Prognostic significance and immune correlates of CD73 expression in renal cell carcinoma

Novel molecular mechanisms of immune evasion in hepatocellular carcinoma: NSUN2-mediated increase of SOAT2 RNA methylation

BACKGROUND

Hepatocellular carcinoma (HCC) is a deadly malignancy known for its ability to evade immune surveillance. NOP2/Sun RNA methyltransferase family member 2 (NSUN2), an RNA methyltransferase involved in carcinogenesis, has been associated with immune evasion and energy metabolism reprogramming. This study aimed to examine the molecular mechanisms underlying the involvement of NSUN2 in immune evasion and metabolic reprogramming of HCC.

METHODS

Single-cell transcriptomic sequencing was applied to examine cellular composition changes, particularly immune cell dynamics, in HCC and adjacent normal tissues. Bulk RNA-seq and proteomics identified key genes and proteins. Methylation sequencing and methylated RNA immunoprecipitation (MeRIP) were carried out to characterize the role of NSUN2 in 5-methylcytosine (m5C) modification of sterol O-acyltransferase 2 (SOAT2). Clinical samples from 30 HCC patients were analyzed using reverse transcription-quantitative polymerase chain reaction and Western blotting. Gene expression was manipulated using CRISPR/Cas9 and lentiviral vectors. In vitro co-culture models and metabolomics were used to study HCC cell-T cell interactions, energy metabolism, and immune evasion. Tumor growth in an orthotopic mouse model was monitored by bioluminescence imaging, with subsequent measurements of tumor weight, volume, and immunohistochemical staining.

RESULTS

Single-cell transcriptomic analysis identified a marked increase in malignant cells in HCC tissues. Cell communication analysis indicated that tumor cells might promote cancer progression by evading immune clearance. Multi-omics analyses identified NSUN2 as a key regulator in HCC development. MeRIP confirmed that NSUN2 facilitated the m5C modification of SOAT2. Analysis of human HCC tissue samples demonstrated pronounced upregulation of NSUN2 and SOAT2, along with elevated m5C levels in HCC tissues. In vitro experiments uncovered that NSUN2 augmented the reprogramming of energy metabolism and repressed the activity and cytotoxicity of CD8+ T cells, contributing to immune evasion. In vivo studies further substantiated the role of NSUN2 in fostering immune evasion and tumor formation of HCC by modulating the m5C modification of SOAT2.

CONCLUSIONS

The findings highlight the critical role of NSUN2 in driving HCC progression through the regulation of m5C modification on SOAT2. These findings present potential molecular markers for HCC diagnosis and therapeutic targets for its treatment.

Increased primary breast tumor expression of CD73 is associated with development of bone metastases and is a potential biomarker for adjuvant bisphosphonate use

PURPOSE

Increased CD73 expression has been associated with progression in various cancer types. Results of the AZURE and other trials suggest that, in postmenopausal breast cancer patients, adjuvant bisphosphonates inhibit bone relapses and prolong overall survival. Based on these findings, adjuvant bisphosphonates (typically zoledronic acid) are standard-of-care in postmenopausal patients with high-risk early breast cancer. However, biomarkers are needed for improved patient selection. The aim of this study was to investigate the association of primary tumor CD73 expression with later development of bone metastases.

METHODS

To determine whether CD73 levels correlated with tumor parameters (hormone receptor status, tumor stage and grade), patient outcomes (bone metastases and survival) or other patient characteristics (menopausal status, chemotherapy or statin use), we analyzed primary breast tumor CD73 expression immunohistochemically in tumor microarray samples from the AZURE (BIG01/04) trial.

RESULTS

In the AZURE control arm, high CD73 score are significantly prognostic for overall survival (p-value = 0.03, HR = 1.87, 95% CI = 1.06-3.29), disease-free survival (p-value = 0.06, HR = 1.66, 95% CI = 0.982-2.8) and time to first metastasis to bone (p-value = 0.04, HR = 2.23, 95% CI = 1.04-4.81), as compared with low CD73 scores. However, high CD73 score did not display an association with time to non-bone metastasis or first recurrence to a non-skeletal site. In the zoledronate arm, high CD73 score did not have association with patient outcomes, first metastasis to bone, nor with bone recurrence at any time (distant recurrence, including skeletal) or first non-skeletal recurrence. In multivariate testing, CD73 had no significant association with age, ER status, tumor stage, histological grade, menopausal status, chemotherapy or statin use in either arm.

CONCLUSIONS

High CD73 expression is associated with development of bone metastases. Zoledronate counteracts this effect. These results suggest that CD73 expression might serve as a biomarker for adjuvant zoledronic acid use.

CD73: a new immune checkpoint for leukemia treatment

Recent studies on the pathogenesis of leukemia have led to remarkable advances in disease treatment. Numerous studies have shown the potential and viability of immune responses against leukemia. In the classical pathway, this process is often initiated by the upstream activity of CD39, which hydrolyzes extracellular adenosine triphosphate (ATP) and adenosine diphosphate (ADP) to AMP. Subsequently, CD73 acts on AMP to generate adenosine, contributing to an immunosuppressive microenvironment. However, CD73 can also utilize substrates derived from other molecules through the non-canonical NAD+ pathway, specifically via the CD38/CD203a/CD73 axis, further enhancing adenosine production and facilitating immune escape. Targeting CD73 has shown potential in disrupting these immunosuppressive pathways, thereby enhancing anti-leukemic immune responses and improving patient outcomes. Inhibiting CD73 not only reduces the levels of immunosuppressive adenosine but also increases the efficacy of existing immunotherapies, such as PD-1/PD-L1 inhibitors, making it a versatile therapeutic target in leukemia treatment. This review discusses the potential of CD73 as a therapeutic target and emphasizes its unique position in the immune escape mechanism of leukemia. Moreover, this review provides an overview of the current research progress and future trends, emphasizing the clinical significance of targeting CD73 and other potential therapeutic strategies in leukemia.

Co-Delivery of aPD-L1 and CD73 Inhibitor Using Calcium Phosphate Nanoparticles for Enhanced Melanoma Immunotherapy with Reduced Toxicity

Melanoma, a malignant skin tumor, presents significant treatment challenges, particularly in unresectable and metastatic cases. While immune checkpoint inhibitors (ICIs) targeting PD-1/PD-L1 have brought new hope, their efficacy is limited by low response rates and significant immune-mediated adverse events (irAEs). Through multi-omics data analysis, it is discovered that the spatial co-localization of CD73 and PD-L1 in melanoma correlates with improved progression-free survival (PFS), suggesting a synergistic potential of their inhibitors. Building on these insights, a novel therapeutic strategy using calcium phosphate (CaP) nanoparticles is developed for the co-delivery of aPD-L1 and APCP, a CD73 inhibitor. These nanoparticles, constructed via a biomineralization method, exhibit high drug-loading capacity and pH-responsive drug release. Compared to free aPD-L1, the CaP-delivered aPD-L1 effectively avoids systemic side effects while significantly enhancing anti-tumor efficacy, surpassing even a 20-fold dose of free aPD-L1. Furthermore, the co-delivery of aPD-L1 and APCP via CaP nanoparticles demonstrates a synergistic anti-tumor effect, with substantial immune activation and prevention of tumor recurrence through immune memory effects. These findings suggest that the co-delivery of aPD-L1 and APCP using CaP nanoparticles is a promising approach for improving melanoma immunotherapy, achieving enhanced efficacy and reduced toxicity.

Integrated multiomics revealed adenosine signaling predict immunotherapy response and regulate tumor ecosystem of melanoma

Extracellular adenosine is extensively involved in regulating the tumor microenvironment. Given the disappointing results of adenosine-targeted therapy trials, personalized treatment might be necessary, tailored to the microenvironment status of individual patients. Here, we introduce the adenosine signaling score (ADO-score) model using non-negative matrix fraction identified patient subtypes using publicly available melanoma dataset, which aimed to profile adenosine signaling-related genes and construct a model to predict prognosis. We analyzed 580 malignant melanoma samples and demonstrated its robust value for prognosis. Further investigation in immune checkpoint inhibitor dataset suggests its potential as a stratified factor of immune checkpoint inhibitor efficacy. We validated the power of the ADO-score at the protein level immunofluorescence in a melanoma cohort from Xiangya Hospital. More importantly, single-cell and spatial transcriptomic data highlighted the cell-specific expression patterns of adenosine signaling-related genes and the existence of adenosine signaling-mediated crosstalk between tumor cells and immune cells in melanoma. Our study reveals a robust connection between adenosine signaling and clinical benefits in melanoma patients and proposes a universally applicable adenosine signaling model, the ADO-score, in gene expression profiles and histological sections. This model enables us to more precisely and conveniently select patients who are likely to benefit from immunotherapy.

Immune Features of Tumor Microenvironment: A Genetic Spotlight

A tumor represents a highly intricate tissue entity, characterized by an exceptionally complex microenvironment that starkly contrasts with the typical physiological surroundings of healthy tissues. Within this tumor microenvironment (TME), every component and factor assume paramount importance in the progression of malignancy and exerts a pivotal influence on a patient's clinical outcome. One of the remarkable aspects of the TME is its remarkable heterogeneity, not only across different types of cancers but even within the same histological category of tumors. In-depth research has illuminated the intricate interplay between specific immune cells and molecules and the dynamic characteristics of the TME. Recent investigations have yielded compelling evidence that several mutations harbored by tumor cells possess the capacity to instigate substantial alterations in the TME. These mutations, often acting as drivers of tumorigenesis, can orchestrate a cascade of events that remodel the TME, thereby influencing crucial aspects of cancer behavior, including its invasiveness, immune evasion, and response to therapies. It is within this nuanced context that the present study endeavors to provide a concise yet comprehensive summary of how specific mutations, within the genetic landscape of cancer cells, can instigate profound changes in TME features. By elucidating the intricate relationship between genetic mutations and the TME, this research aims to contribute to a deeper understanding of cancer biology. Ultimately, the knowledge gained from this study holds the potential to inform the development of more targeted and effective treatments, thereby offering new hope to patients grappling with the complexities of cancer.

Effects of abnormal expression of CD73 on malignant phenotype of nasopharyngeal carcinoma

Cluster of differentiation (CD) 73, encoded by the NT5E gene, plays important enzymatic and non-enzymatic roles in cells. There is growing evidence show that CD73 is a key regulator in the development of tumor. Nasopharyngeal carcinoma (NPC) is one of the most common cancers in east and southeast Asia. It is urgent to know more about the mechanism of NPC development and find diagnostic markers for the patients. In this research, we carried out western blot, immunohistochemistry and qRT-PCR to investigate the expression level of CD73 and found that NPC tissues had higher level of CD73 than normal tissues. We also detected the relationship between its expression level with the clinicopathological features and prognosis of NPC patients. The results showed that CD73 expression was related to the clinical stages, lymph node metastasis and survival state of NPC patients. More importantly, patients with higher expression of CD73 had poorer prognosis. Then, CD73 was knocked down in NPC cells (CNE2 and CNE1), and its effects on cell proliferation and migration were investigated by CCK8, colony formation, Transwell and wound-healing assays. We found that knocking down the expression of CD73 in NPC cells could inhibit cells malignant phenotype. Collectively, CD73 plays important roles in NPC malignant behavior and might act as a novel target for the diagnosis and treatment of NPC.

The Immune Regulatory Role of Adenosine in the Tumor Microenvironment

Adenosine, an immunosuppressive metabolite, is produced by adenosine triphosphate (ATP) released from dying or stressed cells and is found at high levels in the tumor microenvironment of most solid tumors. It mediates pro-tumor activities by inducing tumor cell proliferation, migration or invasion, tumor tissue angiogenesis, and chemoresistance. In addition, adenosine plays an important role in regulating anti-tumor immune responses and facilitating tumor immune escape. Adenosine receptors are broadly expressed by tumor-infiltrated immune cells, including suppressive tumor-associated macrophages and CD4+ regulatory T cells, as well as effector CD4+ T cells and CD8+ cytotoxic T lymphocytes. Therefore, adenosine is indispensable in down-regulating anti-tumor immune responses in the tumor microenvironment and contributes to tumor progression. This review describes the current progress on the role of adenosine/adenosine receptor pathway in regulating the tumor-infiltrating immune cells that contribute to tumor immune evasion and aims to provide insights into adenosine-targeted tumor immunotherapy.

Functionalized chitosan for cancer nano drug delivery

Chitosan is a biotechnological derivative of chitin receiving a widespread pharmaceutical and biomedical applications. It can be used to encapsulate and deliver cancer therapeutics with inherent pH-dependent solubility to confer drug targeting at tumour microenvironment and anti-cancer activity synergizing cancer cytotoxic drug actions. To further reduce the off-target and by-stander adverse effects of drugs, a high targeted drug delivery efficiency at the lowest possible drug doses is clinically required. The chitosan has been functionalized with covalent conjugates or complexes and processed into nanoparticles to encapsulate and control drug release, to avoid premature drug clearance, to deliver drugs passively and actively to cancer site at tissue, cell or subcellular levels, and to promote cancer cell uptake of nanoparticles through membrane permeabilization at higher specificity and scale. Nanomedicine developed using functionalized chitosan translates to significant preclinical improvements. Future challenges related to nanotoxicity, manufacturability, selection precision of conjugates and complexes as a function of cancer omics and their biological responses from administration site to cancer target need critical assessments.

Prognostic effect of CD73 in pancreatic ductal adenocarcinoma for disease-free survival after radical surgery

PURPOSE

Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease with a high potency of metastasis or recurrence after radical resection. Effective predictors for metastasis and recurrence postoperatively were dominant for the development of systemic adjuvant treatment regimens. The ATP hydrolase correlated gene CD73 was described as a promoter in tumor growth and immune escape of PDAC. However, there lacked research focused on the role of CD73 in PDAC metastasis. This study aimed to investigate the expression of CD73 in PDAC patients with different outcomes as well as the prognostic effect of CD73 for disease-free survival (DFS).

METHODS

The expression level of CD73 in cancerous samples from 301 PDAC patients was evaluated by immunohistochemistry (IHC) and translated into a histochemistry score (H-score) by the HALO analysis system. Then, the CD73 H-score was involved in multivariate Cox regression along with other clinicopathological characteristics to find independent prognostic factors for DFS. Finally, a nomogram was constructed based on those independent prognostic factors for DFS prediction.

RESULTS

Higher CD73 expression was found in PDAC patients with tumor metastasis postoperatively. Meanwhile, higher CD73 expressions were also investigated in PDAC patients diagnosed with advanced N stage and T stage. Furthermore, CD73 H-score along with tumor margin status, CA19-9, 8th N stage, and adjuvant chemotherapy was indicated as independent prognostic factors for DFS in PDAC patients. The nomogram based on these factors predicted DFS in a good manner.

CONCLUSION

CD73 was associated with PDAC metastasis and served as an effective prognostic factor for DFS in PDAC patients after radical surgery.

CD73 regulates zoledronate-induced lymphocyte infiltration in triple-negative breast cancer tumors and lung metastases

Introduction

Bisphosphonates (BPs) are bone-protecting osteoclast inhibitors, typically used in the treatment of osteoporosis and skeletal complications of malignancies. When given in the adjuvant setting, these drugs may also prevent relapses and prolong overall survival in early breast cancer (EBC), specifically among postmenopausal patients. Because of these findings, adjuvant nitrogen-containing BPs (N-BPs), such as zoledronate (ZOL), are now the standard of care for high-risk EBC patients, but there are no benefit-associated biomarkers, and the efficacy remains low. BPs have been demonstrated to possess anti-tumor activities, but the mechanisms by which they provide the beneficial effects in EBC are not known.

Methods

We used stably transfected 4T1 breast cancer cells together with suppression of CD73 (sh-CD73) or control cells (sh-NT). We compared ZOL effects on tumor growth and infiltrating lymphocytes (TILs) into tumors and lung metastases using two mouse models. B cell depletion was performed using anti-CD20 antibody.

Results

Sh-CD73 4T1 cells were significantly more sensitive to the growth inhibitory effects of n-BPs in vitro. However, while ZOL-induced growth inhibition was similar between the tumor groups in vivo, ZOL enhanced B and T lymphocyte infiltration into the orthotopic tumors with down-regulated CD73. A similar trend was detected in lung metastases. ZOL-induced tumor growth inhibition was found to be augmented with B cell depletion in sh-NT tumors, but not in sh-CD73 tumors. As an internal control, ZOL effects on bone were similar in mice bearing both tumor groups.

Discussion

Taken together, these results indicate that ZOL modifies TILs in breast cancer, both in primary tumors and metastases. Our results further demonstrate that B cells may counteract the growth inhibitory effects of ZOL. However, all ZOL-induced TIL effects may be influenced by immunomodulatory characteristics of the tumor.

Immunotherapy and Immune Infiltration in Patients with Clear Cell Renal Cell Carcinoma: A Comprehensive Analysis

On a global scale, renal cell carcinoma (RCC) is the second most common form of cancer and the 10th leading cause of cancer-related deaths. There are about 70% of cases of RCC that are clear cell renal cell carcinomas (ccRCCs). This study explores possible targets for immune therapy in patients with RCC. In the recent years, immunotherapy has been applied to RCC patients. In order to identify genes that are closely associated with immune cells, a weighted gene coexpression network analysis (WGCNA) was conducted. A close association was found between genes involved in MEred and M0 macrophages, M1 macrophages, and M2 macrophages. A prognostic prediction model is subsequently developed by incorporating the OS and the expression level of key genes from the RCC cohort into a univariate COX regression analysis, a multivariate COX regression analysis, and a combined COX regression analysis. We finally discovered that 6 genes are closely associated with the prognosis of RCC patients, including SLC16A12, SLC2A9, IGF2BP2, EMX2, ANK3, and METTL7A. The survival analysis proved the prognostic prediction value of the model. The 1-year, 3-year, and 5-year AUC of ROC curves are 0.759, 0.723, and 0.733, respectively. For clinical ROC curves, the AUC score for risk score, stage, grade, and T stage is 0.759, 0.824, 0722, and 0.736, respectively. The nomogram was constructed for better prognosis prediction of RCC patients. In addition, GSVA and GO enrichment analysis was performed to explore the potential pathways that are closely associated with genes involved in the prognostic prediction model. Accordingly, our study demonstrates that immune cells play a crucial role in RCC infiltration. The development of a prognostic prediction model is a potential new prognostic biomarker and potential immunotherapy target for tumors.

CD39/CD73/A2AR pathway and cancer immunotherapy

Cancer development is closely associated with immunosuppressive tumor microenvironment (TME) that attenuates antitumor immune responses and promotes tumor cell immunologic escape. The sequential conversion of extracellular ATP into adenosine by two important cell-surface ectonucleosidases CD39 and CD73 play critical roles in reshaping an immunosuppressive TME. The accumulated extracellular adenosine mediates its regulatory functions by binding to one of four adenosine receptors (A1R, A2AR, A2BR and A3R). The A2AR elicits its profound immunosuppressive function via regulating cAMP signaling. The increasing evidence suggests that CD39, CD73 and A2AR could be used as novel therapeutic targets for manipulating the antitumor immunity. In recent years, monoclonal antibodies or small molecule inhibitors targeting the CD39/CD73/A2AR pathway have been investigated in clinical trials as single agents or in combination with anti-PD-1/PD-L1 therapies. In this review, we provide an updated summary about the pathophysiological function of the adenosinergic pathway in cancer development, metastasis and drug resistance. The targeting of one or more components of the adenosinergic pathway for cancer therapy and circumvention of immunotherapy resistance are also discussed. Emerging biomarkers that may be used to guide the selection of CD39/CD73/A2AR-targeting treatment strategies for individual cancer patients is also deliberated.

High expression of CD73 contributes to poor prognosis of clear-cell renal cell carcinoma by promoting cell proliferation and migration

BACKGROUND

Accumulating data have shown that high expression of CD73 is associated with poor prognosis in various cancers, however the role and significance of CD73 in clear-cell renal cell carcinoma (ccRCC) still remain unclear. The present study aims to evaluate the prognostic significance of CD73 in ccRCC and explore the potential function in vitro and in vivo.

METHODS

Firstly, the expression of CD73 in ccRCC was detected using clinical tissues and verified using TCGA and GEO data. Immunohistochemistry and Kaplan-Meier test were performed for survival analysis. Furthermore, knockdown or overexpression of CD73 was conducted by lentivirus transfection in ccRCC cells. MTT assay, colony formation assay, wound healing assay, transwell assay and xenograft assay were performed in vitro or in vivo.

RESULTS

Our results showed that CD73 was highly expressed in ccRCC, and high expression of CD73 was negatively correlated with prognosis. In addition, CD73 promoted cell proliferation and migration in vitro and in vivo. Our data also showed that CD73 played both enzymatic and non-enzymatic functions in the regulation of cell proliferation and migration in ccRCC.

CONCLUSIONS

These findings suggested that CD73 might promote the growth of ccRCC and contribute to poor prognosis. Taken together, CD73 may be a potential therapeutic target in ccRCC.

Adenosine signaling: Optimal target for gastric cancer immunotherapy

Gastric cancer (GC) is one of the most common malignancy and leading cause of cancer-related deaths worldwide. Due to asymptomatic or only nonspecific early symptoms, GC patients are usually in the advanced stage at first diagnosis and miss the best opportunity of treatment. Immunotherapies, especially immune checkpoint inhibitors (ICIs), have dramatically changed the landscape of available treatment options for advanced-stage cancer patients. However, with regards to existing ICIs, the clinical benefit of monotherapy for advanced gastric cancer (AGC) is quite limited. Therefore, it is urgent to explore an optimal target for the treatment of GC. In this review, we summarize the expression profiles and prognostic value of 20 common immune checkpoint-related genes in GC from Gene Expression Profiling Interactive Analysis (GEPIA) database, and then find that the adenosinergic pathway plays an indispensable role in the occurrence and development of GC. Moreover, we discuss the pathophysiological function of adenosinergic pathway in cancers. The accumulation of extracellular adenosine inhibits the normal function of immune effector cells and facilitate the effect of immunosuppressive cells to foster GC cells proliferation and migration. Finally, we provide insights into potential clinical application of adenosinergic-targeting therapies for GC patients.

Redistribution of CD8+ T cell subsets in metastatic renal cell carcinoma patients treated with anti-PD-1 therapy

Renal‐cell carcinoma (RCC) is responsible for the majority of tumors arising from the kidney parenchyma. Although a progressive improvement in median overall survival has been observed after the introduction of anti‐PD‐1 therapy, many patients do not benefit from this treatment. Therefore, we have investigated T cell dynamics to find immune modification induced by anti‐PD‐1 therapy. Here, we show that, after therapy, RCC patients (5 responders and 14 nonresponders) are characterized by a redistribution of different subsets across the memory T cell compartment.

Targeting nucleotide metabolism: a promising approach to enhance cancer immunotherapy

Targeting nucleotide metabolism can not only inhibit tumor initiation and progression but also exert serious side effects. With in-depth studies of nucleotide metabolism, our understanding of nucleotide metabolism in tumors has revealed their non-proliferative effects on immune escape, indicating the potential effectiveness of nucleotide antimetabolites for enhancing immunotherapy. A growing body of evidence now supports the concept that targeting nucleotide metabolism can increase the antitumor immune response by (1) activating host immune systems via maintaining the concentrations of several important metabolites, such as adenosine and ATP, (2) promoting immunogenicity caused by increased mutability and genomic instability by disrupting the purine and pyrimidine pool, and (3) releasing nucleoside analogs via microbes to regulate immunity. Therapeutic approaches targeting nucleotide metabolism combined with immunotherapy have achieved exciting success in preclinical animal models. Here, we review how dysregulated nucleotide metabolism can promote tumor growth and interact with the host immune system, and we provide future insights into targeting nucleotide metabolism for immunotherapeutic treatment of various malignancies.

Functional antigen processing and presentation mechanism as a prerequisite factor of response to treatment with dendritic cell vaccines and anti-PD-1 in preclinical murine LLC1 and GL261 tumor models

Low efficacy of cancer immunotherapy encourages the search for possible resistance mechanisms and biomarkers that would predict the outcome of immunotherapy in oncology patients. Most cancer immunotherapies act on T lymphocytes, which can specifically recognize and kill tumor cells. However, for immunotherapy-activated T lymphocytes to be able to perform these functions, proper tumor Ag processing and surface presentation by MHC-I molecule is important. Knowing the significance of Ag processing and presentation mechanism (APM) in anti-tumor immune response, we sought to evaluate how the functionality of APM affects tumor immune microenvironment and response to dendritic cell vaccines (DCV) and anti-PD-1. By comparing murine Lewis lung carcinoma LLC1 and glioma GL261 models a decreased expression of APM-related genes, such as Psmb8, Psmb9, Psmb10, Tap1, Tap2, Erap1, B2m, and low expression of surface MHC-I molecule were found in LLC1 cells. Changes in APM-related gene expression affected the ability of T lymphocytes to recognize and kill LLC1 cells, resulting in the absence of cytotoxic immune response and resistance to DCV and anti-PD-1. An emerging cytotoxic immune reaction and sensitivity to DCV and anti-PD-1 were observed in GL261 tumors where APM remained functional. This study demonstrates that one of the possible mechanisms of tumor resistance to immunotherapy is a dysfunctional APM and reveals a predictive potential of APM-related gene set expression for the personalization of dendritic cell vaccine and anti-PD-1 therapies in murine pre-treated tumors.

NT5E gene and CD38 protein as potential prognostic biomarkers for childhood B-acute lymphoblastic leukemia

The risk stratification of B-acute lymphoblastic leukemia (B-ALL) is based on clinical and biological factors. However, B-ALL has significant biological and clinical heterogeneity and 50% of B-ALL patients do not have defined prognostic markers. In this sense, the identification of new prognostic biomarkers is necessary. Considering different cohorts of childhood B-ALL patients, gene (DPP4/CD38/ENTPD1/NT5E) and protein (CD38/CD39/CD73) expressions of ectonucleotidases were analyzed in silico and ex vivo and the association with prognosis was established. In univariate analyses, expression of NT5E was significantly associated with worse progression-free survival (PFS) in bone marrow (BM) samples. In multivariate analyses, Kaplan-Meier analysis, and log-rank test, higher NT5E expression predicted unfavorable PFS in BM samples. Considering minimal residual disease (MRD), higher levels of cellularity were associated with the high NT5E expression at day 8 of induction therapy. In addition, we observed that white blood cells (WBC) of childhood B-ALL patients had more CD38 compared to the same cell population of healthy donors (HD). In fact, MRD > 0.1% patients had higher CD38 protein expression on WBC in comparison to HD. Noteworthy, we observed higher CD38 expression on WBC than blasts in MRD > 0.1% patients. We suggest that NT5E gene and CD38 protein expression, of the ectonucleotidases family, could provide interesting prognostic biomarkers for childhood B-ALL.

Resveratrol enhances A1 and hinders A2A adenosine receptors signaling in both HeLa and SH-SY5Y cells: Potential mechanism of its antitumoral action

Despite great efforts, effective treatment against cancer has not yet been found. However, natural compounds such as the polyphenol resveratrol have emerged as promising preventive agent in cancer therapy. The mode of action of resveratrol is still poorly understood, but it can modulate many signaling pathways related to the initiation and progression of cancer. Adenosinergic signaling may be involved in the antitumoral action of resveratrol since resveratrol binds to the orthosteric binding site of adenosine A_2A receptors and acts as a non-selective agonist for adenosine receptors. In the present study, we measured the impact of resveratrol treatment on different adenosinergic pathway components (i.e. adenosine receptors levels, 5'-nucleotidase, adenosine deaminase, and adenylyl cyclase activities, protein kinase A levels, intracellular adenosine and other related metabolites levels) and cell viability and proliferation in HeLa and SH-SY5Y cell lines. Results revealed changes leading to turning off cAMP signaling such as decreased levels of A_2A receptors and reduced adenylyl cyclase activation, increased levels of A₁ receptors and increased adenylyl cyclase inhibition, and lower levels of PKA. All these changes could contribute to the antitumoral action of resveratrol. Interestingly, these effects were almost identical in HeLa and SH-SY5Y cells suggesting that resveratrol enhances A₁ and hinders A_2A adenosine receptors signaling as part of a potential mechanism of antitumoral action.

Gene signatures with therapeutic value: emerging perspective for personalized immunotherapy in renal cancer

Renal cancer is one of the deadliest urogenital diseases. In recent years, the advent of immunotherapy has led to significant improvement in the management of patients with renal cancer. Although cancer immunotherapy and its combinations had benefited numerous patients, several challenges need to be addressed. Apart from the high costs of treatment, the lack of predictive biomarkers and toxic side-effects have impeded its wider applicability. To address these issues, new biomarkers are required to predict responsiveness and design personalized treatment strategies. Recent advances in the field of single-cell sequencing and multi-dimensional spatial transcriptomics have identified clinically relevant subtypes of renal cancer. Furthermore, there is emerging potential for gene signatures based on immune cells, non-coding RNAs, and pathways such as metabolism and RNA modification. In this review article, we have discussed recent progress in the identification of gene signatures with predictive and prognostic potential in renal cancer.

ATP and cancer immunosurveillance

While intracellular adenosine triphosphate (ATP) occupies a key position in the bioenergetic metabolism of all the cellular compartments that form the tumor microenvironment (TME), extracellular ATP operates as a potent signal transducer. The net effects of purinergic signaling on the biology of the TME depend not only on the specific receptors and cell types involved, but also on the activation status of cis- and trans-regulatory circuitries. As an additional layer of complexity, extracellular ATP is rapidly catabolized by ectonucleotidases, culminating in the accumulation of metabolites that mediate distinct biological effects. Here, we discuss the molecular and cellular mechanisms through which ATP and its degradation products influence cancer immunosurveillance, with a focus on therapeutically targetable circuitries.

Small-molecule CD73 inhibitors for the immunotherapy of cancer: a patent and literature review (2017-present)

INTRODUCTION

Hydrolysis of AMP to adenosine and inorganic phosphate is catalyzed by 5´-ectonucleotidase, e5NT, alias CD73, a metalloenzyme incorporating two zinc ions at its active site. e5NT is involved in crucial physiological and pathological processes, such as immune ho meostasis, inflammation, and tumor progression. CD73 inhibitors belonging to the monoclonal antibodies (MAbs) and small molecules started to be considered as candidates for the immunotherapy of tumors.

AREAS COVERED

We review the drug design landscape in the scientific and patent literature on CD73 inhibitors from 2017 to the present. Small-molecule inhibitors were mostly discussed, although the MAbs are also considered.

EXPERT OPINION

Considerable advances have been reported in the design of nucleotide/nucleoside-based CD73 inhibitors, after the X-ray crystal structure of the enzyme in complex with the non-hydrolyzable ADP analog, adenosine (α,β)-methylene diphosphate (AMPCP), was reported. A large number of highly effective such inhibitors are now available, through modifications of the nucleobase, sugar and zinc-binding groups of the lead. Few classes of non-nucleotide inhibitors were also reported, including flavones, anthraquinone ssulfonates, and primary sulfonamides. A highly potent ssmall-molecule CD73 inhibitor, AB680, is presently in the early phase of clinical trials as immunotherapeutic agents against various types of cancer.