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The transformation of normal colonic epithelium to colorectal cancer (CRC) involves a relatively ordered progression, and understanding the molecular alterations involved may aid rational design of strategies aimed at preventing or counteracting disease. Homeobox A9 (HOXA9) is an oncogene in leukemia and has been implicated in CRC pathology, although its role in disease etiology remains obscure at best. We observe that HOXA9 expression is increased in colonic adenomas compared with location-matched healthy colon epithelium. Its forced expression results in dramatic genetic and signaling changes, with increased expression of growth factors IGF1 and FLT3 , super-activity of the AKT survival pathway and a concomitant increase in compartment size. Furthermore, a reduced mRNA expression of the epithelial to mesenchymal transition marker N-cadherin as well as reduced activity of the actin cytoskeletal mediator PAK was seen, which is in apparent agreement with an observed reduced migratory response in HOXA9- overexpressing cells. Thus, HOXA9 appears closely linked with adenoma growth while impairing migration and metastasis and hence is both a marker and driver of premalignant polyp growth. Colonic polyps grow but remain premalignant for up to decades. Here, we show that HOXA9 drives growth in premalignant polyps, but simultaneously prevents further transformation. [ABSTRACT FROM AUTHOR]

Developing selectively targeted and heat-responsive nanocarriersholds paramount promises in chemotherapy. We show that this can beachieved by designing liposomes combining cationic charged and thermosensitivelipids in the bilayer. We demonstrated, using flow cytometry, livecell imaging, and intravital optical imaging, that cationic thermosensitiveliposomes specifically target angiogenic endothelial and tumor cells.Application of mild hyperthermia led to a rapid content release extra-and intracellularly in two crucial cell types in a solid tumor. [ABSTRACT FROM AUTHOR]

For amphiphilic anticancer drugs, such as the anthracyclin doxorubicin (Dox), uptake by tumor cells involves slow diffusion across the plasma membrane, a limiting factor in clinical oncology. Previously, we discovered that preinsertion of short-chain sphingolipids such as N-octanoyl-glucosylceramide (GC) in the tumor cell membrane enhances cellular Dox uptake. In the present study, we apply this strategy in vitro and in vivo by coadministering GC and Dox in a lipid nanovesicle (LNV). GC enrichment of Dox-LNVs strongly enhanced in vitro cyto-toxicity toward B16 melanoma and A431 carcinoma, as evidenced by 6-fold decreased IC50 values compared with Dox-LNVs. This correlated with enhanced cellular Dox uptake observed by confocal microscopy. Intravital optical imaging in window chamber-bearing mice with orthotopically implanted B16 melanoma demonstrated enhanced GC-mediated Dox delivery to tumor cells. Treatment of nude mice bearing human A431 xenografts with 6 mg/kg GC-Dox-LNVs almost doubled the tumor growth delay compared with Dox-LNVs. A second administration of 5 mg/kg after 3 d induced even 3-fold delay in tumor growth, while no systemic toxicity was found. GC-enriched Dox-LNVs displayed superior in vitro and in vivo antitumor activity, without systemic toxicity. This new drug delivery concept, aiming at increased membrane permeability for amphiphilic drugs, provides an opportunity to improve cancer chemotherapy. [ABSTRACT FROM AUTHOR]

Background: Creatine Kinases (CK) catalyze the reversible transfer of high-energy phosphate groups between ATP and phosphocreatine, thereby playing a storage and distribution role in cellular energetics. Brain-type CK (CK-B) deficiency is coupled to loss of function in neural cell circuits, altered bone-remodeling by osteoclasts and complement-mediated phagocytotic activity of macrophages, processes sharing dependency on actomyosin dynamics. Methodology/Principal Findings: Here, we provide evidence for direct coupling between CK-B and actomyosin activities in cortical microdomains of astrocytes and fibroblasts during spreading and migration. CK-B transiently accumulates in membrane ruffles and ablation of CK-B activity affects spreading and migration performance. Complementation experiments in CK-B-deficient fibroblasts, using new strategies to force protein relocalization from cytosol to cortical sites at membranes, confirmed the contribution of compartmentalized CK-B to cell morphogenetic dynamics. Conclusion/Significance: Our results provide evidence that local cytoskeletal dynamics during cell motility is coupled to onsite availability of ATP generated by CK-B. [ABSTRACT FROM AUTHOR]

An abstract of the article "Short-chain sphingolipids for enhanced cellular uptake of liposome-encapsulated amphiphilic anti-cancer drugs," by Albert van Hell, Wim van Blitterswijk, and Ann LB Seynhaeve is presented.

Targeting microtubules (MTs), dynamic and stable proteins in cells, by different ligands have been reported to be a potential strategy to combat cancer cells. Inorganic nanoparticles (NPs) have been widely used as anticancer, antibacterial and free radical scavenging agents, where they come in contact with biological macromolecules. The interaction between the NPs and biological macromolecules like MTs frequently occurs through different mechanisms. A prerequisite for a detailed exploration of MT structures and functions for biomedical applications like cancer therapy is to investigate profoundly the mechanisms involved in MT-NP interactions, for which the full explanation and characterization of the parameters that are responsible for the formation of a NP-protein complex are crucial. Therefore, in view of the fact that the goal of the rational NP-based future drug design and new therapies is to rely on the information of the structural details and protein-NPs binding mechanisms to manipulate the process of developing new potential drugs, a comprehensive investigation of the essence of the molecular recognition/interaction is also of considerable importance. In the present review, first, the microtubule (MT) structure and its binding sites upon interaction with MT stabilizing agents (MSAs) and MT destabilizing agents (MDAs) are introduced and rationalized. Next, MT targeting in cancer therapy and interaction of NPs with MTs are discussed. Furthermore, interaction of NPs with proteins and the manipulation of protein corona (PC), experimental techniques and direct interaction of NPs with MTs, are discussed, and finally the challenges and future perspective of the field are introduced. We envision this review can provide useful information on the manipulation of the MT lattice for the progress of cancer nanomedicine., (Copyright © 2022. Published by Elsevier B.V.)

Targeted photodynamic therapy (PDT) has the potential to selectively damage tumor tissue and to increase tumor vessel permeability. Here we characterize the tissue biodistribution of two EGFR-targeted nanobody-photosensitizer conjugates (NB-PS), the monovalent 7D12-PS and the biparatopic 7D12-9G8-PS. In addition, we report on the local and acute phototoxic effects triggered by illumination of these NB-PS which have previously shown to lead to extensive tumor damage. Methods: Intravital microscopy and the skin-fold chamber model, containing OSC-19-luc2-cGFP tumors, were used to investigate: a) the fluorescence kinetics and distribution, b) the vascular response and c) the induction of necrosis after illumination at 1 or 24 h post administration of 7D12-PS and 7D12-9G8-PS. In addition, dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) of a solid tumor model was used to investigate the microvascular status 2 h after 7D12-PS mediated PDT. Results: Image analysis showed significant tumor colocalization for both NB-PS which was higher for 7D12-9G8-PS. Intravital imaging showed clear tumor cell membrane localization 1 and 2 h after administration of 7D12-9G8-PS, and fluorescence in or close to endothelial cells in normal tissue for both NB-PS. PDT lead to vasoconstriction and leakage of tumor and normal tissue vessels in the skin-fold chamber model. DCE-MRI confirmed the reduction of tumor perfusion after 7D12-PS mediated PDT. PDT induced extensive tumor necrosis and moderate normal tissue damage, which was similar for both NB-PS conjugates. This was significantly reduced when illumination was performed at 24 h compared to 1 h after administration. Discussion: Although differences were observed in distribution of the two NB-PS conjugates, both led to similar necrosis. Clearly, the response to PDT using NB-PS conjugates is the result of a complex mixture of tumor cell responses and vascular effects, which is likely to be necessary for a maximally effective treatment., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

ATP is the "principal energy currency" in metabolism and the most versatile small molecular regulator of cellular activities. Although already much is known about the role of ATP in fundamental processes of living systems, data about its compartmentalization are rather scarce, and we still have only very limited understanding of whether patterns in the distribution of intracellular ATP concentration ("ATP inhomogeneity") do exist and have a regulatory role. Here we report on the analysis of coupling of local ATP supply to regulation of actomyosin behavior, a widespread and dynamic process with conspicuous high ATP dependence, which is central to cell shape changes and cell motility. As an experimental model, we use embryonic fibroblasts from knock-out mice without major ATP-ADP exchange enzymes, in which we (re)introduce the ATP/ADP exchange enzyme adenylate kinase-1 (AK1) and deliberately manipulate its spatial positioning by coupling to different artificial location tags. By transfection-complementation of AK1 variants and comparison with yellow fluorescent protein controls, we found that motility and spreading were enhanced in cells with AK1 with a focal contact guidance tag. Intermediary enhancement was observed in cells with membrane-targeted or cytosolic AK1. Use of a heterodimer-inducing approach for transient translocation of AK1 to focal contacts under conditions of constant global AK1 activity in the cell corroborated these results. Based on our findings with these model systems, we propose that local ATP supply in the cell periphery and "on site" fuelling of the actomyosin machinery, when maintained via enzymes involved in phosphoryl transfer, are codetermining factors in the control of cell motility.

Tumour necrosis factor-alpha (TNF) has been used in the clinic for more than 10 years in an isolated limb perfusion (ILP). However, intra-tumoural expression of TNF receptor-1 (TNF-R1) and TNF-R1 upregulating factors are unknown. We determined the expression of TNF-R1, proEMAP and endothelial monocyte-activating polypeptide-II (EMAP-II) before and after ILP and evaluated this against clinical response. Tumour biopsies were taken before and after ILP of patients (n = 27) with advanced sarcoma or metastatic melanoma. Biopsies were randomly analysed by western blotting for proEMAP/EMAP-II and TNF-R1 expression. Appropriate melanoma biopsies were stained for EMAP-II, TNF-R1, CD31 and CD68. For melanomas we found that an up-regulation of EMAP-II, in contrast to proEMAP or TNF-R1, directly after ILP significantly correlated with a complete tumour response. No correlation was found for sarcoma patients. In a comparative analysis we found that the overall proEMAP and EMAP-II expression was higher in melanoma as compared to sarcoma cases and measurements in cell lines revealed high proEMAP expression by melanoma cells. We report high EMAP-II expression by endothelial cells and association with macrophages. In addition, macrophages are recruited to vessel-remnants after ILP. An upregulation of EMAP-II directly after ILP of melanoma patients correlates with and might predict a complete response to TNF-based ILP. The association of macrophages with EMAP-II expression and vascular damage suggests a role for EMAP-II in regulating the TNF-based anti-tumour effects observed with an ILP. Analysis of EMAP-II expression in melanoma biopsies should be implemented in the ILP procedure.

To study tumor therapeutic treatment modalities, whether from a clinical, preclinical, or fundamental point of view, the use of clinically relevant animal models is indispensable. Particularly when the treatment comprises a multitargeted approach, (e.g., both tumor cells and endothelial cells are targeted), the in vitro data will be of very limited value. Well-chosen animal models will provide conclusive data on the activity of the drug in the complex in vivo setting. Moreover, when the treatment targets the stromal compartment of the tumor rather than the tumor cells directly, insight into the mechanism of action is only possible when studied in vivo. This approach is of great importance for studies on the use of tumor necrosis factor-alpha (TNFalpha) in solid tumor therapy. Although TNFalpha has shown activity toward tumor cells in vitro directly, we and others have demonstrated that an important activity of this cytokine is directed toward the tumor vasculature. To elucidate the working mechanism of TNFalpha and to test possible treatment modalities, the animal models described here are crucial. In this chapter we will describe the use of specific animal models for efficacy studies, such as isolated limb perfusion and isolated liver perfusion in the rat.