Chemoresistance in Breast Cancer Patients Associated With Changes in P2X7 and A2A Purinergic Receptors in CD8+ T Lymphocytes

ATP ion channel-type P2X purinergic receptors as a key regulatory molecule in breast cancer progression

Studies have confirmed that ATP ion channel P2X purinergic receptors play a key role in tumor growth and metastasis. Similarly, P2X purinergic receptors can be used as a favorable regulatory molecule of breast cancer cells to participate in the progression of breast cancer. There are abundant ATP and its cleavage products in breast cancer microenvironment, which can be used as natural activators of P2X purinergic receptors. P2X purinergic receptors play a role in regulating the growth and metastasis of breast cancer cells by mediating signal transduction, growth regulation and immune cell activity in microenvironment. However, the application of P2X purinergic receptors antagonist has the pharmacological characteristics of inhibiting the progression of breast cancer cells. Among P2X purinergic receptors, there is a close relationship between P2X7 receptor and breast cancer patients. P2X purinergic receptors can be used as a biological marker for breast cancer patients. In this paper, we discuss the functional role and regulatory molecular mechanism of P2X purinergic receptors in the progression of breast cancer. The pharmacological effects of P2X purinergic receptors selective antagonist on the growth, metastasis and invasion of breast cancer cells were further discussed. Therefore, P2X purinergic receptors can be used as a key regulatory molecule of breast cancer and a pharmacological target for potential therapy.

The Role of Adenosine in Overcoming Resistance in Sarcomas

Resistance to systemic therapies in sarcomas poses a significant challenge to improving clinical outcomes. Recent research has concentrated on the tumor microenvironment's role in sarcoma progression and treatment resistance. This microenvironment comprises a variety of cell types and signaling molecules that influence tumor behavior, including proliferation, metastasis, and resistance to therapy. Adenosine, abundant in the tumor microenvironment, has been implicated in promoting immunosuppression and chemoresistance. Targeting adenosine receptors and associated pathways offers a novel approach to enhancing immune responses against tumors, potentially improving immunotherapy outcomes in cancers, including sarcomas. Manipulating adenosine signaling also shows promise in overcoming chemotherapy resistance in these tumors. Clinical trials investigating adenosine receptor antagonists in sarcomas have fueled interest in this pathway for sarcoma treatment. Ultimately, a comprehensive understanding of the tumor and vascular microenvironments, as well as the adenosine pathway, may open new avenues for improving treatment outcomes and overcoming resistance in sarcoma. Further studies and clinical trials are crucial to validate these findings and optimize therapeutic strategies, particularly for osteosarcoma. This study provides a literature review exploring the potential role of the adenosine pathway in sarcomas.

Emerging measurements for tumor-infiltrating lymphocytes in breast cancer

Tumor-infiltrating lymphocytes are a general term for lymphocytes or immune cells infiltrating the tumor microenvironment. Numerous studies have demonstrated tumor-infiltrating lymphocytes to be robust prognostic and predictive biomarkers in breast cancer. Recently, immune checkpoint inhibitors, which directly target tumor-infiltrating lymphocytes, have become part of standard of care treatment for triple-negative breast cancer. Surprisingly, tumor-infiltrating lymphocytes quantified by conventional methods do not predict response to immune checkpoint inhibitors, which highlights the heterogeneity of tumor-infiltrating lymphocytes and the complexity of the immune network in the tumor microenvironment. Tumor-infiltrating lymphocytes are composed of diverse immune cell populations, including cytotoxic CD8-positive T lymphocytes, B cells and myeloid cells. Traditionally, tumor-infiltrating lymphocytes in tumor stroma have been evaluated by histology. However, the standardization of this approach is limited, necessitating the use of various novel technologies to elucidate the heterogeneity in the tumor microenvironment. This review outlines the evaluation methods for tumor-infiltrating lymphocytes from conventional pathological approaches that evaluate intratumoral and stromal tumor-infiltrating lymphocytes such as immunohistochemistry, to the more recent advancements in computer tissue imaging using artificial intelligence, flow cytometry sorting and multi-omics analyses using high-throughput assays to estimate tumor-infiltrating lymphocytes from bulk tumor using immune signatures or deconvolution tools. We also discuss higher resolution technologies that enable the analysis of tumor-infiltrating lymphocytes heterogeneity such as single-cell analysis and spatial transcriptomics. As we approach the era of personalized medicine, it is important for clinicians to understand these technologies.

Potential of the postoperative lymphocyte-to-monocyte and monocyte-to-red blood cell ratio in predicting locoregional and distant metastases after breast cancer resection - Retrospective study

PURPOSE

Breast cancer is the most common malignancy with high recurrence and mortality rates in women. There are still insufficient biomarkers to predict disease prognosis. Therefore, the present study aimed to investigate the clinical significance of postoperative hematologic parameters and their derivatives in patients with breast cancer who underwent tumor resection.

PATIENTS AND METHODS

The clinicopathological and laboratory data of 90 female breast cancer patients who underwent surgical treatment in the Greater Poland Cancer Center in Poznan from December 2015 to November 2017 were retrospectively analyzed. Postoperative hematologic parameters, including neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), monocyte-to-red blood cell ratio (MRR), lymphocyte-to-red blood cell ratio (LRR), platelet-to-red blood cell ratio (PRR) were evaluated in recurrence and non-recurrence group. Receiver-operating characteristic (ROC) curve analysis was used to assess the optimal cutoff value of postoperative hematologic parameters for tumor recurrence. The association of postoperative hematologic parameters with disease-free survival (DFS) was investigated by the Kaplan-Meier method and Cox regression analysis.

RESULTS

Patients with local, regional, or distant metastases accounted for 14% of the total. The postoperative monocyte count and MRR were significantly elevated, whereas postoperative LMR was statistically decreased in the recurrence group. Univariate and multivariate Cox analysis revealed that postoperative LMR ≤3.044 and postoperative MRR >0.1398 were associated with significantly shorter DFS.

CONCLUSION

Our results revealed that both postoperative LMR and MRR are independent predictors of DFS in breast cancer patients. Large-scale prospective investigations are needed to validate our findings.

Multiomics technologies for comprehensive tumor microenvironment analysis in triple-negative breast cancer under neoadjuvant chemotherapy

Triple-negative breast cancer (TNBC) is one of the most aggressive breast cancer subtypes and is characterized by abundant infiltrating immune cells within the microenvironment. As standard care, chemotherapy remains the fundamental neoadjuvant treatment in TNBC, and there is increasing evidence that supplementation with immune checkpoint inhibitors may potentiate the therapeutic efficiency of neoadjuvant chemotherapy (NAC). However, 20-60% of TNBC patients still have residual tumor burden after NAC and require additional chemotherapy; therefore, it is critical to understand the dynamic change in the tumor microenvironment (TME) during treatment to help improve the rate of complete pathological response and long-term prognosis. Traditional methods, including immunohistochemistry, bulk tumor sequencing, and flow cytometry, have been applied to elucidate the TME of breast cancer, but the low resolution and throughput may overlook key information. With the development of diverse high-throughput technologies, recent reports have provided new insights into TME alterations during NAC in four fields, including tissue imaging, cytometry, next-generation sequencing, and spatial omics. In this review, we discuss the traditional methods and the latest advances in high-throughput techniques to decipher the TME of TNBC and the prospect of translating these techniques to clinical practice.

Inhibition of CD73 expression or A2AR blockade reduces MRP1 expression and increases the sensitivity of cervical cancer cells to cisplatin

Recently, a link between the biological activity of CD73 in solid tumors and multidrug resistance protein (MRP) has been proposed. Cisplatin (CP) is the most widely used anticancer agent to treat advanced and recurrent cervical cancer (CC). However, multidrug resistance protein-1 (MRP1) is overexpressed in approximately 85% of these tumors and has been strongly associated with cisplatin resistance (CPR). In this study, we examine the involvement of CD73 and the interaction of adenosine (ADO) with its receptors (ARs) in MRP1 expression in CC cells. We found that ADO positively modulates MRP1 expression in CC cells in a dose-dependent manner. The inhibition of CD73 expression with a CD73-targeted siRNA and A2AR blockade with the selective antagonist ZM241385 significantly decreased MRP1 expression and the extrusive capacity of CC cells, making them significantly more sensitive to CP treatment than cancer cells treated with MK-751, a specific MRP1 inhibitor. These results suggest CD73 inhibition or blocking ADO signaling through A2AR could be strategies to reverse CPR in patients with advanced or recurrent CC, which is characterized by very low response rates to CP (10%-20%).

Emerging roles of purinergic signaling in anti-cancer therapy resistance

Cancer is a complex disease with a rapid growing incidence and often characterized by a poor prognosis. Although impressive advances have been made in cancer treatments, resistance to therapy remains a critical obstacle for the improvement of patients outcome. Current treatment approaches as chemo-, radio-, and immuno-therapy deeply affect the tumor microenvironment (TME), inducing an extensive selective pressure on cancer cells through the activation of the immune system, the induction of cell death and the release of inflammatory and damage-associated molecular patterns (DAMPS), including nucleosides (adenosine) and nucleotides (ATP and ADP). To survive in this hostile environment, resistant cells engage a variety of mitigation pathways related to metabolism, DNA repair, stemness, inflammation and resistance to apoptosis. In this context, purinergic signaling exerts a pivotal role being involved in mitochondrial function, stemness, inflammation and cancer development. The activity of ATP and adenosine released in the TME depend upon the repertoire of purinergic P2 and adenosine receptors engaged, as well as, by the expression of ectonucleotidases (CD39 and CD73) on tumor, immune and stromal cells. Besides its well established role in the pathogenesis of several tumors and in host–tumor interaction, purinergic signaling has been recently shown to be profoundly involved in the development of therapy resistance. In this review we summarize the current advances on the role of purinergic signaling in response and resistance to anti-cancer therapies, also describing the translational applications of combining conventional anticancer interventions with therapies targeting purinergic signaling.

Purinergic receptors are a key bottleneck in tumor metabolic reprogramming: The prime suspect in cancer therapeutic resistance

ATP and other nucleoside phosphates have specific receptors named purinergic receptors. Purinergic receptors and ectonucleotidases regulate various signaling pathways that play a role in physiological and pathological processes. Extracellular ATP in the tumor microenvironment (TME) has a higher level than in normal tissues and plays a role in cancer cell growth, survival, angiogenesis, metastasis, and drug resistance. In this review, we investigated the role of purinergic receptors in the development of resistance to therapy through changes in tumor cell metabolism. When a cell transforms to neoplasia, its metabolic processes change. The metabolic reprogramming modified metabolic feature of the TME, that can cause impeding immune surveillance and promote cancer growth. The purinergic receptors contribute to therapy resistance by modifying cancer cells' glucose, lipid, and amino acid metabolism. Limiting the energy supply of cancer cells is one approach to overcoming resistance. Glycolysis inhibitors which reduce intracellular ATP levels may make cancer cells more susceptible to anti-cancer therapies. The loss of the P2X7R through glucose intolerance and decreased fatty acid metabolism reduces therapeutic resistance. Potential metabolic blockers that can be employed in combination with other therapies will aid in the discovery of new anti-cancer immunotherapy to overcome therapy resistance. Therefore, therapeutic interventions that are considered to inhibit cancer cell metabolism and purinergic receptors simultaneously can potentially reduce resistance to treatment.

Immune-Related Genes to Construct a Novel Prognostic Model of Breast Cancer: A Chemosensitivity-Based Study

Chemotherapy combined with surgery is effective for patients with breast cancer (BC). However, chemoresistance restricts the effectiveness of BC treatment. Immune microenvironmental changes are of pivotal importance for chemotherapy responses. Thus, we sought to construct and validate an immune prognostic model based on chemosensitivity status in BC. Here, immune-related and chemosensitivity-related genes were obtained from GSE25055. Then, univariate analysis was employed to identify prognostic-related gene pairs from the intersection of the two parts of the genes, and modified least absolute shrinkage and selection operator (LASSO) analysis was performed to build a prognostic model. Furthermore, we investigated the efficiency of this model from various perspectives, and further validation was performed using the Cancer Genome Atlas (TCGA) cohorts. We identified seven immune and chemosensitivity-related gene pairs and incorporated them into the Cox regression model. After multilevel validation, the risk model was found to be closely related to the survival rate, various clinical characteristics, tumor mutation burden (TMB) score, immune checkpoints, and response to chemotherapeutic drugs. In addition, the model was verified to exhibit predictive capacity as an independent factor over other candidate clinical features. Notably, the constructed nomogram was more accurate than any single factor. Altogether, the risk score model and the nomogram have potential predictive value and may have important practical implications.