GSH/pH Cascade-Responsive Nanoparticles Eliminate Methicillin-Resistant Staphylococcus aureus Biofilm via Synergistic Photo-Chemo Therapy.

Bacterial biofilm infection threatens public health, and efficient treatment strategies are urgently required. Phototherapy is a potential candidate, but it is limited because of the off-targeting property, vulnerable activity, and normal tissue damage. Herein, cascade-responsive nanoparticles (NPs) with a synergistic effect of phototherapy and chemotherapy are proposed for targeted elimination of biofilms. The NPs are fabricated by encapsulating IR780 in a polycarbonate-based polymer that contains disulfide bonds in the main chain and a Schiff-base bond connecting vancomycin (Van) pendants in the side chain (denoted as SP-Van@IR780 NPs). SP-Van@IR780 NPs specifically target bacterial biofilms in vitro and in vivo by the mediation of Van pendants. Subsequently, SP-Van@IR780 NPs are decomposed into small size and achieve deep biofilm penetration due to the cleavage of disulfide bonds in the presence of GSH. Thereafter, Van is then detached from the NPs because the Schiff base bonds are broken at low pH when SP@IR780 NPs penetrate into the interior of biofilm. The released Van and IR780 exhibit a robust synergistic effect of chemotherapy and phototherapy, strongly eliminate the biofilm both in vitro and in vivo. Therefore, these biocompatible SP-Van@IR780 NPs provide a new outlook for the therapy of bacterial biofilm infection.

Dual-Cascade Responsive Nanoparticles Enhance Pancreatic Cancer Therapy by Eliminating Tumor-Resident Intracellular Bacteria.

The limited drug penetration and robust bacteria-mediated drug inactivation in pancreatic cancer result in the failure of chemotherapy. To fight against these issues, a dual-cascade responsive nanoparticle (sNP@G/IR) that can sequentially trigger deep penetration, killing of intratumor bacteria, and controlled release of chemo-drug, is reported. sNP@G/IR consists of a hyaluronic acid (HA) shell and glutathione (GSH)-responsive polymer-core (NP@G/IR), that encapsulates gemcitabine (Gem) and photothermal agent (IR1048). The polymer core, as an antibiotic alternative, is tailored to exert optimal antibacterial activity and selectivity. sNP@G/IR actively homes in on the tumor due to the CD44 targeting of the HA shell, which is subsequently degraded by the hyaluronidase in the extracellular matrix. The resultant NP@G/IR in decreased size and reversed charge facilitates deep tumor penetration. After cellular endocytosis, the exposed guanidine on NP@G/IR kills intracellular bacteria through disrupting cell membranes. Intracellular GSH further triggers the controlled release of the cargo. Thus, the protected Gem eventually induces cell apoptosis. Under laser irradiation, the hyperthermia of IR1048 helps further elimination of tumors and bacteria. Moreover, sNP@G/IR activates immune response, thereby reinforcing anticancer capacity. Therefore, this dual-cascade responsive sNP@G/IR eliminates tumor-resident intracellular bacteria and augments drug delivery efficacy, providing a new avenue for improving cancer therapy.

An immune-related model based on INHBA, JAG2 and CCL19 to predict the prognoses of colon cancer patients.

BACKGROUND: Colorectal cancer (CRC) is the leading cause of cancer deaths and most common malignant tumors worldwide. Immune-related genes (IRGs) can predict prognoses of patients and the effects of immunotherapy. A series of colon cancer (CCa) samples from The Cancer Genome Atlas (TCGA) were analyzed to provide a new perspective into this field. METHODS: Differential IRGs and IRGs with significant clinical outcomes (sIRGs) were calculated by the limma algorithm and univariate COX regression analysis. The potential molecular mechanisms of IRGs were detected by PPI, KEGG and GO analysis. Immune-related risk score model (IRRSM) was established based on multivariate COX regression analysis. Based on the median risk score of IRRSM, the high-risk group and low-risk group were distinguished. The expression levels of IHNBA and JAG2 and relationships between IHNBA and clinical features were verified by RT-qPCR. RESULTS: 6 differential sIRGs of patients with CCa were selected by univariate COX regression analysis. Based on the sIRGs (INHBA, JAG2 and CCL19), the IRRSM was established to predict survival probability of CCa patients and to explore the potential correlations with clinical features. Furthermore, IRRSM reflected the infiltration status of 22 types of immune cells. The expression levels of IHNBA and JAG2 were higher in CCa tissues than that in adjacent normal tissues. The expression levels of IHNBA and JAG2 were increased in advanced T stages. CONCLUSION: Our results illustrated that some sIRGs showed the latent value of predicting the prognoses of CCa patients and the clinical features. This study could provide a new insight for immune research and treatment strategies in CCa patients.