The tumor immune microenvironment (TIME) is one of the significant hallmarks of cancer and has the important role of largely determining the malignancy level of tumors. As an approach to break through this bottleneck of tumor treatment methods, the TIME can be reprogrammed by certain nanomaterials. Here, we coated C-novyi-spores with melittin-RADA₃₂ nanofiber hybrid peptide and loaded the immunomodulator metformin to obtain MRM-coated spores as a powerful antitumor nanodrug against glioblastoma (GBM), which is based on the activation of the TIME. MRM-coated spores exhibit extended-release profiles and an enhanced killing effect on GBM both in vitro and in vivo. Furthermore, MRM-coated spores can educate the innate and adaptive immune system by inducing sustainable CD8⁺ T cell responses, promoting M1 macrophage polarization, and regulating the expression of HIF1-α, PDL1, and CXCL9 in TIME. In intracranial applications, MRM-coated spores showed excellent biosafety and a strong therapeutic effect. In summary, peptide hydrogels provide a promising strategy in which advantages of different treatment methods can be incorporated to synthesize potent antitumor drugs with mild side effects from bacteria-mediated nanomaterials.

True bone ceramic (TBC), obtained by twice sintering fresh bovine cancellous bone at high temperatures, is an osteoconductive and bioactive bone substitute material that exhibits excellent biocompatibility with hard tissue. The authors have previously synthesized a novel BMP-2-related peptide, P24, and found that it could enhance the osteoblastic differentiation of cells. The objective of the present study was to construct a double-modified TBC via mineralization into simulated body fluid and P24 incorporation for enhanced bone formation. In vitro experiments revealed that surface mineralization-modified (SMM) TBC scaffolds demonstrated efficiency for sustained release of P24. The P24/SMM-TBC composite exhibited increased osteogenic activity by cell adhesion rate determination, MTT assay, alkaline phosphatase staining, and calcium nodule staining with alizarin red compared with SMM-TBC and TBC. In vivo studies showed that the P24/SMM-TBC composite scaffold promoted significant bone defect repair, in marked contrast to stand-alone SMM-TBC and TBC, based on the results of radiographic evaluation and histological examination. These findings indicate that SMM-TBC is a good scaffold for the controlled release of P24 and that the P24/SMM-TBC composite could improve the adhesion, proliferation and differentiation of cells and repair bone defects. The double-modified P24/SMM-TBC composite biomaterial shows potential for clinical application in bone tissue engineering.

Emerging evidence highlights the crucial role of gastrointestinal microbiota in the pathogenesis of gastric cancer. Helicobacter pylori (H. pylori) infection stands out as a primary pathogenic factor. However, interventions such as anti-H. pylori therapy, gastric surgeries, immunotherapy, and chronic inflammation significantly remodel the gastric microbiome, implicating a broader spectrum of microorganisms in cancer development. These microbial populations can modulate gastric carcinogenesis through various mechanisms, including sustained chronic inflammation, bacterial genotoxins, alterations in short-chain fatty acids, elevated gastrointestinal bile acids, impaired mucus barrier function, and increased concentrations of N-nitrosamines and lactic acid. The dynamic changes in gut microbiota also critically influence the outcomes of anti-cancer therapies by modifying drug bioavailability and metabolism, thus affecting therapeutic efficacy and side effect profiles. Additionally, the effectiveness of radiotherapy can be significantly impacted by gut microbiota alterations. Novel therapeutic strategies targeting the microbiome, such as dietary interventions, probiotic and synbiotic supplementation, and fecal microbiota transplantation, are showing promise in cancer treatment. Understanding the intricate relationship between the gut microbiota and gastric cancer is essential for developing new, evidence-based approaches to the prevention and treatment of this malignancy.