Advances in highly active one-carbon metabolism in cancer diagnosis, treatment and drug resistance: A systematic review

Bioengineered Tumor-Stroma Prostate Cancer In Vitro Models for Screening Therapeutics

Cancer-associated fibroblasts are increasingly recognized to have a high impact on prostate tumor growth and drug resistance. Here, we bioengineered organotypic prostate cancer 3D in vitro models to better understand tumor-stroma interplay, the metabolomic profile underlying such interactions, and their impact on standard-of-care therapeutics performance. The assembly of robust and uniform spheroids was evaluated and compared in monotypic PC-3 and heterotypic microtumors comprised of either a healthy or malignant stroma and prostate cancer cells. Our findings demonstrate that the precise inclusion of prostate cancer stromal elements is crucial to generating robust PC-3 prostate cancer spheroids with reproducible morphology and size. The inclusion of cancer-associated fibroblasts promoted the establishment of more compact microtumors exhibiting characteristic expression of major proteins. Exometabolomic profile analysis also highlighted the impact of stromal cells on tumor models metabolism. The optimized heterotypic spheroids were additionally exploited for screening standard-of-care therapeutics, exhibiting a higher resistance when compared to their monotypic counterparts. Our findings demonstrate that including stromal elements in PC-3 prostate cancer models is crucial for their use as increasingly organotypic testing platforms, being relevant for screening candidate anti-cancer therapeutics and for the discovery of potential combinations with emerging anti-stroma therapies.

Metabolic Reprogramming in Cancer: Implications for Immunosuppressive Microenvironment

Cancer is a complex and heterogeneous disease characterised by uncontrolled cell growth and proliferation. One hallmark of cancer cells is their ability to undergo metabolic reprogramming, which allows them to sustain their rapid growth and survival. This metabolic reprogramming creates an immunosuppressive microenvironment that facilitates tumour progression and evasion of the immune system. In this article, we review the mechanisms underlying metabolic reprogramming in cancer cells and discuss how these metabolic alterations contribute to the establishment of an immunosuppressive microenvironment. We also explore potential therapeutic strategies targeting metabolic vulnerabilities in cancer cells to enhance immune-mediated anti-tumour responses. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02044861, NCT03163667, NCT04265534, NCT02071927, NCT02903914, NCT03314935, NCT03361228, NCT03048500, NCT03311308, NCT03800602, NCT04414540, NCT02771626, NCT03994744, NCT03229278, NCT04899921.

ZSWIM4 inhibition improves chemosensitivity in epithelial ovarian cancer cells by suppressing intracellular glycine biosynthesis

BACKGROUND

Zinc finger SWIM-type containing 4 (ZSWIM4) induces drug resistance in breast cancer cells. However, its role in epithelial ovarian cancer (EOC) remains unknown. In this study, we aimed to investigate the clinical significance of ZSWIM4 expression in EOC and develop new clinical therapeutic strategies for EOC.

METHODS

ZSWIM4 expression in control and EOC tumor tissues was examined using immunohistochemistry. Lentiviral transduction, Cell Counting Kit-8 assay, tumorsphere formation assay, flow cytometry, western blotting, and animal xenograft model were used to assess the role of ZSWIM4 in chemotherapy. Cleavage Under Targets and Tagmentation (CUT&Tag) assays, chromatin immunoprecipitation assays, and luciferase reporter assays were used to confirm FOXK1-mediated upregulation of ZSWIM4 expression. The mechanism by which ZSWIM4 inhibition improves chemosensitivity was evaluated using RNA-sequencing. A ZSWIM4-targeting inhibitor was explored by virtual screening and surface plasmon resonance analysis. Patient-derived organoid (PDO) models were constructed from EOC tumor tissues with ZSWIM4 expression.

RESULTS

ZSWIM4 was overexpressed in EOC tumor tissues and impaired patient prognoses. Its expression correlated positively with EOC recurrence. ZSWIM4 expression was upregulated following carboplatin treatment, which, in turn, contributed to chemoresistance. Silencing ZSWIM4 expression sensitized EOC cells to carboplatin treatment in vitro and in vivo. FOXK1 could bind to the GTAAACA sequence of the ZSWIM4 promoter region to upregulate ZSWIM4 transcriptional activity and FOXK1 expression increased following carboplatin treatment, leading to an increase in ZSWIM4 expression. Mechanistically, ZSWIM4 knockdown downregulated the expression of several rate-limiting enzymes involved in glycine synthesis, causing a decrease in intracellular glycine levels, thus enhancing intracellular reactive oxygen species production induced by carboplatin treatment. Compound IPN60090 directly bound to ZSWIM4 protein and exerted a significant chemosensitizing effect in both EOC cells and PDO models.

CONCLUSIONS

ZSWIM4 inhibition enhanced EOC cell chemosensitivity by ameliorating intracellular glycine metabolism reprogramming, thus providing a new potential therapeutic strategy for EOC.

One carbon metabolism and its implication in health and immune functions

One carbon (1C) metabolism is critical for cellular viability and physiological homeostasis. Starting from its crucial involvement in purine biosynthesis to posttranslational modification of proteins, 1C metabolism contributes significantly to the development and cellular differentiation through methionine and folate cycles that are pivotal for cellular function. Genetic polymorphisms of several genes of these pathways are implicated in disease pathogenesis and drug metabolism. Metabolic products of 1C metabolism have significant roles in epigenetic modifications through DNA and histone protein methylation. Homocysteine is a product that has clinical significance in the diagnosis and prognosis of several critical illnesses, including chronic immune diseases and cancers. Regulation of the function and differentiation of immune cells, including T-cells, B-cells, macrophages, and so forth, are directly influenced by 1C metabolism and thus have direct implications in several immune disease biology. Recent research on therapeutic approaches is targeting nuclear, cytoplasmic, and mitochondrial 1C metabolism to manage and treat metabolic (i.e., type 2 diabetes), neurodegenerative (i.e., Alzheimer's disease), or immune (i.e., rheumatoid arthritis) diseases. 1C metabolism is being explored for therapeutic intervention as a common determinant for a spectrum of immune and metabolic diseases. Identifying the association or correlation between essential metabolic products of this pathway and disease onset or prognosis would further facilitate the clinical monitoring of diseases.