Chan, L. H. | bioRxiv Science

bioRxiv2022

WDR5 promotes breast cancer growth and metastasis via KMT2-independent translation regulation

Metastatic breast cancer remains a major cause of cancer related deaths in women and there are few effective therapies against this advanced disease. Emerging evidence suggests that key steps of tumor progression and metastasis are controlled by reversible epigenetic mechanisms. Using an in vivo genetic screen, we identified WDR5 as an actionable epigenetic regulator that is required for metastatic progression in models of triple-negative breast cancer. We found that knockdown of WDR5 in breast cancer cells independently impaired their tumorigenic as well as metastatic capabilities. Mechanistically, WDR5 promotes cell growth by increasing ribosomal gene expression and translation efficiency in a KMT2-independent manner. Consistently, pharmacological inhibition or degradation of WDR5 impedes cellular translation rate and the clonogenic ability of breast cancer cells. Furthermore, combination of WDR5-targeting with mTOR inhibitors leads to potent suppression of translation and proliferation of breast cancer cells. These results reveal novel therapeutic strategies to treat metastatic breast cancer.

cancer biology↗

bioRxiv2020

CECR2 Drives Breast Cancer Metastasis by Suppressing Macrophage Inflammatory Responses

Epigenetic and transcriptional changes are critical for metastasis, the major cause of cancer-related deaths. Metastatic tumor cells escape immune surveillance more efficiently than tumor cells in the primary sites, but the mechanisms controlling their immune evasion are poorly understood. We found that distal metastases are more immune inert with increased M2 macrophages compared to their matched primary tumors. Acetyl-lysine reader CECR2 is an epigenetic regulator upregulated in metastases and positively associated with M2 macrophages. CECR2 specifically promotes breast cancer metastasis in multiple mouse models, with more profound effect in the immunocompetent setting. Mechanistically, NF-{kappa}B family member RELA recruits CECR2 to activate CSF1 and CXCL1, which are critical for macrophage-mediated immunosuppression at the metastatic sites. Furthermore, pharmacological inhibition of CECR2 bromodomain impedes NF-{kappa}B-mediated immune suppression by macrophages and inhibits breast cancer metastasis. These results reveal novel therapeutic strategies to treat metastatic breast cancer. Statement of SignificanceComparison of matched primary breast tumors and distal metastases show that metastases are more immune inert with increased tumor promoting macrophages. Depletion or pharmacological inhibition of CECR2 inhibits breast cancer metastasis by suppressing macrophage inflammatory responses, nominating CECR2 as a promising therapeutic target for cancer metastasis.

cancer biology↗