P1, N=35, Active, not recruiting, M.D. Anderson Cancer Center | Trial completion date: Jul 2025 --> Jul 2027 | Trial primary completion date: Jul 2025 --> Jul 2027

This reduces p53 degradation and consequently activates p53, leading to p21 transcription and the induction of cellular senescence. Treatment with doxorubicin (Dox) or nutlin-3a further enhances p53-mediated transcriptional activation of p21, and their combination with LTβR depletion exerts an additive effect in promoting cellular senescence.

Further, DPMI-ω inhibited B16 melanoma growth in vivo and, when combined with an anti-PD1 antibody, powerfully augmented the efficacy of immunotherapy by expanding CD3+/CD8+ cytotoxic T cells and suppressing CD4+/CD25+ regulatory T cells. Our work validates the design of a therapeutically viable anticancer peptide, showcasing its potential in combination therapy to treat patients with tumors that are otherwise resistant or poorly responsive to antitumor immunotherapy.

We demonstrated that a mtp53-MDM2/MDMX complex promoted 53BP1-MDC1 interactions by showing that mtp53-MDM2/MDMX complex disruptors, Nutlin 3a and ALRN-6924, reduced the 53BP1-MDC1 nuclear interactions (especially in S-phase)...We found that MDM2-deficient cells have increased poly-ADP-ribosylation on chromatin which supports the possibility that a mtp53-MDM2/MDMX pathway promotes aberrant DNA repair. Taken together, our data suggest that a mtp53-MDM2/MDMX complex orchestrates DNA repair machinery activity on chromatin, thus priming cancer cells for persistent DNA damage repair (CPR).

Moreover, we found that MDMX Ser-314 phosphorylation, a consensus sequence of CDK4/6, increases MDMX stability, which subsequently affects MDM2 and p53 degradation and could be reversed by the CDK4/6 inhibitor Palbociclib...Consequently, p53 inactivation promotes their survival, proliferation, and resistance to chemotherapy-induced apoptosis. The figure was created in BioRender.com.

This study reveals that Mdmx can control cell invasion through RhoA stabilisation/activation, which is potentially linked to the reported anti-oncogenic functions of Mdmx. As inhibitors of the NEDD8 pathway are in clinical trials, the status of Mdmx may be a critical determinant for the anti-tumour effects of these inhibitors.

This review introduces the structure, distribution, and regulation of the MDMX, summarizes the structural features and structure-activity relationships (SARs) of MDMX ligands, and focuses on the differences between MDMX and MDM2 in these aspects. Our purpose of this work is to propose potential strategies to achieve the specific targeting of MDMX.

P1, N=35, Active, not recruiting, M.D. Anderson Cancer Center | Phase classification: P1b --> P1

In conclusion, miR-34c-5p was down-regulated in BAS and may inhibit fibroblast proliferation differentiation and EMT in BAS via the MDMX/p53 signaling axis. These findings expand the understanding of the role of miR-34c-5p and will help develop new treatment strategies for BAS.

P1, N=84, Not yet recruiting, Roswell Park Cancer Institute

CCDC106 overexpression downregulates the cellular level of p53 and Mdm2/MdmX, and decreased p53 reversibly downregulates the cellular level of CCDC106. Our work provides a molecular mechanism by which CCDC106 regulates the cellular levels of p53 and Mdm2/MdmX.

P1b, N=35, Active, not recruiting, M.D. Anderson Cancer Center | Trial completion date: Jul 2023 --> Apr 2025 | Trial primary completion date: Jul 2023 --> Apr 2025