Tao-Sheng Li

Tumor microenvironment plays a pivotal role in regulating the biological properties of cancer cells. Interstitial fluid hydrostatic pressure (HP) generally increases in malignant solid tumors. While our recent work has demonstrated that elevated HP stabilizes HIF‐1α expression in cancer cells, here we further investigate whether elevated HP promotes cancer cells to acquire stemness features. Our results showed that exposure to 50 mmHg HP for 48 h did not significantly change the survival or morphology of human breast cancer cells. However, 50 mmHg HP stimulation significantly increased aldehyde dehydrogenase (ALDH) activity and upregulated HIF‐1α and stemness markers (CD44 and SSEA‐1) in MCF‐7 and BT‐474 but not in MDA‐MB‐453 breast cancer cell lines. Correspondingly, β‐catenin was significantly enhanced in MCF‐7 and BT‐474 breast cancer cell lines under 50 mmHg HP stimulation and was negatively expressed in MDA‐MB‐453 breast cancer cells. Hypoxia (1% O ₂ ) exposure for 48 h also significantly enhanced the expression of β‐catenin only in MCF‐7 cells and BT‐474 breast cancer cell lines, but increased HIF‐1α expression and ALDH activity in all breast cancer cell lines tested, including the β‐catenin‐deficient MDA‐MB‐453 cells. Therefore, we conclude that elevated HP in malignant tumors may facilitate the acquisition of ‘stemness’ characteristics of cancer cells by enhancing HIF‐1α expression via β‐catenin.

Background: Atherosclerotic carotid plaque is the main cause of cerebrovascular diseases, but the molecular and cellular mechanisms involving in carotid plaque formation have not yet been fully uncovered. Methods: Single cell RNA sequencing of human carotid plaques was used to identify major cell types. Cell‐cell communication and machine learning analyses were used to determine the key cell cluster involved in plaque development. In vitro experiments were conducted to explore the role of SPP1 (osteopontin) in foam cells formation. Clinical and histological analyses were also performed to validate the involvement of osteopontin in atherosclerosis. Results: Eight distinguishable major cell types were identified in atherosclerotic carotid tissue. Cell‐cell communication and machine learning analyses identified SPP1 ^hi macrophage as the key cell cluster in plaque development, and functional annotation further highlighted the involvement of hypoxia response and cholesterol metabolism. Culturing mouse macrophages under 1% O ₂ hypoxia condition with the addition of oxidized low‐density lipoprotein (ox‐LDL) significantly induced membrane translocation of CD36 and SR‐A, enhanced the expression of SPP1 (osteopontin), promoted foam cells formation, and activated NF‐κB pathway to release proinflammatory cytokines. All these changes of macrophages under hypoxia and ox‐LDL stimulations were effectively mitigated by inhibiting intracellular osteopontin. Clinical data and histological analysis of surgical resected carotid plaque tissue samples also confirmed the role of osteopontin in atherosclerosis. Conclusions: Intracellular osteopontin of macrophages promotes plaque formation by inducing foam cells and releasing proinflammatory cytokines. Our data provide novel mechanistical insight and therapeutic strategy on atherosclerotic carotid plaque.

Background/Objectives: Epidemiological and clinical studies have linked both hypothyroidism and hyperthyroidism to adverse cardiac outcomes, including heart failure and myocardial fibrosis. Triiodothyronine (T3), a biologically active thyroid hormone, is important for cardiovascular homeostasis. While the effects of physiological and non-physiological T3 levels on cardiomyocytes have been extensively investigated, the impact of hypothyroidism and hyperthyroidism on cardiac stromal cells (CSCs), which constitute the majority of the cells in the heart, remains understudied. Given CSCs’ essential role in extracellular matrix (ECM) remodeling and paracrine signaling, understanding their response to altered T3 states is necessary to fully elucidate the thyroid hormone-induced cardiac responses. Methods: Cardiac stromal cells were isolated from human atrial appendages and cultured under hypothyroid (0 nM T3), euthyroid (2.5 nM T3), and hyperthyroid (25 nM T3) conditions for 24 (short term) and 120 h (long term). The cells were harvested after 24 h of treatment using trypsin and automatically counted, and their ECM-related gene and growth factor expression levels were assessed using quantitative RT-PCR. Cardiac glucose uptake in hypothyroid, euthyroid, and hyperthyroid mice was monitored using [18F]-FDG PET/CT at acute (7 days) and chronic (42 days) time points. Results: Both hypo- and hyperthyroidism significantly increased the number of CSCs harvested after 24 h. There were acute alterations in the expression of the ECM-related genes COL1A1, COL3A1, TIMP3 (p < 0.05), and TIMP1 (p < 0.01). Similarly, growth factors such as PDGF-A (p < 0.001), TGF-b, and IGF1 (p < 0.05) were transiently upregulated under non-physiological T3 conditions, especially hypothyroidism. Most of these alterations were attenuated or reversed at the 120 h time point. In vivo PET imaging revealed significant increases in cardiac glucose uptake under acute hypothyroidism (p < 0.05) and decreases under acute hyperthyroidism (p < 0.05). However, these metabolic shifts normalized with chronic exposure, paralleling the transient nature of the gene expression changes observed in vitro. Conclusions: Non-physiological T3 concentrations induce proliferation and changes in ECM-related and growth factor gene expression in CSCs. Most of these changes are acute and return to normal levels after chronic exposure. These transient cellular responses correlate closely with the cardiac metabolic response patterns to acute and chronic hypothyroidism and hyperthyroidism.

Background: Stromal cells are known to play critical roles in the development and progression of solid tumors including lung cancers. This study was proposed to clarify the biological features of stromal cells from intratumoral, peritumoral lung, and distal lung tissues of primary lung adenocarcinoma patients. Methods: Surgically resected lung lobes containing primary adenocarcinoma were used for isolating stromal cells. Tumor tissue, peritumoral lung tissue, and distal lung tissue were sampled and cut into small pieces for culture as “explants.” The biological features of stromal cells were evaluated by cell isolating efficiency, cell morphology, cell surface marker, gene expression profile, and cytokine secretion. Results: Spindle shaped fibroblast‐like cells were outgrown successfully from the “explants” with comparable efficiency among different tissues. All outgrowth cells were vimentin‐positive and cytokeratin‐negative, consistent with stromal cell phenotypes. Quantitative analysis on the width‐to‐length ratio of cells indicated different morphological differences among stromal cells. Moreover, the expression of α‐smooth muscle actin (α‐SMA), a marker for cancer‐associated fibroblasts (CAFs), was more extensively observed in stromal cells from tumor tissues than others and, its PCR array showed higher expression of extracellular matrix (ECM)‐related factors COL11A1 and TIMP3 , in contrast, cytokine array analysis revealed more abundant release of immune‐suppressive factors from stromal cells of peritumoral tissues. Conclusion: Stromal cells from tumor, peritumoral, and distal lung tissues display distinct biological characteristics. Further investigation is needed to elucidate their specific roles in tumor progression.

Angiogenesis is crucial for tissue repair and the treatment of ischemic diseases, yet effective small‐molecule proangiogenic agents are lacking in clinical practice. Chalcone‐based compounds are of interest due to their diverse biological activities. This study aimed to synthesize and evaluate the proangiogenic potential of a series of novel chalcone derivatives and to elucidate their structure–activity relationship (SAR) using computational chemistry. We synthesized and tested six chalcone derivatives (1a–1f), with compound ( E )‐1‐(3,4‐dimethoxyphenyl)‐3‐(3‐hydroxy‐4‐methoxyphenyl)prop‐2‐en‐1‐one (1c) exhibiting the highest activity. In the zebrafish model, treatment with 1c significantly increased the formation of branch points and vessel outgrowth in the subintestinal vein (SIV) (number of branch points: 1c group 2.28 ± 0.19, control group 0.79 ± 0.17; p < 0.001). Using Tg( fli1:egfp ) transgenic zebrafish, we observed that 1c dramatically promoted the remodeling of the caudal vein plexus (CVP), leading to a significant increase in the number of intercapillary spaces (1c group 16.3 ± 1.9, mock group 11.6 ± 2). Mechanistically, real‐time polymerase chain reaction (RT‐PCR) results showed that 1c treatment upregulated the expression of key angiogenic genes cadherin 5 and neuropilin 1a, while downregulating the expression of fms‐related receptor tyrosine kinase 1. Furthermore, the chick embryo chorioallantoic membrane (CAM) assay confirmed that 1c effectively induced vascular network formation. Computational chemistry analyses (DFT, MESP, and FMO) were highly consistent with the biological activity. 1c possessed the highest electrophilicity index ( ω ), chemical potential ( μ ), and electron transfer capability (Δ N ), as well as the strongest electrophilic site ( V _{s ,max} ), which explains its superior biological activity. This study confirms the potent proangiogenic activity of chalcone derivative 1c, providing a promising lead compound for the development of novel small‐molecule therapeutics targeting vascular dysfunction diseases.

The therapeutic potential of adipose-derived mesenchymal stromal cells (ADSCs) in inflammatory bowel disease (IBD) is well established, yet the mechanisms

Radioresistance of adenocarcinoma cells limits the efficiency of radiotherapy. In addition to the cell nucleus, ionizing radiation (IR) also induces damage to the mitochondria. Mitophagy, a selective degradation of impaired mitochondria via autophagy, has been found to respond to IR, but its role in the radiosensitivity of adenocarcinoma cells remains unclear. Using several different adenocarcinoma cell lines, we confirmed that exposing the adenocarcinoma cells to 5 Gy X-ray enhanced the expression of some mitophagy receptors and increased mitophagy activity. However, pharmacological inhibition of mitophagy by mdivi-1 did not significantly change the radiosensitivity of HCT116 and A549 cells. Similarly, molecular targeting inhibition of mitophagy by BNIP3L knockdown in HCT116 and A549 cells that showed significant IR-induced BNIP3L up-regulation did also not significantly affect the radiosensitivity of adenocarcinoma cells, although the IR-induced enhancement of mitophagy activity was effectively suppressed. According to our data, mitophagy is responsible to IR but plays a very limited role in the radiosensitivity of adenocarcinoma cells. Further in vivo studies are warranted to elucidate the radiosensitizing effect of targeting mitophagy on malignant tumors.

We evaluated the growth‐inhibitory effects of three γ‐butyrolactam (γ‐lactam) derivatives (compounds 5, 6, and 8) on human breast cancer cells (MCF‐7) and in a xenografted chick model. Growth inhibition was assessed using MTT assays and flow cytometry for compounds 5, 6, and 8, followed by Western blot analysis to examine the expression levels of cell cycle‐associated proteins. Chick embryos were utilized as a xenograft model for further validation. The results revealed that compound 8 exhibited relatively low toxicity among the tested compounds. Western blot analysis suggested that compounds 5, 6, and 8 may be involved in the EGFR and P53 signaling pathways. In the xenograft model, compound 8 significantly inhibited MCF‐7 tumor growth in chick embryos (tumor size in control group: 1.97 ± 0.69 mm, n = 15; compound 8‐treated group: 1.20 ± 0.37 mm, n = 15). These findings suggest that compound 8 effectively inhibits MCF‐7 growth with minimal toxicity, warranting further investigation in mammalian models.