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Cholangiocarcinoma (CCA) is a type of primary liver cancer originating from the biliary tract epithelium, characterized by limited treatment options for advanced cases and low survival rates. This study aimed to establish an orthotopic mouse model for CCA and monitor tumor growth using PET/MR imaging. Murine CCA cells were implanted into the liver lobe of male C57BL/6J mice. The imaging groups included contrast-enhanced (CE) MR, CE-MR with static [18F]FDG-PET, and dynamic [18F]FDG-PET. Tumor volume and FDG uptake were measured weekly over four weeks. Early tumor formation was visible in CE-MR images, with a gradual increase in volume over time. Dynamic FDG-PET revealed an increase in the metabolic glucose rate (MRGlu) over time. Blood analysis showed pathological changes in liver-related parameters. Lung metastases were observed in nearly all animals after four weeks. The study concludes that PET-MR imaging effectively monitors tumor progression in the CCA mouse model, providing insights into CCA development and potential treatment strategies.
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Chemotherapy with irinotecan (CPT-11), the pro-drug of the highly cytotoxic SN-38, is among the standard-of-care treatments for colorectal cancer. To counteract undesired toxic side effects on healthy tissue such as the intestinal epithelium, the use of preparations rich in polyphenols with anti-oxidative and anti-inflammatory properties such as anthocyanins has been proposed. In the present study, the question of whether non-tumorigenic human epithelium cells (HCEC-1CT) can be protected against the cytotoxic impact of SN-38 by anthocyanin-rich polyphenol extracts without compromising the desired therapeutic effect against tumor cells (HCT-116) was addressed. Hence, single and combinatory effects of anthocyanin-rich polyphenol extracts of elderberry (EB), bilberry (Bil), blackberry (BB) and black currant (BC) with the chemotherapeutic drug SN-38 were investigated. Out of the extracts, BB showed the most potent concentration-dependent cytotoxicity alone and in combination with SN-38, with even stronger effects in non-tumorigenic HCEC-1CT cells. In cytotoxic concentrations, BB decreased the level of DNA/topoisomerase I covalent complexes in HCEC-1CT cells below base level but without concomitant reduction in SN-38-induced DNA strand breaks. The herein reported data argue towards an interference of anthocyanins with successful treatment of cancer cells and a lack of protective properties in healthy cells.
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Sphaeropsidins are iso-pimarane diterpenes produced by phytopathogenic fungi that display promising anticancer activities. Sphaeropsidin A, in particular, has been shown to counteract regulatory volume increase, a process used by cancer cells to avoid apoptosis. This study reports the hemi-synthesis of new lipophilic derivatives obtained by modifications of the C15,C16-alkene moiety. Several of these compounds triggered severe ER swelling associated with strong proteasomal inhibition and consequently cell death, a feature that was not observed with respect to mode of action of the natural product. Significantly, an analysis from the National Cancer Institute sixty cell line testing did not reveal any correlations between the most potent derivative and any other compound in the database, except at high concentrations (LC50). This study led to the discovery of a new set of sphaeropsidin derivatives that may be exploited as potential anti-cancer agents, notably due to their maintained activity towards multidrug resistant models.
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Retículo Endoplásmico , Humanos , Retículo Endoplásmico/efectos de los fármacos , Retículo Endoplásmico/metabolismo , Línea Celular Tumoral , Apoptosis/efectos de los fármacos , Antineoplásicos/farmacología , Antineoplásicos/química , Diterpenos/farmacología , Diterpenos/química , Abietanos/farmacología , Abietanos/químicaRESUMEN
Current standard-of-care systemic therapy options for locally advanced and metastatic bladder cancer (BC), which are predominantly based on cisplatin-gemcitabine combinations, are limited by significant treatment failure rates and frailty-based patient ineligibility. We previously addressed the urgent clinical need for better-tolerated BC therapeutic strategies using a drug screening approach, which identified outstanding antineoplastic activity of clofarabine in preclinical models of BC. To further assess clofarabine as a potential BC therapy component, we conducted head-to-head comparisons of responses to clofarabine versus gemcitabine in preclinical in vitro and in vivo models of BC, complemented by in silico analyses. In vitro data suggest a distinct correlation between the two antimetabolites, with higher cytotoxicity of gemcitabine, especially against several nonmalignant cell types, including keratinocytes and endothelial cells. Accordingly, tolerance of clofarabine (oral or intraperitoneal application) was distinctly better than for gemcitabine (intraperitoneal) in patient-derived xenograft models of BC. Clofarabine also exhibited distinctly superior anticancer efficacy, even at dosing regimens optimized for gemcitabine. Neither complete remission nor cure, both of which were observed with clofarabine, were achieved with any tolerable gemcitabine regimen. Taken together, our findings demonstrate that clofarabine has a better therapeutic window than gemcitabine, further emphasizing its potential as a candidate for drug repurposing in BC. PATIENT SUMMARY: We compared the anticancer activity of clofarabine, a drug used for treatment of leukemia but not bladder cancer, and gemcitabine, a drug currently used for chemotherapy against bladder cancer. Using cell cultures and mouse models, we found that clofarabine was better tolerated and more efficacious than gemcitabine, and even cured implanted tumors in mouse models. Our results suggest that clofarabine, alone or in combination schemes, might be superior to gemcitabine for the treatment of bladder cancer.
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PURPOSE OF REVIEW: Bladder cancer incidence is on the rise, and until recently, there has been little to no change in treatment regimens over the last 40âyears. Hence, it is imperative to work on strategies and approaches to untangle the complexity of intra- and inter-tumour heterogeneity of bladder cancer with the aim of improving patient-specific care and treatment outcomes. The focus of this review is therefore to highlight novel targets, advances, and therapy approaches for bladder cancer patients. RECENT FINDINGS: The success of combining an antibody-drug conjugate (ADC) with immunotherapy has been recently hailed as a game changer in treating bladder cancer patients. Hence, interest in other ADCs as a treatment option is also rife. Furthermore, strategies to overcome chemoresistance to standard therapy have been described recently. In addition, other studies showed that targeting genomic alterations (e.g. mutations in FGFR3 , DNA damage repair genes and loss of the Y chromosome) could also be helpful as prognostic and treatment stratification biomarkers. The use of single-cell RNA sequencing approaches has allowed better characterisation of the tumour microenvironment and subsequent identification of novel targets. Functional precision medicine could be another avenue to improve and guide personalized treatment options. SUMMARY: Several novel preclinical targets and treatment options have been described recently. The validation of these advances will lead to the development and implementation of robust personalized treatment regimens for bladder cancer patients.
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Medicina de Precisión , Neoplasias de la Vejiga Urinaria , Humanos , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/terapia , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/patología , Medicina de Precisión/métodos , Terapia Molecular Dirigida/métodos , Inmunoconjugados/uso terapéutico , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Microambiente Tumoral/efectos de los fármacos , Inmunoterapia/métodosRESUMEN
PURPOSE OF REVIEW: Bladder cancer (BC) is a highly heterogenous disease comprising tumours of various molecular subtypes and histologic variants. This heterogeneity represents a major challenge for the development of novel therapeutics. Preclinical models that closely mimic in vivo tumours and reflect their diverse biology are indispensable for the identification of therapies with specific activity in various BC subtypes. In this review, we summarize efforts and progress made in this context during the last 24âmonths. RECENT FINDINGS: In recent years, one main focus was laid on the development of patient-derived BC models. Patient-derived organoids (PDOs) and patient-derived xenografts (PDXs) were demonstrated to widely recapitulate the molecular and histopathological characteristics, as well as the drug response profiles of the corresponding tumours of origin. These models, thus, represent promising tools for drug development and personalized medicine. Besides PDXs, syngenic in vivo models are of growing importance. Since these models are generated using immunocompetent hosts, they can, amongst others, be used to develop novel immunotherapeutics and to evaluate the impact of the immune system on drug response and resistance. SUMMARY: In the past two years, various in vivo and in vitro models closely recapitulating the biology and heterogeneity of human bladder tumours were developed.
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Neoplasias de la Vejiga Urinaria , Neoplasias de la Vejiga Urinaria/terapia , Neoplasias de la Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/tratamiento farmacológico , Neoplasias de la Vejiga Urinaria/genética , Neoplasias de la Vejiga Urinaria/inmunología , Humanos , Animales , Modelos Animales de Enfermedad , Organoides , Medicina de Precisión/métodos , Ensayos Antitumor por Modelo de Xenoinjerto , Antineoplásicos/uso terapéutico , Antineoplásicos/farmacologíaRESUMEN
While platinum-based chemotherapeutic agents have established themselves as indispensable components of anticancer therapy, they are accompanied by a variety of side effects and the rapid occurrence of drug resistance. A promising strategy to address these challenges is the use of platinum(iv) prodrugs, which remain inert until they reach the tumor tissue, thereby mitigating detrimental effects on healthy cells. Typically, platinum drugs are part of combination therapy settings. Consequently, a very elegant strategy is the development of platinum(iv) prodrugs bearing a second, clinically relevant therapeutic in axial position. In the present study, we focused on gemcitabine as an approved antimetabolite, which is highly synergistic with platinum drugs. In addition, to increase plasma half-life and facilitate tumor-specific accumulation, an albumin-binding maleimide moiety was attached. Our investigations revealed that maleimide-cisplatin(iv)-gemcitabine complexes cannot carry sufficient amounts of gemcitabine to induce a significant effect in vivo. Consequently, we designed a carboplatin(iv) analog, that can be applied at much higher doses. Remarkably, this novel analog demonstrated impressive in vivo results, characterized by significant improvements in overall survival. Notably, these encouraging results could also be transferred to an in vivo xenograft model with acquired gemcitabine resistance, indicating the high potential of this approach.
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Anti-oxidant, -inflammatory, and -carcinogenic activities of bioactive plant constituents, such as anthocyanins, have been widely discussed in literature. However, the potential interaction of anthocyanin-rich extracts with routinely used chemotherapeutics is still not fully elucidated. In the present study, anthocyanin-rich polyphenol extracts of blackberry (BB), bilberry (Bil), black currant (BC), elderberry (EB), and their respective main anthocyanins (cyanidin-3-O-glucoside, delphinidin-3-O-glucoside, cyanidin-3-O-rutinoside, and cyanidin-3-O-sambubioside) were investigated concerning their cytotoxic and DNA-damaging properties in murine CT26 cells either alone or in combination with the chemotherapeutic agent SN-38. BB exerted potent cytotoxic effects, while Bil, BC, and EB only had marginal effects on cell viability. Single anthocyanins comprised of the extracts could not induce comparable effects. Even though the BB extract further pronounced SN-38-induced cytotoxicity and inhibited cell adhesion at 100-200 µg/mL, no effect on DNA damage was observed. In conclusion, anti-carcinogenic properties of the extracts on CT26 cells could be ranked BB >> BC ≥ Bil ≈ EB. Mechanisms underlying the potent cytotoxic effects are still to be elucidated since the induction of DNA damage does not play a role.
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Antocianinas , Neoplasias del Colon , Ratones , Animales , Antocianinas/farmacología , Frutas , Irinotecán , Extractos Vegetales/farmacología , Neoplasias del Colon/tratamiento farmacológico , Glucósidos/farmacologíaRESUMEN
Bladder cells face a challenging biophysical environment: mechanical cues originating from urine flow and regular contraction to enable the filling voiding of the organ. To ensure functional adaption, bladder cells rely on high biomechanical compliance, nevertheless aging or chronic pathological conditions can modify this plasticity. Obviously the cytoskeletal network plays an essential role, however the contribution of other, closely entangled, intracellular organelles is currently underappreciated. The endoplasmic reticulum (ER) lies at a crucial crossroads, connected to both nucleus and cytoskeleton. Yet, its role in the maintenance of cell mechanical stability is less investigated. To start exploring these aspects, T24 bladder cancer cells were treated with the ER stress inducers brefeldin A (10-40nM BFA, 24 h) and thapsigargin (0.1-100nM TG, 24 h). Without impairment of cell motility and viability, BFA and TG triggered a significant subcellular redistribution of the ER; this was associated with a rearrangement of actin cytoskeleton. Additional inhibition of actin polymerization with cytochalasin D (100nM CytD) contributed to the spread of the ER toward cell periphery, and was accompanied by an increase of cellular stiffness (Young´s modulus) in the cytoplasmic compartment. Shrinking of the ER toward the nucleus (100nM TG, 2 h) was related to an increased stiffness in the nuclear and perinuclear areas. A similar short-term response profile was observed also in normal human primary bladder fibroblasts. In sum, the ER and its subcellular rearrangement seem to contribute to the mechanical properties of bladder cells opening new perspectives in the study of the related stress signaling cascades. Video Abstract.
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Retículo Endoplásmico , Vejiga Urinaria , Humanos , Estrés del Retículo Endoplásmico , Citoesqueleto , Tapsigargina/farmacologíaRESUMEN
The leading first-in-class ruthenium-complex BOLD-100 currently undergoes clinical phase-II anticancer evaluation. Recently, BOLD-100 is identified as anti-Warburg compound. The present study shows that also deregulated lipid metabolism parameters characterize acquired BOLD-100-resistant colon and pancreatic carcinoma cells. Acute BOLD-100 treatment reduces lipid droplet contents of BOLD-100-sensitive but not -resistant cells. Despite enhanced glycolysis fueling lipid accumulation, BOLD-100-resistant cells reveal diminished lactate secretion based on monocarboxylate transporter 1 (MCT1) loss mediated by a frame-shift mutation in the MCT1 chaperone basigin. Glycolysis and lipid catabolism converge in the production of protein/histone acetylation substrate acetyl-coenzymeA (CoA). Mass spectrometric and nuclear magnetic resonance analyses uncover spontaneous cell-free BOLD-100-CoA adduct formation suggesting acetyl-CoA depletion as mechanism bridging BOLD-100-induced lipid metabolism alterations and histone acetylation-mediated gene expression deregulation. Indeed, BOLD-100 treatment decreases histone acetylation selectively in sensitive cells. Pharmacological targeting confirms histone de-acetylation as central mode-of-action of BOLD-100 and metabolic programs stabilizing histone acetylation as relevant Achilles' heel of acquired BOLD-100-resistant cell and xenograft models. Accordingly, histone gene expression changes also predict intrinsic BOLD-100 responsiveness. Summarizing, BOLD-100 is identified as epigenetically active substance acting via targeting several onco-metabolic pathways. Identification of the lipid metabolism as driver of acquired BOLD-100 resistance opens novel strategies to tackle therapy failure.
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Antineoplásicos , Histonas , Compuestos Organometálicos , Humanos , Histonas/metabolismo , Metabolismo de los Lípidos , Acetilación , Acetilcoenzima A/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , LípidosRESUMEN
OBJECTIVES: Pleural mesothelioma (PM) is a rare disease with dismal outcome. Systemic treatment options include chemotherapy and immunotherapy, but biomarkers for treatment personalization are missing. The only FDA-approved diagnostic biomarker is the soluble mesothelin-related protein (SMRP). Krebs von den Lungen-6 (KL-6) is a human mucin 1 (MUC1) glycoprotein, which has shown diagnostic and prognostic value as a biomarker in other malignancies. The present study investigated whether KL-6 can serve as a diagnostic and/or prognostic biomarker in PM. MATERIALS AND METHODS: Using a fully-automated chemiluminescence enzyme immunoassay (CLEIA) for KL-6 and SMRP, pleural effusion samples from 87 consecutive patients with PM and 25 patients with non-malignant pleural disorders were studied. In addition, KL-6 and SMRP levels were determined in corresponding patient sera, and in an independent validation cohort (n = 122). MUC1 mRNA and protein expression, and KL-6 levels in cell line supernatants were investigated in PM primary cell lines in vitro. RESULTS: PM patients had significantly higher KL-6 levels in pleural effusion than non-malignant controls (AUC 0.78, p < 0.0001). Among PM patients, levels were highest in those with epithelioid or biphasic histologies. There was a strong positive correlation between pleural effusion levels of KL-6 and SMRP (p < 0.0001). KL-6 levels in sera similarly associated with diagnosis of PM, however, to a lesser extent (AUC 0.71, p = 0.008). PM patients with high pleural effusion KL-6 levels (≥303 IU/mL) had significantly better overall survival (OS) compared to those with low KL-6 levels (HR 0.51, p = 0.004). Congruently, high tumor cell MUC1 mRNA expression in primary cell lines associated with prolonged corresponding patient OS (HR 0.35, p = 0.004). These findings were confirmed in an independent validation cohort. CONCLUSION: This is the first study demonstrating KL-6 as a potential novel liquid-based diagnostic and prognostic biomarker in PM.
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Pleural mesothelioma (PM) is characterized by poor prognosis and limited therapeutic options. Y-box-binding protein 1 (YB-1) was shown to drive growth and migration of PM cells. Here, we evaluated the effect of genetic and pharmacological targeting of YB-1 on PM growth and response to cisplatin and radiation treatment. YB-1 knockdown via siRNA resulted in reduced PM cell growth, which significantly correlated with wt BAP1 and mutant NF2 and P53 status. Entinostat inhibited YB-1 deacetylation and its efficacy correlated with YB-1 knockdown-induced growth inhibition in 20 PM cell lines. Tumor growth inhibition by siRNA as well as entinostat was confirmed in mouse xenotransplant models. Furthermore, both YBX1-targeting siRNA and entinostat enhanced sensitivity to cisplatin and radiation. In particular, entinostat showed strong synergistic interactions with cisplatin which was linked to significantly increased cellular platinum uptake in all investigated cell models. Importantly, in a mouse model, the combination of cisplatin and entinostat also resulted in stronger growth inhibition than each treatment alone. Our study highlights YB-1 as an attractive target in PM and demonstrates that targeting YB-1 via entinostat is a promising approach to enhance cisplatin and radiation sensitivity.
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Pleural mesothelioma (PM) is an aggressive malignancy that develops in a unique tumor microenvironment (TME). However, cell models for studying the TME in PM are still limited. Here, we have generated and characterized novel human telomerase reverse transcriptase (hTERT)-transduced mesothelial cell and mesothelioma-associated fibroblast (Meso-CAF) models and investigated their impact on PM cell growth. Pleural mesothelial cells and Meso-CAFs were isolated from tissue of pneumothorax and PM patients, respectively. Stable expression of hTERT was induced by retroviral transduction. Primary and hTERT-transduced cells were compared with respect to doubling times, hTERT expression and activity levels, telomere lengths, proteomes, and the impact of conditioned media (CM) on PM cell growth. All transduced derivatives exhibited elevated hTERT expression and activity, and increased mean telomere lengths. Cell morphology remained unchanged, and the proteomes were similar to the corresponding primary cells. Of note, the CM of primary and hTERT-transduced Meso-CAFs stimulated PM cell growth to the same extent, while CM derived from mesothelial cells had no stimulating effect, irrespective of hTERT expression. In conclusion, all new hTERT-transduced cell models closely resemble their primary counterparts and, hence, represent valuable tools to investigate cellular interactions within the TME of PM.
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Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurales , Telomerasa , Humanos , Proteoma/metabolismo , Telomerasa/metabolismo , Mesotelioma/genética , Fibroblastos/metabolismo , Neoplasias Pleurales/genética , Microambiente TumoralRESUMEN
PURPOSE: Resection of high-grade gliomas has been considerably improved by 5-aminolevulinic acid (5-ALA). However, not all neurobiological properties of 5-ALA are fully understood. Specifically, potential differences in immune infiltration have not been conclusively examined, despite recent reports that immune cells might play a role. Thus, we here provide a systematic mapping of immune infiltration of different 5-ALA fluorescence levels. METHODS: Tumor-associated macrophages (CD68, CD163), cytotoxic T cells (CD8), and regulatory T cells (FoxP3) were quantified via three methods. First, data from The Cancer Genome Atlas (TCGA) of 172 patients was examined for correlations between 5-ALA fluorescence-related mRNA expression signatures and immune markers. Second, as classical histology, 508 stained slides from 39 high-grade glioma patients were analysed semi-quantitatively by two independent reviewers, generating 1016 data points. Third, digital image analysis was performed with automated scanning and algorithm-based cell quantification. RESULTS: TCGA mRNA data from 172 patients showed a direct, significant correlation between 5-ALA signatures and immune markers (p < 0.001). However, we were not able to confirm this finding in the here studied initial set of 39 patient histologies where we found a comparable immune infiltration in different fluorescence levels. Digital image analysis correlated excellently with standard histology. CONCLUSION: With mapping the immune infiltration pattern of different 5-ALA categories, we are adding fundamental basic insights to the field of 5-ALA and glioma biology. The observation that a significant correlation in TCGA data did not fully translate to detectable differences in immune infiltration in first histology data warrants further investigation in larger cohorts.
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Neoplasias Encefálicas , Glioma , Humanos , Ácido Aminolevulínico , Neoplasias Encefálicas/patología , Fluorescencia , Glioma/patología , Diagnóstico por Imagen , Biomarcadores/metabolismoRESUMEN
Platinum(iv) prodrugs are a promising class of anticancer agents designed to overcome the limitations of conventional platinum(ii) therapeutics. In this work, we present oxaliplatin(iv)-based complexes, which upon reduction, release acetylsalicylic acid (aspirin), known for its antitumor activity against colon cancer and currently investigated in combination with oxaliplatin in a phase III clinical study. Comparison with a recently reported cisplatin analog (asplatin) revealed a massive increase in reduction stability for the oxaliplatin complex in mouse serum. This was in line with the cell culture data indicating the desired prodrug properties for the newly synthesized complex. For in vivo studies, a new derivative containing an albumin-binding maleimide unit was synthesized. Indeed, distinctly longer plasma half-life as well as higher tumor accumulation in comparison to asplatin and oxaliplatin were observed, also leading to significantly higher antitumor activity and overall survival of CT26 tumor-bearing mice.
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BACKGROUND: Pleural mesothelioma (PM) is a relatively rare malignancy with limited treatment options and dismal prognosis. We have previously found elevated FGF18 expression in PM tissue specimens compared with normal mesothelium. The objective of the current study was to further explore the role of FGF18 in PM and evaluate its suitability as a circulating biomarker. METHODS: FGF18 mRNA expression was analyzed by real-time PCR in cell lines and in silico in datasets from the Cancer Genome Atlas (TCGA). Cell lines overexpressing FGF18 were generated by retroviral transduction and cell behavior was investigated by clonogenic growth and transwell assays. Plasma was collected from 40 PM patients, six patients with pleural fibrosis, and 40 healthy controls. Circulating FGF18 was measured by ELISA and correlated to clinicopathological parameters. RESULTS: FGF18 showed high mRNA expression in PM and PM-derived cell lines. PM patients with high FGF18 mRNA expression showed a trend toward longer overall survival (OS) in the TCGA dataset. In PM cells with low endogenous FGF18 expression, forced overexpression of FGF18 resulted in reduced growth but increased migration. Surprisingly, despite the high FGF18 mRNA levels observed in PM, circulating FGF18 protein was significantly lower in PM patients and patients with pleural fibrosis than in healthy controls. No significant association of circulating FGF18 with OS or other disease parameters of PM patients was observed. CONCLUSIONS: FGF18 is not a prognostic biomarker in PM. Its role in PM tumor biology and the clinical significance of decreased plasma FGF18 in PM patients warrant further investigation.
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Neoplasias Pulmonares , Mesotelioma Maligno , Mesotelioma , Neoplasias Pleurales , Humanos , Fibrosis , Neoplasias Pulmonares/patología , Mesotelioma/genética , Mesotelioma/patología , Neoplasias Pleurales/genética , Neoplasias Pleurales/patología , Pronóstico , ARN Mensajero/genéticaRESUMEN
Based on their drug delivery properties and activity against tumors, we combined PAMAM dendrimers with various platinum(IV) complexes in order to provide an improved approach of anticancer treatment. Platinum(IV) complexes were linked to terminal NH2 moieties of PAMAM dendrimers of generation 2 (G2) and 4 (G4) via amide bonds. Conjugates were characterized by 1H and 195Pt NMR spectroscopy, ICP-MS and in representative cases by pseudo-2D diffusion-ordered NMR spectroscopy. Additionally, the reduction behavior of conjugates in comparison to corresponding platinum(IV) complexes was investigated, showing a faster reduction of conjugates. Cytotoxicity was evaluated via the MTT assay in human cell lines (A549, CH1/PA-1, SW480), revealing IC50 values in the low micromolar to high picomolar range. The synergistic combination of PAMAM dendrimers and platinum(IV) complexes resulted in up to 200 times increased cytotoxic activity of conjugates in consideration of the loaded platinum(IV) units compared to their platinum(IV) counterparts. The lowest IC50 value of 780 ± 260 pM in the CH1/PA-1 cancer cell line was detected for an oxaliplatin-based G4 PAMAM dendrimer conjugate. Finally, in vivo experiments of a cisplatin-based G4 PAMAM dendrimer conjugate were performed based on the best toxicological profile. A maximum tumor growth inhibition effect of 65.6% compared to 47.6% for cisplatin was observed as well as a trend of prolonged animal survival.
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Small-molecule EGFR inhibitors have distinctly improved the overall survival especially in EGFR-mutated lung cancer. However, their use is often limited by severe adverse effects and rapid resistance development. To overcome these limitations, a hypoxia-activatable Co(III)-based prodrug (KP2334) was recently synthesized releasing the new EGFR inhibitor KP2187 in a highly tumor-specific manner only in hypoxic areas of the tumor. However, the chemical modifications in KP2187 necessary for cobalt chelation could potentially interfere with its EGFR-binding ability. Consequently, in this study, the biological activity and EGFR inhibition potential of KP2187 was compared to clinically approved EGFR inhibitors. In general, the activity as well as EGFR binding (shown in docking studies) was very similar to erlotinib and gefitinib (while other EGFR-inhibitory drugs behaved different) indicating no interference of the chelating moiety with the EGFR binding. Moreover, KP2187 significantly inhibited cancer cell proliferation as well as EGFR pathway activation in vitro and in vivo. Finally, KP2187 proved to be highly synergistic with VEGFR inhibitors such as sunitinib. This indicates that KP2187-releasing hypoxia-activated prodrug systems are promising candidates to overcome the clinically observed enhanced toxicity of EGFR-VEGFR inhibitor combination therapies.
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Antineoplásicos , Neoplasias Pulmonares , Profármacos , Humanos , Profármacos/farmacología , Profármacos/uso terapéutico , Receptores ErbB/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Clorhidrato de Erlotinib/farmacología , Neoplasias Pulmonares/metabolismo , Proliferación Celular , Hipoxia/metabolismo , Línea Celular Tumoral , Antineoplásicos/uso terapéuticoRESUMEN
In this study, we present a workflow that enables spatial single-cell metallomics in tissue decoding the cellular heterogeneity. Low-dispersion laser ablation in combination with inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-TOFMS) provides mapping of endogenous elements with cellular resolution at unprecedented speed. Capturing the heterogeneity of the cellular population by metals only is of limited use as the cell type, functionality, and cell state remain elusive. Therefore, we expanded the toolbox of single-cell metallomics by integrating the concepts of imaging mass cytometry (IMC). This multiparametric assay successfully utilizes metal-labeled antibodies for cellular tissue profiling. One important challenge is the need to preserve the original metallome in the sample upon immunostaining. Therefore, we studied the impact of extensive labeling on the obtained endogenous cellular ionome data by quantifying elemental levels in consecutive tissue sections (with and without immunostaining) and correlating elements with structural markers and histological features. Our experiments showed that the elemental tissue distribution remained intact for selected elements such as sodium, phosphorus, and iron, while absolute quantification was precluded. We hypothesize that this integrated assay not only advances single-cell metallomics (enabling to link metal accumulation to multi-dimensional characterization of cells/cell populations), but in turn also enhances selectivity in IMC, as in selected cases, labeling strategies can be validated by elemental data. We showcase the power of this integrated single-cell toolbox using an in vivo tumor model in mice and provide mapping of the sodium and iron homeostasis as linked to different cell types and function in mouse organs (such as spleen, kidney, and liver). Phosphorus distribution maps added structural information, paralleled by the DNA intercalator visualizing the cellular nuclei. Overall, iron imaging was the most relevant addition to IMC. In tumor samples, for example, iron-rich regions correlated with high proliferation and/or located blood vessels, which are key for potential drug delivery.
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This study reports a dose-dependent pro-apoptotic action of synthetic cannabimimetic N-stearoylethanolamine (NSE) on diverse cancer cell lines, including multidrug-resistant models. No antioxidant or cytoprotective effects of NSE were found when it was applied together with doxorubicin. A complex of NSE with the polymeric carrier poly(5-(tert-butylperoxy)-5-methyl-1-hexen-3-yn-co-glycidyl methacrylate)-graft-PEG was synthesized. Co-immobilization of NSE and doxorubicin on this carrier led to a 2-10-fold enhancement of the anticancer activity, particularly, against drug-resistant cells overexpressing ABCC1 and ABCB1. This effect might be caused by accelerated nuclear accumulation of doxorubicin in cancer cells, which led to the activation of the caspase cascade, revealed by Western blot analysis. The NSE-containing polymeric carrier was also able to significantly enhance the therapeutic activity of doxorubicin in mice with implanted NK/Ly lymphoma or L1210 leukemia, leading to the complete eradication of these malignancies. Simultaneously, loading to the carrier prevented doxorubicin-induced elevation of AST and ALT as well as leukopenia in healthy Balb/c mice. Thus, a unique bi-functionality of the novel pharmaceutical formulation of NSE was revealed. It enhanced doxorubicin-induced apoptosis in cancer cells in vitro and promoted its anticancer activity against lymphoma and leukemia models in vivo. Simultaneously, it was very well tolerated preventing frequently observed doxorubicin-associated adverse effects.