Background Aberrant changes in epigenetic mechanisms such as histone modifications play an important role in cancer progression. PRMT1 which triggers asymmetric dimethylation of histone H4 on arginine 3 (H4R3me2a) is upregulated in human colorectal cancer (CRC) and is essential for cell proliferation. However, how this dysregulated modification might contribute to malignant transitions of CRC remains poorly understood. Methods In this study, we integrated biochemical assays including protein interaction studies and chromatin immunoprecipitation (ChIP), cellular analysis including cell viability, proliferation, colony formation, and migration assays, clinical sample analysis, microarray experiments, and ChIP-Seq data to investigate the potential genomic recognition pattern of H4R3me2s in CRC cells and its effect on CRC progression. Results We show that PRMT1 and SMARCA4, an ATPase subunit of the SWI/SNF chromatin remodeling complex, act cooperatively to promote colorectal cancer (CRC) progression. We find that SMARCA4 is a novel effector molecule of PRMT1-mediated H4R3me2a. Mechanistically, we show that H4R3me2a directly recruited SMARCA4 to promote the proliferative, colony-formative, and migratory abilities of CRC cells by enhancing EGFR signaling. We found that EGFR and TNS4 were major direct downstream transcriptional targets of PRMT1 and SMARCA4 in colon cells, and acted in a PRMT1 methyltransferase activity-dependent manner to promote CRC cell proliferation. In vivo, knockdown or inhibition of PRMT1 profoundly attenuated the growth of CRC cells in the C57BL/6 J-ApcMin/+ CRC mice model. Importantly, elevated expression of PRMT1 or SMARCA4 in CRC patients were positively correlated with expression of EGFR and TNS4, and CRC patients had shorter overall survival. These findings reveal a critical interplay between epigenetic and transcriptional control during CRC progression, suggesting that SMARCA4 is a novel key epigenetic modulator of CRC. Our findings thus highlight PRMT1/SMARCA4 inhibition as a potential therapeutic intervention strategy for CRC. Conclusion PRMT1-mediated H4R3me2a recruits SMARCA4, which promotes colorectal cancer progression by enhancing EGFR signaling.

With the aim of improving the solubility of ciprofloxacin, polybasic organic acids were utilized to react with ciprofloxacin in different stoichiometric proportions. The use of the solvent drop grinding (SDG) method, as well as the solvent evaporation method, resulted in the crystalline salts ciprofloxacin/fumaric acid (1:1, 2:1), ciprofloxacin/maleic acid (1:1) and ciprofloxacin/citric acid (2:1). The solubilities of these salts in pure water (pH 7.0) were determined using high-performance liquid chromatography (HPLC) at 310 K, with the salts showing considerably greater solubility than ciprofloxacin itself and, interestingly, ciprofloxacin/fumaric acid (2:1) being more soluble than ciprofloxacin/fumaric acid (1:1). Intrigued by this phenomenon, we undertook a comparison of the crystal structures of the salts: the three-dimensional sandwich-like structure observed in the 2:1 salt indicates that the preferred stacking may be a factor in increasing the solubility of ciprofloxacin.

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The Ti implants with XPEED(®) surfaces significantly enhanced apatite formation, removal torque value, and the BIC%. The Ti implants with XPEED(®) surfaces may induce strong bone integration by improving osseointegration of grit-blasted Ti implants in areas of poor quality bone.

BBC is a drug with a variety of activities but poor solubility. Cocrystal technology is an effective method to improve the solubility and stability of this type of compound. In this work, the cocrystal of BBC with fumaric acid was obtained at a stoichiometric ratio of 2:1. Studies on stabilities and solubilities were carried out using BBC dihydrate and tetrahydrate as reference materials. Results showed that this new cocrystal did not only significantly improve the dissolution rate of BBC but also highly improved the stability in high humidity and temperature. Given that the cocrystals formed by BBC as the host molecule were few, different techniques were applied for characterization and structural analyses. Moreover, theoretical calculations were performed on weak interactions, such as hydrogen bonding and π–π stacking interactions, which provided the research data for the study of this kind of cocrystal.