Treg Immunomodulation Contributes to the Anti-atherosclerotic Effects of Huxin Formula in ApoE-/- Mice.

OBJECTIVE: To explore the effects of Huxin formula (HXF) in curtailing atherosclerosis and its underlying mechanism. METHODS: According to random number table method, 24 specific pathogen free male ApoE-/- mice were randomly divided into model group, HXF low-dose (HXF-L) group (8.4 g/kg daily), HXF high-dose (HXF-H) group (16.8 g/kg daily), and pravastatin (8 mg/kg daily) group in Experiment I (n=6 per group). C57BL/6J mice served as the control group (n=6). ApoE-/- mice in HXF-L, HXF-H, pravastatin groups were fed a Western diet and administered continuously by gavage for 12 weeks, while C57BL/6J mice in the control group were fed conventional lab mouse chow for 12 weeks. Further, Tregs were depleted by weekly intraperitoneal injection of purified anti-mouse CD25 antibody (PC61, 250 µg per mouse) for 4 weeks in Experiment II (n=6 per group). Oil Red O and Masson staining were used to evaluate the plaque area and aortic root fibrosis. The CD4+CD25+Foxp3+Treg counts in the lymph nodes and spleen cells were detected using flow cytometric analysis. The transforming growth factor-ß1 (TGF-ß1), interleukin (IL)-10, and IL-6 serum levels were examined by MILLIPLEX® MAP technology. Quantitative real-time reverse transcription PCR (qRT-PCR) and Western blot were utilized to assess the expression of TGF-ß mRNA and protein in the aorta. The expression of CD4+T lymphocytes, macrophages and smooth muscle cells in the aortic root were detected by immunofluorescence staining. RESULTS: HXF reduced plaque area in ApoE-/- mice (P<0.01). HXF increased the Treg counts in the lymph nodes and spleen cells (P<0.05 or P<0.01). Moreover, HXF alleviated inflammatory response via elevating IL-10 and TGF-ß 1 serum levels (P<0.05), while decreasing the IL-6 serum levels in ApoE-/- mice (P>0.05). Also, HXF upregulated the expression of TGF-ß mRNA and protein in the aorta (P<0.05). Additionally, HXF attenuated CD4+T lymphocytes, macrophages and smooth muscle cells in aortic root plaque (P<0.01). Furthermore, the depletion of Tregs with CD25 antibody (PC61) curtailed the reduction in plaque area and aortic root fibrosis by HXF (P<0.01). CONCLUSION: HXF relieved atherosclerosis, probably by restraining inflammatory response, reducing inflammatory cell infiltration and attenuating aortic root fibrosis by increasing Treg counts.

Radiomic signatures associated with tumor immune heterogeneity predict survival in locally recurrent nasopharyngeal carcinoma.

BACKGROUND: The prognostic value of traditional clinical indicators for locally recurrent nasopharyngeal carcinoma (lrNPC) is limited due to their inability to reflect intratumor heterogeneity. We aimed to develop a radiomic signature to reveal tumor immune heterogeneity and predict survival in lrNPC. METHODS: This multicenter, retrospective study included 921 patients with lrNPC. A machine learning signature and nomogram based on pretreatment MRI features were developed for predicting overall survival (OS) in a training cohort and validated in two independent cohorts. A clinical nomogram and an integrated nomogram were constructed for comparison. Nomogram performance was evaluated by concordance index (C-index) and receiver operating characteristic curve analysis. Accordingly, patients were classified into risk groups. The biological characteristics and immune infiltration of the signature were explored by RNA sequencing (RNA-seq) analysis. RESULTS: The machine learning signature and nomogram demonstrated comparable prognostic ability to a clinical nomogram, achieving C-indexes of 0.729, 0.718, and 0.731 in the training, internal, and external validation cohorts, respectively. Integration of the signature and clinical variables significantly improved the predictive performance. The proposed signature effectively distinguished patients between risk groups with significantly distinct OS rates. Subgroup analysis indicated the recommendation of local salvage treatments for low-risk patients. Exploratory RNA-seq analysis revealed differences in interferon response and lymphocyte infiltration between risk groups. CONCLUSIONS: An MRI-based radiomic signature predicted OS more accurately. The proposed signature associated with tumor immune heterogeneity may serve as a valuable tool to facilitate prognostic stratification and guide individualized management for lrNPC patients.

Radiomic signatures reveal multiscale intratumor heterogeneity associated with tissue tolerance and survival in re-irradiated nasopharyngeal carcinoma: a multicenter study.

BACKGROUND: Post-radiation nasopharyngeal necrosis (PRNN) is a severe adverse event following re-radiotherapy for patients with locally recurrent nasopharyngeal carcinoma (LRNPC) and associated with decreased survival. Biological heterogeneity in recurrent tumors contributes to the different risks of PRNN. Radiomics can be used to mine high-throughput non-invasive image features to predict clinical outcomes and capture underlying biological functions. We aimed to develop a radiogenomic signature for the pre-treatment prediction of PRNN to guide re-radiotherapy in patients with LRNPC. METHODS: This multicenter study included 761 re-irradiated patients with LRNPC at four centers in NPC endemic area and divided them into training, internal validation, and external validation cohorts. We built a machine learning (random forest) radiomic signature based on the pre-treatment multiparametric magnetic resonance images for predicting PRNN following re-radiotherapy. We comprehensively assessed the performance of the radiomic signature. Transcriptomic sequencing and gene set enrichment analyses were conducted to identify the associated biological processes. RESULTS: The radiomic signature showed discrimination of 1-year PRNN in the training, internal validation, and external validation cohorts (area under the curve (AUC) 0.713-0.756). Stratified by a cutoff score of 0.735, patients with high-risk signature had higher incidences of PRNN than patients with low-risk signature (1-year PRNN rates 42.2-62.5% vs. 16.3-18.8%, P < 0.001). The signature significantly outperformed the clinical model (P < 0.05) and was generalizable across different centers, imaging parameters, and patient subgroups. The radiomic signature had prognostic value concerning its correlation with PRNN-related deaths (hazard ratio (HR) 3.07-6.75, P < 0.001) and all causes of deaths (HR 1.53-2.30, P < 0.01). Radiogenomics analyses revealed associations between the radiomic signature and signaling pathways involved in tissue fibrosis and vascularity. CONCLUSIONS: We present a radiomic signature for the individualized risk assessment of PRNN following re-radiotherapy, which may serve as a noninvasive radio-biomarker of radiation injury-associated processes and a useful clinical tool to personalize treatment recommendations for patients with LANPC.

Neuroprotective role of delta-opioid receptors against mitochondrial respiratory chain injury.

It is recognized in recent years that activation of delta-opioid receptor (DOR) elicits neuroprotection against hypoxia and ischemia. However, the underlying mechanisms are not well understood yet. Mitochondrial dysfunction plays a key role in hypoxic neuronal injury, but the effect of DOR activation on neurons with a mitochondrial respiratory chain deficiency is poorly elucidated. In this study we tested the effects of DOR activation and inhibition on cultured cortical neurons after inhibiting mitochondrial respiratory chain with sodium azide (NaN(3)) in days 8 cultures. Neuronal injury was assessed by lactate dehydrogenase release. Changes in DOR proteins were investigated using an antibody against the N-terminus of the DOR, which recognizes the 60, 48, and 32 kDa proteins. Our main findings are that 1) delta- but not mu-opioid receptor activation reduces NaN(3)-induced neuronal damage, and this neuroprotective effect is abolished by DOR antagonist (naltrindole, NTI); 2) prolonged DOR inhibition with NTI further increases NaN(3)-induced neuronal damage; 3) NaN(3) treatment down-regulates DOR protein levels in neurons, and the 60 and 32 kDa proteins are particularly sensitive; 4) DADLE, besides activating DOR directly, also reverses the decrease of neuronal DOR protein levels induced by NaN(3), which may contribute greatly to its neuroprotective effect; 5) NTI reverses NaN(3)-induced down-regulation of DOR proteins as well, the effect of NTI amplifying NaN(3)-induced neuronal damage therefore is probably due to its inhibition on DOR activity only. In conclusion, these data suggest that DOR activation plays an important role in neuroprotection against mitochondrial respiratory chain injury.