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The increasing global cancer burden necessitates the development of new treatment options. Herbal medicine offers a viable alternative to conventional cancer treatments. Numerous studies have shown that 3-dimensional (3D) cell culture more accurately represents tumor characteristics in vivo. Therefore, this study utilized tumor spheroids to explore the therapeutic efficacy of emodin, a natural product-derived bioactive agent. We investigated differences in chemotherapeutic response between A549 cells cultured in 2D versus spheroids, assessing key factors influencing cancer progression, including apoptosis, cell proliferation, cell cycle, migration and invasion. The findings revealed that spheroid cells displayed increased resistance to emodin compared to cells cultured in 2D. Emodin exhibited a more pronounced cytostatic effect in 2D cells, while its cytotoxic effect was more prominent in spheroid cells. Moreover, emodin treatment diminished the migratory and invasive capabilities of the cells. Mechanistic investigations indicated that emodin triggered apoptosis in A549 cells via the mitochondrial apoptotic pathway. Emodin-treated cells exhibited a significant reduction in the phosphorylation of key cancer progression pathways, including JAK2, STAT3, FAK, and ERK, compared to untreated controls. Molecular docking analysis confirmed the interactions of emodin with JAK2 and FAK. These findings suggest that the JAK2/STAT3 and FAK/ERK signaling pathways may serve as critical drivers of the therapeutic effectiveness of emodin in A549 cells. • Spheroid cells showed higher resistance to emodin's effects than 2D cells. • Emodin displayed more potent cytostatic effects on 2D cells. • Emodin demonstrated stronger cytotoxic effects on spheroid cells. • Emodin induces A549 cell apoptosis through the mitochondrial apoptotic pathway. • The JAK2/STAT3 and FAK/ERK pathways could be critical to emodin's efficacy. [ABSTRACT FROM AUTHOR]

Multipotent stem cells are one of the most powerful tools available for the bone regeneration. However, owing to various limitations, including a lack of tissue-specific stem cell identification, reconstruction of large cranial bone defects remains challenging. In the current study, we isolated a population of Sca-1 + CD105 + CD140a + stem cells from adult mouse calvarium and cultured them as three-dimensional spheroids. Although these cells shared similar surface antigens when grown in either monolayers or spheroids, the cranial stem cells grown in spheroids possessed enhanced multipotency and proliferation capacity. In addition, the cranial stem cells in spheroids were found to express high levels of the self-renewal transcription factors Nanog , Oct-4 , and Sox-2 . Mechanistically, we found that three-dimensional spheroid culture suppressed NF-κB pathways, but activated the PI3K/AKT pathway in cranial stem cells. More importantly, activation of NF-κB pathways or specific inhibition of the PI3K/AKT pathway partially impaired spheroid formation and suppressed expression of self-renewal transcription factors. In summary, these findings reveal a novel effect of spheroid culture in promoting the maintenance of cranial stem cell stemness and indicate that NF-κB and PI3K/AKT pathways might be involved in the stemness maintenance. [ABSTRACT FROM AUTHOR]

Transcription factor GATA-6 plays a key role in normal cell differentiation of the mesoderm and endoderm. On the other hand, GATA-6 is abnormally overexpressed in many clinical gastrointestinal cancer tissue samples, and accelerates cell proliferation or an anti-apoptotic response in cancerous tissues. We previously showed that activation of the JNK signaling cascade causes proteolysis of GATA-6. In this study, we demonstrated that anisomycin, a JNK activator, stimulates nuclear export of GATA-6 in a colorectal cancer cell line, DLD-1. Concomitantly, anisomycin remarkably inhibits the proliferation of DLD-1 cells via G2/M arrest in a plate culture. However, it did not induce apoptosis under growth arrest conditions. Furthermore, the growth of DLD-1 cells in a spheroid culture was suppressed by anisomycin. Although 5-FU showed only a slight inhibitory effect on 3D spheroid cultures, the same concentration of 5-FU together with a low concentration of anisomycin exhibited strong growth inhibition. These results suggest that the induction of GATA-6 dysfunction may be more effective for chemotherapy for colorectal cancer, although the mechanism underlying the synergistic effect of 5-FU and anisomycin remains unknown. [ABSTRACT FROM AUTHOR]

Multiple cell–cell interactions control bone morphogenesis and vascularization. We have employed a spheroidal coculture system of endothelial cells (EC) and osteoblasts (OB) to study cell contact-dependent gene regulation between these two cell types that may play a role in regulating OB differentiation and EC angiogenic properties. Coculture spheroids differentiate spontaneously to organize into a core of OB and a surface layer of endothelial cells. Individual spheroid culture of EC or OB leads to significant alterations in gene expression compared to standard monolayer culture (upregulation of Tie-2 in EC; upregulation of angiopoietin-2 in osteoblasts). More importantly, spheroidal coculture of endothelial cells and osteoblasts leads to significant changes of gene expression in both cell populations (upregulation of VEGFR-2 in EC; downregulation of VEGF, and upregulation of alkaline phosphatase in osteoblasts). These changes are dependent on cell–cell contact and are not seen in stimulation experiments with conditioned supernatants. Collectively, the data demonstrate complex bi-directional gene regulation mechanisms between EC and OB that are likely to play a critical role during OB differentiation and in controlling the properties of angiogenic EC. [Copyright &y& Elsevier]