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Pre-harvest sprouting (PHS) is a complex trait controlled by multiple genes with strong interaction between environment and genotype that makes it difficult to select breeding materials by phenotypic assessment. One of the most important genes for pre-harvest sprouting resistance is consistently identified on the long arm of chromosome 4A. The 4AL PHS tolerance gene has therefore been targeted by Australian white-grained wheat breeders. A new robust PCR marker for the PHS QTL on wheat chromosome 4AL based on candidate genes search was developed in this study. The new marker was mapped on 4AL deletion bin 13-0.59-0.66 using 4AL deletion lines derived from Chinese Spring. This marker is located on 4AL between molecular markers Xbarc170 and Xwg622 in the doubled-haploid wheat population Cranbrook × Halberd. It was mapped between molecular markers Xbarc170 and Xgwm269 that have been previously shown to be closely linked to grain dormancy in the doubled haploid wheat population SW95-50213 × Cunningham and was co-located with Xgwm269 in population Janz × AUS1408. This marker offers an additional efficient tool for marker-assisted selection of dormancy for white-grained wheat breeding. Comparative analysis indicated that the wheat chromosome 4AL QTL for seed dormancy and PHS resistance is homologous with the barley QTL on chromosome 5HL controlling seed dormancy and PHS resistance. This marker will facilitate identification of the gene associated with the 4A QTL that controls a major component of grain dormancy and PHS resistance. [ABSTRACT FROM AUTHOR]

The surface marker CD44 has been identified as one of several markers associated with cancer stem cells (CSC) in solid tumors, but its ubiquitous expression in many cell types, including hematopoietic cells, has hindered its use in targeting CSCs. In this study, 28 paired primary tumor and adjacent nontumor gastric tissue samples were analyzed for cell surface protein expression. Cells that expressed pan-CD44 were found to occur at significantly higher frequency in gastric tumor tissues. We identified CD44v8-10 as the predominant CD44 variant expressed in gastric cancer cells and verified its role as a gastric CSC marker by limiting dilution and serial transplantation assays. Parallel experiments using CD133 failed to enrich for gastric CSCs. Analyses of another 26 primary samples showed significant CD44v8-10 upregulation in gastric tumor sites. Exogenous expression of CD44v8-10 but not CD44 standard (CD44s) increased the frequency of tumor initiation in immunocompromised mice. Reciprocal silencing of total CD44 resulted in reduced tumor-initiating potential of gastric cancer cells that could be rescued by CD44v8-10 but not CD44s expression. Our findings provide important functional evidence that CD44v8-10 marks human gastric CSCs and contributes to tumor initiation, possibly through enhancing oxidative stress defense. In addition, we showed that CD44v8-10 expression is low in normal tissues. Because CD44 also marks CSCs of numerous human cancers, many of which may also overexpress CD44v8-10, CD44v8-10 may provide an avenue to target CSCs in other human cancers. [ABSTRACT FROM AUTHOR]

Background: Biomarkers such as quantitative HBsAg (qHBsAg), quantitative hepatitis B virus (HBV) core-related antigen (qHBcrAg) and HBV RNA may be useful in predicting HBsAg loss in patients with chronic hepatitis B (CHB) undergoing antiviral therapy., Aim(s): Our study evaluated qHBsAg, HBV RNA and qHBcrAg as a posthoc analysis of a randomized clinical trial of peginterferon±NA to determine their utility in predicting HBsAg loss., Methods: CHB patients who completed therapy with 48weeks peginterferon alpha2b ± nucleoside analogue therapy (clinicaltrial.gov NCT01928511) were evaluated at week 72 for HBsAg loss. The predictive ability of qHBsAg, qHBcrAg, HBV RNA and other variables were investigated by univariate and multivariate logistic models for HBeAg-negative patients by odds ratios, area under the curve (AUC), sensitivity, specificity, and positive and negative likelihood ratios (LR)., Results: HBsAg loss occurred in 15/114(13%) HBeAg-negative CHB patients who completed 48 weeks of peginterferon. At baseline, qHBsAg was superior to HBcrAg and HBV RNA with AUC 0.916, 0.649 and 0.542, respectively. Using multivariate analysis, the model comprising treatmentarm, age, gender, baseline qHBsAg, HBcrAg and HBV RNA, weeks 4 & 8 qHBsAg had the highest AUC(0.98), but the univariate model with week 8 qHBsAg <70 IU/mL had AUC 0.96. Hence, the contributions of variables other than qHBsAg were marginal. HBV RNA and qHBcrAg were weak predictors of HBsAg loss. Kinetics of the novel markers showed only qHBsAg had a good relationship with HBsAg loss while HBV RNA had a marginal relationship and HBcrAg did not change at all, and none had a good relationship with viral rebound., Conclusions: On-treatment biomarker predictors were better than baseline ones, and the best predictor of HBsAg loss at 72 weeks was week 8 qHBsAg <70 IU/mL., (© 2020 John Wiley & Sons Ltd.)