Crosstalk between the peripheral nervous system and breast cancer influences tumor progression

The potential neuro-oncology link of GALR1 protein molecular mechanism in breast cancer: Expression in BT549 and MDA-MB-231 cells and its role in proliferation and migration

The role of GALR1 (mannose bioactive peptide receptor 1) in multiple physiological and pathological processes has attracted much attention, especially in the occurrence and development of cancer. The objective of this study was to examine the expression pattern of GALR1 in BT549 (human breast cancer cells) and MDA-MB-231 (invasive breast cancer cells), and to comprehensively assess its function in cell proliferation and migration, with the aim of uncovering the potential neuro-tumor correlation of GALR1 in cancer. Western blot and real-time quantitative PCR were employed to detect the expression of GALR1 in BT549 and MDA-MB-231 cells. The function of GALR1 was evaluated by cell proliferation assay (e.g., MTT assay) and migration assay (e.g., scratch assay and Transwell migration assay). The expression of GALR1 was down-regulated through RNA interference to investigate its specific role in cell proliferation and migration. The expression of GALR1 was significantly up-regulated in BT549 and MDA-MB-231 cells. Downregulation of GALR1 resulted in a significant decrease in cell proliferation capacity, accompanied by a decrease in migration capacity. Further analysis suggests that GALR1 may act by regulating cell cycle-related proteins and migration-related signaling pathways, such as the PI3K/AKT and MAPK/ERK signaling pathways.

TGFBI promotes EMT and perineural invasion of pancreatic cancer via PI3K/AKT pathway

Pancreatic cancer is a highly lethal malignancy, and perineural invasion (PNI) is a common pathological feature that significantly contributes to poor prognosis. Our research identified TGFBI as a key player in PNI development. The expression of TGFBI in tissue and cancer cells were detected by RT-qPCR, Western blot, Immunohistochemistry, and ELISA. The localization of TGFBI in cells was analyzed by Immunofluorescence staining (IF). The neural invasion ability of cancer cells were assessed by in vitro neural invasion model. Moreover, Western blot was used to investigate epithelial-mesenchymal transition (EMT) markers and PI3K/AKT pathway markers to elucidate the underlying mechanisms. Finally, an in vivo neural invasion model was used to verify the tumorigenic ability of the cancer cells in the sciatic nerve. Our findings highlight that TGFBI is up-regulated in PNI tissue and significantly correlates with poor prognosis in pancreatic cancer patients. Based on in vitro experiments, knockdown of TGFBI reduced neural invasion, as well as EMT, whereas rTGFBI exhibited the reverse effect. Knockdown of TGFBI reduced PI3K/AKT phosphorylation in Capan-2 and CFPAC-1. Moreover, PI3K inhibitor LY294002 was observed to counteract the effects of TGFBI on neural invasion, and EMT in Capan-2 and CFPAC-1. In vivo, knockdown of TGFBI inhibited tumor formation in the sciatic nerve of mice. Finally, we confirmed TGFBI as potential biomarker for PNI and prognosis of pancreatic cancer. Collectively, we concluded that TGFBI activates the PI3K-AKT pathway in pancreatic cancer cells, ultimately promoting EMT and leading to PNI.

Central nervous system and immune cells interactions in cancer: unveiling new therapeutic avenues

Cancer remains a leading cause of mortality worldwide. Despite significant advancements in cancer research, our understanding of its complex developmental pathways remains inadequate. Recent research has clarified the intricate relationship between the central nervous system (CNS) and cancer, particularly how the CNS influences tumor growth and metastasis via regulating immune cell activity. The interactions between the central nervous system and immune cells regulate the tumor microenvironment via various signaling pathways, cytokines, neuropeptides, and neurotransmitters, while also incorporating processes that alter the tumor immunological landscape. Furthermore, therapeutic strategies targeting neuro-immune cell interactions, such as immune checkpoint inhibitors, alongside advanced technologies like brain-computer interfaces and nanodelivery systems, exhibit promise in improving treatment efficacy. This complex bidirectional regulatory network significantly affects tumor development, metastasis, patient immune status, and therapy responses. Therefore, understanding the mechanisms regulating CNS-immune cell interactions is crucial for developing innovative therapeutic strategies. This work consolidates advancements in CNS-immune cell interactions, evaluates their potential in cancer treatment strategies, and provides innovative insights for future research and therapeutic approaches.

Hijacking of the nervous system in cancer: mechanism and therapeutic targets

The activity of neurons in the vicinity of tumors is linked to a spectrum of cellular mechanisms, including the facilitation of tumor cell proliferation, synapse formation, angiogenesis, and macrophage polarization. This review consolidates the current understanding of neuro-oncological regulation, underscoring the nuanced interplay between neurological and oncological processes (termed as Cancer-Neuroscience). First, we elucidated how the nervous system accelerates tumor growth, metastasis, and the tumor microenvironment both directly and indirectly through the action of signaling molecules. Importantly, neural activity is also implicated in modulating the efficacy of therapeutic interventions, including immunotherapy. On the contrary, the nervous system potentially has a suppressive effect on tumorigenesis, further underscoring a dual-edged role of neurons in cancer progression. Consequently, targeting specific signaling molecules within neuro-oncological regulatory pathways could potentially suppress tumor development. Future research is poised to explore the intricate mechanisms governing neuro-tumor interactions more deeply, while concurrently refining treatment strategies for tumors by targeting the crosstalk between cancer and neurons.

Activity-Regulated Cytoskeleton-Associated Protein Gene Expression Is Associated With High Infiltration of Stromal Cells and Immune Cells, but With Less Cancer Cell Proliferation and Better Overall Survival in Estrogen Receptor-Positive/Human Epidermal Growth Factor Receptor 2-Negative Breast Cancers

Background

Peritumoral lidocaine infiltration prior to excision is associated with better survival in breast cancer (BC), which led us to hypothesize that innervation to the tumor affects its biology and patient survival. Activity-regulated cytoskeleton-associated protein (ARC) gene expression is known to be regulated by neuronal activity. Therefore, we studied the clinical relevance of ARC gene expression as a surrogate of neuronal activity in BC.

Methods

Sweden Cancerome Analysis Network - Breast (SCAN-B (GSE96058), n = 3,273) cohort and The Cancer Genome Atlas (TCGA, n = 1,069) were analyzed.

Results

High ARC expression was significantly associated with smaller tumor size, without lymph node metastasis, and less stage IV disease in one cohort, but not validated by the other. Estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) and luminal A expressed significantly higher ARC compared to the other subtypes in both cohorts (P < 0.005). High ARC BC was significantly associated with lower Nottingham histological grade and lower Ki67 gene expression consistently in ER+/HER2- but not triple negative breast cancer (TNBC) in both cohorts (P < 0.001). Cell proliferation-related gene sets in the Hallmark collection (E2F targets, G2M checkpoint, and mitotic spindle) were significantly enriched to low ARC BC in ER+/HER2- but not TNBC in TCGA. The stromal cells (fibroblasts, vascular endothelial cells, and adipocytes) were all significantly infiltrated in high ARC ER+/HER2-, but not in TNBC, except for neurons. Homologous recombination deficiency, intratumor heterogeneity, fraction altered, silent or non-silent mutation rate were all significantly lower in high ARC ER+/HER2- but not TNBC. Although there was no difference in single nucleotide variant or indel neoantigens, tumor infiltrating lymphocytes, and cytolytic activity by ARC expression regardless of subtype, multiple immune cells were significantly infiltrated in high ARC ER+/HER2-, including CD8, CD4 memory cells, helper type II T cells, regulatory T cells, M2 macrophages, and B cells (all P < 0.03 in both cohorts), but not in TNBC. Disease-specific and overall survival were significantly improved in high ARC ER+/HER2- consistently in both cohorts (all P < 0.05), but this was not the case in TNBC.

Conclusion

ARC gene expression was associated with less cancer cell proliferation, high infiltration of stromal cells and immune cells, and better survival in the ER+/HER2- but not TNBC subtype.

Role of TRP Channels in Cancer-Induced Bone Pain

The burden of cancer is growing in almost every country. Bone metastases significantly affect the prognosis and lead to an increase in mortality and morbidity. The management of cancer-induced bone pain (CIBP) still shows various unmet needs. Opioid use is burdened by a number of possible side effects. Moreover, recent progresses in cancer treatment significantly increased the life expectancy of cancer patients, even those with metastatic disease. In this narrative review, we reported the main findings regarding TRP channel function in cancer pain models. TRP cation channels play a key role in different functions of cancer cells, including the regulation of their potential for metastasization, and are the main channels involved in the pathways of pain perception, through peripheral and central effects. Genetic deletion decreased pain sensitivity following tumour cell inoculation. Preclinical data suggest a potential role for modulators of some TRP channels, such as TRPV1, TRPA1, TRPM7 and TRPM8. Clinical results are still scarce; however, the physiological role in modulating bone remodelling and the involvement of TRP channels in preclinical models of bone cancer pain have garnered interest as areas of research in the last few years, as innovative analgesic strategies that may overcome the long-term side effects of opioids.

Mechanisms of Cancer-Induced Bone Pain

Bone is a common site of advanced cancer metastasis, second only to the lungs and liver. Cancer-induced bone pain (CIBP) is a persistent and intense pain that is caused by a combination of inflammatory and neuropathic factors. As CIBP progresses, the degree of pain intensifies. Despite advancements in medical technology, the treatment outcomes of patients with CIBP remain unsatisfactory, and severe pain can typically only be controlled with opioid medications. However, patients treated with opioid medications often develop tolerance. Therefore, they may require dose increases, which can increase the severity of opioid-induced side effects, in turn influencing quality of life. The peripheral mechanisms of CIBP primarily involve bone tissue damage, tumor microenvironment formation, and changes in the dorsal root ganglion. The central mechanisms usually involve biochemical and electrophysiological changes in the spinal cord and brain. The spinal cord is the main processing center for nociceptive signals. When tumor cells produce inflammatory mediators that acidify the microenvironment or damage nerve endings, the spinal cord becomes excessively stimulated, resulting in increased or prolonged pain signals that propagate to the higher central nervous system through the ascending pathway. There are substantial differences in the pain generation mechanisms between CIBP and common inflammatory and neuropathic pain. Therefore, understanding the mechanisms underpinning CIBP development at the level of the spinal cord is crucial for optimizing pain management. This study explores the pathogenesis of CIBP at the level of the spinal cord and describes recently proposed treatment methods for CIBP.

Epidemiology, risk factors and mechanism of breast cancer and atrial fibrillation

Cancer and cardiovascular diseases are leading causes of death worldwide. Among them, breast cancer is one of the most common malignancies in women, while atrial fibrillation is one of the most extensively studied arrhythmias, with significant public health implications. As the global population ages and advancements in cancer treatments continue, the survival rates of breast cancer patients have significantly improved, leading to an increasing coexistence of breast cancer and atrial fibrillation. However, the mechanisms underlying this coexistence remain insufficiently studied, and there is no consensus on the optimal treatment strategies for these patients. This review consolidates existing research to systematically explore the epidemiological characteristics, risk factors, and pathophysiological mechanisms of both breast cancer and atrial fibrillation. It focuses on the unique signaling pathways associated with different molecular subtypes of breast cancer and their potential impact on the mechanisms of atrial fibrillation. Additionally, the relationship between atrial fibrillation treatment medications and breast cancer is discussed. These insights not only provide essential evidence for the precise prevention and management of atrial fibrillation in breast cancer patients but also lay a solid theoretical foundation for interdisciplinary clinical management practices.

Brachial plexopathy due to perineural tumor spread: a retrospective single-center experience of clinical manifestations, diagnosis, treatments, and outcomes

BACKGROUND

Perineural tumor spread (PNTS) to the brachial plexus (BP) is a rare and challenging condition. This study aimed to elucidate the clinical presentations, diagnostic challenges, and outcomes of patients with PNTS to the BP.

METHODS

We retrospectively reviewed patients diagnosed with PNTS to the BP at our institution between January 2009 and June 2024. Clinical characteristics, magnetic resonance imaging (MRI), 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) findings, and treatment outcomes were analyzed.

RESULTS

Seven patients (mean age, 50.3 years) were identified. The primary cancer diagnoses included invasive ductal carcinoma of the breast (n = 3), metaplastic carcinoma of the breast (n = 1), lung adenocarcinoma (n = 2), and papillary thyroid carcinoma (n = 1). The median time from the initial cancer diagnosis to PNTS symptom onset was 71.0 months. All patients initially presented with progressive unilateral pain or paresthesia, followed by motor weakness. Lower trunk plexopathy was the most common electrodiagnostic finding (n = 5). In most patients, BP MRI showed diffuse tubular enlargement and T2 hyperintensity throughout the BP (n = 6), with gadolinium enhancement primarily in the proximal regions (n = 7). 18F-FDG PET/CT demonstrated increased uptake in the BP, most prominently at the cervical spinal root or trunk levels (n = 6). Despite treatment, neurological outcomes were generally poor. Six of the seven patients died after a median follow-up of 19 months post-PNTS diagnosis.

CONCLUSIONS

PNTS to the BP can occur years after initial cancer diagnosis and may signify cancer progression. A high index of suspicion is crucial for timely diagnosis, particularly in patients with cancer and progressive upper extremity symptoms. Comprehensive imaging, including BP MRI and PET/CT, is essential for diagnosis. Despite treatment, prognosis remains poor, highlighting the need for improved diagnostic and therapeutic strategies.

Neurobiology of cancer: Adrenergic signaling and drug repurposing

Cancer neuroscience, as an emerging converging discipline, provides us with new perspectives on the interactions between the nervous system and cancer progression. As the sympathetic nervous system, in particular adrenergic signaling, plays an important role in the regulation of tumor activity at every hierarchical level of life, from the tumor cell to the tumor microenvironment, and to the tumor macroenvironment, it is highly desirable to dissect its effects. Considering the far-reaching implications of drug repurposing for antitumor drug development, such a large number of adrenergic receptor antagonists on the market has great potential as one of the means of antitumor therapy, either as primary or adjuvant therapy. Therefore, this review aims to summarize the impact of adrenergic signaling on cancer development and to assess the status and prospects of intervening in adrenergic signaling as a therapeutic tool against tumors.

Metabolic reprogramming and therapeutic resistance in primary and metastatic breast cancer

Metabolic alterations, a hallmark of cancer, enable tumor cells to adapt to their environment by modulating glucose, lipid, and amino acid metabolism, which fuels rapid growth and contributes to treatment resistance. In primary breast cancer, metabolic shifts such as the Warburg effect and enhanced lipid synthesis are closely linked to chemotherapy failure. Similarly, metastatic lesions often display distinct metabolic profiles that not only sustain tumor growth but also confer resistance to targeted therapies and immunotherapies. The review emphasizes two major aspects: the mechanisms driving metabolic resistance in both primary and metastatic breast cancer, and how the unique metabolic environments in metastatic sites further complicate treatment. By targeting distinct metabolic vulnerabilities at both the primary and metastatic stages, new strategies could improve the efficacy of existing therapies and provide better outcomes for breast cancer patients.

Neural Circuitries between the Brain and Peripheral Solid Tumors

The recent discovery of the pivotal role of the central nervous system in controlling tumor initiation and progression has opened a new field of research. Increasing evidence suggests a bidirectional interaction between the brain and tumors. The brain influences the biological behavior of tumor cells through complex neural networks involving the peripheral nervous system, the endocrine system, and the immune system, whereas tumors can establish local autonomic and sensory neural networks to transmit signals into the central nervous system, thereby affecting brain activity. This review aims to summarize the latest research in brain-tumor cross-talk, exploring neural circuitries between the brain and various peripheral solid tumors, analyzing the roles in tumor development and the related molecular mediators and pathologic mechanisms, and highlighting the critical impact on the understanding of cancer biology. Enhanced understanding of reciprocal communication between the brain and tumors will establish a solid theoretical basis for further research and could open avenues for repurposing psychiatric interventions in cancer treatment.

Measurement of resting energy expenditure and its accuracy in women with breast cancer

BACKGROUND & AIMS

Breast cancer (BC) is frequently linked with obesity, metabolic syndrome, and sarcopenia. Therefore, measuring or accurately estimating resting energy expenditure (REE) is crucial for tailoring nutritional needs, managing weight and prevent under- or over-nutrition. We aimed to measure and compare REE between women with BC and a matched control group. Moreover, the prediction accuracy of selected formulas was evaluated.

METHODS

Women aged ≥18 years with newly diagnosis of BC (stage 0-III) and body mass index (BMI) ≤ 30 kg/m2 were included in this cross-sectional analysis. Anthropometry, indirect calorimetry, and bioelectrical impedance analysis (BIA) were performed. Patients with BC data were compared to healthy women with similar age and BMI range. Measured REE (mREE) was compared against 15 predictive equations. Agreement between methods was evaluated using Bland-Altman analysis.

RESULTS

We included 106 women with BC (age 49.9 ± 11.1 years and BMI 24.5 ± 2.8 kg/m2) and 75 women as control group. There were no differences in age, anthropometry, and BIA variables between groups, except for percentage fat mass. Measured REE values, alone and adjusted for fat-free mass (FFM) and age, were higher in patients with BC compared to controls (+4.3 % and +6.1 %, respectively). Regarding REE prediction, most of the selected equations underestimated mREE. Precision varied widely, with the two Marra equations showing the highest agreement (73 % and 74.5 %) along with the Müller equation (74 %), however, the wide limit of agreement range indicates substantial variability.

CONCLUSIONS

Women with early-stage BC exhibited higher mREE compared to controls, albeit its clinical significance is unknown. None of the selected predictive equations provided accurate and precise REE estimates in this group. Although the Marra equation displayed the highest agreement, further studies are needed to evaluate REE variability and its prediction in women with BC.

Neural control of tumor immunity

Communication between the nervous system and the immune system has evolved to optimally respond to potentially dangerous stimuli both from within and outside the body. Tumors pose a severe threat to an organism and current therapies are insufficient for tumor regression in the majority of cases. Studies show that tumors are innervated by peripheral nerves from the sensory, parasympathetic and sympathetic nervous systems. Interactions between cancer cells, nerves and immune cells regulate overall tumor progression. Clinical studies have indicated the potential of targeting the peripheral nervous system for promoting anti-tumor immune responses. This view point provides an opinion on the current evidence and therapeutic potential of manipulating neuro-immune communications in cancer.

Neuroscience in peripheral cancers: tumors hijacking nerves and neuroimmune crosstalk

Cancer neuroscience is an emerging field that investigates the intricate relationship between the nervous system and cancer, gaining increasing recognition for its importance. The central nervous system governs the development of the nervous system and directly affects brain tumors, and the peripheral nervous system (PNS) shapes the tumor microenvironment (TME) of peripheral tumors. Both systems are crucial in cancer initiation and progression, with recent studies revealing a more intricate role of the PNS within the TME. Tumors not only invade nerves but also persuade them through remodeling to further promote malignancy, creating a bidirectional interaction between nerves and cancers. Notably, immune cells also contribute to this communication, forming a triangular relationship that influences protumor inflammation and the effectiveness of immunotherapy. This review delves into the intricate mechanisms connecting the PNS and tumors, focusing on how various immune cell types influence nerve‒tumor interactions, emphasizing the clinical relevance of nerve‒tumor and nerve‒immune dynamics. By deepening our understanding of the interplay between nerves, cancer, and immune cells, this review has the potential to reshape tumor biology insights, inspire innovative therapies, and improve clinical outcomes for cancer patients.

Research trends on cancer neuroscience: a bibliometric and visualized analysis

Background

Recently, cancer neuroscience has become the focus for scientists. Interactions between the nervous system and cancer (both systemic and local) can regulate tumorigenesis, progression, treatment resistance, compromise of anti-cancer immunity, and provocation of tumor-promoting inflammation. We assessed the related research on cancer neuroscience through bibliometric analysis and explored the research status and hotspots from 2020 to 2024.

Methods

Publications on cancer neuroscience retrieved from the Web of Science Core Collection. CiteSpace, VOSviewer, and Scimago Graphica were used to analyze and visualize the result.

Results

A total of 744 publications were retrieved, with an upward trend in the overall number of articles published over the last 5 years. As it has the highest number of publications (n = 242) and citations (average 13.63 citations per article), the United States holds an absolute voice in the field of cancer neuroscience. The most productive organizations and journals were Shanghai Jiaotong University (n = 24) and Cancers (n = 45), respectively. Monje M (H-index = 53), Hondermarck H (H-index = 42), and Amit M (H-index = 39) were the three researchers who have contributed most to the field. From a global perspective, research hotspots in cancer neuroscience comprise nerve/neuron-tumor cell interactions, crosstalk between the nervous system and other components of the tumor microenvironment (such as immune cells), as well as the impact of tumors and tumor therapies on nervous system function.

Conclusion

The United States and European countries are dominating the field of cancer neuroscience, while developing countries such as China are growing rapidly but with limited impact. The next focal point in this field is likely to be neurotrophic factors. Cancer neuroscience is still in its infancy, which means that many of the interactions and mechanisms between the nervous system and cancer are not yet fully understood. Further investigation is necessary to probe the interactions of the nervous system with cancer cell subpopulations and other components of the tumor microenvironment.

The intersection of the nervous system and breast cancer

Breast cancer (BC) represents a paradigm of heterogeneity, manifesting as a spectrum of molecular subtypes with divergent clinical trajectories. It is fundamentally characterized by the aberrant proliferation of malignant cells within breast tissue, a process modulated by a myriad of factors that govern its progression. Recent endeavors outline the interplay between BC and the nervous system, illuminate the complex symbiosis between neural structures and neoplastic cells, and elucidate nerve dependence as a cornerstone of BC progression. This includes the neural modulations on immune response, neurovascular formation, and multisystem interactions. Such insights have unveiled the critical impact of neural elements on tumor dynamics and patient prognosis. This revelation beckons a deeper exploration into the neuro-oncological interface, potentially unlocking novel therapeutic vistas. This review endeavors to delineate the intricate mechanisms between the nervous system and BC, aiming to accentuate the implications and therapeutic strategies of this intersection for tumor evolution and the formulation of innovative therapeutic approaches.

Augustus Waller's foresight realized: SARM1 in peripheral neuropathies

Peripheral neuropathy is a common neurodegenerative condition characterized by numbness, tingling, pain, and weakness that frequently starts in the distal limbs. Arising from multiple etiologies, many peripheral neuropathies exhibit a slowly progressive course due to axon degeneration for which no effective treatments exist. During the past decade, numerous crucial insights into mechanisms of axon degeneration in peripheral neuropathies emerged from experiments involving nerve-cutting procedures, revealing the central role of the SARM1 axon degeneration pathway in both. Here I review commonalities and differences in the role of SARM1 after nerve cut and in several acquired and inherited peripheral neuropathies. This new knowledge now paves the way for the development of therapeutics that directly address root causes of various kinds of neuropathies.

Nerve-tumor crosstalk in tumor microenvironment: From tumor initiation and progression to clinical implications

The autonomic nerve system (ANS) innervates organs and tissues throughout the body and maintains functional balance among various systems. Further investigations have shown that excessive activation of ANS not only causes disruption of homeostasis, but also may promote tumor formation. In addition, the dynamic interaction between nerve and tumor cells in the tumor microenvironment also regulate tumor progression. On the one hand, nerves are passively invaded by tumor cells, that is, perineural invasion (PNI). On the other hand, compared with normal tissues, tumor tissues are subject to more abundant innervation, and nerves can influence tumor progression through regulating tumor proliferation, metastasis and drug resistance. A large number of studies have shown that nerve-tumor crosstalk, including PNI and innervation, is closely related to the prognosis of patients, and contributes to the formation of cancer pain, which significantly deteriorates the quality of life for patients. These findings suggest that nerve-tumor crosstalk represents a potential target for anti-tumor therapies and the management of cancer pain in the future. In this review, we systematically describe the mechanism by which nerve-tumor crosstalk regulates tumorigenesis and progression.

Stiffened tumor microenvironment enhances perineural invasion in breast cancer via integrin signaling

BACKGROUND

Accumulating studies have shown that tumors are regulated by nerves, and there is abundant nerve infiltration in the tumor microenvironment. Many solid tumors including breast cancer (BRCA) have different degrees of perineural invasion (PNI), which is closely related to the tumor occurrence and progression. However, the regulatory mechanism of PNI in BRCA remains largely unexplored.

METHODS

PNI-related molecular events are analyzed by the RNAseq data of BRCA samples deposited in The Cancer Genome Atlas (TCGA) database. Extracellular matrix (ECM) components within the tumor microenvironment are analyzed by immunohistochemical staining of α-SMA, Sirius red staining, and Masson trichrome staining. Soft and stiff matrix gels, living cell imaging, and dorsal root ganglion (DRG) coculture assay are used to monitor cancer cell invasiveness towards nerves. Western blotting, qRT-PCR, enzyme-linked immunosorbent assay combined with neutralizing antibody and small molecular inhibitors are employed to decode molecular mechanisms.

RESULTS

Comparative analysis that the ECM was significantly associated with PNI status in the TCGA cohort. BRCA samples with higher α-SMA activity, fibrillar collagen, and collagen content had higher frequency of PNI. Compared with soft matrix, BRCA cells cultured in stiff matrix not only displayed higher cell invasiveness to DRG neurons but also had significant neurotrophic effects. Mechanistically, integrin β1 was identified as a functional receptor to the influence of stiff matrix on BRCA cells. Moreover, stiffened matrix-induced activation of integrin β1 transduces FAK-YAP signal cascade, which enhances cancer invasiveness and the neurotrophic effects. In clinical setting, PNI-positive BRCA samples had higher expression of ITGB1, phosphorylated FAK, YAP, and NGF compared with PNI-negative BRCA samples.

CONCLUSIONS

Our findings suggest that stiff matrix induces expression of pro-metastatic and neurotrophic genes through integrin β1-FAK-YAP signals, which finally facilitates PNI in BRCA. Thus, our study provides a new mechanism for PNI in BRCA and highlights nerve-based tumor treatment strategies.

Cellular interactions in tumor microenvironment during breast cancer progression: new frontiers and implications for novel therapeutics

The breast cancer tumor microenvironment (TME) is dynamic, with various immune and non-immune cells interacting to regulate tumor progression and anti-tumor immunity. It is now evident that the cells within the TME significantly contribute to breast cancer progression and resistance to various conventional and newly developed anti-tumor therapies. Both immune and non-immune cells in the TME play critical roles in tumor onset, uncontrolled proliferation, metastasis, immune evasion, and resistance to anti-tumor therapies. Consequently, molecular and cellular components of breast TME have emerged as promising therapeutic targets for developing novel treatments. The breast TME primarily comprises cancer cells, stromal cells, vasculature, and infiltrating immune cells. Currently, numerous clinical trials targeting specific TME components of breast cancer are underway. However, the complexity of the TME and its impact on the evasion of anti-tumor immunity necessitate further research to develop novel and improved breast cancer therapies. The multifaceted nature of breast TME cells arises from their phenotypic and functional plasticity, which endows them with both pro and anti-tumor roles during tumor progression. In this review, we discuss current understanding and recent advances in the pro and anti-tumoral functions of TME cells and their implications for developing safe and effective therapies to control breast cancer progress.

A brain-tumor neural circuit controls breast cancer progression in mice

Tumor burden, considered a common chronic stressor, can cause widespread anxiety. Evidence suggests that cancer-induced anxiety can promote tumor progression, but the underlying neural mechanism remains unclear. Here, we used neuroscience and cancer tools to investigate how the brain contributes to tumor progression via nerve-tumor crosstalk in a mouse model of breast cancer. We show that tumor-bearing mice exhibited significant anxiety-like behaviors and that corticotropin-releasing hormone (CRH) neurons in the central medial amygdala (CeM) were activated. Moreover, we detected newly formed sympathetic nerves in tumors, which established a polysynaptic connection to the brain. Pharmacogenetic or optogenetic inhibition of CeMCRH neurons and the CeMCRH→lateral paragigantocellular nucleus (LPGi) circuit significantly alleviated anxiety-like behaviors and slowed tumor growth. Conversely, artificial activation of CeMCRH neurons and the CeMCRH→LPGi circuit increased anxiety and tumor growth. Importantly, we found alprazolam, an antianxiety drug, to be a promising agent for slowing tumor progression. Furthermore, we show that manipulation of the CeMCRH→LPGi circuit directly regulated the activity of the intratumoral sympathetic nerves and peripheral nerve-derived norepinephrine, which affected tumor progression by modulating antitumor immunity. Together, these findings reveal a brain-tumor neural circuit that contributes to breast cancer progression and provide therapeutic insights for breast cancer.

Comprehensive pan‑cancer analysis of potassium voltage-gated channel Q4 (KCNQ4) gene across multiple human malignant tumors

A large number of studies indicate that Potassium Voltage-Gated Channel Q4 (KCNQ4) gene is the cause of non-syndromic hearing loss, but there are few studies investigating the role of KCNQ4 in cancers and scarcity of comprehensive analysis of its involvement in the diagnosis, methylation, mutation, prognosis of various cancer types. Therefore, the aim of this study is to examine the anticancerous and immune effects of KCNQ4 in various cancers and its potential value in breast cancer. In this study, we explored the potential role of KCNQ4 in cancers using public databases and the R software for bioinformatics analysis. The results showed that the low expression of KCNQ4 across specific cancer types was positively associated with low mutation frequency and methylation, and the improved survival. Eight small molecule compounds were identified that could potentially target KCNQ4. In addition, immunohistochemistry confirmed that the KCNQ4 expression was low in breast cancer. In vitro experiments confirmed that overexpression of KCNQ4 inhibited cell migration and invasion and promoted apoptosis. In summary, our comprehensive pan-cancer analysis highlights the potential of KCNQ4 as a cancer marker, and can be used as an auxiliary prognostic indicator and an indicator for immunotherapy in certain tumor types.

Carcinogenesis and Metastasis: Focus on TRPV1-Positive Neurons and Immune Cells

Both sensory neurons and immune cells, albeit at markedly different levels, express the vanilloid (capsaicin) receptor, Transient Receptor Potential, Vanilloid-1 (TRPV1). Activation of TRPV1 channels in sensory afferent nerve fibers induces local effector functions by releasing neuropeptides (most notably, substance P) which, in turn, trigger neurogenic inflammation. There is good evidence that chronic activation or inactivation of this inflammatory pathway can modify tumor growth and metastasis. TRPV1 expression was also demonstrated in a variety of mammalian immune cells, including lymphocytes, dendritic cells, macrophages and neutrophils. Therefore, the effects of TRPV1 agonists and antagonists may vary depending on the prominent cell type(s) activated and/or inhibited. Therefore, a comprehensive understanding of TRPV1 activity on immune cells and nerve endings in distinct locations is necessary to predict the outcome of therapies targeting TRPV1 channels. Here, we review the neuro-immune modulation of cancer growth and metastasis, with focus on the consequences of TRPV1 activation in nerve fibers and immune cells. Lastly, the potential use of TRPV1 modulators in cancer therapy is discussed.

A CRISPR/Cas9-Based Assay for High-Throughput Studies of Cancer-Induced Innervation

The aggressive nature of certain cancers and their adverse effects on patient outcomes have been linked to cancer innervation, where neurons infiltrate and differentiate within the cancer stroma. Recently we demonstrated how cancer plasticity and TGFβ signaling could promote breast cancer innervation that is associated with increased cancer aggressivity. Despite the promising potential of cancer innervation as a target for anti-cancer therapies, there is currently a significant lack of effective methods to study cancer-induced neuronal differentiation, hindering the development of high-throughput approaches for identifying new targets or pharmacological inhibitors against cancer innervation. To overcome this challenge, we used CRISPR-based endogenous labeling of the neuronal marker β3-tubulin in neuronal precursors to investigate cancer-induced neuronal differentiation in nerve-cancer cocultures and provide a tool that allows for better standardization and reproducibility of studies about cancer-induced innervation. Our approach demonstrated that β3-tubulin gene editing did not affect neuronal behavior and enabled accurate reporting of cancer-induced neuronal differentiation dynamics in high-throughput settings, which makes this approach suitable for screening large cohorts of cells or testing various biological contexts. In a more context-based approach, by combining this method with a cell model of breast cancer epithelial-mesenchymal transition, we revealed the role of cancer cell plasticity in promoting neuronal differentiation, suggesting that cancer innervation represents an underexplored path for epithelial-mesenchymal transition-mediated cancer aggressivity.

Magnetic Nanomaterials Mediate Electromagnetic Stimulations of Nerves for Applications in Stem Cell and Cancer Treatments

Although some progress has been made in the treatment of cancer, challenges remain. In recent years, advancements in nanotechnology and stem cell therapy have provided new approaches for use in regenerative medicine and cancer treatment. Among them, magnetic nanomaterials have attracted widespread attention in the field of regenerative medicine and cancer; this is because they have high levels of safety and low levels of invasibility, promote stem cell differentiation, and affect biological nerve signals. In contrast to pure magnetic stimulation, magnetic nanomaterials can act as amplifiers of an applied electromagnetic field in vivo, and by generating different effects (thermal, electrical, magnetic, mechanical, etc.), the corresponding ion channels are activated, thus enabling the modulation of neuronal activity with higher levels of precision and local modulation. In this review, first, we focused on the relationship between biological nerve signals and stem cell differentiation, and tumor development. In addition, the effects of magnetic nanomaterials on biological neural signals and the tumor environment were discussed. Finally, we introduced the application of magnetic-nanomaterial-mediated electromagnetic stimulation in regenerative medicine and its potential in the field of cancer therapy.