Effects on DNA Damage and/or Repair Processes as Biological Mechanisms Linking Psychological Stress to Cancer Risk

Feasibility and Acceptability Evaluation of a Digital Therapeutic Program for Improving Cancer Prevention: A Quasi-experimental Pre-post Interventional Pilot Study

Previous studies have proved that healthy behaviors hinder the onset and progression of tumors. Digital therapeutics (DTx), playing a pivotal role in facilitating behavioral adjustments through educational interventions, lifestyle support, and symptom monitoring, contribute to the goal of tumor prevention. We aim to optimize the evaluation of the feasibility and acceptability of DTx for cancer prevention. This involves assessing AITI's daily activity rates and user feedback, and comparing changes in behavioral habits and differences in SF-36 before and after the intervention. In a 4-week trial with 57 participants engaging actively, we found both the average daily activity rate and 4-week retention rate at 35 (61.4%). The USE Questionnaire scores (validity, ease of use, acquisition, and satisfaction) ranged from 68.06 to 83.10, indicating AITI's user-friendliness and acceptability. Furthermore, positive habit changes were noted among participants in exercise and diet (p < 0.0001), suggesting the effectiveness of the DTx approach in modifying behavioral habits related to physical activity and nutrition. This pilot study underscores the potential of DTx in advancing cancer prevention. However, larger and longer studies are needed to comprehensively assess its impact.

Unraveling the link between cardiorespiratory fitness and cancer: a state-of-the-art review

Cardiorespiratory fitness (CRF) not only reflects an individual's capacity to perform physical activities but also encapsulates broader effects on the basic biology of aging. This review aims to summarize the evidence on the influence of CRF on overall and site-specific cancer risks. It delves into the biological mechanisms through which CRF may exert its effects, explores the clinical implications of these findings, identifies gaps in the current evidence base, and suggests directions for future research. The synthesis of findings reveals that higher CRF levels (general threshold of > 7 METs) are consistently associated with a reduced risk of a range of cancers, including head and neck, lung, breast, gastrointestinal, particularly pancreatic and colorectal, bladder, overall cancer incidence and mortality, and potentially stomach and liver, bile duct, and gall bladder cancers. These inverse associations between CRF and cancer risk do not generally differ across age groups, sex, race, or adiposity, suggesting a universal protective effect of CRF. Nonetheless, evidence linking CRF with skin, mouth and pharynx, kidney, and endometrial cancers is limited and inconclusive. Conversely, higher CRF levels may be potentially linked to an increased risk of prostate cancer and hematological malignancies, such as leukemia and myeloma, although the evidence is still not conclusive. CRF appears to play a significant role in reducing the risk of several cancers through various biological mechanisms, including inflammation reduction, immune system enhancement, hormonal regulation, and metabolic improvements. Overall, enhancing CRF through regular physical activity offers a vital, accessible strategy for reducing cancer risk and extending the health span. Future research should aim to fill the existing evidence gaps regarding specific cancers and elucidate the detailed dose-response relationships between CRF levels and cancer risk. Studies are also needed to elucidate the causal relationships and mechanistic pathways linking CRF to cancer outcomes.

Role of stress in the pathogenesis of cancer (Review)

Stress is a state of disrupted homeostasis, triggered by intrinsic or extrinsic factors, the stressors, which are counteracted by various physiological and behavioural adaptive responses. Stress has been linked to cancer development and incidence for decades; however, epidemiological studies and clinical trials have yielded contradictory results. The present review discusses the effects of stress on cancer development and the various underlying mechanisms. Animal studies have revealed a clear link between stress and cancer progression, revealing molecular, cellular and endocrine processes that are implicated in these effects. Thus, stress hormones, their receptor systems and their intracellular molecular pathways mediate the effects of stress on cancer initiation, progression and the development of metastases. The mechanisms linking stress and cancer progression can either be indirect, mediated by changes in the cancer microenvironment or immune system dysregulation, or direct, through the binding of neuroendocrine stress‑related signalling molecules to cancer cell receptors. Stress affects numerous anti‑ and pro‑cancer immune system components, including host resistance to metastasis, tumour retention and/or immune suppression. Chronic psychological stress through the elevation of catecholamine levels may increase cancer cell death resistance. On the whole, stress is linked to cancer development and incidence, with psychological stressors playing a crucial role. Animal studies have revealed a better link than human ones, with stress‑related hormones influencing tumour development, migration, invasion and cell proliferation. Randomized controlled trials are required to further evaluate the long‑term cancer outcomes of stress and its management.

Urinary levels of cortisol but not catecholamines are associated with those of 8-hydroxy-2'-deoxyguanosine in uncomplicated primary hypertension

OBJECTIVES

The relationships between stress hormones and oxidative DNA damage have not yet been explored in human hypertension. We investigated the associations of urinary levels of cortisol or catecholamines with those of 8-hydroxy-2'-deoxyguanosine, a marker of oxidative DNA damage in primary hypertension.

METHODS

Untreated 156 primary hypertensives without apparent cardiovascular diseases were entered into the study. Following blood sampling after an overnight fast, 24-h blood pressure monitoring and 24-h urinary sampling were performed simultaneously to determine 24-h averaged values for blood pressure and urinary levels of cortisol, catecholamines and 8-hydroxy-2'-deoxyguanosine.

RESULTS

Urinary cortisol significantly correlated positively with urinary 8-hydroxy-2'-deoxyguanosine in all studied participants (r = 0.334, P < 0.001). Contrary, either urinary adrenaline or urinary noradrenaline did not significantly correlate with urinary 8-hydroxy-2'-deoxyguanosine (r = 0.050, P = 0.553 or r = 0.063, P = 0.435). Additionally, the positive association of urinary cortisol with urinary 8-hydroxy-2'-deoxyguanosine remained highly significant after the adjustments for multiple confounders of oxidative stress such as age, gender, body mass index, smoking status, 24-h blood pressure, C-reactive protein and estimated glomerular filtration rate (partial r = 0.323, P < 0.001), although only approximately 10% of the variance in urinary cortisol was attributable to differences in urinary 8-OHdG (partial r2 = 0.104). Thus, our data indicate that cortisol but not catecholamines could at least partially contribute to the occurrence of oxidative DNA damage in primary hypertensives.

CONCLUSION

The present study suggested the possibility that the overactivation of hypothalamic-pituitary-adrenal axis rather than sympathoadrenal system could enhance oxidative stress and attendant DNA oxidation in uncomplicated primary hypertension.

Wip1 contributes to the adaptation of HepG2 human liver cancer cells to stress hormone-induced DNA damage

Numerous studies have shown that the release of stress hormones resulting from repeated exposure to chronic psychological stress increases DNA damage and promotes tumorigenesis. However, the mechanisms that enable cancerous cells adapt to stress hormone-induced DNA damage and survive remain unclear. The present study aimed to investigate the impact of stress hormones on the survival of liver cancer cells and the underlying mechanism. HepG2 human liver cancer cells were treated with dexamethasone (DEX), epinephrine (EPI) and norepinephrine (NE) and subjected to the testing of DNA damage, cell survival and cell apoptosis by alkaline comet assay, CCK-8 viability assay and flow cytometry, respectively. The protein expression levels of DNA damage response factors were determined by western blotting analysis. The results revealed that treatment of HepG2 cells with DEX, EPI and NE induced DNA damage without affecting cell survival or inducing apoptosis. The protein levels of wild-type p53-induced phosphatase 1 (Wip1), a type 2C family serine/threonine phosphatase, were increased, and the dephosphorylation of DNA damage response factors, including phosphorylated (p-)ataxia-telangiectasia mutated and p-checkpoint kinase 2, occurred following treatment with DEX, EPI and NE. In addition, a cycloheximide chase assay was performed to explore the protein stability under treatment with stress hormones. Compared with vehicle-treated cells, Wip1 exhibited increased protein stability in stress hormone-treated HepG2 cells. Eventually, the depletion of Wip1 using small interfering RNA verified the role of Wip1 in the modulation of stress hormone-induced DNA damage. These findings suggest that cancerous cells likely adapt to stress hormone-induced DNA damage via Wip1 upregulation. The present study provides an insight into the underlying mechanism that links chronic psychological stress with tumor growth and progression.

Neighborhood disadvantage and lung cancer risk in a national cohort of never smoking Black women

BACKGROUND

Compared to women of other races who have never smoked, Black women have a higher risk of lung cancer. Whether neighborhood disadvantage, which Black women experience at higher rates than other women, is linked to never-smoking lung cancer risk remains unclear. This study investigates the association of neighborhood disadvantage and lung cancer risk in Black never-smoking women.

METHODS AND MATERIALS

This research utilized data from the Black Women's Health Study, a prospective cohort of 59,000 Black women recruited from across the US in 1995 and followed by biennial questionnaires. Associations of lung cancer incidence with neighborhood-level factors (including two composite variables derived from Census Bureau data: neighborhood socioeconomic status and neighborhood concentrated disadvantage), secondhand smoke exposure, and PM_2.5 were estimated using Fine-Gray subdistribution hazard models.

RESULTS

Among 37,650 never-smokers, 77 were diagnosed with lung cancer during follow-up from 1995 to 2018. The adjusted subdistribution hazard ratio (sHR) of lung cancer incidence with ten unit increase in neighborhood concentrated disadvantage index was 1.30 (95 % CI: 1.04, 1.63, p = 0.023). Exposure to secondhand smoke at work was associated with increased risk (sHR = 1.93, 95 % CI: 1.21, 3.10, p = 0.006), but exposure to secondhand smoke at home and PM_2.5 was not.

CONCLUSION

Worse neighborhood concentrated disadvantage was associated with increased lung cancer risk in Black women who never smoked. These findings suggest that non-tobacco-related factors in disadvantaged neighborhoods may be linked to lung cancer risk in Black women and that these factors must be understood and targeted to achieve health equity.

Long-term exposure to wildfires and cancer incidence in Canada: a population-based observational cohort study

BACKGROUND

Wildfires emit many carcinogenic pollutants that contaminate air, water, terrestrial, and indoor environments. However, little is known about the relationship between exposure to wildfires and cancer risk. We aimed to assess the associations between residential exposure to wildfires and the incidence of several cancer outcomes (lung cancer, brain cancer, non-Hodgkin lymphoma, multiple myeloma, and leukaemia) in Canada.

METHODS

We did a population-based observational cohort study of participants in the 1996 Canadian Census Health and Environment Cohort. The 1996 Canadian Census Health and Environment Cohort is a nationally representative sample of Canadian adults, followed up for cancer incidence and mortality from 1996 to 2015. For this analysis, we excluded participants who lived in major Canadian cities (with a population size greater than 1·5 million people), recent immigrants, and individuals younger than 25 years or 90 years of age or older at baseline. Exposures to wildfires were assigned on the basis of area burned within a 20 km or 50 km radius of residential locations and updated for annual residential mobility. Multivariable Cox proportional hazards models were used to estimate associations between exposure to wildfires and specific cancers associated with carcinogenic compounds released by wildfires, including lung and brain cancer, non-Hodgkin lymphoma, multiple myeloma, and leukaemia, adjusted for many personal and neighbourhood-level covariates.

FINDINGS

Our analyses included more than 2 million people followed up for a median of 20 years, for a total of 34 million person-years. Wildfire exposure was associated with slightly increased incidence of lung cancer and brain tumours. For example, cohort members exposed to a wildfire within 50 km of residential locations in the past 10 years had a 4·9% relatively higher incidence (adjusted hazard ratio [HR] 1·049, 95% CI 1·028-1·071) of lung cancer than unexposed populations, and a 10% relatively higher incidence (adjusted HR 1·100, 1·026-1·179) of brain tumours. Similar associations were observed for the 20 km buffer size. Wildfires were not associated with haematological cancers in this study, and concentration-response trends were not readily apparent when area burned was modelled as a continuous variable.

INTERPRETATION

Long-term exposure to wildfires might increase the risk of lung cancer and brain tumours. Further work is needed to develop long-term estimates of wildfire exposures that capture the complex mixture of environmental pollutants released during these events.

FUNDING

Canadian Institute for Health Research and Fonds de recherche du Quebec.

Predisposing factors for increased cortisol levels in oral cancer patients

Cancer patients may have a dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and abnormal secretion of cortisol. Increased cortisol levels have been associated with worse prognosis in patients with different types of tumors. Although anxiety and depression can trigger an abnormal cortisol secretion, little is known regarding the influence of these emotional disorders on HPA axis dysregulation in cancer patients when evaluating together with demographic, clinicopathological and biobehavioral variables. This cross-sectional study analyzed the pre-treatment plasma cortisol levels of 133 patients with oral squamous cell carcinoma (OSCC) and its association with demographic, clinicopathological, biobehavioral and psychological variables. Plasma cortisol levels were measured by electrochemiluminescence, and anxiety and depression symptoms were assessed using Beck Anxiety Inventory (BAI) and Depression (BDI), respectively. Demographic, clinicopathological and biobehavioral data were collected from patients' medical records. Results from multivariate analysis showed that the occurrence of cancer-induced pain was predictive for higher cortisol levels (OR = 5.388, p = 0.003). Men with OSCC were 4.5 times more likely to have higher plasma cortisol levels than women (OR = 4.472, p = 0.018). The effect of sex on cortisol concentrations was lost in the adjusted model for clinical staging (OR = 2.945, p = 0.116). The absence of chronic alcohol consumption history was a protective factor for highest hormone concentrations in oral cancer patients (OR = 0.104, p = 0.004). Anxiety symptoms measured by BAI as “hands trembling” (OR = 0.192, p = 0.016) and being “nervous” (OR = 0.207, p = 0.0004) were associated with lower cortisol levels. In contrast, the feeling of “fear of losing control” was a risk factor for highest hormone concentrations (OR = 6.508, p = 0.0004). The global score and specific symptoms of depression measured by the BDI were not predictive for plasma hormone levels (p > 0.05). Together, our results show that pain, alcohol consumption and feeling fear are independent factors for increased systemic cortisol levels in patients with oral cancer. Therefore, psychological intervention, as well as control of pain and alcohol consumption, should be considered to prevent the negative effects of cortisol secretion dysregulation in cancer patients.

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Pain, alcoholism and fear increase cortisol levels in cancer patients.

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Different anxiety symptoms can inversely predict cortisol systemic levels.

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Management of pain, alcoholism, and fear could prevent HPA axis dysregulation.

The influence of biological and lifestyle factors on circulating cell-free DNA in blood plasma

Research and clinical use of circulating cell-free DNA (cirDNA) is expanding rapidly; however, there remain large gaps in our understanding of the influence of lifestyle and biological factors on the amount of cirDNA present in blood. Here, we review 66 individual studies of cirDNA levels and lifestyle and biological factors, including exercise (acute and chronic), alcohol consumption, occupational hazard exposure, smoking, body mass index, menstruation, hypertension, circadian rhythm, stress, biological sex and age. Despite technical and methodological inconsistences across studies, we identify acute exercise as a significant influence on cirDNA levels. Given the large increase in cirDNA induced by acute exercise, we recommend that controlling for physical activity prior to blood collection is routinely incorporated into study design when total cirDNA levels are of interest. We also highlight appropriate selection and complete reporting of laboratory protocols as important for improving the reproducibility cirDNA studies and ability to critically evaluate the results.

Stress and its contribution to the development of depression symptoms are reduced in caregivers of elderly with higher educational level

Caregivers of elderly people with neurodegenerative diseases are highly vulnerable to stressful situations and mood disorders due to their work conditions. Stress has been associated with an increased risk of developing depression, and studies have supported that caffeine consumption can act as an independent protective factor for disorder. This study investigated indexes of stress and depression symptoms in caregivers of the elderly with neurodegenerative diseases, their caffeine intake and the association between stress and depressive symptoms with the salivary biomarkers cortisol, nitric oxide and DNA damage. Participants (n = 81) were recruited from the community between July 2018 and April 2019. Stress was assessed using Lipp's Inventory of Stress Symptoms, and depressive symptoms were measured using the Hamilton Depressive Rating Scale. Participants provided a 72-hour recall of their diet to measure caffeine intake. Saliva samples were used to measure cortisol and nitric oxide. DNA damage was measured through micronuclei frequency after swabbing on the buccal mucosa. The majority of caregivers displayed stress and depressive symptoms. Stress was associated with educational level, tobacco use and total DNA damage. The indexes found in this population were not associated with caffeine intake or other salivary biomarkers, indicating that only some salivary molecules could be used as biomarkers for stress-related disorders. Caregivers of the elderly are exposed to stressful situations daily, however, we observed that educational level can reduce the psychological symptoms of stress and thus reduce the negative impact on quality of life.

The Role of Psychologic Stress in Cancer Initiation: Clinical Relevance and Potential Molecular Mechanisms

The hypothesis that the physiologic response to psychologic stress influences the initiation of cancer is highly controversial. The link between initiating stressors, the psychologic stress response, and disease is plausible, considering that the stress response is associated with defined physiologic outcomes and molecular mechanisms. In light of this, we review the clinical relevance of psychologic stress on the risk of cancer, and we propose potential molecular pathways that may link the stress response to early stages of malignant cell transformation.

Stress hormones promote DNA damage in human oral keratinocytes

Chronic stress increases the systemic levels of stress hormones norepinephrine and cortisol. As well as tobacco-specific carcinogen NNK (4-(methylnitrosamine)-1-(3-pyridyl)-1-butanone), they can induce expressive DNA damage contributing to the cancer development. However, it is unknown whether stress hormones have genotoxic effects in oral keratinocytes. This study investigated the effects of stress hormones on DNA damage in a human oral keratinocyte cell line (NOK-SI). NOK-SI cells stimulated with norepinephrine or cortisol showed higher DNA damage compared to untreated cells. Norepinephrine-induced DNA damage was reversed by pre-treatment with beta-adrenergic blocker propranolol. Cells treated with NNK combined to norepinephrine displayed reduced levels of caspases 3 and 7. Cortisol also reduced the activity of pro-apoptotic enzymes. NNK or norepinephrine promoted single-strand breaks and alkali-label side breaks in the DNA of NOK-SI cells. Pre-treatment of cells with propranolol abolished these effects. Carcinogen NNK in the presence or absence of cortisol also induced DNA damage of these cells. The genotoxic effects of cortisol alone and hormone combined with NNK were blocked partially and totally, respectively, by the glucocorticoid receptor antagonist RU486. DNA damage promoted by NNK or cortisol and carcinogen combined to the hormone led to intracellular γH2AX accumulation. The effects caused by NNK and cortisol were reversed by propranolol and glucocorticoid receptor antagonist RU486, respectively. Propranolol inhibited the oxidation of basis induced by NNK in the presence of DNA-formamidopyrimidine glycosylase. DNA breaks induced by norepinephrine in the presence or absence of NNK resulted in higher 8OHdG cellular levels. This effect was also induced through beta-adrenergic receptors. Together, these findings indicate that stress hormones induce DNA damage of oral keratinocytes and could contribute to oral carcinogenesis.

Chronic stress caused by maternal separation is a possible risk factor for the development of 7,12-dimethyl benzo anthracene-induced breast tumors in rats

BACKGROUND

Chronic stress has been investigated as a risk factor for breast cancer. Maternal separation (MS) of rats has been used as a chronic stress model that alters certain systemic functions, such as the immune response.

OBJECTIVE

The aim of this study was to determine the possible effect of MS on the development of breast tumors induced by 7,12-dimethyl benzo anthracene (DMBA).

METHODOLOGY

postnatal day (PND) 1 female Wistar rats were divided into four experimental groups that either were or were not subjected to MS and either received or did not receive DMBA. For MS, PND 1 to 21 pups were separated from their mothers for 360 min/day. On PND 30, carcinomas were induced in mammary glands using DMBA. Body weight was evaluated, and the injected region was palpated. In addition, the mammary glands were subjected to histological examination, and corticosterone levels were determined in all groups.

RESULTS

DMBA-induced groups had significantly lower body weight gain compared with the non-DMBA-induced groups. Maternal separation increased the incidence of preneoplastic changes and breast carcinogenesis in DMBA-treated animals compared with control animals. Corticosterone levels were increased in both DMBA-induced and MS groups without interaction.

CONCLUSION

MS is a possible risk factor for DMBA-induced preneoplastic changes and breast tumors in rats.

Synergistic Effects of Chronic Restraint-Induced Stress and Low-Dose 56Fe-particle Irradiation on Induction of Chromosomal Aberrations in Trp53-Heterozygous Mice

Astronauts can develop psychological stress (PS) during space flights due to the enclosed environment, microgravity, altered light-dark cycles, and risks of equipment failure or fatal mishaps. At the same time, they are exposed to cosmic rays including high atomic number and energy (HZE) particles such as iron-56 (Fe) ions. Psychological stress or radiation exposure can cause detrimental effects in humans. An earlier published pioneering study showed that chronic restraint-induced psychological stress (CRIPS) could attenuate Trp53 functions and increase carcinogenesis induced by low-linear energy transfer (LET) γ rays in Trp53-heterozygous (Trp53+/-) mice. To elucidate possible modification effects from CRIPS on high-LET HZE particle-induced health consequences, Trp53+/- mice were received both CRIPS and accelerated Fe ion irradiation. Six-week-old Trp53+/- C57BL/6N male mice were restrained 6 h per day for 28 consecutive days. On day 8, they received total-body Fe-particle irradiation (Fe-TBI, 0.1 or 2 Gy). Metaphase chromosome spreads prepared from splenocytes at the end of the 28-day restraint regimen were painted with the fluorescence in situ hybridization (FISH) probes for chromosomes 1 (green), 2 (red) and 3 (yellow). Induction of psychological stress in our experimental model was confirmed by increase in urinary corticosterone level on day 7 of restraint regimen. Regardless of Fe-TBI, CRIPS reduced splenocyte number per spleen at the end of the 28-day restraint regimen. At 2 Gy, Fe-TBI alone induced many aberrant chromosomes and no modifying effect was detected from CRIPS on induction of aberrant chromosomes. Notably, neither Fe-TBI at 0.1 Gy nor CRIPS alone induced any increase in the frequency of aberrant chromosomes, while simultaneous exposure resulted in a significant increase in the frequency of chromosomal exchanges. These findings clearly showed that CRIPS could enhance the frequency of chromosomal exchanges induced by Fe-TBI at a low dose of 0.1 Gy.

Stress and cancer. Part I: Mechanisms mediating the effect of stressors on cancer

Observations indicating a link between psychosocial stress and cancer can be traced back almost 2 millennia. However, the pathways and mechanisms interconnecting them has only been elucidated in more detail since the end of the 20th century. Importantly, recently accumulated evidences have confirmed the ability of stress to promote the induction and progression of cancer. The main aim of this review is to describe the pathways and mechanisms mediating the stimulatory effects of the neuroendocrine stress response on the induction of cancer, potentiation of cancer growth, and the development of metastases.

Multi-Systemic Biological Risk and Cancer Mortality: The NHANES III Study

Multi-systemic biological risk (MSBR), a proxy for allostatic load, is a composite index of biomarkers representing dysregulation due to responses to chronic stress. This study examined the association of an MSBR index with cancer mortality. The sample included n = 13,628 adults aged 20–90 from the NHANES III Linked Mortality File (1988–1994). The MSBR index included autonomic (pulse rate, blood pressure), metabolic (HOMA_ir, triglycerides, waist circumference), and immune (white blood cell count, C-reactive protein) markers. We fit Cox proportional hazards models to estimate hazard ratios (HRs) and 95% confidence intervals (CI) of overall cancer mortality risk, according to quartiles (q) of the index. In multivariable models, compared to those in q1, q4 had a 64% increased risk for cancer mortality (HR = 1.64, 95% CI:1.13–2.40). The immune domain drove the association (HR per unit = 1.19, 95% CI:1.07–1.32). In stratified analyses, the HR for those with a BMI ≥ 25 was 1.12 per unit (95% CI:1.05–1.19) and those with a BMI < 25 was 1.04 per unit (95% CI:0.92–1.18). MSBR is positively associated with risk for cancer mortality in a US sample, particularly among those who are overweight or obese. The utilization of standard clinical measures comprising this index may inform population cancer prevention strategies.

Physical exercise and catecholamines response: benefits and health risk: possible mechanisms

Beneficial effect of regular moderate physical exercise (PE) and negative effect of severe exercise and/or overtraining as an activator of the sympathetic nervous system (SNS) have been shown in numerous aspects of human health, including reduced risk of cardiovascular disease, neurological disease, depression, and some types of cancer. Moderate-to-vigorous PE stimulates the SNS activation, releasing catecholamines (CATs) adrenaline, noradrenaline, dopamine that play an important regulatory and modulatory actions by affecting metabolic processes and the immune system. Summary of the dispersed literature in this area and explanation of the biological mechanisms operating between PE-CATs and the immune system would lead to a better understanding of the beneficial and negative effects of PE on health. This overview aimed to: demonstrate representative literature findings on the exercise released CATs levels, major functions performed by these hormones, their interactions with the immune system and their effects on carbohydrate and lipid metabolism. Also, mechanisms of cytotoxic free radicals and reactive oxygen species (ROS) generation during CATs oxidation, and molecular mechanisms of CATs response to exercise are discussed to demonstrate positive and negative on human health effects. Owing to the large body of the subject literature, we present a representative cross-section of the published studies in this area. The results show a significant role of CATs in carbohydrate and lipid metabolism, immunity and as generators of ROS, depending on PE intensity and duration. Further investigation of the PE-CATs relationship should validate CATs levels to optimize safe intensity and duration of exercise and individualize their prescription, considering CATs to be applied as markers for a dose of exercise. Also, a better understanding of the biological mechanisms is also needed.

Suppression of the innate cancer-killing activity in human granulocytes by stress reaction as a possible mechanism for affecting cancer development

Psychological stress may be linked to cancer incidence; however, more direct evidence is required to support this viewpoint. In this study, we investigated the effects of stress on immunosurveillance against cancer cells using a previously established examination stress model. We showed that the cancer killing activity (CKA) of granulocytes (also known as polymorphic nuclear cells, PMNs) is sharply reduced during examination stress stimulation in some donors who are psychologically sensitive to examination stress, with the concentration of plasma stress hormones (cortisone, epinephrine, and norepinephrine) increasing accordingly. The effects of stress hormones on immune cell CKA were also investigated under two in vitro co-incubation conditions, with all three hormones found to exert inhibitory effects on the CKA of PMNs and mononuclear cells. We showed that stress triggered the release of stress hormones which had profound inhibitory effects on the innate anticancer functions of PMNs. These results provide a possible explanation for the relationship between psychological stress and cancer incidence.

Psychological Stress and Cellular Aging in Cancer: A Meta-Analysis

BACKGROUND

Epidemiological evidence continues to accumulate on the effect of psychosocial and behavioral factors in relation to cancer risk, progression, and mortality.

MATERIAL AND METHODS

This article presents the current evidence on the relationship between psychological stress and the risk of cancer and cellular aging process. Ten databases were searched to identify publications up to September 2019. References from retrieved articles were also reviewed. We included nine review papers and 26 cohort or case-control studies based on inclusion/exclusion criteria.

RESULTS

Results of previously published review articles did not show consistent evidence for the association between cancer risk and psychological stress, while previous evidence is stronger regarding the role of chronic psychological stress on cancer growth and metastasis and aging. In seven observational studies, severe life events, anxiety, depression, insufficient social support perception, or avoiding coping strategy were significantly associated with breast cancer risk. For other specific types of cancer, 11 studies reported increased risk factors for stressful life events, and two others found increased mortality or a decline in treatment adherence.

CONCLUSIONS

Recent epidemiological evidence generally suggests psychosocial factors may be considered risk factors for specific types of cancer and play a key role in the cellular aging process. Understanding molecular mechanisms of the stress interaction is important in cancer management and prevention. The psychological stressors should be considered when developing or evaluating change in psychosocial practice.

Stress and drug resistance in cancer

Patients diagnosed with cancer often undergo considerable psychological distress, and the induction of the psychological stress response has been linked with a poor response to chemotherapy. The psychological stress response is mediated by fluctuations of the hormones glucocorticoids (GCs) and catecholamines. Binding to their respective receptors, GCs and the catecholamines adrenaline/noradrenaline are responsible for signalling a wide range of processes involved in cell survival, cell cycle and immune function. Synthetic GCs are also often prescribed as co-medication alongside chemotherapy, and increasing evidence suggests that GCs may induce chemoresistance in multiple cancer types. In this review, we bring together evidence linking psychological stress hormone signalling with resistance to chemo- and immune therapies, as well as mechanistic evidence regarding the effects of exogenous stress hormones on the efficacy of chemotherapies.

Evaluating the effect of aromatherapy on a stress marker in healthy subjects

Background/purpose

Chemotherapy is important for cancer treatment, but patients' physical and mental stress may lead to unfavorable pain control, an increase in the risk of relapse, and a reduction in the quality of life (QOL). Recently, aromatherapy has been performed in addition to palliative care in many countries, such as Japan and the United States, but scientific evidence remains insufficient. To investigate the usefulness of aromatherapy as complementary and alternative medicine, we evaluated its influence on the immune and autonomic nervous systems.

Methods

We instructed healthy volunteers to inhale aroma oil at bedtime for 6 weeks, and measured changes in the salivary level of secretory immunoglobulin A (s-IgA). Furthermore, blood was collected in addition to saliva in some healthy volunteers, and the blood level of noradrenaline (NA) was measured to examine its relationship to changes in the salivary s-IgA level.

Results

Aromatherapy with lavender and grapefruit oils significantly increased the salivary s-IgA level: lavender oil increased 3.5-fold (p = 0.03), and grapefruit oil increased 2.55-fold (p = 0.04). On lavender oil inhalation, there was a weak, positive correlation between changes in the salivary s-IgA level and those in the blood NA level (R² = 0.24).

Conclusion

The results showed that aromatherapy with lavender and grapefruit oils reduced stress by acting on the immune and autonomic nervous systems in healthy volunteers. In the future, its clinical usefulness must be investigated through similar examination in patients in whom the stress level may be high.

Childhood experiences of parenting and cancer risk at older ages: findings from the English Longitudinal Study of Ageing (ELSA)

Objectives

Despite the importance of childhood experiences for adult health and psychosocial factors for cancer development, parenting, a key childhood psychosocial exposure, has yet to be studied in relation to cancer risk at older ages. We examined whether childhood experiences of poor-quality parenting are associated with an increased risk of cancer at older ages.

Methods

We used a sample of 4471 community dwellers aged ≥ 55 years in 2007. Poor-quality parenting was defined as low levels of parental care and high levels of parental overprotection.

Results

Overall poorer experiences of parenting, decreasing parental care and increasing parental overprotection were associated with increased risk of incident all-site and skin cancer in men, but not in women. Increasing paternal overprotection was also associated with increased risk of incident colorectal cancer in men. Overall poorer experiences of parenting and increasing paternal overprotection were associated with increased risk of prevalent all-site and colorectal cancer in women. Adjustment for covariates explained a small part of these associations.

Conclusions

Older adults who reported childhood experiences of poorer quality parenting appear to have an increased risk of cancer. These findings improve our understanding of the role of psychosocial factors in cancer over the life course.

Electronic supplementary material

The online version of this article (10.1007/s00038-018-1117-3) contains supplementary material, which is available to authorized users.

Cortisol, cortisone, and 4-methoxyphenylacetic acid as potential plasma biomarkers for early detection of non-small cell lung cancer

BACKGROUND

Lung cancer is the most common cause of cancer-related deaths in men and women worldwide. Novel diagnostic biomarkers are urgently required to enable the early detection and treatment of lung cancer, and using novel methods to explore tumor-related biomarkers is a hot topic in lung cancer research. The purpose of this study was to use ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS) metabolomics analysis technology combined with multivariate data processing methods to identify potential plasma biomarkers for non-small cell lung cancer (NSCLC).

METHODS

Plasma samples from 99 NSCLC patients and 112 healthy controls were randomly divided into the screening group and the validation group, respectively. UPLC-MS metabolomics analysis technology combined with multivariate data processing methods were used to identify potential plasma biomarkers for NSCLC.

RESULTS

A total of 254 metabolites were detected and validated in plasma. Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) modeling indicated that 28 endogenous metabolites were present at significantly different levels in patients with NSCLC than healthy controls (variable importance in projection (VIP)>1 and P<0.001 (independent samples t-test) in both the screening group and the validation group). Further analysis revealed that cortisol, cortisone, and 4-methoxyphenylacetic acid had high sensitivity and specificity values as biomarkers for discriminating between NSCLC and healthy controls. Significant associations between specific plasma metabolites and the pathological type or stage of NSCLC were also observed.

CONCLUSIONS

Metabolomics has the potential to distinguish between NSCLC patients and healthy controls, and may reveal new plasma biomarkers for the early detection of NSCLC.

Social support and ovarian cancer incidence - A Swedish prospective population-based study

OBJECTIVE

Low social support is associated with worse prognosis for epithelial ovarian cancer (EOC) patients. However, few studies have explored the relation between low social support and incidence of EOC. The aim of this prospective nested case-control study was to examine whether self-perceived low social support was associated with the incidence of EOC.

METHODS

The Swedish Cancer Registry was used to identify participants in the Västerbotten Intervention Programme (VIP) comprising 58,000 women, who later developed EOC. Each case was matched to four cancer free controls. The VIP uses the Social Support questionnaire, a modified version of the validated questionnaire "The Interview Schedule for Social Interaction" (ISSI) measuring quantitative (AVSI) and qualitative (AVAT) aspects of social support.

RESULTS

The risk of EOC in relation to AVSI and AVAT was similar between the 239 cases and the 941 controls after adjustment for educational level, smoking, BMI, Cambridge Physical Activity Index and age (aOR 0.85, 95% CI 0.72-1.01 and aOR 0.54, 95% CI 0.16-1.81). Lagtime was found to have no impact. A decreased risk of serous ovarian cancer was seen in women with fewer persons available for informal socializing (aOR 0.75, 95% CI 0.59-0.95). Adjusted analyses showed non-significant odds ratios below 1.0 in the vast majority of histotypes.

CONCLUSIONS

A general trend towards a decreased risk of ovarian cancer associated with low AVSI and AVAT was identified. Solely the serous subtype was significantly associated with low scores of AVSI. Prospective pathophysiological and epidemiological studies regarding social support are needed.

Hormonal systems, human social bonding, and affiliation

Which hormones are implicated in human social bonding and affiliation? And how does field research speak to this issue? We begin by laying out a broad view of how endocrine hormones in general modulate life history allocations of energy and other resources, and the ways in which their neuromodulatory functions must be understood within a broader conceptualization of how they have been shaped to affect allocations. We then turn to four specific hormones or hormone families that have received much attention: oxytocin, opioids, prolactin, and progesterone. Each plays a role in regulating psychological capacities and propensities that underlie individuals' interactions with important social targets. Yet in no case is it clear exactly what regulatory roles these hormones play. We suggest several directions for future research.

Effects of chronic restraint-induced stress on radiation-induced chromosomal aberrations in mouse splenocytes

Both ionizing radiation (IR) and psychological stress (PS) cause detrimental effects on humans. A recent study showed that chronic restraint-induced PS (CRIPS) diminished the functions of Trp53 and enhanced radiocarcinogenesis in Trp53-heterozygous (Trp53^+/-) mice. These findings had a marked impact on the academic field as well as the general public, particularly among residents living in areas radioactively contaminated by nuclear accidents. In an attempt to elucidate the modifying effects of CRIPS on radiation-induced health consequences in Trp53 wild-type (Trp53^+/+) animals, investigations involving multidisciplinary analyses were performed. We herein demonstrated that CRIPS induced changes in the frequency of IR-induced chromosomal aberrations (CAs) in splenocytes. Five-week-old male Trp53^+/+ C57BL/6J mice were restrained for 6h per day for 28 consecutive days, and total body irradiation (TBI) at a dose of 4Gy was performed on the 8th day. Metaphase chromosome spreads prepared from splenocytes at the end of the 28-day restraint regimen were painted with fluorescence in situ hybridization (FISH) probes for chromosomes 1, 2, and 3. The results obtained showed that CRIPS alone did not induce CAs, while TBI caused significant increases in CAs, mostly translocations. Translocations appeared at a lower frequency in mice exposed to TBI plus CRIPS than in those exposed to TBI alone. No significant differences were observed in the frequencies of the other types of CAs (insertions, dicentrics, and fragments) visualized with FISH between these experimental groups (TBI+CRIPS vs. TBI). These results suggest that CRIPS does not appear to synergize with the clastogenicity of IR.

Influencing Genomic Change and Cancer Disparities through Neighborhood Chronic Toxic Stress Exposure: A Research Framework

Black Americans have disproportionately higher incidence and mortality rates for many cancers. These disparities may be related to genomic changes that occur from exposure to chronic toxic stress and may result from conditions associated with living in racially segregated neighborhoods with high rates of concentrated poverty. The purpose of this article is to present a nursing research framework for developing and testing neighborhood-level interventions that have the potential to mitigate exposure to neighborhood-associated chronic toxic stress, improve individual-level genomic sequelae and cancer outcomes, and reduce cancer health disparities of Black Americans. Public health nursing researchers should collaborate with local officials to determine ways to reduce neighborhood-level stress. Intermediate outcomes can be measured using genomic or other stress biomarkers, and long-term outcomes can be measured by evaluating population-level cancer incidence and mortality.

Magnesium Supplementation Diminishes Peripheral Blood Lymphocyte DNA Oxidative Damage in Athletes and Sedentary Young Man

Sedentary lifestyle is highly associated with increased risk of cardiovascular disease, obesity, and type 2 diabetes. It is known that regular physical activity has positive effects on health; however several studies have shown that acute and strenuous exercise can induce oxidative stress and lead to DNA damage. As magnesium is essential in maintaining DNA integrity, the aim of this study was to determine whether four-week-long magnesium supplementation in students with sedentary lifestyle and rugby players could prevent or diminish impairment of DNA. By using the comet assay, our study demonstrated that the number of peripheral blood lymphocytes (PBL) with basal endogenous DNA damage is significantly higher in rugby players compared to students with sedentary lifestyle. On the other hand, magnesium supplementation significantly decreased the number of cells with high DNA damage, in the presence of exogenous H₂O₂, in PBL from both students and rugby players, and markedly reduced the number of cells with medium DNA damage in rugby players compared to corresponding control nonsupplemented group. Accordingly, the results of our study suggest that four-week-long magnesium supplementation has marked effects in protecting the DNA from oxidative damage in both rugby players and in young men with sedentary lifestyle. Clinical trial is registered at ANZCTR Trial Id: ACTRN12615001237572.

Adrenergic DNA damage of embryonic pluripotent cells via β2 receptor signalling

Embryonic pluripotent cells are sensitive to genotoxicity though they need more stringent genome integrity to avoid compromising multiple cell lineages and subsequent generations. However it remains unknown whether the cells are susceptible to adrenergic stress which can induce somatic cell genome lesion. We have revealed that adrenergic stress mediators cause DNA damage of the cells through the β2 adrenergic receptor/adenylate cyclase/cAMP/PKA signalling pathway involving an induction of intracellular reactive oxygen species (ROS) accumulation. The adrenergic stress agonists adrenaline, noradrenaline, and isoprenaline caused DNA damage and apoptosis of embryonic stem (ES) cells and embryonal carcinoma stem cells. The effects were mimicked by β2 receptor-coupled signalling molecules and abrogated by selective blockade of β2 receptors and inhibition of the receptor signalling pathway. RNA interference targeting β2 receptors of ES cells conferred the cells the ability to resist the DNA damage and apoptosis. In addition, adrenergic stimulation caused a consistent accumulation of ROS in the cells and the effect was abrogated by β2 receptor blockade; quenching of ROS reversed the induced DNA damage. This finding will improve the understanding of the stem cell regulatory physiology/pathophysiology in an adrenergic receptor subtype signalling mechanism.