Topical Imiquimod Plus Nab-paclitaxel for Breast Cancer Cutaneous Metastases: A Phase 2 Clinical Trial

Targeting breast tumor extracellular matrix and stroma utilizing nanoparticles

Breast cancer is a complicated malignancy and is known as the most common cancer in women. Considerable experiments have been devoted to explore the basic impacts of the tumor stroma, particularly the extracellular matrix (ECM) and stromal components, on tumor growth and resistance to treatment. ECM is made up of an intricate system of proteins, glycosaminoglycans, and proteoglycans, and maintains structural support and controls key signaling pathways involved in breast tumors. ECM can block different drugs such as chemotherapy and immunotherapy drugs from entering the tumor stroma. Furthermore, the stromal elements, such as cancer-associated fibroblasts (CAFs), immune cells, and blood vessels, have crucial impacts on tumor development and therapeutic resistance. Recently, promising outcomes have been achieved in using nanotechnology for delivering drugs to tumor stroma and crossing ECM in breast malignancies. Nanoparticles have various benefits for targeting the breast tumor stroma, such as improved permeability and retention, extended circulation time, and the ability to actively target the area. This review covers the latest developments in nanoparticle therapies that focus on breast tumor ECM and stroma. We will explore different approaches using nanoparticles to target the delivery of anticancer drugs like chemotherapy, small molecule drugs, various antitumor products, and other specific synthetic therapeutic agents to the breast tumor stroma. Furthermore, we will investigate the utilization of nanoparticles in altering the stromal elements, such as reprogramming CAFs and immune cells, and also remodeling ECM.

Pirarubicin combined with TLR3 or TLR4 agonists enhances anti-tumor efficiency

BACKGROUND

Triple-negative breast cancer (TNBC) is prone to relapse due to the lack of effective therapeutic targets. Macrophages are the most abundant immune cells in the tumor microenvironment (TME) of breast cancer. Targeting the cross-talk between macrophages and cancer cells provides a more efficient strategy for anti-tumor therapy. Toll-like receptors (TLRs) are important players involved in macrophage activation, and TLR agonists are known to play roles in cancer therapy. However, the combination strategy of TLR agonists with chemotherapy drugs is still not well characterized.

METHODS

RT-PCR and Western blot were used to detect the expression of TLRs. The communication between breast cancer cells and macrophages were determined by co-culture in vitro. Tumor cells proliferation and migration were investigated by MTT assay and scratch wound assay. The effects of drug combinations and toxic side effects were assessed by immunohistochemistry and Hematoxylin & Eosin staining.

RESULTS

Expression of TLR3 and TLR4 were lower in breast tumor tissues compared with adjacent normal tissues. Patients with higher TLR3 or TLR4 expression levels had a better prognosis than those with lower expression levels. TLR3/4 expression was significantly inhibited when breast cancer cells MDA-MB-231 and E0771 were conditioned-cultured with macrophages in vitro and was also inhibited by pirarubicin (THP). However, the combination of TLR agonists and THP could reverse this response and inhibit the proliferation and migration of breast cancer cells. Additionally, this combination significantly reduced the tumor volume and weight in the murine model, increased the expression of TLR3/4 in mouse breast tumors.

CONCLUSIONS

Our results provide new ideas for the combination strategy of THP with TLR agonists which improves prognosis of breast cancer.

Personalized nanovaccines for treating solid cancer metastases

Cancer vaccines have garnered attention as a potential treatment for cancer metastases. Nevertheless, the clinical response rate to vaccines remains < 30%. Nanoparticles stabilize vaccines and improve antigen recognition and presentation, resulting in high tumor penetration or accumulation, effective co-distribution of drugs to the secondary lymphatic system, and adaptable antigen or adjuvant administration. Such vaccine-like nanomedicines have the ability to eradicate the primary tumors as well as to prevent or eliminate metastases. This review examines state-of-the-art nanocarriers developed to deliver tumor vaccines to metastases, including synthetic, semi-biogenic, and biogenic nanosystems. Moreover, it highlights the physical and pharmacological properties that enhance their anti-metastasis efficiency. This review also addresses the combination of nanovaccines with cancer immunotherapy to target various steps in the metastatic cascade, drawing insights from preclinical and clinical studies. The review concludes with a critical analysis of the challenges and frameworks linked to the clinical translation of cancer nanovaccines.

Targeting tumor-associated macrophages with mannosylated nanotherapeutics delivering TLR7/8 agonist enhances cancer immunotherapy

Tumor-associated macrophages (TAMs) constitute 50-80% of stromal cells in most solid tumors with high mortality and poor prognosis. Tumor-infiltrating dendritic cells (TIDCs) and TAMs are key components mediating immune responses within the tumor microenvironment (TME). Considering their refractory properties, simultaneous remodeling of TAMs and TIDCs is a potential strategy of boosting tumor immunity and restoring immunosurveillance. In this study, mannose-decorated poly(lactic-co-glycolic acid) nanoparticles loading with R848 (Man-pD-PLGA-NP@R848) were prepared to dually target TAMs and TIDCs for efficient tumor immunotherapy. The three-dimensional (3D) cell culture model can simulate tumor growth as influenced by the TME and its 3D structural arrangement. Consequently, cancer spheroids enriched with tumor-associated macrophages (TAMs) were fabricated to assess the therapeutic effectiveness of Man-pD-PLGA-NP@R848. In the TME, Man-pD-PLGA-NP@R848 targeted both TAMs and TIDCs in a mannose receptor-mediated manner. Subsequently, Man-pD-PLGA-NP@R848 released R848 to activate Toll-like receptors 7 and 8, following dual-reprograming of TIDCs and TAMs. Man-pD-PLGA-NP@R848 could uniquely reprogram TAMs into antitumoral phenotypes, decrease angiogenesis, reprogram the immunosuppressive TME from "cold tumor" into "hot tumor", with high CD4+ and CD8+ T cell infiltration, and consequently hinder tumor development in B16F10 tumor-bearing mice. Therefore, dual-reprograming of TIDCs and TAMs with the Man-pD-PLGA-NP@R848 is a promising cancer immunotherapy strategy.

Modulation of the tumor microenvironment and mechanism of immunotherapy-based drug resistance in breast cancer

Breast cancer, the most frequent female malignancy, is often curable when detected at an early stage. The treatment of metastatic breast cancer is more challenging and may be unresponsive to conventional therapy. Immunotherapy is crucial for treating metastatic breast cancer, but its resistance is a major limitation. The tumor microenvironment (TME) is vital in modulating the immunotherapy response. Various tumor microenvironmental components, such as cancer-associated fibroblasts (CAFs), tumor-associated macrophages (TAMs), and myeloid-derived suppressor cells (MDSCs), are involved in TME modulation to cause immunotherapy resistance. This review highlights the role of stromal cells in modulating the breast tumor microenvironment, including the involvement of CAF-TAM interaction, alteration of tumor metabolism leading to immunotherapy failure, and other latest strategies, including high throughput genomic screening, single-cell and spatial omics techniques for identifying tumor immune genes regulating immunotherapy response. This review emphasizes the therapeutic approach to overcome breast cancer immune resistance through CAF reprogramming, modulation of TAM polarization, tumor metabolism, and genomic alterations.

Huang Lian Jie Du Decoction enhances the anti-tumor efficacy of immune checkpoint inhibitors by activating TLR7/8 signalling in melanoma

BACKGROUND

The clinical application of immune checkpoint inhibitors (ICIs) is limited by their drug resistance, necessitating the development of ICI sensitizers to improve cancer immunotherapy outcomes. Huang Lian Jie Du Decoction (HLJD, Oren-gedoku-to in Japanese, Hwangryunhaedok-tang in Korean), a famous traditional Chinese medicinal prescription, has exhibited potential in the field of cancer treatment. This study aims to investigate the impact of HLJD on the efficacy of ICIs in melanoma and elucidate the underlying mechanisms.

METHODS

The potential synergistic effects of HLJD and ICIs were investigated on the tumor-bearing mice model of B16F10 melanoma, and the tumor infiltration of immune cells was tested by flow cytometry. The differential gene expression in tumors between HLJD and ICIs group and ICIs alone group were analyzed by RNA-seq. The effects of HLJD on oxidative stress, TLR7/8, and type I interferons (IFN-Is) signaling were further validated by immunofluorescence, PCR array, and immunochemistry in tumor tissue.

RESULTS

HLJD enhanced the anti-tumor effect of ICIs, significantly inhibited tumor growth, and prolonged the survival duration in melanoma. HLJD increased the tumor infiltration of anti-tumor immune cells, especially DCs, CD4+ T cells and CD8+T cells. Mechanically, HLJD activated the oxidative stress and TLR7/8 signaling pathway and IFN-Is-related genes in tumors.

CONCLUSIONS

HLJD enhanced the therapeutic benefits of ICIs in melanoma, through increasing reactive oxygen species (ROS), promoting the TLR7/8 pathway, and activating IFN-Is signaling, which in turn activated DCs and T cells.

Radiotherapy Combined with Intralesional Immunostimulatory Agents for Soft Tissue Sarcomas

Immunotherapy has shifted the treatment paradigm for many types of cancer. Unfortunately, the most commonly used immunotherapies, such as immune checkpoint inhibitors (ICI), have yielded limited benefit for most types of soft tissue sarcoma (STS). Radiotherapy (RT) is a mainstay of sarcoma therapy and can induce immune modulatory effects. Combining immunotherapy and RT in STS may be a promising strategy to improve sarcoma response to RT and increase the efficacy of immunotherapy. Most combination strategies have employed immunotherapies, such as ICI, that derepress immune suppressive networks. These have yielded only modest results, possibly due to the limited immune stimulatory effects of RT. Combining RT with immune stimulatory agents has yielded promising preclinical and clinical results but can be limited by the toxic nature of systemic administration of immune stimulants. Using intralesional immune stimulants may generate stronger RT immune modulation and less systemic toxicity, which may be a feasible strategy in accessible tumors such as STS. In this review, we summarize the immune modulatory effects of RT, the mechanism of action of various immune stimulants, including toll-like receptor agonists, and data for combinatorial strategies utilizing these agents.

Harnessing innate immune pathways for therapeutic advancement in cancer

The innate immune pathway is receiving increasing attention in cancer therapy. This pathway is ubiquitous across various cell types, not only in innate immune cells but also in adaptive immune cells, tumor cells, and stromal cells. Agonists targeting the innate immune pathway have shown profound changes in the tumor microenvironment (TME) and improved tumor prognosis in preclinical studies. However, to date, the clinical success of drugs targeting the innate immune pathway remains limited. Interestingly, recent studies have shown that activation of the innate immune pathway can paradoxically promote tumor progression. The uncertainty surrounding the therapeutic effectiveness of targeted drugs for the innate immune pathway is a critical issue that needs immediate investigation. In this review, we observe that the role of the innate immune pathway demonstrates heterogeneity, linked to the tumor development stage, pathway status, and specific cell types. We propose that within the TME, the innate immune pathway exhibits multidimensional diversity. This diversity is fundamentally rooted in cellular heterogeneity and is manifested as a variety of signaling networks. The pro-tumor effect of innate immune pathway activation essentially reflects the suppression of classical pathways and the activation of potential pro-tumor alternative pathways. Refining our understanding of the tumor's innate immune pathway network and employing appropriate targeting strategies can enhance our ability to harness the anti-tumor potential of the innate immune pathway and ultimately bridge the gap from preclinical to clinical application.

Nanoparticles for the Treatment of Bone Metastasis in Breast Cancer: Recent Advances and Challenges

Although the frequency of bone metastases from breast cancer has increased, effective treatment is lacking, prompting the development of nanomedicine, which involves the use of nanotechnology for disease diagnosis and treatment. Nanocarrier drug delivery systems offer several advantages over traditional drug delivery methods, such as higher reliability and biological activity, improved penetration and retention, and precise targeting and delivery. Various nanoparticles that can selectively target tumor cells without causing harm to healthy cells or organs have been synthesized. Recent advances in nanotechnology have enabled the diagnosis and prevention of metastatic diseases as well as the ability to deliver complex molecular "cargo" particles to metastatic regions. Nanoparticles can modulate systemic biodistribution and enable the targeted accumulation of therapeutic agents. Several delivery strategies are used to treat bone metastases, including untargeted delivery, bone-targeted delivery, and cancer cell-targeted delivery. Combining targeted agents with nanoparticles enhances the selective delivery of payloads to breast cancer bone metastatic lesions, providing multiple delivery advantages for treatment. In this review, we describe recent advances in nanoparticle development for treating breast cancer bone metastases.

Update on current and new potential immunotherapies in breast cancer, from bench to bedside

Impressive advances have been seen in cancer immunotherapy during the last years. Although breast cancer (BC) has been long considered as non-immunogenic, immunotherapy for the treatment of BC is now emerging as a new promising therapeutic approach with considerable potential. This is supported by a plethora of completed and ongoing preclinical and clinical studies in various types of immunotherapies. However, a significant gap between clinical oncology and basic cancer research impairs the understanding of cancer immunology and immunotherapy, hampering cancer therapy research and development. To exploit the accumulating available data in an optimal way, both fundamental mechanisms at play in BC immunotherapy and its clinical pitfalls must be integrated. Then, clinical trials must be critically designed with appropriate combinations of conventional and immunotherapeutic strategies. While there is room for major improvement, this updated review details the immunotherapeutic tools available to date, from bench to bedside, in the hope that this will lead to rethinking and optimizing standards of care for BC patients.

Harnessing the innate immune system by revolutionizing macrophage-mediated cancer immunotherapy

Immunotherapy is a promising and safer alternative to conventional cancer therapies. It involves adaptive T-cell therapy, cancer vaccines, monoclonal antibodies, immune checkpoint blockade (ICB), and chimeric antigen receptor (CAR) based therapies. However, most of these modalities encounter restrictions in solid tumours owing to a dense, highly hypoxic and immune-suppressive microenvironment as well as the heterogeneity of tumour antigens. The elevated intra-tumoural pressure and mutational rates within fastgrowing solid tumours present challenges in efficient drug targeting and delivery. The tumour microenvironment is a dynamic niche infiltrated by a variety of immune cells, most of which are macrophages. Since they form a part of the innate immune system, targeting macrophages has become a plausible immunotherapeutic approach. In this review, we discuss several versatile approaches (both at pre-clinical and clinical stages) such as the direct killing of tumour-associated macrophages, reprogramming pro-tumour macrophages to anti-tumour phenotypes, inhibition of macrophage recruitment into the tumour microenvironment, novel CAR macrophages, and genetically engineered macrophages that have been devised thus far. These strategies comprise a strong and adaptable macrophage-toolkit in the ongoing fight against cancer and by understanding their significance, we may unlock the full potential of these immune cells in cancer therapy.

Intratumoral Influenza Vaccine Administration Attenuates Breast Cancer Growth and Restructures the Tumor Microenvironment through Sialic Acid Binding of Vaccine Hemagglutinin

Breast cancer continues to have a high disease burden worldwide and presents an urgent need for novel therapeutic strategies to improve outcomes. The influenza vaccine offers a unique approach to enhance the anti-tumor immune response in patients with breast cancer. Our study explores the intratumoral use of the influenza vaccine in a triple-negative 4T1 mouse model of breast cancer. We show that the influenza vaccine attenuated tumor growth using a three-dose intratumoral regimen. More importantly, prior vaccination did not alter this improved anti-tumor response. Furthermore, we characterized the effect that the influenza vaccine has on the tumor microenvironment and the underlying mechanisms of action. We established that the vaccine facilitated favorable shifts in restructuring the tumor microenvironment. Additionally, we show that the vaccine's ability to bind sialic acid residues, which have been implicated in having oncogenic functions, emerged as a key mechanism of action. Influenza hemagglutinin demonstrated binding ability to breast cancer cells through sialic acid expression. When administered intratumorally, the influenza vaccine offers a promising therapeutic strategy for breast cancer patients by reshaping the tumor microenvironment and modestly suppressing tumor growth. Its interaction with sialic acids has implications for effective therapeutic application and future research.

Exploiting innate immunity for cancer immunotherapy

Immunotherapies have revolutionized the treatment paradigms of various types of cancers. However, most of these immunomodulatory strategies focus on harnessing adaptive immunity, mainly by inhibiting immunosuppressive signaling with immune checkpoint blockade, or enhancing immunostimulatory signaling with bispecific T cell engager and chimeric antigen receptor (CAR)-T cell. Although these agents have already achieved great success, only a tiny percentage of patients could benefit from immunotherapies. Actually, immunotherapy efficacy is determined by multiple components in the tumor microenvironment beyond adaptive immunity. Cells from the innate arm of the immune system, such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, natural killer cells, and unconventional T cells, also participate in cancer immune evasion and surveillance. Considering that the innate arm is the cornerstone of the antitumor immune response, utilizing innate immunity provides potential therapeutic options for cancer control. Up to now, strategies exploiting innate immunity, such as agonists of stimulator of interferon genes, CAR-macrophage or -natural killer cell therapies, metabolic regulators, and novel immune checkpoint blockade, have exhibited potent antitumor activities in preclinical and clinical studies. Here, we summarize the latest insights into the potential roles of innate cells in antitumor immunity and discuss the advances in innate arm-targeted therapeutic strategies.

Topical Calcipotriol Plus Imiquimod Immunotherapy for Nonkeratinocyte Skin Cancers

Nonkeratinocyte cutaneous malignancies, including breast cancer cutaneous metastasis and melanoma in situ, are often poor surgical candidates. Imiquimod (IMQ), a toll-like receptor 7 agonist that activates innate immunity in the skin, is used to treat these cutaneous malignancies. However, IMQ's modest effect on the activation of adaptive immunity limits its efficacy as a monotherapy. In this study, we demonstrate that topical TSLP cytokine inducers-calcipotriol and retinoic acid-synergize with IMQ to activate CD4+ T-cell immunity against nonkeratinocyte cutaneous malignancies. Topical calcipotriol plus IMQ treatment reduced breast tumor growth compared with calcipotriol or IMQ alone (P < 0.0001). Calcipotriol plus IMQ-mediated tumor suppression was associated with significant infiltration of CD4+ effector T cells in the tumor microenvironment. Notably, topical calcipotriol plus IMQ immunotherapy enabled immune checkpoint blockade therapy to effectively control immunologically cold breast tumors, which was associated with induction of CD4+ T-cell immunity. Topical treatment with calcipotriol plus IMQ and retinoic acid plus IMQ also blocked subcutaneous melanoma growth. These findings highlight the synergistic effect of topical TSLP induction in combination with innate immune cell activation as an effective immunotherapy for malignancies affecting the skin.

Recent Advancements and Strategies for Overcoming the Blood-Brain Barrier Using Albumin-Based Drug Delivery Systems to Treat Brain Cancer, with a Focus on Glioblastoma

Glioblastoma multiforme (GBM) is a highly aggressive malignant tumor, and the most prevalent primary malignant tumor affecting the brain and central nervous system. Recent research indicates that the genetic profile of GBM makes it resistant to drugs and radiation. However, the main obstacle in treating GBM is transporting drugs through the blood-brain barrier (BBB). Albumin is a versatile biomaterial for the synthesis of nanoparticles. The efficiency of albumin-based delivery systems is determined by their ability to improve tumor targeting and accumulation. In this review, we will discuss the prevalence of human glioblastoma and the currently adopted treatment, as well as the structure and some essential functions of the BBB, to transport drugs through this barrier. We will also mention some aspects related to the blood-tumor brain barrier (BTBB) that lead to poor treatment efficacy. The properties and structure of serum albumin were highlighted, such as its role in targeting brain tumors, as well as the progress made until now regarding the techniques for obtaining albumin nanoparticles and their functionalization, in order to overcome the BBB and treat cancer, especially human glioblastoma. The albumin drug delivery nanosystems mentioned in this paper have improved properties and can overcome the BBB to target brain tumors.

A Phase I/II Trial of HER2 Vaccine-Primed Autologous T-Cell Infusions in Patients with Treatment Refractory HER2-Overexpressing Breast Cancer

PURPOSE

High levels of type I T cells are needed for tumor eradication. We evaluated whether the HER2-specific vaccine-primed T cells are readily expanded ex vivo to achieve levels needed for therapeutic infusion.

PATIENTS AND METHODS

Phase I/II nonrandomized trial of escalating doses of ex vivo-expanded HER2-specific T cells after in vivo priming with a multiple peptide-based HER2 intracellular domain (ICD) vaccine. Vaccines were given weekly for a total of three immunizations. Two weeks after the third vaccine, patients underwent leukapheresis for T-cell expansion, then received three escalating cell doses over 7- to 10-day intervals. Booster vaccines were administered after the T-cell infusions. The primary objective was safety. The secondary objectives included extent and persistence of HER2-specific T cells, development of epitope spreading, and clinical response. Patients received a CT scan prior to enrollment and 1 month after the last T-cell infusion.

RESULTS

Nineteen patients received T-cell infusions. Treatment was well tolerated. One month after the last T-cell infusion, 82% of patients had significantly augmented T cells to at least one of the immunizing epitopes and 81% of patients demonstrated enhanced intramolecular epitope spreading compared with baseline (P < 0.05). There were no complete responses, one partial response (6%), and eight patients with stable disease (47%), for a disease control rate of 53%. The median survival for those with progressive disease was 20.5 months and for responders (PR+SD) was 45.0 months.

CONCLUSIONS

Adoptive transfer of HER2 vaccine-primed T cells was feasible, was associated with minimal toxicity, and resulted in an increased overall survival in responding patients. See related commentary by Crosby et al., p. 3256.

Anti-Tumor Strategies by Harnessing the Phagocytosis of Macrophages

Macrophages are essential for the human body in both physiological and pathological conditions, engulfing undesirable substances and participating in several processes, such as organism growth, immune regulation, and maintenance of homeostasis. Macrophages play an important role in anti-bacterial and anti-tumoral responses. Aberrance in the phagocytosis of macrophages may lead to the development of several diseases, including tumors. Tumor cells can evade the phagocytosis of macrophages, and "educate" macrophages to become pro-tumoral, resulting in the reduced phagocytosis of macrophages. Hence, harnessing the phagocytosis of macrophages is an important approach to bolster the efficacy of anti-tumor treatment. In this review, we elucidated the underlying phagocytosis mechanisms, such as the equilibrium among phagocytic signals, receptors and their respective signaling pathways, macrophage activation, as well as mitochondrial fission. We also reviewed the recent progress in the area of application strategies on the basis of the phagocytosis mechanism, including strategies targeting the phagocytic signals, antibody-dependent cellular phagocytosis (ADCP), and macrophage activators. We also covered recent studies of Chimeric Antigen Receptor Macrophage (CAR-M)-based anti-tumor therapy. Furthermore, we summarized the shortcomings and future applications of each strategy and look into their prospects with the hope of providing future research directions for developing the application of macrophage phagocytosis-promoting therapy.

Nanoparticles in the diagnosis and treatment of cancer metastases: Current and future perspectives

Metastasis accounts for greater than 90% of cancer-related deaths. Despite recent advancements in conventional chemotherapy, immunotherapy, targeted therapy, and their rational combinations, metastatic cancers remain essentially untreatable. The distinct obstacles to treat metastases include their small size, high multiplicity, redundancy, therapeutic resistance, and dissemination to multiple organs. Recent advancements in nanotechnology provide the numerous applications in the diagnosis and prophylaxis of metastatic diseases, including the small particle size to penetrate cell membrane and blood vessels and their capacity to transport complex molecular 'cargo' particles to various metastatic regions such as bones, brain, liver, lungs, and lymph nodes. Indeed, nanoparticles (NPs) have demonstrated a significant ability to target specific cells within these organs. In this regard, the purpose of this review is to summarize the present state of nanotechnology in terms of its application in the diagnosis and treatment of metastatic cancer. We intensively reviewed applications of NPs in fluorescent imaging, PET scanning, MRI, and photoacoustic imaging to detect metastasis in various cancer models. The use of targeted NPs for cancer ablation in conjunction with chemotherapy, photothermal treatment, immuno therapy, and combination therapy is thoroughly discussed. The current review also highlights the research opportunities and challenges of leveraging engineering technologies with cancer cell biology and pharmacology to fabricate nanoscience-based tools for treating metastases.

DKK1 Promotes Tumor Immune Evasion and Impedes Anti-PD-1 Treatment by Inducing Immunosuppressive Macrophages in Gastric Cancer

Tumor-associated macrophages (TAM) have key functions in promoting a suppressive tumor immune microenvironment (TIME) and immune evasion, which largely limit treatment effects of immune-checkpoint inhibitors (ICI) in different cancers, including gastric cancer. Dickkopf-1 (DKK1) is associated with tumor progression and has been shown to negatively regulate antitumor immunity, but the impact of DKK1 on the TIME remains incompletely understood. Here, we found that tumoral DKK1 expression is closely associated with worse survival and a suppressive TIME in gastric cancer patients. Results from in vitro coculture assays suggested that DKK1 induces macrophages to become immunosuppressive, thereby inhibiting antitumor responses of CD8+ T cells and natural killer (NK) cells. In vivo DKK1 blockade in syngeneic gastric cancer mouse models reprogramed TAMs to restore the immune activity in the TIME and triggered significant tumor regression. DKK1 blockade also directly reduced the growth of human gastric cancer tumors with high DKK1 expression in a xenograft model. Mechanistically, DKK1 interacted with cytoskeleton-associated protein 4 (CKAP4) on the macrophage surface and activated downstream PI3K-AKT signaling, which contributed to immune suppression. TAM reprogramming by DKK1 blockade also augmented the efficacy of programmed cell death protein-1 (PD-1) blockade in gastric cancer models. Therefore, our study provides novel insights into the role of DKK1 on tumor-intrinsic, innate, and adaptive antitumor immunity modulation and suggests that DKK1 is a promising immunotherapeutic target for enhanced PD-1 blockade therapy in gastric cancer.

Anticancer Nanotherapeutics in Clinical Trials: The Work behind Clinical Translation of Nanomedicine

The ultimate goal of nanomedicine has always been the generation of translational technologies that can ameliorate current therapies. Cancer disease represented the primary target of nanotechnology applied to medicine, since its clinical management is characterized by very toxic therapeutics. In this effort, nanomedicine showed the potential to improve the targeting of different drugs by improving their pharmacokinetics properties and to provide the means to generate new concept of treatments based on physical treatments and biologics. In this review, we considered different platforms that reached the clinical trial investigation, providing an objective analysis about their physical and chemical properties and the working mechanism at the basis of their tumoritr opic properties. With this review, we aim to help other scientists in the field in conceiving their delivering platforms for clinical translation by providing solid examples of technologies that eventually were tested and sometimes approved for human therapy.

Cellular Target Deconvolution of Small Molecules Using a Selection-Based Genetic Screening Platform

Small-molecule drug target identification is an essential and often rate-limiting step in phenotypic drug discovery and remains a major challenge. Here, we report a novel platform for target identification of activators of signaling pathways by leveraging the power of a clustered regularly interspaced short palindromic repeats (CRISPR) knockout library. This platform links the expression of a suicide gene to the small-molecule-activated signaling pathway to create a selection system. With this system, loss-of-function screening using a CRISPR single-guide (sg) RNA library positively enriches cells in which the target has been knocked out. The identities of the drug targets and other essential genes required for the activity of small molecules of interest are then uncovered by sequencing. We tested this platform on BDW568, a newly discovered type-I interferon signaling activator, and identified stimulator of interferon genes (STING) as its target and carboxylesterase 1 (CES1) to be a key metabolizing enzyme required to activate BDW568 for target engagement. The platform we present here can be a general method applicable for target identification for a wide range of small molecules that activate different signaling pathways.

Intratumoral delivery of TransCon™ TLR7/8 Agonist promotes sustained anti-tumor activity and local immune cell activation while minimizing systemic cytokine induction

Background

Intratumoral (IT) delivery of toll-like receptor (TLR) agonists has shown encouraging anti-tumor benefit in preclinical and early clinical studies. However, IT delivery of TLR agonists may lead to rapid effusion from the tumor microenvironment (TME), potentially limiting the duration of local inflammation and increasing the risk of systemic adverse events.

Methods

To address these limitations, TransCon^™ TLR7/8 Agonist—an investigational sustained-release prodrug of resiquimod that uses a TransCon linker and hydrogel technology to achieve sustained and predictable IT release of resiquimod—was developed. TransCon TLR7/8 Agonist was characterized for resiquimod release in vitro and in vivo, in mice and rats, and was assessed for anti-tumor efficacy and pharmacodynamic activity in mice.

Results

Following a single IT dose, TransCon TLR7/8 Agonist mediated potent tumor growth inhibition which was associated with sustained resiquimod release over several weeks with minimal induction of systemic cytokines. TransCon TLR7/8 Agonist monotherapy promoted activation of antigen-presenting cells in the TME and tumor-draining lymph nodes, with evidence of activation and expansion of CD8⁺ T cells in the tumor-draining lymph node and TME. Combination of TransCon TLR7/8 Agonist with systemic immunotherapy further promoted anti-tumor activity in TransCon TLR7/8 Agonist-treated tumors. In a bilateral tumor setting, combination of TransCon TLR7/8 Agonist with systemic IL-2 potentiated tumor growth inhibition in both injected and non-injected tumors and conferred protection against tumor rechallenge following complete regressions.

Conclusions

Our findings show that a single dose of TransCon TLR7/8 Agonist can mediate sustained local release of resiquimod in the TME and promote potent anti-tumor effects as monotherapy and in combination with systemic immunotherapy, supporting TransCon TLR7/8 Agonist as a novel intratumoral TLR agonist for cancer therapy. A clinical trial to evaluate the safety and efficacy of TransCon TLR7/8 Agonist, as monotherapy and in combination with pembrolizumab, in cancer patients is currently ongoing (transcendIT-101; NCT04799054).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02708-6.

Circulating inflammatory cells in patients with metastatic breast cancer: Implications for treatment

Adaptive and innate immune cells play a crucial role as regulators of cancer development.

Inflammatory cells in blood flow seem to be involved in pro-tumor activities and contribute to breast cancer progression. Circulating lymphocyte ratios such as the platelet-lymphocytes ratio (PLR), the monocyte-lymphocyte ratio (MLR) and the neutrophil-lymphocyte ratio (NLR) are new reproducible, routinely feasible and cheap biomarkers of immune response. These indexes have been correlated to prognosis in many solid tumors and there is growing evidence on their clinical applicability as independent prognostic markers also for breast cancer.

In this review we give an overview of the possible value of lymphocytic indexes in advanced breast cancer prognosis and prediction of outcome. Furthermore, targeting the immune system appear to be a promising therapeutic strategy for breast cancer, especially macrophage-targeted therapies. Herein we present an overview of the ongoing clinical trials testing systemic inflammatory cells as therapeutic targets in breast cancer.

Host-pathogen protein-nucleic acid interactions: A comprehensive review

Recognition of pathogen-derived nucleic acids by host cells is an effective host strategy to detect pathogenic invasion and trigger immune responses. In the context of pathogen-specific pharmacology, there is a growing interest in mapping the interactions between pathogen-derived nucleic acids and host proteins. Insight into the principles of the structural and immunological mechanisms underlying such interactions and their roles in host defense is necessary to guide therapeutic intervention. Here, we discuss the newest advances in studies of molecular interactions involving pathogen nucleic acids and host factors, including their drug design, molecular structure and specific patterns. We observed that two groups of nucleic acid recognizing molecules, Toll-like receptors (TLRs) and the cytoplasmic retinoic acid-inducible gene (RIG)-I-like receptors (RLRs) form the backbone of host responses to pathogen nucleic acids, with additional support provided by absent in melanoma 2 (AIM2) and DNA-dependent activator of Interferons (IFNs)-regulatory factors (DAI) like cytosolic activity. We review the structural, immunological, and other biological aspects of these representative groups of molecules, especially in terms of their target specificity and affinity and challenges in leveraging host-pathogen protein-nucleic acid interactions (HP-PNI) in drug discovery.

Cutaneous metastasectomy: Is there a role in breast cancer? A systematic review and overview of current treatment modalities

Cutaneous metastases (CM) are neoplastic lesions involving the dermis or subcutaneous tissues, originating from another primary tumor. Breast cancer is commonest primary solid tumor, representing 24%-50% of CM patients. There is no "standard of care" on management. In particular, the role of surgery in the treatment of cutaneous metastases from breast carcinoma (CMBC) remains controversial. This systematic review evaluates the role of cutaneous metastasectomy in breast cancer and provides an overview of existing treatment types.

Cutaneous Breast Cancer Metastasis Is Effectively Treated With Intralesional Interleukin-2 and Imiquimod: A Case Report and Brief Literature Review

Breast cancer is the most common non-cutaneous cancer affecting women worldwide and is a major cause of cancer-related morbidity and mortality in females. While many women are diagnosed with early-stage disease, a subset of women may present with isolated cutaneous metastases or recurrent locoregional cutaneous metastatic disease. There is a paucity of evidence for effective treatments for cutaneous breast cancer metastases. Herein, we present a case of hormone receptor negative, HER2 positive cutaneous breast cancer metastasis treated with intralesional IL-2 and topical imiquimod, which was well tolerated with only minor low grade side effects. We also present a brief literature review of immunotherapy for cutaneous breast cancer metastasis to frame the discussion around using minimally invasive local therapies for this disease. Together, this limited data suggests that intralesional IL-2 and imiquimod may be considered as a safe option when treating a patient with cutaneous breast cancer metastases.

The Role of Toll-like Receptor Agonists and Their Nanomedicines for Tumor Immunotherapy

Toll-like receptors (TLRs) are a class of pattern recognition receptors that play a critical role in innate and adaptive immunity. Toll-like receptor agonists (TLRa) as vaccine adjuvant candidates have become one of the recent research hotspots in the cancer immunomodulatory field. Nevertheless, numerous current systemic deliveries of TLRa are inappropriate for clinical adoption due to their low efficiency and systemic adverse reactions. TLRa-loaded nanoparticles are capable of ameliorating the risk of immune-related toxicity and of strengthening tumor suppression and eradication. Herein, we first briefly depict the patterns of TLRa, followed by the mechanism of agonists at those targets. Second, we summarize the emerging applications of TLRa-loaded nanomedicines as state-of-the-art strategies to advance cancer immunotherapy. Additionally, we outline perspectives related to the development of nanomedicine-based TLRa combined with other therapeutic modalities for malignancies immunotherapy.

Nano-Based Approved Pharmaceuticals for Cancer Treatment: Present and Future Challenges

Cancer is one of the main causes of death worldwide. To date, and despite the advances in conventional treatment options, therapy in cancer is still far from optimal due to the non-specific systemic biodistribution of antitumor agents. The inadequate drug concentrations at the tumor site led to an increased incidence of multiple drug resistance and the appearance of many severe undesirable side effects. Nanotechnology, through the development of nanoscale-based pharmaceuticals, has emerged to provide new and innovative drugs to overcome these limitations. In this review, we provide an overview of the approved nanomedicine for cancer treatment and the rationale behind their designs and applications. We also highlight the new approaches that are currently under investigation and the perspectives and challenges for nanopharmaceuticals, focusing on the tumor microenvironment and tumor disseminate cells as the most attractive and effective strategies for cancer treatments.

Potential molecular mechanisms and clinical progress in liver metastasis of breast cancer

Breast cancer is the most common malignant tumor in women and the leading cause of cancer death in women. About 30% of breast cancer patients have metastasis every year, which greatly increases the mortality rate of breast cancer. The main target organs for metastasis are bone, brain, liver and lung. The breast cancer liver metastasis (BCLM) mechanism is not fully clarified. This is a complex process involving multiple factors, which is not only related to the microenvironment of the primary tumor and liver, but also regulated by a variety of signaling pathways. Clarifying these mechanisms is of great help to guide clinical treatment. With the in-depth study of BCLM, a variety of new treatment schemes such as targeted therapy and endocrine therapy provide new ideas for the cure of BCLM. In this review, we will summarize the molecular mechanism and treatment of BCLM.

Bibliometric analysis of toll-like receptor agonists associated with cancer therapy

BACKGROUND

Toll-like receptors (TLRs), a family of innate pattern-recognition receptors, have been exploited as a target for antitumor strategy. An increasing number of TLR agonists, serving as immunotherapeutics or vaccine adjuvants, were developed. This study aimed at exploring the status and trend of current researches on TLR agonists through bibliometric analysis.

METHODS

Original publications on TLR agonists were collected from the Web of Science Core Collection. Data were analyzed in terms of publication outputs, journals, countries, institutions, authors, co-authorship, co-citation, research hotspots, and evolution trends through VOSviewer and CiteSpace.

RESULTS

A total of 1914 TLR agonists-related articles, published in 612 academic journals between 2000 and 2019, were enrolled in the study. The Journal of Immunology published the most publications, followed by PLoS One and Blood. The USA that is in possession of the largest number of articles and the most extensive cooperators was the most leading country in this field. University of Minnesota ranked the first in terms of paper totality, but its average citations ranking was lower than University of Pennsylvania. Gudkov AV was the most productive author, whose team reported a TLR5 agonist that had radioprotective activity in mouse and primate models in 2008. The paper of Akira Shizuo, professor of Osaka University, was widely cited by international peers. The research trend of TLR agonists has undergone 3 periods: mechanisms of TLR signalings in immunotherapy (2000-2010), discovery of TLR agonists (2011-2014), application, therapeutic evaluation, and drug design of TLR agonists (2015-2019).

CONCLUSION

This study provides investigators a landscape of TLR agonists research from the perspective of bibliometrics.

Screening and predicted value of potential biomarkers for breast cancer using bioinformatics analysis

Breast cancer is the most common cancer and the leading cause of cancer-related deaths in women. Increasing molecular targets have been discovered for breast cancer prognosis and therapy. However, there is still an urgent need to identify new biomarkers. Therefore, we evaluated biomarkers that may aid the diagnosis and treatment of breast cancer. We searched three mRNA microarray datasets (GSE134359, GSE31448 and GSE42568) and identified differentially expressed genes (DEGs) by comparing tumor and non-tumor tissues using GEO2R. Functional and pathway enrichment analyses of the DEGs were performed using the DAVID database. The protein-protein interaction (PPI) network was plotted with STRING and visualized using Cytoscape. Module analysis of the PPI network was done using MCODE. The associations between the identified genes and overall survival (OS) were analyzed using an online Kaplan-Meier tool. The redundancy analysis was conducted by DepMap. Finally, we verified the screened HUB gene at the protein level. A total of 268 DEGs were identified, which were mostly enriched in cell division, cell proliferation, and signal transduction. The PPI network comprised 236 nodes and 2132 edges. Two significant modules were identified in the PPI network. Elevated expression of the genes Discs large-associated protein 5 (DLGAP5), aurora kinase A (AURKA), ubiquitin-conjugating enzyme E2 C (UBE2C), ribonucleotide reductase regulatory subunit M2(RRM2), kinesin family member 23(KIF23), kinesin family member 11(KIF11), non-structural maintenance of chromosome condensin 1 complex subunit G (NCAPG), ZW10 interactor (ZWINT), and denticleless E3 ubiquitin protein ligase homolog(DTL) are associated with poor OS of breast cancer patients. The enriched functions and pathways included cell cycle, oocyte meiosis and the p53 signaling pathway. The DEGs in breast cancer have the potential to become useful targets for the diagnosis and treatment of breast cancer.

Clinically Translatable Approaches of Inhibiting TGF-β to Target Cancer Stem Cells in TNBC

Triple-negative breast cancer (TNBC) is a subtype of breast cancer that disproportionally accounts for the majority of breast cancer-related deaths due to the lack of specific targets for effective treatments. In this review, we highlight the complexity of the transforming growth factor-beta family (TGF-β) pathway and discuss how the dysregulation of the TGF-β pathway promotes oncogenic attributes in TNBC, which negatively affects patient prognosis. Moreover, we discuss recent findings highlighting TGF-β inhibition as a potent method to target mesenchymal (CD44⁺/CD24^-) and epithelial (ALDH^high) cancer stem cell (CSC) populations. CSCs are associated with tumorigenesis, metastasis, relapse, resistance, and diminished patient prognosis; however, due to differential signal pathway enrichment and plasticity, these populations remain difficult to target and persist as a major barrier barring successful therapy. This review highlights the importance of TGF-β as a driver of chemoresistance, radioresistance and reduced patient prognosis in breast cancer and highlights novel treatment strategies which modulate TGF-β, impede cancer progression and reduce the rate of resistance generation via targeting the CSC populations in TNBC and thus reducing tumorigenicity. Potential TGF-β inhibitors targeting based on clinical trials are summarized for further investigation, which may lead to the development of novel therapies to improve TNBC patient prognosis.

Toll-Like Receptors in Stem/Progenitor Cells

One of the bridges that control the cross-talk between the innate and adaptive immune systems is toll-like receptors (TLRs). TLRs interact with molecules shared and maintained by the source pathogens, but also with endogenous molecules derived from injured tissues (damage/danger-associated molecular patterns - DAMPs). This is likely why some kinds of stem/progenitor cells (SCs) have been found to express TLRs. The role of TLRs in regulating basal motility, proliferation, processes of differentiation, self-renewal, and immunomodulation has been demonstrated in these cells. In this book chapter, we will discuss the many different functions assumed by the TLRs in SCs, pointing out that, depending on the context and the type of ligands they perceive, they may have different effects. In addition, the role of TLR in SC's response to specific tissue damage and in reparative processes will be addressed, as well as how the discovery of molecules mediating TLR signaling's differential function may be decisive for the development of new therapeutic strategies. Given the available studies on TLRs in SCs, the significance of TLRs in sensing an injury to stem/progenitor cells and evaluating their action and reparative activity, which depends on the circumstances, will be discussed here. It could also be possible that SCs used in therapy could theoretically be exposed to TLR ligands, which could modulate their in vivo therapeutic potential. In this context, we need to better understand the mechanisms of action of TLRs on SCs and learn how to regulate these receptors and their downstream pathways in a precise way in order to modulate SC proliferation, survival, migration, and differentiation in the pathological environment. In this way, cell therapy may be strengthened and made safer in the future.

Immunization with a Plasmid DNA Vaccine Encoding the N-Terminus of Insulin-like Growth Factor Binding Protein-2 in Advanced Ovarian Cancer Leads to High-level Type I Immune Responses

BACKGROUND

Cancer vaccines targeting nonmutated proteins elicit limited type I T-cell responses and can generate regulatory and type II T cells. Class II epitopes that selectively elicit type I or type II cytokines can be identified in nonmutated cancer-associated proteins. In mice, a T-helper I (Th1) selective insulin-like growth factor binding protein-2 (IGFBP-2) N-terminus vaccine generated high levels of IFNγ secreting T cells, no regulatory T cells, and significant antitumor activity. We conducted a phase I trial of T-helper 1 selective IGFBP-2 vaccination in patients with advanced ovarian cancer.

METHODS

Twenty-five patients were enrolled. The IGFBP-2 N-terminus plasmid-based vaccine was administered monthly for 3 months. Toxicity was graded by NCI criteria and antigen-specific T cells measured by IFNγ/IL10 ELISPOT. T-cell diversity and phenotype were assessed.

RESULTS

The vaccine was well tolerated, with 99% of adverse events graded 1 or 2, and generated high levels of IGFBP-2 IFNγ secreting T cells in 50% of patients. Both Tbet⁺ CD4 (P = 0.04) and CD8 (P = 0.007) T cells were significantly increased in immunized patients. There was no increase in GATA3⁺ CD4 or CD8, IGFBP-2 IL10 secreting T cells, or regulatory T cells. A significant increase in T-cell clonality occurred in immunized patients (P = 0.03, pre- vs. post-vaccine) and studies showed the majority of patients developed epitope spreading within IGFBP-2 and/or to other antigens. Vaccine nonresponders were more likely to have preexistent IGFBP-2 specific immunity and demonstrated defects in CD4 T cells, upregulation of PD-1, and downregulation of genes associated with T-cell activation, after immunization.

CONCLUSIONS

IGFBP-2 N-terminus Th1 selective vaccination safely induces type I T cells without evidence of regulatory responses.

Combination Treatment of Topical Imiquimod Plus Anti-PD-1 Antibody Exerts Significantly Potent Antitumor Effect

The exact mechanisms of the imiquimod (IMQ)-induced antitumor effect have not been fully understood. Although both topical IMQ treatment and anti-PD-1 antibody may be used for primary skin lesions or skin metastases of various cancers, the efficacy of each monotherapy for these lesions is insufficient. Using a murine tumor model and human samples, we aimed to elucidate the detailed mechanisms of the IMQ-induced antitumor effect and analyzed the antitumor effect of combination therapy of topical IMQ plus anti-PD-1 antibody. Topical IMQ significantly suppressed the tumor growth of MC38 in wildtype mice. IMQ upregulated interferon γ (IFN-γ) expression in CD8⁺ T cells in both the lymph nodes and the tumor, and the antitumor effect was abolished in both Rag1-deficient mice and IFN-γ-deficient mice, indicating that IFN-γ produced by CD8⁺ T cells play a crucial role in the IMQ-induced antitumor effect. IMQ also upregulated PD-1 expression in T cells as well as PD-L1/PD-L2 expression in myeloid cells, suggesting that IMQ induces not only T-cell activation but also T-cell exhaustion by enhanced PD-1 inhibitory signaling. Combination therapy of topical IMQ plus anti-PD-1 antibody exerted a significantly potent antitumor effect when compared with each single therapy, indicating that the combination therapy is a promising therapy for the skin lesions of various cancers.

A case report of imiquimod topical therapy as treatment for cutaneous metastasis of breast cancer

Cutaneous metastasis of breast cancer carries a poor prognosis, invokes a poor quality of life, and increases mortality by raising one’s risk of bleeding and infection. Currently, options for treatment are systemic chemotherapy, surgical resection and radiation. These treatments are invasive and can have toxic side effects. A 50-year-old African-American woman with stage IV breast cancer with cutaneous metastasis to the left anterior chest and left supraclavicular area was successfully treated with topical imiquimod. She experienced improvement in appearance and symptoms within several months of starting treatment, resulting in near resolution of her cutaneous metastasis. Imiquimod is currently approved for several cutaneous conditions and has the potential to treat cutaneous metastasis of breast cancer.

Toll-Like Receptor-Based Strategies for Cancer Immunotherapy

Toll-like receptors (TLRs) are expressed and play multiple functional roles in a variety of immune cell types involved in tumor immunity. There are plenty of data on the pharmacological targeting of TLR signaling using agonist molecules that boost the antitumor immune response. A recent body of research has also demonstrated promising strategies for improving the cell-based immunotherapy methods by inducing TLR signaling. These strategies include systemic administration of TLR antagonist along with immune cell transfer and also genetic engineering of the immune cells using TLR signaling components to improve the function of genetically engineered immune cells such as chimeric antigen receptor-modified T cells. Here, we explore the current status of the cancer immunotherapy approaches based on manipulation of TLR signaling to provide a perspective of the underlying rationales and potential clinical applications. Altogether, reviewed publications suggest that TLRs make a potential target for the immunotherapy of cancer.

Myeloid-derived suppressor cells in cancer immunotherapy-clinical perspectives

Myeloid-derived suppressor cells (MDSCs) are heterogeneous and poorly mature cells of innate immunity that their population is increased substantially in cancer patients. MDSCs represent three subsets including CD14⁺ monocytic (M), CD15⁺ granulocytic (G) and Lin^- early precursor (e) cells. MDSCs release a number of factors that direct several tumorigenic-related events including immune evasion, angiogenesis and metastasis. Assessment of MDSCs can provide valuable information from cancer immunity state, and it can be an indicator of tumor prognosis. The cells can be targeted in combination with current immunotherapeutic schedules, and the outcomes were promising. The focus of this review is to provide an overview of MDSCs, their involvement in tumor-related immunosuppression, and their impact on cancer immunotherapy. Then, strategies are proposed to boost the power of immune system against MDSCs.

Nanomaterial-based delivery vehicles for therapeutic cancer vaccine development

Nanomaterial-based delivery vehicles such as lipid-based, polymer-based, inorganics-based, and bio-inspired vehicles often carry distinct and attractive advantages in the development of therapeutic cancer vaccines. Based on various delivery vehicles, specifically designed nanomaterials-based vaccines are highly advantageous in boosting therapeutic and prophylactic antitumor immunities. Specifically, therapeutic vaccines featuring unique properties have made major contributions to the enhancement of antigen immunogenicity, encapsulation efficiency, biocompatibility, and stability, as well as promoting antigen cross-presentation and specific CD8+ T cell responses. However, for clinical applications, tumor-associated antigen-derived vaccines could be an obstacle, involving immune tolerance and deficiency of tumor specificities, in achieving maximum therapeutic indices. However, when using bioinformatics predictions with emerging innovations of in silico tools, neoantigen-based therapeutic vaccines might become potent personalized vaccines for tumor treatments. In this review, we summarize the development of preclinical therapeutic cancer vaccines and the advancements of nanomaterial-based delivery vehicles for cancer immunotherapies, which provide the basis for a personalized vaccine delivery platform. Moreover, we review the existing challenges and future perspectives of nanomaterial-based personalized vaccines for novel tumor immunotherapies.

Mechanisms of Macrophage Plasticity in the Tumor Environment: Manipulating Activation State to Improve Outcomes

Macrophages are a specialized class of innate immune cells with multifaceted roles in modulation of the inflammatory response, homeostasis, and wound healing. While developmentally derived or originating from circulating monocytes, naïve macrophages can adopt a spectrum of context-dependent activation states ranging from pro-inflammatory (classically activated, M1) to pro-wound healing (alternatively activated, M2). Tumors are known to exploit macrophage polarization states to foster a tumor-permissive milieu, particularly by skewing macrophages toward a pro-tumor (M2) phenotype. These pro-tumoral macrophages can support cancer progression by several mechanisms including immune suppression, growth factor production, promotion of angiogenesis and tissue remodeling. By preventing the adoption of this pro-tumor phenotype or reprogramming these macrophages to a more pro-inflammatory state, it may be possible to inhibit tumor growth. Here, we describe types of tumor-derived signaling that facilitate macrophage reprogramming, including paracrine signaling and activation of innate immune checkpoints. We also describe intervention strategies targeting macrophage plasticity to limit disease progression and address their implications in cancer chemo- and immunotherapy.

Macrophage reprogramming for therapy

Dysfunction of the immune system underlies a plethora of human diseases, requiring the development of immunomodulatory therapeutic intervention. To date, most strategies employed have been focusing on the modification of T lymphocytes, and although remarkable improvement has been obtained, results often fall short of the intended outcome. Recent cutting-edge technologies have highlighted macrophages as potential targets for disease control. Macrophages play central roles in development, homeostasis and host defence, and their dysfunction and dysregulation have been implicated in the onset and pathogenesis of multiple disorders including cancer, neurodegeneration, autoimmunity and metabolic diseases. Recent advancements have led to a greater understanding of macrophage origin, diversity and function, in both health and disease. Over the last few years, a variety of strategies targeting macrophages have been developed and these open new therapeutic opportunities. Here, we review the progress in macrophage reprogramming in various disorders and discuss the potential implications and challenges for macrophage-targeted approaches in human disease.

Is There a Place for Immune Checkpoint Inhibitors in Vulvar Neoplasms? A State of the Art Review

Vulvar cancer (VC) is a rare neoplasm, usually arising in postmenopausal women, although human papilloma virus (HPV)-associated VC usually develop in younger women. Incidences of VCs are rising in many countries. Surgery is the cornerstone of early-stage VC management, whereas therapies for advanced VC are multimodal and not standardized, combining chemotherapy and radiotherapy to avoid exenterative surgery. Randomized controlled trials (RCTs) are scarce due to the rarity of the disease and prognosis has not improved. Hence, new therapies are needed to improve the outcomes of these patients. In recent years, improved knowledge regarding the crosstalk between neoplastic and tumor cells has allowed researchers to develop a novel therapeutic approach exploiting these molecular interactions. Both the innate and adaptive immune systems play a key role in anti-tumor immunesurveillance. Immune checkpoint inhibitors (ICIs) have demonstrated efficacy in multiple tumor types, improving survival rates and disease outcomes. In some gynecologic cancers (e.g., cervical cancer), many studies are showing promising results and a growing interest is emerging about the potential use of ICIs in VC. The aim of this manuscript is to summarize the latest developments in the field of VC immunoncology, to present the role of state-of-the-art ICIs in VC management and to discuss new potential immunotherapeutic approaches.

Plasmacytoid Dendritic Cell (pDC) Infiltration Correlate with Tumor Infiltrating Lymphocytes, Cancer Immunity, and Better Survival in Triple Negative Breast Cancer (TNBC) More Strongly than Conventional Dendritic Cell (cDC)

Dendritic cells (DC) represent a major antigen-presenting cell type in the tumor immune microenvironment (TIME) and play an essential role in cancer immunity. Conventional DC (cDC) and plasmacytoid DC (pDC) were defined by the xCell algorithm and a total of 2968 breast cancer patients (TCGA and METABRIC) were analyzed. We found that triple-negative breast cancer (TNBC) had a high fraction of cDC and pDC compared to the other subtypes. In contrast to cDC, high pDC in TNBC was significantly associated with better disease-specific and disease-free survival consistently in both cohorts. High cDC TNBC tumors enriched not only inflammation and immune-related, but also metastasis-related gene sets in Gene Set Enrichment Analysis, whereas high pDC TNBC enriched inflammation and immune -related gene sets including IFN-γ signaling more strongly than cDC. pDC TNBC correlated with CD8+, CD4+ memory, IFN-γ score, and cytolytic activity stronger than cDC TNBC. High pDC TNBC were associated with a high fraction of anti-cancer immune cells and high expression of all the immune check point molecules examined. In conclusion, pDC levels correlated with the infiltration of immune cells and patient survival in TNBC more strongly than cDC; this is the first study suggesting the clinical relevance of pDC infiltration in TNBC.

Chemical Strategies to Boost Cancer Vaccines

Personalized cancer vaccines (PCVs) are reinvigorating vaccine strategies in cancer immunotherapy. In contrast to adoptive T-cell therapy and checkpoint blockade, the PCV strategy modulates the innate and adaptive immune systems with broader activation to redeploy antitumor immunity with individualized tumor-specific antigens (neoantigens). Following a sequential scheme of tumor biopsy, mutation analysis, and epitope prediction, the administration of neoantigens with synthetic long peptide (SLP) or mRNA formulations dramatically improves the population and activity of antigen-specific CD4+ and CD8+ T cells. Despite the promising prospect of PCVs, there is still great potential for optimizing prevaccination procedures and vaccine potency. In particular, the arduous development of tumor-associated antigen (TAA)-based vaccines provides valuable experience and rational principles for augmenting vaccine potency which is expected to advance PCV through the design of adjuvants, delivery systems, and immunosuppressive tumor microenvironment (TME) reversion since current personalized vaccination simply admixes antigens with adjuvants. Considering the broader application of TAA-based vaccine design, these two strategies complement each other and can lead to both personalized and universal therapeutic methods. Chemical strategies provide vast opportunities for (1) exploring novel adjuvants, including synthetic molecules and materials with optimizable activity, (2) constructing efficient and precise delivery systems to avoid systemic diffusion, improve biosafety, target secondary lymphoid organs, and enhance antigen presentation, and (3) combining bioengineering methods to innovate improvements in conventional vaccination, "smartly" re-educate the TME, and modulate antitumor immunity. As chemical strategies have proven versatility, reliability, and universality in the design of T cell- and B cell-based antitumor vaccines, the union of such numerous chemical methods in vaccine construction is expected to provide new vigor and vitality in cancer treatment.

Therapeutic Targeting of Signaling Pathways Related to Cancer Stemness

The theory of cancer stem cells (CSCs) proposes that the different cells within a tumor, as well as metastasis deriving from it, are originated from a single subpopulation of cells with self-renewal and differentiation capacities. These cancer stem cells are supposed to be critical for tumor expansion and metastasis, tumor relapse and resistance to conventional therapies, such as chemo- and radiotherapy. The acquisition of these abilities has been attributed to the activation of alternative pathways, for instance, WNT, NOTCH, SHH, PI3K, Hippo, or NF-κB pathways, that regulate detoxification mechanisms; increase the metabolic rate; induce resistance to apoptotic, autophagic, and senescence pathways; promote the overexpression of drug transporter proteins; and activate specific stem cell transcription factors. The elimination of CSCs is an important goal in cancer therapeutic approaches because it could decrease relapses and metastatic dissemination, which are main causes of mortality in oncology patients. In this work, we discuss the role of these signaling pathways in CSCs along with their therapeutic potential.

Recurrent vaginal intraepithelial neoplasia successfully treated with topical imiquimod: A case report

Vaginal intraepithelial neoplasia (VAIN) is a rare disease associated with human papillomavirus infection. High-grade VAIN is typically treated with either excisional or ablative therapy. However, recurrent VAIN lesions are common and these treatments cause vaginal scarring. Recent studies have indicated that 5% imiquimod is an effective treatment for VAIN. The present report describes a case of a woman diagnosed with recurrent VAIN 3 who was treated with a 5% topical imiquimod cream and achieved a complete response after excision and CO₂ laser vaporization. A 53-year-old, gravida 5, para 2 postmenopausal woman who was diagnosed with papillary squamous cell carcinoma by biopsy underwent conization, total abdominal hysterectomy and bilateral salpingo-oophorectomy. A histological examination revealed grade 3 cervical intraepithelial neoplasia with free surgical margins. At 3 years after the hysterectomy, the vaginal smear revealed atypical squamous cells, leading to a pathological diagnosis of VAIN 3. Partial vaginectomy was performed, and VAIN 3 was detected in the lesion with positive margins. At 4 months into follow-up, the vaginal smear revealed a high-grade squamous intraepithelial lesion (HSIL), and subsequent biopsy during colposcopy revealed a pathological diagnosis of VAIN 3. At 3 months after CO₂ laser vaporization, the vaginal smear revealed HSIL with suspected recurrence and imiquimod treatment was initiated. One sachet of 5% imiquimod cream (0.25 g) was placed in the entire vagina three times per week for 14 weeks with no apparent complications. At 3 years after the treatment, there has been no recurrence. This case demonstrated that topical imiquimod with careful follow-up is an effective treatment for VAIN and is well-tolerated. Further clinical evidence of the effectiveness and safety of imiquimod in patients diagnosed with VAIN is required.

Prognosis and targeting of pre-metastatic niche

As the main cause of tumoral fatality, metastasis remains to be one of the most urgent difficulties researcher struggled to overcome. During the development and progression of metastasis, the establishment of pre-metastatic niche is crucial in preparing fertile microenvironment for disseminated tumor cells settlement and colonization in distant metastatic target sites. The key participators, including the primary tumor-derived factors, bone marrow-derived cells, stromal cells of both the host and the potential metastatic sites, regulate the temporal progress of potential metastasis. Firstly, pioneers are sent from primary tumor, recruiting immunosuppressive cells; then circulating tumor cells settled and colonized; and finally, micrometastases develop. Here, we summarize the therapeutic strategies presented in recent years targeting different stages of the pre-metastatic niche formation and discuss their chances and challenges in clinical translation, providing promising approaches for metastasis prevention and therapeutic interventions.