Bis-indole-derived NR4A1 antagonists inhibit colon tumor and splenic growth and T-cell exhaustion. Academic Article uri icon

abstract

  • There is evidence that the orphan nuclear receptor 4A1 (NR4A1, Nur77) is overexpressed in exhausted CD8 + T cells and regulates PD-L1 in tumors. This study investigated the effects of potent bis-indole-derived NR4A1 antagonists on reversing T-cell exhaustion and downregulating PD-L1 in colon tumors/cells. NR4A1 antagonists inhibited colon tumor growth and downregulated expression of PD-L1 in mouse colon MC-38-derived tumors and cells. TILs from MC-38 cell-derived colon tumors and splenic lymphocytes exhibited high levels of the T-cell exhaustion markers including PD-1, 2B4, TIM3+ and TIGIT and similar results were observed in the spleen, and these were inhibited by NR4A1 antagonists. In addition, treatment with NR4A1 antagonists induced cytokine activation markers interferon , granzyme B and perforin mRNAs and decreased TOX, TOX2 and NFAT in TIL-derived CD8 + T cells. Thus, NR4A1 antagonists decrease NR4A1-dependent pro-oncogenic activity and PD-L1 expression in colon tumors and inhibit NR4A1-dependent T-cell exhaustion in TILs and spleen and represent a novel class of mechanism-based drugs that enhance immune surveillance in tumors.

published proceedings

  • Cancer Immunol Immunother

author list (cited authors)

  • Mohankumar, K., Wright, G., Kumaravel, S., Shrestha, R., Zhang, L., Abdelrahim, M., Chapkin, R. S., & Safe, S.

complete list of authors

  • Mohankumar, Kumaravel||Wright, Gus||Kumaravel, Subhashree||Shrestha, Rupesh||Zhang, Lei||Abdelrahim, Maen||Chapkin, Robert S||Safe, Stephen

publication date

  • October 2023