Immune system and bone microenvironment: rationale for targeted cancer therapies

PD-L1 knockout or ZG16 overexpression inhibits PDAC progression and modulates TAM polarization

CRISPR/Cas9-mediated genome editing has the potential to delete PD-L1 both on the cell surface and inside the cell, thereby inhibiting tumor growth and migration and overcoming immunosuppression. ZG16, with its lectin structure, can reduce PD-L1 expression on the cell surface. However, direct comparison of two approaches on PD-L1 expression in Pancreatic ductal adenocarcinoma (PDAC) cells has not yet been investigated. In this study, we established two Panc-1 cell line: one with PD-L1 knockout and another with ZG16 overexpression. Both methods promoted the polarization of tumor-associated macrophages (TAMs) to the M1 phenotype, as indicated by increased levels of the M1 marker CD11c+ in vitro and in vivo. Meanwhile, we observed a reduction in the M2 marker CD206+, upregulation of immune activation-related cytokines/chemokines, and a decrease in immunosuppressive cytokines and tumor angiogenesis factors. In summary, both PD-L1 knockout and ZG16 overexpression represent promising approaches for PDAC treatment.

Immunotherapy in the Fight Against Bone Metastases: A Review of Recent Developments and Challenges

OPINION STATEMENT

Bone metastasis, a frequent and detrimental complication of advanced cancers, often triggers bone deterioration events that severely compromise patient quality of life and prognosis. The past few years have witnessed the emergence and continuous advancements in immunotherapy, ushering in innovative therapeutic prospects for bone metastasis. These advancements include not only the use of immune checkpoint inhibitors (ICIs), both as standalone and combined treatments, but also the investigation of novel targets within immune cells residing in bone metastases. These breakthroughs have instilled fresh optimism for effectively managing patients with bone metastasis. This article endeavors to present an exhaustive review of the recent progress made across a spectrum of immunotherapeutic strategies and targeted therapies specifically designed for individuals battling bone metastasis from malignant tumors. By doing so, it seeks to offer insights that can inform clinical practices and guide further medical research in this domain.

Unraveling the complexity of drug resistance mechanisms to SINE, T cell-engaging therapies and CELMoDs in multiple myeloma: a comprehensive review

Despite significant advances in the understanding of multiple myeloma (MM) biology and the development of novel treatment strategies in the last two decades, MM is still an incurable disease. Novel drugs with alternative mechanisms of action, such as selective inhibitors of nuclear export (SINE), modulators of the ubiquitin pathway [cereblon E3 ligase modulatory drugs (CELMoDs)], and T cell redirecting (TCR) therapy, have led to significant improvement in patient outcomes. However, resistance still emerges, posing a major problem for the treatment of myeloma patients. This review summarizes current data on treatment with SINE, TCR therapy, and CELMoDs and explores their mechanism of resistance. Understanding these resistance mechanisms is critical for developing strategies to overcome treatment failure and improve therapeutic outcomes.

Bone targeting agents, but not radiation therapy, improves survival in patients with bone metastases from advanced urothelial carcinoma receiving pembrolizumab: results from the ARON-2 study

The ARON-2 study (NCT05290038) aimed to assess the real-world efficacy of pembrolizumab in patients recurred or progressed after platinum-based chemotherapy. This retrospective analysis reports the outcomes of urothelial carcinoma (UC) patients with bone metastases (BM). Medical records of patients with documented metastatic UC treated by pembrolizumab as second-line therapy were reviewed from60 institutions in 20 countries. Patients were assessed for Overall Response Rate (ORR), Progression-Free Survival (PFS), and Overall Survival (OS). Univariate and multivariate analyses were used to explore the association of variables of interest with OS and PFS. 881 patients were included; of them, 263 (30%) presented BM. Median follow-up time was 22.7 months. Patients with BM showed both shorter median OS (5.9 months vs 13.1 months, p < 0.001) and PFS (3.5 months, vs 7.3 months, p < 0.001) compared to patients without BM. Patients who received bone targeted agents (BTAs) showed a significantly longer median OS (8.5 months vs 4.6 months, p = 0.003) and PFS (6.1 months vs 3.2 months, p = 0.003), while no survival benefits were observed among patients who received radiation therapy for BM during pembrolizumab treatment compared to those who did not. In multivariate analysis, performance status, concomitant liver metastases, and the lack of use of BTAs were significantly associated with worse OS and PFS. Bone involvement in UC patients treated with pembrolizumab predicts inferior survival. Poor performance status and liver metastases may further worsen outcomes, while the use of BTAs is associated with improved outcomes.

Breaking through Multiple Myeloma: A Paradigm for a Comprehensive Tumor Ecosystem Targeting

Multiple myeloma (MM) is a cancerous condition characterized by the proliferation of plasma cells within the hematopoietic marrow, resulting in multiple osteolytic lesions. MM patients typically experience bone pain, kidney damage, fatigue due to anemia, and infections. Historically, MM was an incurable disease with a life expectancy of around three years after diagnosis. However, over the past two decades, the development of novel therapeutics has significantly improved patient outcomes, including response to treatment, remission duration, quality of life, and overall survival. These advancements include thalidomide and its derivatives, lenalidomide and pomalidomide, which exhibit diverse mechanisms of action against the plasma cell clone. Additionally, proteasome inhibitors such as bortezomib, ixazomib, and carfilzomib disrupt protein degradation, proving specifically toxic to cancerous plasma cells. Recent advancements also involve monoclonal antibodies targeting surface antigens, such as elotuzumab (anti-CS1) and daratumumab (anti-CD38), bispecific t-cell engagers such as teclistamab (anti-BCMA/CD3) and Chimeric antigen receptor T (CAR-T)-based strategies, with a growing focus on drugs that exhibit increasingly targeted action against neoplastic plasma cells and relevant effects on the tumor microenvironment.

The Synthetic Collagen-Binding Peptide NIPEP-OSS Delays Mouse Myeloma Progression

Multiple myeloma (MM) is the second most common hematological malignancy. It is a clonal B-cell disorder characterized by the proliferation of malignant plasma cells in the bone marrow, the presence of monoclonal serum immunoglobulin, and osteolytic lesions. An increasing amount of evidence shows that the interactions of MM cells and the bone microenvironment play a significant role, suggesting that these interactions may be good targets for therapy. The osteopontin-derived collagen-binding motif-bearing peptide NIPEP-OSS stimulates biomineralization and enhances bone remodeling dynamics. Due to its unique targeted osteogenic activity with a broad safety margin, we evaluated the potential of NIPEP-OSS for anti-myeloma activity using MM bone disease (MMBD) animal models. In a 5TGM1-engrafted NSG model, the survival rates of the control and treated groups were significantly different (p = 0.0014), with median survival times of 45 and 57 days, respectively. The bioluminescence analyses showed that myeloma slowly developed in the treated mice compared to the control mice in both models. NIPEP-OSS enhanced bone formation by increasing biomineralization in the bone. We also tested NIPEP-OSS in a well-established 5TGM1-engrafted C57BL/KaLwRij model. Similar to the previous model, the median survival times of the control and treated groups were significantly different (p = 0.0057), with 46 and 63 days, respectively. In comparison with the control, an increase in p1NP was found in the treated mice. We concluded that NIPEP-OSS delays mouse myeloma progression via bone formation in MMBD mouse models.

Investigation of the Underlying Mechanism of Sclerosteosis Expression in Muscle Tissue in Multiple Myeloma with Sarcopenia

Objective

To explore the role of sclerosteosis (SOST) gene expression in the occurrence and development of multiple myeloma (MM) complicated with sarcopenia.

Methods

Analysis of the SOST expression in skeletal muscle tissue of patients with MM using high-throughput sequencing combined with transcriptomics; observation of morphological changes of the mouse C2C12 myoblasts co-cultured with SP2/0 myeloma cells in Transwell; observation of the SOST expression in the C2C12 myoblasts using the immunofluorescence labeling method; and assessment of the changes in exercise capacity of mice with MM using ethology; and the measurement of the SOST expression in muscles of mice using immunohistochemistry.

Results

The transcription level of the SOST gene in the muscle tissue was significantly higher in patients with MM and sarcopenia than in patients with MM without sarcopenia and elderly patients with sarcopenia; the area of C2C12 mouse myoblasts co-cultured with SP2/0 myeloma cells was 167,904 ± 8653.7 pix; this was significantly lower than the area of 402,994 ± 13,575.0 pix in the control group (CG); the fluorescence intensity of SOST in the cells of the experimental group (EG) was 159,389 ± 10,534 AU; this was significantly higher than the intensity of 26,338 ± 6059 AU in the CG; the differences in results of the coat-hanger test, the tail suspension test, the weight-bearing forced swimming test, and the grip strength test between the tumor-bearing mice in the EG and the CG were statistically significant; and the quantitative result of SOST expression in the muscle tissue of the EG mice was 11,515 ± 1573 pix; this was significantly higher than the result of 3399 ± 798.8 pix in the CG.

Conclusion

The SOST gene expression was significantly higher in muscle of mice in EG than in CG; and increased SOST gene expression might be a pathogenesis of MM complicated with sarcopenia.

Visualizing the Interactions Shaping the Imaging of the Microenvironment in Human Cancers

The Visium Spatial Gene Expression Solution (Visium 10×) allows for the mRNA analysis using high throughput sequencing and maps a transcriptional expression pattern in tissue sections using high-resolution microscope imaging in ex-vivo human and mice samples. The workflow surveys spatial global gene expression in tissue sections, exploiting the whole transcriptome profiling and defining the set of transcripts via targeted gene panels. An automated cell type annotation allows a comparison with control tissue samples. This technique delineates cancerous or diseased tissue boundaries and details gene expression gradients in the tissue surrounding the tumor or pathologic nests. Remarkably, the Visium 10× allows for whole transcriptome and targeted analysis without the loss of spatial information. This approach provides gene expression data within the context of tissue architecture, tissue microenvironments, and cell groups. It can be used in association with therapy, anti-angiogenic therapy, and immunotherapy to improve treatment response.

Mast Cells and Interleukins

Mast cells play a critical role in inflammatory diseases and tumor growth. The versatility of mast cells is reflected in their ability to secrete a wide range of biologically active cytokines, including interleukins, chemokines, lipid mediators, proteases, and biogenic amines. The aim of this review article is to analyze the complex involvement of mast cells in the secretion of interleukins and the role of interleukins in the regulation of biological activities of mast cells.

Pathways of Angiogenic and Inflammatory Cytokines in Multiple Myeloma: Role in Plasma Cell Clonal Expansion and Drug Resistance

Multiple myeloma (MM) is the second most common hematological malignancy, and despite the introduction of innovative therapies, remains an incurable disease. Identifying early and minimally or non-invasive biomarkers for predicting clinical outcomes and therapeutic responses is an active field of investigation. Malignant plasma cells (PCs) reside in the bone marrow (BM) microenvironment (BMME) which comprises cells (e.g., tumour, immune, stromal cells), components of the extracellular matrix (ECM) and vesicular and non-vesicular (soluble) molecules, all factors that support PCs’ survival and proliferation. The interaction between PCs and BM stromal cells (BMSCs), a hallmark of MM progression, is based not only on intercellular interactions but also on autocrine and paracrine circuits mediated by soluble or vesicular components. In fact, PCs and BMSCs secrete various cytokines, including angiogenic cytokines, essential for the formation of specialized niches called “osteoblastic and vascular niches”, thus supporting neovascularization and bone disease, vital processes that modulate the pathophysiological PCs–BMME interactions, and ultimately promoting disease progression. Here, we aim to discuss the roles of cytokines and growth factors in pathogenetic pathways in MM and as prognostic and predictive biomarkers. We also discuss the potential of targeted drugs that simultaneously block PCs’ proliferation and survival, PCs–BMSCs interactions and BMSCs activity, which may represent the future goal of MM therapy.

Preclinical Evaluation of CRISPR-Edited CAR-NK-92 Cells for Off-the-Shelf Treatment of AML and B-ALL

Acute myeloid leukemia (AML) and B-cell acute lymphocytic leukemia (B-ALL) are severe blood malignancies affecting both adults and children. Chimeric antigen receptor (CAR)-based immunotherapies have proven highly efficacious in the treatment of leukemia. However, the challenge of the immune escape of cancer cells remains. The development of more affordable and ready-to-use therapies is essential in view of the costly and time-consuming preparation of primary cell-based treatments. In order to promote the antitumor function against AML and B-ALL, we transduced NK-92 cells with CD276-CAR or CD19-CAR constructs. We also attempted to enhance cytotoxicity by a gene knockout of three different inhibitory checkpoints in NK cell function (CBLB, NKG2A, TIGIT) with CRISPR-Cas9 technology. The antileukemic activity of the generated cell lines was tested with calcein and luciferase-based cytotoxicity assays in various leukemia cell lines. Both CAR-NK-92 exhibited targeted cytotoxicity and a significant boost in antileukemic function in comparison to parental NK-92. CRISPR-Cas9 knock-outs did not improve B-ALL cytotoxicity. However, triple knock-out CD276-CAR-NK-92 cells, as well as CBLB or TIGIT knock-out NK-92 cells, showed significantly enhanced cytotoxicity against U-937 or U-937 CD19/tag AML cell lines. These results indicate that the CD19-CAR and CD276-CAR-NK-92 cell lines' cytotoxic performance is suitable for leukemia killing, making them promising off-the-shelf therapeutic candidates. The knock-out of CBLB and TIGIT in NK-92 and CD276-CAR-NK-92 should be further investigated for the treatment of AML.

Aplastic Anemia as a Roadmap for Bone Marrow Failure: An Overview and a Clinical Workflow

In recent years, it has become increasingly apparent that bone marrow (BM) failures and myeloid malignancy predisposition syndromes are characterized by a wide phenotypic spectrum and that these diseases must be considered in the differential diagnosis of children and adults with unexplained hematopoiesis defects. Clinically, hypocellular BM failure still represents a challenge in pathobiology-guided treatment. There are three fundamental topics that emerged from our review of the existing data. An exogenous stressor, an immune defect, and a constitutional genetic defect fuel a vicious cycle of hematopoietic stem cells, immune niches, and stroma compartments. A wide phenotypic spectrum exists for inherited and acquired BM failures and predispositions to myeloid malignancies. In order to effectively manage patients, it is crucial to establish the right diagnosis. New theragnostic windows can be revealed by exploring BM failure pathomechanisms.

Biological and Clinical Aspects of Metastatic Spinal Tumors

Simple Summary

Spine metastases are a common life-threatening complication of advanced-stage malignancies and often result in poor prognosis. Symptomatic spine metastases develop in the course of about 10% of malignant neoplasms. Therefore, it is essential for contemporary medicine to understand metastatic processes in order to find appropriate, targeted therapeutic options. Our literature review aimed to describe the up-to-date knowledge about the molecular pathways and biomarkers engaged in the spine’s metastatic processes. Moreover, we described current data regarding bone-targeted treatment, the emerging targeted therapies, radiotherapy, and immunotherapy used for the treatment of spine metastases. We hope that knowledge comprehensively presented in our review will contribute to the development of novel drugs targeting specific biomarkers and pathways. The more we learn about the molecular aspects of cancer metastasis, the easier it will be to look for treatment methods that will allow us to precisely kill tumor cells.

Abstract

Spine metastases are a common life-threatening complication of advanced-stage malignancies and often result in poor prognosis. Symptomatic spine metastases develop in the course of about 10% of malignant neoplasms. Therefore, it is essential for contemporary medicine to understand metastatic processes in order to find appropriate, targeted therapeutic options. Thanks to continuous research, there appears more and more detailed knowledge about cancer and metastasis, but these transformations are extremely complicated, e.g., due to the complexity of reactions, the variety of places where they occur, or the participation of both tumor cells and host cells in these transitions. The right target points in tumor metastasis mechanisms are still being researched; that will help us in the proper diagnosis as well as in finding the right treatment. In this literature review, we described the current knowledge about the molecular pathways and biomarkers engaged in metastatic processes involving the spine. We also presented a current bone-targeted treatment for spine metastases and the emerging therapies targeting the discussed molecular mechanisms.

Drug resistance in multiple myeloma: Soldiers and weapons in the bone marrow niche

Multiple myeloma (MM) is still an incurable disease, despite considerable improvements in treatment strategies, as resistance to most currently available agents is not uncommon. In this study, data on drug resistance in MM were analyzed and led to the following conclusions: resistance occurs via intrinsic and extrinsic mechanisms, including intraclonal heterogeneity, drug efflux pumps, alterations of drug targets, the inhibition of apoptosis, increased DNA repair and interactions with the bone marrow (BM) microenvironment, cell adhesion, and the release of soluble factors. Since MM involves the BM, interactions in the MM-BM microenvironment were examined as well, with a focus on the cross-talk between BM stromal cells (BMSCs), adipocytes, osteoclasts, osteoblasts, endothelial cells, and immune cells. Given the complex mechanisms that drive MM, next-generation treatment strategies that avoid drug resistance must target both the neoplastic clone and its non-malignant environment. Possible approaches based on recent evidence include: (i) proteasome and histone deacetylases inhibitors that not only target MM but also act on BMSCs and osteoclasts; (ii) novel peptide drug conjugates that target both the MM malignant clone and angiogenesis to unleash an effective anti-MM immune response. Finally, the role of cancer stem cells in MM is unknown but given their roles in the development of solid and hematological malignancies, cancer relapse, and drug resistance, their identification and description are of paramount importance for MM management.

Epigenetic regulation of angiogenesis in tumor progression

Epigenetic is the study of those alterations regulating gene expression without altering DNA sequence and inherited by transmission through cell division. DNA hypomethylation, hypermethylation of tumor suppressor genes, aberrant histone modifications and/or specific microRNAs expression profiles contribute to tumor initiation and progression. In this review, we will discuss the role of epigenetic changes in the regulation of tumor angiogenesis.

SARS-CoV-2 and Endothelial Cells: Vascular Changes, Intussusceptive Microvascular Growth and Novel Therapeutic Windows

Endothelial activation in infectious diseases plays a crucial role in understanding and predicting the outcomes and future treatments of several clinical conditions. COVID-19 is no exception. Moving from basic principles to novel approaches, an evolving view of endothelial activation provides insights into a better knowledge of the upstream actors in COVID-19 as a crucial future direction for managing SARS-CoV-2 and other infections. Assessing the function of resting and damaged endothelial cells in infection, particularly in COVID-19, five critical processes emerged controlling thrombo-resistance: vascular integrity, blood flow regulation, immune cell trafficking, angiogenesis and intussusceptive microvascular growth. Endothelial cell injury is associated with thrombosis, increased vessel contraction and a crucial phenomenon identified as intussusceptive microvascular growth, an unprecedented event of vessel splitting into two lumens through the integration of circulating pro-angiogenic cells. An essential awareness of endothelial cells and their phenotypic changes in COVID-19 inflammation is pivotal to understanding the vascular biology of infections and may offer crucial new therapeutic windows.

Bioinformatics Analysis of the Key Genes and Pathways in Multiple Myeloma

Objective

To study the differentially expressed genes between multiple myeloma and healthy whole blood samples by bioinformatics analysis, find out the key genes involved in the occurrence, development and prognosis of multiple myeloma, and analyze and predict their functions.

Methods

The gene chip data GSE146649 was downloaded from the GEO expression database. The gene chip data GSE146649 was analyzed by R language to obtain the genes with different expression in multiple myeloma and healthy samples, and the cluster analysis heat map was constructed. At the same time, the protein-protein interaction (PPI) networks of these DEGs were established by STRING and Cytoscape software. The gene co-expression module was constructed by weighted correlation network analysis (WGCNA). The hub genes were identified from key gene and central gene. TCGA database was used to analyze the expression of differentially expressed genes in patients with multiple myeloma. Finally, the expression level of TNFSF11 in whole blood samples from patients with multiple myeloma was analyzed by RT qPCR.

Results

We identified four genes (TNFSF11, FGF2, SGMS2, IGFBP7) as hub genes of multiple myeloma. Then, TCGA database was used to analyze the survival of TNFSF11, FGF2, SGMS2 and IGFBP7 in patients with multiple myeloma. Finally, the expression level of TNFSF11 in whole blood samples from patients with multiple myeloma was analyzed by RT qPCR.

Conclusion

The study suggests that TNFSF11, FGF2, SGMS2 and IGFBP7 are important research targets to explore the pathogenesis, diagnosis and treatment of multiple myeloma.

LTβR overexpression promotes plasma cell accumulation

Multiple myeloma (MM), a malignancy of plasma cells (PCs), has diverse genetic underpinnings and in rare cases these include amplification of the lymphotoxin b receptor (Ltbr) locus. LTβR has well defined roles in supporting lymphoid tissue development and function through actions in stromal and myeloid cells, but whether it is functional in PCs is unknown. Here we showed that Ltbr mRNA was upregulated in mouse PCs compared to follicular B cells, but deficiency in the receptor did not cause a reduction in PC responses to a T-dependent or T-independent immunogen. However, LTβR overexpression (OE) enhanced PC formation in vitro after LPS or anti-CD40 stimulation. In vivo, LTβR OE led to increased antigen-specific splenic and bone marrow (BM) plasma cells responses. LTβR OE PCs had increased expression of Nfkb2 and of the NF-kB target genes Bcl2 and Mcl1, factors involved in the formation of long-lived BM PCs. Our findings suggest a pathway by which Ltbr gene amplifications may contribute to MM development through increased NF-kB activity and induction of an anti-apoptotic transcriptional program.

The Route of the Malignant Plasma Cell in Its Survival Niche: Exploring “Multiple Myelomas”

Growing evidence points to multiple myeloma (MM) and its stromal microenvironment using several mechanisms to subvert effective immune and anti-tumor responses. Recent advances have uncovered the tumor-stromal cell influence in regulating the immune-microenvironment and have envisioned targeting these suppressive pathways to improve therapeutic outcomes. Nevertheless, some subgroups of patients include those with particularly unfavorable prognoses. Biological stratification can be used to categorize patient-, disease- or therapy-related factors, or alternatively, these biological determinants can be included in a dynamic model that customizes a given treatment to a specific patient. Genetic heterogeneity and current knowledge enforce a systematic and comprehensive bench-to-bedside approach. Given the increasing role of cancer stem cells (CSCs) in better characterizing the pathogenesis of solid and hematological malignancies, disease relapse, and drug resistance, identifying and describing CSCs is of paramount importance in the management of MM. Even though the function of CSCs is well-known in other cancer types, their role in MM remains elusive. With this review, we aim to provide an update on MM homing and resilience in the bone marrow micro milieu. These data are particularly interesting for clinicians facing unmet medical needs while designing novel treatment approaches for MM.

Methyladenosine Modification in RNAs: From Regulatory Roles to Therapeutic Implications in Cancer

Simple Summary

Cancer remains a burden to the public health all over the world. An increasing number of studies have concentrated on the role of methyladenosine modifications on cancers. Methyladenosine modifications mainly include N6-methyladenosine (m⁶A), N1-methyladenosine (m¹A), and 2’-O-methyladenosine (m⁶A_m), of which dynamic changes could modulate the metabolism of RNAs in eukaryotic cells. Mounting evidence has confirmed the crucial role of methyladenosine modification in cancer, offering possibilities for cancer therapy. In this review, we discussed the regulatory role of methyladenosine modification on cancer, as well as their potential for treatment.

Abstract

Methyladenosine modifications are the most abundant RNA modifications, including N6-methyladenosine (m⁶A), N1-methyladenosine (m¹A), and 2’-O-methyladenosine (m⁶A_m). As reversible epigenetic modifications, methyladenosine modifications in eukaryotic RNAs are not invariable. Drastic alterations of m⁶A are found in a variety of diseases, including cancers. Dynamic changes of m⁶A modification induced by abnormal methyltransferase, demethylases, and readers can regulate cancer progression via interfering with the splicing, localization, translation, and stability of mRNAs. Meanwhile, m⁶A, m¹A, and m⁶A_m modifications also exert regulatory effects on noncoding RNAs in cancer progression. In this paper, we reviewed recent findings concerning the underlying biomechanism of methyladenosine modifications in oncogenesis and metastasis and discussed the therapeutic potential of methyladenosine modifications in cancer treatments.

Bone Metastasis and Immune Checkpoint Inhibitors in Non-Small Cell Lung Cancer (NSCLC): Microenvironment and Possible Clinical Implications

Patients with non-small cell lung cancer (NSCLC) develop bone metastasis (BoM) in more than 50% of cases during the course of the disease. This metastatic site can lead to the development of skeletal related events (SREs), such as severe pain, pathological fractures, spinal compression, and hypercalcemia, which reduce the patient’s quality of life. Recently, the treatment of advanced NSCLC has radically changed due to the advent of immunotherapy. Immune checkpoint inhibitors (ICI) alone or in combination with chemotherapy have become the main therapeutic strategy for advanced or metastatic NSCLC without driver gene mutations. Since survival has increased, it has become even more important to treat bone metastasis to prevent SRE. We know that the presence of bone metastasis is a negative prognostic factor. The lower efficacy of immunotherapy treatments in BoM+ patients could be induced by the presence of a particular immunosuppressive tumor and bone microenvironment. This article reviews the most important pre-clinical and clinical scientific evidence on the reasons for this lower sensitivity to immunotherapy and the need to combine bone target therapies (BTT) with immunotherapy to improve patient outcome.

A Challenging Case of Visceral Leishmaniasis

The term leishmaniasis includes multiple clinical syndromes: visceral, cutaneous, and mucosal leishmaniasis, resulting from an infection of macrophages throughout the reticuloendothelial system in the dermis and the naso-oropharyngeal mucosa, respectively. The clinical phenotype is mainly driven by the leishmania biologic characteristics and, ultimately, also by the host immune status. The disease is endemic in focal areas in the tropics, subtropics, and southern Europe, transmitted by the bite of female phlebotomine sandflies. Sandflies regurgitate the parasite’s flagellated promastigote stage into the host’s skin; promastigotes bind to receptors on macrophages are phagocytized and transformed within phagolysosomes into non-flagellated amastigotes which replicate and infect additional macrophages. Amastigotes ingested by sandflies transform back into infective promastigotes. Depending on the host’s innate and acquired immune status, systemic and visceral leishmaniasis can be characterized by irregular fever, weight loss, enlargement of the spleen and liver, and anaemia. We present a 42 year-old man with long-lasting type 1 autoimmune hepatitis under immunosuppressive treatment. In January 2017, the patient started to experience low-grade unresponsiveness to empiric antibiotic therapy. The patient developed severe anemia and progressive multilineage cytopenia accompanied by increased levels of inflammatory markers. FDG-PET revealed increased glucose uptake in the liver, spleen, and the whole bone marrow. The subsequently performed bone marrow biopsy evidenced Leishmania amastigotes inside macrophages, confirmed by serological positivity to anti-Leishmania antibody. Immunosuppressive therapy was suspended and replaced by treatment with amphotericin B at 4 mg/kg/day from day 1 to day 5, followed by a single infusion on days 10, 17, 24, 31, and 38. The bone marrow smear after treatment still evidenced few Leishmania amastigotes; in consideration of the patient’s immunosuppression status, two further doses of amphotericin B on days 45 and 52 were employed, leading to infection resolution. In real-life, as exemplified in this case, administering two additional doses of amphotericin B (concerning the guidelines) offered an additional therapeutic opportunity for a patient under long-term immunosuppressive treatment.

mTORC1-Inhibition Potentiating Metabolic Block by Tyrosine Kinase Inhibitor Ponatinib in Multiple Myeloma

Simple Summary

From a screen for metabolic inhibition by a panel of approved anticancer drugs and combining the lead compound with a mammalian target of rapamycin complex 1 (mTORC1) inhibitor, we demonstrated that the combination of ponatinib and sirolimus leads to synergistic tumor growth inhibition in a mouse xenograft tumor model of multiple myeloma. The rationale of combining the two drugs was to prevent metabolic escape due to glycolysis reprogramming and residual oxidative phosphorylation (OXPHOS). The robust increases in reactive oxygen species (ROS) due to a block in glycolysis were shown to be the lead contributor of cell viability loss. The drug combination in the doses used displayed no overt toxicity in the treated animals.

Abstract

Studies in targeting metabolism in cancer cells have shown the flexibility of cells in reprogramming their pathways away from a given metabolic block. Such behavior prompts a combination drug approach in targeting cancer metabolism, as a single compound may not address the tumor intractability. Overall, mammalian target of rapamycin complex 1 (mTORC1) signaling has been implicated as enabling metabolic escape in the case of a glycolysis block. From a library of compounds, the tyrosine kinase inhibitor ponatinib was screened to provide optimal reduction in metabolic activity in the production of adenosine triphosphate (ATP), pyruvate, and lactate for multiple myeloma cells; however, these cells displayed increasing levels of oxidative phosphorylation (OXPHOS), enabling them to continue generating ATP, although at a slower pace. The combination of ponatinib with the mTORC1 inhibitor, sirolimus, blocked OXPHOS; an effect also manifested in activity reductions for hexokinase 2 (HK2) and glucose-6-phosphate isomerase (GPI) glycolysis enzymes. There were also remarkably higher levels of reactive oxygen species (ROS) produced in mouse xenografts, on par with increased glycolytic block. The combination of ponatinib and sirolimus resulted in synergistic inhibition of tumor xenografts with no overt toxicity in treated mice for kidney and liver function or maintaining weight.

Transforming Growth Factor-Beta Orchestrates Tumour and Bystander Cells in B-Cell Non-Hodgkin Lymphoma

Transforming growth factor-beta (TGFB) is a critical regulator of normal haematopoiesis. Dysregulation of the TGFB pathway is associated with numerous haematological malignancies including myelofibrosis, acute myeloid leukaemia, and lymphoid disorders. TGFB has classically been seen as a negative regulator of proliferation in haematopoiesis whilst stimulating differentiation and apoptosis, as required to maintain homeostasis. Tumours frequently develop intrinsic resistant mechanisms to homeostatic TGFB signalling to antagonise its tumour-suppressive functions. Furthermore, elevated levels of TGFB enhance pathogenesis through modulation of the immune system and tumour microenvironment. Here, we review recent advances in the understanding of TGFB signalling in B-cell malignancies with a focus on the tumour microenvironment. Malignant B-cells harbour subtype-specific alterations in TGFB signalling elements including downregulation of surface receptors, modulation of SMAD signalling proteins, as well as genetic and epigenetic aberrations. Microenvironmental TGFB generates a protumoural niche reprogramming stromal, natural killer (NK), and T-cells. Increasingly, evidence points to complex bi-directional cross-talk between cells of the microenvironment and malignant B-cells. A greater understanding of intercellular communication and the context-specific nature of TGFB signalling may provide further insight into disease pathogenesis and future therapeutic strategies.

Angiogenesis as Therapeutic Target in Metastatic Prostate Cancer - Narrowing the Gap Between Bench and Bedside

Angiogenesis in metastatic castration-resistant prostate cancer (mCRPC) has been extensively investigated as a promising druggable biological process. Nonetheless, targeting angiogenesis has failed to impact overall survival (OS) in patients with mCRPC despite promising preclinical and early clinical data. This discrepancy prompted a literature review highlighting the tumor heterogeneity and biological context of Prostate Cancer (PCa). Narrowing the gap between the bench and bedside appears critical for developing novel therapeutic strategies. Searching clinicaltrials.gov for studies examining angiogenesis inhibition in patients with PCa resulted in n=20 trials with specific angiogenesis inhibitors currently recruiting (as of September 2021). Moreover, several other compounds with known anti-angiogenic properties - such as Metformin or Curcumin - are currently investigated. In general, angiogenesis-targeting strategies in PCa include biomarker-guided treatment stratification - as well as combinatorial approaches. Beyond established angiogenesis inhibitors, PCa therapies aiming at PSMA (Prostate Specific Membrane Antigen) hold the promise to have a substantial anti-angiogenic effect - due to PSMA´s abundant expression in tumor vasculature.

Immune Checkpoint Inhibitor Therapy for Bone Metastases: Specific Microenvironment and Current Situation

The treatment of bone metastases is a thorny issue. Immunotherapy may be one of the few hopes for patients with unresectable bone metastases. Immune checkpoint inhibitors are the most commonly used immunotherapy drugs currently. In this review, the characteristics and interaction of bone metastases and their immune microenvironment were systematically discussed, and the relevant research progress of the immunological mechanism of tumor bone metastasis was reviewed. On this basis, we expounded the clinical application of immune checkpoint inhibitors for bone metastasis of common tumors, including non-small-cell lung cancer, renal cell carcinoma, prostate cancer, melanoma, and breast cancer. Then, the deficiencies and limitations in current researches were summarized. In-depth basic research on bone metastases and optimization of clinical treatment is needed.

Case Report: Evolution of a Severe Vascular Refractory Form of ECD Requiring Liver Transplantation Correlated With the Change in the Monocyte Subset Analysis

Erdheim–Chester disease is a rare histiocytosis characterized by iconic features associated with compatible histology. Most patients have somatic mutations in the MAP-kinase pathway gene, and the mutations occur in CD14⁺ monocytes. Differentiation of the myeloid lineage plays a central role in the pathogenesis of histiocytosis. Monocytes are myeloid-derived white blood cells, divided into three subsets, but only the CD14⁺⁺CD16⁻ “classical monocyte” can differentiate into dendritic cells and tissue macrophages. Since most mutations occur in CD14⁺ cells and since ECD patients have a particular monocytic phenotype resembling CMML, we studied the correlation between disease activity and monocytic subset distribution during the course of a severe vascular form of ECD requiring liver transplantation. During early follow-up, increased CD14⁺⁺CD16⁻ “classical monocyte” associated with decreased CD14^lowCD16⁺⁺ “non-classical monocyte” correlated with disease activity. Further studies are needed to confirm the use of monocyte as a marker of disease activity in patients with ECD.

New insights into the biomimetic design and biomedical applications of bioengineered bone microenvironments

The bone microenvironment is characterized by an intricate interplay between cellular and noncellular components, which controls bone remodeling and repair. Its highly hierarchical architecture and dynamic composition provide a unique microenvironment as source of inspiration for the design of a wide variety of bone tissue engineering strategies. To overcome current limitations associated with the gold standard for the treatment of bone fractures and defects, bioengineered bone microenvironments have the potential to orchestrate the process of bone regeneration in a self-regulated manner. However, successful approaches require a strategic combination of osteogenic, vasculogenic, and immunomodulatory factors through a synergic coordination between bone cells, bone-forming factors, and biomaterials. Herein, we provide an overview of (i) current three-dimensional strategies that mimic the bone microenvironment and (ii) potential applications of bioengineered microenvironments. These strategies range from simple to highly complex, aiming to recreate the architecture and spatial organization of cell-cell, cell-matrix, and cell-soluble factor interactions resembling the in vivo microenvironment. While several bone microenvironment-mimicking strategies with biophysical and biochemical cues have been proposed, approaches that exploit the ability of the cells to self-organize into microenvironments with a high regenerative capacity should become a top priority in the design of strategies toward bone regeneration. These miniaturized bone platforms may recapitulate key characteristics of the bone regenerative process and hold great promise to provide new treatment concepts for the next generation of bone implants.

Detection of Metastatic Tumor Cells in the Bone Marrow Aspirate Smears by Artificial Intelligence (AI)-Based Morphogo System

Introduction

Metastatic carcinomas of bone marrow (MCBM) are characterized as tumors of non-hematopoietic origin spreading to the bone marrow through blood or lymphatic circulation. The diagnosis is critical for tumor staging, treatment selection and prognostic risk stratification. However, the identification of metastatic carcinoma cells on bone marrow aspiration smears is technically challenging by conventional microscopic screening.

Objective

The aim of this study is to develop an automatic recognition system using deep learning algorithms applied to bone marrow cells image analysis. The system takes advantage of an artificial intelligence (AI)-based method in recognizing metastatic atypical cancer clusters and promoting rapid diagnosis.

Methods

We retrospectively reviewed metastatic non-hematopoietic malignancies in bone marrow aspirate smears collected from 60 cases of patients admitted to Zhongshan Hospital. High resolution digital bone marrow aspirate smear images were generated and automatically analyzed by Morphogo AI based system. Morphogo system was trained and validated using 20748 cell cluster images from randomly selected 50 MCBM patients. 5469 pre-classified cell cluster images from the remaining 10 MCBM patients were used to test the recognition performance between Morphogo and experienced pathologists.

Results

Morphogo exhibited a sensitivity of 56.6%, a specificity of 91.3%, and an accuracy of 82.2% in the recognition of metastatic cancer cells. Morphogo’s classification result was in general agreement with the conventional standard in the diagnosis of metastatic cancer clusters, with a Kappa value of 0.513. The test results between Morphogo and pathologists H1, H2 and H3 agreement demonstrated a reliability coefficient of 0.827. The area under the curve (AUC) for Morphogo to diagnose the cancer cell clusters was 0.865.

Conclusion

In patients with clinical history of cancer, the Morphogo system was validated as a useful screening tool in the identification of metastatic cancer cells in the bone marrow aspirate smears. It has potential clinical application in the diagnostic assessment of metastatic cancers for staging and in screening MCBM during morphology examination when the symptoms of the primary site are indolent.

The Clinical Characteristics and Prognostic Nomogram for Head and Neck Cancer Patients with Bone Metastasis

Background

Head and neck cancer (HNC) is the sixth most common malignancy globally, and many demographics and clinicopathological factors influence its prognosis. This study aimed to construct and validate a prognostic nomogram to predict the prognosis of HNC patients with bone metastasis (BM).

Methods

A total of 326 patients with BM from HNC were collected from the SEER database as the subjects of this study. In a ratio of 7 to 3, patients were randomly divided into training and validation groups. Independent prognostic factors for HNC patients with BM were identified by univariate and multivariate Cox regression analysis. The nomogram for predicting the prognosis was constructed, and the model was evaluated by receiver operating characteristic curves, calibration curves, and decision curve analysis.

Result

The independent prognostic factors for HNC patients with BM included age, primary site, lung metastasis, and chemotherapy. The area under the curve predicting overall survival at 12, 24, and 36 months was 0.768, 0.747, and 0.723 in the training group and 0.729, 0.723, and 0.669 in the validation group, respectively. The calibration curves showed good agreement between the predicted and actual values for overall survival. In addition, the decision curve analysis showed that this prognostic nomogram model has a high clinical application.

Conclusion

This study developed and validated a nomogram to predict overall survival in HNC patients with BM. The prognostic nomogram has high accuracy and utility to inform survival estimation and individualized treatment decisions.

Advanced Flow Cytometry Analysis Algorithms for Optimizing the Detection of "Different From Normal" Immunophenotypes in Acute Myeloid Blasts

Acute myeloid leukemias (AMLs) are a group of hematologic malignancies that are heterogeneous in their molecular and immunophenotypic profiles. Identification of the immunophenotypic differences between AML blasts and normal myeloid hematopoietic precursors (myHPCs) is a prerequisite to achieving better performance in AML measurable residual disease follow-ups. In the present study, we applied high-dimensional analysis algorithms provided by the Infinicyt 2.0 and Cytobank software to evaluate the efficacy of antibody combinations of the EuroFlow AML/myelodysplastic syndrome panel to distinguish AML blasts with recurrent genetic abnormalities (n = 39 AML samples) from normal CD45low CD117+ myHPCs (n = 23 normal bone marrow samples). Two types of scores were established to evaluate the abilities of the various methods to identify the most useful parameters/markers for distinguishing between AML blasts and normal myHPCs, as well as to distinguish between different AML groups. The Infinicyt Compass database-guided analysis was found to be a more user-friendly tool than other analysis methods implemented in the Cytobank software. According to the developed scoring systems, the principal component analysis based algorithms resulted in better discrimination between AML blasts and myHPCs, as well as between blasts from different AML groups. The most informative markers for the discrimination between myHPCs and AML blasts were CD34, CD36, human leukocyte antigen-DR (HLA-DR), CD13, CD105, CD71, and SSC, which were highly rated by all evaluated analysis algorithms. The HLA-DR, CD34, CD13, CD64, CD33, CD117, CD71, CD36, CD11b, SSC, and FSC were found to be useful for the distinction between blasts from different AML groups associated with recurrent genetic abnormalities. This study identified both benefits and the drawbacks of integrating multiple high-dimensional algorithms to gain complementary insights into the flow-cytometry data.

Clinical Discernment, Bone Marrow, and Molecular Diagnostics Are Equally Important to Solve the Phenotypic Mimicry among Subtypes of Myeloproliferative Neoplasms

The 2016 WHO classification integrates clinical, bone marrow (BM)-morphology, and molecular features to define disease entities. This together with the advancements in molecular detection and standardization of BM features enable an accurate diagnosis of myeloproliferative neoplasms (MPN) in the majority of patients. Diagnostic challenges remain due to phenotypic mimicry of MPN, failing specificity of BM-morphology, and the fact that phenotype-driver mutations, such as JAK2V617F, are not exclusive to a particular MPN, and their absence does not preclude any of these. We present a series of cases to illustrate themes to be considered in complex cases of MPN, such as triple-negative (TN)-MPN or MPN-unclassifiable (MPN-U). Eleven patients labelled as TN-MPN or MPN-U were included. Serum tryptase and NGS were part of a systematic/sequential multidisciplinary evaluation. Results were clustered into four categories based on diagnostic entities and/or how these diagnoses were made: (A) With expanding molecular techniques, BCR-ABL1 and karyotyping should not be missed; (B) systemic mastocytosis is underdiagnosed and often missed; (C) benign non-clonal disorders could mimic MPN; and (D) NGS could prove clonality in some “TN”-MPN cases. The prognostic/therapeutic consequences of an accurate diagnosis are immense. In TN-MPN or MPN-U cases, a multidisciplinary re-evaluation integrating molecular results, BM-morphology, and clinical judgment is crucial.

An Improved Animal Model of Multiple Myeloma Bone Disease

Multiple myeloma (MM) is a plasma cell malignancy that causes an accumulation of terminally differentiated monoclonal plasma cells in the bone marrow, accompanied by multiple myeloma bone disease (MMBD). MM animal models have been developed and enable to interrogate the mechanism of MM tumorigenesis. However, these models demonstrate little or no evidence of MMBD. We try to establish the MMBD model with severe bone lesions and easily accessible MM progression. 1 × 106 luciferase-expressing 5TGM1 cells were injected into 8-12 week-old NOD SCID gamma mouse (NSG) and C57BL/KaLwRij mouse via the tail vein. Myeloma progression was assessed weekly via in vivo bioluminescence (BL) imaging using IVIS-200. The spine and femur/tibia were extracted and scanned by the micro-computer tomography for bone histo-morphometric analyses at the postmortem. The median survivals were 56 days in NSG while 44.5 days in C57BL/KaLwRij agreed with the BL imaging results. Histomorphic and DEXA analyses demonstrated that NSG mice have severe bone resorption that occurred at the lumbar spine but no significance at the femur compared to C57BL/KaLwRij mice. Based on these, we conclude that the systemic 5TGM1 injected NSG mouse slowly progresses myeloma and develops more severe MMBD than the C57BL/KaLwRij model.

Adipsin-Dependent Secretion of Hepatocyte Growth Factor Regulates the Adipocyte-Cancer Stem Cell Interaction

Simple Summary

Obesity, which is characterized by the excess of adipose tissue, is associated with an increased risk of multiple cancers. We have previously reported that adipsin, a secreted factor from adipocytes, enhances cancer cell proliferation and stem cell properties. In this study, we found that adipsin affected adipocytes themselves and enhanced their secretion of hepatocyte growth factor (HGF). We found that HGF enhanced the adipocyte-cancer cell interactions as a downstream effector of adipsin. Understanding the adipocyte-cancer cell interaction will provide a novel strategy to treat cancers whose initiation, invasion, and metastatic progression are associated with adipose tissues.

Abstract

Adipose tissue is a component of the tumor microenvironment and is involved in tumor progression. We have previously shown that adipokine adipsin (CFD) functions as an enhancer of tumor proliferation and cancer stem cell (CSC) properties in breast cancers. We established the Cfd-knockout (KO) mice and the mammary adipose tissue-derived stem cells (mADSCs) from them. Cfd-KO in mADSCs significantly reduced their ability to enhance tumorsphere formation of breast cancer patient-derived xenograft (PDX) cells, which was restored by the addition of Cfd in the culture medium. Hepatocyte growth factor (HGF) was expressed and secreted from mADSCs in a Cfd-dependent manner. HGF rescued the reduced ability of Cfd-KO mADSCs to promote tumorsphere formation in vitro and tumor formation in vivo by breast cancer PDX cells. These results suggest that HGF is a downstream effector of Cfd in mADSCs that enhances the CSC properties in breast cancers.

The Anti-VEGF(R) Drug Discovery Legacy: Improving Attrition Rates by Breaking the Vicious Cycle of Angiogenesis in Cancer

Resistance to anti-vascular endothelial growth factor (VEGF) molecules causes lack of response and disease recurrence. Acquired resistance develops as a result of genetic/epigenetic changes conferring to the cancer cells a drug resistant phenotype. In addition to tumor cells, tumor endothelial cells also undergo epigenetic modifications involved in resistance to anti-angiogenic therapies. The association of multiple anti-angiogenic molecules or a combination of anti-angiogenic drugs with other treatment regimens have been indicated as alternative therapeutic strategies to overcome resistance to anti-angiogenic therapies. Alternative mechanisms of tumor vasculature, including intussusceptive microvascular growth (IMG), vasculogenic mimicry, and vascular co-option, are involved in resistance to anti-angiogenic therapies. The crosstalk between angiogenesis and immune cells explains the efficacy of combining anti-angiogenic drugs with immune check-point inhibitors. Collectively, in order to increase clinical benefits and overcome resistance to anti-angiogenesis therapies, pan-omics profiling is key.

Cancer Treatment-Induced Bone Loss (CTIBL): State of the Art and Proper Management in Breast Cancer Patients on Endocrine Therapy

OPINION STATEMENT

About 70-80% of early breast cancer (BC) patients receive adjuvant endocrine therapy (ET) for at least 5 years. ET includes in the majority of cases the use of aromatase inhibitors, as upfront or switch strategy, that lead to impaired bone health. Given the high incidence and also the high prevalence of BC, cancer treatment-induced bone loss (CTIBL) represents the most common long-term adverse event experimented by patients with hormone receptor positive tumours. CTIBL is responsible for osteoporosis occurrence and, as a consequence, fragility fractures that may negatively affect quality of life and survival expectancy. As recommended by main international guidelines, BC women on aromatase inhibitors should be carefully assessed for their fracture risk at baseline and periodically reassessed during adjuvant ET in order to early detect significant worsening in terms of bone health. Antiresorptive agents, together with adequate intake of calcium and vitamin D, should be administered in BC patients during all course of ET, especially in those at high risk of osteoporotic fractures, as calculated by tools available for clinicians. Bisphosphonates, such as zoledronate or pamidronate, and anti-RANKL antibody, denosumab, are the two classes of antiresorptive drugs used in clinical practice with similar efficacy in preventing bone loss induced by aromatase inhibitor therapy. The choice between them, in the absence of direct comparison, should be based on patients' preference and compliance; the different safety profile is mainly related to the route of administration, although both types of drugs are manageable with due care, since most of the adverse events are predictable and preventable. Despite advances in management of CTIBL, several issues such as the optimal time of starting antiresorptive agents and the duration of treatment remain unanswered. Future clinical trials as well as increased awareness of bone health are needed to improve prevention, assessment and treatment of CTIBL in these long-term survivor patients.

Pancreatic Cancer Signaling Pathways, Genetic Alterations, and Tumor Microenvironment: The Barriers Affecting the Method of Treatment

Genetic alterations, especially the K-Ras mutation, carry the heaviest burden in the progression of pancreatic precursor lesions into pancreatic ductal adenocarcinoma (PDAC). The tumor microenvironment is one of the challenges that hinder the therapeutic approaches from functioning sufficiently and leads to the immune evasion of pancreatic malignant cells. Mastering the mechanisms of these two hallmarks of PDAC can help us in dealing with the obstacles in the way of treatment. In this review, we have analyzed the signaling pathways involved in PDAC development and the immune system's role in pancreatic cancer and immune checkpoint inhibition as next-generation therapeutic strategy. The direct targeting of the involved signaling molecules and the immune checkpoint molecules, along with a combination with conventional therapies, have reached the most promising results in pancreatic cancer treatment.

Prognostic Value of the Pretreatment Systemic Immune-Inflammation Index in Patients with Colorectal Cancer

Background

Multiple studies have reported the significance of the systemic immune-inflammation index (SII) in the prognosis of colorectal cancer (CRC), but no consensus has yet been reached. The purpose of this study was to systematically assess the prognostic value of SII in patients with CRC.

Materials and Methods

We performed a systematic literature search in PubMed, Embase, and the Cochrane Library for eligible studies. The correlation between pretreatment SII and overall survival (OS), disease-free survival (DFS), and progression-free survival (PFS) in CRC patients was evaluated by combining the hazard ratio (HR) and 95% confidence interval (CI).

Results

Twelve studies involving 3919 patients were included. Comprehensive analysis results showed that high SII indicated poor OS in CRC patients (HR = 1.777, 95% CI: 1.328-2.376). Compared with patients with low SII values, patients with high SII had lower PFS (HR = 1.658, 95% CI: 1.189-2.311). Subgroup analysis further verified the above results.

Conclusions

SII may be a noninvasive and powerful tool for predicting survival outcomes in CRC patients. However, more well-designed studies are needed to validate our findings.

Cancer-Associated Angiogenesis: The Endothelial Cell as a Checkpoint for Immunological Patrolling

Simple Summary

A clinical decision and study design investigating the level and extent of angiogenesis modulation aimed at vascular normalization without rendering tissues hypoxic is key and represents an unmet medical need. Specifically, determining the active concentration and optimal times of the administration of antiangiogenetic drugs is crucial to inhibit the growth of any microscopic residual tumor after surgical resection and in the pre-malignant and smolder neoplastic state. This review uncovers the pre-clinical translational insights crucial to overcome the caveats faced so far while employing anti-angiogenesis. This literature revision also explores how abnormalities in the tumor endothelium harm the crosstalk with an effective immune cell response, envisioning a novel combination with other anti-cancer drugs and immunomodulatory agents. These insights hold vast potential to both repress tumorigenesis and unleash an effective immune response.

Abstract

Cancer-associated neo vessels’ formation acts as a gatekeeper that orchestrates the entrance and egress of patrolling immune cells within the tumor milieu. This is achieved, in part, via the directed chemokines’ expression and cell adhesion molecules on the endothelial cell surface that attract and retain circulating leukocytes. The crosstalk between adaptive immune cells and the cancer endothelium is thus essential for tumor immune surveillance and the success of immune-based therapies that harness immune cells to kill tumor cells. This review will focus on the biology of the endothelium and will explore the vascular-specific molecular mediators that control the recruitment, retention, and trafficking of immune cells that are essential for effective antitumor immunity. The literature revision will also explore how abnormalities in the tumor endothelium impair crosstalk with adaptive immune cells and how targeting these abnormalities can improve the success of immune-based therapies for different malignancies, with a particular focus on the paradigmatic example represented by multiple myeloma. We also generated and provide two original bio-informatic analyses, in order to sketch the physiopathology underlying the endothelial–neoplastic interactions in an easier manner, feeding into a vicious cycle propagating disease progression and highlighting novel pathways that might be exploited therapeutically.

Bone metastases

Bone is the most frequent site for metastasis for many cancers, notably for tumours originating in the breast and the prostate. Tumour cells can escape from the primary tumour site and colonize the bone microenvironment. Within the bone, these disseminated tumour cells, as well as those arising in the context of multiple myeloma, may assume a state of dormancy, remaining quiescent for years before resuming proliferation and causing overt metastasis, which causes bone destruction via activation of osteoclast-mediated osteolysis. This structural damage can lead to considerable morbidity, including pain, fractures and impaired quality of life. Although treatment of bone metastases and myeloma bone disease is rarely curative, disease control is often possible for many years through the use of systemic anticancer treatments on a background of multidisciplinary supportive care. This care should include bone-targeted agents to inhibit tumour-associated osteolysis and prevent skeletal morbidity as well as use of appropriate local treatments such as radiation therapy, orthopaedic surgery and specialist palliative care to minimize the impact of metastatic bone disease on physical functioning. In this Primer, we provide an overview of the clinical features, the pathophysiology and the specific treatment approaches to prevent and treat bone metastases from solid tumours as well as myeloma bone disease.

Early Change in the Plasma Levels of Circulating Soluble Immune Checkpoint Proteins in Patients with Unresectable Hepatocellular Carcinoma Treated by Lenvatinib or Transcatheter Arterial Chemoembolization

Immune checkpoint inhibitors, combined with anti-angiogenic agents or locoregional treatments (e.g., transarterial chemoembolization (TACE)), are expected to become standard-of-care for unresectable hepatocellular carcinoma (HCC). We measured the plasma levels of 16 soluble checkpoint proteins using multiplexed fluorescent bead-based immunoassays in patients with HCC who underwent lenvatinib (n = 24) or TACE (n = 22) treatment. In lenvatinib-treated patients, plasma levels of sCD27 (soluble cluster of differentiation 27) decreased (p = 0.040) and levels of sCD40 (p = 0.014) and sTIM-3 (p < 0.001) were increased at Week 1, while levels of sCD27 (p < 0.001) were increased significantly at Weeks 2 through 4. At Week 1 of TACE, in addition to sCD27 (p = 0.028), sCD40 (p < 0.001), and sTIM-3 (soluble T-cell immunoglobulin and mucin domain-3) (p < 0.001), levels of sHVEM (soluble herpesvirus entry mediator) (p = 0.003), sTLR-2 (soluble Toll-like receptor 2) (p = 0.009), sCD80 (p = 0.036), sCTLA-4 (soluble cytotoxic T-lymphocyte antigen 4) (p = 0.005), sGITR (soluble glucocorticoid-induced tumor necrosis factor receptor) (p = 0.030), sGITRL (soluble glucocorticoid-induced TNFR-related ligand) (p = 0.090), and sPD-L1 (soluble programmed death-ligand 1) (p = 0.070) also increased. The fold-changes in soluble checkpoint receptors and their ligands, including sCTLA-4 with sCD80/sCD86 and sPD-1 (soluble programmed cell death domain-1) with sPD-L1 were positively correlated in both the lenvatinib and TACE treatment groups. Our results suggest that there are some limited differences in immunomodulatory effects between anti-angiogenic agents and TACE. Further studies from multicenters may help to identify an effective combination therapy.

New Insights into Diffuse Large B-Cell Lymphoma Pathobiology

Diffuse large B-cell lymphoma (DLBCL) is the most common non-Hodgkin lymphoma (NHL), accounting for about 40% of all cases of NHL. Analysis of the tumor microenvironment is an important aspect of the assessment of the progression of DLBCL. In this review article, we analyzed the role of different cellular components of the tumor microenvironment, including mast cells, macrophages, and lymphocytes, in the tumor progression of DLBCL. We examined several approaches to confront the available pieces of evidence, whereby three key points emerged. DLBCL is a disease of malignant B cells spreading and accumulating both at nodal and at extranodal sites. In patients with both nodal and extranodal lesions, the subsequent induction of a cancer-friendly environment appears pivotal. The DLBCL cell interaction with mature stromal cells and vessels confers tumor protection and inhibition of immune response while delivering nutrients and oxygen supply. Single cells may also reside and survive in protected niches in the nodal and extranodal sites as a source for residual disease and relapse. This review aims to molecularly and functionally recapitulate the DLBCL–milieu crosstalk, to relate niche and pathological angiogenic constitution and interaction factors to DLBCL progression.

The Clinicopathological Features and Genetic Alterations in Epstein-Barr Virus-Associated Gastric Cancer Patients after Curative Surgery

Background: Epstein–Barr virus (EBV)-associated gastric cancer (GC) is one of four major gastric cancer types and is traditionally considered to be related to lymphoepithelioma-like GC. Few studies have investigated the clinical significance of EBV infection in intestinal/solid type, diffuse (poorly cohesive) type, and lymphoepithelioma-like GC. Methods: A total of 460 GC patients receiving curative surgery were enrolled. The clinicopathological features, genetic alterations and prognoses were compared between patients with and without EBV infection. Results: EBV-positive GC patients (n = 43) had more tumors located in the upper and middle stomach, more common in lymphoepithelioma-like carcinoma, more lymphoid stroma, fewer Helicobacter pylori infections, and higher programmed death-ligand 1 (PD-L1) expression than EBV-negative GC patients. For intestinal/solid type GC, EBV-positive tumors were more likely to be located in the upper and middle stomach, have more lymphoid stroma, fewer Helicobacter pylori infections, higher PD-L1 expression, and more liver metastases than EBV-negative tumors. For diffuse (poorly cohesive) type GC, EBV-positive tumors were more likely to be located in the upper stomach, and have more lymphoid stroma than EBV-negative tumors. For lymphoepithelioma-like GC, EBV-positive tumors had more PI3K/AKT pathway mutations than EBV-negative tumors. Conclusions: Intestinal/solid type GC patients with EBV-positive tumors were associated with higher PD-L1 expression and more liver metastases, while lymphoepithelioma-like GC patients with EBV-positive tumors had more PI3K/AKT pathway mutations. Immunotherapy and targeted therapy may be beneficial for these groups of patients. Routine EBV survey is recommended in GC.

Immune Checkpoint Inhibitor-Related Myositis: From Biology to Bedside

Immune checkpoint inhibitor (ICI)-related inflammatory diseases, including polymyositis (PM) and dermatomyositis (DM), in patients suffering from neoplastic disorders represent a medical challenge. The treatment of these conditions has taken on new urgency due to the successful and broad development of cancer-directed immunological-based therapeutic strategies. While primary and secondary PM/DM phenotypes have been pathophysiologically characterized, a rational, stepwise approach to the treatment of patients with ICI-related disease is lacking. In the absence of high-quality evidence to guide clinical judgment, the available data must be critically assessed. In this literature review, we examine partially neglected immunological and clinical findings to obtain insights into the biological profiles of ICI-related PM/DM and potential treatment options. We show that differential diagnosis is essential to stratifying patients according to prognosis and therapeutic impact. Finally, we provide a comprehensive assessment of druggable targets and suggest a stepwise patient-oriented approach for the treatment of ICI-related PM/DM.

microRNAs in the Antitumor Immune Response and in Bone Metastasis of Breast Cancer: From Biological Mechanisms to Therapeutics

Breast cancer is the most common type of cancer in women, and the occurrence of metastasis drastically worsens the prognosis and reduces overall survival. Understanding the biological mechanisms that regulate the transformation of malignant cells, the consequent metastatic transformation, and the immune surveillance in the tumor progression would contribute to the development of more effective and targeted treatments. In this context, microRNAs (miRNAs) have proven to be key regulators of the tumor-immune cells crosstalk for the hijack of the immunosurveillance to promote tumor cells immune escape and cancer progression, as well as modulators of the metastasis formation process, ranging from the preparation of the metastatic site to the transformation into the migrating phenotype of tumor cells. In particular, their deregulated expression has been linked to the aberrant expression of oncogenes and tumor suppressor genes to promote tumorigenesis. This review aims at summarizing the role and functions of miRNAs involved in antitumor immune response and in the metastasis formation process in breast cancer. Additionally, miRNAs are promising targets for gene therapy as their modulation has the potential to support or inhibit specific mechanisms to negatively affect tumorigenesis. With this perspective, the most recent strategies developed for miRNA-based therapeutics are illustrated.