Antineoplastic effects of pharmacological inhibitors of aurora kinases in CSF3RT618I-driven cells.

Myeloproliferative neoplasms (MPN) are consolidated as a relevant group of diseases derived from the malfunction of the hematopoiesis process and have as a particular attribute the increased proliferation of myeloid lineage. Among these, chronic neutrophilic leukemia (CNL) is distinguished, caused by the T618I mutation of the CSF3R gene, a trait that generates ligand-independent receptor activation and downstream JAK2/STAT signaling. Previous studies reported that mutations in BCR::ABL1 and JAK2V617F increased the expression of the aurora kinase A (AURKA) and B (AURKB) in Ba/F3 cells and their pharmacological inhibition displays antineoplastic effects in human BCR::ABL1 and JAK2V617F positive cells. Delimiting the current scenario, aspects related to the AURKA and AURKB as a potential target in CSF3RT618I-driven models is little known. In the present study, the cellular and molecular effects of pharmacological inhibitors of aurora kinases, such as aurora A inhibitor I, AZD1152-HQPA, and reversine, were evaluated in Ba/F3 expressing the CSF3RT618I mutation. AZD1152-HQPA and reversine demonstrated antineoplastic potential, causing a decrease in cell viability, clonogenicity, and proliferative capacity. At molecular levels, all inhibitors reduced histone H3 phosphorylation, aurora A inhibitor I and reversine reduced STAT5 phosphorylation, and AZD1152-HQPA and reversine induced PARP1 cleavage and γH2AX expression. Reversine more efficiently modulated genes associated with cell cycle and apoptosis compared to other drugs. In summary, our findings shed new insights into the use of AURKB inhibitors in the context of CNL.

Tartrolon D induces immunogenic cell death in melanoma.

Tartrolon D (TRL) is produced by Teredinibacter turnerae, a symbiotic cellulose-degrading bacteria in shipworm gills. Immunogenic cell death (ICD) induction contributes to a better and longer-lasting response to anticancer treatment. Tumor cells undergoing ICD trigger activation of the immune system, as a vaccine. AIMS: This study aimed to evaluate ICD induction by TRL. MAIN METHODS: Cell viability was evaluated by SRB assay. Cell stress, cell death, ICD features and antigen-presenting molecules were evaluated by flow cytometry and immunoblot. KEY FINDINGS: TRL showed antiproliferative activity on 7 tumor cell lines (L929, HCT 116, B16-F10, WM293A, SK-MEL-28, PC-3M, and MCF-7) and a non-tumor cell (HEK293A), with an inhibition concentration mean (IC50) ranging from 0.03 µM to 13 µM. Metastatic melanomas, SK-MEL-28, B16-F10, and WM293A, were more sensitive cell lines, with IC50 ranging from 0.07 to 1.2 µM. TRL induced apoptosis along with autophagy and endoplasmic reticulum stress and release of typical damage-associated molecular patterns (DAMPs) of ICD such calreticulin, ERp57, and HSP70 exposure, and HMGB1 release. Additionally, melanoma B16-F10 exposed to TRL increased expression of antigen-presenting molecules MHC II and CD1d and induced activation of splenocytes of C57BL/6 mice. SIGNIFICANCE: In spite of recent advances provided by target therapy and immunotherapy, advanced metastatic melanoma is incurable for more than half of patients. ICD inducers yield better and long-lasting responses to anticancer treatment. Our findings shed light on an anticancer candidate of marine origin that induces ICD in melanoma.

Characterization of 3D NSCLC Cell Cultures with Fibroblasts or Macrophages for Tumor Microenvironment Studies and Chemotherapy Screening.

The study of 3D cell culture has increased in recent years as a model that mimics the tumor microenvironment (TME), which is characterized by exhibiting cellular heterogeneity, allowing the modulation of different signaling pathways that enrich this microenvironment. The TME exhibits two main cell populations: cancer-associated fibroblasts (CAFs) and tumor-associated macrophages (TAM). The aim of this study was to investigate 3D cell cultures of non-small cell lung cancer (NSCLC) alone and in combination with short-term cultured dermal fibroblasts (FDH) and with differentiated macrophages of the THP-1 cell line. Homotypic and heterotypic spheroids were morphologically characterized using light microscopy, immunofluorescence and transmission electron microscopy. Cell viability, cycle profiling and migration assay were performed, followed by the evaluation of the effects of some chemotherapeutic and potential compounds on homotypic and heterotypic spheroids. Both homotypic and heterotypic spheroids of NSCLC were generated with fibroblasts or macrophages. Heterotypic spheroids with fibroblast formed faster, while homotypic ones reached larger sizes. Different cell populations were identified based on spheroid zoning, and drug effects varied between spheroid types. Interestingly, heterotypic spheroids with fibroblasts showed similar responses to the treatment with different compounds, despite being smaller. Cellular viability analysis required multiple methods, since the responses varied depending on the spheroid type. Because of this, the complexity of the spheroid should be considered when analyzing compound effects. Overall, this study contributes to our understanding of the behavior and response of NSCLC cells in 3D microenvironments, providing valuable insights for future research and therapeutic development.