an improved understanding of the immunomodulatory abilities of LcS.

Wall teichoic acid-dependent phagocytosis of intact cell walls of Lactiplantibacillus plantarum elicits IL-12 secretion from macrophages

Selected lactic acid bacteria can stimulate macrophages and dendritic cells to secrete IL-12, which plays a key role in activating innate and cellular immunity. In this study, we investigated the roles of cell wall teichoic acids (WTAs) displayed on whole intact cell walls (ICWs) of Lactiplantibacillus plantarum in activation of mouse macrophages. ICWs were prepared from whole bacterial cells of several lactobacilli without physical disruption, and thus retaining the overall shapes of the bacteria. WTA-displaying ICWs of several L. plantarum strains, but not WTA-lacking ICWs of strains of other lactobacilli, elicited IL-12 secretion from mouse bone marrow-derived macrophages (BMMs) and mouse macrophage-like J774.1 cells. The ability of the ICWs of L. plantarum to induce IL-12 secretion was abolished by selective chemical elimination of WTAs from ICWs, but was preserved by selective removal of cell wall glycopolymers other than WTAs. BMMs prepared from TLR2- or TLR4-deficient mouse could secret IL-12 upon stimulation with ICWs of L. plantarum and a MyD88 dimerization inhibitor did not affect ICW-mediated IL-12 secretion. WTA-displaying ICWs, but not WTA-lacking ICWs, were ingested in the cells within 30 min. Treatment with inhibitors of actin polymerization abolished IL-12 secretion in response to ICW stimulation and diminished ingestion of ICWs. When overall shapes of ICWs of L. plantarum were physically disrupted, the disrupted ICWs (DCWs) failed to induce IL-12 secretion. However, DCWs and soluble WTAs inhibited ICW-mediated IL-12 secretion from macrophages. Taken together, these results show that WTA-displaying ICWs of L. plantarum can elicit IL-12 production from macrophages via actin-dependent phagocytosis but TLR2 signaling axis independent pathway. WTAs displayed on ICWs are key molecules in the elicitation of IL-12 secretion, and the sizes and shapes of the ICWs have an impact on actin remodeling and subsequent IL-12 production.

Critical roles of a housekeeping sortase of probiotic Bifidobacterium bifidum in bacterium-host cell crosstalk

Bifidobacterium bifidum YIT 10347 (BF-1) is adhesive in vitro. Here we studied the molecular aspects of the BF-1 adhesion process. We identified and characterized non-adhesive mutants and found that a class E housekeeping sortase was critical for the adhesion to mucin. These mutants were significantly less adhesive to GCIY cells than was the wild type (WT), which protected GCIY cells against acid treatment more than did a non-adhesive mutant. The non-adhesive mutants aberrantly accumulated precursors of putative sortase-dependent proteins (SDPs). Recombinant SDPs bound to mucin. Disruption of the housekeeping sortase influenced expression of SDPs and pilus components. Mutants defective in a pilin or in an SDP showed the same adhesion properties as WT. Therefore, multiple SDPs and pili seem to work cooperatively to achieve adhesion, and the housekeeping sortase is responsible for cell wall anchoring of its substrates to ensure their proper biological function.

Development of an orally-administrable tumor vasculature-targeting therapeutic using annexin A1-binding D-peptides

We previously reported that IF7 peptide, which binds to the annexin A1 (ANXA1) N-terminus, functions as a tumor vasculature-targeted drug delivery vehicle after intravenous injection. To enhance IF7 stability in vivo, we undertook mirror-image peptide phage display using a synthetic D-peptide representing the ANXA1 N-terminus as target. We then identified peptide sequences, synthesized them as D-amino acids, and designated the resulting peptide dTIT7, which we showed bound to the ANXA1 N-terminus. Whole body imaging of mouse brain tumor models injected with near infrared fluorescent IRDye-conjugated dTIT7 showed fluorescent signals in brain and kidney. Furthermore, orally-administered dTIT7/geldanamycin (GA) conjugates suppressed brain tumor growth. Ours is a proof-of-concept experiment showing that ANXA1-binding D-peptide can be developed as an orally-administrable tumor vasculature-targeted therapeutic.

Direct visualization of the extracellular binding structure of E-cadherins in liquid

E-cadherin is a key Ca-dependent cell adhesion molecule, which is expressed on many cell surfaces and involved in cell morphogenesis, embryonic development, EMT, etc. The fusion protein E-cad-Fc consists of the extracellular domain of E-cadherin and the IgG Fc domain. On plates coated with this chimeric protein, ES/iPS cells are cultivated particularly well and induced to differentiate. The cells adhere to the plate via E-cad-Fc in the presence of Ca²⁺ and detach by a chelating agent. For the purpose of clarifying the structures of E-cad-Fc in the presence and absence of Ca²⁺, we analyzed the molecular structure of E-cad-Fc by AFM in liquid. Our AFM observations revealed a rod-like structure of the entire extracellular domain of E-cad-Fc in the presence of Ca²⁺ as well as trans-binding of E-cad-Fc with adjacent molecules, which may be the first, direct confirmation of trans-dimerization of E-cadherin. The observed structures were in good agreement with an X-ray crystallographic model. Furthermore, we succeeded in visualizing the changes in the rod-like structure of the EC domains with and without calcium. The biomatrix surface plays an important role in cell culture, so the analysis of its structure and function may help promote cell engineering based on cell recognition.

Multisite studies for validation and improvement of a highly efficient culture assay for detection of undifferentiated human pluripotent stem cells intermingled in cell therapy products

BACKGROUND AIMS

The Multisite Evaluation Study on Analytical Methods for Non-Clinical Safety Assessment of Human-Derived Regenerative Medical Products (MEASURE) is a Japanese experimental public-private partnership initiative, which aims to standardize methodology for tumorigenicity evaluation of human pluripotent stem cell (hPSC)-derived cell therapy products (CTPs). Undifferentiated hPSCs possess tumorigenic potential, and thus residual undifferentiated hPSCs are one of the major hazards for the risk of tumor formation from hPSC-derived CTPs. Among currently available assays, a highly efficient culture (HEC) assay is reported to be one of the most sensitive for the detection of residual undifferentiated hPSCs.

METHODS

MEASURE first validated the detection sensitivity of HEC assay and then investigated the feasibility of magnetic-activated cell sorting (MACS) to improve sensitivity.

RESULTS

The multisite experiments confirmed that the lower limit of detection under various conditions to which the human induced pluripotent stem cell lines and culture medium/substrate were subjected was 0.001%. In addition, MACS concentrated cells expressing undifferentiated cell markers and consequently achieved a detection sensitivity of 0.00002%.

CONCLUSIONS

These results indicate that HEC assay is highly sensitive and robust and that the application of MACS on this assay is a promising tool for further mitigation of the potential tumorigenicity risk of hPSC-derived CTPs.

Overcoming the blood-brain barrier by Annexin A1-binding peptide to target brain tumours

Background

Annexin A1 is expressed specifically on the tumour vasculature surface. Intravenously injected IF7 targets tumour vasculature via annexin A1. We tested the hypothesis that IF7 overcomes the blood–brain barrier and that the intravenously injected IF7C(RR)-SN38 eradicates brain tumours in the mouse.

Methods

(1) A dual-tumour model was generated by inoculating luciferase-expressing melanoma B16 cell line, B16-Luc, into the brain and under the skin of syngeneic C57BL/6 mice. IF7C(RR)-SN38 was injected intravenously daily at 7.0 μmoles/kg and growth of tumours was assessed by chemiluminescence using an IVIS imager. A similar dual-tumour model was generated with the C6-Luc line in immunocompromised SCID mice. (2) IF7C(RR)-SN38 formulated with 10% Solutol HS15 was injected intravenously daily at 2.5 μmoles/kg into two brain tumour mouse models: B16-Luc cells in C57BL/6 mice, and C6-Luc cells in nude mice.

Results

(1) Daily IF7C(RR)-SN38 injection suppressed tumour growth regardless of cell lines or mouse strains. (2) Daily injection of Solutol-formulated IF7C(RR)-SN38 led into complete disappearance of B16-Luc brain tumour in C57BL/6 mice, whereas this did not occur in C6-Luc in nude mice.

Conclusions

IF7C(RR)-SN38 crosses the blood–brain barrier and suppresses growth of brain tumours in mouse models. Solutol HS15-formulated IF7C(RR)-SN38 may have promoted an antitumour immune response.

Postoperative delirium after pharyngolaryngectomy with esophagectomy: a role for ramelteon and suvorexant

BACKGROUND

Postoperative delirium is common after extensive surgery, and is known to be associated with sleeping medications. In this study, we aimed to investigate the relationships between sleeping medications and postoperative delirium after pharyngolaryngectomy with esophagectomy.

METHODS

We performed a retrospective analysis of 65 patients who underwent pharyngolaryngectomy with esophagectomy at Shizuoka Cancer Center Hospital between January 2012 and March 2016. All data were assessed by two psychiatrists, and univariate and multivariate analyses were performed.

RESULTS

Postoperative delirium developed in 9 (13.8%) patients, with most cases (77.8%) occurring between postoperative day (POD) 1 and POD 3. Of the 24 patients taking a minor tranquilizer after surgery, 8 (33.3%) became delirious, but, of the remaining 41 patients taking ramelteon with or without suvorexant, only one (2.4%) became delirious after surgery. Moreover, of the 16 patients taking both ramelteon and suvorexant, no postoperative delirium was observed. Ramelteon with or without suvorexant was significantly associated with a decreased rate of postoperative delirium compared with minor tranquilizer use (p = 0.001). Multivariate analysis confirmed that the use of ramelteon with or without suvorexant was the only significant preventive factor of postoperative delirium (odds ratio 0.060, p = 0.013).

CONCLUSION

The use of ramelteon with or without suvorexant was the only significant preventive factor of postoperative delirium after pharyngolaryngectomy with esophagectomy. However, using minor tranquilizers was associated with postoperative delirium. We recommend ramelteon with or without suvorexant for preventing postoperative delirium after pharyngolaryngectomy with esophagectomy.

Comparison of Salvage Total Pharyngolaryngectomy and Cervical Esophagectomy Between Hypopharyngeal Cancer and Cervical Esophageal Cancer

BACKGROUND

Total pharyngolaryngectomy and cervical esophagectomy (TPLCE) after chemoradiotherapy remains a challenge because of the high rate of complications and few available data on outcomes and safety. The purpose of this study was to evaluate the clinical significance of salvage TPLCE and to compare treatment outcomes between hypopharyngeal cancer and cervical esophageal cancer.

METHODS

Data from 37 consecutive patients who were diagnosed with potentially resectable hypopharyngeal and cervical esophageal cancer after chemoradiotherapy were retrospectively analyzed. The survival and surgical outcomes were investigated between the hypopharyngeal cancer and cervical esophageal cancer groups.

RESULTS

Twenty-six patients were included in hypopharyngeal cancer group and 11 patients were included in cervical esophageal cancer group. The baseline characteristics were balanced between the two groups. Compared to the hypopharyngeal cancer group, the cervical esophageal cancer group had significantly more frequent tracheal-related complications (p < 0.05) and stronger association of distal margin of the cervical esophagus and radiation field with tracheal ischemia after salvage surgery.

CONCLUSIONS

Salvage TPLCE can offer the exclusive chance of prolonged survival. Association of tracheal ischemia with salvage TPLCE was seen more frequently for cervical esophageal cancer. Therefore, the indication for salvage TPLCE must be carefully considered to maintain the balance between curability and safety.

Incidence and risk factors for postoperative delirium after major head and neck cancer surgery

BACKGROUND

Postoperative delirium is a common and serious complication after extensive surgery. This study aimed to investigate the incidence and risk factors for postoperative delirium after major head and neck cancer surgery.

METHODS

A retrospective analysis was performed for 293 patients who underwent major head and neck cancer surgery lasting >6 h at our institution between January 2012 and November 2015. All data were assessed by two psychiatrists. Univariate and multivariate analyses were performed.

RESULTS

Postoperative delirium developed in 50 (17.1%) patients; most cases (84.0%) of postoperative delirium were observed between postoperative day (POD) 1 and POD 3. Multivariate analysis revealed that an age >70 years was the significant risk factor for postoperative delirium incidence after major head and neck cancer surgery; the multivariate hazard ratio was 3.935 (95% confidence interval 1.873-8.265, p < 0.001).

CONCLUSIONS

Most cases of postoperative delirium after major head and neck cancer surgery were observed between POD 1 and POD 3, and a multivariate analysis revealed that an age >70 years was a significant risk factor for postoperative delirium incidence. Clinicians should pay particular attention to the possibility of delirium incidence during the first 3 days after surgery for patients aged >70 years.

Risk factors for complications after pharyngolaryngectomy with total esophagectomy

BACKGROUND

Pharyngolaryngectomy with total esophagectomy (PLTE) is an effective surgical treatment for synchronous or metachronous hypopharyngeal or laryngeal cancer and thoracic esophageal cancer, although it is more invasive than esophagectomy and total pharyngolaryngectomy. The aim of this study was to identify risk factors for complications after PLTE.

METHODS

From November 2002 to December 2014, a total of 8 patients underwent PLTE at the Shizuoka Cancer Center Hospital, Shizuoka, Japan. We investigated the clinicopathological characteristics, surgical procedures, and postoperative complications of these patients.

RESULTS

Of the 8 patients, 5 underwent one-stage PLTE and 3 underwent staged PLTE. There was no mortality in this study. Two cases of tracheal necrosis, two of anastomotic leakage, and one of ileus were observed as postoperative complications. Two patients who underwent one-stage PLTE with standard mediastinal lymph node dissection developed tracheal necrosis and severe anastomotic leakage.

CONCLUSION

One-stage PLTE and standard mediastinal lymph node dissection were identified as the risk factors for severe postoperative complications. Staged PLTE or transhiatal esophagectomy should be considered when PLTE is performed and standard mediastinal lymph node dissection should be avoided when one-stage PLTE is performed with transthoracic esophagectomy.

Design of a Vitronectin-Based Recombinant Protein as a Defined Substrate for Differentiation of Human Pluripotent Stem Cells into Hepatocyte-Like Cells

Maintenance and differentiation of human pluripotent stem cells (hPSCs) usually requires culture on a substrate for cell adhesion. A commonly used substratum is Matrigel purified from Engelbreth—Holm—Swarm sarcoma cells, and consists of a complex mixture of extracellular matrix proteins, proteoglycans, and growth factors. Several studies have successfully induced differentiation of hepatocyte-like cells from hPSCs. However, most of these studies have used Matrigel as a cell adhesion substrate, which is not a defined culture condition. In an attempt to generate a substratum that supports undifferentiated properties and differentiation into hepatic lineage cells, we designed novel substrates consisting of vitronectin fragments fused to the IgG Fc domain. hPSCs adhered to these substrates via interactions between integrins and the RGD (Arg-Gly-Asp) motif, and the cells maintained their undifferentiated phenotypes. Using a previously established differentiation protocol, hPSCs were efficiently differentiated into mesendodermal and hepatic lineage cells on a vitronectin fragment-containing substrate. We found that full-length vitronectin did not support stable cell adhesion during the specification stage. Furthermore, the vitronectin fragment with the minimal RGD-containing domain was sufficient for differentiation of human induced pluripotent stem cells into hepatic lineage cells under completely defined conditions that facilitate the clinical application of cells differentiated from hPSCs.

Daidzein promotes glucose uptake through glucose transporter 4 translocation to plasma membrane in L6 myocytes and improves glucose homeostasis in Type 2 diabetic model mice

Daidzein shows estrogenic, antioxidant and antiandrogenic properties as well as cell cycle regulatory activity. However, the antihyperglycemic effect of daidzein remains to be elucidated. In this study, we investigated the in vitro effect of daidzein on glucose uptake, AMPK phosphorylation and GLUT4 translocation on plasma membrane in L6 myotubes and its in vivo antihyperglycmic effect in obese-diabetic model db/db mice. Daidzein was found to promote glucose uptake, AMPK phosphorylation and GLUT4 translocation by Western blotting analyses in L6 myotubes under a condition of insulin absence. Promotion by daidzein of glucose uptake as well as GLUT4 translocation to plasma membrane by immunocytochemistry was also demonstrated in L6 myoblasts transfected with a GLUT4 cDNA-coding vector. Daidzein (0.1% in the diet) suppressed the rises in the fasting blood glucose, serum total cholesterol levels and homeostasis model assessment index of db/db mice. In addition, daidzein supplementation markedly improved the AMPK phosphorylation in gastrocnemius muscle of db/db mice. Daidzein also suppressed increases in blood glucose levels and urinary glucose excretion in KK-Ay mice, another Type 2 diabetic animal model. These in vitro and in vivo findings suggest that daidzein is preventive for Type 2 diabetes and an antidiabetic phytochemical.

ABCG2 inhibitor YHO-13351 sensitizes cancer stem/initiating-like side population cells to irinotecan

BACKGROUND/AIM

The aim of this study was to determine the efficacy of the combination of irinotecan and newly-synthesized ABCG2 (breast cancer-resistant protein) inhibitor YHO-13351 in cancer chemotherapy.

MATERIALS AND METHODS

Side population (SP) and non-SP cells from the human cervical carcinoma cell line HeLa were isolated by fluorescence-activated cell sorting. The antitumor activity of combination therapy with irinotecan and YHO-13351 was evaluated in xenograft studies in athymic BALB/c nude mice.

RESULTS

While SP cells exhibited cancer stem/initiating cell-like properties and low sensitivity to irinotecan-alone, YHO-13351 sensitized them to irinotecan in both in vitro and in vivo studies. YHO-13351 in conjunction with irinotecan reduced the increase of the SP cell ratio in the tumors compared to those observed with treatment with irinotecan-alone.

CONCLUSION

Combination therapy with irinotecan and YHO-13351 would not only accelerate the antitumor effect of this regimen, but also play a crucial role in preventing resistance or relapse.

JD induced pluripotent stem cell-derived hepatocytes faithfully recapitulate the pathophysiology of familial hypercholesterolemia

Elevated levels of low-density lipoprotein cholesterol (LDL-C) in plasma are a major contributor to cardiovascular disease, which is the leading cause of death worldwide. Genome-wide association studies (GWAS) have identified 95 loci that associate with control of lipid/cholesterol metabolism. Although GWAS results are highly provocative, direct analyses of the contribution of specific allelic variations in regulating LDL-C has been challenging due to the difficulty in accessing appropriate cells from affected patients. The primary cell type responsible for controlling cholesterol and lipid flux is the hepatocyte. Recently, we have shown that cells with hepatocyte characteristics can be generated from human induced pluripotent stem cells (iPSCs). This finding raises the possibility of using patient-specific iPSC-derived hepatocytes to study the functional contribution of GWAS loci in regulating lipid metabolism. To test the validity of this approach, we produced iPSCs from JD a patient with mutations in the low-density lipoprotein receptor (LDLR) gene that result in familial hypercholesterolemia (FH). We demonstrate that (1) hepatocytes can be efficiently generated from FH iPSCs; (2) in contrast to control cells, FH iPSC-derived hepatocytes are deficient in LDL-C uptake; (3) control but not FH iPSC-derived hepatocytes increase LDL uptake in response to lovastatin; and (4) FH iPSC-derived hepatocytes display a marked elevation in secretion of lipidated apolipoprotein B-100.

CONCLUSION

Cumulatively, these findings demonstrate that FH iPSC-derived hepatocytes recapitulate the complex pathophysiology of FH in culture. These results also establish that patient-specific iPSC-derived hepatocytes could be used to definitively determine the functional contribution of allelic variation in regulating lipid and cholesterol metabolism and could potentially provide a platform for the identification of novel treatments of cardiovascular disease. (HEPATOLOGY 2012).

Bacterial production of the tunicate-derived antitumor cyclic depsipeptide didemnin B

Natural products obtained from marine invertebrates such as sponges and tunicates are attractive sources of drugs. However, a critical obstacle in the development of these compounds is the problem of supply. In most cases, neither chemical synthesis nor mariculture of invertebrates is economically feasible. Due to structural similarities, many marine natural products are suspected to be produced by associated microorganisms. A favorable strategy for the production of such compounds is to use culturable microorganisms. Here we report that didemnin B, a tunicate-derived depsipeptide, has been isolated from a culturable bacterium, Tistrella mobilis YIT 12409.

HNF4A is essential for specification of hepatic progenitors from human pluripotent stem cells

The availability of pluripotent stem cells offers the possibility of using such cells to model hepatic disease and development. With this in mind, we previously established a protocol that facilitates the differentiation of both human embryonic stem cells and induced pluripotent stem cells into cells that share many characteristics with hepatocytes. The use of highly defined culture conditions and the avoidance of feeder cells or embryoid bodies allowed synchronous and reproducible differentiation to occur. The differentiation towards a hepatocyte-like fate appeared to recapitulate many of the developmental stages normally associated with the formation of hepatocytes in vivo. In the current study, we addressed the feasibility of using human pluripotent stem cells to probe the molecular mechanisms underlying human hepatocyte differentiation. We demonstrate (1) that human embryonic stem cells express a number of mRNAs that characterize each stage in the differentiation process, (2) that gene expression can be efficiently depleted throughout the differentiation time course using shRNAs expressed from lentiviruses and (3) that the nuclear hormone receptor HNF4A is essential for specification of human hepatic progenitor cells by establishing the expression of the network of transcription factors that controls the onset of hepatocyte cell fate.

Transcriptional control of hepatocyte differentiation

The liver is the largest glandular organ in the body and plays a central role in controlling metabolism. During hepatogenesis, complex developmental processes must generate an array of cell types that are spatially arranged to generate a hepatic architecture that is essential to support liver function. The processes that control the ultimate formation of the liver are diverse and complex and in many cases poorly defined. Much of the focus of research during the past three decades has been on understanding how hepatocytes, which are the predominant liver parenchymal cells, differentiate during embryogenesis. Through a combination of mouse molecular genetics, embryology, and molecular biochemistry, investigators have defined a myriad of transcription factors that combine to control formation and function of hepatocytes. Here, we will review the major discoveries that underlie our current understanding of transcriptional regulation of hepatocyte differentiation.

Gait balance disorder by thalamic infarction with the disorder of interstitial nucleus of cajal

The interstitial nucleus of Cajal (INC) is thought to play an important role in torsional/vertical eye position and head posture, and disorders of the INC induce abnormal ocular movements and head tilt. Our patients with ocular tilt reactions simultaneously also had disturbances in ambulatory balance, yet no reports address the loss of balance control induced by disorders of the INC. We examined the ambulatory disturbances induced by INC lesion. We experienced three patients with ocular movement disorders and abnormal head tilt due to thalamic infarction. We performed ophthalmic examinations on and checked the balance of them. With funduscopy, abnormal cycloduction was seen in the unaffected side and normal cycloduction was observed in the affected side. Nevertheless, Hess charts showed distortions in the visual image of both eyes. They all had disorders of balance control. We tried to treat them using the Bobath approach for improving their ambulatory balance. With subsequent improvements in balance control it was possible for them to take short walks, but it was difficult to make any improvements in their ocular movement. The INC is related to balance control of ambulation and disorders of the INC induce ambulatory disturbances. Cycloduction was only observed in the unaffected side, but Hess charts showed distortions of the visual image in both eyes. Ambulation was briefly improved, but diplopia persisted in these patients.

Design, Synthesis, and Antitumor Activity of 4-Halocolchicines and Their Pro-drugs Activated by Cathepsin B

Novel colchicine derivatives possessing various substituents at the C4 position were prepared. Among them, 4-halo derivatives 3-6 were found to exhibit higher activity against cancer cell lines (A549, HT29, HCT116) as well as on mice transplanted with the HCT116 human colorectal carcinoma cell line than colchicine (1). Further, utilizing the 4-substituted colchicines, we prepared pro-drugs having a dipeptide side chain and demonstrated that these pro-drugs were activated by cathepsin B, an enzyme overexpressed in tumor cells, and exhibited selective toxicity to the tumor cells.

The effect of recombinant E-cadherin substratum on the differentiation of endoderm-derived hepatocyte-like cells from embryonic stem cells

Generation of specific lineages of cells from embryonic stem (ES) cells is pre-requisite to use these cells in pre-clinical applications. Here, we developed a recombinant E-cadherin substratum for generation of hepatic progenitor populations at single cell level. This artificial acellular feeder layer supports the stepwise differentiation of ES cells to cells with characteristics of definitive endoderm, hepatic progenitor cells, and finally cells with phenotypic and functional characteristics of hepatocytes. The efficient differentiation of hepatic endoderm cells (approximately 55%) together with the absence of neuroectoderm and mesoderm markers suggests the selective induction of endoderm differentiation. The co-expression of E-cahderin and alpha-fetoprotein (approximately 98%) suggests the important role of E-cadherin as a surface marker for the enrichment of hepatic progenitor cells. With extensive expansion, approximately 92% albumin expressing cells can be achieved without any enzymatic stress and cell sorting. Furthermore, these mouse ES cell-derived hepatocyte-like cells showed higher morphological similarities to primary hepatocytes. In conclusion, we demonstrated that E-cadherin substratum can guide differentiation of ES cells into endoderm-derived hepatocyte-like cells. This recombinant extracellular matrix could be effectively used as an in vitro model for studying the mechanisms of early stages of liver development even at single cell level.

Culture of human pluripotent stem cells using completely defined conditions on a recombinant E-cadherin substratum

Background

To maintain pluripotency of human embryonic stem (huES) cells in feeder-free culture it has been necessary to provide a Matrigel substratum, which is a complex of poorly defined extracellular matrices and growth factors derived from mouse Engelbreth-Holm-Swarm sarcoma cells. Culture of stem cells under ill-defined conditions can inhibit the effectiveness of maintaining cells in a pluripotent state and reduce reproducibility of differentiation protocols. Moreover recent batches of Matrigel have been found to be contaminated with the single stranded RNA virus, Lactate Dehydrogenase Elevating Virus (LDEV), raising concerns regarding the safety of using stem cells that have been cultured on Matrigel in a therapeutic setting. To circumvent such concerns, we attempted to identify a recombinant matrix that could be used as an alternative to Matrigel for the culture of human pluripotent stem cells. huES and human induced pluripotent stem (hiPS) cells were grown on plates coated with a fusion protein consisting of E-cadherin and the IgG Fc domain using mTeSR1 medium.

Results

Cells grown under these conditions maintained similar morphology and growth rate to those grown on Matrigel and retained all pluripotent stem cell features, including an ability to differentiate into multiple cell lineages in teratoma assays. We, therefore, present a culture system that maintains the pluripotency of huES and hiPS cells under completely defined conditions.

Conclusions

We propose that this system should facilitate growth of stem cells using good manufacturing practices (GMP), which will be necessary for the clinical use of pluripotent stem cells and their derivatives.

Bacterial teichoic acids reverse predominant IL-12 production induced by certain lactobacillus strains into predominant IL-10 production via TLR2-dependent ERK activation in macrophages

The cytokine response of macrophages to probiotic lactobacilli varies between strains, and the balance of IL-10/IL-12 production is crucial for determination of the direction of the immune response. To clarify the mechanism whereby Lactobacillus strains differentially induce production of IL-10 and IL-12, we examined the potential relationship between cytokine production and MAPK activation. In mouse peritoneal macrophages, Lactobacillus plantarum potently induced IL-10 but weakly induced IL-12 production, whereas L. casei potently induced IL-12 but weakly induced IL-10 production. Kinetic analysis of the activation of ERK, p38, and JNK showed that L. plantarum induced a more rapid and intense activation of MAPKs, especially of ERK, than L. casei. A selective blockade of ERK activation induced by L. plantarum resulted in a decrease in IL-10 production and a simultaneous increase in IL-12 production. Interestingly, when macrophages were stimulated with a combination of L. plantarum and L. casei, IL-10 production was induced synergistically. We identified cell wall teichoic acid and lipoteichoic acid as key factors for triggering the synergistic induction of IL-10 production, although these teichoic acids alone only weakly induced IL-10 production. The effect of these teichoic acids on IL-10 production was mediated by TLR2-dependent ERK activation. Our data demonstrate that activation of the ERK pathway is critical for determination of the balance of the IL-10/IL-12 response of macrophages to lactobacilli and that predominant IL-12 production induced by certain lactobacilli such as L. casei can be converted into predominant IL-10 production when stimulated in the presence of teichoic acids.

Artificial extracellular matrix for embryonic stem cell cultures: a new frontier of nanobiomaterials

Nanobiomaterials can play a central role in regenerative medicine and tissue engineering by facilitating cellular behavior and function, such as those where extracellular matrices (ECMs) direct embryonic stem (ES) cell morphogenesis, proliferation, differentiation and apoptosis. However, controlling ES cell proliferation and differentiation using matrices from natural sources is still challenging due to complex and heterogeneous culture conditions. Moreover, the systemic investigation of the regulation of self-renewal and differentiation to lineage specific cells depends on the use of defined and stress-free culture conditions. Both goals can be achieved by the development of biomaterial design targeting ECM or growth factors for ES cell culture. This targeted application will benefit from expansion of ES cells for transplantation, as well as the production of a specific differentiated cell type either by controlling the differentiation in a very specific pathway or by elimination of undesirable cell types.

Peptidoglycan from lactobacilli inhibits interleukin-12 production by macrophages induced by Lactobacillus casei through Toll-like receptor 2-dependent and independent mechanisms

We previously showed that Lactobacillus strains having a rigid cell wall resistant to intracellular digestion can stimulate macrophages to induce large a quantity of interleukin-12 (IL-12). In this study, we examined the influence of lactobacilli and bacterial cell wall components on IL-12 production by macrophages that was induced by Lactobacillus casei, which has a rigid cell wall. Easily digestible lactobacilli such as Lactobacillus johnsonii and Lactobacillus plantarum or their intact cell walls (ICWs) weakly or very weakly induced IL-12 production by macrophages, and inhibitedL. casei-induced IL-12 production. While the ICW of L. casei was resistant to intracellular digestion and did not inhibit L. casei-induced IL-12 production, its polysaccharide-depleted ICW, i.e. intact peptidoglycan, was sensitive to intracellular digestion and inhibited L. casei-induced IL-12 production. Furthermore, the peptidoglycans of L. johnsonii, L. plantarum and Staphylococcus aureus also inhibited L. casei-induced IL-12 production. Peptidoglycans from lactobacilli suppressed L. casei-induced expression of IL-12p40 but not IL-12p35 mRNA. Inhibition of IL-12 production by peptidoglycan was mitigated in Toll-like receptor 2 (TLR2)-deficient macrophages compared with the inhibition in wild-type macrophages. A derivative of the minimal structural unit of peptidoglycan (6-O-stearoyl-muramyl dipeptide) recognized by nucleotide-binding oligomerization domain 2 (NOD2) could also suppress L. casei-induced IL-12 production. These findings demonstrate that easily digestible bacteria and peptidoglycan suppress IL-12 production through pattern recognition receptors such as TLR2 and NOD2. IL-12 production in the gut may be negatively regulated by the simultaneous inhibitory actions of various resident bacteria that are susceptible to intracellular digestion.

Highly efficient generation of human hepatocyte-like cells from induced pluripotent stem cells

There exists a worldwide shortage of donor livers available for orthotropic liver transplantation and hepatocyte transplantation therapies. In addition to their therapeutic potential, primary human hepatocytes facilitate the study of molecular and genetic aspects of human hepatic disease and development and provide a platform for drug toxicity screens and identification of novel pharmaceuticals with potential to treat a wide array of metabolic diseases. The demand for human hepatocytes, therefore, heavily outweighs their availability. As an alternative to using donor livers as a source of primary hepatocytes, we explored the possibility of generating patient-specific human hepatocytes from induced pluripotent stem (iPS) cells.

CONCLUSION

We demonstrate that mouse iPS cells retain full potential for fetal liver development and describe a procedure that facilitates the efficient generation of highly differentiated human hepatocyte-like cells from iPS cells that display key liver functions and can integrate into the hepatic parenchyma in vivo.