Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal cancers, as the most effective chemoradiation therapies achieve unsatisfactory outcomes while associated with high toxicity. Nanoliposomal drug delivery systems are widely used to improve chemotherapy safety, yet passive release of amphiphilic drugs may still associate with adverse toxicity. To address this, we previously developed nanoliposomes functionalized with hydrophobic gold nanoclusters, demonstrating radiocatalytic activity and enhanced chemoradiotherapy effects in 3D PDAC microtumors under synchrotron irradiation. In this study, gold nanocluster-functionalized nanoliposomes (AuLPs) were optimized and evaluated under 220 kVp orthovoltage X-ray irradiation, widely used in preclinical irradiation systems. AuLPs containing 0.2 mol% gold nanoclusters produced 1.5-fold more reactive oxygen species than unloaded liposomes. However, higher molar ratios were necessary to improve radiotherapy outcomes in 3D PDAC microtumor models following 4 and 8 Gy irradiation. Pharmacokinetics and biodistribution evaluations showed a modest increase in tumor gold content 24 hours post-injection in orthotopic PDAC models. Altogether, these results underscore the potential of gold-radiotherapy-responsive liposomes while highlighting critical formulation challenges, which must be resolved for full therapeutic potential.

Aza-boron-dipyrromethenes (aza-BODIPYs) are established fluorescent imaging agents derived from aza-DIPY ligands coordinated to boron. While many modifications of the aza-DIPY core have optimized the photophysical properties, replacing boron with a metal ion remains underexplored. Here, we report four zirconium-based aza-DIPY complexes (aza-ZrDIPYs) and show that this substitution enables bimodal NIR-I fluorescence and photoacoustic imaging. The complexes were fully characterized and evaluated photophysiologically. The bromo derivative, aza-ZrDIPY-Br, displayed particularly favorable dual-mode properties. It showed low in vitro cytotoxicity and an effective uptake in two human cell lines. In mice bearing subcutaneous U87-MG glioblastoma tumors, intravenous or peritumoral administration led to passive tumor accumulation, with tumor-to-background ratios of up to 5 (photoacoustic) and 2 (optical). These results highlight aza-ZrDIPY-Br as a promising bimodal probe for tumor imaging, with future work aimed at improving specificity through active targeting.

The study reports the synthesis and biological evaluation of [111In]In-WAZABY, a novel bimodal imaging probe based on a water-soluble NIR-II aza-BODIPY fluorophore. The platform enables the design of a bimodal imaging probe through conjugation to the anti-epithelial growth factor receptor (EGFR) antibody cetuximab and incorporation of a [111In]In-DOTA complex for single-photon emission computed tomography (SPECT) imaging. The resulting probe efficiently targets EGFR-expressing tumors in a murine model of head and neck squamous cell carcinoma (HSNCC). Multimodal imaging combining NIR-I/NIR-II fluorescence and SPECT revealed specific tumor accumulation and a strong spatial correlation between optical and SPECT signals, demonstrating that DOTA grafting does not compromise fluorophore behavior or in vivo stability. These results establish [111In]In-WAZABY as a promising dual-modality contrast agent for peroperative tumor localization and future fluorescence-guided surgery (FGS), enabling complementary deep-tissue and high-resolution imaging.

Aza-boron-dipyrromethenes (aza-BODIPYs) are established fluorescent imaging agents derived from aza-DIPY ligands coordinated to boron. While many modifications of the aza-DIPY core have optimized the photophysical properties, replacing boron with a metal ion remains underexplored. Here, we report four zirconium-based aza-DIPY complexes (aza-ZrDIPYs) and show that this substitution enables bimodal NIR-I fluorescence and photoacoustic imaging. The complexes were fully characterized and evaluated photophysiologically. The bromo derivative, aza-ZrDIPY-Br, displayed particularly favorable dual-mode properties. It showed low in vitro cytotoxicity and an effective uptake in two human cell lines. In mice bearing subcutaneous U87-MG glioblastoma tumors, intravenous or peritumoral administration led to passive tumor accumulation, with tumor-to-background ratios of up to 5 (photoacoustic) and 2 (optical). These results highlight aza-ZrDIPY-Br as a promising bimodal probe for tumor imaging, with future work aimed at improving specificity through active targeting.

Copper is an essential trace element for life and is present in the active site of various enzymes, whereas free copper is toxic to cells. Copper homeostasis is thus finely regulated, involving Cu(I) transporting membrane proteins Ctr1 and ATP7A/B. Disruption of copper homeostasis has been reported as a potential anticancer strategy. With this objective, we have developed a family of lipophilic compounds featuring two preorganized coordinating (benz)imidazole groups designed biomimetically to bind Cu(I) in a linear geometry and function as ionophores. The transport of Cu(I) cations across membranes by these compounds was first demonstrated in liposomes using an encapsulated Cu(I) sensitive fluorescent probe. Furthermore, six of the ionophores restored the growth of yeast cells lacking Ctr1, indicating their ability to also transport copper into cells. In hepatocarcinoma cells, four of these six ionophores exhibited potent anticancer activity, with IC50 values ranging from 3 to 5 μM. These active ionophores share a relatively narrow lipophilicity range (cLogP = 7-9.2), underscoring the critical role of lipophilicity in their cellular activity. Further investigations of one of the most active compounds, named Cuphoralix, revealed no increase in intracellular Cu levels in hepatocytes but clear indications of metal-induced stress. State-of-the-art synchrotron X-ray fluorescence studies demonstrated that Cuphoralix alters the subcellular copper distribution, redistributing it from the vesicles to the cytosol. This redistribution likely accounts for the potent cytotoxicity of this novel class of Cu(I) ionophores, supporting further studies on their anticancer potential.

Lipid bilayers are impermeable to ions, including copper cations. Copper is an essential trace element for life, present in the active site of various enzymes, whereas free copper is detrimental inside cells. Copper homeostasis is thus finely controlled, involving Cu(I) transporting membrane proteins Ctr1 and ATP7A/B. Disruption of copper homeostasis has been reported as a potential anti-cancer strategy. With this objective, we have developed a series of lipophilic compounds with two copper coordinating (benz)imidazole groups that are able to function as ionophores, transporting copper cations across membranes. This was firstly demonstrated in liposomes with a Cu(I) sensitive fluorescent probe encapsulated. Secondly, five of these compounds were shown to restore the growth of yeast cells that had Ctr1 deleted, suggesting that these ionophores were able to transport copper into yeast cells. Thirdly, cytotoxicity studies in hepatocarcinoma cells highlighted the crucial role of the lipophilicity of Cu ionophores for their activity in cells. The impact of one of the most active compounds, named Cuphoralix, was further studied, showing no increase of intracellular Cu levels of the hepatocytes, but clear indications of metallic stress. Synchrotron X-ray fluorescence studies were then employed to study the effect of Cuphoralix on the subcellular copper distribution, revealing a redistribution of copper from vesicles to the cytosol. This explains the potent cytotoxicity of this novel class of copper ionophores, warranting further studies of their anti-cancer effects.

Gene and RNA-based therapeutics represent a promising frontier in oncology, enabling targeted modulation of tumor-associated genes and proteins. This review explores the latest advances in payload vectorization and delivery systems developed for in vivo cancer treatments. We discuss viral and non-viral organic particles, including lipid based nanoparticles and polymeric structures, for the effective transport of plasmids, siRNA, and self-amplifying RNA therapeutics. Their physicochemical properties, strategies to overcome intracellular barriers, and innovations in cell-based carriers and engineered extracellular vesicles are highlighted. Moreover, we consider oncolytic viruses, novel viral capsid modifications, and approaches that refine tumor targeting and immunomodulation. Ongoing clinical trials and regulatory frameworks guide future directions and emphasize the need for safe, scalable production. The potential convergence of these systems with combination therapies paves the way toward personalized cancer medicine.

Chemoradiation therapy is on the forefront of pancreatic cancer care, and there is a continued effort to improve its safety and efficacy. Liposomes are widely used to improve chemotherapy safety, and may accurately deliver high-Z element- radiocatalytic nanomaterials to cancer tissues. In this study, the interaction between X-rays and long-circulating nanoliposome formulations loaded with gold nanoclusters is explored in the context of oxaliplatin chemotherapy for desmoplastic pancreatic cancer. Hydrophobic gold nanoclusters stabilized with dodecanethiol (AuDDT) are efficiently incorporated in nanoliposomal bilayers. AuDDT-nanoliposomes significantly augmented radiation-induced • OH production, which is most effective with monochromatic X-rays at energies that exceed the K-shell electron binding energy of Au (81.7 keV). Cargo release assays reveal that AuDDT-nanoliposomes can permeabilize lipid bilayers in an X-ray dose- and formulation-dependent manner. The radiocatalytic effect of AuDDT-nanoliposomes significantly augments radiotherapy and oxaliplatin-chemoradiotherapy outcomes in 3D pancreatic microtumors. The PEGylated AuDDT-nanoliposomes display high tumor accumulation in an orthotopic mouse model of pancreatic cancer, showing promise for nanoliposomes as carriers for radiocatalytic nanomaterials. Altogether, compelling proof for chemo-radiation dose-enhancement using AuDDT-nanoliposomes is presented. Further improving the nanoliposomal loading of high-Z elements will advance the safety, efficacy, and translatability of such chemoradiation dose-enhancement approaches.

Laser-induced breakdown spectroscopy (LIBS) imaging continues to gain strength as an influential bioanalytical technique, showing intriguing potential in the field of clinical analysis. This is because hyperspectral LIBS imaging allows for rapid, comprehensive elemental analysis, covering elements from major to trace levels consistently year after year. In this study, we estimated the potential of a multivariate spectral data treatment approach based on a so-called convex envelope method to detect exotic elements (whether they are minor or in trace amounts) in biopsy tissues of patients with occupational exposure-related diseases. More precisely, we have developed an approach called Interesting Features Finder (IFF), which initially allowed us to identify unexpected elements without any preconceptions, considering only the set of spectra contained in a LIBS hyperspectral data cube. This task is, in fact, almost impossible with conventional chemometric tools, as it entails identifying a few exotic spectra among several hundred thousand others. Once this detection was performed, a second approach based on correlation was used to locate their distribution in the biopsies. Through this unique data analysis pipeline to processing massive LIBS spectroscopic data, it was possible to detect and locate exotic elements such as tin and rhodium in a patient's tissue section, ultimately leading to a possible reclassification of their lung condition as an occupational disease. This review will thus demonstrate the potential of this new diagnostic tool based on LIBS imaging in addressing the shortcomings of approaches developed thus far. The proposed data processing approach naturally transcends this specific framework and can be leveraged across various domains of analytical chemistry, where the detection of rare events is concealed within extensive data sets.

Occupational and environmental exposures, particularly those related to urban and suburban atmospheres, are increasingly linked to a range of pulmonary diseases. While diagnostic methods for these diseases are well established, analytical tools for assessing elemental contamination in lung tissue remain underutilized. This study introduces a novel framework based on laser‐induced breakdown spectroscopy (LIBS) for the in situ quantification of elemental titanium (Ti) in lung tissues from both animal models and human specimens. Rigorous validation is conducted using animal models exposed to TiO2 P25 nanoparticles and a comparative analysis with inductively coupled plasma mass spectrometry. The novel quantitative metric demonstrates robust correlation with elemental concentrations, expanding LIBS utility to volumetric organ analysis. This validated methodology is subsequently applied to human lung specimens preserved in paraffin. The research holds significant promise as a diagnostic tool for assessing exposure levels to environmental or occupational hazards, thereby offering valuable contributions to the fields of toxicology and respiratory medicine.

The development of new fluorescent organic probes effective in the NIR-II region is currently a fast-growing field and represents a challenge in the domain of medical imaging. In this study, we have designed and synthesized an innovative series of aza-boron dipyrromethenes emitting in the NIR-II region. We have investigated the effect of different water-solubilizing groups not only on the photophysical properties of the compounds but also on their in vitro and in vivo performance after bioconjugation to the antibody trastuzumab. Remarkably, we discovered that the most lipophilic compound unexpectedly displayed the most favorable in vivo properties after bioconjugation. This underlines the profound influence that the fluorophore functionalization approach can have on the efficiency of the resulting imaging agent.

Abstract Introduction: Cuproptosis is a novel programmed cell death pathway triggered by increased intracellular Copper (Cu) levels. This process offers promising avenues for cancer therapy and underscores the pivotal role of Cu-targeting molecules, such as chelators and ionophores. Despite the progress made, there is still a critical need for novel molecules capable of disrupting copper homeostasis within cancer cells. Methods: We developed and patented a novel class of Cu(I) ionophores characterized by calix[4]arene structures. The anticancer effects of these compounds were evaluated through proliferation assays (IC50), cell cycle assays, and the mechanisms of cell death were explored, including apoptosis, senescence, autophagy, and cuproptosis. To elucidate the mechanisms of action, we conducted proteomic and phosphoproteomic analyses in three different lung adenocarcinoma cell lines (A549, H322, and PC9). Intracellular concentrations of Zn, Fe, and Cu were determined by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Animal experiments were conducted on nude mice bearing subcutaneous A549 lung cancer xenografts. Results: Our lead compound, Cuphoralix, demonstrated potent cytostatic effect across a panel of 60 cancer cell lines. This effect was attributed to an early and irreversible blockade of the cell cycle initiation at 24 hours post-treatment. Cuphoralix treatment did not induce senescence or apoptosis. Proteomic analyses confirmed the differential regulation—both upregulation and downregulation—of over 500 proteins and phosphopeptides following treatment with Cuphoralix. Notably, Cuphoralix treatment resulted in decreased expression levels of proteins implicated in cell cycle progression and DNA replication. We discovered that Cuphoralix induced cuproptosis and autophagy, as evidenced by the overexpression of LC3B-II. Intracellular Cu level was significantly increased after treatment with Cuphoralix, suggesting the initiation of cuproptosis. In vivo, the toxicity of liposomal Cuphoralix was assessed following three intravenous injections/week for 4 weeks. Animal weights remained stable, with no observed toxicity or signs of neurological or functional impairment. The anticancer efficacy of Cuphoralix, both alone and in combination with other treatments, was corroborated in vivo by measuring the volumes of subcutaneous xenografts. Conclusions: Our novel Cu(I) ionophore, Cuphoralix, has demonstrated significant potential in inducing cuproptosis and disrupting copper homeostasis, presenting a novel approach to cancer therapy. The compound's capacity to initiate an early and irreversible cell cycle blockade and to modulate the expression of key proteins underscores its therapeutic promise. The profound in vitro and in vivo anticancer effects observed encourage further development and investigation of cuproptosis as a targeted cancer treatment strategy. Citation Format: Pierre Lelievre, Cyril Nogier, Nathan Renier, Jean-Luc Coll, Ivan Jabin, Lucie Sancey, Hennie Valkenier, Aurelien Deniaud, Benoit Busser. Unlocking the anticancer potential of calix[4]arene-based Cu(I) ionophores in vitro and in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4681.

Aza-BODIPYs represent a class of fluorophores in which the π-conjugated system is rigidified and stabilized by a boron atom. A promising strategy to enhance their fluorescence properties involves replacing the boron atom with a metal ion. Here, we describe the synthesis and characterization of a water-soluble derivative where the metal is a gallium(III) ion, termed WazaGaY (water-soluble aza-GaDIPY). Water solubility is ensured by two ammonium substituents, inducing a bathochromic shift and a significant increase in quantum yield compared to that of the dimethylamino analog. The cellular behavior of WazaGaY-1 was observed across different tumor cells. In vivo, the distribution and safety profiles were determined, and tumor uptake was assessed in various tumor types. Following intravenous injection, WazaGaY-1 enabled clear discrimination of tumors engrafted subcutaneously in mice with high tumor-to-muscle ratios (ranging from 7 to 20), even in the absence of specific conjugation. Its potential as a contrast agent for fluorescence-guided surgery was confirmed.

Zinc (Zn) is a crucial trace element involved in various cellular processes, including oxidative stress, apoptosis and immune response, contributing to cellular homeostasis. Dysregulation of Zn homeostasis occurs in certain cancers. This review discusses the role of Zn in cancer and its associated components, such as Zn-related proteins, their potential as biomarkers and the use of Zn-based strategies for tumor treatment. ZIP and ZnT proteins regulate Zn metabolism under normal conditions, but their expression is aberrant in cancer. These Zn proteins can serve as prognostic or diagnostic biomarkers, aiding in early cancer detection and disease monitoring. Moreover, targeting Zn and its pathways offers potential therapeutic approaches for cancer treatment. Modulating Zn biodistribution within cells using metal-binding agents allows for the control of downstream signaling pathways. Direct utilization of zinc as a therapeutic agent, including Zn supplementation or Zn oxide nanoparticle administration, holds promise for improving the prognosis of cancer patients.

Aza-boron-dipyrromethenes (Aza-BODIPYs) are an increasingly studied class of fluorophores. They can be seen as an azadipyrromethene ("aza-DIPY") ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. The impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined, and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) makes them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this redshift seems to be more due to the geometry around the boron/metal than to the nature of the metal.

Using fluorescence-guided surgery (FGS) to cytoreductive surgery helps achieving complete resection of microscopic ovarian tumors. The use of visible and NIR-I fluorophores has led to beneficial results in clinical trials; however, involving NIR-II dyes seems to outperform those benefits due to the deeper tissue imaging and higher signal/noise ratio attained within the NIR-II optical window. In this context, we developed NIR-II emitting dyes targeting human epidermal growth factor receptor 2 (HER2)-positive ovarian tumors by coupling water-soluble NIR-II aza-BODIPY dyes to the FDA-approved anti-HER2 antibody, namely, trastuzumab. These bioconjugated NIR-II-emitting dyes displayed a prolonged stability in serum and a maintained affinity toward HER2 in vitro. We obtained selective targeting of HER2 positive tumors (SKOV-3) in vivo, with a favorable tumor accumulation. We demonstrated the fluorescence properties and the specific HER2 binding of the bioconjugated dyes in vivo and thus their potential for NIR-II FGS in the cancer setting.

Laser-induced breakdown spectroscopy (LIBS) is a versatile analytical tool for studying the elemental composition of any kind of sample, such as solids, liquids or gases.One of the latest developments in this technique is the ability to use it for elemental imaging, that is to say spatially resolved surface analysis.LIBS imaging is becoming a very attractive and popular technique for the qualitative and/or quantitative spectrochemical characterization of specimens for a wide range of applications.Because of its unique set of intrinsic advantages, LIBS imaging is frequently preferred over competitive and complementary techniques for elemental imaging.This review recapitulates the technical fundamentals of LIBS imaging and focuses on significant applications that have received the most promising attention and have undergone major advances during the last three years in the industrial, geological and biomedical fields.We also discuss the current limitations that hinder the further development of LIBS imaging, as well as perspectives on the use of LIBS as a part of multimodal imaging strategies, the contribution of chemometrics, and ideas for improving the limits of detection and quantification aspects.

SuccFerr (N-[4-ferrocenyl,5-5-bis (4-hydroxyphenyl)-pent-4-enyl]-succinimide) has remarkable antiproliferative effects in vitro, attributed to the formation of a stabilized quinone methide. The present article reports in vivo results for a possible preclinical study. SuccFerr is lipophilic and insoluble in water, so the development of a formulation to obviate this inconvenience was necessary. This was achieved by complexation with randomly methylated cyclodextrins (RAMEßCDs). This supramolecular water-soluble system allowed the in vivo experiments below to proceed. Application of SuccFerr on the glioblastoma cancer cell line U87 indicates that it affects the cellular cycle by inducing a blockade at G0/G1 phase, linked to apoptosis, and another one at the S phase, associated with senescence. Using healthy Fischer rats, we show that both intravenous and subcutaneous SuccFerr: RAMEßCD administration at 5 mg/kg lacks toxic effects on several organs. To reach lethality, doses higher than 200 mg/kg need to be administered. These results prompted us to perform an ectopic in vivo study at 1 mg/kg i.v. ferrocidiphenol SuccFerr using F98 cells xenografted in rats. Halting of cancer progression was observed after six days of injection, associated with an immunological defense response linked to the active principle. These results demonstrate that the properties of the selected ferrocidiphenol SuccFerr transfer successfully to in vivo conditions, leading to interesting therapeutic perspectives based on this chemistry.