Olaparib Synergizes the Anticancer Activity of Daunorubicin via Interaction with AKR1C3

Adipocyte maturation impacts daunorubicin disposition and metabolism

INTRODUCTION

Acute lymphoblastic leukaemia (ALL) is the most common type of childhood leukaemia with effective chemotherapeutic treatment. However, obesity has been associated with higher ALL chemoresistance rates and lower event-free survival rates. The molecular mechanism of how obesity promotes chemotherapy resistance is not well delineated.

OBJECTIVES

This study evaluated the effect of adipocyte maturation on sequestration and metabolism of chemotherapeutic drug daunorubicin (DNR).

METHODS

Using targeted LC-MS/MS multi-analyte assay, DNR sequestration and metabolism were studied in human preadipocyte and adipocyte cell lines, where expressions of DNR-metabolizing enzymes aldo-keto reductases (AKR) and carbonyl reductases (CBR) were also evaluated. In addition, to identify the most DNR-metabolizing AKR/CBR isoforms, recombinant human AKR and CBR enzymes were subject to DNR metabolism. The results were further validated by AKR-, CBR-specific inhibitors.

RESULTS

This report shows that adipocyte maturation upregulates expressions of AKR and CBR enzymes (by 4- to 60- folds, p < .05), which is positively associated with enhanced sequestration and metabolism of DNR in adipocytes compared to preadipocytes (by ~30%, p < .05). In particular, adipocyte maturation upregulates AKR1C3 and CBR1, which are the predominate metabolic enzyme isoforms responsible for DNR biotransformation to its metabolites.

CONCLUSION

Fat is an expandable tissue that can sequester and detoxify DNR when stimulated by obesity, likely through the upregulation of DNR-metabolizing enzymes AKR1C3 and CBR1. Our data partially explains why obese ALL patients may be more likely to become chemoresistant towards DNR, and provides evidence for potential clinical investigation targeting obesity to reduce DNR chemoresistance.

AKR1C3 in carcinomas: from multifaceted roles to therapeutic strategies

Aldo-Keto Reductase Family 1 Member C3 (AKR1C3), also known as type 5 17β-hydroxysteroid dehydrogenase (17β-HSD5) or prostaglandin F (PGF) synthase, functions as a pivotal enzyme in androgen biosynthesis. It catalyzes the conversion of weak androgens, estrone (a weak estrogen), and PGD2 into potent androgens (testosterone and 5α-dihydrotestosterone), 17β-estradiol (a potent estrogen), and 11β-PGF2α, respectively. Elevated levels of AKR1C3 activate androgen receptor (AR) signaling pathway, contributing to tumor recurrence and imparting resistance to cancer therapies. The overexpression of AKR1C3 serves as an oncogenic factor, promoting carcinoma cell proliferation, invasion, and metastasis, and is correlated with unfavorable prognosis and overall survival in carcinoma patients. Inhibiting AKR1C3 has demonstrated potent efficacy in suppressing tumor progression and overcoming treatment resistance. As a result, the development and design of AKR1C3 inhibitors have garnered increasing interest among researchers, with significant progress witnessed in recent years. Novel AKR1C3 inhibitors, including natural products and analogues of existing drugs designed based on their structures and frameworks, continue to be discovered and developed in laboratories worldwide. The AKR1C3 enzyme has emerged as a key player in carcinoma progression and therapeutic resistance, posing challenges in cancer treatment. This review aims to provide a comprehensive analysis of AKR1C3's role in carcinoma development, its implications in therapeutic resistance, and recent advancements in the development of AKR1C3 inhibitors for tumor therapies.

In Silico and In Vitro Assessment of Carbonyl Reductase 1 Inhibition Using ASP9521-A Potent Aldo-Keto Reductase 1C3 Inhibitor with the Potential to Support Anticancer Therapy Using Anthracycline Antibiotics

Anthracycline antibiotics (ANT) are among the most widely used anticancer drugs. Unfortunately, their use is limited due to the development of drug resistance and cardiotoxicity. ANT metabolism, performed mainly by two enzymes-aldo-keto reductase 1C3 (AKR1C3) and carbonyl reductase 1 (CBR1)-is one of the proposed mechanisms generated by the described effects. In this study, we evaluated the CBR1 inhibitory properties of ASP9521, a compound already known as potent AKR1C3 inhibitor. First, we assessed the possibility of ASP9521 binding to the CBR1 catalytic site using molecular docking and molecular dynamics. The research revealed a potential binding mode of ASP9521. Moderate inhibitory activity against CBR1 was observed in studies with recombinant enzymes. Finally, we examined whether ASP9521 can improve the cytotoxic activity of daunorubicin against human lung carcinoma cell line A549 and assessed the cardioprotective properties of ASP9521 in a rat cardiomyocytes model (H9c2) against doxorubicin- and daunorubicin-induced toxicity. The addition of ASP9521 ameliorated the cytotoxic activity of daunorubicin and protected rat cardiomyocytes from the cytotoxic effect of both applied drugs. Considering the favorable bioavailability and safety profile of ASP9521, the obtained results encourage further research. Inhibition of both AKR1C3 and CBR1 may be a promising method of overcoming ANT resistance and cardiotoxicity.

Bruton’s Tyrosine Kinase Inhibitor Zanubrutinib Effectively Modulates Cancer Resistance by Inhibiting Anthracycline Metabolism and Efflux

Zanubrutinib (ZAN) is a Bruton’s tyrosine kinase inhibitor recently approved for the treatment of some non-Hodgkin lymphomas. In clinical trials, ZAN is often combined with standard anthracycline (ANT) chemotherapy. Although ANTs are generally effective, drug resistance is a crucial obstacle that leads to treatment discontinuation. This study showed that ZAN counteracts ANT resistance by targeting aldo-keto reductase 1C3 (AKR1C3) and ATP-binding cassette (ABC) transporters. AKR1C3 catalyses the transformation of ANTs to less potent hydroxy-metabolites, whereas transporters decrease the ANT-effective concentrations by pumping them out of the cancer cells. In our experiments, ZAN inhibited the AKR1C3-mediated inactivation of daunorubicin (DAUN) at both the recombinant and cellular levels. In the drug combination experiments, ZAN synergistically sensitised AKR1C3-expressing HCT116 and A549 cells to DAUN treatment. Gene induction studies further confirmed that ZAN did not increase the intracellular level of AKR1C3 mRNA; thus, the drug combination effect is not abolished by enzyme induction. Finally, in accumulation assays, ZAN was found to interfere with the DAUN efflux mediated by the ABCB1, ABCG2, and ABCC1 transporters, which might further contribute to the reversal of ANT resistance. In summary, our data provide the rationale for ZAN inclusion in ANT-based therapy and suggest its potential for the treatment of tumours expressing AKR1C3 and/or the above-mentioned ABC transporters.

Discovery of Novel Aldo-Keto Reductase 1C3 Inhibitors as Chemotherapeutic Potentiators for Cancer Drug Resistance

As a crucial target which is overexpressed in a variety of cancers, aldo-keto reductase 1C3 (AKR1C3) confers chemotherapeutic resistance to many clinical agents. However, a limited number of AKR1C3-selective inhibitors are applied clinically, which indicates the importance of identifying active compounds. Herein, we report the discovery, synthesis, and evaluation of novel and potent AKR1C3 inhibitors with structural diversity. Molecular dynamics simulations of these active compounds provide reasonable clarification of the interpreted biological data. Moreover, we demonstrate that AKR1C3 inhibitors have the potential to be superior therapeutic agents for re-sensitizing drug-resistant cell lines to chemotherapy, especially the pan-AKR1C inhibitor S07-2010. Our study identifies new structural classes of AKR1C3 inhibitors and enriches the structural diversity, which facilitates the future rational design of inhibitors and structural optimization. Moreover, these compounds may serve as promising therapeutic adjuvants toward new therapeutics for countering drug resistance.

Roles of CYP3A4, CYP3A5 and CYP2C8 drug-metabolizing enzymes in cellular cytostatic resistance

Metabolic deactivation by cytochrome P450 (CYP) is considered a potential mechanism of anticancer drug resistance. However, this hypothesis is predominantly based on indirect pieces of evidence and/or is influenced by interfering factors such as the use of multienzymatic models. Thus, an experimental approach for its verification is needed. In the present work, we employed HepG2 cells transduced with CYP enzymes involved in docetaxel, paclitaxel and vincristine metabolism to provide mechanistic evidence on their possible roles in resistance to these chemotherapeutic agents. Using MTT proliferation tests, we showed that overexpression of CYP3A4 resulted in decreased antiproliferative activity of 1 μM docetaxel (by 11.2, 23.2 and 22.9% at 24, 48 and 72 h intervals, respectively), while the sensitivity of CYP3A4-transduced cells was restored by co-administration of ketoconazole. Paclitaxel exhibited differential efficacy in CYP2C8- and empty vector-transduced cells (significant differences between 10.9 and 24.4% for 0.01, 0.1 and 1 μM concentrations), but neither montelukast nor clotrimazole was capable of affecting this asymmetry. Finally, the pharmacological activity of vincristine was not influenced by CYP3A4 or CYP3A5 overexpression. In the follow-up caspase activation assays, docetaxel was confirmed to be a victim of CYP3A4-mediated resistance, which is, at least partly, brought by impaired activation of caspases 3/7, 8 and 9. In summary, our data demonstrate that CYP3A4-mediated metabolic deactivation of docetaxel might represent a significant mechanism of pharmacokinetic resistance to this drug. In contrast, the possible role of CYPs in resistance to paclitaxel and vincristine has been disconfirmed. Importantly, the expression of CYP3A4 in HepG2_CYP3A4 cells is comparable to that in primary hepatocytes and HepaRG cells, which suggests that our results might be relevant for in vivo conditions, e.g., for hepatocellular carcinoma. Thus, our data may serve as a valuable in vitro background for future in vivo studies exploring the area of intratumoural metabolism-based drug resistance.