Purinergic signaling and tumor microenvironment in cervical Cancer

Integrated immunological analysis of single-cell and bulky tissue transcriptomes reveals the role of interactions between M0 macrophages and naïve CD4+ T cells in the immunosuppressive microenvironment of cervical cancer

In recent decades, the incidence and mortality of cervical cancer have declined in developed countries due to the implementation of screening and vaccination programs. However, cervical cancer remains one of the major culprits of cancer-related deaths in young women. Current studies have found that immune cell-related intercellular communication in the tumor microenvironment has a large impact on the construction of the immunosuppressive microenvironment. In this study, we performed a comprehensive immune analysis on bulk RNA-seq and scRNA-seq data obtained from cervical cancer and revealed that two highly plastic cell populations, M0 macrophages and naïve CD4+ T cells, were significantly correlated with prognosis and clinical phenotypes. Notably, signaling between M0 macrophages and naïve CD4+ T cells as well as intracellular transcription factor activity were significantly altered in the tumor state. Furthermore, we identified overlapping genes between the transcription factor target genes of M0 macrophages or naïve CD4+ T cells and the differentially expressed genes in each type of cell, and these overlapping genes were subsequently subjected to an analysis using the LASSO regression model. Finally, we generated a score index that was significantly associated with the clinical prognosis of cervical cancer. In conclusion, interventions to improve the communication between M0 macrophages and naïve CD4+ T cells may help to improve the immunosuppressive microenvironment of cervical cancer and prevent immune evasion. The relevant molecular mechanisms need to be further validated by experimental and cohort studies.

P2X1 and P2X7 Receptor Overexpression Is a Negative Predictor of Survival in Muscle-Invasive Bladder Cancer

Bladder cancer is amongst the most common causes of cancer death worldwide. Muscle-invasive bladder cancer (MIBC) bears a particularly poor prognosis. Overexpression of purinergic P2X receptors (P2XRs) has been associated with worse outcome in several malignant tumors. Here, we investigated the role of P2XRs in bladder cancer cell proliferation in vitro and the prognostic value of P2XR expression in MIBC patients. Cell culture experiments with T24, RT4, and non-transformed TRT-HU-1 cells revealed a link between high ATP concentrations in the cell culture supernatants of bladder cell lines and a higher grade of malignancy. Furthermore, proliferation of highly malignant T24 bladder cancer cells depended on autocrine signaling through P2X receptors. P2X1R, P2X4R, and P2X7R expression was immunohistochemically analyzed in tumor specimens from 173 patients with MIBC. High P2X1R expression was associated with pathological parameters of disease progression and reduced survival time. High combined expression of P2X1R and P2X7R increased the risk of distant metastasis and was an independent negative predictor of overall and tumor-specific survival in multivariate analyses. Our results suggest that P2X1R/P2X7R expression scores are powerful negative prognostic markers in MIBC patients and that P2XR-mediated pathways are potential targets for novel therapeutic strategies in bladder cancer.

P2X7 receptor involved in antitumor activity of atractylenolide I in human cervical cancer cells

Atractylenolide I (Atr-I) was found to sensitize a variety of human cancer cells in previous studies. Purinergic P2X7R plays important role in different cancers. However, whether Atr-I could generate antitumor activity in human cervical cancer cells and P2X7R get involved in this effect remain unclear. In this study, Hela (HPV 18 +) and SiHa (HPV 16 +) cells were treated with different doses of Atr-I. The results indicated that agonist and antagonist of P2X7 receptors, BzATP and JNJ-47965567 (JNJ), could suppress the proliferation of Hela and SiHa cells. Atr-I demonstrated a considerable antitumor effect in both human cervical cancer cells in vitro. Atr-I combined with P2X7R agonist, BzATP, restored Atr-I-induced growth inhibition in Hela cells but not in SiHa cells. However, the combinatorial treatment of P2X7R antagonist JNJ and Atr-I has an additive effect on cell growth inhibition in SiHa cells rather than in Hela cells. It implied that P2X7R would get involved in the anti-human cervical cancer cells effect of Atr-I.

The P2 purinoceptors in prostate cancer

P2 purinoceptors are composed of ligand-gated ion channel type (P2X receptor) and G protein-coupled metabolite type (P2Y receptor). Both these receptors have played important roles in the prostate cancer microenvironment in recent years. P2X and P2Y receptors can contribute to prostate cancer's growth and invasiveness. However, the comprehensive mechanisms have yet to be identified. By summarizing the relevant studies, we believe that P2X and P2Y receptors play a dual role in cancer cell growth depending on the prostate cancer microenvironment and different downstream signalling pathways. We also summarized how different signalling pathways contribute to tumor invasiveness and metastasis through P2X and P2Y receptors, focusing on understanding the specific mechanisms led by P2X4, P2X7, and P2Y2. Statins may reduce and prevent tumor progression through P2X7 so that P2X purinergic receptors may have clinical implications in the management of prostate cancer. Furthermore, P2X7 receptors can aid in the early detection of prostate cancer. We hope that this review will provide new insights for future mechanistic and clinical investigations into the role of P2 purinergic receptors in prostate cancer.

Research Progress in the Relationship Between P2X7R and Cervical Cancer

Cervical cancer is one of the most common and serious tumors in women. Finding new biomarkers and therapeutic targets plays an important role in the diagnosis, prognosis, and treatment of cervical cancer. Purinergic ligand-gated ion channel 7 receptor (P2X7R) is a purine ligand cation channel, activated by adenosine triphosphate (ATP). Studies have shown that P2X7R plays an important role in a variety of diseases and cancers. More and more studies have shown that P2X7R is also closely related to cervical cancer; therefore, the role of P2X7R in the development of cervical cancer deserves further discussion. The expression level of P2X7R in uterine epithelial cancer tissues was lower than that of the corresponding normal tissues. P2X7R plays an important role in the apoptotic process of cervical cancer through various mechanisms of action, and both antagonists and agonists of P2X7R can inhibit the proliferation of cervical cancer cells, while P2X7R is involved in the antitumor effect of Atr-I on cervical cancer cells. This review evaluates the current role of P2X7R in cervical cancer in order to develop more specific therapies for cervical cancer. In conclusion, P2X7R may become a biomarker for cervical cancer screening, and even a new target for clinical treatment of cervical cancer.

Dissecting the Single-Cell Transcriptome Network of Immune Environment Underlying Cervical Premalignant Lesion, Cervical Cancer and Metastatic Lymph Nodes

Cervical cancer (CC) is one of the most common malignancy in women worldwide. It is characterized by a natural continuous phenomenon, that is, it is in the initial stage of HPV infection, progresses to intraepithelial neoplasia, and then develops into invasion and metastasis. Determining the complexity of tumor microenvironment (TME) can deepen our understanding of lesion progression and provide novel therapeutic strategies for CC. We performed the single-cell RNA sequencing on the normal cervix, intraepithelial neoplasia, primary tumor and metastatic lymph node tissues to describe the composition, lineage, and functional status of immune cells and mesenchymal cells at different stages of CC progression. A total of 59913 single cells were obtained and divided into 9 cellular clusters, including immune cells (T/NK cells, macrophages, B cells, plasma cells, mast cells and neutrophils) and mesenchymal cells (endothelial cells, smooth muscle cells and fibroblasts). Our results showed that there were distinct cell subpopulations in different stages of CC. High-stage intraepithelial neoplasia (HSIL) tissue exhibited a low, recently activated TME, and it was characterized by high infiltration of tissue-resident CD8 T cell, effector NK cells, Treg, DC1, pDC, and M1-like macrophages. Tumor tissue displayed high enrichment of exhausted CD8 T cells, resident NK cells and M2-like macrophages, suggesting immunosuppressive TME. Metastatic lymph node consisted of naive T cell, central memory T cell, circling NK cells, cytotoxic CD8+ T cells and effector memory CD8 T cells, suggesting an early activated phase of immune response. This study is the first to delineate the transcriptome profile of immune cells during CC progression using single-cell RNA sequencing. Our results indicated that HSIL exhibited a low, recently activated TME, tumor displayed immunosuppressive statue, and metastatic lymph node showed early activated phase of immune response. Our study enhanced the understanding of dynamic change of TME during CC progression and has implications for the development of novel treatments to inhibit the initiation and progression of CC.

Deregulation of purinergic ectoenzyme activity in head and neck cancer promotes immunosuppression

BACKGROUND

Head and neck cancer (HNC) comprises a spectrum of neoplasms that affect the upper aerodigestive tract and are the sixth most common cancers worldwide. Individuals with HNC exhibit various symptoms and metabolic changes, including immune alterations and alterations of the purinergic pathway, which may signal worse outcomes. Therefore, the purpose of this research was to measure the activity of purinergic ectoenzymes and interleukins in patients with HNC, oral cavity cancer, and larynx cancer.

METHODS AND RESULTS

We recruited 32 patients and 33 healthy control subjects and performed the laboratory analyses. We identified dysregulation in the purinergic signaling pathway characterized by an increase in adenosine triphosphate (ATP) and adenosine monophosphate (AMP) hydrolysis and a decrease in the deamination of adenosine to inosine in these cancers (p < 0.05). These alterations were likely caused by increased activity of the ectoenzymes E-NTPDase and ecto-5'-nucleotidase and reduced adenosine deaminase activity. This dysregulation was associated with immune alterations, increased levels of IL-10, and decreased myeloperoxidase activity (p < 0.05), suggesting immunosuppression in these patients and suggesting possible accumulation of adenosine in the extracellular environment.

CONCLUSIONS

Adenosine is a potent immunosuppressive molecule associated with tumor progression and immune evasion. Our findings suggest a relationship between extracellular purines and the development and progression of the tumor microenvironment and poor outcomes. These findings increase the understanding of biological mechanisms related to HNC and demonstrate that these components are potential diagnostic markers and therapeutic targets for future management strategies and improvement in the quality of life.

Potential roles of serum ATPase and AMPase in predicting diagnosis of colorectal cancer patients

Colorectal cancer (CRC) is a common gastrointestinal cancer with high incidence and mortality rates. CRC may be associated with regulation of circulating nucleotides. This study aimed to evaluate the serum levels of nucleotide-metabolizing enzymes (ATPase and AMPase) in patients with CRC and to explore the clinical diagnostic value of these enzymes. The gene set variation analysis (GSVA) score of the ATP-adenosine signature was calculated using tumor samples from The Cancer Genome Atlas (TCGA). ATP-adenosine signaling plays a central role in CRC progression. A total of 135 subjects, including 87 patients with CRC and 48 healthy controls, were included. The serum levels of ATPase and AMPase in the CRC group were significantly higher than those in the control group (P < 0.05). Furthermore, ATP and AMP hydrolysis levels significantly increased in the advanced CRC group (P < 0.05). ATP and AMP hydrolysis was decreased by the ENTPDase inhibitors (POM-1 and ARL67156) and CD73 inhibitor (APCP). The sensitivities of ATPase and AMPase were 95.4% and 75.9%, respectively, which were higher than those of CEA (67.8%) and CA19-9 (72.4%). The specificities of ATPase and AMPase were 69.9% and 73.9%, respectively, which were higher than that of CA19-9 (47.8%). The combination of CEA, ATPase, and AMPase demonstrated high sensitivity (92.0%) and specificity (87.0%). Collectively, ATPase and AMPase activities are upregulated in CRC with considerable diagnostic significance. The combination of CEA, ATPase, and AMPase may provide a novel approach for CRC screening.

Inflammatory profile in cervical cancer: influence of purinergic signaling and possible therapeutic targets

INTRODUCTION AND OBJECTIVE

Cervical cancer is the fourth most prevalent type of cancer in the world. The tumor microenvironment of this disease is associated with the production of several cytokines, pro and anti-inflammatory, and with the purinergic signaling system so that changes in these components are observed throughout the pathological process. The aim of this review is to understand the pathophysiology of cervical cancer based on immunological processes and purinergic signaling pathways, in addition to suggesting possibilities of therapeutic targets.

MATERIALS AND METHODS

To make up this review, studies covering topics of cervical cancer, inflammation and purinergic system were selected from the Pubmed.

RESULTS

The main pro-inflammatory cytokines involved are IL-17, IL-1β, IL-6, and IL-18, and among the anti-inflammatory ones, IL-10 and TGF-β stand out. As new therapeutic targets, P2X7 and A2A receptors have been suggested, since blocking P2X7 would lead to reduced release of pro-inflammatory cytokines, and blocking A2A would increase activation of cytotoxic T lymphocytes in the context of tumor combat. The association between the immune system and the purinergic system, already known in other types of disease, also presents possibilities for a better understanding of biomolecular processes and therapeutic possibilities in the context of cervical cancer.

Novel possibility for cutaneous melanoma treatment by means of rosmarinic acid action on purinergic signaling

Cancer cases have increased significantly in Brazil and worldwide, with cutaneous melanoma (CM) being responsible for nearly 57,000 deaths in the world. Thus, this review article aims at exploring and proposed hypotheses with respect to the possibility that RA can be a promising and alternative compound to be used as an adjuvant in melanoma treatment, acting on purinergic signaling. The scarcity of articles evidencing the action of this compound in this signaling pathway requires further studies. Considering diverse evidence found in the literature, we hypothesize that RA can be an effective candidate for the treatment of CM acting as a modulating molecule of purinergic cellular pathway through P2X7 blocking, mitigating the Warburg effect, and as antagonic molecule of the P2Y12 receptor, reducing the formation of adhesive molecules that prevent adherence in tumor cells. In this way, our proposals for CM treatment based on targeting purinergic signaling permeate the integral practice, going from intracell to extracell. Undoubtedly, much is still to be discovered and elucidated about this promising compound, this paper being an interesting work baseline to support more research studies.

Autocrine and paracrine purinergic signaling in the most lethal types of cancer

Cancer comprises a collection of diseases that occur in almost any tissue and it is characterized by an abnormal and uncontrolled cell growth that results in tumor formation and propagation to other tissues, causing tissue and organ malfunction and death. Despite the undeniable improvement in cancer diagnostics and therapy, there is an urgent need for new therapeutic and preventive strategies with improved efficacy and fewer side effects. In this context, purinergic signaling emerges as an interesting candidate as a cancer biomarker or therapeutic target. There is abundant evidence that tumor cells have significant changes in the expression of purinergic receptors, which comprise the G-protein coupled P2Y and AdoR families of receptors and the ligand-gated ion channel P2X receptors. Tumor cells also exhibit changes in the expression of nucleotidases and other enzymes involved in nucleotide metabolism, and the concentrations of extracellular nucleotides are significantly higher than those observed in normal cells. In this review, we will focus on the potential role of purinergic signaling in the ten most lethal cancers (lung, breast, colorectal, liver, stomach, prostate, cervical, esophagus, pancreas, and ovary), which together are responsible for more than 5 million annual deaths.

Advances in Intracellular Calcium Signaling Reveal Untapped Targets for Cancer Therapy

Intracellular Ca2+ distribution is a tightly regulated process. Numerous Ca2+ chelating, storage, and transport mechanisms are required to maintain normal cellular physiology. Ca2+-binding proteins, mainly calmodulin and calbindins, sequester free intracellular Ca2+ ions and apportion or transport them to signaling hubs needing the cations. Ca2+ channels, ATP-driven pumps, and exchangers assist the binding proteins in transferring the ions to and from appropriate cellular compartments. Some, such as the endoplasmic reticulum, mitochondria, and lysosomes, act as Ca2+ repositories. Cellular Ca2+ homeostasis is inefficient without the active contribution of these organelles. Moreover, certain key cellular processes also rely on inter-organellar Ca2+ signaling. This review attempts to encapsulate the structure, function, and regulation of major intracellular Ca2+ buffers, sensors, channels, and signaling molecules before highlighting how cancer cells manipulate them to survive and thrive. The spotlight is then shifted to the slow pace of translating such research findings into anticancer therapeutics. We use the PubMed database to highlight current clinical studies that target intracellular Ca2+ signaling. Drug repurposing and improving the delivery of small molecule therapeutics are further discussed as promising strategies for speeding therapeutic development in this area.

Possible role of purinergic signaling in COVID-19

The coronavirus disease (COVID-19), caused by SARS-CoV-2 infection, accounts for more than 2.4 million deaths worldwide, making it the main public health problem in 2020. Purinergic signaling is involved in the pathophysiology of several viral infections which makes the purinergic system a potential target of investigation in COVID-19. During viral infections, the ATP release initiates a cascade that activates purinergic receptors. This receptor activation enhances the secretion of pro-inflammatory cytokines and performs the chemotaxis of macrophages and neutrophils, generating an association between the immune and the purinergic systems. This review was designed to cover the possible functions of purinergic signaling in COVID-19, focusing on the possible role of purinergic receptors such as P2X7 which contributes to cytokine storm and inflammasome NLRP3 activation and P2Y1 that activates the blood coagulation pathway. The possible role of ectonucleotidases, such as CD39 and CD73, which have the function of dephosphorylating ATP in an immunosuppressive component, adenosine, are also covered in detail. Moreover, therapeutic combination or association possibilities targeting purinergic system components are also suggested as a possible useful tool to be tested in future researches, aiming to unveil a novel option to treat COVID-19 patients.

Detection of CD39 and a Highly Glycosylated Isoform of Soluble CD73 in the Plasma of Patients with Cervical Cancer: Correlation with Disease Progression

Persistent infection with high-risk human papillomavirus (HR-HPV) is the main factor in the development of cervical cancer (CC). The presence of immunosuppressive factors plays an important role in the development of this type of cancer. To determine whether CD39 and CD73, which participate in the production of immunosuppressive adenosine (Ado), are involved in the progression of CC, we compared the concentrations and hydrolytic activity of these ectonucleotidases in platelet-free plasma (PFP) samples between patients with low-grade squamous intraepithelial lesions (LSILs) (n = 18), high-grade squamous intraepithelial lesions (HSILs) (n = 12), and CC (n = 19) and normal donors (NDs) (n = 15). The concentrations of CD39 and CD73 in PFP increased with disease progression (r = 0.5929, p < 0.001). The PFP of patients with HSILs or CC showed the highest concentrations of CD39 (2.3 and 2.2 times that of the NDs, respectively) and CD73 (1.7 and 2.68 times that of the NDs, respectively), which were associated with a high capacity to generate Ado from the hydrolysis of adenosine diphosphate (ADP) and adenosine monophosphate (AMP). The addition of POM-1 and APCP, specific inhibitors of CD39 and CD73, respectively, inhibited the ADPase and AMPase activity of PFP by more than 90%. A high level of the 90 kD isoform of CD73 was detected in the PFP of patients with HSILs or CC. Digestion with endoglycosidase H and N-glycanase generated CD73 with weights of approximately 90 kD, 85 kD, 80 kD, and 70 kD. In addition, the levels of transforming grow factor-β (TGF-β) in the PFPs of patients with LSIL, HSIL and CC positively correlated with those of CD39 (r = 0.4432, p < 0.001) and CD73 (r = 0.5786, p < 0.001). These results suggest that persistent infection by HR-HPV and the concomitant production of TGF-β promote the expression of CD39 and CD73 to favor CC progression through Ado generation.