ACT-001(Accendatech)

Parthenolide is confirmed to be an important component of the anticancer drug-ACT001. However, parthenolide biosynthesis in Saccharomyces cerevisiae (S. cerevisiae) was greatly hindered by the low conversion rate of its precursor, costunolide. In this study, the Position Specific Scoring Matrix (PSSM) was used to analyze the sequence evolutionary information of parthenolide synthase from Tanacetum parthenium (TpPTS), and a series of mutants were designed and validated. Notably, when the mutant of TpPTS-Y22G was introduced in S. cerevisiae, the parthenolide titer increased by 110 % compared to that of the TpPTS wild-type. Considering TpPTS as an endoplasmic reticulum-localized cytochrome P450 and the importance of heme supply, endoplasmic-associated molecular chaperone HRD1 (hydroxymethyl glutaryl-coenzyme A reductase degradation protein 1) and heme biosynthesis gene HEM2 (aminolevulinate dehydratase) were overexpressed in S. cerevisiae to improve TpPTS expression and catalytic activity. As a result, a titer of 27.08 mg/L parthenolide was achieved in a shake flask, which was further increased by 209 %. Additionally, the conversion rate of costunolide to parthenolide increased from 20.4 % to 51.8 % compared to the initial strain yYTQ001. Eventually, a parthenolide titer of 99.71 mg/L was achieved in a 5-L bioreactor. Our research provides effective strategies and valuable references for engineering rate-limiting cytochrome P450 enzymes to improve sesquiterpenes production in S. cerevisiae.

Temozolomide (TMZ), which is an alkylating agent, is the standard chemotherapeutic drug used for glioma treatment. However, the development of resistance to TMZ limits its efficacy. Thus, identifying novel therapeutic targets is necessary.

In this study, the levels of midkine (MDK) and c‐Myc expression in glioma patient samples downloaded from TCGA were analyzed. Their interactions were also demonstrated through microthermometry and immunocoprecipitation. Furthermore, proteomics technology and Western blot showed that MDK interacted with c‐Myc and influenced its ubiquitination, thereby activating a prosurvival signalling pathway and epithelial–mesenchymal transition mechanism, which contributed to TMZ resistance. To target the MDK/c‐Myc complex, we screened for a small‐molecule inhibitor (ACT001) that specifically disrupts the interaction between MDK and c‐Myc. Treatment with ACT001 greatly sensitized TMZ‐resistant glioma cells to TMZ, promoting cell death and inhibiting cell proliferation. Moreover, combination therapy with ACT001 and TMZ showed synergistic effects that inhibit tumour growth in glioma xenograft models and glioma in situ models.

ACT001 facilitated the degradation of c‐Myc by focusing on the MDK/c‐Myc complex and controlled the Wnt/β‐catenin signalling pathway via MDK, ultimately halting the advancement of glioma. When combined with TMZ, ACT001 showed good therapeutic potential for the treatment of glioma.

Focusing on the MDK/c‐Myc complex could be an effective approach to combat resistance to TMZ in glioma. Therapy with ACT001 may be a novel approach to improve the efficacy of TMZ‐based chemotherapy in patients with glioma. Further preclinical and clinical studies are warranted to validate the therapeutic potential of targeting the MDK/c‐Myc complex in glioma treatment.