Engineering aldo-keto reductase 1B10 to mimic the distinct 1B15 topology and specificity towards inhibitors and substrates, including retinoids and steroids

AKR1B10 and digestive tumors development: a review

Aldo-keto reductase family 1 member B10 (AKR1B10) is a member of the AKR1B subfamily. It is mainly found in cytoplasm, and it is typically expressed in the stomach and intestines. Given that its expression is low or absent in other tissues, AKR1B10 is a potential diagnostic and therapeutic biomarker for various digestive system diseases. Here, we review recent research progress on AKR1B10 in digestive system tumors such as hepatocellular carcinoma, gastric carcinoma, colorectal carcinoma, pancreatic carcinoma, oral squamous cell carcinoma, laryngeal squamous cell carcinoma, cholangiocarcinoma, and nasopharyngeal carcinoma, over the last 5 years. We also discuss the current trends and future research directions for AKR1B10 in both oncological and non-oncological diseases to provide a scientific reference for further exploration of this gene.

The pan-cancer landscape of aldo-keto reductase1B10 reveals that its expression is diminished in gastric cancer

Introduction

Aldo-keto reductase 1B10 (AKR1B10) is a multifunctional enzyme, which is important in cancer development and progression, but the landscape of AKR1B10 in pan-cancers and in tumor microenvironment is unclear.

Method

This study integrated the sequencing data of 33 cancer types, including gastric cancer, from TCGA project to explored the expression pattern and genetic and epigenetic alterations of AKR1B10. The association of AKR1B10 expression with clinical progression of cancers was evaluated by Kaplan-Meier analysis; the potential role of AKR1B10 in tumor microenvironment (TME) and immune-related gene expression were analyzed by PURITY, ESTIMATE, TIMER and CIBERSORT algorithms. The expression of AKR1B10 and immune cell markers in gastric cancer were evaluated with multiplex immunofluorescence staining.

Result

Results indicated that AKR1B10 was highly expressed in the gastrointestinal tract in health donors, but the expression of AKR1B10 was significantly changed in most of cancer types, which may be ascribed to DNA methylation in its promoter. The AKR1B10 expression in cancers and its value in disease progression was bidirectional and functionally enriched in metabolism in pan-cancers. In tumor microenvironment, AKR1B10 was significantly correlated with immune cell infiltrations and immune gene expression. In the stomach, along with the diminishing of AKR1B10 expression, CD68+ macrophage increased and CD19+ B cell decreased in gastric cancer.

Discussion

These data indicates that AKR1B10 may be an important factor in the development and progression and a potential therapeutic target for multiple cancers, but plays as a protector in the gastric tissues.

Repurposing of Strychnine as the Potential Inhibitors of Aldo-keto Reductase Family 1 Members B1 and B10: Computational Modeling and Pharmacokinetic Analysis

AKR1B1 and AKR1B10 are important members of aldo-keto reductase family which plays a significant role in cancer progression by modulating cellular metabolism. These enzymes are involved in various metabolic processes, including the synthesis and metabolism of hormones, detoxification of reactive aldehydes, and the reduction of various endogenous and exogenous compounds. This study aimed to explore the potential of strychnine as an anticancer agent by targeting AKR1B1 and AKR1B10 via drug repurposing approach. To assess the drug-like properties of strychnine, a physiologically based pharmacokinetic (PKPB) model and High Throughput Pharmacokinetics (HTPK) approach were employed. The obtained results fell within the expected range for drug molecules, confirming its suitability for further investigation. Additionally, density functional theory (DFT) studies were conducted to gain insight into the electronic properties contributing to the drug molecule's reactivity. Building upon the promising DFT results, molecular docking analysis using the AutoDock tool was performed to examine the binding interactions between strychnine and the proposed targets, AKR1B1 and AKR1B10. Findings from the molecular docking studies suggested a higher probability of strychnine acting as an inhibitor of AKR1B1 and AKR1B10 with docking scores of - 30.84 and - 29.36 kJ/mol respectively. To validate the stability of the protein-ligand complex, Molecular Dynamic Simulation (MDS) studies were conducted, revealing the formation of a stable complex between the enzymes and strychnine. This comprehensive approach sheds light on the potential effectiveness of strychnine as a treatment for breast, lung, liver, and pancreatic cancers, as well as related malignancies. The novel insights gained from the physiologically based pharmacokinetic modeling, density functional theory, molecular docking, and molecular dynamics simulations collectively support the prospect of strychnine as a promising molecule for anticancer therapy. Further investigations are warranted to validate these findings and explore the therapeutic potential of strychnine in preclinical and clinical settings.

FNDC5 and AKR1B10 inhibit the proliferation and metastasis of adrenocortical carcinoma cells by regulating AMPK/mTOR pathway

Being a rare malignancy, adrenocortical carcinoma (ACC) exhibits aggressiveness and poor prognosis. Fibronectin type III domain-containing protein 5 (FNDC5) is a transmembrane protein involved in multiple types of cancer. Aldo-keto reductase family 1 member B10 (AKR1B10) has a suppressive role in ACC. The present study aimed to investigate the role of FNDC5 in ACC cells as well as its mechanisms related to AKR1B10. The Gene Expression Profiling Interactive Analysis database predicted FNDC5 expression in tumour tissue of patients suffering from ACC and the overall survival rate. Western blotting as well as reverse transcription-quantitative PCR were used for the examination of the transfection efficiency of FNDC5-overexpression vector (Oe-FNDC5) and small interfering (si)RNA against AKR1B10. Cell Counting Kit-8 was employed for the assessment of cell viability. The proliferation, migration and invasion of the transfected cells were assessed by 5-ethynyl-2'-deoxyuridine staining, wound healing and Transwell assays. Additionally, cell apoptosis was evaluated by flow cytometry and caspase-3 activity was determined by ELISA. The levels of epithelial-mesenchymal transition- and 5'-AMP-activated protein kinase (AMPK)/mTOR signalling pathway-associated proteins were assessed by western blotting. The interaction between FNDC5 and AKR1B10 was confirmed by co-immunoprecipitation. FNDC5 levels in ACC tissue were reduced compared with normal tissue. After overexpressing FNDC5, proliferation, migration and invasion of NCI-H295R cells were suppressed, while cell apoptosis was promoted. FNDC5 interacted with AKR1B10 and AKR1B10 knockdown promoted proliferation, migration and invasion while inhibiting the apoptosis of NCI-H295R cells transfected with si-AKR1B10. The AMPK/mTOR signalling pathway was activated by FNDC5 overexpression, which was subsequently suppressed by AKR1B10 knockdown. Collectively, FNDC5 overexpression inhibited proliferation, migration and invasion while promoting apoptosis of NCI-H295R cells via triggering the AMPK/mTOR signalling pathway. These effects were counteracted by AKR1B10 knockdown.

Gender dimorphism in survival of patients with lymph node metastasis of bladder cancer

Background:

The effect of gender on the prognosis of bladder cancer (BCa) in different metastatic sites is insufficiently understood. We aimed to assess the impact and potential mechanisms of a combination of gender dimorphism and BCa metastasis sites on the risk of death.

Methods:

Independent predictors of overall survival and cancer-specific survival were analyzed after stratification by gender and metastasis sites from the Surveillance, Epidemiology, and End Results database. Furthermore, gender-differentially expressed genes (DEGs) and function-enriched annotations for patients with lymph node metastasis (LNM) were identified from The Cancer Genome Atlas (TCGA) database. A gender-associated signature was constructed in TCGA and validated in the IMvigor210 trial, and the magnetic resonance imaging-based radiomics signature was developed in our center to predict the gender-associated signature.

Results:

In patients with metastatic BCa, the most common site of metastasis is bone in men and lung in women. Moreover, stratified by sex, LNM had a better prognosis in men than visceral metastasis, which was not observed in female. Similarly, stratified by the metastasis site, the prognosis of men in patients with LNM is better than that of women, which was not observed in visceral metastasis patients. Enrichment of DEGs between sexes in patients with LNM may be related to metastasis and tumor immunity, especially the role of neutrophils. Moreover, the gender-associated signature is related to the clinicopathological characteristics of patients, and patients in the high-risk group had worse survival outcomes, and higher susceptibility to cisplatin, docetaxel, camptothecin, and paclitaxel. A nomogram combined with the signature and clinical staging showed significant predictive power in survival prediction. Furthermore, patients with high radiomics scores had a strong tendency for high-risk group.

Conclusion:

These results may improve the understanding of the differences in tumor biology between sexes and thus provide additional evidence for individualized treatment in BCa.

The Role of AKR1B10 in Physiology and Pathophysiology

AKR1B10 is a human nicotinamide adenine dinucleotide phosphate (NADPH)-dependent reductase belonging to the aldo-keto reductase (AKR) 1B subfamily. It catalyzes the reduction of aldehydes, some ketones and quinones, and interacts with acetyl-CoA carboxylase and heat shock protein 90α. The enzyme is highly expressed in epithelial cells of the stomach and intestine, but down-regulated in gastrointestinal cancers and inflammatory bowel diseases. In contrast, AKR1B10 expression is low in other tissues, where the enzyme is upregulated in cancers, as well as in non-alcoholic fatty liver disease and several skin diseases. In addition, the enzyme's expression is elevated in cancer cells resistant to clinical anti-cancer drugs. Thus, growing evidence supports AKR1B10 as a potential target for diagnosing and treating these diseases. Herein, we reviewed the literature on the roles of AKR1B10 in a healthy gastrointestinal tract, the development and progression of cancers and acquired chemoresistance, in addition to its gene regulation, functions, and inhibitors.

Synthesis of C11-to-C14 methyl-shifted all-trans-retinal analogues and their activities on human aldo-keto reductases

Human aldo-keto reductases (AKRs) are enzymes involved in the reduction, among other substrates, of all-trans-retinal to all-trans-retinol (vitamin A), thus contributing to the control of the levels of retinoids in organisms. Structure-activity relationship studies of a series of C11-to-C14 methyl-shifted (relative to natural C13-methyl) all-trans-retinal analogues as putative substrates of AKRs have been reported. The synthesis of these retinoids was based on the formation of a C10-C11 single bond of the pentaene skeleton starting from a trienyl iodide and the corresponding dienylstannanes and dienylsilanes, using the Stille-Kosugi-Migita and Hiyama-Denmark cross-coupling reactions, respectively. Since these reagents differ by the location and presence of methyl groups at the dienylorganometallic fragment, the study also provided insights into the ability of the different positional isomers to undergo cross-coupling and the sensitivity of these processes to steric hindrance. The resulting C11-to-C14 methyl-shifted all-trans-retinal analogues were found to be active substrates when tested with AKR1B1 and AKR1B10 enzymes, although relevant differences in substrate specificities were noted. For AKR1B1, all analogues exhibited higher catalytic efficiency (kcat/Km) than parent all-trans-retinal. In addition, only all-trans-11-methylretinal, the most hydrophobic derivative, showed a higher value of kcat/Km = 106 000 ± 23 200 mM-1 min-1 for AKR1B10, which is in fact the highest value from all known retinoid substrates of this enzyme. The novel structures, identified as efficient AKR substrates, may serve in the design of selective inhibitors with potential pharmacological interest.

AKR1B10 Inhibitor Epalrestat Facilitates Sorafenib-Induced Apoptosis and Autophagy Via Targeting the mTOR Pathway in Hepatocellular Carcinoma

Sorafenib is the standard systemic treatment for advanced hepatocellular carcinoma (HCC), and improving its therapeutic effects is crucial for addressing cancer aggression. We previously reported that epalrestat, an aldo-keto reductase 1B10 inhibitor, enhanced sorafenib's inhibitory effects on HCC xenograft in nude mice. This study aimed to elucidate the mechanism of epalrestat's anti-tumour enhancing effects on sorafenib. HepG2 cells were treated with sorafenib, epalrestat, and their combination. Cell proliferation was assessed with Cell Counting Kit-8 and colony formation assays. AKR1B10 supernate concentration and enzyme activity were detected by ELISA assay and the decrease of optical density of NADPH at 340 nm. Cell cycle and apoptosis analyses were performed with flow cytometry. Western blots clarified the molecular mechanism underlying effects on cell cycle, apoptosis, and autophagy. The anti-tumour mechanism was then validated in vivo through TUNEL and immunohistochemistry staining of HCC xenograft sections. Epalrestat combined with sorafenib inhibited HepG2 cellular proliferation in vitro, arrested the cell cycle at G0/G1, and promoted apoptosis and autophagy. Treatment with a specific mTOR activator MHY-1485 increased mTOR phosphorylation, while suppressing apoptosis and autophagy. Consistent with in vitro results, data from the HCC-xenograft nude mouse model also indicated that combined treatment inhibited the mTOR pathway and promoted apoptosis and autophagy. In conclusion, epalrestat heightens sorafenib's anti-cancer effects via blocking the mTOR pathway, thus inducing cell cycle arrest, apoptosis, and autophagy.