Dexmedetomidine disrupts esophagus cancer tumorigenesis by modulating circ_0003340/miR-198/HMGA2 axis

CircRNAs as upstream regulators of miRNA//HMGA2 axis in human cancer

High mobility group protein A2 (HMGA2) is widely recognized as a chromatin-binding protein, whose overexpression is observed in nearly all human cancers. It exerts its oncogenic effects by influencing various cellular processes such as the epithelial-mesenchymal transition, cell differentiation, and DNA damage repair. MicroRNA (miRNA) serves as a pivotal gene expression regulator, concurrently modulating multiple genes implicated in cancer progression, including HMGA2. It also serves as a significant biomarker for cancer. Circular RNA (circRNA) plays a crucial role in gene regulation primarily by sequestering miRNAs and impeding their ability to enhance the expression of other genes, including HMGA2. Increasingly, studies have underscored the vital role of miRNA/HMGA2 interactions in cancer. Given the significance of circRNA as an upstream regulatory mediator and the complexity of regulatory mechanisms, we hereby present a comprehensive overview of the pivotal role of circRNAs as upstream regulators of the miRNA//HMGA2 axis in human cancers. This insight may herald a novel direction for future cancer research.

Dexmedetomidine hydrochloride plus sufentanil citrate inhibits glucose metabolism and epithelial‑mesenchymal transition in human esophageal squamous carcinoma KYSE30 cells by modulating the JAK/STAT3/HIF‑1α axis

Dexmedetomidine hydrochloride (DEX-HCl) and sufentanil citrate (SFC) are commonly used anesthetic drugs for esophageal cancer (EC) surgery. The present study was performed to investigate the effect of DEX-HCl and SFC treatment on glucose metabolism and epithelial-mesenchymal transition in EC. Cell counting kit-8 (CCK8), clonogenic, wound healing and Transwell migration assays were performed to assess the effects of the DEX-HCl and SFC on KYSE30 cell proliferation, invasion and migration. Changes in lactate and glucose levels in KYSE30 cells were also detected. Western blot analysis was used to determine the protein expression levels of the JAK/STAT signaling pathway and glucose metabolism-related proteins. The results of CCK8, clonogenic and wound healing assays demonstrated that DEX-HCl and SFC inhibited KYSE30 cell proliferation, invasion and migration. Similarly, the combined DEX-HCl and SFC treatment significantly reduced lactate production, ATP production and glucose levels in KYSE30 cells. Western blotting indicated that DEX-HCl and SFC could reduce JAK/STAT and metastasis-related protein expression. Demonstrating a reduction in Hexokinase 2, matrix metallopeptidase 2 and 9, N-cadherin and lactate dehydrogenase A protein expression levels. The effects of DEX-HCl and SFC combined treatment were counteracted by the addition of JAK/STAT pathway activator RO8191, which suggested that DEX-HCl and SFC could serve a role in mediating the JAK/STAT signaling pathway in KYSE30 cells.

Trial watch: dexmedetomidine in cancer therapy

Dexmedetomidine (DEX) is a highly selective α2-adrenoceptor agonist that is widely used in intensive and anesthetic care for its sedative and anxiolytic properties. DEX has the capacity to alleviate inflammatory pain while limiting immunosuppressive glucocorticoid stress during major surgery, thus harboring therapeutic benefits for oncological procedures. Recently, the molecular mechanisms of DEX-mediated anticancer effects have been partially deciphered. Together with additional preclinical data, these mechanistic insights support the hypothesis that DEX-induced therapeutic benefits are mediated via the stimulation of adaptive anti-tumor immune responses. Similarly, published clinical trials including ancillary studies described an immunostimulatory role of DEX during the perioperative period of cancer surgery. The impact of DEX on long-term patient survival remains elusive. Nevertheless, DEX-mediated immunostimulation offers an interesting therapeutic option for onco-anesthesia. Our present review comprehensively summarizes data from preclinical and clinical studies as well as from ongoing trials with a distinct focus on the role of DEX in overcoming (tumor microenvironment (TME)-imposed) cancer therapy resistance. The objective of this update is to guide clinicians in their choice toward immunostimulatory onco-anesthetic agents that have the capacity to improve disease outcome.

HMGA2 regulation by miRNAs in cancer: affecting cancer hallmarks and therapy response

High mobility group A 2 (HMGA2) is a protein that modulates the structure of chromatin in the nucleus. Importantly, aberrant expression of HMGA2 occurs during carcinogenesis, and this protein is an upstream mediator of cancer hallmarks including evasion of apoptosis, proliferation, invasion, metastasis, and therapy resistance. HMGA2 targets critical signaling pathways such as Wnt/β-catenin and mTOR in cancer cells. Therefore, suppression of HMGA2 function notably decreases cancer progression and improves outcome in patients. As HMGA2 is mainly oncogenic, targeting expression by non-coding RNAs (ncRNAs) is crucial to take into consideration since it affects HMGA2 function. MicroRNAs (miRNAs) belong to ncRNAs and are master regulators of vital cell processes, which affect all aspects of cancer hallmarks. Long ncRNAs (lncRNAs) and circular RNAs (circRNAs), other members of ncRNAs, are upstream mediators of miRNAs. The current review intends to discuss the importance of the miRNA/HMGA2 axis in modulation of various types of cancer, and mentions lncRNAs and circRNAs, which regulate this axis as upstream mediators. Finally, we discuss the effect of miRNAs and HMGA2 interactions on the response of cancer cells to therapy. Regarding the critical role of HMGA2 in regulation of critical signaling pathways in cancer cells, and considering the confirmed interaction between HMGA2 and one of the master regulators of cancer, miRNAs, targeting miRNA/HMGA2 axis in cancer therapy is promising and this could be the subject of future clinical trial experiments.

Dexamethasone as an anti-cancer or hepatotoxic

The linkage between inflammation and oxidative stress in liver damage has been proven and is undeniable; dexamethasone with some antioxidants can reduce the toxicity of liver tissue. Due to the importance of cancer treatment, glucocorticoids' synergistic effect in inhibiting cancer cell growth is also investigated. Dexamethasone alone and combined with etoposide were tested at concentrations of 1, 5, and 10 μM to evaluate the potency of dexamethasone in inhibiting the growth of A549 cells using oxidative stress factors and DNA damage. Also, intraperitoneal injection of dexamethasone in rats was used to induce liver toxicity. Coenzyme Q10 at different concentrations (1, 10, and 50 mg/kg) was used as an antioxidant to assess the oxidative stress factors and measure Caspase-3 activity. The results showed that dexamethasone combined with etoposide could significantly inhibit the growth of cancer cells and induce apoptosis. Treatment of A549 cells using dexamethasone also inhibits cancer cells' growth by inducing oxidative stress and DNA damage. Dexamethasone also, by inducing oxidative stress and activation of caspase 3, ultimately causes hepatotoxicity. Treatment with different concentrations of CoQ10 showed improved mitochondrial function, antioxidant defense, and liver enzyme. The best effect of coenzyme Q10 on dexamethasone-induced hepatotoxicity is 50 mg/kg. As a result, dexamethasone (alone and combined with etoposide) has an anti-cancer effect by damaging DNA and inducing oxidative stress. Also, CoQ10 has antioxidant effects against dexamethasone-induced hepatotoxicity by improving mitochondrial function and reducing caspase-3 activity.