Injectable cold atmospheric plasma-activated immunotherapeutic hydrogel for enhanced cancer treatment

Cold atmospheric plasma control metabolic syndromes via targeting fat mass and obesity-associated protein

Both obesity and metabolic disorders are global medical problems. Driven by prolonged inflammation, obesity increases the risk of developing metabolic syndromes such as fatty liver, diabetes, cardiovascular diseases and cancers. The fat mass and obesity-associated protein (FTO) is an m6A demethylase, elevated activity of which is known to promote the pathogenesis of many metabolic disorders, leading to the establishment of various FTO inhibitors. By combing through intrinsic connections among obesity and the four primary metabolic problems, we attribute their shared pathological cause to prolonged inflammation. By reviewing the roles of FTO in promoting these disorders and the current status of existing FTO inhibitors in treating these syndromes, we underpinned the paramount potential of resolving these clinical issues by targeting FTO and the urgent need of establishing novel FTO inhibitors with maximized efficacy and minimized side effect. Cold atmospheric plasma (CAP) is the fourth state of matter with demonstrated efficacy in treating various diseases associated with chronic inflammation. By introducing the medical characteristics of CAP, we proposed it as a possible solution to unresolved issues of current FTO inhibitors given its anti-inflammation feature and demonstrated clinical safety. We also emphasized the need of intensive investigations in exploring the feasibility of using CAP in treating obesity and associated metabolic syndromes that might function through targeting FTO.

Cold Atmospheric Plasma in Oncology: A Review and Perspectives on Its Application in Veterinary Oncology

Cold atmospheric plasma (CAP) is emerging as an innovative approach for cancer treatment because of its selectivity for malignant cells and absence of significant adverse effects. While modern oncological therapies face challenges such as tumor heterogeneity and treatment resistance, CAP presents itself as a low-cost and environmentally sustainable alternative. Its mechanisms of action involve reactive oxygen and nitrogen species (RONS), UV radiation, and electromagnetic fields, which induce cell death. Preclinical and clinical studies have demonstrated the efficacy of CAP, with devices such as dielectric barrier discharge (DBD) and the plasma jet developed to minimize damage to healthy cells. Some CAP devices are already approved for clinical use, showing safety and efficacy. However, the standardization of treatments remains a challenge due to the variety of devices and parameters used. Although CAP has shown promising cytotoxic effects in vitro and in animal models, especially in different cancer cell lines, further research, particularly in vivo and in veterinary medicine, is needed to optimize its clinical use and maximize its efficacy in combating cancer.

Biomimetic Hydrogels - Tools for Regenerative Medicine, Oncology, and Understanding Medical Gas Plasma Therapy

Biomimetic hydrogels enable biochemical, cell biology, and tissue-like studies in the third dimension. Smart hydrogels are also frequently used in tissue engineering and as drug carriers for intra- or extracutaneous regenerative medicine. They have also been studied in bio-sensor development, 3D cell culture, and organoid growth optimization. Yet, many hydrogel types, adjuvant components, and cross-linking methods have emerged over decades, diversifying and complexifying such studies. Here, an evaluative overview is provided, mapping potential applications to the corresponding hydrogel tuning. Strikingly, hydrogels are ideal for studying locoregional therapy modalities, such as cold medical gas plasma technology. These partially ionized gases produce various reactive oxygen species (ROS) types along with other physico-chemical components such as ions and electric fields, and the spatio-temporal effects of these components delivered to diseased tissues remain largely elusive to date. Hence, this work outlines the promising applications of hydrogels in biomedical research in general and cold plasma science in particular and underlines the great potential of these smart scaffolds for current and future research and therapy.

RSL3-loaded nanoparticles amplify the therapeutic potential of cold atmospheric plasma

Cold atmospheric plasma (CAP) has exhibited exciting potential for cancer treatment. Reactive oxygen and nitrogen species (RONS), the primary constituents in CAP, contribute to cancer cell death by elevating oxidative stress in cells. However, several intrinsic cellular antioxidant defense systems exist, such as the glutathione peroxidase 4 (GPX4) enzyme, which dampens the cell-killing efficacy of CAP. RAS-selective lethal 3 (RSL3), also known as a ferroptosis inducer, is a synthetic GPX4 inhibitor. Therefore, we hypothesized that RSL3 can amplify CAP-induced cell death by inhibition of GPX4. In this study, we showed that RSL3 loaded in poly (ethylene glycol)-block-poly(lactide-co-glycolide) (PLGA-PEG) nanoparticles can enhance CAP-induced cell deaths in 4T1 tumor cells. Furthermore, the combination of CAP and RSL3 also promoted cancer immunogenic cell death (ICD), induced dendritic cell (DC) maturation, and macrophage polarization, initiating tumor-specific T-cell mediated immune responses against tumors. For in vivo application, RSL3@NP was co-delivered with CAP via injectable Pluronic hydrogel. In 4T1-bearing mice, hydrogel-mediated delivery of CAP and RSL3-loaded nanoparticles can effectively elicit potent anti-tumor immune responses and inhibit tumor growth.

Healing wounds with plasma-activated hydrogel therapy

Chronic wound infections are a silent pandemic in danger of becoming a global healthcare crisis. Innovations to control infections and improve healing are required. In the context of this challenge, researchers are exploiting plasma-activated hydrogel therapy (PAHT) for use either alone or in combination with other antimicrobial strategies. PAHT involves the cold atmospheric pressure plasma activation of hydrogels with reactive oxygen and nitrogen species to decontaminate infections and promote healing. This opinion article describes PAHT for wound treatment and provides an overview of current research and outstanding challenges in translating the technology for medical use. A 'blueprint' of an autonomous PAHT is presented in the final section that can move the management and treatment of wounds from the clinical setting to the community.

Rationales of Cold Plasma Jet Therapy in Skin Cancer

Skin cancer affects millions of patients worldwide, and its incidence is increasing. Current therapies targeting skin tumour subtypes, such as basal cell carcinoma, cutaneous squamous cell carcinoma, melanoma and actinic keratosis, vary in their degree of effectiveness and tolerability, motivating new research avenues on complementing treatment strategies. Cold medical gas plasma is a partially ionised gas operated at about body temperature and generates various reactive oxygen and nitrogen species simultaneously. A range of medical gas plasma devices has proven safe in thousands of patients and is an approved medical product for dermatology conditions, such as nonhealing wounds, in Europe and, more broadly, for clinical trials. Extending potential gas plasma applications in the field of dermato-oncology is therefore plausible, especially in light of the strong preclinical evidence and early clinical data. This review summarises existing work on gas plasma treatment, focusing on approved jet plasmas in skin cancer and outlining central mechanisms and treatment concepts. It also provides a concrete perspective on integrating medical gas plasma treatment into existing skin cancer therapy schemes, encouraging translational scientists and clinicians to enable gas plasma-assisted cancer care through clinical research.

Antitumor effects of plasma‑activated solution on a murine melanoma model in vivo and in vitro

Melanoma is a common malignant skin tumor with highly invasive features and a high metastasis rate that can be difficult to treat clinically. Large-scale resection of primary cutaneous melanoma is often used to avoid postoperative recurrence. For advanced patients, radiotherapy, targeted therapy and immunotherapy are often needed. Low-temperature plasma has been proved to have significant antitumor effects on a variety of cancer cell lines cultured in vitro. The main limitation of direct low-temperature plasma treatment is that it has weak penetration ability and can only treat superficial lesions. In recent years, research on low-temperature plasma-activated solution has revealed that it also have good antitumor effects and low-temperature plasma penetration depth problems can be solved by local injection. The present study revealed that low-temperature plasma-activated phosphate buffer solution exhibited good antitumor effects and biosafety against melanoma in vitro and in vivo. It demonstrated that low-temperature plasma-activated solution has antitumor effects due to its regulation of intracellular redox, destruction of mitochondrial function and DNA damage. In vivo experiments demonstrated that treatment with low-temperature plasma-activated solution not only exhibited antitumor effects but also caused no significant damage to hematopoietic function or liver and kidney functions in mice. All these results demonstrated that low-temperature plasma-activated solution represent a promising antitumor treatment strategy.

The Genetic Expression Difference of A2058 Cells Treated by Plasma Direct Exposure and Plasma-Treated Medium and the Appropriate Treatment Strategy

Background/Objectives: Cold atmospheric plasma (CAP) has been demonstrated as an adjustable device to generate various combinations of short-lived reactive oxygen and nitrogen species (RONS) and as a promising appliance for cancer therapy. This study investigated the effects of direct and indirect treatments of Argon-based CAP to cancer cells (A2058, A549, U2OS and BCC) and fibroblasts (NIH3T3 and L929) on cell viability. We also aimed to understand whether plasma-generated RONS were involved in this process using genetic evidence. Methods: The intensity of reactive species in the plasma gas and the concentrations of RONS in phosphate-buffered saline (PBS) and cell culture medium were measured. A viability assay was performed after the cells were treated by plasma in PBS and medium with various volumes to realize the lethal effects of plasma under different conditions. Diverse cells were treated in the same solution to compare the sensitivities of different cells to plasma treatments. The gene expression profiles of A2058 cells after the direct and indirect treatments were analyzed by next generation gene sequencing. Accordingly, we discovered the advantages of sequential treatments on cancer therapy. Results: The cumulative concentration of hydroxyterephthalic acid (HTA) revealed that the pre-existing OH radical (•OH) in PBS increased with the treatment durations. However, there was no significant increase in the concentration of HTA in culture medium. HTA was detected in the treatment interface of PBS but not medium, showing the penetration of •OH through PBS. The concentrations of H2O2 and NO2- increased with the treatment durations, but that of NO3- was low. The direct treatments caused stronger lethal effects on cancer cells under certain conditions. The fibroblasts showed higher tolerance to plasma treatments. From gene expression analysis, the initial observations showed that both treatments influenced transcription-related pathways and exhibited shared or unique cellular stress responses. The pre-treatments, especially of direct exposure, revealed better cancer inhibition. Conclusions: The anti-cancer efficiency of plasma could be enhanced by pre-treatments and by adjusting the liquid interfaces to avoid the rapid consumption of short-lived RONS in the medium. To achieve better therapeutic effects and selectivity, more evidence is necessary to find optional plasma treatments.

Effects of no-ozone cold plasma and mouse mesenchymal stem cell treatments on wound healing in a mouse skin model

Skin wounds heal faster during stem cell differentiation. Cold plasma reportedly enhances cell proliferation and differentiation and enhances the efficacy of stem cell therapy. However, the exact mechanism of action involved remains unknown. Therefore, this study aimed to evaluate the effect of a combination therapy involving the transplantation of mouse mesenchymal stem cells (mMSCs) into mice with wounds followed by their activation using no-ozone cold plasma (NCP). Balb/c mMSCs were transplanted into BALB/c mice and treated with NCP for 5 min. The animals were divided into four groups based on treatments received: no treatment (Wound), mMSCs only (mMSC), NCP only (NCP), and both mMSC and NCP (mMSC + NCP). NCP treatment was administered six times over two weeks, and tissue samples were prepared by sacrificing the mice in the 1st and 2nd weeks. The wound healing efficacy was assessed using morphological, histological, and molecular approaches including wound healing length measurements, hematoxylin and eosin staining, Masson trichrome staining, immunofluorescence staining, immunohistochemistry, and real-time polymerase chain reaction. The wound healing effect was better in the mMSC + NCP group than that in the groups treated with either. Tracking the injected mMSCs in mice also revealed that the mMSC + NCP group had a greater survival rate. Furthermore, upon wound healing, the mMSC + NCP group exhibited elevated levels of growth factors, like platelet-derived growth factor, transforming growth factor-beta, and vascular endothelial growth factor. These results suggest that NCP stimulated transplanted mMSCs, resulting in faster wound healing. Therefore, further studies are warranted in preclinical and clinical studies to confirm this effect.

Targeting cholangiocarcinoma cells by cold piezoelectric plasmas: in vitro efficacy and cellular mechanisms

Cold piezoelectric plasma (CPP) is a novel approach in cancer therapy, enabling the development of portable treatment devices capable of triggering cancer cell death. While its effectiveness remains underexplored, this research focuses on its application against cholangiocarcinoma (CCA), an aggressive cancer of the biliary tract. A CPP device is utilized to generate either a corona discharge (Pz-CD) or a dielectric barrier discharge (Pz-DBD) for in vitro experiments. Notably, Pz-CD can deliver more power than Pz-DBD, although both sources produce significant levels of reactive species in plasma and liquid phases. This work shows that CPP causes a gradient increase in medium temperature from the center towards the edges of the culture well, especially for longer treatment times. Although Pz-CD heats more significantly, it cools quickly after plasma extinction. When applied to human CCA cells, CPP shows immediate and long-term effects, more localized for Pz-CD, while more uniform for Pz-DBD. Immediate effects result also in actin cytoskeleton remodeling without alteration of the cell membrane permeability. Long-term effects of CPP, although the antioxidant system is engaged, include activation of the DNA damage response pathway leading to cell death. In conclusion, CPP should be recognized as a promising antitumor therapy.

Hydrogel local drug delivery systems for postsurgical management of tumors: Status Quo and perspectives

Surgery is one of the primary treatments for solid tumors. However, the incomplete resection of tumor cells and the immunosuppressive microenvironment make the issue of postsurgical tumor recurrence a great challenge. Furthermore, a wide range of requirements, including ensuring effective hemostasis, implementing prophylactic measures against infection, and promoting wound healing, were also raised in the postsurgical management of tumors. To fulfill these demands, multiple hydrogel local drug delivery systems (HLDDS) were developed recently. These HLDDS are expected to offer numerous advantages in the postsurgical management of tumors, such as achieving high local drug concentrations at the lesion, efficient delivery to surgical microcavities, mitigating systemic side effects, and addressing the diverse demand. Thus, in this review, a detailed discussion of the diverse demands of postsurgical management of tumors is provided. And the current publication trend on HLDDS in the postsurgical management of tumors is analyzed and discussed. Then, the applications of different types of HLDDS, in-situ HLDDS and non-in-situ HLDDS, in postsurgical management of tumors were introduced and summarized. Besides, the current problems and future perspectives are discussed. The review is expected to provide an overview of HLDDS in postsurgical management of tumors and promote their clinical application.

Adhesive lipophilic gels delivering rapamycin prevent oral leukoplakia from malignant transformation

Oral leukoplakia (OLK) is the most emblematic oral potentially malignant disorder that may precede the diagnosis of oral squamous cell carcinoma (OSCC) and has an overall malignant transformation rate of 9.8 %. Early intervention is crucial to reduce the malignant transformation rate from OLK to OSCC but the lack of effective local pharmaceutical preparations poses a challenge to clinical management. Rapamycin is speculated to prevent OLK from carcinogenesis and its inherent lipophilicity facilitates its penetration into stratum corneum. Nevertheless, hydrophilic hydrogels frequently encounter challenges when attempting to deliver lipophilic drugs. Furthermore, the oral cavity presents a complex environment defined by oral motor functions, saliva secretion cycles, dynamic fluctuations, and protective barriers comprising mucus and lipid layers. Consequently, addressing issues of muco-penetration and muco-adhesion is imperative for developing an effective drug delivery system aiming at delivering rapamycin to target oral potentially malignant disorders. Here, a dual-function hydrogel drug delivery system integrating adhesion and lipophilicity was successfully developed based on polyvinyl alcohol (PVA) and dioleoyl phosphatidylglycerol (DOPG) via dynamic boronic ester bonds. Rheological experiments based on orthogonal design revealed that PVA-DOPG hydrogels exhibited ideal adhesive strength (around 6 kPa) and could adhere to various surfaces in both dry and wet conditions. PVA-DOPG hydrogels also significantly promoted lipophilic molecules' penetration into stratum corneum (integrated fluorescence density of 6.95 ± 0.52 × 106 and mean fluorescence depth of 0.96 ± 0.07 mm) of ex-vivo porcine buccal mucosa (p < 0.001). Furthermore, PVA-DOPG hydrogels incorporating rapamycin inhibited malignant transformation of OLK mouse model induced by 4-Nitroquinoline N-oxide (4-NQO), distinct improvements in survival (the neoplasm incidence density at the 40th day is 0.0091) (p < 0.05), decrease in neoplasm incidence density of 36.36 % and inhibition rate in neoplasm volume of 75.04 ± 33.67 % have been demonstrated, suggesting the hydrogels were valuable candidates for potential applications in the management of OLK.

Advancements and challenges in brain cancer therapeutics

Treating brain tumors requires a nuanced understanding of the brain, a vital and delicate organ. Location, size, tumor type, and surrounding tissue health are crucial in developing treatment plans. This review comprehensively summarizes various treatment options that are available or could be potentially available for brain tumors, including physical therapies (radiotherapy, ablation therapy, photodynamic therapy, tumor-treating field therapy, and cold atmospheric plasma therapy) and non-physical therapies (surgical resection, chemotherapy, targeted therapy, and immunotherapy). Mechanisms of action, potential side effects, indications, and latest developments, as well as their limitations, are highlighted. Furthermore, the requirements for personalized, multi-modal treatment approaches in this rapidly evolving field are discussed, emphasizing the balance between efficacy and patient safety.

Advances in cancer diagnosis and therapy by alginate-based multifunctional hydrogels: A review

The field of oncology has been changed by the application of hydrogels. These 3D polymeric networks have demonstrated significant promise in the treatment of cancer and can boost the efficacy of conventional therapeutics including chemotherapy and immunotherapy. Noteworthy, the development of biocompatible and effective hydrogels has been of interest. In this case, alginate as a biopolymer and carbohydrate polymer has been used to modify or synthesis multifunctional nanoparticles for the treatment of human diseases, especially cancer. Therefore, highlighting the function of alginate in the development of hydrogels in cancer therapy can provide new insights for improving outcome and survival rate of patients. Alginate hydrogels improve the specific and selective delivery of cargo and therefore, they reduce the systemic toxicity of drugs, while they enhance anti-cancer activity. Alginate hydrogels protect the genes against degradation by enzymes and increase blood circulation time. The alginate hydrogels can respond to the specific stimuli in the tumor microenvironment including pH, redox and light to improve the site-specific release of cargo. The nanoparticles can be incorporated in the structure of alginate hydrogels to augment their anti-cancer activity. In addition, alginate hydrogels can accelerate immunotherapy and phototherapy through delivery of immunomodulators and photosensitizers, respectively.

Enhancing antitumor immunity in Lewis lung cancer through plasma-treated medium-induced activation of dendritic cells

BACKGROUND

Recently, atmospheric non-thermal plasma jet-treated medium (PTM) has been recognized as a novel strategy in cancer therapy and lymphocyte activation. However, PTM has limitations in inducing a robust antitumor-immune response. This study demonstrated that PTM treatment inhibited tumor progression by activating dendritic cells (DCs).

METHOD

In this study, we investigated the effects of PTM on selective cytotoxicity and intracellular reactive oxygen species (ROS) generation and oxidative stress-mediated signaling (e.g., glutathione peroxidase, catalase) using respective fluorescence probes in Lewis lung cancer (LLC) cells. Then, the PTM affects the expression of interferon-gamma (IFN)-γ-induced programmed death-ligand 1 (PD-L1) and inhibition of signal transducer and activator of transcription 1 (STAT1) in LLC cells using immunoblotting. Additionally, PTM effects on the tumor cell's death and activation of DCs were done by co-culturing DCs with or without tumor cells. Further, a mouse model was used to evaluate the synergistic antitumor effects of PTM and DCs where tumors are grown under the skin.

RESULTS

PTM-exposed tumor cells increase intracellular superoxide production, enhancing ROS generation and leading to cancer immunogenic cell death. In addition, PTM suppresses IFN-γ-induced PD-L1 expression and STAT1 activation in tumor cells. The activation of DCs induced by PTM is downregulated when these cells are co-cultured with tumor cells. In vivo, intraperitoneal injection of PTM-activated DCs, as a synergistic agent to intertumoral PTM treatment, led to increased CD4+ and CD8+ T cell infiltration into the tumor and spleen and eventually decreased tumor growth.

CONCLUSION

Overall, this research introduces a promising avenue for improving lung cancer treatment using PTM to stimulate an immune response and induce cell death in tumor cells. Further studies will be essential to validate these findings and explore clinical applications.

Emerging Strategies for Local Delivery of Immune Checkpoint Inhibitors to Potentiate Cancer Immunotherapy: Current Status and Future Prospects

Cancer constitutes a significant threat to patients' lives worldwide. Immunotherapy, particularly immune checkpoint inhibitors (ICIs) that boost antitumor immunity by targeting immune checkpoint components, has emerged as a promising strategy for its treatment in recent years. However, the objective response rates of the ICIs are unsatisfactory. As the primary route, systemic administration of ICIs is often accompanied by immune-related adverse events. Local delivery of ICIs serves as a potential therapeutic strategy that can improve the efficacy while simultaneously reducing side effects through precise drug release at the tumor site. Initial validation of direct local application of ICIs for tumors in clinical trials has indicated reduced side effects and improved efficacy, while low bioavailability remains a challenge. Furthermore, research on various carriers, including nanoparticles, microneedles, hydrogels, combined platforms, and implantable devices for local release of ICIs has exhibited applying potential in treating murine tumors, among which combined platforms such as combined hydrogel system hold the highest promise due to their encompassment of the advantages of multiple carriers. These carriers, by incorporating ICIs and other therapeutics, could manage cancers more potently, which needs to be confirmed in clinical trials after the refinement of their biocompatibility. This review summarizes the latest research advancements regarding local administration of ICIs, with a particular focus on the carriers for local delivery as well as the combination therapies, thus providing novel insights and research guidance for scholars to enhance the efficacy of locally delivered ICIs on managing multiple cancers in the future.

Plasma-Activated AVC Hydrogel for Reactive Oxygen and Nitrogen Species Delivery to Treat Allergic Contact Dermatitis

Allergic contact dermatitis (ACD) is a common inflammatory skin disease that accounts for approximately 20% of all occupational skin diseases. As an adverse and recurrent inflammatory dermatological agent, ACD shows insufficient response to current therapies largely owing to abnormal inflammatory activation and accompanying bacterial infection in lesions. Cold atmospheric plasma is a noninvasive fledgling reactive oxygen and nitrogen species (RONS)-based therapeutic technique for ACD treatment; however, its clinical adoption has been hindered due to the risk of electrical burns and insufficient delivery of the plasma-generated RONS. To address these limitations, we constructed plasma-activated AVC (PA-AVC) hydrogels loaded with plasma-generated RONS for ACD treatment as an alternative to the common direct plasma irradiation treatment. The proposed PA-AVC hydrogels were produced on a biodegradable acryloyldimethylammonium taurate/VP copolymer (AVC) with the aid of a novel air discharge plasma without the involvement of any catalyst. In vitro data showed that abundant RONS were produced and incorporated into the PA-AVC hydrogels via complex gas-liquid reactions between the air discharge plasma and hydrosolvent; additionally, the PA-AVC hydrogels exhibited excellent storage, slow release and transdermal delivery of RONS as well as good antibacterial effects. Moreover, in vivo experiments demonstrated that PA-AVC hydrogels effectively alleviated the ACD symptoms, such as skin redness and swelling, reduced epidermal thickening and inhibited mast cell infiltration and IL-9, TNF-α, and TSLP expression with no evident systemic toxicity. Our results revealed that long-acting plasma-activated AVC hydrogels could be effective therapeutic agents for local ACD treatment.

Innovative theranostic hydrogels for targeted gastrointestinal cancer treatment

Gastrointestinal tumors are the main causes of death among the patients. These tumors are mainly diagnosed in the advanced stages and their response to therapy is unfavorable. In spite of the development of conventional therapeutics including surgery, chemotherapy, radiotherapy and immunotherapy, the treatment of these tumors is still challenging. As a result, the new therapeutics based on (nano)biotechnology have been introduced. Hydrogels are polymeric 3D networks capable of absorbing water to swell with favorable biocompatibility. In spite of application of hydrogels in the treatment of different human diseases, their wide application in cancer therapy has been improved because of their potential in drug and gene delivery, boosting chemotherapy and immunotherapy as well as development of vaccines. The current review focuses on the role of hydrogels in the treatment of gastrointestinal tumors. Hydrogels provide delivery of drugs (both natural or synthetic compounds and their co-delivery) along with gene delivery. Along with delivery, hydrogels stimulate phototherapy (photothermal and photodynamic therapy) in the suppression of these tumors. Besides, the ability of hydrogels for the induction of immune-related cells such as dendritic cells can boost cancer immunotherapy. For more specific cancer therapy, the stimuli-responsive types of hydrogels including thermo- and pH-sensitive hydrogels along with their self-healing ability have improved the site specific drug delivery. Moreover, hydrogels are promising for diagnosis, circulating tumor cell isolation and detection of biomarkers in the gastrointestinal tumors, highlighting their importance in clinic. Hence, hydrogels are diagnostic and therapeutic tools for the gastrointestimal tumors.

Trehalose enhanced cold atmospheric plasma-mediated cancer treatment

Cold atmospheric plasma (CAP) is a unique form of physical plasma that has shown great potential for cancer therapy. CAP uses ionized gas to induce lethal oxidative stress on cancer cells; however, the efficacy of CAP therapy continues to be improved. Here, we report an injectable hydrogel-mediated approach to enhance the anti-tumor efficacy of CAP by regulating the phosphorylation of eIF2α. We discovered that reactive oxygen and nitrogen species (ROS/RNS), two main anti-tumor components in CAP, can lead to lethal oxidative stress on tumor cells. Elevated oxidative stress subsequently induces eIF2α phosphorylation, a pathognomonic marker of immunogenic cell death (ICD). Trehalose, a natural disaccharide sugar, can further enhance CAP-induced ICD by elevating the phosphorylation of eIF2α. Moreover, injectable hydrogel-mediated delivery of CAP/trehalose treatment promoted dendritic cell (DC) maturation, initiating tumor-specific T-cell mediated anti-tumor immune responses. The combination therapy also supported the polarization of tumor-associated macrophages to an M1-like phenotype, reversing the immunosuppressive tumor microenvironment and promoting tumor antigen presentation to T cells. In combination with immune checkpoint inhibitors (i.e., anti-programmed cell death protein 1 antibody, aPD1), CAP/trehalose therapy further inhibited tumor growth. Importantly, our findings also indicated that this hydrogel-mediated local combination therapy engaged the host systemic innate and adaptive immune systems to impair the growth of distant tumors.

Recent advancements of hydrogels in immunotherapy: Breast cancer treatment

Breast cancer is the most prevalent cancer among women and the leading cause of cancer-related deaths in this population. Recent advances in Immunotherapy, or combined immunotherapy, offering a more targeted and less toxic approach, expand the survival rate of patients more than conventional treatment. Notably, hydrogels, a versatile platform provided promising avenues to combat breast cancer in preclinical studies and extended to clinical practices. With advantages such as the alternation of tumor microenvironment, immunomodulation, targeted delivery of therapeutic agents, and their sustained release at specific sites of interest, hydrogels can potentially be used for the treatment of breast cancer. This review highlights the advantages, mechanisms of action, stimuli-responsiveness properties, and recent advancements of hydrogels for treating breast cancer immunotherapy. Moreover, post-treatment and its clinical translations are discussed in this review. The integration of hydrogels in immunotherapy strategies may pave the way for more effective, personalized, and patient-friendly approaches to combat breast cancer, ultimately contributing to a brighter future for breast cancer patients.

Cold atmospheric plasma-activated medium for potential ovarian cancer therapy

Cold atmospheric plasma (CAP) has emerged as an innovative tool with broad medical applications, including ovarian cancer (OC) treatment. By bringing CAP in close proximity to liquids such as water or cell culture media, solutions containing reactive oxygen species (ROS) and reactive nitrogen species (RNS) are generated, called plasma-activated media (PAM). In this systematic review, we conduct an in-depth analysis of studies focusing on PAM interactions with biological substrates. We elucidate the diverse mechanisms involved in the activation of different media and the complex network of chemical reactions underlying the generation and consumption of the prominent reactive species. Furthermore, we highlight the promises of PAM in advancing biomedical applications, such as its stability for extended periods under appropriate storage conditions. We also examine the application of PAM as an anti-cancer and anti-metastatic treatment for OC, with a particular emphasis on its ability to induce apoptosis via distinct signaling pathways, inhibit cell growth, suppress cell motility, and enhance the therapeutic effects of chemotherapy. Finally, the future outlook of PAM therapy in biomedical applications is speculated, with emphasis on the safety issues relevant to clinical translation.

An "All-In-One" Immunomodulator-Engineered Clinical Translatable Immunotherapy of Advanced Hepatocellular Carcinoma

Clinical treatment of advanced hepatocellular carcinoma (HCC) remains a significant challenge. Utilizing 1-bromoacetyl-3,3-dinitroazetidine (RRx-001) to downregulate the expression of innate immune checkpoint molecule, cluster of differentiation 47 (CD47), provides a powerful means for treating advanced HCC containing abundant immunosuppressive macrophages. Herein engineering of a previously optimized Doxorubicin (DOX)-delivery nanoplatform based on sodium alginate is reported to further co-deliver RRx-001 (biotinylated aldehyde alginate-doxorubicin micelle prodrug nanoplatform, BEA-D@R) for efficient immunotherapy of advanced HCC. This groundbreaking  technique reveals the "all-in-one" immunotherapeutic functionalities of RRx-001. Besides the previously demonstrated functions of downregulating CD47 expression and increasing reactive nitrogen species (RNS) generation, another key function of RRx-001 for downregulating the expression of the adaptive immune checkpoint molecule programmed cell death 1 ligand 1 (PDL1) is first uncovered here. Combined with the reactive oxygen species (ROS) generation and an upregulated "eat me" signal level of DOX, BEA-D@R collectively increases RNS generation, enhances T-cell infiltration, and maximizes macrophage phagocytosis, leading to an average of 40% tumor elimination in a mice model bearing an initial tumor volume of ≈300 mm3 that mimics advanced HCC. Overall, the "all-in-one" immunotherapeutic functionalities of a clinical translatable nanoplatform are uncovered for enhanced immunotherapy of advanced HCC.

Mechanism of non-thermal atmospheric plasma in anti-tumor: influencing intracellular RONS and regulating signaling pathways

Non-thermal atmospheric plasma (NTAP) has been proven to be an effective anti-tumor tool, with various biological effects such as inhibiting tumor proliferation, metastasis, and promoting tumor cell apoptosis. At present, the main conclusion is that ROS and RNS are the main effector components of NTAP, but the mechanisms of which still lack systematic summary. Therefore, in this review, we first summarized the mechanism by which NTAP directly or indirectly causes an increase in intracellular RONS concentration, and the multiple pathways dysregulation (i.e. NRF2, PI3K, MAPK, NF-κB) induced by intracellular RONS. Then, we generalized the relationship between NTAP induced pathways dysregulation and the various biological effects it brought. The summary of the anti-tumor mechanism of NTAP is helpful for its further research and clinical transformation.

Bioresponsive and immunotherapeutic nanomaterials to remodel tumor microenvironment for enhanced immune checkpoint blockade

Immune checkpoint blockade (ICB) therapy is a revolutionary approach to treat cancers, but still have limited clinical applications. Accumulating evidence pinpoints the immunosuppressive characteristics of the tumor microenvironment (TME) as one major obstacle. The TME, characterized by acidity, hypoxia and elevated ROS levels, exerts its detrimental effects on infiltrating anti-tumor immune cells. Here, we developed a TME-responsive and immunotherapeutic catalase-loaded calcium carbonate nanoparticles (termed as CAT@CaCO3 NPs) as the simple yet versatile multi-modulator for TME remodeling. CaCO3 NPs can consume protons in the acidic TME to normalize the TME pH. CAT catalyzed the decomposition of ROS and thus generated O2. The released Ca2+ led to Ca2+ overload in the tumor cells which then triggered the release of damage-associated molecular patterns (DAMP) signals to initiate anti-tumor immune responses, including tumor antigen presentation by dendritic cells. Meanwhile, CAT@CaCO3 NPs-induced immunosupportive TME also promoted the polarization of the M2 tumor-associated macrophages to the M1 phenotype, further enhancing tumor antigen presentation. Consequently, T cell-mediated anti-tumor responses were activated, the efficacy of which was further boosted by aPD-1 immune checkpoint blockade. Our study demonstrated that local treatment of CAT@CaCO3 NPs and aPD-1 combination can effectively evoke local and systemic anti-tumor immune responses, inhibiting the growth of treated tumors and distant diseases.

Cancer Metabolism: The Role of ROS in DNA Damage and Induction of Apoptosis in Cancer Cells

Cancer is a huge challenge for people worldwide. High reactive oxygen species (ROS) levels are a recognized hallmark of cancer and an important aspect of cancer treatment research. Abnormally elevated ROS levels are often attributable to alterations in cellular metabolic activities and increased oxidative stress, which affects both the development and maintenance of cancer. Moderately high levels of ROS are beneficial to maintain tumor cell genesis and development, while toxic levels of ROS have been shown to be an important force in destroying cancer cells. ROS has become an important anticancer target based on the proapoptotic effect of toxic levels of ROS. Therefore, this review summarizes the role of increased ROS in DNA damage and the apoptosis of cancer cells caused by changes in cancer cell metabolism, as well as various anticancer therapies targeting ROS generation, in order to provide references for cancer therapies based on ROS generation.