Neurobiology of cancer: Interactions between nervous, endocrine and immune systems as a base for monitoring and modulating the tumorigenesis by the brain

The Nervous System as a Regulator of Cancer Hallmarks: Insights into Therapeutic Implications

Simple Summary

The nervous system communicates with the whole organism, regulating several physiological pathways. The modification of nerve activity could deregulate the state of cellular and tissue homeostasis which could drive cancer development. This paper provides the current state of knowledge, in an evidence-oriented manner, that the nervous system is able to participate in the carcinogenesis process by inducing biochemical, physiological, and cellular modifications involved in the hallmarks of cancer.

Abstract

The involvement of the nervous system in the development of cancer is controversial. Several authors have shown opinions and conflicting evidence that support the early effect of the nervous system on the carcinogenic process. For about a century, research has not been enough, questions remain open, ideas are not discarded, and although more research is still needed to answer all the questions, there is now enough evidence to support the theories and give hope of finding one more possible form of treatment. It is clear that malignant neoplasms have endogenous characteristics that allow them to establish and progress. Some of these characteristics known as hallmarks of cancer, are damage mechanisms in the pathology but necessary during other physiological processes which show some nerve dependence. The nervous system communicates with the whole organism, regulating physiological processes necessary to respond to external stimuli and for the maintenance of homeostasis. The modification of nerve activity could generate an overload and deregulate the state of cellular and tissue homeostasis; this could drive cancer development. In this review, we will address the issue in an evidence-oriented manner that supports that the nervous system is able to participate in the initial and progressive process of carcinogenesis by inducing biochemical, physiological, and cellular modifications involved in the hallmarks of cancer.

Pattern recognition receptors in health and diseases

Pattern recognition receptors (PRRs) are a class of receptors that can directly recognize the specific molecular structures on the surface of pathogens, apoptotic host cells, and damaged senescent cells. PRRs bridge nonspecific immunity and specific immunity. Through the recognition and binding of ligands, PRRs can produce nonspecific anti-infection, antitumor, and other immunoprotective effects. Most PRRs in the innate immune system of vertebrates can be classified into the following five types based on protein domain homology: Toll-like receptors (TLRs), nucleotide oligomerization domain (NOD)-like receptors (NLRs), retinoic acid-inducible gene-I (RIG-I)-like receptors (RLRs), C-type lectin receptors (CLRs), and absent in melanoma-2 (AIM2)-like receptors (ALRs). PRRs are basically composed of ligand recognition domains, intermediate domains, and effector domains. PRRs recognize and bind their respective ligands and recruit adaptor molecules with the same structure through their effector domains, initiating downstream signaling pathways to exert effects. In recent years, the increased researches on the recognition and binding of PRRs and their ligands have greatly promoted the understanding of different PRRs signaling pathways and provided ideas for the treatment of immune-related diseases and even tumors. This review describes in detail the history, the structural characteristics, ligand recognition mechanism, the signaling pathway, the related disease, new drugs in clinical trials and clinical therapy of different types of PRRs, and discusses the significance of the research on pattern recognition mechanism for the treatment of PRR-related diseases.

Serum gonadotropins, cortisol, PSA, and micronutrient levels among men with prostate carcinoma

Background

Prostate cancer (PrCa) is a malignant tumour of the prostate that has many associated risk factors. There is continuous rise in the incidence among adult blacks which is a reflection of racial differences in testosterone concentrations.

Methods

The study involves 50 PrCa patients attending or referred to two tertiary health Institutions and 25 healthy men as controls. Weight and height of participants were measured, and body mass index (BMI) was calculated. Ten millilitres of venous blood sample was collected from each participant, allowed to clot, and then centrifuged at 5000 rpm for 5 min at room temperature (22–28 °C) to obtain the serum. Serum cortisol, testosterone, follicle-stimulating hormone (FSH), luteinizing hormone (LH), total prostate-specific antigen (TPSA), free prostate-specific antigen (FPSA), selenium, copper, magnesium, and zinc were determined. Prostate ultrasonography and biopsy were also done for histopathological studies.

Result

From this study, a significant increase (p < 0.05) in weight, BMI, serum FPSA, TPSA, and copper; a non-significant increase (p > 0.05) in serum cortisol, testosterone; a significant decrease (p < 0.05) in serum LH, selenium, zinc, and magnesium; and a non-significant decrease (p > 0.05) in serum FSH were observed among people living with PrCa when compared to the controls. However, no significant difference (p > 0.05) was observed in the height between the two groups. Ultrasonography and histology revealed evidence of prostatitis, hypertrophy, and carcinoma among the test group.

Conclusion

It can be concluded that PrCa is associated with increase serum cortisol, testosterone, and copper; and decreased serum LH, FSH, selenium, zinc, and magnesium concentrations and combination of biochemical, ultrasonographic, and histologic features are of diagnostic importance.

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.

Neuroimmune Regulation of Surgery-Associated Metastases

Surgery remains an essential therapeutic approach for most solid malignancies. Although for more than a century accumulating clinical and experimental data have indicated that surgical procedures themselves may promote the appearance and progression of recurrent and metastatic lesions, only in recent years has renewed interest been taken in the mechanism by which metastasizing of cancer occurs following operative procedures. It is well proven now that surgery constitutes a risk factor for the promotion of pre-existing, possibly dormant micrometastases and the acceleration of new metastases through several mechanisms, including the release of neuroendocrine and stress hormones and wound healing pathway-associated immunosuppression, neovascularization, and tissue remodeling. These postoperative consequences synergistically facilitate the establishment of new metastases and the development of pre-existing micrometastases. While only in recent years the role of the peripheral nervous system has been recognized as another contributor to cancer development and metastasis, little is known about the contribution of tumor-associated neuronal and neuroglial elements in the metastatic disease related to surgical trauma and wound healing. Specifically, although numerous clinical and experimental data suggest that biopsy- and surgery-induced wound healing can promote survival and metastatic spread of residual and dormant malignant cells, the involvement of the tumor-associated neuroglial cells in the formation of metastases following tissue injury has not been well understood. Understanding the clinical significance and underlying mechanisms of neuroimmune regulation of surgery-associated metastasis will not only advance the field of neuro–immuno–oncology and contribute to basic science and translational oncology research but will also produce a strong foundation for developing novel mechanism-based therapeutic approaches that may protect patients against the oncologically adverse effects of primary tumor biopsy and excision.

Neurobiology of Cancer: the Role of β-Adrenergic Receptor Signaling in Various Tumor Environments

The development and progression of cancer depends on both tumor micro- and macroenvironments. In addition, psychosocial and spiritual “environments” might also affect cancer. It has been found that the nervous system, via neural and humoral pathways, significantly modulates processes related to cancer at the level of the tumor micro- and macroenvironments. The nervous system also mediates the effects of psychosocial and noetic factors on cancer. Importantly, data accumulated in the last two decades have clearly shown that effects of the nervous system on cancer initiation, progression, and the development of metastases are mediated by the sympathoadrenal system mainly via β-adrenergic receptor signaling. Here, we provide a new complex view of the role of β-adrenergic receptor signaling within the tumor micro- and macroenvironments as well as in mediating the effects of the psychosocial and spiritual environments. In addition, we describe potential preventive and therapeutic implications.

Increased cancer risk in polycystic ovary syndrome: An (un)sympathetic connection?

Women with polycystic ovary syndrome (PCOS) have been shown to have a higher incidence of cancer. It is suggested that several factors, including hyperinsulinemia, dyslipidemia, raised estrogen levels, chronic inflammation, and reduced apoptosis are responsible for this association. However, in this paper we propose the hypothesis that increased sympathetic activity may represent an important factor that interconnects PCOS and cancer. This hypothesis is based on two facts: a) in women with PCOS is found sympathetic hyperactivity and b) recent data showing a stimulatory effect of the sympathetic system on cancer initiation, progression, and development of metastases. If our hypothesis is correct, then new preventive approaches might be used to reduce cancer risk in women with PCOS.

E-Cigarettes and Cancer Risk

From the time of their introduction, the popularity of e-cigarettes (electronic nicotine-delivery systems) has been rising. This trend may reflect the general belief that e-cigarettes are a less hazardous alternative to combustible cigarettes. However, the potential cancer-related effects of increased activation of the sympathoadrenal system induced by the inhalation of nicotine, the primary component of the e-cigarettes, are completely overlooked. Therefore, the aim of this review is to describe mechanisms that may connect the use of e-cigarettes and an increased risk for cancer development, as well as their stimulatory effect on cancer progression. Available preclinical data indicate that activation of the sympathetic nervous system by nicotine inhaled from e-cigarettes may stimulate cancer development and growth by several mechanisms. This issue might be especially important for oncological patients as they may have the misconception that compared with combustible cigarettes, e-cigarettes represent a risk-free alternative.

Cardiac autonomic modulation impairments in advanced breast cancer patients

AIM

To compare cardiac autonomic modulation in early- versus advanced-stage breast cancer patients before any type of cancer treatment and investigate associated factors.

METHODS AND RESULTS

This cross-sectional study included women (30-69 years old) with primary diagnosis of breast cancer and women with benign breast tumors. We evaluated cardiac modulation by heart rate variability and assessed factors of anxiety, depression, physical activity, and other relevant medical variables. Patients were divided into three groups based on TNM staging of cancer severity: early-stage cancer (n = 42), advanced-stage cancer (n = 37), or benign breast tumors to serve as a control (n = 37). We analyzed heart rate variability in time and frequency domains. The advanced-stage cancer group had lower vagal modulation than early-stage and benign groups; also, the advance-stage group had lower overall heart rate variability when compared to benign conditions. Heart rate variability was influenced by age, menopausal status, and BMI.

CONCLUSIONS

Heart rate variability seems to be a promising, non-invasive tool for early diagnosis of autonomic dysfunction in breast cancer and detection of cardiovascular impairments at cancer diagnosis. Cardiac autonomic modulation is inversely associated with breast cancer staging.

Heart Rate Variability Markers as Correlates of Survival in Recipients of Hematopoietic Cell Transplantation

OBJECTIVES

To assess pre-/post-transplantation changes in autonomic tone, as measured by heart rate variability (HRV), among patients undergoing hematopoietic cell transplantation (HCT) and to look at those changes as they relate to post-transplantation survival rates. 
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SAMPLE & SETTING

Data were derived from a sample of 27 English-speaking patients undergoing allogeneic or autologous HCT at Stanford University. 
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METHODS & VARIABLES

A survival analysis using the Kaplan-Meier estimator was employed to explore whether increased HRV would enhance survival probabilities over time among patients undergoing HCT.
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RESULTS

An increased probability of survival was significantly related to increases in two HRV indexes.

IMPLICATIONS FOR NURSING

HRV may be a useful predictor of mortality among patients undergoing HCT. Interventions deliverable by nurses could be used to enhance HRV for patients identified as being at risk for early mortality.

Role of the nervous system in cancer metastasis

Cancer remains as one of the leading cause of death worldwide. The development of cancer involves an intricate process, wherein many identified and unidentified factors play a role. Although most studies have focused on the genetic abnormalities which initiate and promote cancer, there is overwhelming evidence that tumors interact within their environment by direct cell-to-cell contact and with signaling molecules, suggesting that cancer cells can influence their microenvironment and bidirectionally communicate with other systems. However, only in recent years the role of the nervous system has been recognized as a major contributor to cancer development and metastasis. The nervous system governs functional activities of many organs, and, as tumors are not independent organs within an organism, this system is integrally involved in tumor growth and progression.

Neural circuitry and immunity

Research during the last decade has significantly advanced our understanding of the molecular mechanisms at the interface between the nervous system and the immune system. Insight into bidirectional neuro-immune communication has characterized the nervous system as an important partner of the immune system in the regulation of inflammation. Neuronal pathways, including the vagus nerve-based inflammatory reflex, are physiological regulators of immune function and inflammation. In parallel, neuronal function is altered in conditions characterized by immune dysregulation and inflammation. Here, we review these regulatory mechanisms and describe the neural circuitry modulating immunity. Understanding these mechanisms reveals possibilities to use targeted neuromodulation as a therapeutic approach for inflammatory and autoimmune disorders. These findings and current clinical exploration of neuromodulation in the treatment of inflammatory diseases define the emerging field of Bioelectronic Medicine.

Changes of Brain Glucose Metabolism in the Pretreatment Patients with Non-Small Cell Lung Cancer: A Retrospective PET/CT Study

OBJECTIVE

The tumor-to-brain communication has been emphasized by recent converging evidences. This study aimed to compare the difference of brain glucose metabolism between patients with non-small cell lung cancer (NSCLC) and control subjects.

METHODS

NSCLC patients prior to oncotherapy and control subjects without malignancy confirmed by 6 months follow-up were collected and underwent the resting state 18F-fluoro-D-glucose (FDG) PET/CT. Normalized FDG metabolism was calculated by a signal intensity ratio of each brain region to whole brain. Brain glucose metabolism was compared between NSCLC patients and control group using two samples t-test and multivariate test by statistical parametric maps (SPM) software.

RESULTS

Compared with the control subjects (n = 76), both brain glucose hyper- and hypometabolism regions with significant statistical differences (P<0.01) were found in the NSCLC patients (n = 83). The hypermetabolism regions (bilateral insula, putamen, pallidum, thalamus, hippocampus and amygdala, the right side of cerebellum, orbital part of right inferior frontal gyrus and vermis) were component parts of visceral to brain signal transduction pathways, and the hypometabolism regions (the left superior parietal lobule, bilateral inferior parietal lobule and left fusiform gyrus) lied in dorsal attention network and visuospatial function areas.

CONCLUSIONS

The changes of brain glucose metabolism exist in NSCLC patients prior to oncotherapy, which might be attributed to lung-cancer related visceral sympathetic activation and decrease of dorsal attention network function.

Tumour-induced neoneurogenesis and perineural tumour growth: a mathematical approach

It is well-known that tumours induce the formation of a lymphatic and a blood vasculature around themselves. A similar but far less studied process occurs in relation to the nervous system and is referred to as neoneurogenesis. The relationship between tumour progression and the nervous system is still poorly understood and is likely to involve a multitude of factors. It is therefore relevant to study tumour-nerve interactions through mathematical modelling: this may reveal the most significant factors of the plethora of interacting elements regulating neoneurogenesis. The present work is a first attempt to model the neurobiological aspect of cancer development through a system of differential equations. The model confirms the experimental observations that a tumour is able to promote nerve formation/elongation around itself, and that high levels of nerve growth factor and axon guidance molecules are recorded in the presence of a tumour. Our results also reflect the observation that high stress levels (represented by higher norepinephrine release by sympathetic nerves) contribute to tumour development and spread, indicating a mutually beneficial relationship between tumour cells and neurons. The model predictions suggest novel therapeutic strategies, aimed at blocking the stress effects on tumour growth and dissemination.

Dimethyl sulfoxide-caused changes in pro- and anti-angiogenic factor levels could contribute to an anti-angiogenic response in HeLa cells

Dimethyl sulfoxide (DMSO) is widely used in biological research as a general solvent. While it has been previously demonstrated that DMSO possesses a wide range of pharmacological effects, there is no published work regarding the effects of DMSO on pro-angiogenic factor levels. This study was designed to investigate the possible effects of DMSO on the levels of three pro-angiogenic factors released from HeLa cells in vitro. Cells were treated with two different and previously determined concentrations of DMSO. The cytotoxic effects of DMSO concentrations on HeLa cells were determined via MTT. Survival rates of DMSO-treated cells were determined by Invitrogen live/dead viability/cytotoxicity kit and trypan blue exclusion assay. Changes in the pro-angiogenic levels in media were evaluated by Cayman's Substance P Enzyme Immunoassay ELISA kit. Vascular endothelial growth factor ELISA kit and interferon gamma ELISA kit for substance P, VEGF and IFNγ respectively. Changes in substance P levels were corrected by standard western blotting. Changes in VEGF and IFNγ levels were corrected both by western blot and real time PCR. Treatment with 1.4 μM DMSO caused a time-dependent inhibition of cell proliferation at 24, 48 and 72 h. 1.4 μM DMSO caused a significant reduction in VEGF levels at 72 h of incubation and sharp increases in IFNγ levels at both 48 and 72 h of incubation. According to real time PCR analyses, DMSO (1.4 μM) exhibited an inhibitory effect on VEGF but acted as an augmenter of IFNγ release on HeLa cells in vitro. This is the first report showing that the general solvent DMSO suppressed HeLa cell proliferation, decreased the levels of two pro-angiogenic factors (substance P and VEGF) and increased the release of an anti-angiogenic factor IFNγ in vitro.

Circadian disruption and biomarkers of tumor progression in breast cancer patients awaiting surgery

Psychological distress, which can begin with cancer diagnosis and continue with treatment, is linked with circadian and endocrine disruption. In turn, circadian/endocrine factors are potent modulators of cancer progression. We hypothesized that circadian rest-activity rhythm disruption, distress, and diurnal cortisol rhythms would be associated with biomarkers of tumor progression in the peripheral blood of women awaiting breast cancer surgery. Breast cancer patients (n=43) provided actigraphic data on rest-activity rhythm, cancer-specific distress (IES, POMS), saliva samples for assessment of diurnal cortisol rhythm, cortisol awakening response (CAR), and diurnal mean. Ten potential markers of tumor progression were quantified in serum samples and grouped by exploratory factor analysis. Analyses yielded three factors, which appear to include biomarkers reflecting different aspects of tumor progression. Elevated factor scores indicate both high levels and strong clustering among serum signals. Factor 1 included VEGF, MMP-9, and TGF-β; suggesting tumor invasion/immunosuppression. Factor 2 included IL-1β, TNF-α, IL-6R, MCP-1; suggesting inflammation/chemotaxis. Factor 3 included IL-6, IL-12, IFN-γ; suggesting inflammation/TH1-type immunity. Hierarchical regressions adjusting age, stage and socioeconomic status examined associations of circadian, distress, and endocrine variables with these three factor scores. Patients with poor circadian coordination as measured by rest-activity rhythms had higher Factor 1 scores (R(2)=.160, p=.038). Patients with elevated CAR also had higher Factor 1 scores (R(2)=.293, p=.020). These relationships appeared to be driven largely by VEGF concentrations. Distress was not related to tumor-relevant biomarkers, and no other significant relationships emerged. Women with strong circadian activity rhythms showed less evidence of tumor promotion and/or progression as indicated by peripheral blood biomarkers. The study was not equipped to discern the cause of these associations. Circadian/endocrine aberrations may be a manifestation of systemic effects of aggressive tumors. Alternatively, these results raise the possibility that, among patients with active breast tumors, disruption of circadian activity rhythms and elevated CAR may facilitate tumor promotion and progression.

Higher vagal activity as related to survival in patients with advanced breast cancer: an analysis of autonomic dysregulation

OBJECTIVE

High levels of high-frequency heart rate variability (HF-HRV), related to parasympathetic-nervous-system functioning, have been associated with longer survival in patients with myocardial infarction and acute trauma and in patients undergoing palliative care. From animal studies linking higher vagal activity with better immune system functioning and reduced metastases, we hypothesized that higher HF-HRV would predict longer survival in patients with metastatic or recurrent breast cancer (MRBC).

METHODS

Eighty-seven patients with MRBC participated in a laboratory task including a 5-minute resting baseline electrocardiogram. HF-HRV was computed as the natural logarithm of the summed power spectral density of R-R intervals (0.15-0.50 Hz). In this secondary analysis of a study testing whether diurnal cortisol slope predicted survival, we tested the association between resting baseline HF-HRV on survival using Cox proportional hazards models.

RESULTS

A total of 50 patients died during a median follow-up of 7.99 years. Higher baseline HF-HRV predicted significantly longer survival, with a hazard ratio of 0.75 (95% confidence interval = 0.60-0.92, p = .006). Visceral metastasis status and baseline heart rate were related to both HF-HRV and survival. However, a combination of HF-HRV and heart rate further improved survival prediction, with a hazard ratio of 0.64 (95% confidence interval = 0.48-0.85, p = .002).

CONCLUSIONS

Vagal activity of patients with MRBC strongly predicted their survival, extending the known predictive window of HF-HRV in cancer beyond palliative care. Vagal activity can be altered by behavioral, pharmacological, and surgical interventions and may be a promising target for extending life expectancy in patients with metastasizing cancer.

Pituitary transcriptome profile of liver cancer mice with different syndromes reveals the relevance of pituitary to the cancer and syndromes

OBJECTIVE

To investigate the relevance of the pituitary to liver syndromes and cancer by studying the pituitary transcriptome profile in liver cancer mice with different syndromes.

METHODS

The quantitative four diagnosis and syndrome differentiation methods were used to screen normal control mice without syndromes (NC), liver cancer mice with poisonous pathogenic factors syndrome (PPFS), and Qi deficiency syndrome mice (QDS). An Affymetrix GeneChip Mouse Exon 1.0 ST Array was performed to detect the gene expression of different groups. Gene clustering was applied to analyze the gene expression patterns of the PPFS and QDS groups compared with the NC group. The transcriptional networks analysis tool, FunNet, was used to enrich the biological categories of differentially expressed genes in the PPFS and QDS groups.

RESULTS

Biological categories of differentially expressed genes showed that excessive metabolism and extracellular matrix interaction, insufficient communication of cells (especially nerve cells), and the bidirectional regulation of genetic information processing were enriched in both syndromes. However, the degree of excessive metabolism in the PPFS group was higher than that in the QDS group. The hyperfunction of cancer and infection, and the hypofunction of the nervous and endocrine systems were obvious in the QDS group.

CONCLUSION

The pituitary plays an important role in the development of liver cancer and syndromes. This study further studied the role of the pituitary in the combination of disease and syndromes.

Effect of depression on diagnosis, treatment, and mortality of men with clinically localized prostate cancer

PURPOSE

Although demographic, clinicopathologic, and socioeconomic differences may affect treatment and outcomes of prostate cancer, the effect of mental health disorders remains unclear. We assessed the effect of previously diagnosed depression on outcomes of men with newly diagnosed prostate cancer.

PATIENTS AND METHODS

We performed a population-based observational cohort study using Surveillance, Epidemiology, and End Results-Medicare linked data of 41,275 men diagnosed with clinically localized prostate cancer from 2004 to 2007. We identified 1,894 men with a depressive disorder in the 2 years before the prostate cancer diagnosis and determined its effect on treatment and survival.

RESULTS

Men with depressive disorder were older, white or Hispanic, unmarried, resided in nonmetropolitan areas and areas of lower median income, and had more comorbidities (P < .05 for all), but there was no variation in clinicopathologic characteristics. In adjusted analyses, men with depressive disorder were more likely to undergo expectant management for low-, intermediate-, and high-risk disease (P ≤ .05, respectively). Conversely, depressed men were less likely to undergo definitive therapy (surgery or radiation) across all risk strata (P < .01, respectively). Depressed men experienced worse overall mortality across risk strata (low: relative risk [RR], 1.86; 95% CI, 1.48 to 2.33; P < .001; intermediate: RR, 1.25; 95% CI, 1.06 to 1.49; P = .01; high: RR, 1.16; 95% CI, 1.03 to 1.32; P = .02).

CONCLUSION

Men with intermediate- or high-risk prostate cancer and a recent diagnosis of depression are less likely to undergo definitive treatment and experience worse overall survival. The effect of depression disorders on prostate cancer treatment and survivorship warrants further study, because both conditions are relatively common in men in the United States.

Review of psychotherapeutic interventions on depression in cancer patients and their impact on disease progression

Depression, ranging from mild to severe, is the most frequently found psychological symptom among individuals with cancer. Depression in cancer patients has been known to mitigate emotional distress, quality of life, adherence to medical treatment, and overall health outcomes. Specifically, depression has been associated with impaired immune response and with poorer survival in patients with cancer. Various studies have found that psychotherapeutic interventions are effective in reducing symptoms of depression, which in turn could affect disease progression and mortality. This paper provides updated information on psychotherapeutic interventions geared towards cancer patients suffering from depressive disorders, and its impact on disease progression. PubMed, Cochrane Library database, PsycINFO and PsycARTICLES databases were searched from January 1980 through August 2013 using key words: psychotherapy, treatment, oncology, cancer, psycho-oncology, psychosocial issues, psychosocial stress, depression, mood disorder, and psychoneuroimmunology.

Diurnal cortisol rhythm as a predictor of lung cancer survival

BACKGROUND

Poorly coordinated diurnal cortisol and circadian rest-activity rhythms predict earlier mortality in metastatic breast and colorectal cancer, respectively. We examined the prognostic value of the diurnal cortisol rhythm in lung cancer.

METHODS

Lung cancer patients (n=62, 34 female) were within 5 years of diagnosis and had primarily non small-cell lung cancer, with disease stage ranging from early to advanced. Saliva collected over two days allowed calculation of the diurnal cortisol slope and the cortisol awakening response (CAR). Lymphocyte numbers and subsets were measured by flow cytometry. Survival data were obtained for 57 patients. Cox Proportional Hazards analyses were used to test the prognostic value of the diurnal cortisol rhythm on survival calculated both from study entry and from initial diagnosis.

RESULTS

The diurnal cortisol slope predicted subsequent survival over three years. Early mortality occurred among patients with higher slopes, or relatively "flat" rhythms indicating lack of normal diurnal variation (Cox Proportional Hazards p=.009). Cortisol slope also predicted survival time from initial diagnosis (p=.012). Flattened profiles were linked with male gender (t=2.04, df=59, p=.046) and low total and cytotoxic T cell lymphocyte counts (r=-.39 and -.30, p=.004 and .035, respectively). After adjustment for possible confounding factors, diurnal slope remained a significant, independent predictor of survival.

CONCLUSIONS

Flattening of the diurnal cortisol rhythm predicts early lung cancer death. Data contribute to growing evidence that circadian disruption accelerates tumor progression.

Role of the nervous system in cancer metastasis

The notion that tumors lack innervation was proposed several years ago. However, nerve fibers are irregulatedly found in some tumor tissues. Their terminals interaction with cancer cells are considered to be neuro-neoplastic synapses. Moreover, neural-related factors, which are important players in the development and activity of the nervous system, have been found in cancer cells. Thus, they establish a direct connection between the nervous system and tumor cells. They modulate the process of metastasis, including degradation of base membranes, cancer cell invasion, migration, extravasation and colonization. Peripheral nerve invasion provides another pathway for the spread of cancer cells when blood and lymphatic metastases are absent, which is based on the interactions between the microenvironments of nerve fibers and tumor cells. The nervous system also modulates angiogenesis, the tumor microenvironment, bone marrow, immune functions and inflammatory pathways to influence metastases. Denervation of the tumor has been reported to enhance cancer metastasis. Stress, social isolation and other emotional factors may increase distant metastasis through releasing hormones from the brain, the hypothalamic-pituitary-adrenal axis and autonomic nervous system. Disruption of circadian rhythms will also promote cancer metastasis through direct and indirect actions of the nervous system. Therefore, the nervous system plays an important role in cancer metastasis.

Thalidomide and irradiation combination therapy increases substance P levels in vitro

Thalidomide is an anti-angiogenic agent that is used in the treatment of cancer. However, in many cases, particularly in patients with breast cancer, thalidomide treatment alone is insufficient and must be combined with other drugs or therapies. In the clinical setting, thalidomide is most commonly used in combination with radiation therapy. However, the exact mechanisms of its effect are unkown. Radiotherapy alters the expression of substance P, which is considered a crucial pro-angiogenic peptide. To determine whether thalidomide and radiotherapy in combination overcome the limitations of each as monotherapy, we examined the effects of the combination on the growth of breast cancer cells as well as on the expression of substance P in vitro. Mouse breast cancer cells (4T1) and cells produced from metastatic lesions (4THMpc) were treated with radiotherapy (RT) (45 Gy) alone, thalidomide (Thal) (40 μg/ml) alone or combination therapy (40 μg/ml Thal + 45 Gy RT), and compared with control cells. MTS, Live/Dead and trypan blue exclusion assays were used to evaluate the cytotoxic effects of the treatments. The levels of substance P in the conditioned media and in the cell lysates were determined by a substance P ELISA kit, and changes in the protein content were analyzed by Western blotting. Thalidomide alone resulted in a significant inhibition in the growth of the 4T1 (34.1%) and 4THMpc (52.6%) cell lines. RT alone inhibited the growth of the 4T1 (19.2%) and 4THMpc (23.31%) cell lines. The combination therapy enhanced the growth inhibition noted in the 4T1 (47.9%) and 4THMpc (62.03%) cell lines. The expression of substance P in the conditioned media and in the cell lysates increased within 72 h of RT. This increase was significantly enhanced with the combination therapy. These data indicate that thalidomide inhibits breast cancer cell growth and potentiates the anti-tumor effects of radiation at appropriate doses.

Decrease in depression symptoms is associated with longer survival in patients with metastatic breast cancer: a secondary analysis

PURPOSE

Numerous studies have examined the comorbidity of depression with cancer, and some have indicated that depression may be associated with cancer progression or survival. However, few studies have assessed whether changes in depression symptoms are associated with survival.

METHODS

In a secondary analysis of a randomized trial of supportive-expressive group therapy, 125 women with metastatic breast cancer (MBC) completed a depression symptom measure (Center for Epidemiologic Studies-Depression Scale [CES-D]) at baseline and were randomly assigned to a treatment group or to a control group that received educational materials. At baseline and three follow-up points, 101 of 125 women completed a depression symptom measure. We used these data in a Cox proportional hazards analysis to examine whether decreasing depression symptoms over the first year of the study (the length of the intervention) would be associated with longer survival.

RESULTS

Median survival time was 53.6 months for women with decreasing CES-D scores over 1 year and 25.1 months for women with increasing CES-D scores. There was a significant effect of change in CES-D over the first year on survival out to 14 years (P = .007) but no significant interaction between treatment condition and CES-D change on survival. Neither demographic nor medical variables explained this association.

CONCLUSION

Decreasing depression symptoms over the first year were associated with longer subsequent survival for women with MBC in this sample. Further research is necessary to confirm this hypothesis in other samples, and causation cannot be assumed based on this analysis.

Psychogenic carcinogenesis: carcinogenesis is without exogenic carcinogens

The history of researches of a problem of cancer has cleared a number of key cellular-molecular-genetic mechanisms of carcinogenesis, however process of carcinogenesis, is still out of control and a world forecast is unfavorable despite the advanced pathogenetically focused medication and excellent results of cancer treatment in vivo. Numerous researches have shown that chronic psycho-emotional stress by means of stressful hormones and endogenous mutagens (reactive oxygen and nitrogen species) are capable to damage cells DNA and to compromise immune system. Actually, chronic psycho-emotional stress is capable to activate the key mechanisms of carcinogenesis. It specifies an opportunity of existence psychogenic carcinogenesis--"carcinogenesis is without carcinogens" which can function as independent and in a combination with physical, chemical and biological carcinogens, strengthening their carcinogenic effect. At cancer patients with psychogenically induced carcinogenesis use only the somatically focused therapy of a cancer (surgery, radiotherapy, chemotherapy, immunotherapy), apparently, is not enough for achievement of steady remission. At psychogenically induced carcinogenesis creation of effective anticarcinogenic medicines is also apparently problematic. The presented hypothesis allows to hope for search in the future of diagnostic criteria of revealing of persons with psychogenic also and development of new strategy of the second prophylactic, treatments and rehabilitations such cancer patients. The hypothesis psychogenic carcinogenesis expands existing representations about pathogenesis of malignant tumors and forms holistic approach to the decision of problems of a cancer at the person.