Localized Microsphere/Hydrogel for Tumor Immunotherapy of Cardiac Glycoside with Minimal Toxicity

Plant-derived natural compounds: A new frontier in inducing immunogenic cell death for cancer treatment

Immunogenic cell death (ICD) can activate adaptive immune response in the host with normal immune system. Some synthetic chemotherapeutic drugs and natural compounds have shown promising results in cancer treatment by triggering the release of damage-associated molecules (DAMPs) to trigger ICD. However, most chemotherapeutic drugs exhibit non-selective cytotoxicity and may also induce and promote metastasis, thereby significantly reducing their clinical efficacy. Among the natural compounds that can induce ICD, plant-derived compounds account for the largest proportion, which are of increasing value in the treatment of cancer. Understanding which plant-derived natural compounds can induce ICD and how they induce ICD is crucial for developing strategies to improve chemotherapy outcomes. In this review, we focus on the recent findings regarding plant-derived natural compounds that induce ICD according to the classification of flavonoids, alkaloids, glycosides, terpenoids and discuss the potential mechanisms including endoplasmic reticulum (ER) stress, DNA damage, apoptosis, necroptosis autophagy, ferroptosis. In addition, plant-derived natural compounds that can enhance the ICD induction ability of conventional therapies for cancer treatment is also elaborated. The rational use of plant-derived natural compounds to induce ICD is helpful for the development of new cancer treatment methods.

Emerging role of immunogenic cell death in cancer immunotherapy: Advancing next-generation CAR-T cell immunotherapy by combination

Immunogenic cell death (ICD) is a stress-driven form of regulated cell death (RCD) in which dying tumor cells' specific signaling pathways are activated to release damage-associated molecular patterns (DAMPs), leading to the robust anti-tumor immune response as well as a reversal of the tumor immune microenvironment from "cold" to "hot". Chimeric antigen receptor (CAR)-T cell therapy, as a landmark in anti-tumor immunotherapy, plays a formidable role in hematologic malignancies but falls short in solid tumors. The Gordian knot of CAR-T cells for solid tumors includes but is not limited to, tumor antigen heterogeneity or absence, physical and immune barriers of tumors. The combination of ICD induction therapy and CAR-T cell immunotherapy is expected to promote the intensive use of CAR-T cell in solid tumors. In this review, we summarize the characteristics of ICD, stress-responsive mechanism, and the synergistic effect of various ICD-based therapies with CAR-T cells to effectively improve anti-tumor capacity.

Endoplasmic Reticulum-Targeting AIE Photosensitizers to Boost Immunogenic Cell Death for Immunotherapy of Bladder Carcinoma

Bladder cancer is characterized by high rates of recurrence and multifocality. Immunogenic cell death (ICD) of cancer cells has emerged as a promising strategy to improve the immunogenicity of tumor cells for enhanced cancer immunotherapy. Although photosensitizer-based photodynamic therapy (PDT) has been validated as capable of inducing ICD in cancer cells, the photosensitizers with a sufficient ICD induction ability are still rare, and there have been few reports on the development of advanced photosensitizers to strongly evoke the ICD of bladder cancer cells for eliciting potent antitumor immune responses and eradicating bladder carcinoma in situ. In this work, we have synthesized a new kind of endoplasmic reticulum (ER)-targeting aggregation-induced emission (AIE) photosensitizer (named DPASCP-Tos), which could effectively anchor to the cellular ER and trigger focused reactive oxygen species (ROS) production within the ER, thereby boosting ICD in bladder cancer cells. Furthermore, we have demonstrated that bladder cancer cells killed by ER-targeted PDT could serve as a therapeutic cancer vaccine to elicit a strong antitumor immunity. Prophylactic vaccination of the bladder cancer cells killed by DPASCP-Tos under light irradiation promoted the maturation of dendritic cells (DCs) and the expansion of tumor antigen-specific CD8+ T cells in vivo and protected mice from subsequent in situ bladder tumor rechallenge and extended animal survival. In summary, the ER-targeted AIEgens developed here significantly amplified the ICD of bladder cells through focused ROS-based ER oxidative stress and transformed bladder cancer cells into the therapeutic vaccine to enhance immunogenicity against orthotopic bladder cancer, providing valuable insights for bladder carcinoma treatment.

Harnessing the power of traditional Chinese medicine monomers and compound prescriptions to boost cancer immunotherapy

At present, cancer is the largest culprit that endangers human health. The current treatment options for cancer mainly include surgical resection, adjuvant radiotherapy and chemotherapy, but their therapeutic effects and long-term prognosis are unsatisfactory. Immunotherapy is an emerging therapy that has completely transformed the therapeutic landscape of advanced cancers, and has tried to occupy a place in the neoadjuvant therapy of resectable tumors. However, not all patients respond to immunotherapy due to the immunological and molecular features of the tumors. Traditional Chinese Medicine (TCM) provides a new perspective for cancer treatment and is considered to have the potential as promising anti-tumor drugs considering its immunoregulatory properties. This review concludes commonly used TCM monomers and compounds from the perspective of immune regulatory pathways, aiming to clearly introduce the basic mechanisms of TCM in boosting cancer immunotherapy and mechanisms of several common TCM. In addition, we also summarized closed and ongoing trials and presented prospects for future development. Due to the significant role of immunotherapy in the treatment of non-small cell lung cancer (NSCLC), TCM combined with immunotherapy should be emphasized in NSCLC.

Photocrosslinked methacrylated natural macromolecular hydrogels for tissue engineering: A review

A hydrogel is a three-dimensional (3D) network structure formed through polymer crosslinking, and these have emerged as a popular research topic in recent years. Hydrogel crosslinking can be classified as physical, chemical, or enzymatic, and photocrosslinking is a branch of chemical crosslinking. Compared with other methods, photocrosslinking can control the hydrogel crosslinking initiation, crosslinking time, and crosslinking strength using light. Owing to these properties, photocrosslinked hydrogels have important research prospects in tissue engineering, in situ gel formation, 3D bioprinting, and drug delivery. Methacrylic anhydride modification is a common method for imparting photocrosslinking properties to polymers, and graft-substituted polymers can be photocrosslinked under UV irradiation. In this review, we first introduce the characteristics of common natural polysaccharide- and protein-based hydrogels and the processes used for methacrylate group modification. Next, we discuss the applications of methacrylated natural hydrogels in tissue engineering. Finally, we summarize and discuss existing methacrylated natural hydrogels in terms of limitations and future developments. We expect that this review will help researchers in this field to better understand the synthesis of methacrylate-modified natural hydrogels and their applications in tissue engineering.

Differential Activities of the Botanical Extract PBI-05204 and Oleandrin on Innate Immune Functions under Viral Challenge Versus Inflammatory Culture Conditions

The Nerium oleander extract PBI 05204 (PBI) and its cardiac glycoside constituent oleandrin have direct anti-viral properties. Their effect on the immune system, however, is largely unknown. We used an in vitro model of human peripheral blood mononuclear cells to document effects under three different culture conditions: normal, challenged with the viral mimetic polyinosinic:polycytidylic acid Poly I:C, and inflamed by lipopolysaccharide (LPS). Cells were evaluated for immune activation marks CD69, CD25, and CD107a, and culture supernatants were tested for cytokines. Both PBI and oleandrin directly activated Natural Killer (NK) cells and monocytes and triggered increased production of cytokines. Under viral mimetic challenge, PBI and oleandrin enhanced the Poly I:C-mediated immune activation of monocytes and NK cells and enhanced production of IFN-γ. Under inflammatory conditions, many cytokines were controlled at similar levels as in cultures treated with PBI and oleandrin without inflammation. PBI triggered higher levels of some cytokines than oleandrin. Both products increased T cell cytotoxic attack on malignant target cells, strongest by PBI. The results show that PBI and oleandrin directly activate innate immune cells, enhance anti-viral immune responses through NK cell activation and IFN-γ levels, and modulate immune responses under inflamed conditions. The potential clinical impact of these activities is discussed.

Nanoarchitecture-Integrated Hydrogel Systems toward Therapeutic Applications

Hydrogels, as one of the most feasible soft biomaterials, have gained considerable attention in therapeutic applications by virtue of their tunable properties including superior patient compliance, good biocompatibility and biodegradation, and high cargo-loading efficiency. However, hydrogel application is still limited by some challenges like inefficient encapsulation, easy leakage of loaded cargoes, and the lack of controllability. Recently, nanoarchitecture-integrated hydrogel systems were found to be therapeutics with optimized properties, extending their bioapplication. In this review, we briefly presented the category of hydrogels according to their synthetic materials and further discussed the advantages in bioapplication. Additionally, various applications of nanoarchitecture hybrid hydrogels in biomedical engineering are systematically summarized, including cancer therapy, wound healing, cardiac repair, bone regeneration, diabetes therapy, and obesity therapy. Last, the current challenges, limitations, and future perspectives in the future development of nanoarchitecture-integrated flexible hydrogels are addressed.