Dihydroartemisinin is potential therapeutics for treating late-stage CRC by targeting the elevated c-Myc level

Dihydroartemisinin inhibits the development of colorectal cancer by GSK-3β/TCF7/MMP9 pathway and synergies with capecitabine

Patients with colorectal cancer (CRC) suffer from poor prognosis and lack effective drugs. Dihydroartemisinin (DHA) has anti-cancer potential but the mechanism remains unclear. We elucidated the effects and mechanism of DHA on CRC development with the aim of providing an effective, low-toxicity drug and a novel strategy for CRC. Herein, proliferation assay, transwell assay, tube formation assay, metastasis models, PDX model and AOM/DSS model were used to reveal the effects of DHA on CRC. The key pathway and target were identified by RNA-seq, ChIP, molecular docking, pull down and dual-luciferase reporter assays. As a result, DHA showed a strong inhibitory effect on the growth, metastasis and angiogenesis of CRC with no obvious toxicity, and the inhibitory effect was similar to that of the clinical drug Capecitabine (Cap). Indeed, DHA directly targeted GSK-3β to inhibit CRC development through the GSK-3β/TCF7/MMP9 pathway. Meaningfully, DHA in combination with Cap enhanced the anti-cancer effect, and alleviated Cap-induced diarrhoea, immunosuppression and inflammation. In conclusion, DHA has the potential to be an effective and low-toxicity drug for the treatment of CRC. Furthermore, DHA in combination with Cap could be a novel therapeutic strategy for CRC with improved efficacy and reduced side effects.

Lessons learned from the discovery and development of the sesquiterpene lactones in cancer therapy and prevention

INTRODUCTION

Sesquiterpene lactones (SLs) are one of the most diverse bioactive secondary metabolites found in plants and exhibit a broad range of therapeutic properties . SLs have been showing promising potential in cancer clinical trials, and the molecular mechanisms underlying their anticancer potential are being uncovered. Recent evidence also points to a potential utility of SLs in cancer prevention.

AREAS COVERED

This work evaluates SLs with promising anticancer potential based on cell, animal, and clinical models: Artemisinin, micheliolide, thapsigargin dehydrocostuslactone, arglabin, parthenolide, costunolide, deoxyelephantopin, alantolactone, isoalantolactone, atractylenolide 1, and xanthatin as well as their synthetic derivatives. We highlight actionable molecular targets and biological mechanisms underlying the anticancer therapeutic properties of SLs. This is complemented by a unique assessment of SL mechanisms of action that can be exploited in cancer prevention. We also provide insights into structure-activity and pharmacokinetic properties of SLs and their potential use in combination therapies.

EXPERT OPINION

We extract seven major lessons learned and present evidence-based solutions that can circumvent some scientific limitations or logistic impediments in SL anticancer research. SLs continue to be at the forefront of cancer drug discovery and are worth a joint interdisciplinary effort in order to leverage their potential in cancer therapy and prevention.

Effects of glycolysis and polyamine predation on intestinal epithelial barrier in colorectal cancer

Colorectal cancer (CRC) is the second most lethal cancer and the third most common cancer in the world, and its prognosis is severely affected by high intestinal mucosal permeability and increasing tumor burden. Studies have shown that the expression of hypoxia induce factor 1α (HIF1α) is up-regulated in a variety of tumor tissues, which is related to multiple metabolic reprogramming of tumor cells. However, the role of HIF1α in CRC tumor growth, tumor polyamine metabolism and intestinal mucosal barrier damage has not been studied. Here, we constructed different types of CRC tumor-bearing mice models by inoculating HCT116 cells with different levels of HIF1α expression (knockdown, wild type, overexpression) in the armpits of mice to explore the upstream and downstream regulators of HIF1α, the effects of HIF1α on the growth of CRC, and the CRC polyamine metabolism and its effect on the intestinal mucosal barrier. We found that with the increase of HIF1 gene expression, tumor growth was promoted and intestinal mucosal permeability was increased. The expression of glycolysis-related proteins was up-regulated, the rate-limiting enzyme ODC of polyamine synthesis was decreased, and the transfer protein of polyamine was increased. HPLC showed that the polyamine content in the tumor tissue of the overexpression group HIF1α OE was higher than that of the wild group HIF1α (+/+), and higher than that of the knockdown group HIF1α (-/-), but the content of polyamines in intestinal mucosa was the opposite. After supplementation of exogenous polyamines, the content of polyamines in intestinal mucosa and tumor tissue increased, and the damage of intestinal mucosa was alleviated. In conclusion, upon activation of the MYC/HIF1 pathway, tumor glycolysis is enhanced, tumors require more energy and endogenous polyamine synthesis is reduced. Therefore, in order to meet its growth needs, tumor will rob polyamines in the intestinal mucosa, resulting in intestinal mucosal epithelial barrier dysfunction.