Tumor Microenvironment-Stimuli Responsive Nanoparticles for Anticancer Therapy

Nanoparticle-mediated metronomic chemotherapy in cancer: A paradigm of precision and persistence

Current methods of cancer therapy have demonstrated enormous potential in tumor inhibition. However, a high dosage regimen of chemotherapy results in various complications which affect the normal body cells. Tumor cells also develop resistance against the prescribed drugs in the whole treatment regimen increasing the risk of cancer relapse. Metronomic chemotherapy is a modern treatment method that involves administering drugs at low doses continuously, allowing the drug sufficient time to take its effect. This method ensures that the toxicity of the drugs is to a minimum in comparison to conventional chemotherapy. Nanoparticles have shown efficacy in delivering drugs to the tumor cells in various cancer therapies. Combining nanoparticles with metronomic chemotherapy can yield better treatment results. This combination stimulates the immune system, improving cancer cells recognition by immune cells. Evidence from clinical and pre-clinical trials supports the use of metronomic delivery for drug-loaded nanoparticles. This review focuses on the functionalization of nanoparticles for improved drug delivery and inhibition of tumor growth. It emphasizes the mechanisms of metronomic chemotherapy and its conjunction with nanotechnology. Additionally, it explores tumor progression and the current methods of chemotherapy. The challenges associated with nano-based metronomic chemotherapy are outlined, paving the way for prospects in this dynamic field.

Targeting macrophages with multifunctional nanoparticles to detect and prevent atherosclerotic cardiovascular disease

Despite the emergence of novel diagnostic, pharmacological, interventional, and prevention strategies, atherosclerotic cardiovascular disease remains a significant cause of morbidity and mortality. Nanoparticle (NP)-based platforms encompass diverse imaging, delivery, and pharmacological properties that provide novel opportunities for refining diagnostic and therapeutic interventions for atherosclerosis at the cellular and molecular levels. Macrophages play a critical role in atherosclerosis and therefore represent an important disease-related diagnostic and therapeutic target, especially given their inherent ability for passive and active NP uptake. In this review, we discuss an array of inorganic, carbon-based, and lipid-based NPs that provide magnetic, radiographic, and fluorescent imaging capabilities for a range of highly promising research and clinical applications in atherosclerosis. We discuss the design of NPs that target a range of macrophage-related functions such as lipoprotein oxidation, cholesterol efflux, vascular inflammation, and defective efferocytosis. We also provide examples of NP systems that were developed for other pathologies such as cancer and highlight their potential for repurposing in cardiovascular disease. Finally, we discuss the current state of play and the future of theranostic NPs. Whilst this is not without its challenges, the array of multifunctional capabilities that are possible in NP design ensures they will be part of the next frontier of exciting new therapies that simultaneously improve the accuracy of plaque diagnosis and more effectively reduce atherosclerosis with limited side effects.

In vitro biological evaluation of a novel folic acid-targeted receptor quantum dot-β-cyclodextrin carrier for C-2028 unsymmetrical bisacridine in the treatment of human lung and prostate cancers

BACKGROUND

Traditional small-molecule chemotherapeutics usually do not distinguish tumors from healthy tissues. However, nanotechnology creates nanocarriers that selectively deliver drugs to their site of action. This work is the next step in the development of the quantum dot-β-cyclodextrin-folic acid (QD-β-CD-FA) platform for targeted and selected delivery of C-2028 unsymmetrical bisacridine in cancer therapy.

METHODS

Herein, we report an initial biological evaluation (using flow cytometry and light microscopy) as well as cell migration analysis of QD-β-CD(C-2028)-FA nanoconjugate and its components in the selected human lung and prostate cancer cells, as well as against their respective normal cells.

RESULTS

C-2028 compound induced apoptosis, which was much stronger in cancer cells compared to normal cells. Conjugation of C-2028 with QDgreen increased cellular senescence, while the introduction of FA to the conjugate significantly decreased this process. C-2028 nanoencapsulation also reduced cell migration. Importantly, QDgreen and QDgreen-β-CD-FA themselves did not induce any toxic responses in studied cells.

CONCLUSIONS

In conclusion, the results demonstrate the high potential of a novel folic acid-targeted receptor quantum dot-β-cyclodextrin carrier (QDgreen-β-CD-FA) for drug delivery in cancer treatment. Nanoplatforms increased the amount of delivered compounds and demonstrated high suitability.

A novel nanoformulation of parthenolide coated with polydopamine shows selective cytotoxicity and induces apoptosis in gastric cancer cells

An anticancer agent derived from a natural product, parthenolide (PN), was studied to formulate PN into poly(lactic-co-glycolic acid) (PLGA). Polydopamine (PDA) was employed to modify the surface of PN-PLGA. Following characterization, the PN-PLGA-PDA was evaluated for its in vitro release, cytotoxicity, and ability to induce apoptosis using flow cytometry and real-time quantitative PCR. According to the present study, PN-PLGA-PDA had a size of 195.5 nm which is acceptable for efficient enhanced permeation and retention (EPR) performance. The SEM results confirmed the size and spherical shape of the nanoparticles. The percentage of encapsulation efficiency was 96.9%. The zeta potential of PN-PLGA-PDA was - 31.8 mV which was suitable for its stability. FTIR spectra of the PN-PLGA-PDA indicated the chemical stability of the PN due to intermolecular hydrogen bonds between polymer and drug. The release of PN from PN-PLGA-PDA in PBS (pH 7.4) was only 20% during the first 48 h and less than 40% during 144 h. PN-PLGA-PDA exhibited anticancer properties in a dose-dependent manner that was more cytotoxic against cancer cells than normal cells. Moreover, real-time qPCR results indicated that the formulation activated apoptosis genes to exert its cytotoxic effect and activate the NF-kB pathway. Based on our findings, PN-PLGA-PDA could serve as a potential treatment for cancer.

Study of the anti-cancer activity of a mesoporous silica nanoparticle surface coated with polydopamine loaded with umbelliprenin

A mesoporous silica nanoparticle (MSN) coated with polydopamine (PDA) and loaded with umbelliprenin (UMB) was prepared and evaluated for its anti-cancer properties in this study. Then UMB-MSN-PDA was characterized by dynamic light scattering (DLS), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM) and FTIR methods. UV-visible spectrometry was employed to study the percentage of encapsulation efficiency (EE%). UMB-MSN-PDA mediated cell cytotoxicity and their ability to induce programmed cell death were evaluated by MTT, real-time qPCR, flow cytometry, and AO/PI double staining methods. The size of UMB-MSN-PDA was 196.7 with a size distribution of 0.21 and a surface charge of -41.07 mV. The EE% was 91.92%. FESEM and TEM showed the spherical morphology of the UMB-MSN-PDA. FTIR also indicated the successful interaction of the UMB and MSN and PDA coating. The release study showed an initial 20% release during the first 24 h of the study and less than 40% during 168 h. The lower cytotoxicity of the UMB-MSN-PDA against HFF normal cells compared to MCF-7 carcinoma cells suggested the safety of formulation on normal cells and tissues. The induction of apoptosis in MCF-7 cells was indicated by the upregulation of P53, caspase 8, and caspase 9 genes, enhanced Sub-G1 phase cells, and the AO/PI fluorescent staining. As a result of these studies, it may be feasible to conduct preclinical studies shortly to evaluate the formulation for its potential use in cancer treatment.

Nano-Engineering Strategies for Tumor-Specific Therapy

Nanodelivery systems (NDSs) provide promising prospects for decreasing drug doses, reducing side effects, and improving therapeutic effects. However, the bioapplications of NDSs are still compromised by their fast clearance, indiscriminate biodistribution, and limited tumor accumulation. Hence, engineering modification of NDSs aiming at promoting tumor-specific therapy and avoiding systemic toxicity is usually needed. An NDS integrating various functionalities, including flexible camouflage, specific biorecognition, and sensitive stimuli-responsiveness, into one sequence would be "smart" and highly effective. Herein, we systematically summarize the related principles, methods, and progress. At the end of the review, we predict the obstacles to precise nanoengineering and prospects for the future application of NDSs.

Biopolymer-based tumor microenvironment-responsive nanomedicine for targeted cancer therapy

Nanomedicine has opened up new avenues for cancer treatment by enhancing drug solubility, permeability and targeted delivery to cancer cells. Despite its numerous advantages over conventional therapies, nanomedicine may exhibit off-target drug distribution, harming nontarget regions. The increased permeation and retention effect of nanomedicine in tumor sites also has its limitations, as abnormal tumor vasculature, dense stroma structure and altered tumor microenvironment (TME) may result in limited intratumor distribution and therapeutic failure. However, TME-responsive nanomedicine has exhibited immense potential for efficient, safe and precise delivery of therapeutics utilizing stimuli specific to the TME. This review discusses the mechanistic aspects of various TME-responsive biopolymers and their application in developing various types of TME-responsive nanomedicine.

Theranostic applications of peptide-based nanoformulations for growth factor defective cancers

Growth factors play a pivotal role in orchestrating cellular growth and division by binding to specific cell surface receptors. Dysregulation of growth factor production or activity can contribute to the uncontrolled cell proliferation observed in cancer. Peptide-based nanoformulations (PNFs) have emerged as promising therapeutic strategies for growth factor-deficient cancers. PNFs offer multifaceted capabilities including targeted delivery, imaging modalities, combination therapies, resistance modulation, and personalized medicine approaches. Nevertheless, several challenges remain, including limited specificity, stability, pharmacokinetics, tissue penetration, toxicity, and immunogenicity. To address these challenges and optimize PNFs for clinical translation, in-depth investigations are warranted. Future research should focus on elucidating the intricate interplay between peptides and nanoparticles, developing robust spectroscopic and computational methodologies, and establishing a comprehensive understanding of the structure-activity relationship governing peptide-nanoparticle interactions. Bridging these knowledge gaps will propel the translation of peptide-nanoparticle therapies from bench to bedside. While a few peptide-nanoparticle drugs have obtained FDA approval for cancer treatment, the integration of nanostructured platforms with peptide-based medications holds tremendous potential to expedite the implementation of innovative anticancer interventions. Therefore, growth factor-deficient cancers present both challenges and opportunities for targeted therapeutic interventions, with peptide-based nanoformulations positioned as a promising avenue. Nonetheless, concerted research and development endeavors are essential to optimize the specificity, stability, and safety profiles of PNFs, thereby advancing the field of peptide-based nanotherapeutics in the realm of oncology research.

Nanoparticle drug delivery systems responsive to tumor microenvironment: Promising alternatives in the treatment of triple-negative breast cancer

The conventional therapeutic treatment of triple-negative breast cancer (TNBC) is negatively influenced by the development of tumor cell drug resistant, and systemic toxicity of therapeutic agents due to off-target activity. In accordance with research findings, nanoparticles (NPs) responsive to the tumor microenvironment (TME) have been discovered for providing opportunities to selectively target tumor cells via active targeting or Enhanced Permeability and Retention (EPR) effect. The combination of the TME control and therapeutic NPs offers promising solutions for improving the prognosis of the TNBC because the TME actively participates in tumor growth, metastasis, and drug resistance. The NP-based systems leverage stimulus-responsive mechanisms, such as low pH value, hypoxic, excessive secretion enzyme, concentration of glutathione (GSH)/reactive oxygen species (ROS), and high concentration of Adenosine triphosphate (ATP) to combat TNBC progression. Concurrently, NP-based stimulus-responsive introduces a novel approach for drug dosage design, administration, and modification of the pharmacokinetics of conventional chemotherapy and immunotherapy drugs. This review provides a comprehensive examination of the strengths, limitations, applications, perspectives, and future expectations of both novel and traditional stimulus-responsive NP-based drug delivery systems for improving outcomes in the medical practice of TNBC. This article is categorized under: Therapeutic Approaches and Drug Discovery > Emerging Technologies Nanotechnology Approaches to Biology > Nanoscale Systems in Biology Therapeutic Approaches and Drug Discovery > Nanomedicine for Oncologic Disease.

Advances in Polymeric Micelles: Responsive and Targeting Approaches for Cancer Immunotherapy in the Tumor Microenvironment

In recent years, to treat a diverse array of cancer forms, considerable advancements have been achieved in the field of cancer immunotherapies. However, these therapies encounter multiple challenges in clinical practice, such as high immune-mediated toxicity, insufficient accumulation in cancer tissues, and undesired off-target reactions. To tackle these limitations and enhance bioavailability, polymer micelles present potential solutions by enabling precise drug delivery to the target site, thus amplifying the effectiveness of immunotherapy. This review article offers an extensive survey of recent progress in cancer immunotherapy strategies utilizing micelles. These strategies include responsive and remodeling approaches to the tumor microenvironment (TME), modulation of immunosuppressive cells within the TME, enhancement of immune checkpoint inhibitors, utilization of cancer vaccine platforms, modulation of antigen presentation, manipulation of engineered T cells, and targeting other components of the TME. Subsequently, we delve into the present state and constraints linked to the clinical utilization of polymeric micelles. Collectively, polymer micelles demonstrate excellent prospects in tumor immunotherapy by effectively addressing the challenges associated with conventional cancer immunotherapies.

Progress in the treatment of drug-loaded nanomaterials in renal cell carcinoma

Renal cell carcinoma (RCC) is a common urinary tract tumor that arises from the highly heterogeneous epithelium of the renal tubules. The incidence of kidney cancer is second only to the incidence of bladder cancer, and has shown an upward trend over time. Although surgery is the preferred treatment for localized RCC, treatment decisions should be customized to individual patients considering their overall health status and the risk of developing or worsening chronic kidney disease postoperatively. Anticancer drugs are preferred to prevent perioperative and long-term postoperative complications; however, resistance to chemotherapy remains a considerable problem during the treatment process. To overcome this challenge, nanocarriers have emerged as a promising strategy for targeted drug delivery for cancer treatment. Nanocarriers can transport anticancer agents, achieving several-fold higher cytotoxic concentrations in tumors and minimizing toxicity to the remaining parts of the body. This article reviews the use of nanomaterials, such as liposomes, polymeric nanoparticles, nanocomposites, carbon nanomaterials, nanobubbles, nanomicelles, and mesoporous silica nanoparticles, for RCC treatment, and discusses their advantages and disadvantages.

Biomaterials-enhanced bioactive agents to efficiently block spinal metastases of cancers

The spine is the most common site of bone metastases, as 20%-40% of cancer patients suffer from spinal metastases. Treatments for spinal metastases are scarce and palliative, primarily aiming at relieving bone pain and preserving neurological function. The bioactive agents-mediated therapies are the most effective modalities for treating spinal metastases because they achieve systematic and specific tumor regression. However, the clinical applications of some bioactive agents are limited due to the lack of targeting capabilities, severe side effects, and vulnerability of drug resistance. Fortunately, advanced biomaterials have been developed as excipients to enhance these treatments, including chemotherapy, phototherapy, magnetic hyperthermia therapy, and combination therapy, by improving tumor targeting and enabling sustaining and stimuli-responsive release of various therapeutic agents. Herein, the review summarizes the development of biomaterials-mediated bioactive agents for enhanced treatments of spinal metastases and predicts future research trends.

Cascade strategy for glucose oxidase-based synergistic cancer therapy using nanomaterials

Nanomaterial-based cancer therapy faces significant limitations due to the complex nature of the tumor microenvironment (TME). Starvation therapy is an emerging therapeutic approach that targets tumor cell metabolism using glucose oxidase (GOx). Importantly, it can provide a material or environmental foundation for other diverse therapeutic methods by manipulating the properties of the TME, such as acidity, hydrogen peroxide (H2O2) levels, and hypoxia degree. In recent years, this cascade strategy has been extensively applied in nanoplatforms for ongoing synergetic therapy and still holds undeniable potential. However, only a few review articles comprehensively elucidate the rational designs of nanoplatforms for synergetic therapeutic regimens revolving around the conception of the cascade strategy. Therefore, this review focuses on innovative cascade strategies for GOx-based synergetic therapy from representative paradigms to state-of-the-art reports to provide an instructive, comprehensive, and insightful reference for readers. Thereafter, we discuss the remaining challenges and offer a critical perspective on the further advancement of GOx-facilitated cancer treatment toward clinical translation.

Lipid polymer hybrid nanoparticles: a custom-tailored next-generation approach for cancer therapeutics

Lipid-based polymeric nanoparticles are the highly popular carrier systems for cancer drug therapy. But presently, detailed investigations have revealed their flaws as drug delivery carriers. Lipid polymer hybrid nanoparticles (LPHNPs) are advanced core-shell nanoconstructs with a polymeric core region enclosed by a lipidic layer, presumed to be derived from both liposomes and polymeric nanounits. This unique concept is of utmost importance as a combinable drug delivery platform in oncology due to its dual structured character. To add advantage and restrict one's limitation by other, LPHNPs have been designed so to gain number of advantages such as stability, high loading of cargo, increased biocompatibility, rate-limiting controlled release, and elevated drug half-lives as well as therapeutic effectiveness while minimizing their drawbacks. The outer shell, in particular, can be functionalized in a variety of ways with stimuli-responsive moieties and ligands to provide intelligent holding and for active targeting of antineoplastic medicines, transport of genes, and theragnostic. This review comprehensively provides insight into recent substantial advancements in developing strategies for treating various cancer using LPHNPs. The bioactivity assessment factors have also been highlighted with a discussion of LPHNPs future clinical prospects.

Microenvironment Restruction of Emerging 2D Materials and their Roles in Therapeutic and Diagnostic Nano-Bio-Platforms

Engineering advanced therapeutic and diagnostic nano-bio-platforms (NBPFs) have emerged as rapidly-developed pathways against a wide range of challenges in antitumor, antipathogen, tissue regeneration, bioimaging, and biosensing applications. Emerged 2D materials have attracted extensive scientific interest as fundamental building blocks or nanostructures among material scientists, chemists, biologists, and doctors due to their advantageous physicochemical and biological properties. This timely review provides a comprehensive summary of creating advanced NBPFs via emerging 2D materials (2D-NBPFs) with unique insights into the corresponding molecularly restructured microenvironments and biofunctionalities. First, it is focused on an up-to-date overview of the synthetic strategies for designing 2D-NBPFs with a cross-comparison of their advantages and disadvantages. After that, the recent key achievements are summarized in tuning the biofunctionalities of 2D-NBPFs via molecularly programmed microenvironments, including physiological stability, biocompatibility, bio-adhesiveness, specific binding to pathogens, broad-spectrum pathogen inhibitors, stimuli-responsive systems, and enzyme-mimetics. Moreover, the representative therapeutic and diagnostic applications of 2D-NBPFs are also discussed with detailed disclosure of their critical design principles and parameters. Finally, current challenges and future research directions are also discussed. Overall, this review will provide cutting-edge and multidisciplinary guidance for accelerating future developments and therapeutic/diagnostic applications of 2D-NBPFs.

Doxorubicin-Loaded Fungal-Carboxymethyl Chitosan Functionalized Polydopamine Nanoparticles for Photothermal Cancer Therapy

In this work, we synthesized doxorubicin-loaded fungal-carboxymethyl chitosan (FC) functionalized polydopamine (Dox@FCPDA) nanoparticles for improved anticancer activity via photothermal drug release. The photothermal properties revealed that the FCPDA nanoparticles with a concentration of 400 µg/mL produced a temperature of about 61.1 °C at 2 W/cm² laser illumination, which is more beneficial for cancer cells. Due to the hydrophilic FC biopolymer, the Dox was successfully encapsulated into FCPDA nanoparticles via electrostatic interactions and pi-pi stacking. The maximum drug loading and encapsulation efficiency were calculated to be 19.3% and 80.2%, respectively. The Dox@FCPDA nanoparticles exhibited improved anticancer activity on HePG2 cancer cells when exposed to an NIR laser (800 nm, 2 W/cm²). Furthermore, the Dox@FCPDA nanoparticles also improved cellular uptake with HepG2 cells. Therefore, functionalizing FC biopolymer with PDA nanoparticles is more beneficial for drug and photothermal dual therapeutic properties for cancer therapy.

A paclitaxel prodrug nanoparticles with glutathion/reactive oxygen species dual-responsive and CD206 targeting to improve the anti-tumour effect

As a first-line anticancer drug, paclitaxel has shortcomings, such as poor solubility and lack of tumour cell selectivity, which limit its further applications in clinical practice. Therefore, the authors aimed to utilise the characteristics of prodrug and nanotechnology to prepare a reactive oxygen species (ROS) and GSH dual-responsive targeted tumour prodrug nanoparticle Man-PEG-SS-PLGA/ProPTX to improve the clinical application status of paclitaxel limitation. The characterisation of Man-PEG-SS-PLGA/ProPTX was carried out through preparation. The cytotoxicity of nanoparticles on tumour cells and the effect on apoptosis of tumour cells were investigated by cytotoxicity assay and flow cytometry analysis. The ROS responsiveness of nanoparticles was investigated by detecting the ROS level of tumour cells. The tumour cell selectivity of the nanoparticles was further investigated by receptor affinity assay and cell uptake assay. The particle size of Man-PEG-SS-PLGA/ProPTX was (132.90 ± 1.81) nm, the dispersion coefficient Polymer dispersity index was 0.13 ± 0.03, and the Zeta potential was (-8.65 ± 0.50) mV. The encapsulation rate was 95.46 ± 2.31% and the drug load was 13.65 ± 2.31%. The nanoparticles could significantly inhibit the proliferation and promote apoptosis of MCF-7, HepG2, and MDA-MB-231 tumour cells. It has good ROS response characteristics and targeting. The targeted uptake mechanism is energy-dependent and endocytosis is mediated by non-clathrin, non-caveolin, lipid raft/caveolin, and cyclooxygenase (COX)/caveolin with a certain concentration dependence and time dependence. Man-PEG-SS-PLGA/ProPTX is a tumour microenvironment-responsive nanoparticle that can actively target tumour cells. It restricts the release of PTX in normal tissues, enhances its selectivity to tumour cells, and has significant antitumour activity, which is expected to solve the current limitations of PTX use.

Tumor microenvironment stimuli-responsive lipid-drug conjugates for cancer treatment

Lipid drug conjugates (LDCs) have attracted considerable attention in the fields of drug delivery and pharmacology due to their ability to target specific cells, increase drug solubility, reduce toxicity, and improve therapeutic efficacy. These unique features make LDCs promising candidates for the treatment cancer, inflammation, and infectious diseases. In fact, by choosing specific linkers between the lipid and drug molecules, stimuli-responsive LDCs can be designed to target cancer cells based on the unique properties of the tumor microenvironment. Despite the fact that many reviews have described LDCs, few articles have focused on tumor microenvironmental stimuli-responsive LDCs for cancer treatment. Therefore, the key elements of these types of LDCs in cancer treatment will be outlined and discussed in this paper. Our paper goes into detail on the concepts and benefits of LDCs, the various types of tumor microenvironment stimuli-responsive LDCs (such as pH, redox, enzyme, or reactive oxygen species-responsive LDCs), and the current status of LDCs in clinical trials.

Intracellular Glucose-Depriving Polymer Micelles for Antiglycolytic Cancer Treatment

A new anticancer strategy to exploit abnormal metabolism of cancer cells rather than to merely control the drug release or rearrange the tumor microenvironment is reported. An antiglycolytic amphiphilic polymer, designed considering the unique metabolism of cancer cells (Warburg effect) and aimed at the regulation of glucose metabolism, is synthesized through chemical conjugation between glycol chitosan (GC) and phenylboronic acid (PBA). GC-PBA derivatives form stable micellar structures under physiological conditions and respond to changes in glucose concentration. Once the micelles accumulate at the tumor site, intracellular glucose capture occurs, and the resultant energy deprivation through the inhibition of aerobic glycolysis remarkably suppresses tumor growth without significant side effects in vivo. This strategy highlights the need to develop safe and effective cancer treatment without the use of conventional anticancer drugs.

An Overview on Gold Nanorods as Versatile Nanoparticles in Cancer Therapy

Gold nanorods (GNRs/AuNRs) are a group of gold nanoparticles which their simple surface chemistry allows for various surface modifications, providing the possibility of using them in the fabrication of biocompatible and functional nano-agents for cancer therapy. AuNRs, moreover, exhibit a maximum absorption of longitudinal localized surface plasmon resonance (LSPR) in the near-infrared (NIR) region which overlaps with NIR bio-tissue 'window' suggesting that they are proper tools for thermal ablation of cancer cells. AuNRs can be used for induction of mono or combination therapies by administering various therapeutic approaches such as photothermal therapy (PTT), photodynamic therapy (PDT), chemotherapy (CT), radiotherapy (RT), and gene therapy (GT). In this review, anticancer therapeutic capacities of AuNRs along with different surface modifications are summarized comprehensively. The roles of AuNRs in fabrication of various nano-constructs are also discussed.

Nanotechnology-augmented sonodynamic therapy and associated immune-mediated effects for the treatment of pancreatic ductal adenocarcinoma

PURPOSE

Sonodynamic therapy (SDT) is emerging as a cancer treatment alternative with significant advantages over conventional therapies, including its minimally invasive and site-specific nature, its radical antitumour efficacy with minimal side effects, and its capacity to raise an antitumour immune response. The study explores the efficacy of SDT in combination with nanotechnology against pancreatic ductal adenocarcinoma.

METHODS

A nanoparticulate formulation (HPNP) based on a cathepsin B-degradable glutamate-tyrosine co-polymer that carries hematoporphyrin was used in this study for the SDT-based treatment of PDAC. Cathepsin B levels in BxPC-3 and PANC-1 cells were correlated to cellular uptake of HPNP. The HPNP efficiency to induce a sonodynamic effect at varying ultrasound parameters, and at different oxygenation and pH conditions, was investigated. The biodistribution, tumour accumulation profile, and antitumour efficacy of HPNP in SDT were examined in immunocompetent mice carrying bilateral ectopic murine pancreatic tumours. The immune response profile of excised tumour tissues was also examined.

RESULTS

The HPNP formulation significantly improved cellular uptake of hematoporphyrin for both BxPC-3 and PANC-1 cells, while increase of cellular uptake was positively correlated in PANC-1 cells. There was a clear SDT-induced cytotoxicity at the ultrasound conditions tested, and the treatment impaired the capacity of both BxPC-3 and PANC-1 cells to form colonies. The overall acoustic energy and pulse length, rather than the power density, were key in eliciting the effects observed in vitro. The SDT treatment in combination with HPNP resulted in 21% and 27% reduction of the target and off-target tumour volumes, respectively, within 24 h. A single SDT treatment elicited an antitumour effect that was characterized by an SDT-induced decrease in immunosuppressive T cell phenotypes.

CONCLUSION

SDT has significant potential to serve as a monotherapy or adjunctive treatment for inoperable or borderline resectable PDAC.

Cancer Stem Cells and the Tumor Microenvironment: Targeting the Critical Crosstalk through Nanocarrier Systems

The physiological state of the tumor microenvironment (TME) plays a central role in cancer development due to multiple universal features that transcend heterogeneity and niche specifications, like promoting cancer progression and metastasis. As a result of their preponderant involvement in tumor growth and maintenance through several microsystemic alterations, including hypoxia, oxidative stress, and acidosis, TMEs make for ideal targets in both diagnostic and therapeutic ventures. Correspondingly, methodologies to target TMEs have been investigated this past decade as stratagems of significant potential in the genre of focused cancer treatment. Within targeted oncotherapy, nanomedical derivates-nanocarriers (NCs) especially-have emerged to present notable prospects in enhancing targeting specificity. Yet, one major issue in the application of NCs in microenvironmental directed therapy is that TMEs are too broad a spectrum of targeting possibilities for these carriers to be effectively employed. However, cancer stem cells (CSCs) might portend a solution to the above conundrum: aside from being quite heavily invested in tumorigenesis and therapeutic resistance, CSCs also show self-renewal and fluid clonogenic properties that often define specific TME niches. Further scrutiny of the relationship between CSCs and TMEs also points towards mechanisms that underly tumoral characteristics of metastasis, malignancy, and even resistance. This review summarizes recent advances in NC-enabled targeting of CSCs for more holistic strikes against TMEs and discusses both the current challenges that hinder the clinical application of these strategies as well as the avenues that can further CSC-targeting initiatives. Central role of CSCs in regulation of cellular components within the TME.

A Label-Free Fluorescence Aptasensor Based on G-Quadruplex/Thioflavin T Complex for the Detection of Trypsin

A novel, label-free fluorescent assay has been developed for the detection of trypsin by using thioflavin T as a fluorescent probe. A specific DNA aptamer can be combined by adding cytochrome c. Trypsin hydrolyzes the cytochrome c into small peptide fragments, exposing the G-quadruplex part of DNA aptamer, which has a high affinity for thioflavin T, which then enhances the fluorescence intensity. In the absence of trypsin, the fluorescence intensity was inhibited as the combination of cytochrome c and the DNA aptamer impeded thioflavin T’s binding. Thus, the fluorescent biosensor showed a linear relationship from 0.2 to 60 μg/mL with a detection limit of 0.2 μg/mL. Furthermore, the proposed method was also successfully employed for determining trypsin in biological samples. This method is simple, rapid, cheap, and selective and possesses great potential for the detection of trypsin in bioanalytical and biological samples and medical diagnoses.

Fabrication of Polymersomes: A Macromolecular Architecture in Nanotherapeutics

In consideration of the issues of drug delivery systems, the artificial vesicle structures composed of block copolymers called polymersomes recently gained considerable attention. The possibility of tuning the mechanical parameter and increasing the scale-up production of polymersomes led to its wide application in healthcare. Bearing in mind the disease condition, the structure and properties of the polymersomes could be tuned to serve the purpose. Furthermore, specific ligands can be incorporated on the vesicular surface to induce smart polymersomes, thus improving targeted delivery. The synthesis method and surface functionalization are the two key aspects that determine the versatility of biological applications as they account for stability, specific targeting, degradability, biocompatibility, and bioavailability. A perfectly aligned polymer vesicle can mimic the cells/organelles and function by avoiding cytotoxicity. This supramolecular structure can carry and deliver payloads of a wide range, including drugs, proteins, and genes, contributing to the construction of next-generation therapeutics. These aspects promote the potential use of such components as a framework to approach damaged tissue while maintaining healthy environments during circulation. Herein, this article concentrates specifically on the drug delivery applications of polymersomes.

Recent advances in smart nanoplatforms for tumor non-interventional embolization therapy

Tumor embolization therapy has attracted great attention due to its high efficiency in inhibiting tumor growth by cutting off tumor nutrition and oxygen supply by the embolic agent. Although transcatheter arterial embolization (TAE) is the mainstream technique in the clinic, there are still some limitations to be considered, especially the existence of high risks and complications. Recently, nanomaterials have drawn wide attention in disease diagnosis, drug delivery, and new types of therapies, such as photothermal therapy and photodynamic therapy, owing to their unique optical, thermal, convertible and in vivo transport properties. Furthermore, the utilization of nanoplatforms in tumor non-interventional embolization therapy has attracted the attention of researchers. Herein, the recent advances in this area are summarized in this review, which revealed three different types of nanoparticle strategies: (1) nanoparticles with active targeting effects or stimuli responsiveness (ultrasound and photothermal) for the safe delivery and responsive release of thrombin; (2) tumor microenvironment (copper and phosphate, acidity and GSH/H₂O₂)-responsive nanoparticles for embolization therapy with high specificity; and (3) peptide-based nanoparticles with mimic functions and excellent biocompatibility for tumor embolization therapy. The benefits and limitations of each kind of nanoparticle in tumor non-interventional embolization therapy will be highlighted. Investigations of nanoplatforms are undoubtedly of great significance, and some advanced nanoplatform systems have arrived at a new height and show potential applications in practical applications.

Gold Nanoparticles Contact with Cancer Cell: A Brief Update

The fine-tuning of the physicochemical properties of gold nanoparticles has facilitated the rapid development of multifunctional gold-based nanomaterials with diagnostic, therapeutic, and therapeutic applications. Work on gold nanoparticles is increasingly focusing on their cancer application. This review provides a summary of the main biological effects exerted by gold nanoparticles on cancer cells and highlights some critical factors involved in the interaction process (protein corona, tumor microenvironment, surface functionalization). The review also contains a brief discussion of the application of gold nanoparticles in target discovery.

Recent Progress in Bio-Responsive Drug Delivery Systems for Tumor Therapy

Spatially- and/or temporally-controlled drug release has always been the pursuit of drug delivery systems (DDSs) to achieve the ideal therapeutic effect. The abnormal pathophysiological characteristics of the tumor microenvironment, including acidosis, overexpression of special enzymes, hypoxia, and high levels of ROS, GSH, and ATP, offer the possibility for the design of stimulus-responsive DDSs for controlled drug release to realize more efficient drug delivery and anti-tumor activity. With the help of these stimulus signals, responsive DDSs can realize controlled drug release more precisely within the local tumor site and decrease the injected dose and systemic toxicity. This review first describes the major pathophysiological characteristics of the tumor microenvironment, and highlights the recent cutting-edge advances in DDSs responding to the tumor pathophysiological environment for cancer therapy. Finally, the challenges and future directions of bio-responsive DDSs are discussed.

Smart nanomaterials for cancer diagnosis and treatment

Innovations in nanomedicine has guided the improved outcomes for cancer diagnosis and therapy. However, frequent use of nanomaterials remains challenging due to specific limitations like non-targeted distribution causing low signal-to-noise ratio for diagnostics, complex fabrication, reduced-biocompatibility, decreased photostability, and systemic toxicity of nanomaterials within the body. Thus, better nanomaterial-systems with controlled physicochemical and biological properties, form the need of the hour. In this context, smart nanomaterials serve as promising solution, as they can be activated under specific exogenous or endogenous stimuli such as pH, temperature, enzymes, or a particular biological molecule. The properties of smart nanomaterials make them ideal candidates for various applications like biosensors, controlled drug release, and treatment of various diseases. Recently, smart nanomaterial-based cancer theranostic approaches have been developed, and they are displaying better selectivity and sensitivity with reduced side-effects in comparison to conventional methods. In cancer therapy, the smart nanomaterials-system only activates in response to tumor microenvironment (TME) and remains in deactivated state in normal cells, which further reduces the side-effects and systemic toxicities. Thus, the present review aims to describe the stimulus-based classification of smart nanomaterials, tumor microenvironment-responsive behaviour, and their up-to-date applications in cancer theranostics. Besides, present review addresses the development of various smart nanomaterials and their advantages for diagnosing and treating cancer. Here, we also discuss about the drug targeting and sustained drug release from nanocarriers, and different types of nanomaterials which have been engineered for this intent. Additionally, the present challenges and prospects of nanomaterials in effective cancer diagnosis and therapeutics have been discussed.

Smart pH-responsive nanomedicines for disease therapy

Background

Currently nanomedicines are the focus of attention from researchers and clinicians because of the successes of lipid-nanoparticles-based COVID-19 vaccines. Nanoparticles improve existing treatments by providing a number of advantages including protection of cargo molecules from external stresses, delivery of drugs to target tissues, and sustained drug release. To prevent premature release-related side effects, stable drug loading in nanoformulations is required, but the increased stability of the formulation could also lead to a poor drug-release profile at the target sites. Thus, researchers have exploited differences in a range of properties (e.g., enzyme levels, pH, levels of reduced glutathione, and reactive oxygen species) between non-target and target sites for site-specific release of drugs. Among these environmental stimuli, pH gradients have been widely used to design novel, responsive nanoparticles.

Area covered

In this review, we assess drug delivery based on pH-responsive nanoparticles at the levels of tissues (tumor microenvironment, pH ~ 6.5) and of intracellular compartments (endosome and lysosome, pH 4.5-6.5). Upon exposure to these pH stimuli, pH-responsive nanoparticles respond with physicochemical changes to their material structure and surface characteristics. These changes include swelling, dissociation, or surface charge switching, in a manner that favors drug release at the target site (the tumor microenvironment region and the cytosol followed by endosomal escape) rather than the surrounding tissues.

Expert opinion

Lastly, we consider the challenges involved in the development of pH-responsive nanomedicines.

Melanin and Melanin-Functionalized Nanoparticles as Promising Tools in Cancer Research-A Review

Cancer poses an ongoing global challenge, despite the substantial progress made in the prevention, diagnosis, and treatment of the disease. The existing therapeutic methods remain limited by undesirable outcomes such as systemic toxicity and lack of specificity or long-term efficacy, although innovative alternatives are being continuously investigated. By offering a means for the targeted delivery of therapeutics, nanotechnology (NT) has emerged as a state-of-the-art solution for augmenting the efficiency of currently available cancer therapies while combating their drawbacks. Melanin, a polymeric pigment of natural origin that is widely spread among many living organisms, became a promising candidate for NT-based cancer treatment owing to its unique physicochemical properties (e.g., high biocompatibility, redox behavior, light absorption, chelating ability) and innate antioxidant, photoprotective, anti-inflammatory, and antitumor effects. The latest research on melanin and melanin-like nanoparticles has extended considerably on many fronts, allowing not only efficient cancer treatments via both traditional and modern methods, but also early disease detection and diagnosis. The current paper provides an updated insight into the applicability of melanin in cancer therapy as antitumor agent, molecular target, and delivery nanoplatform.

Research Progress on Gene Editing Based on Nano-Drug Delivery Vectors for Tumor Therapy

Malignant tumors pose a serious threat to human health and have high fatality rates. Conventional clinical anti-tumor treatment is mainly based on traditional surgery, chemotherapy, radiotherapy, and interventional therapy, and even though these treatment methods are constantly updated, a satisfactory efficacy is yet to be obtained. Therefore, research on novel cancer treatments is being actively pursued. We review the classification of gene therapies of malignant tumors and their advantages, as well as the development of gene editing techniques. We further reveal the nano-drug delivery carrier effect in improving the efficiency of gene editing. Finally, we summarize the progress in recent years of gene editing techniques based on nano-drug delivery carriers in the treatment of various malignant tumors, and analyze the prospects of the technique and its restricting factors.

Anticancer nanomedicines harnessing tumor microenvironmental components

INTRODUCTION

Small-molecular drugs are extensively used in cancer therapy, while they have issues of nonspecific distribution and consequent side effects. Nanomedicines that incorporate chemotherapeutic drugs have been developed to enhance the therapeutic efficacy of these drugs and reduce their side effects. One of the promising strategies is to prepare nanomedicines by harnessing the unique tumor microenvironment (TME).

AREAS COVERED

The TME contains numerous cell types that specifically express specific antibodies on the surface including tumor vascular endothelial cells, tumor-associated adipocytes, tumor-associated fibroblasts, tumor-associated immune cells and cancer stem cells. The physicochemical environment is characterized with a low pH, hypoxia, and a high redox potential resulting from tumor-specific metabolism. The intelligent nanomedicines can be categorized into two groups: the first group which is rapidly responsive to extracellular chemical/biological factors in the TME and the second one which actively and/or specifically targets cellular components in the TME.

EXPERT OPINION

In this paper, we review recent progress of nanomedicines by harnessing the TME and illustrate the principles and advantages of different strategies for designing nanomedicines, which are of great significance for exploring novel nanomedicines or translating current nanomedicines into clinical practice. We will discuss the challenges and prospects of preparing nanomedicines to utilize or alter the TME for achieving effective, safe anticancer treatment.

Emerging nanomedicines of paclitaxel for cancer treatment

Malignant tumor is still a leading threat to human health. Despite the rapid development of targeted therapeutic strategies, any treatment specifically acting on single target would inevitably suffer from tumor resistance, largely due to the genetic instability and variability of tumor cells. Thus, traditional therapies such as broad-spectrum chemotherapy would certainly occupy an important position in clinical cancer therapy. Nevertheless, most chemotherapeutic drugs have long been criticized for unsatisfactory therapeutic efficacy with severe off-target toxicity. Although several chemotherapeutic nanomedicines with improved therapeutic safety have been applied in clinics, the therapeutic outcomes still do not fulfill expectation. To address this challenge, enormous efforts have been devoted to developing novel nano-formulations for efficient delivery of chemotherapeutic drugs. Herein, we aim to outline the latest progression in the emerging nanomedicines of paclitaxel (PTX), with special attention to the functional nanocarriers, self-delivering prodrug-nanoassemblies and combination nanotherapeutics of PTX. Finally, the challenges and opportunities of these functional PTX nanomedicines in clinical translation are spotlighted.

Poly (β amino esters) copolymers: Novel potential vectors for delivery of genes and related therapeutics

The unique properties of polymers have performed an essential contribution to the drug delivery system by providing an outstanding platform for the delivery of macromolecules and genes. However, the block copolymers have been the subject of many recently published works whose results have demonstrated excellent performance in drug targeting. Poly(β-amino esters) (PβAEs) copolymers are the synthetic cationic polymers that are tailored by chemically joining PβAEs with other additives to demonstrate extraordinary efficiency in designing pre-defined and pre-programmed nanostructures, site-specific delivery, andovercoming the distinct cellular barriers. Different compositional and structural libraries could be generated by combinatorial chemistry and by the addition of various novel functional additives that fulfill the multiple requirements of targeted delivery. These intriguing attributes allow PβAE-copolymers to have customized therapeutic functions such as excellent encapsulation capacity, high stability, and stimuli-responsive release. Here, we give an overview of PβAE copolymers-based formulations along with focusing on most notable improvements such as structural modifications, bio-conjugations, and stimuli-responsive approaches, for safe and effective nucleic acids delivery.

Enhanced Anticancer Efficacy of Chemotherapy by Amphiphilic Y-Shaped Polypeptide Micelles

Although the treatment modalities of cancers are developing rapidly, chemotherapy is still the primary treatment strategy for most solid cancers. The progress in nanotechnology provides an opportunity to upregulate the tumor suppression efficacy and decreases the systemic toxicities. As a promising nanoplatform, the polymer micelles are fascinating nanocarriers for the encapsulation and delivery of chemotherapeutic agents. The chemical and physical properties of amphiphilic co-polymers could significantly regulate the performances of the micellar self-assembly and affect the behaviors of controlled release of drugs. Herein, two amphiphilic Y-shaped polypeptides are prepared by the ring-opening polymerization of cyclic monomer l-leucine N-carboxyanhydride (l-Leu NCA) initiated by a dual-amino-ended macroinitiator poly(ethylene glycol) [mPEG-(NH2)2]. The block co-polypeptides with PLeu8 and PLeu16 segments could form spontaneously into micelles in an aqueous solution with hydrodynamic radii of 80.0 ± 6.0 and 69.1 ± 4.8 nm, respectively. The developed doxorubicin (DOX)-loaded micelles could release the payload in a sustained pattern and inhibit the growth of xenografted human HepG2 hepatocellular carcinoma with decreased systemic toxicity. The results demonstrated the great potential of polypeptide micellar formulations in cancer therapy clinically.

Leveraging disulfiram to treat cancer: Mechanisms of action, delivery strategies, and treatment regimens

Disulfiram (DSF) has been used as an alcoholism drug for 70 years. Recently, it has attracted increasing attention owing to the distinguished anticancer activity, which can be further potentiated by the supplementation of Cu²⁺. Although encouraging anticancer results are obtained in lab, the clinical outcomes of oral DSF are not satisfactory, which urges an in-depth understanding of the underlying mechanisms, bottlenecks, and proposal of potential methods to address the dilemma. In this review, a critical summarization of various molecular biological anticancer mechanisms of DSF/Cu²⁺ is provided and the predicament of orally delivering DSF in clinical oncotherapy is explained by the metabolic barriers. We highlight the recent advances in the DSF/Cu²⁺ delivery strategies and the emerging treatment regimens for cancer treatment. Last but not the least, we summarize the clinical trials regarding DSF and make a prospect of DSF/Cu-based cancer therapy.

Insights on functionalized carbon nanotubes for cancer theranostics

Despite the exciting breakthroughs in medical technology, cancer still accounts for one of the principle triggers of death and conventional therapeutic modalities often fail to attain an effective cure. Recently, nanobiotechnology has made huge advancement in cancer therapy with gigantic application potential because of their ability in achieving precise and controlled drug release, elevating drug solubility and reducing adverse effects. Carbon nanotubes (CNTs), one of the most promising carbon-related nanomaterials, have already achieved much success in biomedical field. Due to their excellent optical property, thermal and electronic conductivity, easy functionalization ability and high drug loading capacity, CNTs can be applied in a multifunctional way for cancer treatment and diagnosis. In this review, we will give an overview of the recent progress of CNT-based drug delivery systems in cancer theranostics, which emphasizes their targetability to intracellular components of tumor cells and extracellular elements in tumor microenvironment. Moreover, a detailed introduction on how CNTs penetrate inside the tumor cells to reach their sites of action and achieve the therapeutic effects, as well as their diagnostic applications will be highlighted.

Gemini Lipopeptide Bearing an Ultrashort Peptide for Enhanced Transfection Efficiency and Cancer-Cell-Specific Cytotoxicity

Cationic gemini lipopeptides are a relatively new class of amphiphilic compounds to be used for gene delivery. Through the possibility of incorporating short peptides with cell-penetrating functionalities, these lipopeptides may be advantageous over traditional cationic lipids. Herein, we report the design, synthesis, and application of a novel cationic gemini lipopeptide for gene delivery. An ultrashort peptide, containing four amino acids, arginine-cysteine-cysteine-arginine, serves as a cationic head group, and two α-tocopherol moieties act as hydrophobic anchoring groups. The new lipopeptide (ATTA) is incorporated into the conventional liposomes, containing 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) and 1,2-dioleoyl-sn-glycerol-3-phosphoethanolamine (DOPE), at different molar ratios. The formulated liposomes are characterized and screened for better transfection efficiency. Transfection activity in multiple human cell lines from cancerous and noncancerous origins indicates that the inclusion of an optimal ratio of ATTA in the liposomes substantially enhances the transfection efficiency, superior to that of a traditional liposome, DOTAP-DOPE. Cytotoxicity of ATTA-containing formulations against multiple cell lines indicates potentially distinct activity between cancer and noncancer cell lines. Furthermore, lipoplexes of the ATTA-containing formulations with anticancer therapeutic gene, plasmid encoding tumor necrosis factor-related apoptosis-inducing ligand (pTRAIL), induce obviously more cytotoxicity than conventional formulations. The results indicate that arginine-rich cationic lipopeptide appears to be a promising ingredient in gene delivery vector formulations to enhance transfection efficiency and cell-selective cytotoxicity.

Redox modulation of vitagenes via plant polyphenols and vitamin D: Novel insights for chemoprevention and therapeutic interventions based on organoid technology

Polyphenols are chemopreventive through the induction of nuclear factor erythroid 2 related factor 2 (Nrf2)-mediated proteins and anti-inflammatory pathways. These pathways, encoding cytoprotective vitagenes, include heat shock proteins, such as heat shock protein 70 (Hsp70) and heme oxygenase-1 (HO-1), as well as glutathione redox system to protect against cancer initiation and progression. Phytochemicals exhibit biphasic dose responses on cancer cells, activating at low dose, signaling pathways resulting in upregulation of vitagenes, as in the case of the Nrf2 pathway upregulated by hydroxytyrosol (HT) or curcumin and NAD/NADH-sirtuin-1 activated by resveratrol. Here, the importance of vitagenes in redox stress response and autophagy mechanisms, as well as the potential use of dietary antioxidants in the prevention and treatment of multiple types of cancer are discussed. We also discuss the possible relationship between SARS-CoV-2, inflammation and cancer, exploiting innovative therapeutic approaches with HT-rich aqueous olive pulp extract (Hidrox®), a natural polyphenolic formulation, as well as the rationale of Vitamin D supplementation. Finally, we describe innovative approaches with organoids technology to study human carcinogenesis in preclinical models from basic cancer research to clinical practice, suggesting patient-derived organoids as an innovative tool to test drug toxicity and drive personalized therapy.

Nanobiotechnology and Immunotherapy: Two Powerful and Cooperative Allies against Cancer

A number of novel cancer therapies have recently emerged that have rapidly moved from the bench to the clinic. Onco-immunotherapies, such as immune checkpoint blockade inhibitors and adoptive cell therapies, have revolutionized the field, since they provide a way to induce strong anti-tumor immune responses, which are able to fight cancer effectively. However, despite showing great efficacy in hematological and some solid tumors, unresponsiveness, development of therapy resistance and the development of serious adverse effects, limit their capacity to impact the vast majority of tumors. Nanoparticle-based delivery systems are versatile vehicles for a wide variety of molecular cargoes and provide an innovative strategy to improve conventional onco-immunotherapies. They can be finely tuned to release their contents in the tumor microenvironment, or to deliver combinations of adjuvants and antigens in the case of nanovaccines. In this review, we summarize the recent advancements in the field of nanobiotechnology, to remodel the tumor microenvironment and to enhance immunotherapies.

Adsorption and Release of Sulfamethizole from Mesoporous Silica Nanoparticles Functionalised with Triethylenetetramine

Mesoporous silica nanoparticles (MSN) were synthesised and functionalised with triethylenetetramine (MSN-TETA). The samples were fully characterised (transmission electron microscopy, small angle X-ray scattering, Fourier transform infrared spectroscopy, thermogravimetric analysis, zeta potential and nitrogen adsorption/desorption isotherms) and used as carriers for the adsorption of the antimicrobial drug sulphamethizole (SMZ). SMZ loading, quantified by UV-Vis spectroscopy, was higher on MSN-TETA (345.8 mg g-1) compared with bare MSN (215.4 mg g-1) even in the presence of a lower surface area (671 vs. 942 m2 g-1). The kinetics of SMZ adsorption on MSN and MSN-TETA followed a pseudo-second-order model. The adsorption isotherm is described better by a Langmuir model rather than a Temkin or Freundlich model. Release kinetics showed a burst release of SMZ from bare MSN samples (k1 = 136 h-1) in contrast to a slower release found with MSN-TETA (k1 = 3.04 h-1), suggesting attractive intermolecular interactions slow down SMZ release from MSN-TETA. In summary, the MSN surface area did not influence SMZ adsorption and release. On the contrary, the design of an effective drug delivery system must consider the intermolecular interactions between the adsorbent and the adsorbate.

Light-Responsive Micelles Loaded With Doxorubicin for Osteosarcoma Suppression

The enhancement of tumor targeting and cellular uptake of drugs are significant factors in maximizing anticancer therapy and minimizing the side effects of chemotherapeutic drugs. A key challenge remains to explore stimulus-responsive polymeric nanoparticles to achieve efficient drug delivery. In this study, doxorubicin conjugated polymer (Poly-Dox) with light-responsiveness was synthesized, which can self-assemble to form polymeric micelles (Poly-Dox-M) in water. As an inert structure, the polyethylene glycol (PEG) can shield the adsorption of protein and avoid becoming a protein crown in the blood circulation, improving the tumor targeting of drugs and reducing the cardiotoxicity of doxorubicin (Dox). Besides, after ultraviolet irradiation, the amide bond connecting Dox with PEG can be broken, which induced the responsive detachment of PEG and enhanced cellular uptake of Dox. Notably, the results of immunohistochemistry in vivo showed that Poly-Dox-M had no significant damage to normal organs. Meanwhile, they showed efficient tumor-suppressive effects. This nano-delivery system with the light-responsive feature might hold great promises for the targeted therapy for osteosarcoma.

Current Landscape in Organic Nanosized Materials Advances for Improved Management of Colorectal Cancer Patients

Globally, colorectal cancer (CRC) ranks as one of the most prevalent types of cancers at the moment, being the second cause of cancer-related deaths. The CRC chemotherapy backbone is represented by 5-fluorouracil, oxaliplatin, irinotecan, and their combinations, but their administration presents several serious disadvantages, such as poor bioavailability, lack of tumor specificity, and susceptibility to multidrug resistance. To address these limitations, nanomedicine has arisen as a powerful tool to improve current chemotherapy since nanosized carriers hold great promise in improving the stability and solubility of the drug payload and enhancing the active concentration of the drug that reaches the tumor tissue, increasing, therefore, the safety and efficacy of the treatment. In this context, the present review offers an overview of the most recent advances in the development of nanosized drug-delivery systems as smart therapeutic tools in CRC management and highlights the emerging need for improving the existing in vitro cancer models to reduce animal testing and increase the success of nanomedicine in clinical trials.

PPARs and Tumor Microenvironment: The Emerging Roles of the Metabolic Master Regulators in Tumor Stromal-Epithelial Crosstalk and Carcinogenesis

Peroxisome proliferator-activated receptors (PPARs) have been extensively studied for more than three decades. Consisting of three isotypes, PPARα, γ, and β/δ, these nuclear receptors are regarded as the master metabolic regulators which govern many aspects of the body energy homeostasis and cell fate. Their roles in malignancy are also increasingly recognized. With the growing interest in crosstalk between tumor stroma and epithelium, this review aims to highlight the current knowledge on the implications of PPARs in the tumor microenvironment. PPARγ plays a crucial role in the metabolic reprogramming of cancer-associated fibroblasts and adipocytes, coercing the two stromal cells to become substrate donors for cancer growth. Fibroblast PPARβ/δ can modify the risk of tumor initiation and cancer susceptibility. In endothelial cells, PPARβ/δ and PPARα are pro- and anti-angiogenic, respectively. Although the angiogenic role of PPARγ remains ambiguous, it is a crucial regulator in autocrine and paracrine signaling of cancer-associated fibroblasts and tumor-associated macrophages/immune cells. Of note, angiopoietin-like 4 (ANGPTL4), a secretory protein encoded by a target gene of PPARs, triggers critical oncogenic processes such as inflammatory signaling, extracellular matrix derangement, anoikis resistance and metastasis, making it a potential drug target for cancer treatment. To conclude, PPARs in the tumor microenvironment exhibit oncogenic activities which are highly controversial and dependent on many factors such as stromal cell types, cancer types, and oncogenesis stages. Thus, the success of PPAR-based anticancer treatment potentially relies on innovative strategies to modulate PPAR activity in a cell type-specific manner.

Recent Developments on Semiconducting Polymer Nanoparticles as Smart Photo-Therapeutic Agents for Cancer Treatments-A Review

Semiconducting polymer nanoparticles (SPN) have been emerging as novel functional nano materials for phototherapy which includes PTT (photo-thermal therapy), PDT (photodynamic therapy), and their combination. Therefore, it is important to look into their recent developments and further explorations specifically in cancer treatment. Therefore, the present review describes novel semiconducting polymers at the nanoscale, along with their applications and limitations with a specific emphasis on future perspectives. Special focus is given on emerging and trending semiconducting polymeric nanoparticles in this review based on the research findings that have been published mostly within the last five years.