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1.
J Dent Res ; 97(6): 725-732, 2018 06.
Article in English | MEDLINE | ID: mdl-29630846

ABSTRACT

Results from microbiome studies on oral cancer have been inconsistent, probably because they focused on compositional analysis, which does not account for functional redundancy among oral bacteria. Based on functional prediction, a recent study revealed enrichment of inflammatory bacterial attributes in oral squamous cell carcinoma (OSCC). Given the high relevance of this finding to carcinogenesis, we aimed here to corroborate them in a case-control study involving 25 OSCC cases and 27 fibroepithelial polyp (FEP) controls from Sri Lanka. DNA extracted from fresh biopsies was sequenced for the V1 to V3 region with Illumina's 2 × 300-bp chemistry. High-quality nonchimeric merged reads were classified to the species level with a prioritized BLASTN-based algorithm. Downstream compositional analysis was performed with QIIME (Quantitative Insights into Microbial Ecology) and linear discriminant analysis effect size, while PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) was utilized for bacteriome functional prediction. The OSCC tissues tended to have lower species richness and diversity. Genera Capnocytophaga, Pseudomonas, and Atopobium were overrepresented in OSCC, while Lautropia, Staphylococcus, and Propionibacterium were the most abundant in FEP. At the species level, Campylobacter concisus, Prevotella salivae, Prevotella loeschii, and Fusobacterium oral taxon 204 were enriched in OSCC, while Streptococcus mitis, Streptococcus oral taxon 070, Lautropia mirabilis, and Rothia dentocariosa among others were more abundant in FEP. Functionally, proinflammatory bacterial attributes, including lipopolysaccharide biosynthesis and peptidases, were enriched in the OSCC tissues. Thus, while the results in terms of species composition significantly differed from the original study, they were consistent at the functional level, substantiating evidence for the inflammatory nature of the bacteriome associated with OSCC.


Subject(s)
Carcinoma, Squamous Cell/microbiology , Microbiota , Mouth Neoplasms/microbiology , Polyps/microbiology , Carcinoma, Squamous Cell/etiology , Case-Control Studies , DNA, Bacterial/genetics , Dysbiosis/complications , Dysbiosis/microbiology , Humans , Inflammation/microbiology , Male , Microbiota/genetics , Middle Aged , Mouth Neoplasms/etiology , RNA, Ribosomal, 16S/genetics , Sequence Analysis, DNA
2.
Int J Oncol ; 42(6): 1911-8, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23563899

ABSTRACT

Immunotoxins are engineered chimeric proteins that consist of a fragment of a toxin fused to a modified antibody or growth factor capable of targeting specific cells. Furthermore, these proteins can be targeted to receptors that are commonly overexpressed on cancer cells. The majority of immunotoxins function by binding to cells, translocating into the cytosol and inhibiting protein synthesis. In this study, the expression of claudin­4 (CLDN4) in various cancer cells was analysed as a potential target for immunotoxins. To target CLDN4-expressing cancer cells, the c-terminal CLDN4­binding domain of Clostridium perfringens enterotoxin (CPE) was fused to the Pseudomonas aeruginosa exotoxin A (ETA) domain to create an immunotoxin (CPE­ETA'). Subsequently, the capacity of such an immunotoxin in suppressing the proliferation of CLDN4-positive cancer cells was investigated. We report that head and neck squamous carcinoma cells (HN5) have an elevated CLDN4 expression compared to the other cell lines tested. Our findings further demonstrate that CPE­ETA' is highly potent against MCF-7 breast [50% inhibitory concentration (IC50) 9.8 ng/ml] and HN5 head/neck (IC50 8.8 ng/ml) cancer cell lines, while it has no cytotoxic effects on HeLa cells (CLDN4­negative). The immunotoxin was subsequently expressed in the tumour colonising oncolytic strain, Clostridium ghonii. Most importantly, the strictly anaerobic Clostridium ghonii was able to overexpress and secrete a functional CPE­ETA' fusion protein. Our findings open the possibility of the targeted delivery of the immunotoxin locally to tumour sites at a high concentration using strictly anaerobic Clostridium ghonii for the treatment of CLDN4-positive cancer cells.


Subject(s)
Antineoplastic Agents/pharmacology , Claudin-4/metabolism , Immunotoxins/genetics , Immunotoxins/pharmacology , ADP Ribose Transferases/genetics , ADP Ribose Transferases/metabolism , Antineoplastic Agents/immunology , Bacterial Toxins/genetics , Bacterial Toxins/metabolism , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Carcinoma, Squamous Cell/drug therapy , Carcinoma, Squamous Cell/metabolism , Carcinoma, Squamous Cell/pathology , Cell Line, Tumor , Cell Proliferation/drug effects , Clostridium/genetics , Enterotoxins/genetics , Exotoxins/genetics , Exotoxins/metabolism , Female , HeLa Cells , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/metabolism , Head and Neck Neoplasms/pathology , Humans , Inhibitory Concentration 50 , Molecular Targeted Therapy/methods , Recombinant Fusion Proteins/immunology , Recombinant Fusion Proteins/isolation & purification , Recombinant Fusion Proteins/pharmacology , Virulence Factors/genetics , Virulence Factors/metabolism , Pseudomonas aeruginosa Exotoxin A
3.
Pediatr Infect Dis J ; 20(2): 127-33, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11224828

ABSTRACT

BACKGROUND: Oral oseltamivir administration is effective treatment for influenza in adults. This study was conducted to determine the efficacy, safety and tolerability of oseltamivir in children with influenza. METHODS: In this randomized, double blind, placebo-controlled study, children 1 through 12 years with fever [> or =100 degrees F (> or =38 degrees C)] and a history of cough or coryza <48 h duration received oseltamivir 2 mg/kg/dose or placebo twice daily for 5 days. The primary efficacy endpoint was the time to resolution of illness including mild/absent cough and coryza mild/absent, return to normal activity and euthermia. RESULTS: Of 695 enrolled children 452 (65%) had influenza (placebo, n = 235; oseltamivir, n = 217). Among infected children the median duration of illness was reduced by 36 h (26%) in oseltamivir compared with placebo recipients (101 h; 95% confidence interval, 89 to 118 vs. 137 h; 95% confidence interval, 125 to 150; P < 0.0001). Oseltamivir treatment also reduced cough, coryza and duration of fever. New diagnoses of otitis media were reduced by 44% (12% vs. 21%). The incidence of physician-prescribed antibiotics was significantly lower in influenza-infected oseltamivir (68 of 217, 31%) than placebo (97 of 235, 41%; P = 0.03) recipients. Oseltamivir therapy was generally well-tolerated, although associated with an excess frequency of emesis (5.8%). Discontinuation because of adverse events was low in both groups (1.8% with oseltamivir vs. 1.1% with placebo). Oseltamivir treatment did not affect the influenza-specific antibody response. CONCLUSIONS: Oral oseltamivir administration is an efficacious and well-tolerated therapy for influenza in children when given within 48 h of onset of illness.


Subject(s)
Acetamides/therapeutic use , Antiviral Agents/therapeutic use , Influenza, Human/drug therapy , Acetamides/administration & dosage , Administration, Oral , Antiviral Agents/administration & dosage , Child , Child, Preschool , Cough , Double-Blind Method , Female , Humans , Infant , Influenza, Human/complications , Influenza, Human/physiopathology , Male , Oseltamivir , Safety , Time Factors , Treatment Outcome
4.
Antivir Ther ; 5(3): 205-13, 2000 Sep.
Article in English | MEDLINE | ID: mdl-11075941

ABSTRACT

Oseltamivir is the prodrug of Ro64-0802 (GS4071), a potent and selective inhibitor of influenza A and B virus neuraminidases. Three randomized, double-blind, placebo-controlled, parallel-group studies evaluated oral oseltamivir for early treatment (75 or 150 mg twice daily for 5 days) or prevention (75 mg once or twice daily for 7 days) of experimental influenza B virus infection in healthy susceptible adults. Treatment study A (n=60) demonstrated similar trends to treatment study B (n=117), in which 75 mg doses of oseltamivir introduced 24 h after inoculation reduced median area under curve (AUC) virus titre (oseltamivir, 22.7; placebo, 131.1 log10 TCID50 x h/ml; P=0.002) and duration of viral shedding (oseltamivir, 23.9 h; placebo, 95.8 h; P=0.0005). In prevention study C (n=58), oseltamivir did not reduce infection rates (85 versus 84%) but significantly reduced median AUC virus titre (10.0 versus 66.9 log10 TCID50 x h/ml; P=0.03) and duration of viral shedding (36 versus 84 h; P=0.03) compared with placebo. Oseltamivir was well tolerated. No emergence of drug-resistant variants was detected by testing last-day isolates (n=112) in neuraminidase inhibition assays. These results indicate that oseltamivir has significant antiviral activity in experimental human influenza B virus infection when used for prophylaxis or early treatment.


Subject(s)
Acetamides/therapeutic use , Antiviral Agents/therapeutic use , Influenza B virus , Influenza, Human/drug therapy , Influenza, Human/prevention & control , Adolescent , Adult , Double-Blind Method , Humans , Influenza B virus/isolation & purification , Influenza B virus/pathogenicity , Influenza, Human/virology , Middle Aged , Oseltamivir
5.
Transplantation ; 66(4): 507-15, 1998 Aug 27.
Article in English | MEDLINE | ID: mdl-9734496

ABSTRACT

BACKGROUND: After heart transplantation, 1-year and 5-year survival rates are 79% and 63%, respectively, with rejection, infection, and allograft coronary artery disease accounting for the majority of deaths. Mycophenolate mofetil (MMF), an inhibitor of the de novo pathway for purine biosynthesis, decreases rejection in animals and in human renal transplantation. METHODS: In a double-blind, active-controlled trial, 28 centers randomized 650 patients undergoing their first heart transplant to receive MMF (3000 mg/day) or azathioprine (1.5-3 mg/kg/day), in addition to cyclosporine and corticosteroids. Rejection and survival data were obtained for 6 and 12 months, respectively. Because 11% of the patients withdrew before receiving study drug, data were analyzed on all randomized patients (enrolled patients) and on patients who received study medications (treated patients). RESULTS: Survival and rejection were similar in enrolled patients (MMF, n=327; azathioprine, n=323). In treated patients (MMF, n=289; azathioprine, n=289), the MMF group compared with the azathioprine group was associated with significant reduction in mortality at 1 year (18 [6.2%] versus 33 deaths [11.4%]; P=0.031) and a significant reduction in the requirement for rejection treatment (65.7% versus 73.7%; P=0.026). There was a trend for fewer MMF patients to have > or = grade 3A rejection (45.0% versus 52.9%; P=0.055) or require the murine monoclonal anti-CD3 antibody or antithymocyte globulin (15.2% versus 21.1%; P=0.061). Opportunistic infections, mostly herpes simplex, were more common in the MMF group (53.3% versus 43.6%; P=0.025). CONCLUSIONS: Substitution of MMF for azathioprine may reduce mortality and rejection in the first year after cardiac transplantation.


Subject(s)
Azathioprine/therapeutic use , Graft Rejection/prevention & control , Heart Transplantation , Immunosuppressive Agents/therapeutic use , Mycophenolic Acid/analogs & derivatives , Aged , Coronary Angiography , Double-Blind Method , Female , Graft Rejection/epidemiology , Heart Transplantation/diagnostic imaging , Heart Transplantation/mortality , Humans , Male , Middle Aged , Mycophenolic Acid/therapeutic use , Prospective Studies , Survival Rate , Ultrasonography
6.
Am J Gastroenterol ; 89(7): 1014-20, 1994 Jul.
Article in English | MEDLINE | ID: mdl-8017358

ABSTRACT

OBJECTIVE: Conventional ulcer therapy has not been proven effective in healing gastric ulcers caused by nonsteroidal anti-inflammatory drugs (NSAIDs) if the NSAIDs are continued. Our objective in this study was to determine whether a prostaglandin analog is an effective treatment for such NSAID-induced lesions. METHODS: To make this determination, we conducted a 9-wk double-blind trial comparing placebo with enprostil 35 micrograms twice daily and three times daily. Use of antacids was not allowed. Three centers entered 145 patients with chronic inflammatory arthritis and osteoarthritis, mean age 63 yr, who required continuous fixed-dose NSAID therapy within the range of therapeutic dosage. The minimum entrance criterion was the presence of either four gastric erosions or one gastric ulcer. Two pretreatment endoscopies within a 2-wk interval were performed to establish the presence of stable baseline gastric lesions. Endoscopy was repeated at wk 6 and 9 during treatment. All groups were similar with regard to age distribution, sex, weight, height, smoking usage, and alcohol consumption. RESULTS: The ulcer healing rates were 14%, 57%, and 68% at 6 wk and 19%, 68%, and 74% at 9 wk for the groups receiving placebo, enprostil twice daily, and enprostil three times daily, respectively (p < 0.01). Complete mucosal healing of all erosions and ulcers at 9 wk occurred in 59% of enprostil-treated patients and in 10% of placebo-treated patients. Additional gastric erosions and gastric ulcers developed in 16% of placebo patients and 4% of the enprostil patients. Eighteen percent of enprostil patients withdrew early from the study due to adverse experiences, such as diarrhea and abdominal pain. CONCLUSION: We concluded that during continued NSAID therapy 1) enprostil 35 micrograms (taken either twice daily or three times daily) heals NSAID-induced gastric ulcers and erosions and protects the mucosa from further NSAID-induced gastric injury; 2) gastric ulcers and erosions rarely heal spontaneously, and 3) enprostil results in a high incidence of diarrhea.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/adverse effects , Enprostil/therapeutic use , Stomach Ulcer/chemically induced , Stomach Ulcer/drug therapy , Aged , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Arthritis, Rheumatoid/drug therapy , Double-Blind Method , Enprostil/adverse effects , Female , Gastric Mucosa/pathology , Humans , Male , Middle Aged , Osteoarthritis/drug therapy , Stomach Ulcer/pathology
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