Mitogen-Activated Protein Kinase and Exploratory Nuclear Receptor Crosstalk in Cancer Immunotherapy

Resveratrol contributes to NK cell-mediated breast cancer cytotoxicity by upregulating ULBP2 through miR-17-5p downmodulation and activation of MINK1/JNK/c-Jun signaling

BACKGROUNDS

Natural killer (NK) cell mediated cytotoxicity is a crucial form of anti-cancer immune response. Natural killer group 2 member D (NKG2D) is a prominent activating receptor of NK cell. UL16-binding protein 2 (ULBP2), always expressed or elevated on cancer cells, functions as a key NKG2D ligand. ULBP2-NKG2D ligation initiates NK cell activation and subsequent targeted elimination of cancer cells. Enhanced expression of ULBP2 on cancer cells leads to more efficient elimination of these cells by NK cells. Resveratrol (RES) is known for its multiple health benefits, while current understanding of its role in regulating cancer immunogenicity remains limited. This study aims to investigate how RES affects the expression of ULBP2 and the sensitivity of breast cancer (BC) cells to NK cell cytotoxicity, along with the underlying mechanisms.

METHODS

The effects of RES on ULBP2 expression were detected with qRT-PCR, western blot, flow cytometry analysis and immunohistochemistry. The effects of RES on sensitivity of BC cells to NK cell cytotoxicity were evaluated in vitro and in vivo. The target gene of miR-17-5p were predicted with different algorithms from five databases and further confirmed with dual-luciferase reporter assay. Overexpression and knockdown experiments of miR-17-5p and MINK1 were conducted to investigate their roles in regulating ULBP2 expression and subsequent JNK/c-Jun activation. The JNK inhibitor sp600125 was utilized to elucidate the specific role of JNK in modulating ULBP2 expression.

RESULTS

RES increased ULBP2 expression on BC cells, thereby augmenting their vulnerability to NK cell-mediated cytotoxicity both in vitro and in vivo. RES administration led to a reduction in cellular miR-17-5p level. MiR-17-5p negatively regulated ULBP2 expression. Specifically, miR-17-5p directly targeted MINK1, leading to its suppression. MINK1 played a role in facilitating the activation of JNK and its downstream effector, c-Jun. Furthermore, treatment with sp600125, a JNK inhibitor, resulted in the suppression of ULBP2 expression.

CONCLUSIONS：

RES potentiates ULBP2-mediated immune eradication of BC cells by NK cells through the downregulation of miR-17-5p and concurrent activation of the MINK1/JNK/c-Jun cascade. This finding identifies RES as a potentially effective therapeutic agent for inhibiting BC progression and optimizing NK cell-based cancer immunotherapy.

CRBN-PROTACs in Cancer Therapy: From Mechanistic Insights to Clinical Applications

Cereblon (CRBN), a member of the E3 ubiquitin ligase complex, has gained significant attention as a therapeutic target in cancer. CRBN regulates the degradation of various proteins in cancer progression, including transcription factors and signaling molecules. PROTACs (proteolysis-targeting chimeras) are a novel approach that uses the cell's degradation system to remove disease-causing proteins selectively. CRBN-dependent PROTACs work by tagging harmful proteins for destruction through the ubiquitin-proteasome system. This strategy offers several advantages over traditional protein inhibition methods, including the potential to overcome drug resistance. Recent progress in developing CRBN-based PROTACs has shown promising preclinical results in both hematologic malignancies and solid tumors. Additionally, CRBN-based PROTACs have enhanced our understanding of CRBN's role in cancer, potentially serving as biomarkers for patient stratification and predicting therapeutic responses. In this review, we delineate the mechanisms of action for CRBN-dependent PROTACs (CRBN-PROTACs), summarize recent advances in preclinical and clinical applications, and provide our perspective on future development.

Special Issue: MAPK Signaling Cascades in Human Health and Diseases

In order to survive and fulfil their functions, cells of any organism need to be able to respond to a large number of extracellular factors, also termed extracellular stimuli [...].

Network pharmacology-based research on the effect of Radix Astragali on osteosarcoma and the underlying mechanism

To explore the anti-tumor effects of Radix Astragali on osteosarcoma and its mechanism. We analyzed the PPI network of Radix Astragali's potential targets for treating osteosarcoma and got the hub targets. We used KM curves to screen hub targets that could prolong sarcoma patients' survival time. We performed GO and KEGG enrichment analysis of Radix Astragali's potential targets and predicted Radix Astragali's molecular mechanism and function in treating osteosarcoma. The binding process between the hub targets, which could prolong sarcoma patients' survival time, and Radix Astragali was simulated through molecular docking. PPI network analysis of potential therapeutic targets discriminated 25 hub targets. The KM curves of the hub targets showed there were 13 hub targets that were effective in improving the 5-year survival rate of sarcoma patients. GO and KEGG enrichment demonstrated that Radix Astragali regulates multiple signaling pathways of osteosarcoma. Molecular docking results indicated that Radix Astragali could bind freely to the hub target, which could prolong the sarcoma patient's survival time. Radix Astragali act on osteosarcoma by regulating a signaling network formed by hub targets connecting multiple signaling pathways. Radix Astragali has the potential to become a drug for treating osteosarcoma and prolonging the sarcoma patient's survival time.