No abstract

Two major challenges of current photodynamic therapy (PDT) are the limited tissue penetration of excitation light and poor tumor-selectivity of the photosensitizer (PS). To address these issues, we developed a multifunctional nanoconstruct consisting of upconversion nanoparticles (UCNPs) that transform near-infrared (NIR) light to visible light and a photosensitizer zinc(II) phthalocyanine (ZnPc). Folate-modified amphiphilic chitosan (FASOC) was coated on the surface of UCNPs to anchor the ZnPc close to the UCNPs, thereby facilitating resonance energy transfer from UCNPs to ZnPc. Confocal microscopy and NIR small animal imaging demonstrated the enhanced tumor-selectivity of the nanoconstructs to cancer cells that overexpressed folate receptor. Reactive oxygen species (ROS) generation in cancer cells under a 1-cm tissue was higher upon excitation of UCNPs with the 980 nm light than that with 660 nm irradiation. In vivo PDT treatments for deep-seated tumors demonstrated that NIR light-triggered PDT based on the nanoconstructs possessed remarkable therapeutic efficacy with tumor inhibition ratio up to 50% compared with conventional visible light-activated PDT with a noticeable reduced tumor inhibition ratio of 18%. These results indicate that the multifunctional nanoconstruct is a promising PDT agent for deep-seated tumor treatment and demonstrate a new paradigm for enhancing PDT efficacy.

PD-L1 expression is a feature of Epstein-Barr virus (EBV) associated malignancies such as nasopharyngeal carcinoma (NPC). Here, we found that EBV-induced latent membrane protein 1 (LMP1) and IFN-γ pathways cooperate to regulate programmed cell death protein 1 ligand (PD-L1). Expression of PD-L1 was higher in EBV positive NPC cell lines compared with EBV negative cell lines. PD-L1 expression could be increased by exogenous and endogenous induction of LMP1 induced PD-L1. In agreement, expression of PD-L1 was suppressed by knocking down LMP1 in EBV positive cell lines. We further demonstrated that LMP1 up-regulated PD-L1 through STAT3, AP-1, and NF-κB pathways. Besides, IFN-γ was independent of but synergetic with LMP1 in up-regulating PD-L1 in NPC. Furthermore, we showed that PD-L1 was associated with worse disease-free survival in NPC patients. These results imply that blocking both the LMP1 oncogenic pathway and PD-1/PD-L1 checkpoints may be a promising therapeutic approach for EBV positive NPC patients.

BackgroundHepatitis B virus (HBV) reactivation is a serious complication in patients with cancers and HBV infection undergoing immunosuppressant treatment or chemotherapy. However, the safety of anti-programmed cell death (PD) -1 and anti-programmed cell death-ligand 1 (PD-L1) therapy in these patients is unknown because they were excluded from clinical trials of immunotherapy.MethodsThis retrospective cohort study involved consecutive hepatitis B surface antigen (HBsAg) -positive cancer patients who were referred to Sun Yat-sen University Cancer Center and received an anti-PD-1/PD-L1 antibody between January 1, 2015 and July 31, 2018. The primary end point was the rate of the occurrence of HBV reactivation.ResultsIn total, 114 eligible patients were included, among whom 90 (79%) were male, and the median (range) age was 46 (16–76) years. Six patients (5.3%) developed HBV reactivation, occurring at a median of 18 weeks (range, 3–35 weeks) from the commencement of immunotherapy. Among these patients, all of them had undetectable baseline HBV DNA; one had prophylactic antiviral therapy while five did not; four were positive for Hepatitis B e antigen while the other two were negative. At reactivation, the median HBV DNA level was 3.89 × 104 IU/mL (range, 1.80 × 103–6.00 × 107 IU/mL); five had HBV-related hepatitis and one exhibited increasing HBV DNA level without alanine transaminase elevation. No HBV-related fatal events occurred. The lack of antiviral prophylaxis was the only significant risk factor for HBV reactivation (odds ratio, 17.50 [95% CI, 1.95–157.07], P = .004).ConclusionsHBV reactivation occurs in a subset of HBsAg-positive cancer patients undergoing anti-PD-1 or anti-PD-L1 immunotherapy. Regular monitoring of HBV DNA and antiviral prophylaxis are advised to prevent this potentially fatal complication.

The molecular basis for aging of the kidney is not well understood. MicroRNAs (miRNAs) contribute to processes such as development, differentiation, and apoptosis, but their contribution to the aging process is unknown. Here, we analyzed the miRNA expression profile of young (3-month) and old (24-month) rat kidneys and identified the biologic pathways and genes regulated by differentially expressed miRNAs. We observed upregulation of 18 miRNAs with aging, mainly regulating the genes associated with energy metabolism, cell proliferation, antioxidative defense, and extracellular matrix degradation; in contrast, we observed downregulation of 7 miRNAs with aging, principally targeting the genes associated with the immune inflammatory response and cell-cycle arrest. Bioinformatics analysis suggested that superoxide dismutase 2 (SOD2) and thioredoxin reductase 2 (Txnrd2), located in the mitochondria, are potential targets of miR-335 and miR-34a, respectively. Aging mesangial cells exhibited significant upregulation of miR-335 and miR-34a and marked downregulation of SOD2 and Txnrd2. miR-335 and miR-34a inhibited expression of SOD2 and Txnrd2 by binding to the 3Ј-untranslated regions of each gene, respectively. Overexpression of miR-335 and miR-34a induced premature senescence of young mesangial cells via suppression of SOD2 and Txnrd2 with a concomitant increase in reactive oxygen species (ROS). Conversely, antisense miR-335 and miR-34a inhibited senescence of old mesangial cells via upregulation of SOD2 and Txnrd2 with a concomitant decrease in ROS. In conclusion, these results suggest that miRNAs may contribute to renal aging by inhibiting intracellular pathways such as those involving the mitochondrial antioxidative enzymes SOD2 and Txnrd2. 22: 125222: -126122: , 201122: . doi: 10.1681 Kidney aging is an important clinical problem, not only because normal aging reduces renal function but also because of the high frequency of ESRD, renal cancer, and renal failure in elderly people. Renal aging is of interest as a general model for organ aging because renal function can be quantitatively assessed more readily than that of other organs in clinical practice. 1 At the present time, the molecular basis of renal aging is not clearly known. For example, nothing is known of the role of microRNAs (miRNAs) in the aging process of organs. J Am Soc NephrolmiRNAs are a novel class of small, regulatory, noncoding RNA molecules that inhibit the expression of multiple genes at the post-transcriptional level. miRNAs have been found to play a crucial role in development, differentiation, apoptosis, and metabolism and are involved in the pathogenesis of many human diseases. 2,3 Bioinformatics studies suggest that miRNAs may regulate Ͼ60% of all human genes. 4,5 Studies have shown that overexpression of miRNA lin-4 increases longevity in Caenorhabditis elegans, whereas loss of lin-4 leads to a