Nanobodies in cell-mediated immunotherapy: On the road to fight cancer

Imaging of tumor-associated macrophage dynamics during immunotherapy using a CD163-specific nanobody-based immunotracer

Immunotherapies have emerged as an effective treatment option for immune-related diseases, such as cancer and inflammatory diseases. However, variations in patient responsiveness limit the broad applicability and success of these immunotherapies. Noninvasive whole-body imaging of the immune status of individual patients during immunotherapy could enable the prediction and monitoring of the patient's response, resulting in more personalized treatments. In this study, we developed a nanobody-based immunotracer targeting CD163, a receptor specifically expressed on macrophages. This anti-CD163 immunotracer bound to human and mouse CD163 with high affinity and specificity without competing for ligand binding. Furthermore, the tracer showed no unwanted immune cell activation and was nonimmunogenic. Upon radiolabeling of the anti-CD163 immunotracer, specific imaging of CD163+ macrophages using micro-single-photon emission computerized tomography/computed tomography or micro-positron emission tomography/CT was performed. The anti-CD163 immunotracer was able to stratify immunotherapy responders from nonresponders (NR) by visualizing differences in the intratumoral CD163+ TAM distribution in Lewis lung carcinoma-ovalbumin tumor-bearing mice receiving an anti-programmed cell death protein-1 (PD-1)/CSF1R combination treatment. Immunotherapy-responding mice showed a more homogeneous distribution of the PET signal in the middle of the tumor, while CD163+ TAMs were located at the tumor periphery in NR. As such, visualization of CD163+ TAM distribution in the tumor microenvironment could allow a prediction or follow-up of therapy response. Altogether, this study describes an immunotracer, specific for CD163+ macrophages, that allows same-day imaging and follow-up of these immune cells in the tumor microenvironment, providing a good basis for the prediction and follow-up of immunotherapy responses in cancer patients.

CAR-armored-cell therapy in solid tumor treatment

Over the past decade, chimeric antigen receptor (CAR)-T cell therapy has emerged as a revolutionary immunotherapeutic approach to combat cancer. This therapy constructs a CAR on the surface of T cells through genetic engineering techniques. The CAR is formed from a combination of antibody-derived or ligand-derived domains and T-cell receptor (TCR) domains. This enables T cells to specifically bind to and activate against tumor cells. However, the efficacy of CAR-T cells in solid tumors remains inconclusive due to several challenges such as poor tumor trafficking, infiltration, and the immunosuppressive tumor microenvironment (TME). In response, CAR natural killer (CAR-NK) and CAR macrophages (CAR-M) have been developed as complementary strategies for solid tumors. CAR-NK cells do not require HLA compatibility, demonstrate reduced toxicity, and are thus seen as potential substitutes for CAR-T cells. Furthermore, CAR-M immunotherapy is also being researched and has shown phagocytic capabilities and tumor-antigen presentation. This study discusses the features, advantages, and limitations of CAR-T, CAR-NK, and CAR-M cells in the treatment of solid tumors and suggests prospective solutions for enhancing the efficacy of CAR host-cell-based immunotherapy.

A potent and selective anti-glutathione peroxidase 4 nanobody as a ferroptosis inducer

Glutathione peroxidase 4 (GPX4) plays a crucial role in the ferroptosis pathway, emerging as a potential drug target in the treatment of refractory tumors. Unfortunately, the development of GPX4-targeted treatment has been very limited due to the poor selectivity and drug-like properties of current GPX4 inhibitors. Here, we report a proof-of-concept study of potent anti-GPX4 nanobodies, successfully identified through immunizing Bactrian camels and constructing a phage library. Utilizing a cell-penetrating peptide fusion strategy, these nanobodies with high affinities to GPX4 efficiently internalized in cells and formed the basis for further applications. In particular, 12E significantly inhibited cellular GPX4 and consequently induced remarkable ferroptosis in cancer cells. Furthermore, 12E could impair zebrafish dorsal organizer formation in vivo, as evidenced by a phenotype comparable to that observed in zebrafish with the gpx4b gene knocked out. The new GPX4-inhibiting nanobody described here exhibits superior proteome-wide selectivity and a vastly improved safety profile compared to existing GPX4 inhibitors. These incredible features of 12E, as an anti-GPX4 nanobody, may not only contribute to ferroptosis-related anticancer treatment but also establish a new paradigm for nanobodies in drug development for traditionally undruggable targets.

Implication of Toll-Like Receptors in growth and management of health and diseases: Special focus as a promising druggable target to Prostate Cancer

Toll-like receptors (TLRs) are protein structures belonging to the pattern recognition receptors family. TLRs have the great potential that can directly recognize the specific molecular structures on the surface of pathogens, damaged senescent cells and apoptotic host cells. Available evidence suggests that TLRs have crucial roles in maintaining tissue homeostasis through control of the inflammatory and tissue repair responses during injury. TLRs are the player of first line of defense against different microbes and activate the signaling cascades which help to induce the immune system and inflammatory responses by affecting various signaling pathways, including nuclear factor-κB (NF-κB), interferon regulatory factors, and mitogen-activated protein kinases (MAPKs). TLRs have been identified to be over-expressed in different types of cancers and play an important role in control of health and management of diseases. The current review provides updated knowledge on the implication of TLRs in growth and management of cancers including prostate cancer.

The landscape of combining immune checkpoint inhibitors with novel Therapies: Secret alliances against breast cancer

This review focuses on the immune checkpoint inhibitors (ICIs) in the context of breast cancer (BC) management. These innovative treatments, by targeting proteins expressed on both tumor and immune cells, aim to overcome tumor-induced immune suppression and reactivate the immune system. The potential of this approach is the subject of numerous clinical studies. Here, we explore the key studies and emerging therapies related to ICIs providing a detailed analysis of their specific and combined use in BC treatment.

Screening, expression and anti-tumor functional identification of anti-LAG-3 nanobodies

OBJECTIVE

To screen and obtain specific anti-lymphocyte activation gene-3 (LAG3) nanobody sequences, purify and express recombinant anti-LAG3 nanobody, and verify its effect on promoting T cells to kill tumor cells.

METHODS

Based on the camel derived natural nanobody phage display library constructed by the research group, the biotinylated LAG3 antigen was used as the target, and the anti-LAG3 nanobody sequences were screened by biotin-streptavidin liquid phase screening, phage-ELISA and sequencing. The sequence-conjμgated human IgG1 Fc fragment was obtained, the recombinant anti-LAG3 nanobody expression vector was constructed, the expression of the recombinant anti-LAG3 nanobody was induced by IPTG and purified, and the characteristics and functions of the recombinant anti-LAG3 nanobody were verified by SDS-PAGE, Western blot, cytotoxicity assay, etc. RESULTS: One anti-LAG3 nanobody sequence was successfully screened, and the corresponding recombinant anti-LAG3 nanobody-expressing bacteria were constructed. The results of SDS-PAGE, Western blot and cytotoxicity assay showed that the recombinant anti-LAG3 nanobody was successfully expressed, which was specific, and it could promote the killing ability of T cells against tumor cells, and the optimal concentration was 200 μg/mL.

CONCLUSION

The recombinant anti-LAG3 nanobody screened and expressed has specific and auxiliary anti-tumor cell effects, which lays a foundation for its subsequent application.

Advancements in mammalian display technology for therapeutic antibody development and beyond: current landscape, challenges, and future prospects

The evolving development landscape of biotherapeutics and their growing complexity from simple antibodies into bi- and multi-specific molecules necessitates sophisticated discovery and engineering platforms. This review focuses on mammalian display technology as a potential solution to the pressing challenges in biotherapeutic development. We provide a comparative analysis with established methodologies, highlighting key aspects of mammalian display technology, including genetic engineering, construction of display libraries, and its pivotal role in hit selection and/or developability engineering. The review delves into the mechanisms underpinning developability-driven selection via mammalian display and their broader implications. Applications beyond antibody discovery are also explored, alongside advancements towards function-first screening technologies, precision genome engineering and AI/ML-enhanced libraries, situating them in the context of mammalian display. Overall, the review provides a comprehensive overview of the current mammalian display technology landscape, underscores the expansive potential of the technology for biotherapeutic development, addresses the critical challenges for the full realisation of this potential, and examines advances in related disciplines that might impact the future application of mammalian display technologies.

A nanobody-guided multifunctional T cell engager promotes strong anti-tumor responses via synergistic immuno-photothermal effects

BACKGROUND

T cell-based immunotherapies are facing great challenges in the recruitment and activation of tumor-specific T cells against solid tumors. Among which, utilizing nanobody (Nb) or nanobodies (Nbs) to construct T cell engager has emerged as a more practical potential for enhancing the anti-tumor effectiveness of T cells. Here, we designed a new Nb-guided multifunctional T cell engager (Nb-MuTE) that not only recruited effector T cells into the tumor tissues, but also efficiently activated T cells anti-tumor immunity when synergies with photothermal effect.

RESULTS

The Nb-MuTE, which was constructed based on an indocyanine green (ICG)-containing liposome with surface conjugation of CD105 and CD3 Nbs, and showed excellent targetability to both tumor and T cells, following enhancement of activation, proliferation and cytokine secretion of tumor-specific T cells. Notably, the immunological anti-tumor functions of Nb-MuTE-mediated T cells were further enhanced by the ICG-induced photothermal effect in vitro and in vivo.

CONCLUSIONS

Such a new platform Nb-MuTE provides a practical and "all-in-one" strategy to potentiate T cell responses for the treatment of solid tumor in clinic.

Polypeptides-Based Nanocarriers in Tumor Therapy

Cancer remains a worldwide problem, and new treatment strategies are being actively developed. Peptides have the characteristics of good biocompatibility, strong targeting, functional diversity, modifiability, membrane permeable ability, and low immunogenicity, and they have been widely used to construct targeted drug delivery systems (DDSs). In addition, peptides, as endogenous substances, have a high affinity, which can not only regulate immune cells but also work synergistically with drugs to kill tumor cells, demonstrating significant potential for application. In this review, the latest progress of polypeptides-based nanocarriers in tumor therapy has been outlined, focusing on their applications in killing tumor cells and regulating immune cells. Additionally, peptides as carriers were found to primarily provide a transport function, which was also a subject of interest to us. At the end of the paper, the shortcomings in the construction of peptide nano-delivery system have been summarized, and possible solutions are proposed therein. The application of peptides provides a promising outlook for cancer treatment, and we hope this article can provide in-depth insights into possible future avenues of exploration.

Recent updates on allogeneic CAR-T cells in hematological malignancies

CAR-T cell therapy is known as an effective therapy in patients with hematological malignancies. Since 2017, several autologous CAR-T cell (auto-CAR-T) drugs have been approved by the US Food and Drug Administration (FDA) for the treatment of some kinds of relapsed/refractory hematological malignancies. However, some patients fail to respond to these drugs due to high manufacturing time, batch-to-batch variation, poor quality and insufficient quantity of primary T cells, and their insufficient expansion and function. CAR-T cells prepared from allogeneic sources (allo-CAR-Ts) can be an alternative option to overcome these obstacles. Recently, several allo-CAR-Ts have entered into the early clinical trials. Despite their promising preclinical and clinical results, there are two main barriers, including graft-versus-host disease (GvHD) and allo-rejection that may decline the safety and efficacy of allo-CAR-Ts in the clinic. The successful development of these products depends on the starter cell source, the gene editing method, and the ability to escape immune rejection and prevent GvHD. Here, we summarize the gene editing technologies and the potential of various cell sources for developing allo-CAR-Ts and highlight their advantages for the treatment of hematological malignancies. We also describe preclinical and clinical data focusing on allo-CAR-T therapy in blood malignancies and discuss challenges and future perspectives of allo-CAR-Ts for therapeutic applications.

Exosomes-based immunotherapy for cancer: Effective components in the naïve and engineered forms

Today, cancer treatment is one of the main challenges for researchers. The main cause of tumor cell formation is mutations that lead to uncontrolled proliferation and inhibition of apoptosis in malignant cells. Tumor cells also create a microenvironment that can suppress the immune system cells' responses through various methods, including producing soluble factors and cell-to-cell communication. After being produced from tumor cells, exosomes can also affect the functions of other cells in this microenvironment. Various studies have shown that exosomes from different sources, including tumor cells and immune cells, can be used to treat cancers due to their characteristics. Since tumor cells are rich sources of various types of tumor peptides, they can induce anti-tumor responses. Immune cells also produce exosomes that mimic the functions of their cells of origin, such that exosomes derived from NK cells and CTLs can directly lead to their apoptosis after merging with tumor cells. However, many researchers have pointed out that naïve exosomes have a limited therapeutic function, and their therapeutic potential can be increased by manipulating and engineering them. There are various methods to modify exosomes and improve their therapeutic potential. In general, these methods are divided into two parts, which include changing the cell of origin of the exosome and encapsulating the exosome to carry different drugs. In this review, we will discuss the studies on the therapeutic use of naive and engineered exosomes and provide an update on new studies in this field.

Tri-specific killer engager: unleashing multi-synergic power against cancer

Cancer continues to be a global health concern, necessitating innovative solutions for treatment. Tri-specific killer engagers (TriKEs) have emerged as a promising class of immunotherapeutic agents, offering a multifaceted approach to cancer treatment. TriKEs simultaneously engage and activate natural killer (NK) cells while specifically targeting cancer cells, representing an outstanding advancement in immunotherapy. This review explores the generation and mechanisms of TriKEs, highlighting their advantages over other immunotherapies and discussing their potential impact on clinical trials and cancer treatment. TriKEs are composed of three distinct domains, primarily antibody-derived building blocks, linked together by short amino acid sequences. They incorporate critical elements, anti-cluster of differentiation 16 (CD16) and interleukin-15 (IL-15), which activate and enhance NK cell function, together with specific antibody to target each cancer. TriKEs exhibit remarkable potential in preclinical and early clinical studies across various cancer types, making them a versatile tool in cancer immunotherapy. Comparative analyses with other immunotherapies, such as chimeric antigen receptor-T (CAR-T) cell therapy, immune checkpoint inhibitors (ICIs), cytokine therapies, and monoclonal antibodies (mAbs), reveal the unique advantages of TriKEs. They offer a safer pathway for immunotherapy by targeting cancer cells without hyperactivating T cells, reducing off-target effects and complications. The future of TriKEs involves addressing challenges related to dosing, tumor-associated antigen (TAA) expression, and NK cell suppression. Researchers are exploring innovative dosing strategies, enhancing specificity through tumor-specific antigens (TSAs), and combining TriKEs with other therapies for increased efficacy.

Recent advances in biomaterial designs for assisting CAR-T cell therapy towards potential solid tumor treatment

Chimeric antigen receptor T (CAR-T) cells have shown promising outcomes in the treatment of hematologic malignancies. However, CAR-T cell therapy in solid tumor treatment has been significantly hindered, due to the complex manufacturing process, difficulties in proliferation and infiltration, lack of precision, or poor visualization ability. Fortunately, recent reports have shown that functional biomaterial designs such as nanoparticles, polymers, hydrogels, or implantable scaffolds might have potential to address the above challenges. In this review, we aim to summarize the recent advances in the designs of functional biomaterials for assisting CAR-T cell therapy for potential solid tumor treatments. Firstly, by enabling efficient CAR gene delivery in vivo and in vitro, functional biomaterials can streamline the difficult process of CAR-T cell therapy manufacturing. Secondly, they might also serve as carriers for drugs and bioactive molecules, promoting the proliferation and infiltration of CAR-T cells. Furthermore, a number of functional biomaterial designs with immunomodulatory properties might modulate the tumor microenvironment, which could provide a platform for combination therapies or improve the efficacy of CAR-T cell therapy through synergistic therapeutic effects. Last but not least, the current challenges with biomaterials-based CAR-T therapies will also be discussed, which might be helpful for the future design of CAR-T therapy in solid tumor treatment.

Forks in the road for CAR T and CAR NK cell cancer therapies

The advent of chimeric antigen receptor (CAR) T cell therapy has resulted in unprecedented long-term clearance of relapse/refractory hematological malignancies in both pediatric and adult patients. However, severe toxicities, such as cytokine release syndrome and neurotoxicity, associated with CAR T cells affect therapeutic utility; and treatment efficacies for solid tumors are still not impressive. As a result, engineering strategies that modify other immune cell types, especially natural killer (NK) cells have arisen. Owing to both CAR-dependent and CAR-independent (innate immune-mediated) antitumor killing capacity, major histocompatibility complex-independent cytotoxicity, reduced risk of alloreactivity and lack of major CAR T cell toxicities, CAR NK cells constitute one of the promising next-generation CAR immune cells that are also amenable as 'off-the-shelf' therapeutics. In this Review, we compare CAR T and CAR NK cell therapies, with particular focus on immunological synapses, engineering strategies and challenges.

Nanobodies: A Game-Changer in Cell-Mediated Immunotherapy for Cancer

Nanobodies are small, single-domain antibodies that have emerged as a promising tool in cancer immunotherapy. These molecules can target specific antigens on cancer cells and trigger an immune response against them. In this mini-review article, we highlight the potential of nanobodies in cell-mediated immunotherapy for cancer treatment. We discuss the advantages of nanobodies over conventional antibodies, their ability to penetrate solid tumors, and their potential to enhance the efficacy of other immunotherapeutic agents. We also provide an overview of recent preclinical and clinical studies that have demonstrated the effectiveness of nanobody-based immunotherapy in various types of cancer.

Nanobody-based trispecific T cell engager (Nb-TriTE) enhances therapeutic efficacy by overcoming tumor-mediated immunosuppression

BACKGROUND

T cell engagers (TCEs) have been established as an emerging modality for hematologic malignancies, but solid tumors remain refractory. However, the upregulation of programmed cell death 1 (PD-1) is correlated with T cell dysfunction that confer tumor-mediated immunosuppression. Developing a novel nanobody-based trispecific T cell engager (Nb-TriTE) would be a potential strategy to improve therapeutic efficacy.

METHODS

Given the therapeutic potential of nanobodies (Nbs), we first screened Nb targeting fibroblast activation protein (FAP) and successfully generated a Nb-based bispecific T cell engager (Nb-BiTE) targeting FAP. Then, we developed a Nb-TriTE by fusing an anti-PD-1 Nb to the Nb-BiTE. The biological activity and antitumor efficacy of the Nb-TriTE were evaluated in vitro and in both cell line-derived and patient-derived xenograft mouse models.

RESULTS

We had for the first time successfully selected a FAP Nb for the generation of novel Nb-BiTE and Nb-TriTE, which showed good binding ability to their targets. Nb-TriTE not only induced robust tumor antigen-specific killing, potent T cell activation and enhanced T cell function in vitro, but also suppressed tumor growth, improved survival and mediated more T cell infiltration than Nb-BiTE in mouse models of different solid tumors without toxicity.

CONCLUSIONS

This novel Nb-TriTE provides a promising and universal platform to overcome tumor-mediated immunosuppression and improve patient outcomes in the future.

A PD-L1xCD3 bispecific nanobody as a novel T-cell engager in treating PD-L1 overexpression melanoma

The development of Immune checkpoint blockade(ICB) therapy and BRAF- and MEK-targeted therapies has reshaped the survival outcomes of the patients with advanced melanoma. PD-1/PD-L1 blockade was an approved strategy in melanoma treatment. Here we design a PD-L1 xCD3 nanobody as a novel bispecific T cell engager (BiTE) in treating PD-L1 overexpression melanoma. BiTE PD-L1×CD3 Nb was predicted to bind near a large acidic surface on CD3-ε similar to UCHT1-scFv antibody based on alpha-fold and molecular docking. BiTE PD-L1×CD3 Nb and anti-CD3 Nb retained the ability to activate T cells to produce TNF-α and IFN-γ in a dose-dependent manner. The IC50 value of BiTE PD-L1×CD3 Nb was 4.208μg/mL. BiTE PD-L1×CD3 Nb showed obvious cytotoxic activity on both A375WT and A375PD-L1 related to PD-L1 expression level.

Chimeric antigen receptor-natural killer cells: a promising sword against insidious tumor cells

Natural killer (NK) cells are a critical component of innate immunity, particularly in initial cancer recognition and inhibition of additional tumor growth or metastasis propagation. NK cells recognize transformed cells without prior sensitization via stimulatory receptors and rapidly eradicate them. However, the protective tumor microenvironment facilitates tumor escaping via induction of an exhaustion state in immune cells, including NK cells. Hence, genetic manipulation of NK cells for specific identification of tumor-associated antigens or a more robust response against tumor cells is a promising strategy for NK cells' tumoricidal augmentation. Regarding the remarkable achievement of engineered CAR-T cells in treating hematologic malignancies, there is evolving interest in CAR-NK cell recruitment in cancer immunotherapy. Innate functionality of NK cells, higher safety, superior in vivo maintenance, and the off-the-shelf potential move CAR-NK-based therapy superior to CAR-T cells treatment. In this review, we have comprehensively discussed the recent genetic manipulations of CAR-NK cell manufacturing regarding different domains of CAR constructs and their following delivery systems into diverse sources of NK cells. Then highlight the preclinical and clinical investigations of CAR-NK cells and examine the current challenges and prospects as an optimistic remedy in cancer immunotherapy.

Induced Pluripotent Stem Cell-Derived Chimeric Antigen Receptor T Cells: The Intersection of Stem Cells and Immunotherapy

Chimeric antigen receptor (CAR) T cell therapy is a promising cell-based immunotherapy applicable to various cancers. High cost of production, immune rejection, heterogeneity of cell product, limited cell source, limited expandability, and relatively long production time have created the need to achieve a universal allogeneic CAR-T cell product for "off-the-shelf" application. Since the innovation of induced pluripotent stem cells (iPSCs) by Yamanaka et al., extensive efforts have been made to prepare an unlimited cell source for regenerative medicine, that is, immunotherapy. In the autologous grafting approach, iPSCs prepare the desired cell source for generating autologous CAR-T cells through more accessible and available sources. In addition, generating iPSC-derived CAR-T cells is a promising approach to achieving a suitable source for producing an allogeneic CAR-T cell product. In brief, the first step is reprogramming somatic cells (accessible from peripheral blood, skin, etc.) to iPSCs. In the next step, CAR expression and T cell lineage differentiation should be applied in different arrangements. In addition, in an allogeneic manner, human leukocyte antigen/T cell receptor (TCR) deficiency should be applied in iPSC colonies. The allogeneic iPSC-derived CAR-T cell experiments showed that simultaneous performance of HLA/TCR deficiency, CAR expression, and T cell lineage differentiation could bring the production to the highest efficacy in generating allogeneic iPSC-derived CAR-T cells.

Checkpoint blockade meets gene therapy: Opportunities to improve response and reduce toxicity

Immune checkpoint inhibitors (ICIs) based on monoclonal antibodies represent a breakthrough for the treatment of cancer. However, their efficacy varies among tumor types and patients, and they can lead to adverse effects due to on-target/off-tumor activity, since they are administered systemically at high doses. An alternative and attractive approach for the delivery of ICIs is the use of gene therapy vectors able to express them in vivo. This review focuses on the most recent studies using viral vectors able to express ICIs locally or systemically in preclinical models of cancer. These vectors include non-replicating viruses, oncolytic viruses able to propagate specifically in tumor cells and destroy them, and self-amplifying RNA vectors, armed with different formats of antibodies against immune checkpoints. Non-replicating vectors usually lead to long-term ICI expression, potentially eliminating the need for repeated administration. Vectors with replication capacity, although they have a shorter window of expression, can induce inflammation which enhances the antitumor effect. Finally, these engineered vectors can be used in combination with other immunostimulatory molecules or with CAR-T cells, further boosting the antitumor immune responses.

Nanomaterials in tumor immunotherapy: new strategies and challenges

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

Smaller size packs a stronger punch - Recent advances in small antibody fragments targeting tumour-associated carbohydrate antigens

Attached to proteins, lipids, or forming long, complex chains, glycans represent the most versatile post-translational modification in nature and surround all human cells. Unique glycan structures are monitored by the immune system and differentiate self from non-self and healthy from malignant cells. Aberrant glycosylations, termed tumour-associated carbohydrate antigens (TACAs), are a hallmark of cancer and are correlated with all aspects of cancer biology. Therefore, TACAs represent attractive targets for monoclonal antibodies for cancer diagnosis and therapy. However, due to the thick and dense glycocalyx as well as the tumour micro-environment, conventional antibodies often suffer from restricted access and limited effectiveness in vivo. To overcome this issue, many small antibody fragments have come forth, showing similar affinity with better efficiency than their full-length counterparts. Here we review small antibody fragments against specific glycans on tumour cells and highlight their advantages over conventional antibodies.

Natural killer cell epigenetic reprogramming in tumors and potential for cancer immunotherapy

Natural killer (NK) cells are critical members of the innate lymphoid cell population and have a pivotal role in cancer eradication. NK cell maturation, development and function are tightly regulated by epigenetic modifications, which can also be recruited for cancer propagation and immune escape. NK cells have the potential to be activated against tumors through several epigenetic regulators. Given that epigenetic changes are inducible and reversible, focusing on aberrant epigenetic regulations recruited by tumor cells provides a tremendous opportunity for cancer treatment. This review presents a comprehensive picture of NK cell normal epigenetic regulation and cancer-driven epigenetic modifications. From our perspective, a better understanding of epigenetic regulators that can edit and revise NK cells' activity is a promising avenue for NK cell-based therapy in cancer management.