Novel Non-Congeneric Derivatives of the Choline Kinase Alpha Inhibitor ICL-CCIC-0019

Choline kinases: Enzymatic activity, involvement in cancer and other diseases, inhibitors

One of the aspects of tumor metabolism that distinguish it from healthy tissue is the phosphorylation of choline by choline kinases, which initiates the synthesis of phosphatidylcholine. Presently, there is a lack of comprehensive reviews discussing the current understanding of the role of choline kinase in cancer processes, as well as studies on the anti-tumor properties of choline kinase inhibitors. To address these gaps, this review delves into the enzymatic and non-enzymatic properties of CHKα and CHKβ and explores their precise involvement in cancer processes, particularly cancer cell proliferation. Additionally, we discuss clinical aspects of choline kinases in various tumor types, including pancreatic ductal adenocarcinoma, ovarian cancer, lung adenocarcinoma, lymphoma, leukemia, hepatocellular carcinoma, colon adenocarcinoma, and breast cancer. We examine the potential of CHKα inhibitors as anti-tumor drugs, although they are not yet in the clinical trial phase. Finally, the paper also touches upon the significance of choline kinases in non-cancerous diseases.

Nasal Administration of a Nanoemulsion Based on Methyl Ferulate and Eugenol Encapsulated in Chitosan Oleate: Uptake Studies in the Central Nervous System

Background/Objectives: The phytochemicals ferulic acid (Fer) and eugenol display neuroprotective effects for their anti-oxidative properties; moreover, eugenol can induce dopamine (DA) release from dopaminergic neuronal cells. However, poor bioavailability and/or fast elimination rate limit their clinical benefits. We therefore propose a new nasal formulation based on a nanoemulsion (NE) for the jointed brain-targeting of eugenol and methyl ferulate (Fer-Me, i.e., a Fer-lipidized derivative maintaining the parent compound anti-oxidative properties). NE was obtained using chitosan oleate, a surfactant combining mucoadhesive and absorption-enhancing properties with stabilizing effects on the dispersion of eugenol, used as a Fer-Me vehicle. Methods: The nasal formulation was obtained by spontaneous emulsification processes; cell viability and uptake studies were performed on an in vitro model of respiratory mucosa (RPMI 2650 cells). After intravenous and nasal administrations, the pharmacokinetic profiles of eugenol and Fer-Me in rats' bloodstreams and cerebrospinal fluid (CSF) were analyzed via HPLC-UV analysis. Results: The NE dispersed-phase mean diameter was 249.22 ± 32.78 nm; Fer-Me and eugenol loading in NE was about 1 and 2 mg/mL, respectively. NE increased the uptake of loaded compounds by mucosal cells. Following intravenous administration, the Fer-Me plasma half-life was 10.08 ± 0.37 min, and a negligible ability of the compound to permeate in the CSF, compared to eugenol, was observed. NE nasal administration allowed us to sensibly increase the Fer-Me brain-targeting and prolong the eugenol permanence in the CSF. Conclusions: This nasal formulation appears promising to overcome Fer and eugenol pharmacokinetic issues. The possible translational relevance of the present findings is discussed.

Targeted inhibition of CHKα and mTOR in models of pancreatic ductal adenocarcinoma: A novel regimen for metastasis

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic malignancy for which there are currently no effective anti-metastatic therapies. Herein, we employed single-cell RNA sequencing and metabolomics analysis to demonstrate that metastatic cells highly express focal adhesion kinase (FAK), which promotes metastasis by remodeling choline kinase α (CHKα)-dependent choline metabolism. We designed a novel CHKα inhibitor, CHKI-03, and verified its efficacy in inhibiting metastasis in multiple preclinical models. Classical and newly synthesized small-molecule inhibitors have previously been used to assess the therapeutic potential of targeting mTOR and CHKα in various animal models. Mechanistically, FAK activated mTOR and its downstream HIF-1α, thereby elevating CHKα expression and promoting the proliferation, migration, and invasion of PDAC cells, as well as tumor growth and metastasis. Consistently, high expression levels of both FAK and CHKα are correlated with poor prognosis in patients with PDAC. Notably, CHK1-03 inhibited CHKα expression and also suppressed mTORC1 phosphorylation, disrupting the mTORC1-CHKα positive feedback loop. In addition, the combination of CHKI-03 and the mTORC1 inhibitor rapamycin synergistically inhibited tumor growth and metastasis in PDX models. The combination of CHKI-03 and rapamycin demonstrates considerable therapeutic efficacy in PDO models resistant to gemcitabine. Our findings reveal a pivotal mechanism underlying PDAC metastasis regulated by mTORC1-CHKα loop-dependent choline metabolism reprogramming, highlighting the therapeutic potential of this novel regimen for treating PDAC metastasis.

MALAT1 as a Regulator of the Androgen-Dependent Choline Kinase A Gene in the Metabolic Rewiring of Prostate Cancer

Simple Summary

Despite the rapid advance in cancer therapies, treatment-resistant relapse remains a significant challenge in cancer treatment. Acquired resistance arises during or after treatment administration, and is usually the main contributor to relapse. For example, prostate cancer, the most frequent type of cancer in the elderly male population, frequently develops into aggressive forms resistant to chemical and hormonal therapies. In this condition, the so-called “cholinic phenotype” that is characterized by the overexpression of choline kinase alpha (CHKA) and increased phosphocholine levels leads to aberrant lipid metabolism. Our work demonstrates that CHKA, which is necessary for membrane phospholipid synthesis, is a target of the long non-coding RNA MALAT1. This study helps to further decipher how MALAT1 affects the regulation of crucial phospholipid/sphingolipid metabolic enzymes, as well as how the androgen receptor pathway is involved in MALAT1-dependent transcriptional regulation.

Abstract

Background. Choline kinase alpha (CHKA), an essential gene in phospholipid metabolism, is among the modulated MALAT1-targeted transcripts in advanced and metastatic prostate cancer (PCa). Methods. We analyzed CHKA mRNA by qPCR upon MALAT1 targeting in PCa cells, which is characterized by high dose-responsiveness to the androgen receptor (AR) and its variants. Metabolome analysis of MALAT1-depleted cells was performed by quantitative High-resolution 1 H-Nuclear Magnetic Resonance (NMR) spectroscopy. In addition, CHKA genomic regions were evaluated by chromatin immunoprecipitation (ChIP) in order to assess MALAT1-dependent histone-tail modifications and AR recruitment. Results. In MALAT1-depleted cells, the decrease of CHKA gene expression was associated with reduced total choline-containing metabolites compared to controls, particularly phosphocholine (PCho). Upon MALAT1 targeting a significant increase in repressive histone modifications was observed at the CHKA intron-2, encompassing relevant AR binding sites. Combining of MALAT1 targeting with androgen treatment prevented MALAT1-dependent CHKA silencing in androgen-responsive (LNCaP) cells, while it did not in hormone-refractory cells (22RV1 cells). Moreover, AR nuclear translocation and its activation were detected by confocal microscopy analysis and ChIP upon MALAT1 targeting or androgen treatment. Conclusions. These findings support the role of MALAT1 as a CHKA activator through putative association with the liganded or unliganded AR, unveiling its targeting as a therapeutic option from a metabolic rewiring perspective.