Background APETALA2/ETHYLENE RESPONSIVE FACTOR (AP2/ERF) transcription factors play essential roles in plant growth, development, metabolism, and responses to biotic and abiotic stresses. However, few studies concerning AP2/ERF genes in sugarcane which are the most critical sugar and energy crops worldwide. Results A total of 218 AP2/ERF genes were identified in the Saccharum spontaneum genome. Phylogenetic analysis showed that these genes could be divided into four groups, including 43 AP2s, 160 ERFs and Dehydration-responsive element-binding (DREB) factors, 11 ABI3/VPs (RAV), and four Soloist genes. These genes were unevenly distributed on 32 chromosomes. The structural analysis of SsAP2/ERF genes showed that 91 SsAP2/ERFs lacked introns. Sugarcane and sorghum had a collinear relationship between 168 SsAP2/ERF genes and sorghum AP2/ERF genes that reflected their similarity. Multiple cis-regulatory elements (CREs) present in the SsAP2/ERF promoter were related to abiotic stresses, suggesting that SsAP2/ERF activity could contribute to sugarcane adaptation to environmental changes. The tissue-specific analysis showed spatiotemporal expression of SsAP2/ERF in the stems and leaves of sugarcane at different development stages. In ten sugarcane samples, 39 SsAP2/ERFs were not expressed, whereas 58 SsAP2/ERFs were expressed in all samples. Quantitative PCR experiments showed that SsERF52 expression was up-regulated under salt stress, but suppressed under dehydration stress. SsSoloist4 had the most considerable upregulation in response to treatment with the exogenous hormones ABA and GA. Within 3 h of ABA or PEG6000 treatment, SsSoloist4 expression was up-regulated, indicating that this gene could play a role in the responses to ABA and GA-associated dehydration stress. Analysis of AP2/ERF gene expression patterns under different treatments indicated that SsAP2/ERF genes played an essential role in dehydration and salt stress responses of S. spontaneum. Conclusions In this study, a total of 218 members of the AP2 / ERF superfamily were identified in sugarcane, and their genetic structure, evolution characteristics, and expression patterns were studied and analyzed. The results of this study provide a foundation for future analyses to elucidate the importance of AP2/ERF transcription factors in the function and molecular breeding of sugarcane.

Background Breast cancer is one of the most common malignancies threatening women’s health. Triple-negative breast cancer (TNBC) is a special type of breast cancer with high invasion and metastasis. CXCL12 and its receptors CXCR4 and CXCR7 play a crucial role in the progress of breast cancer. The aim of this study was to investigate the effect of CXCR4 and CXCR7 on the function of TNBC. Materials and methods We used the CRISPR/Cas9 technique to carry out a single knockout of the CXCR4 or CXCR7 gene and co-knockout of CXCR4 and CXCR7 genes in the TNBC cell line (MDA-MB-231). The single knockout and co-knockout cells were screened and verified by PCR sequencing and Western blot assay, the effect of single knockout and co-knockout on the proliferation of TNBC cells was examined using the Cell Counting Kit-8 and colony formation assays, the migration and invasion of TNBC cells were examined by the transwell and wound-healing assays, the changes in the cell cycle distribution after knockout were detected by flow cytometry, and the difference in the migration and invasion of single knockout and co-knockout induced by CXCL12 was observed by adding CXCL12 in the experimental group. Results The single knockout of the CXCR4 or CXCR7 gene significantly reduced the cell proliferation, growth, migration, and invasion and delayed the conversion of the G1/S cycle, while the co-knockout inhibited these biological abilities more significantly. In both the knockout and control groups, the migration and invasion of CXCL12-added cells were significantly stronger than those of the non-CXCL12-added cells, and CXCL12 induced lesser migration and invasion in the CXCR4 and CXCR7 co-knockout group than in the single knockout groups. Conclusion The knockout of the CXCR4 and CXCR7 genes affects the binding capacity and functions of CXCL12, inhibits the malignant progression of TNBC cells significantly, and may become a potential target for the treatment of TNBC.

Background: Association between metabolic syndrome (MetS) and incidence of breast cancer remains to be validated. Moreover, whether menopausal status of the women affects this association is unclear. A meta-analysis was performed to summarize the association between MetS and breast cancer risk.Methods: Follow-up studies were identified by search of PubMed and Embase databases published until May 26, 2019. A random-effect model or fixed-effect model was applied to pool the results according to the heterogeneity. Subgroup analyses according to the menopausal status, ethnic groups, cancer histopathological features, and study design characteristics.Results: Overall, 17 follow-up studies with 602,195 women and 15,945 cases of breast cancer were included. Results of meta-analysis showed that MetS defined by the revised National Cholesterol Education Program's Adults Treatment Panel III criteria was associated with significantly increased risk for breast cancer incidence (adjusted risk ratio [RR] = 1.15, p = 0.003). Subgroup analyses showed that MetS was associated with significantly increased risk of breast cancer in postmenopausal women (adjusted RR = 1.25, p < 0.001), but significantly reduced breast cancer risk in premenopausal women (adjusted RR = 0.82, p < 0.001). Further analyses showed that the association between MetS and increased risk of breast cancer were mainly evidenced from studies including Caucasian and Asian women, reporting invasive breast cancer, and of retrospective design.Conclusions: Menopausal status may affect the association between MetS and breast cancer incidence. Postmenopausal women with Mets are associated with increased risk of breast cancer.

Background: Metabolic syndrome (MetS) has been suggested to be a risk factor for many cancers, including breast cancer. However, it remains unclear whether MetS predicts poor prognosis in women with breast cancer. A meta-analysis was performed to summarize the association between MetS and clinical outcome in women with breast cancer. Methods: Cohort studies were identified by search of PubMed and Embase databases. A random-effect model incorporating the potential heterogeneity was applied to pool the results. Subgroup analyses according to the ethnicity and study design were performed. Results: Nine cohort studies with 17,892 women with breast cancer were included. Pooled results showed that MetS was significantly associated with an increased risk of breast cancer recurrence (adjusted risk ratio [RR] = 1.52, 95%, p = 0.02). Subgroup analyses showed that MetS was independently associated with increased recurrence of breast cancer in Caucasians (adjusted RR = 1.75, p = 0.02), but not in Asians (adjusted RR = 1.07, p = 0.81), and MetS was associated with a trend of increased risk of breast cancer recurrence in both the prospective and retrospective studies. Although we failed to show a significant association between MetS and breast cancer related deaths (adjusted RR = 1.24, p = 0.41), MetS was associated with increased risk of all-cause deaths in these patients (adjusted RR = 1.80, p < 0.001). Conclusions: MetS may predict the risk of cancer recurrence and mortality in women with breast cancer, particularly in Caucasians.

Drought is the main abiotic stress that constrains sugarcane growth and production. To understand the molecular mechanisms that govern drought stress, we performed a comprehensive comparative analysis of physiological changes and transcriptome dynamics related to drought stress of highly drought-resistant (ROC22, cultivated genotype) and weakly drought-resistant (Badila, wild genotype) sugarcane, in a time-course experiment (0 h, 4 h, 8 h, 16 h and 32 h). Physiological examination reviewed that ROC22, which shows superior drought tolerance relative to Badila, has high performance photosynthesis and better anti-oxidation defenses under drought conditions. The time series dataset enabled the identification of important hubs and connections of gene expression networks. We identified 36,956 differentially expressed genes (DEGs) in response to drought stress. Of these, 15,871 DEGs were shared by the two genotypes, and 16,662 and 4423 DEGs were unique to ROC22 and Badila, respectively. Abscisic acid (ABA)-activated signaling pathway, response to water deprivation, response to salt stress and photosynthesis-related processes showed significant enrichment in the two genotypes under drought stress. At 4 h of drought stress, ROC22 had earlier stress signal transduction and specific up-regulation of the processes response to ABA, L-proline biosynthesis and MAPK signaling pathway–plant than Badila. WGCNA analysis used to compile a gene regulatory network for ROC22 and Badila leaves exposed to drought stress revealed important candidate genes, including several classical transcription factors: NAC87, JAMYB, bHLH84, NAC21/22, HOX24 and MYB102, which are related to some antioxidants and trehalose, and other genes. These results provide new insights and resources for future research and cultivation of drought-tolerant sugarcane varieties.