Sympathetic signaling facilitates progression of neuroendocrine prostate cancer

Nervous system contributions to small cell lung cancer: Lessons from diverse oncological studies

The nervous system plays a vital role throughout the entire lifecycle and it may regulate the formation, development and metastasis of tumors. Small cell lung cancer is a typical neuroendocrine tumor, and it is naturally equipped with neurotropism. In this review, we firstly summarize current preclinical and clinical evidence to demonstrate the reciprocal crosstalk among the nervous system, tumor, and tumor microenvironment in various ways, including neurotransmitter-receptor pathways, innervations of nerve fibers, different types of synapse formation by neurons, astrocytes, and cancer cells, neoneurogenesis. Futherly, we emphasize how the nervous system interacts with small cell lung cancer and discuss the limitations of current research methods for examining the interactions. We propose that integrating neuroscience, development biology, and tumor biology can be a promising direction to provide new insights into development and metastasis of small cell lung cancer and raise some novel treatment strategies.

AxonFinder: Automated segmentation of tumor innervating neuronal fibers

Neurosignaling is increasingly recognized as a critical factor in cancer progression, where neuronal innervation of primary tumors contributes to the disease's advancement. This study focuses on segmenting individual axons within the prostate tumor microenvironment, which have been challenging to detect and analyze due to their irregular morphologies. We present a novel deep learning-based approach for the automated segmentation of axons, AxonFinder, leveraging a U-Net model with a ResNet-101 encoder, based on a multiplexed imaging approach. Utilizing a dataset of whole-slide images from low-, intermediate-, and high-risk prostate cancer patients, we manually annotated axons to train our model, achieving significant accuracy in detecting axonal structures that were previously hard to segment. Our method achieves high performance, with a validation F1-score of 94 % and IoU of 90.78 %. Besides, the morphometric analysis that shows strong alignment between manual annotations and automated segmentation with nerve length and tortuosity closely matching manual measurements. Furthermore, our analysis includes a comprehensive assessment of axon density and morphological features across different CAPRA-S prostate cancer risk categories revealing a significant decline in axon density correlating with higher CAPRA-S prostate cancer risk scores. Our paper suggests the potential utility of neuronal markers in the prognostic assessment of prostate cancer in aiding the pathologist's assessment of tumor sections and advancing our understanding of neurosignaling in the tumor microenvironment.

Association between beta-blocker atenolol use and prostate cancer upgrading in active surveillance

Objectives

The objective of this study is to investigate the association between the use of beta-adrenergic antagonist atenolol and risk of pathologic upgrade in patients on active surveillance, considering growing literature implicating adrenergic innervation with disease progression mediated through beta-adrenergic signalling.

Patients and Methods

Men with low-risk or favourable intermediate-risk prostate cancer who were placed on an active surveillance protocol between 2006 and 2020 across three diverse urban hospitals were included. Exposure was duration of atenolol use, and outcome was pathologic grade group upgrading (to GG ≥ 3) on final prostate biopsy. Cox proportional hazard regression models were used to determine the associations between atenolol use and risk of upgrading with time, on a per-examination basis.

Results

A total of 467 men with initial GG ≤ 2 were included. Postdiagnosis atenolol use was associated with a decreased risk of pathologic upgrade to GG ≥ 3 on final repeat biopsy (HR 0.81, 95% CI 0.39-0.98). Longer duration of postdiagnosis atenolol use (>2 years) and greater cumulative atenolol dose (>730 defined daily doses) were associated with a more pronounced decreased risk of upgrade to GG ≥ 3 (HR 0.41, 95% CI 0.05-0.88, and HR 0.32, 95% CI 0.15-0.99, respectively). Initiation of atenolol use prior to prostate cancer diagnosis had a slightly greater protective effect than drug initiation postdiagnosis (HR 0.79, 95% CI 0.43-0.98, and HR 0.83, 95% CI 0.30-0.99, respectively).

Conclusions

Beta-adrenergic blockade with atenolol use in men on active surveillance is associated with a reduced risk for clinically significant grade group pathologic upgrade.

AxonFinder: Automated segmentation of tumor innervating neuronal fibers

Neurosignaling is increasingly recognized as a critical factor in cancer progression, where neuronal innervation of primary tumors contributes to the disease's advancement. This study focuses on segmenting individual axons within the prostate tumor microenvironment, which have been challenging to detect and analyze due to their irregular morphologies. We present a novel deep learning-based approach for the automated segmentation of axons, AxonFinder, leveraging a U-Net model with a ResNet-101 encoder, based on a multiplexed imaging approach. Utilizing a dataset of whole-slide images from low-, intermediate-, and high-risk prostate cancer patients, we manually annotated axons to train our model, achieving significant accuracy in detecting axonal structures that were previously hard to segment. Our analysis includes a comprehensive assessment of axon density and morphological features across different CAPRA-S prostate cancer risk categories, providing insights into the correlation between tumor innervation and cancer progression. Our paper suggests the potential utility of neuronal markers in the prognostic assessment of prostate cancer in aiding the pathologist's assessment of tumor sections and advancing our understanding of neurosignaling in the tumor microenvironment.

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.

Inhibition of β2-adrenergic receptor regulates necroptosis in prostate cancer cell

As the malignant tumor with the highest incidence in male, prostate cancer poses a significant threat to the reproductive health of elderly men. Our previous studies have shown that promoting necroptosis of cancer cells can effectively inhibit cancer cell proliferation. This study includes lentivirus-mediated knockdown of β2AR which resulted in stable transfectants that exhibited an increased ability to form clones compared to that of the negative control group. In the protein and mRNA levels, necroptosis associated RIP and mixed lineage kinase domain-like (MLKL) were significantly higher in the treatment group than they were in the control group. Furthermore, cells treated with propranolol exhibited necrotic morphology as observed by transmission electron microscopy. The combination of β2AR suppression and necroptosis inhibitors resulted in a more potent suppression of cell proliferation compared to that observed in the control and negative control groups. Additionally, it elevated in the necrosis rate as determined by flow cytometry. Immunofluorescence staining revealed enhanced RIP and MLKL expression in the sh-β2AR group compared to levels in the negative control group. Co-immunoprecipitation experiments detected an interaction between β2AR and RIP. MLKL and RIPK3 levels were significantly higher in xenograft tumor sections from the sh-β2AR group compared to levels in the sh-NC group. To conclude, our research indicates the proliferation of PC-3 and DU-145 cprostate cancer cells can be suppressed by inhibiting β2AR, and this occurs through the RIP/MLKL-mediated pathway of necroptosis.

PAX6 promotes neuroendocrine phenotypes of prostate cancer via enhancing MET/STAT5A-mediated chromatin accessibility

BACKGROUND

Neuroendocrine prostate cancer (NEPC) is a lethal subset of prostate cancer which is characterized by neuroendocrine differentiation and loss of androgen receptor (AR) signaling. Growing evidence reveals that cell lineage plasticity is crucial in the failure of NEPC therapies. Although studies suggest the involvement of the neural transcription factor PAX6 in drug resistance, its specific role in NEPC remains unclear.

METHODS

The expression of PAX6 in NEPC was identified via bioinformatics and immunohistochemistry. CCK8 assay, colony formation assay, tumorsphere formation assay and apoptosis assay were used to illustrate the key role of PAX6 in the progression of in vitro. ChIP and Dual-luciferase reporter assays were conducted to confirm the binding sequences of AR in the promoter region of PAX6, as well as the binding sequences of PAX6 in the promoter regions of STAT5A and MET. For in vivo validation, the xenograft model representing NEPC subtype underwent pathological analysis to verify the significant role of PAX6 in disease progression. Complementary diagnoses were established through public clinical datasets and transcriptome sequencing of specific cell lines. ATAC-seq was used to detect the chromatin accessibility of specific cell lines.

RESULTS

PAX6 expression was significantly elevated in NEPC and negatively regulated by AR signaling. Activation of PAX6 in non-NEPC cells led to NE trans-differentiation, while knock-down of PAX6 in NEPC cells inhibited the development and progression of NEPC. Importantly, loss of AR resulted in an enhanced expression of PAX6, which reprogramed the lineage plasticity of prostate cancer cells to develop NE phenotypes through the MET/STAT5A signaling pathway. Through ATAC-seq, we found that a high expression level of PAX6 elicited enhanced chromatin accessibility, mainly through attenuation of H4K20me3, which typically causes chromatin silence in cancer cells.

CONCLUSION

This study reveals a novel neural transcription factor PAX6 could drive NEPC progression and suggest that it might serve as a potential therapeutic target for the management of NEPC.

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.

Crosstalk Between Peripheral Innervation and Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive lethal malignancy, characterized by late diagnosis, aggressive growth, and therapy resistance, leading to a poor overall prognosis. Emerging evidence shows that the peripheral nerve is an important non-tumor component in the tumor microenvironment that regulates tumor growth and immune escape. The crosstalk between the neuronal system and PDAC has become a hot research topic that may provide novel mechanisms underlying tumor progression and further uncover promising therapeutic targets. In this review, we highlight the mechanisms of perineural invasion and the role of various types of tumor innervation in the progression of PDAC, summarize the potential signaling pathways modulating the neuronal-cancer interaction, and discuss the current and future therapeutic possibilities for this condition.

Neuropeptide Y and its receptors in prostate cancer: associations with cancer invasiveness and perineural spread

PURPOSE

Neuropeptide Y (NPY) is a pleiotropic peptide, which is involved in many biological mechanisms important in regulation of cell growth and survival. The aim of this study was a comprehensive analysis of the NPY system in prostate pathology.

METHODS

The study was based on immunohistochemical analysis of NPY and its receptors, Y1R, Y2R and Y5R, in tissue samples from benign prostate (BP), primary prostate cancer (PCa) and PCa bone metastases. Tissue microarray (TMA) technique was employed, with analysis of multiple cores from each specimen. Intensity of the immunoreactivity and expression index (EI), as well as distribution of the immunostaining in neoplastic cells and stromal elements were evaluated. Perineural invasion (PNI) and extraprostatic extension (EPE) were areas of special interests. Moreover, a transwell migration assay on the LNCaP PCa cell line was used to assess the chemotactic properties of NPY.

RESULTS

Morphological analysis revealed homogeneous membrane and cytoplasmic pattern of NPY staining in cancer cells and its membrane localization with apical accentuation in BP glands. All elements of the NPY system were upregulated in pre-invasive prostate intraepithelial neoplasia, PCa and metastases. EI and staining intensity of NPY receptors were significantly higher in PCa then in BP with correlation between Y2R and Y5R. The strength of expression of the NPY system was further increased in the PNI and EPE areas. In bone metastases, Y1R and Y5R presented high expression scores.

CONCLUSION

The results of our study suggest that the NPY system is involved in PCa, starting from early stages of its development to disseminated states of the disease, and participates in the invasion of PCa into the auto and paracrine matter.

Surgical Stress and Cancer Progression: New Findings and Future Perspectives

PURPOSE OF REVIEW

The stress response to surgery is essential for maintaining homeostasis and exhibits anti-tumor effects; however, an ongoing and exaggerated stress response may have adverse clinical consequences and even promote cancer progression. This review will discuss the complex relationship between surgical stress and cancer progression.

RECENT FINDINGS

Surgical stress exhibits both anti-tumor and cancer-promoting effects by causing changes in the neuroendocrine, circulatory, and immune systems. Many studies have found that many mechanisms are involved in the process, and the corresponding targets could be applied for cancer therapy. Although surgical stress may have anti-tumor effects, it is necessary to inhibit an excessive stress response, mostly showing cancer-promoting effects.

Endocrine and paracrine characteristics of neuroendocrine prostate cancer

Prostate cancer is a common malignancy affecting men worldwide. While the vast majority of newly diagnosed prostate cancers are categorized as adenocarcinomas, a spectrum of uncommon tumor types occur including those with small cell and neuroendocrine cell features. Benign neuroendocrine cells exist in the normal prostate microenvironment, and these cells may give rise to primary neuroendocrine carcinomas. However, the more common development of neuroendocrine prostate cancer is observed after therapeutics designed to repress the signaling program regulated by the androgen receptor which is active in the majority of localized and metastatic adenocarcinomas. Neuroendocrine tumors are identified through immunohistochemical staining for common markers including chromogranin A/B, synaptophysin and neuron specific enolase (NSE). These markers are also common to neuroendocrine tumors that arise in other tissues and organs such as the gastrointestinal tract, pancreas, lung and skin. Notably, neuroendocrine prostate cancer shares biochemical features with nerve cells, particularly functions involving the secretion of a variety of peptides and proteins. These secreted factors have the potential to exert local paracrine effects, and distant endocrine effects that may modulate tumor progression, invasion, and resistance to therapy. This review discusses the spectrum of factors derived from neuroendocrine prostate cancers and their potential to influence the pathophysiology of localized and metastatic prostate cancer.