Improved survival outcomes with the incidental use of beta-blockers among patients with non-small-cell lung cancer treated with definitive radiation therapy

The multifaceted role of beta-blockers in overcoming cancer progression and drug resistance: Extending beyond cardiovascular disorders

Beta-blockers are commonly used medications that antagonize β-adrenoceptors, reducing sympathetic nervous system activity. Emerging evidence suggests that beta-blockers may also have anticancer effects and help overcome drug resistance in cancer treatment. This review summarizes the contribution of different isoforms of beta-adrenoceptors in cancer progression, the current preclinical and clinical data on associations between beta-blockers use and cancer outcomes, as well as their ability to enhance responses to chemotherapy and other standard therapies. We discuss proposed mechanisms, including effects on angiogenesis, metastasis, cancer stem cells, and apoptotic pathways. Overall, results from epidemiological studies and small clinical trials largely indicate the beneficial effects of beta-blockers on cancer progression and drug resistance. However, larger randomized controlled trials are needed to firmly establish their clinical efficacy and optimal utilization as adjuvant agents in cancer therapy.

Multiple cancer cell types release LIF and Gal3 to hijack neural signals

Neural signals can significantly influence cancer prognosis. However, how cancer cells may proactively modulate the nervous system to benefit their own survival is incompletely understood. In this study, we report an overlapping pattern of brain responses, including that in the paraventricular nucleus of the hypothalamus, in multiple mouse models of peripheral cancers. A multi-omic screening then identifies leukemia inhibitory factor (LIF) and galectin-3 (Gal3) as the key cytokines released by these cancer cell types to trigger brain activation. Importantly, increased plasma levels of these two cytokines are observed in patients with different cancers. We further demonstrate that pharmacologic or genetic blockage of cancer cell-derived LIF or Gal3 signaling abolishes the brain responses and strongly inhibits tumor growth. In addition, ablation of peripheral sympathetic actions can similarly restore antitumor immunity. These results have elucidated a novel, shared mechanism of multiple cancer cell types hijacking the nervous system to promote tumor progression.

Pathological mechanisms of cold and mechanical stress in modulating cancer progression

Environmental temperature and cellular mechanical force are the inherent factors that participate in various biological processes and regulate cancer progress, which have been hot topics worldwide. They occupy a dominant part in the cancer tissues through different approaches. However, extensive investigation regarding pathological mechanisms in the carcinogenic field. After research, we found cold stress via two means to manipulate tumors: neuroscience and mechanically sensitive ion channels (MICHs) such as TRP families to regulate the physiological and pathological activities. Excessive cold stimulation mediated neuroscience acting on every cancer stage through the hypothalamus-pituitary-adrenocorticoid (HPA) to reach the target organs. Comparatively speaking, mechanical force via Piezo of MICHs controls cancer development. The progression of cancer depends on the internal activation of proto-oncogenes and the external tumorigenic factors; the above two means eventually lead to genetic disorders at the molecular level. This review summarizes the interaction of bidirectional communication between them and the tumor. It covers the main processes from cytoplasm to nucleus related to metastasis cascade and tumor immune escape.

The relationship between the tumor and its innervation: historical, methodical, morphological, and functional assessments - A minireview

The acceptance of the tumor as a non-isolated structure within the organism has opened a space for the study of a wide spectrum of potential direct and indirect interactions, not only between the tumor tissue and its vicinity, but also between the tumor and its macroenvironment, including the nervous system. Although several lines of evidence have implicated the nervous system in tumor growth and progression, for many years, researchers believed that tumors lacked innervation and the notion of indirect neuro-neoplastic interactions via other systems (e.g., immune, or endocrine) predominated. The original idea that tumors are supplied not only by blood and lymphatic vessels, but also autonomic and sensory nerves that may influence cancer progression, is not a recent phenomenon. Although in the past, mainly due to the insufficiently sensitive methodological approaches, opinions regarding the presence of nerves in tumors were inconsistent. However, data from the last decade have shown that tumors are able to stimulate the formation of their own innervation by processes called neo-neurogenesis and neo-axonogenesis. It has also been shown that tumor infiltrating nerves are not a passive, but active components of the tumor microenvironment and their presence in the tumor tissue is associated with an aggressive tumor phenotype and correlates with poor prognosis. The aim of the present review was to 1) summarize the available knowledge regarding the course of tumor innervation, 2) present the potential mechanisms and pathways for the possible induction of new nerve fibers into the tumor microenvironment, and 3) highlight the functional significance/consequences of the nerves infiltrating the tumors.

Increased sympathetic nervous system impairs prognosis in lung cancer patients: a scoping review of clinical studies

Aim

To summarize current knowledge, gaps, quality of the evidence and show main results related to the role of the autonomic nervous system in lung cancer.

Methods

Studies were identified through electronic databases (PubMed, Scopus, Embase and Cochrane Library) in October 2023, and a descriptive analysis was performed. Twenty-four studies were included, and most were observational.

Results

Our data indicated an increased expression of β-2-adrenergic receptors in lung cancer, which was associated with poor prognosis. However, the use of β-blockers as an add-on to standard treatment promoted enhanced overall survival, recurrence-free survival and reduced metastasis occurrence.

Conclusion

Although the results herein seem promising, future research using high-quality prospective clinical trials is required to draw directions to guide clinical interventions.

Trial watch: beta-blockers in cancer therapy

Compelling evidence supports the hypothesis that stress negatively impacts cancer development and prognosis. Irrespective of its physical, biological or psychological source, stress triggers a physiological response that is mediated by the hypothalamic-pituitary-adrenal axis and the sympathetic adrenal medullary axis. The resulting release of glucocorticoids and catecholamines into the systemic circulation leads to neuroendocrine and metabolic adaptations that can affect immune homeostasis and immunosurveillance, thus impairing the detection and eradication of malignant cells. Moreover, catecholamines directly act on β-adrenoreceptors present on tumor cells, thereby stimulating survival, proliferation, and migration of nascent neoplasms. Numerous preclinical studies have shown that blocking adrenergic receptors slows tumor growth, suggesting potential clinical benefits of using β-blockers in cancer therapy. Much of these positive effects of β-blockade are mediated by improved immunosurveillance. The present trial watch summarizes current knowledge from preclinical and clinical studies investigating the anticancer effects of β-blockers either as standalone agents or in combination with conventional antineoplastic treatments or immunotherapy.

The association between the neuroendocrine system and the tumor immune microenvironment: Emerging directions for cancer immunotherapy

This review summarizes emerging evidence that the neuroendocrine system is involved in the regulation of the tumor immune microenvironment (TIME) to influence cancer progression. The basis of the interaction between the neuroendocrine system and cancer is usually achieved by the infiltration of nerve fibers into the tumor tissue, which is called neurogenesis; the migration of cancer cells toward nerve fibers, which is called perineural invasion (PNI), and the neurotransmitters. In addition to the traditional role of neurotransmitters in neural communications, neurotransmitters are increasingly recognized as mediators of crosstalk between the nervous system, cancer cells, and the immune system. Recent studies have revealed that not only nerve fibers but also cancer cells and immune cells within the TIME can secrete neurotransmitters, exerting influence on both neurons and themselves. Furthermore, immune cells infiltrating the tumor environment have been found to express a wide array of neurotransmitter receptors. Hence, targeting these neurotransmitter receptors may promote the activity of immune cells in the tumor microenvironment and exert anti-tumor immunity. Herein, we discuss the crosstalk between the neuroendocrine system and tumor-infiltrating immune cells, which may provide feasible cancer immunotherapy options.

Investigating Carvedilol's Repurposing for the Treatment of Non-Small Cell Lung Cancer via Aldehyde Dehydrogenase Activity Modulation in the Presence of β-Adrenergic Agonists

Repurposing existing drugs appears to be a potential solution for addressing the challenges in the treatment of non-small cell lung cancer (NSCLC). β-adrenoceptor antagonist drugs (β-blockers) have tumor-inhibiting effects, making them promising candidates for potential NSCLC treatment. This study investigates the anticancer potential of a subset of β-blockers in NSCLC cell lines; A549 and H1299. Additionally, it investigates the underlying mechanism behind β-blockers' anticancer effect by influencing a potential novel target named aldehyde dehydrogenase (ALDH). The MTT assay assessed β-blockers' cytotoxicity on both cell lines, while Western blot and NADH fluorescence assays evaluated their influence on ALDH protein expression and activity. Carvedilol (CAR) was the most effective blocker in reducing cell survival of A549 and H1299 with IC50 of 18 µM and 13.7 µM, respectively. Significantly, CAR led to a 50% reduction in ALDH expression and 80% decrease in ALDH activity in A549 cells, especially when combined with β-agonists, in comparison to the control. This effect might be attributed to β-agonist blockade or an alternative pathway. This novel finding adds to our understanding of CAR's multifaceted anticancer properties, implying that combining CAR with β-agonists could be a useful strategy for lung cancer treatment.

The neural addiction of cancer

The recently uncovered key role of the peripheral and central nervous systems in controlling tumorigenesis and metastasis has opened a new area of research to identify innovative approaches against cancer. Although the 'neural addiction' of cancer is only partially understood, in this Perspective we discuss the current knowledge and perspectives on peripheral and central nerve circuitries and brain areas that can support tumorigenesis and metastasis and the possible reciprocal influence that the brain and peripheral tumours exert on one another. Tumours can build up local autonomic and sensory nerve networks and are able to develop a long-distance relationship with the brain through circulating adipokines, inflammatory cytokines, neurotrophic factors or afferent nerve inputs, to promote cancer initiation, growth and dissemination. In turn, the central nervous system can affect tumour development and metastasis through the activation or dysregulation of specific central neural areas or circuits, as well as neuroendocrine, neuroimmune or neurovascular systems. Studying neural circuitries in the brain and tumours, as well as understanding how the brain communicates with the tumour or how intratumour nerves interplay with the tumour microenvironment, can reveal unrecognized mechanisms that promote cancer development and progression and open up opportunities for the development of novel therapeutic strategies. Targeting the dysregulated peripheral and central nervous systems might represent a novel strategy for next-generation cancer treatment that could, in part, be achieved through the repurposing of neuropsychiatric drugs in oncology.

Beta Blockers with Statins May Decrease All-Cause Mortality in Patients with Cardiovascular Diseases and Locally Advanced Unresectable Non-Small-Cell Lung Cancer after Chemoradiotherapy

The study was conducted in the era when maintenance immunotherapy with durvalumab was not available in clinical practice after chemoradiotherapy (CRT) in unresectable non-small-cell lung cancer (NSCLC). The main aim of the study was to check whether the presence of cardiovascular diseases (CVD) and their pharmacotherapy affects the overall survival (OS) in such NSCLC patients undergoing sequential CRT. The group of 196 patients were analyzed: 101 patients with CVD (51.53%) and 95 patients with other reasons of qualification for sequential CRT (decreased performance status, older age, and other non-cardiovascular co-morbidities). Although patients with CVD were more often in older age, and they more often experienced cardiac and nephrological complications (p < 0.05 for all), there was a statistically nonsignificant trend for lower all-cause mortality in patients with CVD. The lowest all-cause mortality was observed in patients treated with beta-blockers and statins after two (HR = 0.31; 95%CI: 0.1-0.98; p = 0.047), three (HR = 0.33; 95%CI: 0.13-0.81; p = 0.015) and even four (HR = 0.45; 95%CI: 0.22-0.97; p = 0.027) years of follow-up. The benefit in OS remained significant in 101 patients with CVD treated with beta-blockers (HR = 0.65; 95%CI: 0.43-0.99; p = 0.045), and eventually statin, throughout the whole follow-up (log-rank p < 0.05). Further prospective studies are necessary to confirm the role of beta-blockers and statins in reduction of mortality in NSCLC patients undergoing radical CRT.

Propranolol reduces IFN-γ driven PD-L1 immunosuppression and improves anti-tumour immunity in ovarian cancer

The immune system plays an important role in controlling epithelial ovarian cancer (EOC). EOC is considered to be a "cold tumour," a tumour that has not triggered a strong response by the immune system. However, tumour infiltrating lymphocytes (TILs) and the expression of programmed cell death ligand (PD-L1) are used as prognostic indicators in EOC. Immunotherapy such as PD-(L)1 inhibitors have shown limited benefit in EOC. Since the immune system is affected by behavioural stress and the beta-adrenergic signalling pathway, this study aimed to explore the impact of propranolol (PRO), a beta-blocker, on anti-tumour immunity in both in vitro and in vivo EOC models. Noradrenaline (NA), an adrenergic agonist, did not directly regulate PD-L1 expression but PD-L1 was significantly upregulated by IFN-γ in EOC cell lines. IFN-γ also increased PD-L1 on extracellular vesicles (EVs) released by ID8 cells. PRO significantly decreased IFN-γ levels in primary immune cells activated ex vivo and showed increased viability of the CD8⁺ cell population in an EV-immune cell co-incubation. In addition, PRO reverted PD-L1 upregulation and significantly decreased IL-10 levels in an immune-cancer cell co-culture. Chronic behavioural stress increased metastasis in mice while PRO monotherapy and the combo of PRO and PD-(L)1 inhibitor significantly decreased stress-induced metastasis. The combined therapy also reduced tumour weight compared to the cancer control group and induced anti-tumour T-cell responses with significant CD8 expression in tumour tissues. In conclusion, PRO showed a modulation of the cancer immune response by decreasing IFN-γ production and, in turn, IFN-γ-mediated PD-L1 overexpression. The combined therapy of PRO and PD-(L)1 inhibitor decreased metastasis and improved anti-tumour immunity offering a promising new therapy.

Chronic stress in solid tumor development: from mechanisms to interventions

Chronic stress results in disturbances of body hormones through the neuroendocrine system. Cancer patients often experience recurrent anxiety and restlessness during disease progression and treatment, which aggravates disease progression and hinders treatment effects. Recent studies have shown that chronic stress-regulated neuroendocrine systems secret hormones to activate many signaling pathways related to tumor development in tumor cells. The activated neuroendocrine system acts not only on tumor cells but also modulates the survival and metabolic changes of surrounding non-cancerous cells. Current clinical evidences also suggest that chronic stress affects the outcome of cancer treatment. However, in clinic, there is lack of effective treatment for chronic stress in cancer patients. In this review, we discuss the main mechanisms by which chronic stress regulates the tumor microenvironment, including functional regulation of tumor cells by stress hormones (stem cell-like properties, metastasis, angiogenesis, DNA damage accumulation, and apoptotic resistance), metabolic reprogramming and immune escape, and peritumor neuromodulation. Based on the current clinical treatment framework for cancer and chronic stress, we also summarize pharmacological and non-pharmacological therapeutic approaches to provide some directions for cancer therapy.

The β-Blocker Carvedilol Prevents Benzo(a)pyrene-Induced Lung Toxicity, Inflammation and Carcinogenesis

The current study evaluated the effects of the β-blocker carvedilol on benzo(a)pyrene (B(a)P) and its active metabolite benzo(a)pyrene diol epoxide (BPDE)-induced lung toxicity, inflammation and carcinogenesis and explored the potential mechanisms. Carvedilol blocked the BPDE-induced malignant transformation of human bronchial epithelial cells BEAS-2B. In BEAS-2B cells, B(a)P strongly activated ELK-1, a transcription factor regulating serum response element (SRE) signaling, which was attenuated by carvedilol. Carvedilol also inhibited the B(a)P-induced AhR/xenobiotic responsive element (XRE) and mRNA expression of CYP1A1 and attenuated B(a)P-induced NF-κB activation. In a B(a)P-induced acute lung toxicity model in CD-1/IGS mice, pretreatment with carvedilol for 7 days before B(a)P exposure effectively inhibited the B(a)P-induced plasma levels of lactate dehydrogenase and malondialdehyde, inflammatory cell infiltration and histopathologic abnormalities in the lung, and upregulated the expression of GADD45α, caspase-3 and COX-2 in the lung. In a B(a)P-induced lung carcinogenesis model in A/J mice, carvedilol treatment for 20 weeks did not affect body weight but significantly attenuated tumor multiplicity and volume. These data reveal a previously unexplored role of carvedilol in preventing B(a)P-induced lung inflammation and carcinogenesis by inhibiting the cross-talk of the oncogenic transcription factors ELK-1, AhR and NF-κB.

Countermeasures for Maintaining Cardiovascular Health in Space Missions

During space exploration, the human body is subjected to altered atmospheric environments and gravity, exposure to radiation, sleep disturbance, and mental pressures; all these factors are responsible for cardiovascular diseases. Under microgravity, the physiological changes related to cardiovascular diseases are the cephalic fluid shift, dramatic reduction in central venous pressure, changes in blood rheology and endothelial function, cerebrovascular abnormalities, headaches, optic disc edema, intracranial hypertension, congestion of the jugular vein, facial swelling, and loss of taste. Generally, five countermeasures are used to maintain cardiovascular health (during and after space missions), including shielding, nutritional, medicinal, exercise, and artificial gravity. This article concludes with how to reduce space missions' impact on cardiovascular health with the help of various countermeasures.

Dual effect of radiotherapy related concomitant cardiovascular diseases in non-small cell lung cancer

BACKGROUND

Nowadays, cancer and cardiac diseases are two of the most causes of death, so cancer treatment-related cardiac death cannot be ignored. For lung cancer, chest radiotherapy (RT) is essential, but the related cardiotoxicity has not been fully studied.

METHODS

We reviewed the data of 11,455 patients with non-small cell lung cancer (NSCLC) from the Surveillance, Epidemiology, and End Results database from 2001 to 2015. The change trend for concomitant cardiovascular diseases (CVD)-specific death was calculated and graphically demonstrated. Univariate and multivariate analyses for survival were performed using Cox risk regression model.

RESULTS

In our analysis, the overall incidence and mortality from NSCLC declined, but CVD-specific death increased. Both chemoradiotherapy and radiotherapy alone played a significant role in CVD-specific death. Analyzed longitudinally from diagnosis, we found that the effect of RT in CVD-specific death increased continuously over the third years and the hazard ratio for CVD-specific death was 1.386 times between RT and non-RT group (HR = 1.386, 95% CI 1.322-1.452; p < 0.0001). On the other hand, RT played a protective role in CVD-specific death before the second years, especially in recent years from 2013 to 2015 (HR = 0.843, 95% CI 0.740-0.959; p = 0.009).

CONCLUSIONS

Although the mortality from NSCLC decreased, but radiotherapy-related CVD-specific mortality cannot be ignored. In the long-term over 3 years, RT significantly promoted CVD-specific death. However, RT turned to be a protective role in the short-term within 2 years. In clinical practice, we need to comprehensively consider the dual effects of radiotherapy on the side effect of heart.

Association of heartbeat complexity with survival in advanced non-small cell lung cancer patients

Background

Previous studies have shown that the predictive value of traditional linear (time domain and frequency domain) heart rate variability (HRV) for the survival of patients with advanced non-small cell lung cancer (NSCLC) is controversial. Nonlinear methods, based on the concept of complexity, have been used to evaluate HRV, providing a new means to reveal the physiological and pathological changes in HRV. This study aimed to assess the association between heartbeat complexity and overall survival in patients with advanced NSCLC.

Methods

This study included 78 patients with advanced NSCLC (mean age: 62.0 ± 9.3 years). A 5-min resting electrocardiogram of advanced NSCLC patients was collected to analyze the following HRV parameters: time domain indicators, i.e., standard deviation of the normal-normal intervals (SDNN) and root mean square of successive interval differences (RMSSD); frequency domain indicators, i.e., total power (TP), low frequency power (LF), high frequency power (HF), and the ratio of LF to HF (LF/HF); nonlinear HRV indicators characterizing heartbeat complexity, i.e., approximate entropy (ApEn), sample entropy (SampEn), and recurrence quantification analysis (RQA) indexes: mean diagonal line length (Lmean), maximal diagonal line length (Lmax), recurrence rate (REC), determinism (DET), and shannon entropy (ShanEn).

Results

Univariate analysis revealed that the linear frequency domain parameter HF and nonlinear RQA parameters Lmax, REC, and DET were significantly correlated with the survival of advanced NSCLC patients (all p < 0.05). After adjusting for confounders in the multivariate analysis, HF, REC, and DET were found to be independent prognostic factors for the survival of patients with advanced NSCLC (all p < 0.05).

Conclusion

There was an independent association between heartbeat complexity and survival in advanced NSCLC patients. The nonlinear analysis method based on RQA may provide valuable additional information for the prognostic stratification of patients with advanced NSCLC and may supplement the traditional time domain and frequency domain analysis methods.

Beta-blockers disrupt mitochondrial bioenergetics and increase radiotherapy efficacy independently of beta-adrenergic receptors in medulloblastoma

Background

Medulloblastoma is the most frequent brain malignancy of childhood. The current multimodal treatment comes at the expense of serious and often long-lasting side effects. Drug repurposing is a strategy to fast-track anti-cancer therapy with low toxicity. Here, we showed the ability of β-blockers to potentiate radiotherapy in medulloblastoma with bad prognosis.

Methods

Medulloblastoma cell lines, patient-derived xenograft cells, 3D spheroids and an innovative cerebellar organotypic model were used to identify synergistic interactions between β-blockers and ionising radiations. Gene expression profiles of β-adrenergic receptors were analysed in medulloblastoma samples from 240 patients. Signaling pathways were explored by RT-qPCR, RNA interference, western blotting and RNA sequencing. Medulloblastoma cell bioenergetics were evaluated by measuring the oxygen consumption rate, the extracellular acidification rate and superoxide production.

Findings

Low concentrations of β-blockers significantly potentiated clinically relevant radiation protocols. Although patient biopsies showed detectable expression of β-adrenergic receptors, the ability of the repurposed drugs to potentiate ionising radiations did not result from the inhibition of the canonical signaling pathway. We highlighted that the efficacy of the combinatorial treatment relied on a metabolic catastrophe that deprives medulloblastoma cells of their adaptive bioenergetics capacities. This led to an overproduction of superoxide radicals and ultimately to an increase in ionising radiations-mediated DNA damages.

Interpretation

These data provide the evidence of the efficacy of β-blockers as potentiators of radiotherapy in medulloblastoma, which may help improve the treatment and quality of life of children with high-risk brain tumours.

Funding

This study was funded by institutional grants and charities.

Beta-adrenergic receptor blockers and hepatocellular carcinoma survival: a systemic review and meta-analysis

INTRODUCTION

Preclinical data have revealed that beta-adrenergic stimulation can affect the growth and progression of different types of malignancies. Beta-adrenergic receptor blockers have been associated with improved survival in patients with many types of cancer. We performed a meta-analysis to investigate the association between beta-blocker use and hepatocellular carcinoma (HCC) prognosis.

METHODS

In this meta-analysis, a full search was conducted using PubMed, the Cochrane library and Embase to identify all relevant studies published up to May 2021. Available hazard ratios (HRs) were extracted for overall survival (OS), cancer-specific survival (CSS) and pooled using a random-effects meta-analysis.

RESULTS

Four studies involving 7252 patients with HCC met the inclusion criteria and were included in the systemic review. Three studies that reported OS data of 5148 patients were included in the meta-analysis. The random-effects model showed that beta-blocker use was associated with significantly improved OS in HCC (HR = 0.69, 95% CI = 0.54-0.88, P = 0.0031), without significant heterogeneity (I² = 41%; Q = 6.42, P = 0.18).

CONCLUSION

This meta-analysis suggested that beta-blocker use can be associated with prolonged OS of patients with HCC.

Development and Validation of a Risk Prediction Model for Breast Cancer Prognosis Based on Depression-Related Genes

Background

Depression plays a significant role in mediating breast cancer recurrence and metastasis. However, a precise risk model is lacking to evaluate the potential impact of depression on breast cancer prognosis. In this study, we established a depression-related gene (DRG) signature that can predict overall survival (OS) and elucidate its correlation with pathological parameters and sensitivity to therapy in breast cancer.

Methods

The model training and validation assays were based on the analyses of 1,096 patients from The Cancer Genome Atlas (TCGA) database and 2,969 patients from GSE96058. A risk signature was established through univariate and multivariate Cox regression analyses.

Results

Ten DRGs were determined to construct the risk signature. Multivariate analysis revealed that the signature was an independent prognostic factor for OS. Receiver operating characteristic (ROC) curves indicated good performance of the model in predicting 1-, 3-, and 5-year OS, particularly for patients with triple-negative breast cancer (TNBC). In the high-risk group, the proportion of immunosuppressive cells, including M0 macrophages, M2 macrophages, and neutrophils, was higher than that in the low-risk group. Furthermore, low-risk patients responded better to chemotherapy and endocrine therapy. Finally, a nomogram integrating risk score, age, tumor-node-metastasis (TNM) stage, and molecular subtypes were established, and it showed good agreement between the predicted and observed OS.

Conclusion

The 10-gene risk model not only highlights the significance of depression in breast cancer prognosis but also provides a novel gene-testing tool to better prevent the potential adverse impact of depression on breast cancer prognosis.

Pan-Cancer Characterization of Intratumoral Autonomic Innervation in 32 Cancer Types in the Cancer Genome Atlas

Simple Summary

There have been growing interests in the roles of intratumoral innervation of the autonomic nervous system (ANS) as a mechanism linking psychosocial stress, β-adrenergic signaling pathways, and poor cancer outcomes, and a potential target for therapeutic purpose. Our current knowledge is being limited by the few cancer types where intratumoral ANS have been studied; it remains to be determined the extent of this mechanism existing in different cancer types. Our study provided the first pan-cancer characterization of intratumoral innervation across 32 cancer types, and further, their relationships with tumor histopathological and molecular characteristics and survival outcomes. We found wide variations in intratumoral ANS expression both within and across cancer types. The association of ANS signatures with tumor histopathological characteristics and survival outcomes also varied by cancer type. Our findings suggest that the potential benefits of cancer therapies targeting β-adrenergic receptor-mediated stress signaling pathways are likely dependent on cancer type.

Abstract

Over the past two decades, multiple studies have demonstrated the important role that the autonomic nervous system (ANS) plays in tumorigenesis and cancer progression. However, the mechanisms by which this process occurs have only recently begun to be elucidated. Further, the extent of autonomic innervation in various cancer types and its effects on tumor molecular, immunological, and histopathological features, as well as on patient outcomes, are not yet fully characterized. In this study, we analyzed intratumoral ANS gene expression signatures, including overall intratumoral neuron growth and sympathetic and parasympathetic markers, across 32 cancer types using tumor transcriptomic and clinical annotation data available from The Cancer Genome Atlas (TCGA). Our analysis revealed wide variations in intratumoral ANS expression both within and across cancer types. The association of ANS signatures with tumor histopathological characteristics and survival outcomes also varied by cancer type. We found intratumoral ANS expression to be commonly correlated with angiogenesis, TGF-β signaling, and immunosuppression in the tumor microenvironment of many cancer types, which provide mechanistic insights into the involvement of intratumoral innervation in cancer development and progression. Our findings suggest that the potential benefits of cancer therapies targeting β-adrenergic receptor-mediated stress signaling pathways are likely dependent on cancer type.

Targeting tumor innervation: premises, promises, and challenges

A high intratumoral nerve density is correlated with poor survival, high metastasis, and high recurrence across multiple solid tumor types. Recent research has revealed that cancer cells release diverse neurotrophic factors and exosomes to promote tumor innervation, in addition, infiltrating nerves can also mediate multiple tumor biological processes via exosomes and neurotransmitters. In this review, through seminal studies establishing tumor innervation, we discuss the communication between peripheral nerves and tumor cells in the tumor microenvironment (TME), and revealed the nerve-tumor regulation mechanisms on oncogenic process, angiogenesis, lymphangiogenesis, and immunity. Finally, we discussed the promising directions of ‘old drugs newly used’ to target TME communication and clarified a new line to prevent tumor malignant capacity.

The Effect of Beta Adrenoreceptor Blockers on Viability and Cell Colony Formation of Non-Small Cell Lung Cancer Cell Lines A549 and H1299

Beta adrenoblockers are a large class of drugs used to treat cardiovascular diseases, migraines, glaucoma and hyperthyroidism. Over the last couple of decades, the anticancer effects of these compounds have been extensively studied. However, the exact mechanism is still not known, and more detailed studies are required. The aim of our study was to evaluate the anticancer activity of beta adrenoblockers in non-small cell lung cancer cell lines A549 and H1299. In order to find the relationship with their selectivity to beta adrenoreceptors, selective (atenolol, betaxolol, esmolol, metoprolol) and non-selective (pindolol, propranolol and timolol) beta blockers were tested. The effect on cell viability was evaluated by MTT assay, and the activity on cell ability to form colonies was tested by clonogenic assay. The type of cell death was evaluated by cell double staining with Hoechst 33342 and Propidium iodide. The most active adrenoblockers against both tested cancer cell lines were propranolol and betaxolol. They completely inhibited lung cancer cell colony formation at 90% of the EC₅₀ (half-maximal effective concentration) value. Most tested compounds induced cell death through apoptosis and necrosis. There was no correlation established between beta adrenoblocker anticancer activity and their selectivity to beta adrenoreceptors.

Chronic Stress Effects on Tumor: Pathway and Mechanism

Chronic stress is an emotional experience that occurs when people encounter something they cannot adapt to. Repeated chronic stress increases the risk of a variety of diseases, such as cardiovascular disease, depression, endocrine disease, inflammation and cancer. A growing body of research has shown that there is a link between chronic stress and tumor occurrence in both animal studies and clinical studies. Chronic stress activates the neuroendocrine system (hypothalamic-pituitary-adrenal axis) and sympathetic nervous system. Stress hormones promote the occurrence and development of tumors through various mechanisms. In addition, chronic stress also affects the immune function of the body, leading to the decline of immune monitoring ability and promote the occurrence of tumors. The mechanisms of chronic stress leading to tumor include inflammation, autophagy and epigenetics. These factors increase the proliferation and invasion capacity of tumor cells and alter the tumor microenvironment. Antagonists targeting adrenergic receptors have played a beneficial role in improving antitumor activity, as well as chemotherapy resistance and radiation resistance. Here, we review how these mechanisms contribute to tumor initiation and progression, and discuss whether these molecular mechanisms might be an ideal target to treat tumor.

Biobehavioral Pathways and Cancer Progression: Insights for Improving Well-Being and Cancer Outcomes

The relationship between psychosocial factors and cancer has intrigued people for centuries. In the last several decades there has been an expansion of mechanistic research that has revealed insights regarding how stress activates neuroendocrine stress-response systems to impact cancer progression. Here, we review emerging mechanistic findings on key pathways implicated in the effect of stress on cancer progression, including the cellular immune response, inflammation, angiogenesis, and metastasis, with a primary focus on the mediating role of the sympathetic nervous system. We discuss converging findings from preclinical and clinical cancer research that describe these pathways and research that reveals how these stress pathways may be targeted via pharmacological and mind-body based interventions. While further research is required, the body of work reviewed here highlights the need for and feasibility of an integrated approach to target stress pathways in cancer patients to achieve comprehensive cancer treatment.

Stress and cancer: mechanisms, significance and future directions

The notion that stress and cancer are interlinked has dominated lay discourse for decades. More recent animal studies indicate that stress can substantially facilitate cancer progression through modulating most hallmarks of cancer, and molecular and systemic mechanisms mediating these effects have been elucidated. However, available clinical evidence for such deleterious effects is inconsistent, as epidemiological and stress-reducing clinical interventions have yielded mixed effects on cancer mortality. In this Review, we describe and discuss specific mediating mechanisms identified by preclinical research, and parallel clinical findings. We explain the discrepancy between preclinical and clinical outcomes, through pointing to experimental strengths leveraged by animal studies and through discussing methodological and conceptual obstacles that prevent clinical studies from reflecting the impacts of stress. We suggest approaches to circumvent such obstacles, based on targeting critical phases of cancer progression that are more likely to be stress-sensitive; pharmacologically limiting adrenergic-inflammatory responses triggered by medical procedures; and focusing on more vulnerable populations, employing personalized pharmacological and psychosocial approaches. Recent clinical trials support our hypothesis that psychological and/or pharmacological inhibition of excess adrenergic and/or inflammatory stress signalling, especially alongside cancer treatments, could save lives.

The Sympathetic Nervous System Modulates Cancer Vaccine Activity through Monocyte-Derived Cells

The sympathetic nervous system (SNS) is an important regulator of immune cell function during homeostasis and states of inflammation. Recently, the SNS has been found to bolster tumor growth and impair the development of antitumor immunity. However, it is unclear whether the SNS can modulate APC function. Here, we investigated the effects of SNS signaling in murine monocyte-derived macrophages (moMФ) and dendritic cells (DCs) and further combined the nonspecific β-blocker propranolol with a peptide cancer vaccine for the treatment of melanoma in mice. We report that norepinephrine treatment dramatically altered moMФ cytokine production, whereas DCs were unresponsive to norepinephrine and critically lack β₂-adrenergic receptor expression. In addition, we show that propranolol plus cancer vaccine enhanced peripheral DC maturation, increased the intratumor proportion of effector CD8⁺ T cells, and decreased the presence of intratumor PD-L1⁺ myeloid-derived suppressor cells. Furthermore, this combination dramatically reduced tumor growth compared with vaccination alone. Taken together, these results offer insights into the cell-specific manner by which the SNS regulates the APC immune compartment and provide strong support for the use of propranolol in combination with cancer vaccines to improve patient response rates and survival.

The impact of beta-blocker use at the time of hematopoietic cell transplantation on the development of acute and chronic graft-versus-host disease

Sympathetic nervous system activation plays a role in the development of acute and chronic graft-versus-host disease (GVHD) following allogeneic hematopoietic cell transplantation (HCT). The primary objective was to compare the cause-specific hazard of grade II-IV and III-IV acute GVHD (aGVHD) and chronic GVHD (cGVHD) in the context of ß-blocker use and type (selective vs. non-selective). Secondary objectives included overall survival (OS), relapse-free survival (RFS), and cumulative incidence of relapse, non-relapse mortality (NRM), and grade II-IV and III-IV aGVHD and cGVHD. The current study included 151 patients ages 18 and older diagnosed with hematological malignancies who underwent reduced intensity conditioning allogeneic HCT from HLA matched related or unrelated donors between January 2014 and 2017. 31 patients were on a ß-blocker of which 71% were on a selective ß-blocker. The incidence of aGVHD was not different among groups. Results show a non-significant trend in the association between ß-blocker use and reduction in the risk of developing cGVHD (cause-specific hazard ratio 0.49, p = 0.060), with no negative impact on survival or relapse. The current data are supportive of a potential ß-adrenergic influence on the pathogenesis of GVHD, consistent with the inflammatory etiology of GVHD and the anti-inflammatory effects of ß-adrenergic antagonists.

The Adrenergic Nerve Network in Cancer

The central and autonomic nervous systems interact and converge to build up an adrenergic nerve network capable of promoting cancer. While a local adrenergic sympathetic innervation in peripheral solid tumors influences cancer and stromal cell behavior, the brain can participate to the development of cancer through an intermixed dysregulation of the sympathoadrenal system, adrenergic neurons, and the hypothalamo-pituitary-adrenal axis. A deeper understanding of the adrenergic nerve circuitry within the brain and tumors and its interactions with the microenvironment should enable elucidation of original mechanisms of cancer and novel therapeutic strategies.

Impact of Concomitant Cardiovascular Medication on Survival of Metastatic Renal Cell Carcinoma Patients Treated with Sunitinib or Pazopanib in the First Line

BACKGROUND

Patients with metastatic renal cell carcinoma (mRCC) are often elderly and have various comorbidities, including cardiovascular diseases. Although these patients have extensive co-exposure to targeted therapy and cardiovascular drugs, the impact of this co-exposure on outcomes for patients with mRCC remains unclear.

OBJECTIVE

Our objective was to evaluate the association between the use of cardiovascular medication and survival of patients with mRCC.

METHODS

The study included 343 consecutive patients with mRCC treated with sunitinib or pazopanib in the first line. Clinical data obtained from the Renal Cell Carcinoma Information System (RENIS) clinical registry and hospital information systems were retrospectively analyzed. Progression-free survival (PFS) and overall survival (OS) were compared according to the use of common medications, including antihypertensives (i.e., β-blockers [BBs], angiotensin-converting enzyme inhibitors, angiotensin II receptor blockers, calcium channel blockers, and diuretics), acetylsalicylic acid (aspirin), statins, and proton pump inhibitors.

RESULTS

The univariate Cox analysis evaluating the impact of the assessed comedications on patient survival revealed that only BBs were significantly associated with PFS (hazard ratio [HR] 0.533, p < 0.001) and OS (HR 0.641, p = 0.006). The median PFS and OS for users of BBs was 18.39 and 37.60 months versus 8.16 and 20.4 months for patients not using BBs (p < 0.001 and p < 0.001, respectively). The Cox multivariate analysis showed that the use of BBs was a significant factor for both PFS (HR 0.428, p = 0.001) and OS (HR 0.518, p = 0.001).

CONCLUSIONS

The results of this retrospective study suggest that the use of BBs is associated with favorable outcomes for patients with mRCC treated with sunitinib or pazopanib in the first line.

Effect of beta-blockers on survival of lung cancer patients: a systematic review and meta-analysis

The recent interest in beta-blockers as possible agents for drug repurposing in oncology arises from many pre-clinical and epidemiologic studies suggesting a possible clinically relevant antitumour effect. In lung cancer, given the contradictory results obtained, it is crucial to further study its effects. A systematic review of the literature was planned to evaluate a possible beneficial effect of beta-blocker on overall survival in lung cancer patients. Medline and Embase databases were searched from inception until 1 May 2018 to identify published studies that assessed the effect beta-blocker use on overall survival in lung cancer patients. Risk of bias was evaluated by Newcastle-Ottawa scale. Hazard ratios and 95% confidence intervals for overall survival were estimated using a random-effects model. Of 920 studies, seven (all retrospective and observational, six cohort and one case-control), including 7448 patients, met the inclusion criteria. Beta-blocker users with lung cancer had no increased overall survival compared to non-users (hazard ratio = 1.00; 95% confidence interval = 0.91-1.10; I = 45%). Similarly, beta-blocker users with non-small cell lung cancer had no increased overall survival compared to beta-blocker non-users (hazard ratio = 0.96; 95% confidence interval = 0.80-1.17; I = 56%). Our findings do not suggest an overall survival advantage in patients with lung cancer using beta-blocker therapy when compared to non-users. Further prospective cohort studies, designed to overcome the intrinsic limitations of retrospective observational studies are warranted to definitively clarify any possible beneficial effect of beta-blockers on lung cancer overall survival.

Chronic propranolol treatment moderately attenuated development of N-methyl-N-nitrosourea-induced mammary carcinoma in female rats

The sympathetic nervous system participates in the development and progression of several cancer types and this effect is mediated mainly via β-adrenergic signaling. However, the potential of β-adrenergic signaling blockade to prevent cancer development after exposure to carcinogens has not been investigated, yet. Therefore, in our study, we determined the effect of the β-blocker propranolol on the development and progression of mammary cancer induced in female rats by administration of the chemical carcinogen N-methyl-N-nitrosourea (MNU). The propranolol treatment (20 mg/kg body weight) started 12 days after MNU administration and lasted 10 weeks. We found that both saline and propranolol treatment significantly increased gene expression of the catecholamine-synthesizing enzyme tyrosine hydroxylase, indicating that repeated injection of saline or propranolol-induced stress in these two groups. However, compared to the vehicle-treated group, propranolol slightly delayed the development and moderately reduced the incidence of mammary carcinoma in animals. To evaluate the mechanisms mediating the effect of propranolol on the development of MNU-induced cancer, we investigated several parameters of the tumor microenvironment and found that propranolol increased gene expression of Casp3. Our data indicate that propranolol treatment that starts after exposure to carcinogens might represent a new, useful approach for preventing the development of cancer, especially in stressed individuals. However, the potential efficiency of propranolol treatment for preventing cancer development and progression in individuals exposed to carcinogens needs further investigation.

Mechanisms Supporting the Use of Beta-Blockers for the Management of Breast Cancer Bone Metastasis

Simple Summary

Bone represents the most common site of metastasis for breast cancer and the establishment and growth of metastatic cancer cells within the skeleton significantly reduces the quality of life of patients and their survival. The interplay between sympathetic nerves and bone cells, and its influence on the process of breast cancer bone metastasis is increasingly being recognized. Several mechanisms, all dependent on β-adrenergic receptor signaling in stromal bone cells, were shown to promote the establishment of disseminated cancer cells into the skeleton. This review provides a summary of these mechanisms in support of the therapeutic potential of β-blockers for the early management of breast cancer metastasis.

Abstract

The skeleton is heavily innervated by sympathetic nerves and represents a common site for breast cancer metastases, the latter being the main cause of morbidity and mortality in breast cancer patients. Progression and recurrence of breast cancer, as well as decreased overall survival in breast cancer patients, are associated with chronic stress, a condition known to stimulate sympathetic nerve outflow. Preclinical studies have demonstrated that sympathetic stimulation of β-adrenergic receptors in osteoblasts increases bone vascular density, adhesion of metastatic cancer cells to blood vessels, and their colonization of the bone microenvironment, whereas β-blockade prevented these events in mice with high endogenous sympathetic activity. These findings in preclinical models, along with clinical data from breast cancer patients receiving β-blockers, support the pathophysiological role of excess sympathetic nervous system activity in the formation of bone metastases, and the potential of commonly used, safe, and low-cost β-blockers as adjuvant therapy to improve the prognosis of bone metastases.

Neurobiology of Cancer: Introduction of New Drugs in the Treatment and Prevention of Cancer

Research on the neurobiology of cancer, which lies at the border of neuroscience and oncology, has elucidated the mechanisms and pathways that enable the nervous system to modulate processes associated with cancer initiation and progression. This research has also shown that several drugs which modulate interactions between the nervous system and the tumor micro- and macroenvironments significantly reduced the progression of cancer in animal models. Encouraging results were also provided by prospective clinical trials investigating the effect of drugs that reduce adrenergic signaling on the course of cancer in oncological patients. Moreover, it has been shown that reducing adrenergic signaling might also reduce the incidence of cancer in animal models, as well as in humans. However, even if many experimental and clinical findings have confirmed the preventive and therapeutic potential of drugs that reduce the stimulatory effect of the nervous system on processes related to cancer initiation and progression, several questions remain unanswered. Therefore, the aim of this review is to critically evaluate the efficiency of these drugs and to discuss questions that need to be answered before their introduction into conventional cancer treatment and prevention.

Many Voices in a Choir: Tumor-Induced Neurogenesis and Neuronal Driven Alternative Splicing Sound Like Suspects in Tumor Growth and Dissemination

Simple Summary

Significant progress has recently been made in understanding the role of the neuronal system in cancer biology, in many solid tumors such as prostate, breast, pancreatic, gastric and brain cancers. Solid tumors and the nervous system appear to influence each other’s development both directly and indirectly. A recurring element in such interactions is constituted by nerve-related substances such as neurotransmitters and neurotrophins, to which the first part of the current review is devoted. The second part of the review focuses on the potential role played by alternative splicing in cancer progression associated with neural signaling. Alternative splicing is the process where pre-mRNA is cut and re-ligated in different ways to give rise to multiple protein isoforms whose expression profile is often cancer specific. Alternative splicing is known to take place in the mRNA of genes that code for proteins involved in neuronal development and the creation of new nerve fibers. The change in alternative splicing patterns that occur as tumors develop and progress may make these splice variants potential targets for the development of drug treatments. They may also serve as diagnostic or prognostic biomarkers.

Abstract

During development, as tissues expand and grow, they require circulatory, lymphatic, and nervous system expansion for proper function and support. Similarly, as tumors arise and develop, they also require the expansion of these systems to support them. While the contribution of blood and lymphatic systems to the development and progression of cancer is well known and is targeted with anticancer drugs, the contribution of the nervous system is less well studied and understood. Recent studies have shown that the interaction between neurons and a tumor are bilateral and promote metastasis on one hand, and the formation of new nerve structures (neoneurogenesis) on the other. Substances such as neurotransmitters and neurotrophins being the main actors in such interplay, it seems reasonable to expect that alternative splicing and the different populations of protein isoforms can affect tumor-derived neurogenesis. Here, we report the different, documented ways in which neurons contribute to the development and progression of cancer and investigate what is currently known regarding cancer-neuronal interaction in several specific cancer types. Furthermore, we discuss the incidence of alternative splicing that have been identified as playing a role in tumor-induced neoneurogenesis, cancer development and progression. Several examples of changes in alternative splicing that give rise to different isoforms in nerve tissue that support cancer progression, growth and development have also been investigated. Finally, we discuss the potential of our knowledge in alternative splicing to improve tumor diagnosis and treatment.

The role of ADRB2 gene polymorphisms in malignancies

Beta-2-adrenergic receptor is a member of the G protein-coupled receptor superfamily, which is highly expressed in most malignancies. There is increasing evidence showing that beta-2-adrenergic receptors are associated with carcinogenesis, proliferation, immune regulation, invasion, angiogenesis, clinical prognosis and treatment resistance in malignancies. Polymorphisms of the ADRB2 gene have been confirmed to be associated with transcriptional activity, mRNA translation, and beta-2-adrenergic receptor expression and sensitivity. This review discusses clinically relevant examples of single nucleotide polymorphisms of ADRB2 in malignancies and the effects of these polymorphisms on cancer susceptibility, prognosis and treatment response of cancer patients.

Control of immune cell trafficking through inter-organ communication

Cell migration is a cardinal feature of the immune system. Immune cell trafficking is orchestrated principally by chemokines and adhesion molecules, which guide the cells to the right place and at the right time to efficiently induce immune responses. Recent studies have demonstrated that signals from other organ systems influence the expression of and responsiveness to these guidance cues and consequentially immune cell migration. Neuronal inputs control entry and exit of immune cells to and from lymphoid and non-lymphoid tissues. The circadian clock helps establish diurnal variations in immune cell distribution among tissues. Nutritional status also alters immune cell homing to the bone marrow. In this review, we summarize the current knowledge about inter-organ control of immune cell trafficking and discuss the physiological and pathological significance of these mechanisms.

Concurrent β-blocker Use is Associated With Improved Outcome in Esophageal Cancer Patients Who Undergo Chemoradiation: A Retrospective Matched-pair Analysis

BACKGROUND

β-blocker use has been associated with improved outcomes in a number of different malignancies; however, the impact of β-blockade in esophageal cancer is not been well characterized. We compared the outcomes of esophageal cancer patients based on β-blocker usage.

METHODS

The charts of all 418 patients treated with radiation for esophageal cancer at our institution from April 2010 to October 2018 were analyzed. Patients who underwent treatment with palliative intent or did not finish treatment were excluded. β-blocker use was determined from the medication list at time of pretreatment consultation.

RESULTS

There were 291 esophageal cancer patients who received neoadjuvant/definitive chemoradiation therapy. The median follow-up for the cohort was 22.5 months (interquartile range: 9.6 to 41.0 mo). Within the cohort, 27.8% (n=81) of patients were taking β-blockers at the time of treatment. Those taking β-blockers had significantly improved distant control (22.2% vs. 37.9%; P=0.035). Concomitant β-blocker use was significantly associated with improved progression-free survival (P<0.001, hazard ratio=0.42 [0.27-0.66]) and overall survival (P=0.002, hazard ratio=0.55 [0.38-0.81]) on Cox regression analysis. Propensity score-matched pairs were created using tumor stage, nodal stage, sex, neoadjuvant versus definitive therapy, Karnofsky Performance Status, and aspirin use. This matched-pair analysis showed a significant progression-free survival (P=0.005) benefit in esophageal cancer patients taking β-blockers.

CONCLUSIONS

Concurrent β-blocker use is common within patients receiving concurrent chemoradiation for esophageal cancer. Esophageal cancer patients who received chemoradiation while taking β-blockers demonstrated significant benefits in survival-based outcomes.

Beta-blocker and survival in patients with lung cancer: A meta-analysis

Background

Beta-blocker (BB) is suggested to have anticancer efficacy. However, the potential influence of BB use on overall survival (OS) in patients with lung cancer remains undetermined. We aimed to evaluate the above relationship in an updated meta-analysis.

Methods

Observational studies comparing OS between users and non-users of BB with lung cancer were identified by search of PubMed, Embase, and Cochrane’s Library. A random-effect model was used to pool the results.

Results

Ten retrospective cohort studies with 30870 patients were included. Overall, BB use was not associated with significantly improved OS in lung cancer (hazard ratio [HR] = 1.02, 95% confidence interval [CI]: 0.98 to 1.06, p = 0.33) with moderate heterogeneity (I² = 29%). Stratified analyses showed similar results in patients with non-small cell lung cancer and small cell lung cancer, in studies with BB use before and after the diagnosis of lung cancer, and in studies with or without adjustment of smoking. Use of BB was associated with improved OS in patients with stage III lung cancer (HR = 0.91, 95% CI: 0.85 to 0.98, p = 0.02) and in patients that did not receive surgery resection (HR = 0.78, 95% CI: 0.64 to 0.96, p = 0.02), while use of non-selective BB was associated with worse OS (HR = 1.14, 95% CI: 1.01 to 1.28, p = 0.03).

Conclusions

This meta-analysis of retrospective cohort studies does not support a significant association between BB use and improved OS in lung cancer.

Highlighting the Potential for Chronic Stress to Minimize Therapeutic Responses to Radiotherapy through Increased Immunosuppression and Radiation Resistance

Ionizing radiation has been used in the treatment of cancer for more than 100 years. While often very effective, there is still a great effort in place to improve the efficacy of radiation therapy for controlling the progression and recurrence of tumors. Recent research has revealed the close interaction between nerves and tumor progression, especially nerves of the autonomic nervous system that are activated by a variety of stressful stimuli including anxiety, pain, sleep loss or depression, each of which is likely to be increased in cancer patients. A growing literature now points to a negative effect of chronic stressful stimuli in tumor progression. In this review article, we present data on the potential for adrenergic stress to influence the efficacy of radiation and in particular, its potential to influence the anti-tumor immune response, and the frequency of an "abscopal effect" or the shrinkage of tumors which are outside an irradiated field. We conclude that chronic stress can be a major impediment to more effective radiation therapy through mechanisms involving immunosuppression and increased resistance to radiation-induced tumor cell death. Overall, these data highlight the potential value of stress reduction strategies to improve the outcome of radiation therapy. At the same time, objective biomarkers that can accurately and objectively reflect the degree of stress in patients over prolonged periods of time, and whether it is influencing immunosuppression and radiation resistance, are also critically needed.

Interrupting Neuron-Tumor Interactions to Overcome Treatment Resistance

Neurons in the tumor microenvironment release neurotransmitters, neuroligins, chemokines, soluble growth factors, and membrane-bound growth factors that solid tumors leverage to drive their own survival and spread. Tumors express nerve-specific growth factors and microRNAs that support local neurons and guide neuronal growth into tumors. The development of feed-forward relationships between tumors and neurons allows tumors to use the perineural space as a sanctuary from therapy. Tumor denervation slows tumor growth in animal models, demonstrating the innervation dependence of growing tumors. Further in vitro and in vivo experiments have identified many of the secreted signaling molecules (e.g., acetylcholine, nerve growth factor) that are passed between neurons and cancer cells, as well as the major signaling pathways (e.g., MAPK/EGFR) involved in these trophic interactions. The molecules involved in these signaling pathways serve as potential biomarkers of disease. Additionally, new treatment strategies focus on using small molecules, receptor agonists, nerve-specific toxins, and surgical interventions to target tumors, neurons, and immune cells of the tumor microenvironment, thereby severing the interactions between tumors and surrounding neurons. This article discusses the mechanisms underlying the trophic relationships formed between neurons and tumors and explores the emerging therapies stemming from this work.

Phase I Clinical Trial of Combination Propranolol and Pembrolizumab in Locally Advanced and Metastatic Melanoma: Safety, Tolerability, and Preliminary Evidence of Antitumor Activity

PURPOSE

Increased β-adrenergic receptor (β-AR) signaling has been shown to promote the creation of an immunosuppressive tumor microenvironment (TME). Preclinical studies have shown that abrogation of this signaling pathway, particularly β2-AR, provides a more favorable TME that enhances the activity of anti-PD-1 checkpoint inhibitors. We hypothesize that blocking stress-related immunosuppressive pathways would improve tumor response to immune checkpoint inhibitors in patients. Here, we report the results of dose escalation of a nonselective β-blocker (propranolol) with pembrolizumab in patients with metastatic melanoma.

PATIENTS AND METHODS

A 3 + 3 dose escalation study for propranolol twice a day with pembrolizumab (200 mg every 3 weeks) was completed. The primary objective was to determine the recommended phase II dose (RP2D). Additional objectives included safety, antitumor activity, and biomarker analyses. Responders were defined as patients with complete or partial response per immune-modified RECIST at 6 months.

RESULTS

Nine patients with metastatic melanoma received increasing doses of propranolol in cohorts of 10, 20, and 30 mg twice a day. No dose-limiting toxicities were observed. Most common treatment-related adverse events (TRAEs) were rash, fatigue, and vitiligo, observed in 44% patients. One patient developed two grade ≥3 TRAEs. Objective response rate was 78%. While no significant changes in treatment-associated biomarkers were observed, an increase in IFNγ and a decrease in IL6 was noted in responders.

CONCLUSIONS

Combination of propranolol with pembrolizumab in treatment-naïve metastatic melanoma is safe and shows very promising activity. Propranolol 30 mg twice a day was selected as RP2D in addition to pembrolizumab based on safety, tolerability, and preliminary antitumor activity.

Effect of β-Blocker in Treatment-Naïve Patients With Advanced Lung Adenocarcinoma Receiving First-Generation EGFR-TKIs

Background

Through activation of adrenergic receptors, chronic stress can trigger the secretion of neurotransmitters and hormones that enhance tumor growth, increase angiogenesis, and promote drug resistance. This study aimed to evaluate the effect of β-blockers in patients receiving first-line epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) for lung adenocarcinoma.

Methods

This retrospective cohort study enrolled patients with advanced lung adenocarcinoma under first-line EGFR-TKIs between 2011 and 2014 in the National Health Insurance Research Database of Taiwan. The effects of β-blockers use, defined as ≥60 defined daily doses within 180 days before initiation of EGFR-TKI therapy, on the 2-year time-to-discontinuation (TTD) of EGFR-TKIs and 4-year overall survival (OS) were investigated using Cox regression analyses with inverse propensity score weighting and sensitivity analysis in subgroup with either hypertension or ischemic heart diseases.

Results

Among 4988 enrolled patients, 552 (11.1%) were in the β-blocker group. Patients in the β-blocker group were more likely to be older than 75 and had diabetes mellitus and cardiovascular comorbidities. In Cox regression analysis, β-blocker usage was associated with a longer TTD (hazard ratio, HR: 0.91 [0.86-0.96]) and OS (HR: 0.68 [0.64-0.72]). The results also favored β-blocker group in sensitivity analysis.

Conclusions

In treatment-naïve patients with advanced lung adenocarcinoma under first-line EGFR-TKIs, prior use of β-blocker was associated with a better outcome. The findings encourage further prospective clinical study to validate the possibility of β-blockers as adjuvant anticancer therapy.

The Impact of Beta Blockers on Survival Outcomes in Patients With Non-small-cell Lung Cancer Treated With Immune Checkpoint Inhibitors

BACKGROUND

Beta blockers have been associated with anti-tumorigenic effects, potentially by reducing adrenergic-mediated stress responses. Preclinical studies have additionally shown that beta blockade may enhance the efficacy of cancer immunotherapy. We investigated patients with lung cancer who concomitantly used beta blockers and immune checkpoint inhibitors (ICIs), with the hypothesis that beta blockade would positively impact clinical outcomes.

PATIENTS AND METHODS

We retrospectively reviewed the health records of 109 patients who were treated at Northwestern University from January 2014 through August 2018 with ICIs for non-small-cell lung cancer (NSCLC). Comparisons of overall survival and progression-free survival (PFS) were performed using Kaplan-Meier analysis with log-rank test, and a univariate regression analysis was performed with a Cox proportional hazards model.

RESULTS

Among 109 patients treated with ICIs for NSCLC, 28 of them were concomitantly prescribed beta blockers. Use of beta blockers was associated with increased PFS, with a hazard ratio of 0.58 and 95% confidence interval of 0.36 to 0.93. There was not a significant increase in overall survival among patients who took beta blockers (hazard ratio, 0.66; 95% confidence interval, 0.38-1.17). In a regression model, beta blockers were identified as predictive of PFS, as were non-squamous histology, tumor programmed death-ligand 1 positivity, and lower line of treatment.

CONCLUSIONS

Our data suggests beta blocker use may be associated with improved PFS among patients treated with ICIs for NSCLC. This was a small study, and these findings should be further validated in prospective clinical studies.

Stress and cancer. Part II: Therapeutic implications for oncology

Accumulated evidence has confirmed the ability of stress to promote the induction and progression of cancer (for review see Stress and cancer. Part I: Mechanisms mediating the effect of stressors on cancer). In support of this, data from clinical trials utilizing approaches that reduce stress-related signaling have shown prolonged survival of cancer patients. Therefore, the question has arisen as to how we can utilize this knowledge in the daily treatment of cancer patients. The main aim of this review is to critically analyze data from studies utilizing psychotherapy or treatment by β-blockers on the survival of cancer patients. Because these approaches, especially treatment by β-blockers, have been routinely used in clinical practice for decades in the treatment of non-cancer patients, their wider introduction into oncology might be realized in the near future.

Can stress promote the pathophysiology of brain metastases? A critical review of biobehavioral mechanisms

Chronic stress can promote tumor growth and progression through immunosuppressive effects and bi-directional interactions between tumor cells and their microenvironment. β-Adrenergic receptor signaling plays a critical role in mediating stress-related effects on tumor progression. Stress-related mechanisms that modulate the dissemination of tumor cells to the brain have received scant attention. Brain metastases are highly resistant to chemotherapy and contribute considerably to morbidity and mortality in various cancers, occurring in up to 20% of patients in some cancer types. Understanding the mechanisms promoting brain metastasis could help to identify interventions that improve disease outcomes. In this review, we discuss biobehavioral, sympathetic, neuroendocrine, and immunological mechanisms by which chronic stress can impact tumor progression and metastatic dissemination to the brain. The critical role of the inflammatory tumor microenvironment in tumor progression and metastatic dissemination to the brain, and its association with stress pathways are delineated. We also discuss translational implications for biobehavioral and pharmacological interventions.

Postoperative atrial fibrillation does not impact on overall survival after esophagectomy in patients with thoracic esophageal cancer: results from a randomized, double-blind, placebo-controlled trial

Background: Administration of landiolol hydrochloride was found to be associated with reduced incidence of atrial fibrillation (AF) after esophagectomy for esophageal cancer in our previous randomized controlled trial (RCT). In addition, reduced incidence of AF was associated with reduction of other complications. Meanwhile, the effects of postoperative AF and other complications on long-term survival following esophagectomy are not well understood.

Materials and Methods: Between March 2014 and January 2016, 100 patients with esophageal cancer were registered in an RCT trial and randomly allocated to receive either administration of landiolol or a placebo. We analyzed data from this RCT to better understand the effect of postoperative AF and severe associated complications on overall survival (OS) after esophagectomy for cancer. We also examined whether prophylactic administration of landiolol hydrochloride directly affects prolonged survival in patients with esophageal cancer.

Results: The five-year rates of OS in the patients with and without AF were 60%, and 68.6%, respectively, there was no significant difference (P = 0.328). Five-year rates of OS of the patients with and without severe complications were 64.6%, and 67.5%, respectively (P = 0.995). The five-year rates of OS in the placebo and landiolol groups were 65.8% and 68%, respectively (P = 0.809). In multivariate analysis, high stage (stage III/IV) alone was an independent prognostic factor for esophageal cancer patients following esophagectomy.

Conclusions: New-onset AF and the other severe complications were not associated with poorer long-term survival following esophagectomy. In addition, administration of landiolol hydrochloride after esophagectomy did not contribute to prolonging the OS.

The Autonomic Regulation of Tumor Growth and the Missing Links

Accumulating evidence now indicates that peripheral nerves and solid tumors mutually support the growth of each other. Tumor-derived molecular cues guide nerve infiltration to the tumor milieu, while the tumor-infiltrating nerves provide molecular support to promote tumor growth and dissemination. In this mini-review, we discuss the unique roles of sympathetic and parasympathetic nerves in promoting tumor growth and metastasis. The contribution of adrenergic and cholinergic signals, the specific receptors involved, and the downstream molecular links in both cancer cells and stromal cells are discussed for their intrinsic capacity to modulate tumor growth. We identified unappreciated niche areas in the field, an investigation of which are critical to filling the knowledge gap in understanding the biology of neuromodulation of cancers.

Adrenergic stress constrains the development of anti-tumor immunity and abscopal responses following local radiation

The abscopal effect following ionizing radiation therapy (RT) is considered to be a rare event. This effect does occur more frequently when combined with other therapies, including immunotherapy. Here we demonstrate that the frequency of abscopal events following RT alone is highly dependent upon the degree of adrenergic stress in the tumor-bearing host. Using a combination of physiologic, pharmacologic and genetic strategies, we observe improvements in the control of both irradiated and non-irradiated distant tumors, including metastatic tumors, when adrenergic stress or signaling through β-adrenergic receptor is reduced. Further, we observe cellular and molecular evidence of improved, antigen-specific, anti-tumor immune responses which also depend upon T cell egress from draining lymph nodes. These data suggest that blockade of β2 adrenergic stress signaling could be a useful, safe, and feasible strategy to improve efficacy in cancer patients undergoing radiation therapy.