The association between stressful life events and breast cancer risk: a meta-analysis

Trait Mindfulness and Social Support Predict Lower Perceived Stress Burden in Patients Undergoing Radiation Therapy

Purpose

Cancer diagnosis and treatment, including radiation therapy (RT), cause significant patient stress. Mindfulness and social support have been shown to help manage the psychological effects of cancer treatment. The objective of our study was to determine the sociodemographic and clinical factors associated with stress burden in patients receiving RT.

Methods and Materials

Patients receiving RT for cancer at a single institution were given a 3-section survey to complete during the first on-treatment visit. The survey included the Perceived Stress Scale, Medical Outcomes Study Social Support Survey, and Mindfulness Attention Awareness Scale, which were used to measure stress, social support, and trait mindfulness, respectively. Linear regression analysis was performed to determine associations between perceived stress and age, patient sex, race and ethnicity, treatment intent, disease site, trait mindfulness, and social support. Factors significant in univariable analysis were analyzed with a multivariable analysis.

Results

A total of 93 patients undergoing RT at a tertiary care academic institution were recruited from July to September 2019. Median scores for Perceived Stress Scale, Medical Outcomes Study Social Support Survey, and Mindfulness Attention Awareness Scale were 14.6 (range, 0-31; SD, 6.9), 4.2 (range, 1-5; SD, 1.0), and 5.1 (range, 3.1-6.0; SD, 0.8), respectively. On univariable analysis, mindfulness and social support were associated with decreased stress burden, and female sex and palliative intent were associated with increased stress burden. These factors all maintained significance in multivariable analysis.

Conclusions

These results suggest measures to improve mindfulness and perceived social support, such as mindfulness meditation and psychoeducational approaches, may lessen the stress burden and improve quality of life for patients undergoing RT. Future studies should analyze the longitudinal impact of individual patient characteristics, including patient sex and treatment intent, to better understand their effects on psychological maladjustment during cancer care.

Mechanisms of stress-attributed breast cancer incidence and progression

Breast cancer is the most commonly diagnosed cancer and the second leading cause of cancer deaths in women, with psychosocial stress commonly cited by patients as one of its causes. While there is conflicting epidemiological evidence investigating the association between psychosocial stress and breast cancer incidence and progression, there is reason to believe that interventions aimed at reducing stress pharmacologically or psychologically may improve breast cancer outcomes. The aim of this review is to discuss the molecular and biological mechanisms of stress-attributed breast cancer incidence and progression, including the induction of the hypothalamic-pituitary-adrenal (HPA) axis and the sympathetic nervous system (SNS), as well as decreased immune function and stress hormone-induced resistance to chemotherapy. Moreover, these mechanisms have been cited as potential therapeutic targets of pharmacologic and psychological interventions that may improve the care, well-being and survival of breast cancer patients. Further research is recommended to investigate whether interventions in the primary care setting for women with risk factors for breast cancer development may lead to a decreased incidence of invasive breast tumors.

β2-Adrenoceptor Activation Favor Acquisition of Tumorigenic Properties in Non-Tumorigenic MCF-10A Breast Epithelial Cells

Noradrenaline and adrenaline, and their cognate receptors, are currently accepted to participate in cancer progression. They may also participate in cancer initiation, although their role in this phase is much less explored. The aim of this work was to study the influence of adrenergic stimulation in several processes related to breast cancer carcinogenesis, using several adrenergic agonists in the MCF-10A non-tumorigenic breast cells. Activation of the β-adrenoceptors promoted an epithelial phenotype in MCF-10A cells, revealed by an increased expression of the epithelial marker E-cadherin and a decrease in the mesenchymal markers, N-cadherin and vimentin. MCF-10A cell motility and migration were also impaired after the β-adrenoceptors activation. Concomitant with this effect, β-adrenoceptors decrease cell protrusions (lamellipodia and filopodia) while increasing cell adhesion. Activation of the β-adrenoceptors also decreases MCF-10A cell proliferation. When the MCF-10A cells were cultured under low attachment conditions, activation the of β- (likely β2) or of α2-adrenoceptors had protective effects against cell death, suggesting a pro-survival role of these adrenoceptors. Overall, our results showed that, in breast cells, adrenoceptor activation (mainly through β-adrenoceptors) may be a risk factor in breast cancer by inducing some cancer hallmarks, providing a mechanistic explanation for the increase in breast cancer incidences that may be associated with conditions that cause massive adrenergic stimulation, such as stress.

Association between allostatic load and breast cancer risk: a cohort study

BACKGROUND

Allostatic load (AL) reflects the collective load of chronic stress during lifetime. Previous studies have shown that higher AL is associated with poor clinical outcomes among breast cancer patients. However, the relationship between AL and breast cancer risk is still unclear.

METHODS

To fill the gap, we analyzed the association between AL and the development of breast cancer in 181,455 women identified from the UK Biobank.

RESULTS

During the follow-up from 2006 to 2020, 5,701 women were diagnosed with incident breast cancer. Significantly higher AL was observed among incident breast cancer cases than all study participants (mean: 2.77 vs. 2.63, P < 0.01). Univariate Cox regression analysis indicated the risk of breast cancer was increased by 5% per one AL unit increase (hazard ratio (HR) = 1.05, 95% confidence interval (CI) 1.04, 1.07). In multivariate analyses, after adjusting demographics, family history of breast cancer, reproductive factors, socioeconomic status, lifestyle factors, and breast cancer polygenic risk score (PRS), the significant association remained (HR = 1.05, 95%CI 1.03, 1.07). The significant relationship was further confirmed in the categorical analysis. Compared with women in the low AL group (AL: 0 ~ 2), those in the high AL group (AL: 3 ~ 11) had a 1.17-fold increased risk of breast cancer (HR = 1.17, 95%CI 1.11, 1.24). Finally, in the stratified analysis, joint effects on the risk of breast cancer were observed between the AL and selected known breast cancer risk factors, including age, family history of breast cancer, PRS, income, physical activity, and alcohol consumption.

CONCLUSION

In summary, those findings have demonstrated that higher AL was associated with an increased breast cancer risk in women. This association is likely independent of known breast cancer risk factors. Thus, the AL could be a valuable biomarker to help breast cancer risk prediction and stratification.

Psychosocial interventions reduce cortisol in breast cancer patients: systematic review and meta-analysis

Introduction

Cancer initiation, progression and recurrence are intricate mechanisms that depend on various components: genetic, psychophysiological, or environmental. Exposure to chronic stress includes fear of recurrence that can affect biological processes that regulate immune and endocrine systems, increase cancer risk, and influence the survival rate. Previous studies show that psychological interventions might influence the level of cortisol that has been extensively used as a biomarker for measuring hypothalamic-pituitary-adrenal axis functioning and body's immunity response. This meta-analysis aimed to provide a quantitative scrutiny of the effect of certain types of psychosocial interventions on cortisol as a neuroendocrine biomarker in saliva or blood and might predict breast cancer (BC) progression.

Methods

A literature search was performed in the following databases: PubMed, The Cohrane Library, Scopus, WOS, PsychInfo, Google Scholar, Ovid Science Direct. After methodical selection of originally generated 2.021 studies, the search yielded eight articles that met inclusion criteria. All these studies explored effects of psychosocial interventions that measured cortisol in total of 366 participants with BC, stages 0-IV, in randomized control trial or quasi experimental study design setting. We applied random effects model to conduct meta-analyses on the parameters of salivary and plasma cortisol and used PRISMA Guidelines as validated methodology of investigation to report the results.

Results

Eight studies selected for meta-analysis have shown the reduction of cortisol level due to applied psychosocial intervention. The random effects model showed that interventions produced large effect sizes in reductions of cortisol in blood (Cohen's d = -1.82, 95% Confidence Interval (CI): -3.03, -0.60) and slightly less in saliva (d = -1.73, 95%CI: -2.68, -0.78) with an overall effect of d = -1.76 (95%CI: -2.46, -1.07).

Conclusion

Our study concluded that certain types of psychosocial interventions reduce cortisol (indicator of chronic stress) in patients with BC. Application of specific psychosocial support as adjuvant non-invasive therapy for affected females with BC at all phases of treatment could contribute to more cost-effective health care.

Psychological Stress Is Associated with Increased Cancer Risk in Dogs

Although there is evidence that psychological stress may be associated with increased cancer risk, the effect of stress on cancer risk is difficult to study, both in humans, due to socioeconomic factors, and in animal models, due to questionable biological relevance. Here, we test whether heritable canine temperament that increases psychological stress is associated with cancer risk. The study data are breed-specific averages of incidences of multiple cancer types and of temperament classes. The latter are derived from a latent class analysis of behavioral questionnaires completed by owners (C-BARQ). We thus classified the dogs according to whether they are calm vs. reactive within and across breeds. Using meta-analysis approaches, we modeled the risk of multiple cancer types in calm vs. reactive dogs. We adjusted for breed averages of body mass and lifespan, which are common confounders that impact cancer. Our study confirms that body size has a significant effect of on risk of multiple types of cancers in dogs and shows for the first time that temperament also has a moderate effect. These findings suggest dog models of heritable psychological stress are suitable for molecular epidemiological and translational studies on its effects on cancer risk.

Stressful Life Events, Social Support, and Incident Breast Cancer by Estrogen Receptor Status

Chronic stress affects immune function and hormonal signaling and has been hypothesized to be associated with breast cancer, although results from the few prior studies are mixed and have not examined potential differences by estrogen receptor (ER) status. Using the Women's Health Initiative study, we included 76,951 postmenopausal women followed for events for a median of 16.7 years to investigate the association between baseline self-reported stressful life events and incident breast cancer by ER status and whether the association was modified by social support. We generated Cox proportional hazards models adjusting for demographic, clinical, lifestyle/behavioral, and social factors to estimate HRs and 95% confidence intervals (95%CI). The mean age was 63 (SD, 7.3), and majority of participants were White race (83.5%) and married or in a marriage-like relationship (63.0%). In analyses stratified by ER status, there was no relationship between stressful life events and ER-positive breast cancer. In contrast, compared with women in the lowest quartile, those in higher quartiles had an increased risk of ER-negative breast cancer, where those in quartile 4 had the highest risk (Quartile 4 vs. Quartile 1; HR = 1.30; 95%CI, 1.01-1.68; Ptrend = 0.050). Moreover, associations were stronger for the highest versus lowest quartile of stressful life events among widowed women (HR = 2.39; 95%CI, 1.29-4.44; Pinteraction<0.001). Association between stressful life events and ER-negative breast cancer was not modified by social support. In this cohort of postmenopausal women, higher experiences of prediagnostic stressful life events were associated with increased risk of ER-negative breast cancer.

PREVENTION RELEVANCE

Epidemiologic studies on the association between psychosocial stress and breast cancer risk remain inconsistent, while investigation of whether the association differs by ER status is limited. In this prospective cohort of postmenopausal women, high experiences of stressful life events were positively associated with ER-negative disease but not ER-positive.

Cancer Incidence in Korean Healthcare Workers in Hospitals

Objectives: Healthcare workers in hospitals (HHCWs), a notably increasing workforce, face various occupational hazards. A high incidence of cancer among HHCWs has been observed; however, the cancer incidence status among HHCWs in South Korea is yet to be studied. This study aimed to assess cancer incidence among HHCWs in South Korea. Methods: We constructed a retrospective cohort of HHCWs using National Health Insurance claims data, including cancer incidence status and vital status, from 2007 to 2015. Those who had worked in hospitals for at least three years were defined as HHCWs. Standardized incidence ratios (SIRs) for all cancer types and standardized mortality ratios were calculated. Results: A total of 107,646 HHCWs were followed up, and the total follow-up duration was 905,503 person-years. Compared to the total workers, female HHCWs showed significantly higher SIR for all cancers (observed cases = 1480; SIR = 1.25; 95% confidence interval [CI] = 1.06–1.47). The incidence of breast cancer among female HHCWs was significantly higher compared to that among total workers (observed cases = 376; SIR = 1.21; 95% CI = 1.09–1.36). Conclusions: Our findings indicate that female HHCWs have an elevated probability of developing cancer, which suggests that occupational risk factors such as night-shift work, anti-neoplastic medications, stressful jobs, and ionizing radiation should be assessed. Further investigation and occupational environment improvement activities are required.

Association between WHO First-Step Analgesic Use and Risk of Breast Cancer in Women of Working Age

We assessed the association between breast cancer and analgesic use in women of a specific working-age group. The Korean National Health Insurance Service-National Sample Cohort database (KNHIS-NSC) data were analyzed. We calculated hazard ratios (HRs) with 95% confidence intervals (CIs) for patients' cancer risk based on whether the women participated in economic activity (PEA or not PEA (NPEA) groups) and analgesic use. Additionally, breast cancer incidence variations by age group, and PEA or NPEAs, health behavior, Charlson Comorbidity Index, and analgesic use were evaluated. The PEA group had a higher cancer risk than the NPEA group (HR = 1.542, 95% CI: 1.345-1.768, p < 0.001). Breast cancer risk was high in the PEA, high income, and no history of exercise groups, but significantly reduced in the regular-use-of-analgesics group. Notably, the working age group of 40~49 years, within the PEA group, had the highest HR of breast cancer development (HR = 1.700, 95% CI = 1.361-2.124, p < 0.001); whereas regular analgesic use in those aged 25~39 years decreased breast cancer risk (HR = 0.611, 95% CI = 0.427-0.875, p < 0.05). In conclusion, our results suggest that individuals at a high-risk of comorbidity may benefit from regular use of analgesics, which may prove to be a useful strategy for breast cancer prevention in the Young-aged group.

Psychological Distress in Breast Cancer Patients during the Italian COVID-19 Pandemic

BACKGROUND

The emergency caused by the SARS-CoV-2 pandemic exacerbated psychological distress. Our aim was to investigate the impact of breast cancer on patients' lives during the Italian lockdown.

METHODS

Sixty-five female breast cancer patients were studied, assessing the level of psychological distress with the Hospital Anxiety and Depression Scale (HADS) and the impact of the cancer diagnosis (Impact of Event Scale-Revised-IES-R). In addition, we compared these data with a matched group of breast cancer patients enrolled in 2019.

RESULTS

Patients enrolled in 2020 had statistically higher levels of anxious symptomatology and higher levels of traumatic symptomatology due to the cancer diagnosis. A mediation analysis was performed to determine how the experience of distress due to COVID-19 negatively impacted the level of anxiety and amplified the impact of the diagnosis with a significant increase in traumatic symptoms.

CONCLUSIONS

Considering the vulnerability of these patients and the serious and novel situation that the healthcare system is currently facing, we would like to point out the importance of structured and organised psychological support for these patients.

Association of Allostatic Load and All Cancer Risk in the SWAN Cohort

Elevated chronic stress is thought to increase cancer risk, though the results so far have been inconsistent. In this study, we assessed the relationship between allostatic load (AL), a biological indicator of chronic stress, and overall cancer risk in 3015 women who participated in the Study of Women’s Health Across the Nation (SWAN). Based on the distribution of AL, the study population was categorized into four groups, from the lowest (1st category) to the highest AL group (4th category). At baseline, African American and Hispanic women were more likely to be in the higher AL categories than White women (p < 0.001). In addition, women who smoked regularly, drank alcohol regularly, had no leisure physical activity, and had restless sleep were also more likely to be in the higher AL categories than their relative counterparts (p < 0.001). We also observed that women in the lower-income category with no health insurance were more likely to be in the higher AL category (p < 0.001). The study then found that women in the 4th category of AL (the highest AL group) had a 1.64-fold increased risk of overall cancer (Hazard ratio (HR): 1.64, 95% confidence interval (CI): 1.04, 2.59). The risk association was further strengthened after adjusting demographics, healthy behaviors, and socioeconomic factors with an HR of 2.08. In further analysis of individual biomarkers of AL score, we found that higher levels of triglyceride and CRP were associated with increased risk of cancer, highlighting the role of metabolic dysfunction and inflammation in the etiology of cancer development. In summary, we report that higher AL is associated with increased cancer risk.

Influence of Psychological Factors in Breast and Lung Cancer Risk - A Systematic Review

Introduction: In 2020, according to the Global Cancer Observatory, nearly 10 million people died of cancer. Amongst all cancers, breast cancer had the highest number of new cases and lung cancer had the highest number of deaths. Even though the literatures suggest a possible connection between psychological factors and cancer risk, their association throughout studies remains inconclusive. The present systematic review studied the connection between psychological factors and the risk of breast and lung cancer, prior to a cancer diagnosis. The psychological factors of trauma, grief, and depression were studied. Methods: The current systematic review was carried out across multiple databases in two phases, an initial exploratory research in June 2020, refined with a second electronic research in December 2020. The inclusion criteria included studies describing the association between trauma, posttraumatic stress disorder (PTSD), grief, and depression with breast and lung cancer risk. The psychological data collection must have been carried out prior to a confirmed breast or lung cancer diagnosis, and accessed through self-report measures, questionnaires, clinical interviews, or clinical diagnoses. Study reports had to contain information about the incidence of cancer and effect size. The exclusion criteria were studies in which psychological factors were collected after cancer diagnosis. Results and Conclusion: A total of 26 studies were included. Although non-consensual, the findings from the present systematic review suggest that, in addition to the known risk factors, psychological factors may play an important role in the etiology of both breast and lung cancer. To include psychological factors as a variable that affects cancer development may be fundamental to opening new avenues for prevention and intervention. Systematic Review Registration: [www.ClinicalTrials.gov], identifier [CRD42020209161].

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

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

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.

Causal Attributions in Breast Cancer Patients Planning to Undergo Adjuvant Endocrine Therapy

The aim of this study was to explore causal attributions among Korean breast cancer patients who were planning to undergo adjuvant endocrine therapy (AET) as well as the relationships between patient demographic and clinical characteristics and their causal attributions. Causal attributions were assessed with an open-ended response item, which asked patients to list what they thought were the three most important causal factors of their illness. The relationships between patient characteristics and causal attributions were determined through univariate analysis, and the relationships between causal attributions were obtained using social network analysis. A total of 299 participants provided 707 responses. Stress, diet, and exercise were believed to be the three most likely causes of breast cancer. There were no significant differences between causal attributions and the age, education level, marital status, or cancer stage of patients. However, there were differences in the associations between personality, genetics, and reproductive history and patient-identified causal attributions according to the patients' family history of cancer. Patients with a family history of cancer were more likely to believe that personality and genetics/family history were causes of breast cancer compared to patients without such a history. Therefore, it is necessary to educate patients to perceive stress and lifestyle-related factors as modifiable causal factors in order to have a positive effect on their adherence to AET.

Genetic Variation and Immunohistochemical Localization of the Glucocorticoid Receptor in Breast Cancer Cases from the Breast Cancer Care in Chicago Cohort

BACKGROUND

Glucocorticoid, one of the primary mediators of stress, acts via its receptor, the glucocorticoid receptor (GCR/NR3C1), to regulate a myriad of physiological processes. We measured the genetic variation and protein expression of GCR, and the genes that regulate GCR function or response and examined whether these alterations were associated with breast cancer clinicopathological characteristics.

METHOD

We used samples from a multiracial cohort of breast cancer patients to assess the association between breast cancer characteristics and the genetic variants of single nucleotide polymorphisms (SNPs) in GCR/NR3C1, FKBP5, Sgk1, IL-6, ADIPOQ, LEPR, SOD2, CAT, and BCL2.

RESULTS

Several SNPs were associated with breast cancer characteristics, but statistical significance was lost after adjustment for multiple comparisons. GCR was detected in all normal breast tissues and was predominantly located in the nuclei of the myoepithelial cell layer, whereas the luminal layer was negative for GCR. GCR expression was significantly decreased in all breast cancer tissue types, compared to nontumor tissue, but was not associated with breast cancer characteristics. We found that high nuclear GCR expression was associated with basal cell marker cytokeratin 5/6 positivity.

CONCLUSION

GCR expression is reduced in breast cancer tissue and correlates with the basal cell marker CK5/6.

The Role of Stress in Breast Cancer Incidence: Risk Factors, Interventions, and Directions for the Future

Stress is a common belief among breast cancer patients and the public to explain variation in breast cancer incidence. Epidemiological studies interrogating the relationship between stress and cancer have reported mixed results. The impact of the topic and the lack of consensus has sparked this review of the literature to investigate gaps in knowledge and identify areas of research. We first present a brief summary of the biopsychosocial model generally used to conduct research on stress. We then divide the overview of the literature into areas of research focus. These include the role of distressing life events in breast cancer incidence, the role of adverse childhood events in later breast cancer incidence, the importance of race and socioeconomic status (SES) as social determinants of breast cancer incidence, and the specific role of chronic stress in relation to breast cancer. For each topic, we discuss the potential of stress as a risk factor and possible intervention strategies that could reduce the effects of stress. We then identify further research questions to be probed to fill the gaps in knowledge. We conclude with a discussion of future research directions for stress research as it relates to breast cancer incidence.

Plasma glucocorticogenic activity, race/ethnicity and alcohol intake among San Francisco Bay Area women

Racial and ethnic minorities are at higher risk for a variety of diseases. While sociodemographic and lifestyle factors contribute to racial/ethnic health disparities, the biological processes underlying these associations remain poorly understood. Stress and its biological consequences through the glucocorticoid receptor (GR) have been hypothesized to mediate adverse disease outcomes. In fasting morning samples of 503 control women from the San Francisco Bay Area Breast Cancer Study, we used a sensitive Chemical-Activated LUciferase gene eXpression (CALUX) assay to examine the association of sociodemographic and lifestyle factors with plasma glucocorticogenic (G) activity in three racial/ethnic groups. The G activity is a sensitive measure that reflects biological activity of total plasma glucocorticoids including cortisol and glucocorticoid-like compounds. Associations between G activity and sociodemographic and lifestyle factors were examined using multivariable linear regression models. Latina and non-Latina Black (NLB) women had 9% (P = 0.053) and 14% (P = 0.008) lower morning G activity than non-Latina White (NLW) women, respectively. Additionally, we replicated a previously reported association between G activity and alcohol intake (women who drank >10gms had 19% higher G activity than non-drinkers, P = 0.004) in Latina and NLB women. Further research should assess the association between G activity and health outcomes in a prospective cohort so as to characterize the relationship between total plasma G activity in pre-disease state and disease outcomes across different racial/ethnic populations.

β-Adrenergic Signaling in Lung Cancer: A Potential Role for Beta-Blockers

Lung cancer results in more patient deaths each year than any other cancer type. Additional treatment strategies are needed to improve clinical responses to approved treatment modalities and prevent the emergence of resistant disease. Catecholamines including norepinephrine and epinephrine are elevated as a result of chronic stress and mediate their physiological effects through activation of adrenergic receptors on target tissues. Lung cancer cells express β-adrenergic receptors (β-ARs), and numerous preclinical studies indicate that β2-AR signaling on lung cancer cells facilities cellular programs including proliferation, motility, apoptosis resistance, epithelial-to-mesenchymal transition, metastasis, and the acquisition of an angiogenic and immunosuppressive phenotype. Here, we review the preclinical and clinical evidence supporting a potential role for beta-blockers in improving the clinical outcome of lung cancer patients. Graphical Abstract Catecholamines including norepinephrine and epinephrine act of β-ARs expressed on NSCLC tumor cells and activate pathways regulating tumor progression.

Risk Factors of Breast Cancer in Hadramout Valley and Desert, Yemen

BACKGROUND

The incidence of breast cancer is on rise in low- and middle-income countries as populations increasingly adopt western lifestyles. Studies on risk factors of cancers including breast cancer are lacking in Yemen. Therefore, this study aimed to determine the risk factors of breast cancer among women registered at Hadramout Valley and Desert Oncology Center (HVDOC).

METHODS

A case-control study was conducted at HVDOC, Yemen. All women who were registered in HVDOC and diagnosed with breast cancer and confirmed by histopathology during 2011-2015 were selected as cases. Age-matched controls were selected from women who underwent mammography in HVDOC during 2011-2015 and were confirmed to be free of breast cancer. Data were collected using semi-structured questionnaire and clinical data were abstracted from the medical records.

RESULTS

A total of 105 patients and 210 controls were included in this study. About 70.5% of cases and 72.4% of control were 50 years old or younger. Compared with married women, divorced women had higher odds of breast cancer [odds ratio (OR) = 2.2]. The odds of breast cancer was higher for women who had never breastfed a child (OR = 1.7). Having hypertension (OR = 2.5), family history of malignancy (OR = 2.4), and postmenopausal status (OR = 2.0) were significantly associated with higher odds of breast cancer in multivariate analysis.

CONCLUSIONS

The main risk factors for breast cancer among women in Yemen are divorced marital status, never breastfed a child, having hypertension, family history of malignancy, and postmenopause. Regular screening especially among women with high risk is needed.

Stress, inflammation, and eicosanoids: an emerging perspective

Clinical and experimental studies support the notion that adrenergic stimulation and chronic stress affect inflammation, metabolism, and tumor growth. Eicosanoids are also known to heavily influence inflammation while regulating certain stress responses. However, additional work is needed to understand the full extent of interactions between the stress-related pathways and eicosanoids. Here, we review the potential influences that stress, inflammation, and metabolic pathways have on each other, in the context of eicosanoids. Understanding the intricacies of such interactions could provide insights on how systemic metabolic effects mediated by the stress pathways can be translated into therapies for cancer and other diseases.

The association between life satisfaction, vitality, self-rated health, and risk of cancer

PURPOSE

Only few prospective studies have been conducted on the contribution of quality of life-related factors to the risk of cancer. The aim of this study was to investigate the prospective associations of three quality of life-related factors with the risk of cancer; life satisfaction, vitality, and self-rated health.

METHODS

In 2009-2011, 7189 participants in the Copenhagen Aging and Midlife Biobank were asked to rate their life satisfaction, their vitality, and their health. The study population was followed until the end of 2015 for registration of cancer in the Danish National Patient Register.

RESULTS

During the follow-up period, cancer was diagnosed in 312 individuals. Life satisfaction was not associated with the risk of cancer. Vitality was significantly associated with the risk of cancer, but the association became non-significant after adjustment for age, sex, socioeconomic position, and lifestyle factors. However, when additionally adjusting for life satisfaction, individuals who rated their vitality as low had a hazard ratio of 1.46 (95% confidence interval [CI] 1.04-2.07) for the development of cancer. Individuals who rated their health as poor had a hazard ratio of 1.70 (95% CI 1.27-2.26) for the development of cancer, compared with individuals with good, very good, or excellent self-rated health. The association remained significant after adjustment for basic confounders, life satisfaction, and vitality.

CONCLUSION

A better grasp of the significance of quality of life-related factors for the risk of cancer may be of great importance to population-based cancer prevention that aims to target early risk factors for development of cancer across widespread cancer sites.

Psychosocial stress is associated with benign breast disease in young Chinese women: results from Project ELEFANT

PURPOSE

Psychosocial stress, including bereavement and work-related stress, is associated with the risk of breast cancer. However, it is unknown whether it may also be linked with increased risk of benign breast disease (BBD).

METHODS

Our study leveraged 61,907 women aged 17-55 years old from the Project ELEFANT study. BBD was diagnosed by clinician. Self-reported data on psychosocial stress over a 10-year period was retrospectively collected from questionnaires and categorised by cause (work, social and economic) and severity (none, low and high). Odd ratios (ORs) for the development of BBD were estimated using logistic regression. The model was adjusted for age, BMI, TSH levels, smoking, alcohol consumption, family history, age of menarche, oral contraceptive usage, education and occupation.

RESULTS

Within our study, 8% (4,914) of participants were diagnosed with BBD. Work-related stress [OR 1.57, 95% confidence interval (CI) 1.46-1.69] and financial stress (OR 1.34, 95% CI 1.24-1.44) were significantly associated with BBD incidence, with a smaller but still significant association with social stress (OR 1.11, 95% CI 1.01-1.21). The associations remained significant after exclusion of participants with first- and second-degree family history of breast disease. The presence of multiple forms of stress did not synergistically increase risk. The neutrophil-lymphocyte ratio (NLR), a marker of systemic inflammation and prognostic marker for breast cancer, was not associated with BBD.

CONCLUSIONS

Psychosocial stress, particularly work-related and financial stress, is associated with increased risk of benign breast disease among young Chinese women.

Glucocorticoids promote transition of ductal carcinoma in situ to invasive ductal carcinoma by inducing myoepithelial cell apoptosis

BACKGROUND

The microenvironment and stress factors like glucocorticoids have a strong influence on breast cancer progression but their role in the first stages of breast cancer and, particularly, in myoepithelial cell regulation remains unclear. Consequently, we investigated the role of glucocorticoids in ductal carcinoma in situ (DCIS) in breast cancer, focusing specially on myoepithelial cells.

METHODS

To clarify the role of glucocorticoids at breast cancer onset, we evaluated the effects of cortisol and corticosterone on epithelial and myoepithelial cells using 2D and 3D in vitro and in vivo approaches and human samples.

RESULTS

Glucocorticoids induce a reduction in laminin levels and favour the disruption of the basement membrane by promotion of myoepithelial cell apoptosis in vitro. In an in vivo stress murine model, increased corticosterone levels fostered the transition from DCIS to invasive ductal carcinoma (IDC) via myoepithelial cell apoptosis and disappearance of the basement membrane. RU486 is able to partially block the effects of cortisol in vitro and in vivo. We found that myoepithelial cell apoptosis is more frequent in patients with DCIS+IDC than in patients with DCIS.

CONCLUSIONS

Our findings show that physiological stress, through increased glucocorticoid blood levels, promotes the transition from DCIS to IDC, particularly by inducing myoepithelial cell apoptosis. Since this would be a prerequisite for invasive features in patients with DCIS breast cancer, its clinical management could help to prevent breast cancer progression to IDC.

Possible role of stress, coping strategies, and life style in the development of breast cancer

Objective The aim of the present study was to investigate the possibility of the effect of life long stressful events, along with coping method used, perception of social support, and life style on the development of breast cancer. Methods In this hospital-based case control study, the study group comprised 250 women with breast cancer who were followed by Florence Nightingale Breast Study Group. Control group included 250 women, who had similar sociodemographic characteristics to the study group. Data were collected with semi-structured interview form, Healthy Life Style Behavior Scale, Coping Strategy Indicator, and Stress Evaluation Form developed by us. Results In multivariate analysis, family history of cancer (OR: 1.55, 95% CI: 2.29-1.05), inadequate social support (OR: 1.83, 95% CI: 1.23-2.73), and loss of father during childhood (OR: 2.68, 95% CI: 5.52-1.30) and serious stressor within the last five years (OR: 4.72, 95% CI: 7.03-3.18) were found to be risk factors increasing the risk of breast cancer. When family history of cancer was excluded from the model, the presence of psychiatric disorder history (OR: 1.95, 95% CI: 3.26-1.17) and major life events (OR: 2.24, 95% CI: 4.07-1.24) were added to the model as risk factors. Conclusion The present study indicates that especially the stressful events experienced within the last five years plays an undeniable role in the risk of breast cancer. Social support may be as important in the period before the diagnosis as in the period after diagnosis.

Physical Symptom Burden and Its Association With Distress, Anxiety, and Depression in Breast Cancer

BACKGROUND

Physical symptom burden and psychologic symptoms are highly prevalent in women with breast cancer. The Distress Thermometer and Problem List (DT&PL) is commonly used in oncology clinics to screen for distress and its accompanying Physical Problem List (PPL) identifies pertinent physical symptoms.

OBJECTIVE

We sought to identify physical symptoms found on the PPL and evaluate whether they are associated with psychologic symptoms in women with breast cancer.

METHODS

Patients (n=125) with breast cancer (Stage 0-IV) completed the DT&PL and the Hospital Anxiety and Depression Scale. They reported bother from any of 22 PPL items on the DT&PL. PPL items were assessed for their associations with distress, Hospital Anxiety and Depression Scale-anxiety, and Hospital Anxiety and Depression Scale-depression. The total number of PPL items endorsed per patient was evaluated for associations with psychologic outcomes, controlling for relevant demographic factors.

RESULTS

Most physical problems were associated with depression (n = 13, 87%), and anxiety (n = 8, 53%), but fewer were associated with distress (n = 4, 27%). In multivariate analyses, a higher total number of problems was associated with younger age (p = 0.03) and more depressive symptoms (p < 0.001).

CONCLUSION

Physical symptom burden detected by the DT&PL co-occurs with depression most commonly and to a lesser extent anxiety and distress in women with breast cancer. Depression is associated with more types of physical symptoms and a total number of physical symptoms. The endorsement of multiple PPL items on the DT&PL should prompt an evaluation for depression. Similarly, depression should prompt the evaluation and treatment of physical symptom burden.

Depression in Women with Breast Cancer: A Systematic Review of Cross-Sectional Studies in Iran

Objective: Breast cancer is one of the most common cancers in women and has more severe mental and emotional effects than other types. Depression as a mental disorder affects people’s mental well-being, physical symptoms, occupational performance, and finally quality of life. The aim of this study was to determine depression levels in Iranian women with breast cancer. Methods: A systematic review study was conducted in 2017. English and Persian databases (PubMed, SCOPUS, Web of Science, Google Scholar, SID, Magiran) were searched with key words such as Depression Or Depressive Disorders AND Women AND Breast Cancer OR Tumor OR Neoplasm OR Malignancy AND Iran. Inclusion criteria allowed for cross-sectional studies conducted in Iran (published in English or Persian language journals), studies that had key words in their keywords or their titles and standard instruments for measuring depression in patients. Of the 160 publications found, eight were selected after reviewing the title, abstract and full article. Results: Age of women with breast cancer in selected studies ranged from 43.8 (SD = 47.1) to 55.9 (SD = 14.6) years. Duration of cancer in most studies was about 1-2 years. In most studies, mild levels of depression for women with breast cancer were present. However, in one study it was stated that 69.4% of participants had serious levels of depression. Conclusions: There is increase in the risk of depression in women with breast cancer. Therefore, it seems necessary to plan preventive and therapeutic measures in order to improve the mental health and quality of life of the affected patients.

Psychological stress and breast cancer incidence: a systematic review

Objective

Breast cancer is the world’s leading cause of cancer mortality in women. Stress is an imminent risk factor with a documented negative impact on neuro-endocrine and immune system. Numerous epidemiological studies have investigated the link between stress and cancer, reporting contradictory results from no association to a close causal link. The impact of the topic and the lack of conclusion compelled this systematic review.

Methods

A systematic review was carried out, including all literature studies from 1966 to 2016, investigating the relationship between stress and the occurrence of breast cancer. Of the 1813 articles identified in the PubMed/Medline database, 52 were eligible and included in the analysis.

Results

A number of 17 retrospective, 20 limited prospective and 15 prospective studies were analyzed. The number of patients exceeded 29,000, for a total number of more than 700.000 women recruited from hospital, screening cohorts or population registers. We identified 26 positive articles linking personal traits, stressful events and breast cancer, 18 negative articles that did not confirm their hypothesis and 8 articles that could not be classified. Facing heterogeneity, all possible misguiding factors such as: study design, information gathering, stress type, moment of exposure, individual susceptibility and personality, were discussed independently.

Conclusions

Qualitative analysis of articles has revealed a possible association between stress and cancer, especially regarding stressful life events. In the absence of a meta-analysis and taking into account the methodological heterogeneity of the studies, the results are difficult to interpret and the role of chance is difficult to exclude.

Perceived stress level and risk of cancer incidence in a Japanese population: the Japan Public Health Center (JPHC)-based Prospective Study

Evidence regarding stress as a risk factor for cancer onset is inconsistent. In this study, based on the Japan Public Health Center-based Prospective Study, we enrolled 101,708 participants aged 40-69 years from 1990-1994. The self-reported perceived stress level was collected at baseline and updated through 5-year follow-up. The association between perceived stress and cancer risk was measured by Cox proportional hazards regression model, adjusted for all known confounders. During follow-up (mean = 17.8 years), we identified 17,161 cancer cases. We found no association between baseline perceived stress level and cancer incidence. However, by taking account of the dynamic changes in perceived stress, time-varying analyses revealed a slightly (4-6%) increased overall cancer risk for subjects under elevated perceived stress levels compared to the 'low stress level' group. Analyses concerning long-term perceived stress level showed that individuals with constantly high perceived stress level had an 11% (95% confidence interval 1-22%) excess risk for cancer compared to subjects with persistently low stress levels. This association was confined to men (20% excess risk), and was particularly strong among smokers, alcohol drinkers, obese subjects, and subjects without family history of cancer. Therefore, we concluded high perceived stress level might contribute to excess overall cancer incidence among men.

Roles of Biopsychosocial Factors in the Development of Breast Cancer

OBJECTIVE

The aim of this study was to determine the roles of biopsychosocial risk factors in the development of breast cancer.

MATERIALS AND METHODS

This hospital-based case-control study included 491 women with breast cancer (study group) and 512 women who did not have cancer or other serious diseases (control group). Biological, psychological, and social risk factors were compared between the two groups. Data were collected using the semi-structured interview, the Stress Assessment Form, and the Coping Strategy Indicator to assess these factors.

RESULTS

When the significantly different biopsychosocial variables between the study and the control groups were evaluated together, independent breast cancer risk factors were found as follows: a stressor experienced in the last 5 years, age 40 years and older, inadequate social support perception, use of avoidance coping strategy, being a housewife, having a family history of cancer, and having a body mass index ≥25.

CONCLUSION

This study showed a relationship between breast cancer risk and manageable variables (obesity, stressor and coping strategy, social support, and employment status), age and family history of cancer, which are biopsychosocial factors. Biopsychosocial aspects are becoming a greater part of many different healthcare systems.

Cancer Prevention During Early Adulthood: Highlights From a Meeting of Experts

Using a life course approach, the Centers for Disease Control and Prevention's Division of Cancer Prevention and Control and the National Association of Chronic Disease Directors co-hosted a 2-day meeting with 15 multidisciplinary experts to consider evidence linking factors in early adulthood to subsequent cancer risk and strategies for putting that evidence into practice to reduce cancer incidence. This paper provides an overview of key themes from those meeting discussions, drawing attention to the influence that early adulthood can have on lifetime cancer risk and potential strategies for intervention during this phase of life. A number of social, behavioral, and environmental factors during early adulthood influence cancer risk, including dietary patterns, physical inactivity, medical conditions (e.g., obesity, diabetes, viral infections), circadian rhythm disruption, chronic stress, and targeted marketing of cancer-causing products (e.g., tobacco, alcohol). Suggestions for translating research into practice are framed in the context of the four strategic directions of the National Prevention Strategy: building healthy and safe community environments; expanding quality preventive services in clinical and community settings; empowering people to make healthy choices; and eliminating health disparities. Promising strategies for prevention among young adults include collaborating with a variety of community sectors as well as mobilizing young adults to serve as advocates for change. Young adults are a heterogeneous demographic group, and targeted efforts are needed to address the unique needs of population subgroups that are often underserved and under-represented in research studies.

Impact of stressful death or divorce in people with HIV: A prospective examination and the buffering effects of religious coping and social support

This study examined the impact of a stressful death/divorce on psychological and immune outcomes in people with HIV. People with HIV with stressful death/divorce were examined from before the event to up to 12 months later (n = 45); controls were assessed at similar intervals (n = 112). Stressful deaths/divorces were associated with increased viral load and anxiety over time (ps ≤ .014), but not CD4+ or depression. Increased use of religious coping after the stressful death/divorce was associated with slower increases in viral load (p = .010). These data suggest people with HIV should consider the potentially elevated risk of transmission after such events and seek appropriate monitoring and care.

The Vietnamese version of the Perceived Stress Scale (PSS-10): Translation equivalence and psychometric properties among older women

BACKGROUND

The Perceived Stress Scale 10 item (PSS-10) has been translated into more than 20 languages and used widely in different populations. Yet, to date, no study has tested psychometric properties of the instrument among older women and there is no Vietnamese version of the instrument.

METHODS

This study translated the PSS-10 into Vietnamese and assessed Vietnamese version of the Perceived Stress Scale 10 items (V-PSS-10) for translation equivalence, face validity, construct validity, correlations, internal consistency reliability, and test-retest reliability among 473 women aged 60 and over.

RESULTS

The study found that V-PSS-10 retained the original meaning and was understood by Vietnamese older women. An exploratory factor analysis of the V-PSS-10 yielded a two-factor structure, and these two factors were significantly correlated (0.56, p < .01) with all item loadings exceeded .50. The V-PSS-10 score was positively correlated with general sleep disturbance (ρ = .12, p < .05), CES-D score for depression symptoms (ρ = .60, p < .01), and negatively correlated with mental (ρ = -.46, p < .01), and physical health scores (ρ = -.19, p < .01). The Cronbach's alpha for the V-PSS-10 was .80, and the test-retest correlation at one month's interval was .43.

CONCLUSION

Findings from this study suggest that the V-PSS-10 has acceptable validity and reliability levels among older women. The V-PSS-10 can be used to measure perceived stress in future research and practice. However, future research would be useful to further endorse the validity and reliability of the V-PSS-10.

Biobehavioral approaches to cancer progression and survival: Mechanisms and interventions

Over the last decade, there have been groundbreaking strides in our understanding of the multiple biological pathways by which psychosocial and behavioral factors can affect cancer progression. It is now clear that biobehavioral factors not only affect cellular immunity but both directly and indirectly modulate fundamental processes in cancer growth, including inflammation, angiogenesis, invasion, and metastasis. There is also an emerging understanding of how psychological and behavioral factors used in interventions can impact these physiological processes. This review outlines our current understanding of the physiological mechanisms by which psychological, social, and behavioral processes can affect cancer progression. The intervention literature is discussed, along with recommendations for future research to move the field of biobehavioral oncology forward.

The influence of personality and perceived stress on the development of breast cancer: 20-year follow-up of 29,098 Japanese women

Breast cancer is the most common cancer in women. However, it remains unproven whether psychological factors have an influence on breast cancer incidence. In our earlier study, subjects possessing two personality traits, decisiveness and "ikigai" (a Japanese word meaning something that makes one's life worth living), showed a significantly lower risk of developing breast cancer, although no psychological factors have been convincingly demonstrated to have an influence on breast cancer development in other studies. Therefore, we conducted this follow-up analysis to confirm the association between breast cancer incidence and psychological traits, using the final dataset of a large-scale prospective cohort study in Japan. We identified 209 cases of incident breast cancer out of a maximum 21-year follow-up of 29,098 Japanese women. Cox proportional hazard regression analysis, adjusted for the same potential confounders used in our previous study, did not reveal any significant relationships between breast cancer incidence and four psychological traits: having "ikigai", decisiveness, ease of anger arousal, and perceived stress. Our finding is consistent with previous studies, and suggests that the psychological traits are unlikely to be an important risk factor for breast cancer.

Psychological stress, adverse life events and breast cancer incidence: a cohort investigation in 106,000 women in the United Kingdom

Background

Women diagnosed with breast cancer frequently attribute their cancer to psychological stress, but scientific evidence is inconclusive. We investigated whether experienced frequency of stress and adverse life events affect subsequent breast cancer risk.

Methods

Breast cancer incidence was analysed with respect to stress variables collected at enrolment in a prospective cohort study of 106,000 women in the United Kingdom, with 1783 incident breast cancer cases. Relative risks (RR) were obtained as hazard ratios using Cox proportional hazards models.

Results

There was no association of breast cancer risk overall with experienced frequency of stress. Risk was reduced for death of a close relative during the 5 years preceding study entry (RR = 0.87, 95 % confidence interval (CI): 0.78–0.97), but not for death of a spouse/partner or close friend, personal illness/injury, or divorce/separation. There was a positive association of divorce with oestrogen-receptor-negative (RR = 1.54, 95 % CI: 1.01–2.34), but not with oestrogen-receptor-positive breast cancer. Risk was raised in women who were under age 20 at the death of their mother (RR = 1.31, 95 % CI: 1.02–1.67), but not of their father, and the effect was attenuated after excluding mothers with breast or ovarian cancer (RR = 1.17, 95 % CI: 0.85–1.61).

Conclusions

This large prospective study did not show consistent evidence for an association of breast cancer risk with perceived stress levels or adverse life events in the preceding 5 years, or loss of parents during childhood and adolescence.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-016-0733-1) contains supplementary material, which is available to authorized users.

The impact of cancer and quality of life among long-term survivors of breast cancer in Austria

PURPOSE

This study explores the relationship between the perceived impact of cancer among long-term breast cancer survivors, sociodemographic and clinical variables, and mental and physical health-related quality of life outcomes in Austria.

METHODS

One hundred and fifty-two long-term survivors of breast cancer (on average 13 years after initial diagnosis) completed three mailed surveys, including the Short Form-36 (SF-36), the Impact of Cancer (version 2) to assess the perceived positive and negative aspects of cancer survivorship, and a general sociodemographic and clinical questionnaire. Linear regression models were constructed to determine the effects of the perceived positive and negative impact of cancer on mental and physical health-related quality of life.

RESULTS

Respondents reported a physical health status that centered on population norms for Austria, but scored lower on mental health status. After controlling for age, chemotherapy, exercise, and BMI, the positive impact of cancer was associated with improved physical functioning (p = 0.0014) and the negative impact of cancer was associated with poorer physical functioning (p < 0.0001). After controlling for age, marital status, the belief in emotional distress as a cause of cancer, and high stress levels, the negative impact of cancer was associated with poorer mental functioning (p < 0.0001). Higher perceived positive impact of cancer was not associated with improved mental functioning.

CONCLUSIONS

Long-term survivors of breast cancer in Austria perceive both positive and negative impacts of breast cancer. These perceptions, in particular the negative impact of cancer, appear to influence, or are potentially influenced by, physical and mental health-related quality of life.

Stress Exposure in Significant Relationships Is Associated with Lymph Node Status in Breast Cancer

Objective

Life stress exposure may impact on health and disease. Previous literature showed that stressful life events are associated with cancer incidence, survival and mortality. In animal models, patterns of maternal care have been shown to critically affect stress sensitivity and immunity trajectories later in life, by modifying DNA methylation during critical periods early in life. However, the role of parental care in breast cancer progression and survival has only limitedly been explored. Here, we investigated whether these factors may be linked to biological prognostic variables.

Methods

One hundred twenty-three women hospitalized for surgery of primary breast cancer completed a questionnaire assessing parental bonding. Stressful events throughout the life span were also assessed.

Results

We found that the absence of optimal parental relationships is significantly associated with an increased risk of lymph node involvement, adjusting for confounders, while cumulative stress in the area of sentimental relationships is borderline significantly associated with the same prognostic factor.

Conclusions

Our results suggest that parental bonding and sentimental relations may have a role in breast cancer progression. These variables represent an important evolutionary aspect which may modulate cancer progression through psycho-physiological stress pathways and influence the immune system.

Stressors, stress response, and cancer recurrence: a systematic review

BACKGROUND

Cancer survivors assume that stress plays an important role in cancer recurrence. However, the role of stress in the etiology of cancer recurrence remains unclear.

OBJECTIVE

A systematic review examining the causal role of exposure to stressors and/or stress response and cancer recurrence was conducted.

METHODS

The authors screened the scientific literature published from December 1979 through April 2012. Prospective studies and randomized control trials that examined the link between exposure to stressors and/or stress response and cancer recurrence were included in the review.

RESULTS

Fifteen studies examined exposures to stressors (life event questionnaires) and/or multiple indices of the stress response (mood, anxiety, depression, biological, and immune measures). The relationships between stressors and/or stress response and recurrence were observed as no relationship (80%), positive relationship (33%), and inverse relationship (27%). One of 3 randomized control trials reported a positive relationship between stress reduction and reduced risk of recurrence.

CONCLUSIONS

The scientific literature to date indicates no clear evidence for a causal relationship between stress (measured as stressor exposure and/or stress response) and cancer recurrence. Although additional high-quality research is needed to provide a more definitive answer, the evidence to date does not support this hypothesis.

IMPLICATIONS FOR PRACTICE

Although at present, there is no evidence indicating a causal relationship between stress and cancer recurrence, attending to the reduction in a cancer survivor's stress response can improve emotional well-being and quality of life.

Social defeat stress promotes tumor growth and angiogenesis by upregulating vascular endothelial growth factor/extracellular signal-regulated kinase/matrix metalloproteinase signaling in a mouse model of lung carcinoma

Numerous epidemiological and experimental animal studies have indicated that chronic psychological stress may promote tumor development. However, the underlying molecular mechanisms by which chronic stress promotes tumorigenesis remain to be fully elucidated and animal models have not yet been well established. In the present study, an established mouse model of repeated social defeat stress (RSDS), was generated and used to investigate the effect of stress on tumor growth and metastasis. C57BL/6 mice were exposed to RSDS for 10 days, followed by subcutaneousl inoculation with Lewis lung carcinoma cells for seven days. The tumor weight and volume as well as the number of the lung metastatic nodules were then determined. Vascular endothelial growth factor (VEGF) serum levels were measured using ELISAs. In addition, expression levels of VEGF receptor (VEGFR) and L1 cell adhesion molecule (L1CAM) messenger (m)RNA were confirmed using reverse transcription quantitative polymerase chain reaction. Furthermore, protein expression levels of phosphorlyated extracellular signal-regulated kinase (pERK), matrix metalloproteinase (MMP)-2 and MMP-9 were examined using western blot analysis. The results showed that RSDS significantly increased the weight and the volume of the primary tumor as well as the number of the lung metastatic nodules. Serum VEGF levels were significantly higher in the tumor-stress group compared with those of the unstressed tumor mice. In addition, tumors in stressed animals demonstrated markedly enhanced expression of VEGFR-2 and L1CAM mRNA as well as pERK, MMP-2 and MMP-9 protein expression. In conclusion, these results suggested that RSDS contributed to lung cancer progression, angiogenesis and metastasis, which was partially associated with increased VEGF secretion and therefore the activation of the ERK signaling pathway, resulting in the induction of MMP-2 and MMP-9 protein expression.

Cancer incidence and mortality following exposures to distal and proximal major stressors

PURPOSE

Severe psychological trauma has been shown to leave psychological and biological sequelae, including compromise of the neuro-hormonal and immunological systems. Despite much research, the putative effect of such stressor on cancer remains ambiguous. This study maximized the exploration of cancer incidence and mortality by combining a proximal (parental bereavement) with a distal major stressor (Holocaust exposure) on both risks.

METHODS

Subjects were bereaved Holocaust survivors (n = 904) and comparison individuals (n = 933) selected from the total cohort of 6,284 Jewish-Israeli parents who lost an adult son in war or from non-self-inflicted external causes. Cox regression was used to examine the differential risk for cancer between the two bereaved samples, adjusting for potential confounders.

RESULTS

No difference in cancer incidence or mortality was observed between both groups of bereaved parents. However, prior to bereavement, Holocaust survivors had an increased cancer risk compared with their counterparts in the general population.

CONCLUSIONS

Individuals who faced both a proximal (bereavement) and distal (Holocaust) major stressors had no additive risk for cancer incidence and mortality.

Psychological reactivity to laboratory stress is associated with hormonal responses in postmenopausal women

OBJECTIVE

The present study examined associations between psychological reactivity and hormonal responses to a standardized laboratory stressor (Trier Social Stress Test, TSST) in postmenopausal women.

METHODS

Postmenopausal women aged 50-74 years undertook anxiety and mood assessments prior to and following the TSST. Blood samples were drawn at multiple timepoints for assessment of cortisol, adrenocorticotrophic hormone (ACTH) and dehydroepiandrosterone (DHEA).

RESULTS

Forty postmenopausal women completed the assessments. As expected, significant increases in anxiety and negative affect and decreases in positive affect were observed after the TSST; however, the magnitude of change in anxiety and mood varied considerably across individuals. Analyses indicated that greater increases in anxiety and negative affect after the TSST were associated with higher levels of cortisol, ACTH and DHEA after controlling for race, age, body mass index and smoking status. Changes in positive affect were not associated with cortisol, ACTH or DHEA.

CONCLUSIONS

These findings suggest that enhanced reactivity to stress is associated with higher hormone levels among postmenopausal women, which could have potential implications for health.

Childhood adversity as a risk for cancer: findings from the 1958 British birth cohort study

BACKGROUND

To analyse whether Adverse Childhood Experiences (ACE) are associated with an increased risk of cancer.

METHODS

The National child development study (NCDS) is a prospective birth cohort study with data collected over 50 years. The NCDS included all live births during one week in 1958 (n=18558) in Great Britain. Self-reported cancer incidence was based on 444 participants reporting having had cancer at some point and 5694 reporting never having cancer. ACE was measured using reports of: 1) child in care, 2) physical neglect, 3) child's or family's contact with the prison service, 4) parental separation due to divorce, death or other, 5) family experience of mental illness & 6) family experience of substance abuse. The resulting variable had three categories, no ACEs/ one ACE/ 2+ACEs and was used to test for a relationship with cancer. Information on socioeconomic characteristics, pregnancy and birth were extracted as potential confounders. Information on adult health behaviours, socioeconomic environment, psychological state and age at first pregnancy were added to the models. Multivariate models were run using multiply-imputed data to account for missing data in the cohort.

RESULTS

The odds of having a cancer before 50 y among women increased twofold for those who had 2+ ACEs versus those with no ACEs, after adjusting for adult factors and early life confounders (OR: 2.1, 95% CI: 1.42-3.21, p<0.001).

CONCLUSION

These findings suggest that cancer risk may be influenced by exposure to stressful conditions and events early on in life. This is potentially important in furthering our understanding of cancer aetiology, and consequently in redirecting scientific research and developing appropriate prevention policies.

Striking life events associated with primary breast cancer susceptibility in women: a meta-analysis study

Purpose

The association between striking life events, an important stress and acute anxiety disorder, and the occurrence of primary breast cancer is unclear. The current meta-analysis was designed to assess the relationship between striking life events and primary breast cancer incidence in women.

Methods

Systematic computerized searching of the PubMed, ScienceDirect, Embase, and BMJ databases with the combinations of controlled descriptors from Mesh, including breast cancer, breast tumor, cancer of breast, mammary carcinoma, life events, life change events, case–control studies, case-base studies, cohort study, and cohort analysis and identified a total of 307 papers published from January 1995 to April 2012. Following evaluation of methodological quality with the Downs & Black criteria, seven case–control or cohort studies were selected and the association between striking life events and primary breast cancer incidence in women was measured using random effect or fixed-effect odds ratios combined with 95% confidence interval.

Results

The seven studies included in the final meta-analysis included 99,807 women. A meta-analysis showed that the pooled OR for striking life events and breast cancer was 1.51 (95% CI 1.15 - 1.97, P = 0.003), indicating that women with striking life events were at 1.5-fold greater risk of developing breast cancer. The pooled OR for severe striking life events and breast cancer was 2.07 (95% CI 1.06 - 4.03), indicating that women with severe striking life events were at 2-fold greater risk of developing breast cancer.

Conclusions

The current meta-analysis showed significant evidence for a positive association between striking life events and primary breast cancer incidence in women.

Increased risk of coronary heart disease among individuals reporting adverse impact of stress on their health: the Whitehall II prospective cohort study

AIM

Response to stress can vary greatly between individuals. However, it remains unknown whether perceived impact of stress on health is associated with adverse health outcomes. We examined whether individuals who report that stress adversely affects their health are at increased risk of coronary heart disease (CHD) compared with those who report that stress has no adverse health impact.

METHODS AND RESULTS

Analyses are based on 7268 men and women (mean age: 49.5 years, interquartile range: 11 years) from the British Whitehall II cohort study. Over 18 years of follow-up, there were 352 coronary deaths or first non-fatal myocardial infarction (MI) events. After adjustment for sociodemographic characteristics, participants who reported at baseline that stress has affected their health 'a lot or extremely' had a 2.12 times higher (95% CI 1.52-2.98) risk of coronary death or incident non-fatal MI when compared with those who reported no effect of stress on their health. This association was attenuated but remained statistically significant after adjustment for biological, behavioural, and other psychological risk factors including perceived stress levels, and measures of social support; fully adjusted hazard ratio: 1.49 (95% CI 1.01-2.22).

CONCLUSIONS

In this prospective cohort study, the perception that stress affects health, different from perceived stress levels, was associated with an increased risk of coronary heart disease. Randomized controlled trials are needed to determine whether disease risk can be reduced by increasing clinical attention to those who complain that stress greatly affects their health.