Protein Expression of Programmed Death 1 Ligand 1 and HER2 in Gastric Carcinoma.

OBJECTIVES: Programmed death 1 (PD-1) is an immunoinhibitory receptor and has been identified as a new target for immunotherapy in cancer. Here we report the expression of PD-1 ligand 1 (PD-L1) in surgically resected gastric cancer. MATERIALS AND METHODS: We examined formalin-fixed tumor samples from 144 gastric cancer patients with a primary diagnosis of gastric carcinoma. Immunohistochemistry was used to detect PD-L1. Human epidermal growth factor receptor 2 (HER2) expression and phosphatase and tensin homolog (PTEN) loss of heterozygosity were investigated in these patients. RNA interference was used to downregulate HER2 expression, and PD-L1 protein expression was assessed by flow cytometry using the gastric cancer cell line MKN45. RESULTS: Overexpression of PD-L1 was significantly correlated with tumor invasion (p = 0.011) and associated with poor survival. The number of PD-L1-positive cases increased according to the HER2 score in clinical samples. siRNA-mediated downregulation of HER2 significantly decreased PD-L1 protein expression in MKN45 cells. CONCLUSIONS: PD-L1 expression was associated with poor survival of gastric cancer, and HER2 signaling affects the expression of PD-L1 in gastric cancer. In gastric cancer, PTEN and HER2 are potential candidate biomarkers for developing human antibodies that block PD-L1.

Neutrophil-lymphocyte ratio reflects hepatocellular carcinoma recurrence after liver transplantation via inflammatory microenvironment.

BACKGROUND & AIMS: Although the Milan criteria (MC) have been used to select liver transplantation candidates among patients with hepatocellular carcinoma (HCC), many patients exceeding the MC have shown good prognosis. Preoperative neutrophil-lymphocyte ratio (NLR) is a predictor of patient prognosis, but its mechanism has never been clarified. METHODS: We assessed outcomes in 158 patients who had undergone living-donor liver transplantation (LDLT) for HCC. Recurrence-free survival (RFS) was determined in patients with high (≥ 4) and low (<4) NLR. Levels of expression of vascular endothelial growth factor (VEGF), interleukin (IL)-8, IL-17, CD68, and CD163 were measured. RESULTS: The 5-year RFS rate was significantly lower in patients with high (n=26) than with low (n=132) NLR (30.3% vs. 89.0%, p<0.0001), in patients with high (n=15) than with low (n=79) NLR who met the MC (73.6% vs. 100%, p=0.0008) and in patients with high (n=11) than with low (n=53) NLR who exceeded the MC (0% vs. 76.1%, p=0.0002). Tumor expression of VEGF, IL8, IL-17, CD68, and CD163 was similar in the high and low NLR groups, but serum and peritumoral IL-17 levels were significantly higher in the high-NLR group (p=0.01 each). The density of peritumoral CD163 correlated with the density of peritumoral IL-17-producing cells (p=0.04) and was significantly higher in the high-NLR group (p=0.005). CONCLUSIONS: NLR predicts outcomes after LDLT for HCC via the inflammatory tumor microenvironment. Combined with the MC, NLR may be a new criterion for LDLT candidates with HCC.

A mechanical analysis of femoral resurfacing implantation for osteonecrosis of the femoral head.

Hip resurfacing is becoming a popular procedure for treating osteonecrosis of the femoral head. However, the biomechanical changes that occur after femoral resurfacing have not been fully investigated with respect to the individual extent of the necrosis. In this study, we evaluated biomechanical changes at various extents of necrosis and implant alignments using the finite element analysis method. We established 3 patterns of necrosis by depth from the surface of femoral head and 5 stem angles. For these models, we evaluated biomechanical changes associated with the extent of necrosis and the stem alignment. Our results indicate that stress distribution near the bone-cement interface increased with expansion of the necrosis. The maximum stress on the prosthesis was decreased with stem angles ranging from 130° to 140°. The peak stress of cement increased as the stem angle became varus. This study indicates that resurfacing arthroplasty will have adverse biomechanical effects when there is a large extent of osteonecrosis and excessive varus or valgus implantation of the prosthesis.

Glutathione S-transferase A1 polymorphism as a risk factor for smoking-related type 2 diabetes among Japanese.

Glutathione S-transferases protect cells against exogenous and endogenous oxidative stress. Type 2 diabetes is associated with an increased production of reactive oxygen species and a reduction in antioxidant defenses. This study investigated whether GSTA1*A/*B and GSTP1Ile105Val polymorphisms could affect the risk for type 2 diabetes. A cross-sectional case-control analysis included 468 (326 men and 142 women) Japanese participants in a health screening program. The prevalence of type 2 diabetes was 11.3% (63 subjects: 52 male and 11 female). The frequency of GSTA1*B allele carriers was higher in diabetes than in non-diabetes, though the difference was not statistically significant (adjusted OR, 1.8; 95% CI, 0.9-3.4). The risk among the GSTA1*B allele carriers was significantly increased by current-smoking status (adjusted OR, 3.7; 95% CI, 1.1-12.7; vs. never-smoking non-carriers), whereas the smoking status was not an independent risk factor. The GSTP1 genotype alone or in combination with the smoking status did not affect the risk for diabetes. This is the first report to show that the GSTA1*B allele is a potential risk factor for smoking-related type 2 diabetes.

PD-L1 Is Upregulated by Simultaneous Amplification of the PD-L1 and JAK2 Genes in Non-Small Cell Lung Cancer.

OBJECTIVES: The programmed death ligand 1(PD-L1)/programmed cell death protein 1 (PD-1) pathway is one of the most important checkpoint pathways for mediating tumor-induced immune suppression through T-cell exhaustion. Recently, targeted therapies using monoclonal antibodies against components of this pathway have been shown to reduce tumor burden in patients with non-small cell lung cancer (NSCLC). However, the prognostic significance of PD-L1 expression is controversial and the precise mechanisms of PD-L1 gene activation in lung cancer have yet to be clarified. METHODS: We investigated copy number alterations (CNAs) in the PD-L1 gene by real-time PCR in 94 surgically resected lung cancer samples to find possible associations between PD-L1 CNA and lung cancer biology. Janus kinase 2 gene (JAK2) CNA and its influence on the PD-L1/PD-1 pathway were also assessed. RESULTS: Five samples were shown to have PD-L1 gene amplification, whereas 89 samples did not. The patients with PD-L1 amplification had worse prognoses than did those without PD-L1 amplification. Genetic amplification of the PD-L1 gene was correlated with JAK2 gene amplification. The lung cancer cell line HCC4006 was found to harbor both JAK2 and PD-L1 amplification. Flow cytometry analyses revealed the level of PD-L1 protein expression to be higher in HCC4006 cells than in other NSCLC cell lines. Expression of the PD-L1 protein was significantly reduced by the JAK2 inhibitor TG-101348 and the signal transducer and activator of transcription 3 (STAT-3) inhibitor BP-1-102, but not by the STAT1 inhibitor fludarabine. CONCLUSIONS: Our data suggest that expression of PD-L1 protein is upregulated by the simultaneous amplification of the PD-L1 and JAK2 genes through JAK-STAT signaling in NCSLC.

A herbal-drug interaction study of keishi-bukuryo-gan, a traditional herbal preparation used for menopausal symptoms, in healthy female volunteers.

OBJECTIVES: Many patients use herbal medicines to relieve menopausal symptoms. Keishi-bukuryo-gan contains five herbal components, and has been used for treating hypermenorrhoea, dysmenorrhoea and menopausal symptoms in Asian countries. In this study, we investigated the potential herb-drug interactions of keishi-bukuryo-gan in healthy female subjects. METHODS: Thirty-one healthy females (20-27 years) were studied to evaluate their baseline activity of cytochrome P450 (CYP) 1A2, CYP2D6, CYP3A, xanthine oxidase (XO) and N-acetyltransferase 2 (NAT2) based on the urinary metabolic indices of an 8-h urine sample collected after a 150-mg dose of caffeine and a 30-mg dose of dextromethorphan, and also the urinary excretion ratio of 6ß-hydroxycortisol to cortisol. Thereafter, the subjects received 3.75g of keishi-bukuryo-gan twice daily for seven days, and underwent the same tests on post-dose day 7. KEY FINDINGS: The geometric mean phenotypic index for CYP1A2 significantly decreased by 16% on day 7 compared with the baseline (P=0.026). Keishi-bukuryo-gan did not alter the indices for CYP2D6, CYP3A, XO and NAT2. CONCLUSIONS: Keishi-bukuryo-gan may inhibit the activity of CYP1A2, which is predominantly involved in oestrogen metabolism. However, TJ-25 is unlikely to participate in herb-drug interactions involving medications predominantly metabolized by CYP2D6, CYP3A, XO and NAT2. K

Association between cytochrome P450 3A5 polymorphism and the lung function in Saskatchewan grain workers.

OBJECTIVE: The activity of the enzymes that metabolize tobacco smoke may affect the susceptibility to chronic obstructive pulmonary disease (COPD). Cytochrome P450 (CYP) 3A5 is expressed selectively over CYP3A4 in human lung, but the association between the CYP3A5 polymorphisms and the airway injury is unknown. METHODS: Two hundred and six male Saskatchewan grain workers participated in this longitudinal study, and their lung function values of forced expiratory volume in the first second (FEV1) and forced vital capacity (FVC), respiratory symptoms, smoking status, and the occupational history were analyzed. RESULTS: A significant interactive effect was observed between the CYP3A5 genotype and current smoking status on FEV1, and the annual decline rates of FEV1 and FVC in current smokers were greater among CYP3A5*1/*3 carriers than CYP3A5*3/*3 carriers (-48.7+/-16.4 vs. -31.5+/-4.7 ml/years, P=0.02; -27.4+/-18.9 vs. -5.8+/-6.5 ml/years, P=0.04). The incidences of chronic cough and COPD were also higher in current smokers with CYP3A5*1/*3 than in nonsmokers and current smokers with CYP3A5*3/*3. The adjusted odds ratios for chronic cough and COPD current smokers with CYP3A5*1/*3 versus nonsmokers with the CYP3A5*3/*3 genotype were 11.4 (P=0.009) and 4.3 (P=0.13), respectively. CONCLUSION: The results suggest that CYP3A5*1 may be a novel genetic risk factor for airway injury in smokers, and that CYP3A5 may play a role in airway injury owing to the bioactivation of chemicals in tobacco smoke.