Circular RNAs (circRNAs) represent a distinct group of RNA molecules produced through back-splicing of precursor mRNAs. Their covalently closed structure, which lacks both a 5′ cap and a poly(A) tail, renders them highly resistant to exonucleolytic degradation and contributes to their remarkable intracellular stability. Although circRNAs were historically viewed as noncoding transcripts, accumulating evidence indicates that certain circRNAs can undergo translation under appropriate molecular contexts. Two major modes of noncanonical translation have been described so far: initiation mediated by internal ribosome entry sites (IRESs) and translation triggered by N6-methyladenosine (m6A) modification. Recent studies have revealed that, beyond their canonical classification as non-coding RNAs, circRNAs can give rise to functional peptides through cap-independent translational mechanisms. Accumulating evidence indicates that circRNA-encoded peptides participate in key biological processes during tumor initiation and progression by modulating tumor-associated signaling pathways and protein-protein interaction networks. Functionally, these peptides may promote tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition, while others exert tumor-suppressive effects by inhibiting oncogenic signaling pathways or interfering with critical protein interactions. Their dual and context-dependent functions highlight the complexity of circRNA-mediated regulation and suggest that these translation products participate in multiple layers of tumor initiation and progression. In this review, we synthesize current knowledge regarding the molecular mechanisms that enable circRNAs to be translated, with particular attention to IRES-driven initiation, m6A-dependent regulation, ribosome accessibility, and the structural determinants required for translation competence. We further summarize well-characterized circRNA-encoded peptides and discuss how they influence tumor-associated signaling networks. In addition, we examine the potential translational applications of these peptides, including their value as diagnostic indicators, prognostic markers, or therapeutic entry points. Their inherent sequence stability, relative expression specificity, and detectability in clinical specimens make circRNA-derived peptides promising candidates for future biomarker and therapeutic development. Overall, circRNA translation research is reshaping our understanding of RNA function and offers new perspectives for studying tumor biology. We propose that expanding investigations into circRNA-encoded peptides will not only improve the mechanistic resolution of cancer research but may also pave the way for innovative strategies in precision oncology, including RNA-based therapeutics and peptide-targeting interventions.

Circular RNAs (circRNAs) represent a distinct group of RNA molecules produced through back-splicing of precursor mRNAs. Their covalently closed structure, which lacks both a 5′ cap and a poly(A) tail, renders them highly resistant to exonucleolytic degradation and contributes to their remarkable intracellular stability. Although circRNAs were historically viewed as noncoding transcripts, accumulating evidence indicates that certain circRNAs can undergo translation under appropriate molecular contexts. Two major modes of noncanonical translation have been described so far: initiation mediated by internal ribosome entry sites (IRESs) and translation triggered by N6-methyladenosine (m6A) modification. Recent studies have revealed that, beyond their canonical classification as non-coding RNAs, circRNAs can give rise to functional peptides through cap-independent translational mechanisms. Accumulating evidence indicates that circRNA-encoded peptides participate in key biological processes during tumor initiation and progression by modulating tumor-associated signaling pathways and protein-protein interaction networks. Functionally, these peptides may promote tumor cell proliferation, migration, invasion, and epithelial-mesenchymal transition, while others exert tumor-suppressive effects by inhibiting oncogenic signaling pathways or interfering with critical protein interactions. Their dual and context-dependent functions highlight the complexity of circRNA-mediated regulation and suggest that these translation products participate in multiple layers of tumor initiation and progression. In this review, we synthesize current knowledge regarding the molecular mechanisms that enable circRNAs to be translated, with particular attention to IRES-driven initiation, m6A-dependent regulation, ribosome accessibility, and the structural determinants required for translation competence. We further summarize well-characterized circRNA-encoded peptides and discuss how they influence tumor-associated signaling networks. In addition, we examine the potential translational applications of these peptides, including their value as diagnostic indicators, prognostic markers, or therapeutic entry points. Their inherent sequence stability, relative expression specificity, and detectability in clinical specimens make circRNA-derived peptides promising candidates for future biomarker and therapeutic development. Overall, circRNA translation research is reshaping our understanding of RNA function and offers new perspectives for studying tumor biology. We propose that expanding investigations into circRNA-encoded peptides will not only improve the mechanistic resolution of cancer research but may also pave the way for innovative strategies in precision oncology, including RNA-based therapeutics and peptide-targeting interventions.

The functional realization of proteins and other biological macromolecules depends on conformational dynamics and allosteric regulation, and elucidating their molecular mechanisms is an important foundation for understanding life processes. Molecular dynamics simulations are a powerful tool for investigating conformational evolution at the atomic level. However, traditional methods are limited by simulation timescales and high free-energy barriers, making it difficult to effectively capture rare conformations and their transition pathways. As a result, the development of enhanced sampling techniques has become key to overcoming this bottleneck. As a classical enhanced sampling technique, metadynamics suffers from several shortcomings, including strong dependence on collective variables and significant errors caused by bias potential accumulation. This article reviews three major improvement strategies. The first combines stochastic resetting with metadynamics, using trajectory-resetting mechanisms to improve sampling efficiency while avoiding the difficulty of optimizing collective variables. The second, SinkMeta, employs a “sinking” bias effect to enable efficient exploration of specific regions and paths. The third, OPES-based hybrid methods, improve the stability of free-energy estimation by optimizing the target distribution or the way the bias is constructed. These methods provide new ideas for characterizing free-energy landscapes and studying conformational transitions in complex biological systems, while also promoting the continued development of enhanced sampling methodologies.

Icaritin(ICT)is an 8-isopentenylflavonoid,which is the main effective component of the tra-ditional Chinese medicine Epimedium.Previously,we found that Icaritin inhibits the growth of glioblasto-ma(GBM)cells.Herein we aim to study the in vivo anti-GBM effectiveness of Icaritin and explore its mechanism.The results of MTT assay,flow cytometry,comet assay and cellular immunofluorescence as-say in vitro showed that ICT inhibited the proliferation of four kinds of GBM cells,U87,U251,U118 and A172,induced early apoptosis(P＜0.001)and late apoptosis(P＜0.05)in U87 cells,induced DNA damage in U87 cells,and blocked the growth of U87 cells at the G0/G1 phase(P＜0.0001)in a concen-tration-time-dependent manner.In vivo subcutaneous tumor transplantation tumor experiments showed that feeding 200 mg/kg(P＜0.01)and 400 mg/kg(P＜0.001)ICT had a significant inhibitory effect on the growth of GBM subcutaneous tumors,and had no significant toxic effects on heart,liver,spleen,lung and kidney tissues.The results of network pharmacological analysis,molecular docking and cellular thermodynamic experiments showed that there were 26 possible target proteins between ICT and GBM,a-mong which the expression of p53 in GBM tissues was significantly(P＜0.001)higher than in normal tis-sues,and the binding energy of ICT and p53 was lower;cellular thermodynamic experiments verified that ICT significantly enriched the level of p53 in the living cells of GBM,which indicated that ICT could tar-get p53.The expression of key proteins in the DNA damage repair and apoptosis-associated FOXO signa-ling pathway was detected by ICT.The results showed that the expression of ATR(P＜0.01),P53(P＜0.001),P21(P＜0.05)and γ-H2AX(P＜0.05)was up-regulated,whereas the expression of Cyc-lin E1(P＜0.01),E2F1(P＜0.05),CDK2(P＜0.01),Rb(P＜0.001),p-Rb(P＜0.0001)and WRN(P＜0.0001)expression were down-regulated.There was no significant change in the expres-sion of FOXO 1 in the FOXO pathway or a significant down-regulation of its phosphorylation level.This study demonstrated that ICT could effectively inhibit the growth of GBM cells in vivo.It targets p53 to regulate the DNA damage repair pathway and FOXO signaling pathway to induce GBM cell cycle arrest and apoptosis.

Icaritin(ICT)is an 8-isopentenylflavonoid,which is the main effective component of the tra-ditional Chinese medicine Epimedium.Previously,we found that Icaritin inhibits the growth of glioblasto-ma(GBM)cells.Herein we aim to study the in vivo anti-GBM effectiveness of Icaritin and explore its mechanism.The results of MTT assay,flow cytometry,comet assay and cellular immunofluorescence as-say in vitro showed that ICT inhibited the proliferation of four kinds of GBM cells,U87,U251,U118 and A172,induced early apoptosis(P＜0.001)and late apoptosis(P＜0.05)in U87 cells,induced DNA damage in U87 cells,and blocked the growth of U87 cells at the G0/G1 phase(P＜0.0001)in a concen-tration-time-dependent manner.In vivo subcutaneous tumor transplantation tumor experiments showed that feeding 200 mg/kg(P＜0.01)and 400 mg/kg(P＜0.001)ICT had a significant inhibitory effect on the growth of GBM subcutaneous tumors,and had no significant toxic effects on heart,liver,spleen,lung and kidney tissues.The results of network pharmacological analysis,molecular docking and cellular thermodynamic experiments showed that there were 26 possible target proteins between ICT and GBM,a-mong which the expression of p53 in GBM tissues was significantly(P＜0.001)higher than in normal tis-sues,and the binding energy of ICT and p53 was lower;cellular thermodynamic experiments verified that ICT significantly enriched the level of p53 in the living cells of GBM,which indicated that ICT could tar-get p53.The expression of key proteins in the DNA damage repair and apoptosis-associated FOXO signa-ling pathway was detected by ICT.The results showed that the expression of ATR(P＜0.01),P53(P＜0.001),P21(P＜0.05)and γ-H2AX(P＜0.05)was up-regulated,whereas the expression of Cyc-lin E1(P＜0.01),E2F1(P＜0.05),CDK2(P＜0.01),Rb(P＜0.001),p-Rb(P＜0.0001)and WRN(P＜0.0001)expression were down-regulated.There was no significant change in the expres-sion of FOXO 1 in the FOXO pathway or a significant down-regulation of its phosphorylation level.This study demonstrated that ICT could effectively inhibit the growth of GBM cells in vivo.It targets p53 to regulate the DNA damage repair pathway and FOXO signaling pathway to induce GBM cell cycle arrest and apoptosis.

Objective To evaluate the efficacy of two kinds of biliary stent placement in the treatment of high bile duct carcinoma.Methods the clinical data of 136 patients with hilar cholangiocarcinoma who underwent biliary stent implantation in Nanyang Central Hospital from January 2021 to September 2023 were analyzed retrospectively.According to the mode of biliary stent placement,the patients were divided into ERCP group(n=86)and transoral cholangiopancreatoscopy group(n=50).In this study,SPSS26.0 was used for analysis.The age,related test indexes,days of hospitalization,postoperative complications,incidence of liver failure,remission rate of jaundice,stent material and patency rate were observed in the two groups.Results all patients completed the operation successfully.The two groups compared the incidence of postoperative liver failure,postoperative remission rate of jaundice,different material stents,postoperative complications and short-term patency rate,there was no significant statistical significance(P＞0.05).There were significant differences in postoperative complications between the two groups(t=12.02,P＜0.05).Compared with postoperative biliary tract infection and postoperative bleeding,the postoperative biliary tract infection and postoperative bleeding in ERCP group were 26.7％and 11.6％respectively,which were significantly higher than those in transoral cholangiopancreatoscopy group 10.0％and 2.0％(x2=5.42,3.94;P＜0.05).Conclusion of the mean hospitalization days between the two patient groups,Transoral cholangioscopy(10.78±2.17)d＜ERCP(12.91±2.96)d.Compared with the 7th day after operation,the liver function of the two groups was significantly improved and the related test indexes decreased significantly.There was no significant difference in postoperative complications and short-term patency rate between plastic stent and metal stent(P＞0.05).When the patency time was more than 6 months,the patency rate of metal stent was significantly higher than that of plastic stent(P＜0.05).Conclusion The placement of bile duct stent by ERCP and Oral choledochoscopy is effective in relieving clinical symptoms of high cholangiocarcinoma and can improve the quality of life of patients.Transoral cholangiopancreatoscopy has low complication rate,faster recovery,greater advantage,but higher cost;plastic stents are beneficial for patients with short expected survival time,and metal stents are more suitable for patients with long expected survival time.

The density and composition of lymphocytes infiltrating colon tumors serve as predictive factors for the clinical outcome of colon cancer.Our previous studies highlighted the potent anti-cancer properties of the principal compounds found in Garcinia yunnanensis(YTE-17),attributing these effects to the regu-lation of multiple signaling pathways.However,knowledge regarding the mechanism and effect of YTE-17 in the prevention of colorectal cancer is limited.In this study,we conducted isobaric tags for relative and absolute quantification(iTRAQ)analysis on intestinal epithelial cells(IECs)exposed YTE-17,both in vitro and in vivo,revealing a significant inhibition of the Wnt family member 5a(Wnt5a)/c-Jun N-terminal kinase(JNK)signaling pathway.Subsequently,we elucidated the influence and mechanism of YTE-17 on the tumor microenvironment(TME),specifically focusing on macrophage-mediated T helper 17(Th17)cell induction in a colitis-associated cancer(CAC)model with Wnt5a deletion.Additionally,we performed the single-cell RNA sequencing(scRNA-seq)on the colonic tissue from the Wnt5a-deleted CAC model to characterize the composition,lineage,and functional status of immune mesenchymal cells during different stages of colorectal cancer(CRC)progression.Remarkably,our findings demon-strate a significant reduction in M2 macrophage polarization and Th17 cell phenotype upon treatment with YTE-17,leading to the restoration of regulatory T(Treg)/Th17 cell balance in azoxymethane(AOM)/dextran sodium sulfate(DSS)model.Furthermore,we also confirmed that YTE-17 effectively inhibited the glycolysis of Th17 cells in both direct and indirect co-culture systems with M2 macrophages.Notably,our study shed light on potential mechanisms linking the non-canonical Wnt5a/JNK signaling pathway and well-established canonical β-catenin oncogenic pathway in vivo.Specifically,we proposed that Wnt5a/JNK signaling activity in IECs promotes the development of cancer stem cells with β-catenin activity within the TME,involving macrophages and T cells.In summary,our study undergoes the po-tential of YTE-17 as a preventive strategy against CRC development by addressing the imbalance with the immune microenvironment,thereby mitigating the risk of malignancies.

Near-infrared spectroscopy(NIRS) combined with band screening method and modeling algorithm can be used to achieve the rapid and non-destructive detection of the traditional Chinese medicine(TCM) production process. This paper focused on the ginkgo leaf macroporous resin purification process, which is the key technology of Yinshen Tongluo Capsules, in order to achieve the rapid determination of quercetin, kaempferol and isorhamnetin in effluent. The abnormal spectrum was eliminated by Mahalanobis distance algorithm, and the data set was divided by the sample set partitioning method based on joint X-Y distances(SPXY). The key information bands were selected by synergy interval partial least squares(siPLS); based on that, competitive adaptive reweighted sampling(CARS), successive projections algorithm(SPA) and Monte Carlo uninformative variable(MC-UVE) were used to select wavelengths to obtain less but more critical variable data. With selected key variables as input, the quantitative analysis model was established by genetic algorithm joint extreme learning machine(GA-ELM) algorithm. The performance of the model was compared with that of partial least squares regression(PLSR). The results showed that the combination with siPLS-CARS-GA-ELM could achieve the optimal model performance with the minimum number of variables. The calibration set correlation coefficient R_c and the validation set correlation coefficient R_p of quercetin, kaempferol and isorhamnetin were all above 0.98. The root mean square error of calibration(RMSEC), the root mean square error of prediction(RMSEP) and the relative standard errors of prediction(RSEP) were 0.030 0, 0.029 2 and 8.88%, 0.041 4, 0.034 8 and 8.46%, 0.029 3, 0.027 1 and 10.10%, respectively. Compared with the PLSR me-thod, the performance of the GA-ELM model was greatly improved, which proved that NIRS combined with GA-ELM method has a great potential for rapid determination of effective components of TCM.
Algorithms ; Ginkgo biloba ; Least-Squares Analysis ; Plant Leaves ; Spectroscopy, Near-Infrared

The aim of this paper was to investigate the preventive and therapeutic effects of Xiaoer Feike Granules(XEFK) on chronic bronchitis in rats and its mechanism. Except for 10 rats in the blank group, the remaining 50 of the 60 SD rats were used to establish a model of chronic bronchitis induced by LPS. On the 22 nd day, the model rats were randomly divided into 5 groups according to their body weight, and administrated with purified water, Keteling Capsules 0.11 g·kg~(-1), XEFK 3.2, 1.6 and 0.8 g·kg~(-1)(the dosing concentrations were 0.32, 0.16, 0.08 g·mL~(-1), respectively). These rats took the corresponding drug orally once a day, for consecutive 21 days. The rats were anesthetized 1 hour after the last administration, and the lavage bronchus and alveoli were collected. Then, after the fixation of the smear, neutrophils were counted microscopically, and the contents of glutathione peroxidase(GSH-Px), superoxide dismutase(SOD) and malondialdehyde(MDA) in the bronchoalveolar lavage fluid(BALF) were detected by colorimetric method. Flow cytometry was used to detect the content changes of T cell subsets CD4~+, CD8~+, CD4~+/CD8~(+ )in serum. Hemorheology related indexes were detected by automatic hemorheology. Enzyme-linked immunosorbent assay(ELISA) was used to detect the contents of tumor necrosis factor-α(TNF-α), interleukin-1β(IL-1β), IL-2, IL-6 and IL-10 in serum. The expression of TNF-α and IL-10 mRNA in lung was detected by Real-time quantitative PCR(RT-qPCR). HE staining was used to observe the pathological changes in the bronchitis tissues. Compared with the model group, XEFK high and medium dose groups could significantly reduce the contents of neutrophils and MDA in bronchial lavage fluid, and increase the activities of GSH-Px and SOD in BALF, and repair the chronic inflammatory cell infiltration and lymphoid tissue hyperplasia in the bronchial mucosal layer and submucosal layer. The high-dose group could reduce the plasma viscosity of rats, but there was no statistical difference in other hemorheological indexes. CD4~+, CD8~+, CD4~+/CD8~+, IL-2 and IL-10 contents in each dose group were significantly increased, and TNF-α, IL-1β and IL-6 contents were significantly decreased in serum. Each dose group could significantly down-regulate the expression level of TNF-α mRNA in the lung and increase the expression of IL-10 mRNA. XEFK could reduce lipid peroxidation, increase the content of peripheral blood T cell subsets, regulate the release and secretion of inflammatory factors, and repair the morphological and pathological changes of bronchial tissue. Its mechanism might be related to the improvement of inflammatory response and the enhancement of immune function.
Animals ; Bronchitis, Chronic/drug therapy* ; Drugs, Chinese Herbal/pharmacology* ; Glutathione Peroxidase ; Lipopolysaccharides ; Lung ; Rats ; Rats, Sprague-Dawley ; Tumor Necrosis Factor-alpha

Objective:To investigate the topological alterations in brain functional networks following comprehensive treatment including brain-computer interface (BCI) training in subacute stroke subjects. Methods:From January, 2018 to June, 2019, 14 subacute stroke patients with moderate to severe upper limbs paralysis accepted routine physical therapy, occupational therapy and BCI training based on motor imagery, for four weeks. They were assessed with Fugl-Meyer Assessment-Upper Extremities (FMA-UE), Action Research Arm Test (ARAT) and Wolf Motor Function Test (WMFT) before and after treatment, while the functional connectivity (FC) was investigated with resting state functional magnetic resonance imaging. Results:The scores of FMA-UE, ARAT and WMFT increased after treatment (|t| > 5.298, Z = -3.297, P < 0.01). The FC also increased across the whole brain, including temporal, parietal, occipital lobes and subcortical regions. The FC between left piriform cortex of parietal lobule (BA5L) and right medial surface of temporal lobe (BA48R), as well as those between left precentral gyrus (BA4L) and right anterior transverse temporal gyrus (BA41R) (r > 0.416, P < 0.05). Conclusion:Comprehensive rehabilitation including BCI training may promote recovery of motor function and activities of FC in brain in subacute stroke patients.