Prevention of postoperative pneumonia by perioperative oral care in patients with esophageal cancer undergoing surgery: a multicenter retrospective study of 775 patients.

PURPOSE: Postoperative pneumonia is one of the major complications after esophageal cancer surgery. The risk factors associated with postoperative pneumonia are poor general health, smoking, decreased pulmonary function, diabetes mellitus, surgical stress, old age, postoperative aspiration, and oral hygiene. In this study, we examined the effect of perioperative oral care on reducing postoperative pneumonia since the evidence to-date is not clear. METHODS: A multicenter, retrospective investigation of the relationship between perioperative oral care and incidence of postoperative pneumonia in patients undergoing esophageal cancer surgery was conducted. A total of 775 patients who underwent thoracoscopic esophageal resection at 25 hospitals between 2016 and 2017 were enrolled in the study. Various factors were examined for correlation with development of postoperative pneumonia. RESULTS: Multivariate analysis showed that old age, smoking habit, lower hemoglobin, higher creatinine, postoperative dysphagia, and lack of oral care intervention were independent risk factors for pneumonia. Oral care was more effective in preventing pneumonia in hospitals in which the incidence of postoperative pneumonia was lower than 20%, while it was not effective in hospitals in which the incidence was higher than 20%. CONCLUSION: Results of the study suggest that it is recommended to carry out perioperative oral care in esophageal cancer surgery.

Multicenter phase II study of an oral care program for patients with head and neck cancer receiving chemoradiotherapy.

PURPOSE: This multicenter phase II trial assessed the clinical benefit of a multidisciplinary oral care program in reducing the incidence of severe chemoradiotherapy-induced oral mucositis (OM). METHODS: Patients with head and neck cancer (HNC) who were scheduled to receive definitive or postoperative chemoradiotherapy were enrolled. The oral care program included routine oral screening by dentists and a leaflet containing instructions regarding oral care, nutrition, and lifestyle. Oral hygiene and oral care were evaluated continuously during and after the course of chemoradiotherapy. The primary endpoint was the incidence of grade ≥3 OM assessed by certified medical staff according to the Common Terminology Criteria of Adverse Events version 3.0. RESULTS: From April 2012 to December 2013, 120 patients with HNC were enrolled. Sixty-four patients (53.3 %) developed grade ≥3 OM (i.e., functional/symptomatic). The incidence of grade ≤1 OM at 2 and 4 weeks after radiotherapy completion was 34.2 and 67.6 %, respectively. Clinical examination revealed that 51 patients (42.5 %) developed grade ≥3 OM during chemoradiotherapy. The incidence of grade ≤1 OM at 2 and 4 weeks after radiotherapy completion was 54.7 and 89.2 %, respectively. The incidences of grade 3 infection and pneumonitis throughout chemoradiotherapy were <5 %. Only 6.7 % of patients had unplanned breaks in radiotherapy, and 99.2 % completed treatment. CONCLUSIONS: A systematic oral care program alone is insufficient to decrease the incidence of severe OM in patients with HNC being treated with chemoradiotherapy. However, systematic oral care programs may indirectly improve treatment compliance by decreasing infection risk. TRIAL REGISTRATION NUMBER: UMIN000006660.

Factors secreted from dental pulp stem cells show multifaceted benefits for treating experimental rheumatoid arthritis.

Rheumatoid arthritis (RA) is an autoimmune disease characterized by synovial hyperplasia and chronic inflammation, which lead to the progressive destruction of cartilage and bone in the joints. Numerous studies have reported that administrations of various types of MSCs improve arthritis symptoms in animal models, by paracrine mechanisms. However, the therapeutic effects of the secreted factors alone, without the cell graft, have been uncertain. Here, we show that a single intravenous administration of serum-free conditioned medium (CM) from human deciduous dental pulp stem cells (SHED-CM) into anti-collagen type II antibody-induced arthritis (CAIA), a mouse model of rheumatoid arthritis (RA), markedly improved the arthritis symptoms and joint destruction. The therapeutic efficacy of SHED-CM was associated with an induction of anti-inflammatory M2 macrophages in the CAIA joints and the abrogation of RANKL expression. SHED-CM specifically depleted of an M2 macrophage inducer, the secreted ectodomain of sialic acid-binding Ig-like lectin-9 (ED-Siglec-9), exhibited a reduced ability to induce M2-related gene expression and attenuate CAIA. SHED-CM also inhibited the RANKL-induced osteoclastogenesis in vitro. Collectively, our findings suggest that SHED-CM provides multifaceted therapeutic effects for treating CAIA, including the ED-Siglec-9-dependent induction of M2 macrophage polarization and inhibition of osteoclastogenesis. Thus, SHED-CM may represent a novel anti-inflammatory and reparative therapy for RA.

Dental pulp-derived stem cell conditioned medium reduces cardiac injury following ischemia-reperfusion.

Stem cells from human exfoliated deciduous teeth (SHEDs) can regenerate various tissues. We investigated the impact of SHED-conditioned medium (SHED-CM) on myocardial injury in a mouse model of ischemia-reperfusion (I/R). Wild-type (WT) mice were subjected to myocardial ischemia followed by reperfusion. SHED-CM was intravenously injected at 5 min after reperfusion. Administration of SHED-CM reduced myocardial infarct size as well as decreased apoptosis and inflammatory cytokine levels, such as TNF-α, IL-6, and IL-ß, in the myocardium following I/R. In cultured cardiac myocytes, SHED-CM significantly suppressed apoptosis under hypoxia/serum-deprivation and reduced LPS-induced expression of pro-inflammatory genes. Furthermore, anti-apoptotic action of SHED-CM was stronger than bone marrow-derived stem cell (BMSC)-CM or adipose-derived stem cell (ADSC)-CM in cardiac myocytes. SHED-CM contains a higher concentration of hepatocyte growth factor (HGF) than BMSC-CM and ADSC-CM, and neutralization of HGF attenuated the inhibitory actions of SHED-CM on apoptosis in cardiac myocytes. Finally, WT mice were intravenously treated with an HGF-depleted SHED-CM, followed by myocardial I/R. HGF depletion significantly attenuated the inhibitory actions of SHED-CM on myocardial infarct size and apoptosis after I/R. SHED-CM protects the heart from acute ischemic injury because it suppresses inflammation and apoptosis. SHED-CM could be a useful treatment option for acute myocardial infarction.

Improvement of transduction efficiency of recombinant adenovirus vector conjugated with cationic liposome for human oral squamous cell carcinoma cell lines.

Adenovirus (Ad) vectors are commonly used in gene therapy trials because of their efficiency in gene transfer. However, their use is limited by immune responses that reduce transgene expression and decrease the efficiency of repeated vector administration. In this study, the efficacy of gene transduction and the tumor-cell killing effect on four human oral (SAS, HSC-2, HSC-3, HSC-4) and one murine squamous cell carcinoma cell (SCC-7, a kind gift of Dr. M. Hiraoka, Kyoto University) lines in vitro with Ad vector conjugated with catioic liposome (Ad/SUV) was evaluated. Ad/SUV resulted in two to five-fold over higher transduction efficiency in four human and one murine cell lines in vitro than Ad vector alone. The optimal Ad-SUV ratio was determined as 10(6) pfu of Ad vector with 1 micromol SUV. Ad/SUV showed more tumor-cell killing effect than Ad vector alone. Furthermore, the shielding effects of Ad vector with Ad/SUV from neutralizing antibody were evaluated. We also found that Ad/SUV is less susceptible to inactivation by neutralizing antibodies in vitro. The efficacy of gene transduction with Ad vector was blocked more than 70% with neutralizing serum, while Ad/SUV retained approximately 50% of the control activity in vitro. On the basis of these results, the anti-tumor effect with suicide gene therapy using Ad/SUV in vivo was evaluated. Three injections of Ad/SUV showed the inhibition of tumor growth compared with control in vivo. Our results suggested that an enhanced anti-tumor effect on human oral squamous cell carcinoma would be obtained with repeated administrations of Ad/SUV.

Cell death of human oral squamous cell carcinoma cell line induced by herpes simplex virus thymidine kinase gene and ganciclovir.

Suicide gene therapy combining herpes simplex virus thymidine kinase gene (HSVtk) and ganciclovir (GCV) is one strategy for the treatment of head and neck squamous cell carcinoma (HNSCC). The purpose of this study is to determine the mechanism of cell death that occurs in suicide gene therapy using HSVtk and GCV and to assess the safety of that therapy. The human oral squamous cell carcinoma cell line SAS was treated with adenovirus vector containing HSVtk gene (AdHSVtk) and GCV in vitro. Morphological changes including chromatin condensation, cell shrinkage, blebbing of cell membrane, and ballooning formations were observed. Changes in the localization of phospholipids in the cell membrane were also observed. The results of flow cytometry showed a maximum of about 65% of cells in the early phase of apoptosis. In addition, DNA fragmentation was investigated using the TUNEL method in vivo. Nude mice (BALB/c AJD(-nu-), aged 4 weeks) were implanted with SAS and treated with AdHSVtk and GCV. Tumor sections were then observed. The treatment group was confirmed to have DNA fragmentation-positive cells. These results suggest that suicide gene therapy using AdHSVtk and GCV led to apoptosis of the oral squamous cell carcinoma cell line.