Population structure is a critical factor in shaping evolutionary dynamics. It constrains not only who interacts with whom, but also who learns from whom. In many real-world cases, such spatial constraints can lead to asymmetric interaction and strategy dispersal. For example, individuals who are geographically and socially too distant to interact physically may still learn from each other through social media. Despite the ubiquity of the asymmetry, their impact on evolutionary outcomes, particularly in the presence of structural heterogeneity, is not well understood. In this paper, we investigate their influence on evolutionary dynamics. Our analytical and simulation results demonstrate that although population structure can lead to the formation of clusters of cooperators, disrupting the balance between the interaction and dispersal graphs can severely impede cooperation. Moreover, we find that increased network heterogeneity exacerbates the cooperation-inhibiting effects. We also examine the roles of the interaction and dispersal networks separately. By modifying the connections in each network, we find that altering the dispersal network has a more pronounced effect on cooperation compared to the interaction network. Our work emphasizes the importance of the correlation between interaction and strategy dispersal and highlights that modifying the paths of strategy or information dissemination can be a more effective way of promoting social prosperity than modifying the interaction networks.
Obesity is closely related to the initiation and development of hepatocellular carcinoma (HCC). The regulatory mechanism of obesity-associated HCC remains unclear. HepG2 cells treated with palmitic acid (PA) and diethylnitrosamine (DEN)-induced HCC mice fed a high-fat diet (HFD) were established. The expression of miR-27a and B-cell translocation gene 2 (BTG2) mRNA and protein were detected via qPCR and western blotting. Prediction software and luciferase assays were employed to verify the miR-27a/BTG2 axis. The biological effects of HepG2 cells were evaluated with ORO staining, MTT assays, Transwell assays, Mito-Timer, and Mito-SOX staining. Significantly upregulated miR-27a and downregulated BTG2 mRNA and protein were observed in HepG2 cells and liver tissues of HCC mice. Overexpressing miR27a (mi-miR27a) markedly promoted cellular lipid accumulation, proliferation, and invasion, accompanied by aggravated mitochondrial dysfunction (increased fading and ROS products of mitochondria) in HepG2 cells. Additionally, these effects were further reinforced in HepG2 cells treated with mi-miR27a and PA. BTG2 was identified as a direct target and was negatively regulated by miR-27a. Similarly, BTG2 knockdown (sh-BTG2) had effects identical to those of mi-miR27a on HepG2 cells. Additionally, PA evidently enhanced these effects of sh-BTG2 in HepG2 cells. Moreover, BTG2 overexpression effectively reversed the effects of miR-27a, including lipotropic and oncogenic effects, and simultaneously promoted mitochondrial imbalance in HepG2 cells. Thus, obesity-associated miR-27a acts as an oncogene to promote lipid accumulation, proliferation, and invasion by negatively regulating BTG2-mediated mitochondrial dysfunction in HCC.
Hepatic carcinoma is one of the most common cancers worldwide, while its treatment remains a great challenge. Traditional therapeutic methods often have disadvantages such as limited therapeutic efficacy and potential side effects. In this study, we report the construction of bovine serum albumin (BSA)–stabilized manganese oxide (MnO2)/semiconducting polymer (SP) nanocomposites to combine photothermal therapy (PTT) and chemodynamic therapy (CDT) for treatment of hepatic carcinoma in living mouse models. Such nanocomposites are composed of BSA, SP, and MnO2 as the stabilizer, PTT, and CDT agent, respectively. SP produced local heat under near-infrared (NIR) laser irradiation for PTT, and MnO2 nanoparticles mediated CDT in the tumor microenvironment, leading to apoptosis of cancer cells. Such nanocomposite-mediated combinational therapy showed a much higher efficacy in inhibiting growth of subcutaneous HepG2 tumors in nude mice than sole treatment. This study thus provides a multifunctional nanoplatform for safe and effective treatment of hepatic carcinoma.
High transmembrane delivery efficiency of nanoparticles has attracted substantial interest for biomedical applications. It has been proved that the desired physicochemical properties of nanoparticles were efficient for obtaining a high cellular uptake capacity. On the other hand, biophysical stimuli from in situ microenvironment were also indicated as another essential factor in the regulation of cellular uptake capacity. Unfortunately, the influence of colony morphology on cellular uptake capacity was rarely analyzed. In this study, micropatterned PDMS stencils containing circular holes of 800/1,200 μm in diameter were applied to control colonies’ size. The amino-modified nanoparticles were cocultured with micropatterned colonies to analyze the influence of colonies’ morphology on the cellular uptake capacity of nanoparticles. Consequently, more endocytosed nanoparticles in larger colonies were related with a bigger dose of nanoparticles within a larger area. Additionally, the high cell density decreased the membrane–nanoparticles’ contacting probability but enhanced clathrin-mediated endocytosis. With these contrary effects, the cells with medium cell density or located in the peripheral region of the micropatterned colonies showed a higher cellular uptake capacity of nanoparticles.
Although legumain has been found to be a prognostic factor in both breast cancer and colorectal cancer, its effects on gastric cancer are unknown. In this study, we investigated effects of legumain on gastric cancer and the correlation between legumain expression and prognosis of gastric cancer patients. SGC7901 cells were transduced with legumain cDNA (SGC7901-hLeg) for overexpression of legumain or with legumain shRNA to knock down legumain. In vitro tumor migration was examined by wound healing assay. Furthermore, a tumorigenicity and metastasis mouse model was used to examine legumain function in vivo; asparaginyl endopeptidase inhibitor (AEPI, an inhibitor of legumain) was injected to the mice (i.p.) to evaluate its therapeutic effect. Tissue microarray analysis from 112 gastric cancer patients was performed to evaluate the association between legumain expression and the cumulative survival time. Legumain was highly expressed in gastric cancer patients and some gastric cancer cell lines. Legumain promoted gastric cell migration in vitro and promoted gastric tumor growth and metastasis in vivo, and these effects were reversed by knockdown of legumain with shRNA or treated with AEPI. In gastric cancer clinical samples, legumain expression in tumor was significantly higher than in nontumor and was negatively associated with the cumulative survival rate. In conclusion, legumain was highly expressed in gastric adenocarcinoma; legumain promoted gastric cancer tumorigenesis and metastasis in vitro and in vivo. Legumain expression in tumor was a poor prognostic factor for gastric cancer patients, and legumain could be a potential target molecule for gastric cancer therapy in clinic.