Metal complex-based liposomes: Applications and prospects in cancer diagnostics and therapeutics

Acidity-activatable dynamic hybrid nanoplatforms derived from extracellular vesicles of M1 macrophages enhance cancer immunotherapy through synergistic triple immunotherapy

Immunotherapy exhibits considerable promise for sustained tumor reduction. However, current cancer immunotherapy methods elicit limited responses due to the inadequate immunogenicity exhibited by cancer cells. This obstacle may be addressed using nanoplatforms that can activate synergistic therapies (photodynamic therapy and ferroptosis) in response to the acidic pH of the tumor microenvironment. We previously developed an amphiphilic photosensitizer, SR780, which displays satisfactory photodynamic effects. This photosensitizer is inactivated when bound to Fe3+ (SR780Fe) but is activated upon release in mildly acidic conditions. In this study, M1 macrophage-derived extracellular vesicles (EVs) were fused with REV and SR780Fe-loaded liposomes (REV@SR780Fe@Lip) to form REV@SR780Fe@LEV hybrid nanovesicles. Further modification with the RS17 peptide for tumor targeting enabled a combination of photodynamic therapy, ferroptosis, and cGAS-STING pathway activation, resulting in enhanced antitumor efficacy through a synergistic effect. Upon laser irradiation, REV@SR780Fe@LEV-RS17 demonstrated antitumor effects in 4T1 breast cancer models, including the inhibition of lung and liver metastasis, as well as prevention of tumor recurrence.

Oral Nanomedicine: Challenges and Opportunities

Compared to injection administration, oral administration is free of discomfort, wound infection, and complications and has a higher compliance rate for patients with diverse diseases. However, oral administration reduces the bioavailability of medicines, especially biologics (e.g., peptides, proteins, and antibodies), due to harsh gastrointestinal biological barriers. In this context, the development and prosperity of nanotechnology have helped improve the bioactivity and oral availability of oral medicines. On this basis, first, the biological barriers to oral administration are discussed, and then oral nanomedicine based on organic and inorganic nanomaterials and their biomedical applications in diverse diseases are reviewed. Finally, the challenges and potential opportunities in the future development of oral nanomedicine, which may provide a vital reference for the eventual clinical transformation and standardized production of oral nanomedicine, are put forward.

Leptomeningeal disease in melanoma: An update on the developments in pathophysiology and clinical care

Leptomeningeal disease (LMD) remains a major challenge in the clinical management of metastatic melanoma patients. Outcomes for patient remain poor, and patients with LMD continue to be excluded from almost all clinical trials. However, recent trials have demonstrated the feasibility of conducting prospective clinical trials in these patients. Further, new insights into the pathophysiology of LMD are identifying rational new therapeutic strategies. Here we present recent advances in the understanding of, and treatment options for, LMD from metastatic melanoma. We also annotate key areas of future focus to accelerate progress for this challenging but emerging field.

Chemotherapeutic Activity of Imidazolium-Supported Pd(II) o-Vanillylidene Diaminocyclohexane Complexes Immobilized in Nanolipid as Inhibitors for HER2/neu and FGFR2/FGF2 Axis Overexpression in Breast Cancer Cells

Two bis-(imidazolium-vanillylidene)-(R,R)-diaminocyclohexane ligands (H2(VAN)2dach, H2L1,2) and their Pd(II) complexes (PdL1 and PdL2) were successfully synthesized and structurally characterized using microanalytical and spectral methods. Subsequently, to target the development of new effective and safe anti-breast cancer chemotherapeutic agents, these complexes were encapsulated by lipid nanoparticles (LNPs) to formulate (PdL1LNP and PdL2LNP), which are physicochemically and morphologically characterized. PdL1LNP and PdL2LNP significantly cause DNA fragmentation in MCF-7 cells, while trastuzumab has a 10% damaging activity. Additionally, the encapsulated Pd1,2LNPs complexes activated the apoptotic mechanisms through the upregulated P53 with p < 0.001 and p < 0.05, respectively. The apoptotic activity may be triggered through the activity mechanism of the Pd1,2LNPs in the inhibitory actions against the FGFR2/FGF2 axis on the gene level with p < 0.001 and the Her2/neu with p < 0.05 and p < 0.01. All these aspects have triggered the activity of the PdL1LNP and PdL2LNP to downregulate TGFβ1 by p < 0.01 for both complexes. In conclusion, LNP-encapsulated Pd(II) complexes can be employed as anti-cancer drugs with additional benefits in regulating the signal mechanisms of the apoptotic mechanisms among breast cancer cells with chemotherapeutic-safe actions.

Recent Breakthroughs in Using Quantum Dots for Cancer Imaging and Drug Delivery Purposes

Cancer is one of the leading causes of death worldwide. Because each person's cancer may be unique, diagnosing and treating cancer is challenging. Advances in nanomedicine have made it possible to detect tumors and quickly investigate tumor cells at a cellular level in contrast to prior diagnostic techniques. Quantum dots (QDs) are functional nanoparticles reported to be useful for diagnosis. QDs are semiconducting tiny nanocrystals, 2-10 nm in diameter, with exceptional and useful optoelectronic properties that can be tailored to sensitively report on their environment. This review highlights these exceptional semiconducting QDs and their properties and synthesis methods when used in cancer diagnostics. The conjugation of reporting or binding molecules to the QD surface is discussed. This review summarizes the most recent advances in using QDs for in vitro imaging, in vivo imaging, and targeted drug delivery platforms in cancer applications.

Extracellular Vesicles-Derived Hybrid Nanoplatforms for Amplified CD47 Blockade-Based Cancer Immunotherapy

Immunomodulation of tumor-associated macrophages (TAMs) into tumor-inhibiting M1-like phenotype is a promising but challenging strategy. Cleverly, tumor cells overexpress CD47, a "don't eat me" signal that ligates with the signal regulatory protein alpha (SIRPα) on macrophages to escape phagocytosis. Thus, effective re-education of TAMs into the "eat me" type and blocking the CD47-SIRPα signaling play pivotal roles in tumor immunotherapy. Herein, it is reported that hybrid nanovesicles (hEL-RS17) derived from extracellular vesicles of M1 macrophages and decorated with RS17 peptide, an antitumor peptide that specifically binds to CD47 on tumor cells and blocks CD47-SIRPα signaling, can actively target tumor cells and remodel TAM phenotypes. Consequently, more M1-like TAMs infiltrate into tumor tissue to phagocytize more tumor cells due to CD47 blockade. By further co-encapsulating chemotherapeutic agent shikonin, photosensitizer IR820, and immunomodulator polymetformin in hEL-RS17, an enhanced antitumor effect is obtained due to the combinational treatment modality and close synergy among each component. Upon laser irradiation, the designed SPI@hEL-RS17 nanoparticles exert potent antitumor efficacy against both 4T1 breast tumor and B16F10 melanoma models, which not only suppresses primary tumor growth but also inhibits lung metastasis and prevents tumor recurrence, exhibiting great potential in boosting CD47 blockade-based antitumor immunotherapy.

Nanomaterials in tumor immunotherapy: new strategies and challenges

Tumor immunotherapy exerts its anti-tumor effects by stimulating and enhancing immune responses of the body. It has become another important modality of anti-tumor therapy with significant clinical efficacy and advantages compared to chemotherapy, radiotherapy and targeted therapy. Although various kinds of tumor immunotherapeutic drugs have emerged, the challenges faced in the delivery of these drugs, such as poor tumor permeability and low tumor cell uptake rate, had prevented their widespread application. Recently, nanomaterials had emerged as a means for treatment of different diseases due to their targeting properties, biocompatibility and functionalities. Moreover, nanomaterials possess various characteristics that overcome the defects of traditional tumor immunotherapy, such as large drug loading capacity, precise tumor targeting and easy modification, thus leading to their wide application in tumor immunotherapy. There are two main classes of novel nanoparticles mentioned in this review: organic (polymeric nanomaterials, liposomes and lipid nanoparticles) and inorganic (non-metallic nanomaterials and metallic nanomaterials). Besides, the fabrication method for nanoparticles, Nanoemulsions, was also introduced. In summary, this review article mainly discussed the research progress of tumor immunotherapy based on nanomaterials in the past few years and offers a theoretical basis for exploring novel tumor immunotherapy strategies in the future.

Drug complexes: Perspective from Academic Research and Pharmaceutical Market

Despite numerous research efforts, drug delivery through the oral route remains a major challenge to formulation scientists. The oral delivery of drugs poses a significant challenge because more than 40% of new chemical entities are practically insoluble in water. Low aqueous solubility is the main problem encountered during the formulation development of new actives and for generic development. A complexation approach has been widely investigated to address this issue, which subsequently improves the bioavailability of these drugs. This review discusses the various types of complexes such as metal complex (drug-metal ion), organic molecules (drug-caffeine or drug-hydrophilic polymer), inclusion complex (drug-cyclodextrin), and pharmacosomes (drug-phospholipids) that improves the aqueous solubility, dissolution, and permeability of the drug along with the numerous case studies reported in the literature. Besides improving solubility, drug-complexation provides versatile functions like improving stability, reducing the toxicity of drugs, increasing or decreasing the dissolution rate, and enhancing bioavailability and biodistribution. Apart, various methods to predict the stoichiometric ratio of reactants and the stability of the developed complex are discussed.

Anticancer Activities of Re(I) Tricarbonyl and Its Imidazole-Based Ligands: Insight from a Theoretical Approach

Rhenium complexes have been observed experimentally to exhibit good inhibitory activity against malignant cells. Hence, our motivation is to explore this activity from a theoretical perspective. In the present study, density functional theory (DFT) and in silico molecular docking approaches were utilized to unravel the unique properties of metal-based rhenium tricarbonyl complexes as effective anticancer drugs. All DFT calculations and geometric optimizations were conducted using the well-established hybrid functional B3LYP-GD(BJ)/Gen/6-311++G(d,p)/LanL2DZ computational method. The FT-IR spectroscopic characterization of the complexes: fac-[Re(Pico)(CO)₃(Pz)] (R1), fac-[Re(Pico)(CO)₃(Py)] (R2), fac-[Re(Dfpc)(CO)₃(H₂O)] (R3), fac-[Re(Dfpc)(CO)₃(Pz)] (R4), fac-[Re(Dfpc)(CO)₃(Py)] (R5), fac-[Re(Tfpc)(CO)₃(H₂O)] (R6), fac-[Re(Tfpc)(CO)₃(Py)] (R7), and fac-[Re(Tfpc)(CO)₃(Im)] (R8) was explored. To gain insights into the electronic structural properties, bioactivity, and stability of these complexes, the highest occupied molecular orbital-lowest unoccupied molecular orbital analysis, binding energy, and topological analysis based on quantum theory of atoms-in-molecules were considered. The anticancer activities of the complexes were measured via in silico molecular docking against human BCL-2 protein (IG5M) and proapoptotic (agonist) BAX 1 protein (450O). The results showed that the studied complexes exhibited good binding affinity (-3.25 to -10.16 kcal/mol) and could cause significant disruption of the normal physiological functions of the studied proteins. The results of DFT calculations also showed that the studied complexes exhibited good stability and are suitable candidates for the development of anticancer agents.

Nanomaterials: Breaking through the bottleneck of tumor immunotherapy

Immunotherapy exerts its excellent anti-tumor effects by stimulating and enhancing the immune response of the body, and has become another important class of anti-tumor therapy besides chemotherapy, targeted therapy and radiotherapy. Various types of immunotherapeutic drugs have gained their clinical values, but the in vivo delivery of drugs still faces many challenges, such as poor tumor permeability and low tumor cell uptake rate. In recent years, owing to highly targeting properties, better biocompatibility, and easy functionalization, nanomaterials have been widely applicated in tumor treatment, especially in tumor immunotherapy. Furthermore, nanomaterials have large drug loading capacity, strong tumor targeting and easy modification, which can effectively overcome the drawbacks of traditional immunotherapy. This paper reviews the progress of nanomaterial-based tumor immunotherapy in recent years and provides a theoretical basis for exploring new nanomaterial-based tumor immunotherapy strategies.

Furo[2,3-d]pyrimidines as Mackinazolinone/Isaindigotone Analogs: Synthesis, Modification, Antitumor Activity, and Molecular Docking Study

The chemical transformation of the tricyclic furo[2,3-d]pyrimidines was performed under isosteric and scaffold-hopping strategies focusing on the synthesis of its arylidene and imine-containing derivatives. Naturally-occurring alkaloids mackinazolinone and isaindigotone were as templates of target heterocycles. Synthesized compounds evaluated for their antitumor activity on human cancer cervical HeLa, breast MCF-7, and colon HT-29 cell lines. Four compounds: 8c, 8e, 10b, and 10c demonstrated potency against HeLa and HT-29 cell lines, and IC₅₀ values were between 7.37-13.72 μM, respectively. The molecular docking results showed that compounds 8c and 10b had good binding and high matching with the target EGFR protein.

Enhancing Skin Cancer Immunotheranostics and Precision Medicine through Functionalized Nanomodulators and Nanosensors: Recent Development and Prospects

Skin cancers, especially melanomas, present a formidable diagnostic and therapeutic challenge to the scientific community. Currently, the incidence of melanomas shows a high increase worldwide. Traditional therapeutics are limited to stalling or reversing malignant proliferation, increased metastasis, or rapid recurrence. Nonetheless, the advent of immunotherapy has led to a paradigm shift in treating skin cancers. Many state-of-art immunotherapeutic techniques, namely, active vaccination, chimeric antigen receptors, adoptive T-cell transfer, and immune checkpoint blockers, have achieved a considerable increase in survival rates. Despite its promising outcomes, current immunotherapy is still limited in its efficacy. Newer modalities are now being explored, and significant progress is made by integrating cancer immunotherapy with modular nanotechnology platforms to enhance its therapeutic efficacy and diagnostics. Research on targeting skin cancers with nanomaterial-based techniques has been much more recent than other cancers. Current investigations using nanomaterial-mediated targeting of nonmelanoma and melanoma cancers are directed at augmenting drug delivery and immunomodulation of skin cancers to induce a robust anticancer response and minimize toxic effects. Many novel nanomaterial formulations are being discovered, and clinical trials are underway to explore their efficacy in targeting skin cancers through functionalization or drug encapsulation. The focus of this review rivets on theranostic nanomaterials that can modulate immune mechanisms toward protective, therapeutic, or diagnostic approaches for skin cancers. The recent breakthroughs in nanomaterial-based immunotherapeutic modulation of skin cancer types and diagnostic potentials in personalized immunotherapies are discussed.

Recent advances in flavonoid-based nanocarriers as an emerging drug delivery approach for cancer chemotherapy

Flavonoids are an interesting class of biomolecules, which exhibit cancer-inhibitory effects through both chemopreventive and chemotherapeutic activities. However, their therapeutic efficacy is affected by poor pharmacokinetics (PK) and biopharmaceutical attributes. One of the most promising approaches to resolve these issues is to formulate flavonoids in nanosystems. Different flavonoid nanoformulations have shown therapeutic superiority over free flavonoids. Functionalization of nanoparticles (NPs) further improves their therapeutic efficacy by facilitating site-specific delivery and reducing nonspecific toxicities. In this review, we highlight recent developments in the field of flavonoid-based NPs to gain translational insights into the potential applications of flavonoid-based nanocarriers in cancer management.