High intensity focused ultrasound (HIFU), also referred to as focused ultrasound surgery (FUS), has garnered recent attention as a non-invasive therapeutic strategy for prostate cancer. It utilizes focused acoustic energy to achieve localized thermal ablation, while also potentially exerting immunomodulatory effects. This review aims to elucidate the mechanisms underlying how HIFU influences tumor-specific immune responses in prostate cancer. These mechanisms include the release of tumor-associated antigens and damage-associated molecular patterns, the activation of innate immune cells, the facilitation of antigen presentation to adaptive immune cells, the enhancement of activation and proliferation of tumor-specific cytotoxic T lymphocytes, and the attenuation of the immunosuppressive tumor microenvironment by reducing the activity of regulatory T cells and myeloid-derived suppressor cells. Both preclinical investigations and emerging clinical data in prostate cancer models highlight HIFU\'s potential to modulate the immune system, as evidenced by increased infiltration of effector immune cells, elevated levels of pro-inflammatory cytokines, and improved responsiveness to immune checkpoint inhibitors. HIFU induces immunogenic cell death, leading to the release of tumor antigens and danger signals that activate dendritic cells and facilitate cross-presentation to cytotoxic T cells. Additionally, FUS ablation reduces immunosuppressive cells and increases infiltration of CD8+ T cells into the tumor, reshaping the tumor microenvironment. By priming the immune system while overcoming immunosuppression, combining FUS with other immunotherapies like checkpoint inhibitors and cancer vaccines holds promise for synergistic anti-tumor effects. Despite challenges in optimizing parameters and identifying suitable patients, FUS represents a novel frontier by modulating the tumor microenvironment and enhancing anti-tumor immunity through a non-invasive approach.

Sarcoma is derived from mesenchymal neoplasms and has numerous subtypes, accounting for 1% of all adult malignancies and 15% of childhood malignancies. The prognosis of metastatic or recurrent sarcoma remains poor. The current study presents two cases of sarcoma enrolled in a phase I dose escalation trial for solid tumor, who had previously failed all standard therapies. These patients were treated with VG161, an immune-stimulating herpes simplex virus type 1 oncolytic virus with payloads of IL-12, IL-15 and IL-15 receptor α unit, and a programmed cell death 1 (PD-1)/PD-1 ligand 1 blocking peptide. Both cases demonstrated stable disease as the best response, accompanied by a noteworthy prolongation of progression-free survival (11.8 months for chondrosarcoma and 11.9 months for soft tissue sarcoma, respectively) at a dose of 2.5×108 PFU/cycle. In addition, the treatment led to the activation of anti-cancer immunity, as evident from cytokine, lymphocyte subset and related pathway analyses of peripheral blood and/or tumor biopsy samples. These promising results suggest that VG161 monotherapy holds promise as an effective treatment for sarcoma and warrants further investigation through clinical trials. The two reported patients were part of a phase I clinical trial conducted and registered on the Australian New Zealand Clinical Trials Registry in Australia (registration no. ACTRN12620000244909; registration date, 26 February, 2020).

The clinical outcome of lymphocytic leukemia (CLL) is quite heterogeneous. The purpose of this observational study was to investigate the clinical merit of measuring plasma galectin-9 and CXCL-13 concentrations as predictors of CLL activity, prognosis, and early indicators of therapeutic response. These biomarkers were compared with other prognostic indicators, progression-free survival (PFS), time to first treatment (TTT), and overall survival (OS) over a follow-up period (4 years). First, plasma galectin-9 and CXCL-13 concentrations were analyzed in CLL patients at the time of diagnosis as well as healthy controls. Compared to controls, CLL patients had significantly higher serum levels of CXCL-13 and galectin-9. Second, we observed that CLL patients with high soluble CXCL-13 and galectin-9 levels had advanced clinical stages, poor prognosis, 17p del, short PFS, short TTT, and therapy resistance. The levels of CXCL-13, β2-microglobulin, LDH, CD38%, and high grade of Rai-stage were all strongly correlated with the galectin-9 levels. Soluble CXCL-13 and galectin-9 had very good specificity and sensitivity in detecting CLL disease progression and high-risk patients with the superiority of galectin-9 over CXCL-13. Although the two biomarkers were equal in prediction of TTT and treatment response, the soluble CXCL13 was superior in prediction of OS. High CXCL-13 and galectin-9 plasma levels upon CLL diagnosis are associated with disease activity, progression, advanced clinical stages, short periods of PFS, short TTT, and unfavorable treatment response.

Dendritic cells (DCs) are professional antigen-presenting cells that play a crucial role in activating naive T cells through presenting antigen information, thereby influencing immunity and anti-cancer responses. Fascin, a 55-kDa actin-bundling protein, is highly expressed in mature DCs and serves as a marker protein for their identification. However, the precise role of fascin in intratumoral DCs remains poorly understood. In this review, we aim to summarize the role of fascin in both normal and intratumoral DCs. In normal DCs, fascin promotes immune effects through facilitating DC maturation and migration. Through targeting intratumoral DCs, fascin inhibitors enhance anti-tumor immune activity. These roles of fascin in different DC populations offer valuable insights for future research in immunotherapy and strategies aimed at improving cancer treatments.

Splicing abnormality resulting from somatic mutations in key splicing factor genes (SFG) has been detected in various cancers. Hence, an in-depth study of splicing factor genes mutations\' impact on pan-cancer is meaningful. This study investigated associations of splicing factor genes mutations with clinical features, tumor progression phenotypes, genomic integrity, anti-tumor immune responses, and immunotherapy response in 12 common cancer types from the TCGA database. Compared to SFG-wildtype cancers, SFG-mutated cancers displayed worse survival prognosis, higher tumor mutation burden and aneuploidy levels, higher expression of immunosuppressive signatures, and higher levels of tumor stemness, proliferation potential, and intratumor heterogeneity (ITH). However, splicing factor genes-mutated cancers showed higher response rates to immune checkpoint inhibitors than splicing factor genes-wildtype cancers in six cancer cohorts. Single-cell data analysis confirmed that splicing factor genes mutations were associated with increased tumor stemness, proliferation capacity, PD-L1 expression, intratumor heterogeneity, and aneuploidy levels. Our data suggest that the mutation in key splicing factor genes correlates with unfavorable clinical outcomes and disease progression, genomic instability, anti-tumor immunosuppression, and increased immunotherapy response in pan-cancer. Thus, the splicing factor genes mutation is an adverse prognostic factor and a positive marker for immunotherapy response in cancer.

Adenosine triphosphate (ATP) represents a danger signal that accumulates in injured tissues, in inflammatory sites, and in the tumor microenvironment. ATP promotes tumor growth but also anti-tumor immune responses notably via the P2X7 receptor. ATP can also be catabolized by CD39 and CD73 ecto-enzymes into immunosuppressive adenosine. P2X7, CD39 and CD73 have attracted much interest in cancer as targets offering the potential to unleash anti-tumor immune responses. These membrane proteins represent novel purinergic checkpoints that can be targeted by small drugs or biologics. Here, we investigated nanobody-based biologics targeting mainly P2X7, but also CD73, alone or in combination therapies. Blocking P2X7 inhibited tumor growth and improved survival of mice in cancer models that express P2X7. P2X7-potentiation by a nanobody-based biologic was not effective alone to control tumor growth but enhanced tumor control and immune responses when used in combination with oxaliplatin chemotherapy. We also evaluated a bi-specific nanobody-based biologic that targets PD-L1 and CD73. This novel nanobody-based biologic exerted a potent anti-tumor effect, promoting tumor rejection and improving survival of mice in two tumor models. Hence, this study highlights the importance of purinergic checkpoints in tumor control and open new avenues for nanobody-based biologics that may be further exploited in the treatment of cancer.

The tumor microenvironment (TME) is a critical regulator of tumor growth, progression, and metastasis. Since immune cells represent a large fraction of the TME, they play a key role in mediating pro- and anti-tumor immune responses. Immune escape, which suppresses anti-tumor immunity, enables tumor cells to maintain their proliferation and growth. Numerous mechanisms, which have been intensively studied in recent years, are involved in this process and based on these findings, novel immunotherapies have been successfully developed. Here, we review the composition of the TME and the mechanisms by which immune evasive processes are regulated. In detail, we describe membrane-bound and soluble factors, their regulation, and their impact on immune cell activation in the TME. Furthermore, we give an overview of the tumor/antigen presentation and how it is influenced under malignant conditions. Finally, we summarize novel TME-targeting agents, which are already in clinical trials for different tumor entities.

Cancer remains the second most common cause of death worldwide affecting around 10 million patients every year. Among the therapeutic options, chemotherapeutic drugs are widely used but often associated with side effects. In addition, toxicity against immune cells may hamper anti-tumor immune responses. Some chemotherapeutic drugs, however, preserve immune functions and some can even stimulate anti-tumor immune responses through the induction of immunogenic cell death (ICD) rather than apoptosis. ICD stimulates the immune system by several mechanisms including the release of damage-associated molecular patterns (DAMPs) from dying cells. In this review, we will discuss the consequences of inducing two recently characterized forms of ICD, i.e., pyroptosis and necroptosis, in the tumor microenvironment (TME) and the perspectives they may offer to increase the immunogenicity of the so-called cold tumors and to stimulate effective anti-tumor immune responses.

Background and purpose: Activation of liver X receptor (LXR) by its ligand T0901317 (T317) enhances interferon-γ (IFNγ) production to inhibit tumor growth. However, induction of severe hypertriglyceridemia and fatty liver by T317 limits its application. The naphthylacetic acid modified D-enantiomeric-glycine-phenylalanine-phenylalanine-tyrosine (D-Nap-GFFY) can form a nanofiber hydrogel which is selectively taken up by antigen-presenting cells (APCs). In this study, we determined if D-Nap-GFFY-encapsulated T317 (D-Nap-GFFY-T317) can potently inhibit tumor growth while having no adverse lipogenic effects on the liver. Methods: We prepared D-Nap-GFFY-T317 nanofiber hydrogel and subcutaneously injected it into IFNγ deficient (IFNγ-/-) and wild-type (WT) mice with lung carcinoma, either inoculated LLC1 cells or urethane-induced carcinoma. Mice received oral T317 administration were used for comparison. Effects of treatment on tumor growth, lipogenesis and involved mechanisms were investigated. Results: Compared with T317 oral administration, injection of D-Nap-GFFY-T317 more potently inhibited LLC1 tumor growth in mice. The inhibition was dependent on LXR-activated IFNγ expression in APCs. D-Nap-GFFY-T317 increased M1 while reducing M2 type macrophages in tumors. Associated with activation of IFNγ expression, D-Nap-GFFY-T317 enhanced dendritic cell maturation and infiltration into tumors, increased CD3+/CD8+ cells in tumors, and inhibited tumor angiogenesis. Similarly, D-Nap-GFFY-T317 more potently inhibited growth of urethane-induced lung carcinomas than T317 oral administration. In these two tumor models, T317 oral administration, but not D-Nap-GFFY-T317 injection, activated hepatic lipogenesis and induced fatty liver. Conclusion: Our study demonstrates that D-Nap-GFFY-T317 inhibits lung tumor growth without adverse effects on the liver, indicating the hydrogel-encapsulated LXR ligand might be a novel therapy for tumor treatment.

Single-component adjuvant is prone to eliciting a specific type of Th1 or Th2 response. So, the development of combinatorial adjuvants inducing a robust mixed Th1/Th2 response is a promising vaccination strategy against cancer. Here, we describe a novel combination of aluminum salts (alum), CpG oligodeoxynucleotide (CpG) and innate defense regulator peptide HH2 for improving anti-tumor immune responses. The CpG-HH2 complex significantly enhanced the production of IFN-γ, TNF-α and IL-1β, promoted the uptake of antigen and strengthened the activation of p38, Erk1/2 and NF-κB in vitro, compared to CpG or HH2 alone. Immunization with NY-ESO-1 antigen plus alum-CpG-HH2 combinatorial adjuvant effectively inhibited tumor growth and reduced tumor burden in prophylactic and therapeutic tumor models and even in passive serum or cellular therapy. In addition, co-administration of NY-ESO-1 with alum-CpG-HH2 combinatorial adjuvant markedly activated NK cell cytotoxicity, induced antibody-dependent cellular cytotoxicity (ADCC), dramatically elicited cytotoxic T lymphocytes (CTLs) response, and increased infiltrating lymphocytes in tumors. Moreover, in vivo depletion of CD8+ T cells completely and depletion of NK cells partially blocked the anti-tumor activity of NY-ESO-1-alum-CpG-HH2 immunization. Overall, our results demonstrate a novel adjuvant combination for cancer vaccine with efficient immunomodulation by stimulating innate immunity and mediating adaptive immunity.