Trabectedin modulates macrophage polarization in the tumor-microenvironment. Role of KV1.3 and KV1.5 channels

PCL-PEtOx-based Crystalline-core Micelles for the Targeted Delivery of Paclitaxel and Trabectedin in Ovarian Cancer Therapy

Ovarian cancer (OC), which primarily metastasizes through ascites, is both invasive and fatal. Despite its toxicity and drug resistance, the platinum-based chemotherapy Taxol®+Carboplatin has been the first-line standard treatment for decades. Trabectedin (TBD) is a recently developed, highly effective antitumor drug that is also capable of regulating tumor-associated macrophages (TAMs), however, its severe side-effects hinder further clinical application. Here, we developed safe and efficient pH-responsive crystalline-core micelles for the combined treatment of OCs, exploiting parallel delivery of paclitaxel (PTX) and TBD. PCL-PEtOx-COOH was selected as the optimal carrier to encapsulate PTX or TBD, which self-assemble into micelles with internal crystalline cores. The carboxyl group exposed on the surface of the micelles was utilized to react with the amines of Herceptin and hyaluronic acid cross-linked polymer (Herceptin-HA) to form PTX(Target). Similarly, TBD(Target) was formed by reaction with the CD206-targeted peptide mUNO. The low critical micelle concentrations of PTX(Target) and TBD(Target) stabilize the micelles in the bloodstream and normal tissues to prevent drug release. In an acidic microenvironment, the tertiary amide group on PEtOx chain of micelles ionizes, causing disassembly and pH-responsive release. Compared with Taxol®+Carboplatin, the combination therapy displayed dramatically improved safety and efficacy, as evidenced by the elimination of peritoneal tumor spheroids and reduced expression of NOX4, a gene that is overexpressed in most OC tissues. Furthermore, in human tissues, the ROS-response gene NOX4 is linked to the development of M2-type TAMs. Collectively, this study provides a safe and effective non-platinum-based chemotherapy for OC, offering an alternative to traditional Taxol®+Carboplatin. STATEMENT OF SIGNIFICANCE: (1) Significance: This work reports a new approach for ovarian cancer (OC) treatment. We utilized trabectedin (TBD) which a recently developed, highly effective antitumor drug that is also capable of regulating tumor associated macrophages (TAMs) combined with paclitaxel (PTX) to replace platinum-based chemotherapy Taxol®+Carboplatin (TC regimen). Compared to the clinical formulations, Yondelis® and Taxol®, pH-responsive PCL-PEtOx-based crystalline-core micelles were utilized for targeted independent delivery of TBD and PTX to TAMs and tumor cells, which maintained safe and efficient transport, overcoming the challenges posed by TAMs and carboplatin resistance. The system capabilities have also been confirmed in organoid and PDX models. (2) This is the first report demonstrating that this approach simultaneously overcomes the abdominal metastasis and carboplatin resistance of OC.

RvD1 and LXA4 inhibitory effects on cardiac voltage-gated potassium channels

The resolution of inflammation is modulated by specialized pro-resolving lipid mediators (SPMs), which can be modified in some cardiovascular diseases. Among these SPMs, RvD1 and LXA4 prevent atrial fibrillation (AF) remodeling and cardiac hypertrophy, respectively in animal models. However, little is known about their electrophysiological effects on cardiac voltage-gated (VG) ion channels. We used the patch-clamp technique in heterologous systems and cardiomyocytes to assess the acute effects of RvD1, and LXA4, on VG potassium currents. In silico simulations were used to predict the effect of current modulation on the atrial and ventricular action potentials (AP). RvD1 (5 nM) reduced IKs (channel KV7.1/KCNE1) in COS-7 cells and guinea-pig cardiomyocytes by 50.3 ± 7.3 % and 29.9 ± 5.4 % at + 40 mV, respectively, without modifying its voltage dependence. RvD1 was more potent than LXA4. In heterologous systems, RvD1 was also tested on IKur (channel KV1.5), Ito (channel KV4.3/KChIP2), IKr (channel KV11.1), and IK1 (channel Kir2.1) with the largest inhibitory effect on IKs and IKr. In in silico simulations RvD1 prolonged repolarization significantly in both atrial and ventricular myocytes. All these results provide a comprehensive evaluation of RvD1 and LXA4 on cardiac human potassium channels, at pathophysiologically relevant concentrations, being RvD1 more potent than LXA4. The predicted effects on the AP suggest that, along with their antiinflammatory action, RvD1 may reverse AF-induced electrical remodeling in the atria by their modulation of K+ currents. The same action might instead contribute to ventricular functional remodeling; however, direct evidence for this is missing.

Ion channels in macrophages: Implications for disease progression

RATIONALE

Macrophages are immune cells found throughout the body and exhibit morphological and functional diversity. Macrophages have been implicated in a wide range of diseases, including autoimmune diseases, acute liver injury, cardiovascular diseases, lung diseases and tumours. Ion channels are transmembrane glycoproteins with important functions in maintaining homeostasis in the intra- and extracellular environment and mediating signal transduction. Many studies have shown that different types of ion channels influence the role of macrophages in the development of various diseases. In recent years, studies on the role of ion channels in macrophages in immune regulation and inflammatory responses have attracted much attention.

OBJECTIVE AND FINDINGS

In order to gain a deeper understanding of the role of macrophage ion channels, this paper reviews the recent research progress on the role of macrophage ion channels in recent years. The aim is to explore the role of different ion channels in the regulation of macrophage function and their impact on a variety of disease processes. The most studied channels are calcium, sodium and potassium channels, most of which are located in the cell membrane. Among these, TRP channels have a more complex role in M1 and M2 macrophage types.

CONCLUSION

Ion channels are critical for the functional regulation of macrophages. Targeting ion channels provides new avenues for disease prevention and treatment. This review provides researchers with new ideas and introduces readers to the current state of research on ion channels in macrophages.

HMGA1 regulates trabectedin sensitivity in advanced soft-tissue sarcoma (STS): A Spanish Group for Research on Sarcomas (GEIS) study

HMGA1 is a structural epigenetic chromatin factor that has been associated with tumor progression and drug resistance. Here, we reported the prognostic/predictive value of HMGA1 for trabectedin in advanced soft-tissue sarcoma (STS) and the effect of inhibiting HMGA1 or the mTOR downstream pathway in trabectedin activity. The prognostic/predictive value of HMGA1 expression was assessed in a cohort of 301 STS patients at mRNA (n = 133) and protein level (n = 272), by HTG EdgeSeq transcriptomics and immunohistochemistry, respectively. The effect of HMGA1 silencing on trabectedin activity and gene expression profiling was measured in leiomyosarcoma cells. The effect of combining mTOR inhibitors with trabectedin was assessed on cell viability in vitro studies, whereas in vivo studies tested the activity of this combination. HMGA1 mRNA and protein expression were significantly associated with worse progression-free survival of trabectedin and worse overall survival in STS. HMGA1 silencing sensitized leiomyosarcoma cells for trabectedin treatment, reducing the spheroid area and increasing cell death. The downregulation of HGMA1 significantly decreased the enrichment of some specific gene sets, including the PI3K/AKT/mTOR pathway. The inhibition of mTOR, sensitized leiomyosarcoma cultures for trabectedin treatment, increasing cell death. In in vivo studies, the combination of rapamycin with trabectedin downregulated HMGA1 expression and stabilized tumor growth of 3-methylcholantrene-induced sarcoma-like models. HMGA1 is an adverse prognostic factor for trabectedin treatment in advanced STS. HMGA1 silencing increases trabectedin efficacy, in part by modulating the mTOR signaling pathway. Trabectedin plus mTOR inhibitors are active in preclinical models of sarcoma, downregulating HMGA1 expression levels and stabilizing tumor growth.

Trabectedin and Lurbinectedin Modulate the Interplay between Cells in the Tumour Microenvironment-Progresses in Their Use in Combined Cancer Therapy

Trabectedin (TRB) and Lurbinectedin (LUR) are alkaloid compounds originally isolated from Ecteinascidia turbinata with proven antitumoral activity. Both molecules are structural analogues that differ on the tetrahydroisoquinoline moiety of the C subunit in TRB, which is replaced by a tetrahydro-β-carboline in LUR. TRB is indicated for patients with relapsed ovarian cancer in combination with pegylated liposomal doxorubicin, as well as for advanced soft tissue sarcoma in adults in monotherapy. LUR was approved by the FDA in 2020 to treat metastatic small cell lung cancer. Herein, we systematically summarise the origin and structure of TRB and LUR, as well as the molecular mechanisms that they trigger to induce cell death in tumoral cells and supporting stroma cells of the tumoral microenvironment, and how these compounds regulate immune cell function and fate. Finally, the novel therapeutic venues that are currently under exploration, in combination with a plethora of different immunotherapeutic strategies or specific molecular-targeted inhibitors, are reviewed, with particular emphasis on the usage of immune checkpoint inhibitors, or other bioactive molecules that have shown synergistic effects in terms of tumour regression and ablation. These approaches intend to tackle the complexity of managing cancer patients in the context of precision medicine and the application of tailor-made strategies aiming at the reduction of undesired side effects.