Strategy For Cancer Immunotherapy Research Articles

Targeting STAT3 in tumor-associated antigen-presenting cells as a strategy for kidney and bladder cancer immunotherapy.

Immune checkpoint blockade (ICB) improved clinical outcomes in renal and bladder cancer patients, but the response rates remain limited especially in metastatic disease. While STAT3 transcription factor is well-known master regulator of tumor immune evasion, little is known about the role of STAT3 in the resistance of renal or bladder cancers to immunotherapy. To better understand immune alterations associated with ICB resistance, we assessed blood biomarkers in renal cancer patients classified as responders or non-responders to first line nivolumab/ipilimumab immunotherapy. We observed that non-responders showed elevated levels of proinflammatory mediators, such as IL-1RA, IL-6, IL-8 and to lesser extent IL-10, which are associated with STAT3 activation and tumor immunosuppression. In addition, we found STAT3 activation primarily in circulating myeloid immune cells such as tolerogenic MDSCs. To assess whether STAT3 inhibition within these cell subsets can promote antitumor immune responses and/or enhance sensitivity to ICB in vivo, we used an original antisense oligonucleotide (ASO) strategy for myeloid-cell selective STAT3 knockdown (CpG-STAT3ASO). Our results in syngeneic models of renal and bladder cancers in mice demonstrated potent antitumor activity of CpG-STAT3ASO alone in contrast to PD1 blockade alone in both models. The CpG-STAT3ASO/anti-PD1 combination improved therapeutic efficacy especially against bladder tumors. Therapeutic efficacy correlated with activation of dendritic cells (DCs) and M1 macrophages in the tumor microenvironment, reduced percentages of regulatory T cells (Tregs) and the expansion of CD8 T cells in both tumor models. Our study underscores the potential of using myeloid-cell targeted CpG-STAT3 inhibitors for genitourinary cancer therapy to disrupt tolerogenic signaling, restore immune cell activity and sensitivity to immune checkpoint inhibitors and/or T cell-based immunotherapies.

Cancer cell membrane proteins-encapsulated nanovaccine enhances cancer immunotherapy and prevention by provoking antigen-specific cellular immunity via the dendritic cell-targeted delivery

Cancer nanovaccines offer a promising strategy for fighting against tumors, however, the engineering of cancer nanovaccines that can be easily fabricated with tanglesome cancer cell-derived antigens and elicit an adequately strong tumor-specific cellular immunity remains challenging. Herein, metal-phenolic networks (MPNs) are used as an antigen delivery platform to prepare the mannose-modified MPNs nanovaccine loaded with ovalbumin (OVA) and the immunoadjuvant CpG oligodeoxynucleotide (MMOC) through the facile self-assembly. When the model antigen OVA is substituted with cancer cell membrane proteins (CCMPs), the nanovaccine is called MMCC. MMOC markedly activates dendritic cells (DCs) via the mannose-mediated endocytosis and efficiently promotes the antigen cross-presentation, thus inspiring a robust antigen-specific CD8+ T cell response as well as immune memory effect in vivo. Consequently, MMOC exhibits admirable therapeutic and preventive results on E.G7-OVA tumors. Moreover, the combination use of MMCC with anti-PD1 significantly inhibits the growth of 4T1 tumors by strengthening the cellular immunity and decreasing the proportion of regulatory T cells (Tregs). The survival rate of 4T1 tumor-bearing mice in the prophylaxis assay is maintained at 100 % by MMCC over 42 days. Altogether, this study affords a universal and effective nanovaccine preparation strategy for cancer immunotherapy and prevention.

Computational discovery of co-expressed antigens as dual targeting candidates for cancer therapy through bulk, single-cell, and spatial transcriptomics

Abstract Motivation Bispecific antibodies (bsAbs) that bind to two distinct surface antigens on cancer cells are emerging as an appealing therapeutic strategy in cancer immunotherapy. However, considering the vast number of surface proteins, experimental identification of potential antigen pairs that are selectively expressed in cancer cells and not in normal cells is both costly and time-consuming. Recent studies have utilized large bulk RNA-seq databases to propose bispecific targets for various cancers. However, co-expressed pairs derived from bulk RNA-seq do not necessarily indicate true co-expression of both markers in malignant cells. Single-cell RNA-seq (scRNA-seq) can circumvent this issue but the issues in low coverage of transcripts impede the large-scale characterization of co-expressed pairs. Results We present a computational pipeline for bsAbs target identification which combines the advantages of bulk and scRNA-seq while minimizing the issues associated with using these approaches separately. We select hepatocellular carcinoma (HCC) as a case study to demonstrate the utility of the approach. First, using the bulk RNA-seq samples in the OCTAD database, we identified target pairs that most distinctly differentiate tumor cases from healthy controls. Next, we confirmed our findings on the scRNA-seq database comprising 39 361 healthy cells from vital organs and 18 000 cells from HCC tumors. The top pair was GPC3–MUC13, where both genes are co-expressed on the surface of over 30% of malignant hepatocytes and have very low expression in other cells. Finally, we leveraged the emerging spatial transcriptomic to validate the co-expressed pair in situ. Availability and implementation A standalone R package (https://github.com/Bin-Chen-Lab/bsAbsFinder).

Emerging mechanisms and implications of cGAS-STING signaling in cancer immunotherapy strategies.

The intricate interplay between the human immune system and cancer development underscores the central role of immunotherapy in cancer treatment. Within this landscape, the innate immune system, a critical sentinel protecting against tumor incursion, is a key player. The cyclic GMP-AMP synthase (cGAS) and stimulator of interferon genes (STING) pathway has been found to be a linchpin of innate immunity: activation of this signaling pathway orchestrates the production of type I interferon (IFN-α/β), thus fostering the maturation, differentiation, and mobilization of immune effectors in the tumor microenvironment. Furthermore, STING activation facilitates the release and presentation of tumor antigens, and therefore is an attractive target for cancer immunotherapy. Current strategies to activate the STING pathway, including use of pharmacological agonists, have made substantial advancements, particularly when combined with immune checkpoint inhibitors. These approaches have shown promise in preclinical and clinical settings, by enhancing patient survival rates. This review describes the evolving understanding of the cGAS-STING pathway's involvement in tumor biology and therapy. Moreover, this review explores classical and non-classical STING agonists, providing insights into their mechanisms of action and potential for optimizing immunotherapy strategies. Despite challenges and complexities, the cGAS-STING pathway, a promising avenue for enhancing cancer treatment efficacy, has the potential to revolutionize patient outcomes.

CRISPR-Cas9 Unleashed: Gene-Slicing Adventures in the Cancer Battlefield

<p class="MsoNormal" style="text-align: justify;"><span lang="EN-US">Cancer, a global health menace, continues to pose significant challenges in terms of incidence and mortality, necessitating innovative therapeutic strategies. Despite existing treatments, the limitations persist, prompting a quest for novel approaches. The emergence of immunotherapy marked a transformative era in solid tumor treatments, yet its efficacy is constrained by adverse effects. Concurrently, the integration of advanced technologies into cancer treatment explores the vast potential residing at the molecular level through gene analysis and manipulation. This review articulates the role of state-of-the-art genome editing technology, notably clustered regularly interspaced short palindromic repeats (CRISPR-Cas9), in overcoming the constraints of immunotherapy for cancers. Unveiling the intricacies of CRISPR-Cas9-mediated genome editing, the review introduces the formidable CRISPR toolbox. A spotlight is cast on the transformative impact of CRISPR-induced double-strand breaks (DSBs) on cancer immunotherapy, encompassing knockout and knock-in strategies. The utilization of CRISPR/Cas9 technology in pre-clinical cancer research has demonstrated notable success; however, its transition to the clinical setting remains in the nascent stages of development. This review aims to elucidate the fundamental aspects of CRISPR technology and offer a comprehensive survey of its existing applications while outlining its prospective role in the realm of cancer therapies. Through an exploration of CRISPR's mechanisms, current applications, and anticipated future potentials, this review provides valuable insights into the evolving landscape of CRISPR-based cancer treatment strategies.</span></p>

Immunoreactive Microenvironment Modulator GBP5 Suppresses Ovarian Cancer Progression by Inducing Canonical Pyroptosis.

Ovarian cancer has the highest mortality among gynecological malignancies, and exploring effective strategies to reverse the immunosuppressive tumor microenvironment in patients remains a pressing scientific challenge. In this study, we identified a pyroptosis-related protective factor, GBP5, which significantly inhibits the growth of ovarian cancer cells and patient-derived ovarian cancer organoids, impeding the invasion and migration of ovarian cancer cells. Results of immunohistochemistry and external single-cell data verification were consistent. Further research confirmed that GBP5 in ovarian cancer cell can induce canonical pyroptosis through JAK2/STAT1 pathway, thereby restraining the progression of ovarian cancer. Interestingly, in this study, we also discovered that ovarian cancer cells with high GBP5 expression exhibit increased expressions of CXCL9/10/11 in a co-culture assay. Subsequent immune cell infiltration analyses revealed the remodeling of immunosuppressive microenvironment in ovarian cancer patients, characterized by increased infiltration and polarization of M1 macrophages. External immunotherapy database analysis showed profound potential for the application of GBP5 in immunotherapy strategies for ovarian cancer. Overall, our study demonstrates that the protective factor GBP5 significantly inhibits ovarian cancer progression, triggering canonical pyroptosis through the JAK2-STAT1 pathway. Driven by its pro-inflammatory nature, it can also enhance M1 macrophages polarization and reverse immunosuppressive microenvironment, thus providing new insights for ovarian cancer treatment.

Strategies for Small Extracellular Vesicle-Based Cancer Immunotherapy.

Extracellular vesicles (EVs) are lipid bilayer-enclosed vesicles released by cells. EVs encapsulate proteins and nucleic acids of their parental cell and efficiently deliver the cargo to recipient cells. These vesicles act as mediators of intercellular communication and thus play a crucial role in various physiological and pathological processes. Moreover, EVs hold promise for clinical use. They have been explored as drug delivery vehicles, therapeutic agents, and targets for disease diagnosis. In the landscape of cancer research, while strides have been made in EV-focused cancer physiopathology, liquid biopsy, and drug delivery, the exploration of EVs as immunotherapeutic agents may not have seen substantial progress to date. Despite promising findings reported in cell and animal studies, the clinical translation of EV-based cancer immunotherapeutics encounters challenges. Here, we review the existing strategies used in EV-based cancer immunotherapy, aiming to propel the development of this emerging yet crucial field.

A phosphatase-like nanomaterial promotes autophagy and reprograms macrophages for cancer immunotherapy.

Macrophages are plastic and play a key role in the maintenance of tissue homeostasis. In cancer progression, macrophages also take part in all processes, from initiation to progression, to final tumor metastasis. Although energy deprivation and autophagy are widely used for cancer therapy, most of these strategies do not target macrophages, resulting in undesired effects and unsatisfactory outcomes for cancer immunotherapy. Herein, we developed a lanthanum nickel oxide (LNO) nanozyme with phosphatase-like activity for ATP hydrolysis. Meanwhile, the autophagy of macrophages induced by LNO promotes the polarization of macrophages from M2-like macrophages (M2) to M1-like macrophages (M1) and reduces tumor-associated macrophages in tumor-bearing mice, exhibiting the capability of killing tumor-associated macrophages and antitumor effects in vivo. Furthermore, pre-coating the surface of LNO with a myeloid cell membrane significantly enhanced antitumor immunity. Our findings demonstrate that phosphatase-like nanozyme LNO can specifically induce macrophage autophagy, which improves therapeutic efficacy and offers valuable strategies for cancer immunotherapy.

Targeting the CD24-Siglec10 Axis: A Potential Strategy for Cancer Immunotherapy

Abstract CD24, also known as heat-stable protein, is a highly glycosylated glycosylphosphatidylinositol junction membrane protein. CD24 specifically binds sialic-acid-binding Ig-like lectin 10 (Siglec10) on macrophages and serves as a “don’t eat me” signal, thus blocking the phagocytosis of tumor cells by macrophages and triggering tumor immune escape. Blocking the CD24-Siglec10 axis to reprogram the tumor immune microenvironment is a current research hotspot in cancer immunotherapy. Targeting the CD24-Siglec10 axis has received widespread attention, because of the high expression of CD24 on a variety of tumor cells and absence of blood toxicity. Targeting the CD24-Siglec10 axis as a cancer immunotherapy has shown favorable results and progress in preclinical studies. In this review, we summarize the discovery and functions of the CD24-Siglec10 axis, and review the roles and effects of this axis as a novel immune checkpoint in cancer immunotherapy. We also highlight recent advances in nanoparticle-mediated treatments targeting the CD24-Siglec10 axis for enhancing cancer immunotherapy.

RCAd-LTH-shPD-L1, a double-gene recombinant oncolytic adenovirus with enhanced antitumor immunity, increases lymphocyte infiltration and reshapes the tumor microenvironment

BackgroundWith the successful development of modern immunotherapy, immune checkpoint inhibitors (ICIs) are currently considered potential therapeutic options for patients with cancer. However, the therapeutic potential of ICIs in human cancer...

Role of UFMylation in tumorigenesis and cancer immunotherapy.

Protein post-translational modifications (PTMs) represent a crucial aspect of cellular regulation, occurring after protein synthesis from mRNA. These modifications, which include phosphorylation, ubiquitination, acetylation, methylation, glycosylation, Sumoylation, and palmitoylation, play pivotal roles in modulating protein function. PTMs influence protein localization, stability, and interactions, thereby orchestrating a variety of cellular processes in response to internal and external stimuli. Dysregulation of PTMs is linked to a spectrum of diseases, such as cancer, inflammatory diseases, and neurodegenerative disorders. UFMylation, a type of PTMs, has recently gained prominence for its regulatory role in numerous cellular processes, including protein stability, response to cellular stress, and key signaling pathways influencing cellular functions. This review highlights the crucial function of UFMylation in the development and progression of tumors, underscoring its potential as a therapeutic target. Moreover, we discuss the pivotal role of UFMylation in tumorigenesis and malignant progression, and explore its impact on cancer immunotherapy. The article aims to provide a comprehensive overview of biological functions of UFMylation and propose how targeting UFMylation could enhance the effectiveness of cancer immunotherapy strategies.

Identification of novel immuno-oncology compounds as VISTA-inhibitors for cancer therapy: A computational approach integrating virtual screening and molecular dynamics simulation

The landscape of cancer treatment has witnessed a paradigm shift with the emergence of immunotherapy, particularly the inhibition of immune checkpoints like programmed cell death protein 1 (PD-1) and its ligand PD-L1. While these therapies have revolutionized cancer treatment, a substantial proportion of patients still fail to respond, highlighting the need to explore alternative immune checkpoints. V-domain immunoglobulin suppressor of T cell activation (VISTA), a member of the B7 family, has orchestrated significant attention. Abundantly expressed in tumor-infiltrating lymphocytes, VISTA's role in regulating immune responses, especially in breast cancer, hints at its potential as a linchpin in breast cancer immunotherapy. This research focuses on molecular docking simulations of a diverse array of immuno-oncology compounds to identify potential VISTA inhibitors. Three promising candidates (Compound_6784, Compound_14718, and Compound_34839) exhibited favorable binding affinities with VISTA, forming key interactions with critical amino acid residues. ADME-Tox profiling revealed these compounds to be highly druggable, displaying minimal toxicity risks, making them suitable for clinical trials and drug development. Additionally, molecular dynamics simulations provided insights into the structural dynamics of these compounds. The metrics underline the superior stability of Compound_14718, making it the most promising candidate for further research and drug development. This research lays a robust foundation for the development of novel immunotherapies targeting VISTA in cancer treatment. The identified compounds present promising candidates for further investigation and drug development, offering hope for improved cancer immunotherapy strategies.

Spontaneous regression of cancer: a review of cases reported in Indian literature

Spontaneous regression of tumors is an exceptional response in the absence of standard treatment for the disease. The associated mechanisms are not completely understood, however immune modulation has been indicated to be the most probable process for spontaneous regression. Summarizing and analyzing the available information of these cases may aid in developing effective and safe therapeutic modalities for cancer. This review investigates the spontaneous regression cases reported in India during the period of 1988 to 2022. We conducted an online search (Google and Pubmed) using the keywords “spontaneous regression, cancer, India” for reports from India. All reports in the relevant literature were investigated for the criteria of spontaneous regression by Everson and Cole. 18 cases were defined as spontaneous regression and are reviewed in this article. The available information regarding patient demography, diagnosis, treatments and follow-up has been summarized. Squamous cell carcinoma is the most common type among 18 cases. 12 cases showed complete regression of tumor whereas 5 of them were partially regressed. Only 4 cases received chemotherapy and rest were not treated with any conventional anticancer treatment. An attempt has been made to delineate the mechanisms for SR proposed by the investigators. Acquiring data of more cases and more detailed information will definitely help us understand the mechanism of regression, providing an opportunity to improve cancer immunotherapy strategies.

1,5-Disubstituted tetrazoles as PD-1/PD-L1 antagonists.

The progress in cancer survival and treatment has witnessed a remarkable transformation through the innovative approach of targeting the inhibitory immune checkpoint protein PD-1/PD-L1 complex by mAbs, e.g. pembrolizumab (Keytruda). While generating 17.2 billion U.S. dollars in revenue in 2021, the true significance of these developments lies in their ability to enhance cancer patient outcomes. Despite the proven efficacy of mAbs in inhibiting the PD-1/PD-L1 signaling pathways, they face significant challenges, including limited response rates, high production costs, missing oral bioavailability, and extended half-lives that can lead to immune-related adverse effects. A promising alternative approach involves the use of small molecules acting as PD-1/PD-L1 antagonists to stimulate PD-L1 dimerization. However, the precise mechanisms of action of these molecules remain partially understood, posing challenges to their development. In this context, our research focuses on the creation of a novel scaffold based on the Ugi tetrazole four-component reaction (UT-4CR) to develop low-molecular-weight inhibitors of PD-L1. Employing structure-based methods, we synthesized a library of small compounds using biphenyl vinyl isocyanide, leading to the discovery of a structure-activity relationship among 1,5-disubstituted tetrazole-based inhibitors. Supported by a cocrystal structure with PD-L1, these inhibitors underwent biophysical testing, including HTRF and protein NMR experiments, resulting in the identification of potent candidates with sub-micromolar PD-L1 affinities. This finding opens opportunities to the further development of a new class of PD-L1 antagonists, holding promise for improved cancer immunotherapy strategies.

In vitro co-culture models for studying organoids-macrophages interaction: the golden technology of cancer immunotherapy.

Macrophages, as the largest immune cell group in tumour tissues, play a crucial role in influencing various malignant behaviours of tumour cells and tumour immune evasion. As the research on macrophages and cancer immunotherapy develops, the importance of appropriate research models becomes increasingly evident. The development of organoids has bridged the gap between traditional two-dimensional (2D) cultures and animal experiments. Recent studies have demonstrated that organoids exhibit similar physiological characteristics to the source tissue and closely resemble the in vivo genome and molecular markers of the source tissue or organ. However, organoids still lack an immune component. Developing a co-culture model of organoids and macrophages is crucial for studying the interaction and mechanisms between tumour cells and macrophages. This paper presents an overview of the establishment of co-culture models, the current research status of organoid macrophage interactions, and the current status of immunotherapy. In addition, the application prospects and shortcomings of the model are explained. Ultimately, it is hoped that the co-culture model will offer a preclinical testing platform for maximising a precise cancer immunotherapy strategy.

Repolarizing Tumor-Associated Macrophages and inducing immunogenic cell Death: A targeted liposomal strategy to boost cancer immunotherapy

Cancer immunotherapy has shown promise in treating various malignancies. However, the presence of an immunosuppressive tumor microenvironment (TME) triggered by M2 tumor-associated macrophages (TAMs) and the limited tumor cell antigenicity have hindered its broader application. To address these challenges, we developed DOX/R837@ManL, a liposome loaded with imiquimod (R837) and doxorubicin (DOX), modified with mannose-polyethylene glycol (Man-PEG). DOX/R837@ManL employed a mannose receptor (MRC1)-mediated targeting strategy, allowing it to accumulate selectively at M2 Tumor associated macrophages (TAMs) and tumor sites. R837, an immune adjuvant, promoted the conversion of immunosuppressive M2 TAMs into immunostimulatory M1 TAMs, and reshaped the immunosuppressive TME. Simultaneously, DOX release induced immunogenic cell death (ICD) in tumor cells and enhanced tumor cell antigenicity by promoting dendritic cells (DCs) maturation. Through targeted delivery, the synergistic action of R837 and DOX activated innate immunity and coordinated adaptive immunity, enhancing immunotherapy efficacy. In vivo experiments have demonstrated that DOX/R837@ManL effectively eliminated primary tumors and lung metastases, while also preventing tumor recurrence post-surgery. These findings highlighted the potential of DOX/R837@ManL as a promising strategy for cancer immunotherapy.

Ex Vivo Surface Decoration of Phenylboronic Acid onto Natural Killer Cells for Sialic Acid-Mediated Versatile Cancer Cell Targeting.

Phenylboronic acid (PBA) has been highly acknowledged as a significant cancer recognition moiety in sialic acid-overexpressing cancer cells. In this investigation, lipid-mediated biomaterial integrated PBA molecules onto the surface of natural killer (NK) cells to make a receptor-mediated immune cell therapeutic module. Therefore, a 1,2-distearoyl-sn-glycero-3-phosphorylethanolamine (DSPE) lipid-conjugated di-PEG-PBA (DSPEPEG-di(PEG-PBA) biomaterial was synthesized. The DSPEPEG-di(PEG-PBA) biomaterial exhibited a high affinity for sialic acid (SA), confirmed by fluorescence spectroscopy at pH 6.5 and 7.4. DSPEPEG-di(PEG-PBA) was successfully anchored onto NK cell surfaces (PBA-NK), and this biomaterial maintains intrinsic properties such as viability, ligand availability (FasL & TRAIL), and cytokine secretion response to LPS. The anticancer efficacy of PBA-NK cells was evaluated against 2D cancer cells (MDA-MB-231, HepG2, and HCT-116) and 3D tumor spheroids of MDA-MB-231 cells. PBA-NK cells exhibited greatly enhanced anticancer effects against SA-overexpressing cancer cells. Thus, PBA-NK cells represent a new anticancer strategy for cancer immunotherapy.

Engineered polymer‐based scaffold as an implantable therapeutic vaccine against melanoma

AbstractAlthough tumor‐antigen‐based therapeutic cancer vaccines are a potential cancer immunotherapy strategy, recent clinical trials show low efficacy for multiple reasons. One method that has been recently investigated to improve the efficacy of therapeutic cancer vaccines is the development of implantable vaccines for sustained delivery of antigens and CD8 T cell activation. Here, we optimized the composition for an implantable vaccine scaffold composed of alginate, polyvinyl alcohol, and poly(methyl vinyl ether‐ alt‐maleic anhydride) loaded with tumor antigens. Considering the adjuvant property of aluminum compounds, aluminum ion was used to crosslink alginate in the scaffold. The scaffold showed an effective antigen incorporation efficiency of 90.34 ± 0.55% using ovalbumin as the model antigen and 89.67 ± 2.8% using B16‐F10 cell lysate. SEM analysis of the scaffold showed pore size ranging from 5 to 10 μm. Cell viability analysis using mouse RAW 264.7 macrophages proved the cytocompatibility of the scaffold. In vitro antigen release studies using ovalbumin showed 8.42% release for a period of 14 days. In vivo antitumor analysis carried out in subcutaneous mouse B16‐F10 melanoma model demonstrated that the scaffold vaccine reduced the rate of tumor growth and improved survival in tested animals. The median survival time increased from 29 days in untreated animals to 58 days in scaffold vaccine‐implanted animals.

Ansofaxine hydrochloride inhibits tumor growth and enhances Anti-TNFR2 in murine colon cancer model.

Introduction: As psychoneuroimmunology flourishes, there is compelling evidence that depression suppresses the anti-tumor immune response, promotes the progression of cancer, and inhibits the effectiveness of cancer immunotherapy. Recent studies have reported that antidepressants can not only alleviate the depressant condition of cancer patients, but also strengthen the anti-tumor immunity, thus suppressing tumors. Tumor necrosis factor receptor 2 (TNFR2) antagonistic antibodies (Anti-TNFR2) targeting tumor-infiltrating regulatory T cells (Tregs) has achieved great results in preclinical studies, and with a favorable toxicity profile than existing immunotherapies, and is expected to become a new generation of more effective treatment strategies. Understanding the effects of combination therapy with antidepressants and Anti-TNFR2 may help design new strategies for cancer immunotherapy. Methods: We treated CT26, HCT116, MCA38 and SW620 colon cancer cells with fluoxetine (0-50 µM), ansofaxine hydrochloride (0-50 µM) and amitifadine hydrochloride (0-150 µM) to examine their effects on cell proliferation and apoptosis. We explored the antitumor effects of ansofaxine hydrochloride in combination with or without Anti-TNFR in subcutaneously transplanted CT26 cells in tumor-bearing mouse model. Antitumor effects were evaluated by tumor volume. NK cell, M1 macrophage cell, CD4+ T cell, CD8+ T cell, exhausted CD8+ T and regulatory T cell (Tregs) subtypes were measured by flow cytometry. 5-hydroxytryptamine, dopamine and norepinephrine levels were measured by ELISA. Results: Oral antidepression, ansofaxine hydrochloride, enhanced peripheral dopamine levels, promoted CD8+T cell proliferation, promoted intratumoral infiltration of M1 and NK cells, decreased the proportion of tumor-infiltrating exhausted CD8+T cells, and strengthened anti-tumor immunity, thereby inhibiting colon cancer growth. In combination therapy, oral administration of ansofaxine hydrochloride enhanced the efficacy of Anti-TNFR2, and produced long-term tumor control in with syngeneic colorectal tumor-bearing mice, which was attributable to the reduction in tumor-infiltrating Treg quantity and the recovery of CD8+ T cells function. Discussion: In summary, our data reveal the role of ansofaxine hydrochloride in modulating the anti-tumor immunity. Our results support that exhausted CD8+T is an important potential mechanism by which ansofaxine hydrochloride activates anti-tumor immunity and enhances anti-tumor effects of anti-TNFR2.

The current status and future of PD-L1 in liver cancer.

The application of immunotherapy in tumor, especially immune checkpoint inhibitors (ICIs), has played an important role in the treatment of advanced unresectable liver cancer. However, the efficacy of ICIs varies greatly among different patients, which has aroused people's attention to the regulatory mechanism of programmed death ligand-1 (PD-L1) in the immune escape of liver cancer. PD-L1 is regulated by multiple levels and signaling pathways in hepatocellular carcinoma (HCC), including gene variation, epigenetic inheritance, transcriptional regulation, post-transcriptional regulation, and post-translational modification. More studies have also found that the high expression of PD-L1 may be the main factor affecting the immunotherapy of liver cancer. However, what is the difference of PD-L1 expressed by different types of cells in the microenvironment of HCC, and which type of cells expressed PD-L1 determines the effect of tumor immunotherapy remains unclear. Therefore, clarifying the regulatory mechanism of PD-L1 in liver cancer can provide more basis for liver cancer immunotherapy and combined immune treatment strategy. In addition to its well-known role in immune regulation, PD-L1 also plays a role in regulating cancer cell proliferation and promoting drug resistance of tumor cells, which will be reviewed in this paper. In addition, we also summarized the natural products and drugs that regulated the expression of PD-L1 in HCC.