Association between weight change and breast cancer prognosis.

PURPOSE: Results of the associations between weight change after breast cancer diagnosis and prognosis were inconsistent. The modification effects of menopausal status and endocrine therapy on the associations remain poorly understood. METHODS: A total of 2016 breast cancer patients were recruited between October 2008 and January 2018 and followed up until December 31, 2019 in Guangzhou. Multivariate Cox models were used to estimate the hazard ratios (HRs) and 95% confidence intervals (95% CIs) for progression-free survival (PFS) in association with weight change after diagnosis. RESULTS: Weight loss at 2 years (HR = 1.34, 95% CI 0.87-2.06) or more than 2 years (HR = 1.95, 95% CI 1.22-3.10) after diagnosis increased risk of breast cancer progression. The adverse effect of weight loss was significantly more pronounced in post-menopausal than pre-menopausal women, particularly for weight loss at 2 years after diagnosis, with the HRs and 95% CIs of 2.41 (1.25-4.63) and 0.90 (0.49-1.64), respectively. Weight gain tended to reduce the risk of disease progression among patients with endocrine therapy but not for those with non-endocrine therapy; the significant interaction between weight gain at 2 years after diagnosis and endocrine therapy was observed (Pinteraction = 0.042). CONCLUSION: Our finding suggested that weight loss was detrimental to breast cancer prognosis, particularly for post-menopausal women, while weight gain may be a potential beneficial indicator for the patients with endocrine therapy but not for those with non-endocrine therapy.

Time-varying effects of FOXA1 on breast cancer prognosis.

PURPOSE: Results of previous studies on the associations between Forkhead box A1 (FOXA1) expression in breast cancer tissues and the prognosis varied depending on the follow-up durations. The present study would investigate whether there is a time-varying effect of FOXA1 in breast cancer tissues on the prognosis. METHODS: FOXA1 expressions were evaluated in 1041 primary invasive breast tumors with tissue microarrays by immunohistochemistry. Cox models with restricted cubic splines and Kaplan-Meier survival analysis were used to examine the associations between FOXA1 and the prognosis. Flexible parametric models were applied to explore the time-varying effect of FOXA1. RESULTS: Overall, the association between FOXA1 expression and the prognosis was not significant but varied on the time of follow-up. Compared to FOXA1 ≤ 270 of H-score, the hazard ratios (HRs) of death for those with 271-285 of FOXA1 expression increased from 0.35 (95% CI 0.14-0.86) at 6 months after diagnosis to 2.88 (95% CI 1.35-6.15) at 120 months with a crossover at around 36 months. Similar patterns were also observed for FOXA1 > 285 of H-score and for progression free survival (PFS). Moreover, when allowed both FOXA1 and estrogen receptor (ER) to change over time in the model (considering that ER had a similar time-varying effect), these time-varying effects remained for FOXA1 on both overall survival (OS) (P < 0.01) and PFS (P = 0.01) but were attenuated for ER (P = 0.13 for OS). CONCLUSIONS: This study revealed an independent time-varying effect of FOXA1 on breast cancer prognosis, which would provide an insight into the roles of FOXA1 as a marker of breast cancer prognosis and may help optimize the medication strategies.

Effects of Infection-Induced Fever and the Interaction with IL6 rs1800796 Polymorphism on the Prognosis of Breast Cancer.

BACKGROUND: Previous studies have found that acute febrile infection may decrease the risk of breast cancer. Meanwhile, it is well known that interleukin-6 (IL6) played dual roles in the tumor microenvironment. Fever may stimulate IL6 production, and IL6 rs1800796 also influences the expression of IL6. However, the impact of fever and its interaction with IL6 rs1800796 on breast cancer survival remains to be explored. METHODS: This was a prospective cohort study of 4,223 breast cancer patients. Exposures were pre-/postdiagnostic infection-induced fever and rs1800796 polymorphism. The endpoints were overall survival (OS) and progression-free survival (PFS). Adjusted hazard ratios were obtained using multivariate Cox proportional hazards regression models. RESULTS: Compared with women without prediagnostic fever, the adjusted hazard ratio (HR) of progression for those with prediagnostic fever was 0.81 (95% CI, 0.66-0.99), particularly for the CC genotype of IL6 rs1800796 (HR, 0.53; 95% CI, 0.36-0.79). OS was also better (HR, 0.59; 95% CI, 0.36-0.99) among women with the CC genotype exposed to prediagnostic fever, accompanied by a significant interaction (P = 0.021). Postdiagnostic fever conferred better PFS for breast cancer (HR, 0.72; 95% CI, 0.52-1.00). Irrespective of the genotype of IL6, lymph node-positive women with postdiagnostic fever (HR, 0.57; 95% CI, 0.37-0.89) had a lower risk of progression than lymph node-negative women (HR, 1.12; 95% CI, 0.70-1.79). CONCLUSIONS: Infection-induced fever was beneficial to breast cancer survival, particularly for women who were the CC genotype of IL6 rs1800796 or node positive. IMPACT: This study provides new insight into the roles of infection-induced fever as a potential prognostic marker and therapy regimen for breast cancer.

Prognostic value of glutaminase 1 in breast cancer depends on H3K27me3 expression and menopausal status.

Glutaminase 1 (GLS) is a therapeutic target for breast cancer; although GLS inhibitors have been developed, only a few subjects responded well to the therapy. Considering that the expression of histone H3 lysine 27 trimethylation (H3K27me3) and menopausal status was closely linked to GLS, we examined the effects of H3K27me3 and menopausal status on GLS to breast cancer prognosis. Data for 962 women diagnosed with primary invasive breast cancer were analyzed. H3K27me3 and GLS expression in tumors were evaluated with tissue microarrays by immunohistochemistry. Hazard ratios (HRs) and their 95% confidence intervals (CIs) for overall survival and progression-free survival were estimated using Cox regression models. Statistical interaction was assessed on multiplicative scale. There was a beneficial prognostic effect of GLS expression on overall survival for those with low H3K27me3 level (HR = 0.50, 95% CI: 0.20-1.28) but an adverse prognostic effect for those with high H3K27me3 level (HR = 3.90, 95% CI: 1.29-11.78) among premenopausal women, and the statistical interaction was significant (Pinteraction = 0.003). Similar pattern was further observed for progression-free survival (HR = 0.44, 95% CI: 0.20-0.95 for low H3K27me3 level, HR = 1.35, 95% CI: 0.74-2.48 for high H3K27me3 level, Pinteraction = 0.024). The statistical interaction did not occur among postmenopausal women. Our study showed that the prognostic effects of GLS on breast cancer correlated to the expression level of H3K27me3 and menopausal status, which would help optimize the medication strategies of GLS inhibitors.

Identification of epigenetic modifications mediating the antagonistic effect of selenium against cadmium-induced breast carcinogenesis.

The antagonistic effect of selenium (Se) against cadmium (Cd)-induced breast carcinogenesis was reported, but underlying mechanisms were unclear. The aim of this study was to identify the epigenetically regulated genes and biological pathways mediating the antagonistic effect. We exposed MCF-7 cells to Cd and Se alone or simultaneously. Cell proliferation was assessed by MTT assay, and differential epigenome (DNA methylation, microRNA, and long non-coding RNA) was obtained by microarrays. We cross-verified the epigenetic markers with differential transcriptome, and the ones modulated by Cd and Se in opposite directions were regarded to mediate the antagonistic effect. The epigenetically regulated genes were validated by using gene expression data in human breast tissues. We further assessed the biological functions of these validated genes. Our results showed that Se alleviated the proliferative effect of Cd on MCF-7 cell. A total of 10 epigenetically regulated genes were regarded to mediate the antagonistic effect, including APBA2, KIAA0895, DHX35, CPEB3, SVIL, MYLK, ZFYVE28, ABLIM2, GRB10, and PCDH9. Biological function analyses suggested that these epigenetically regulated genes were involved in multiple cancer-related pathways, such as focal adhesion and PI3K/Akt pathway. In conclusion, we provided evidence that Se antagonized the Cd-induced breast carcinogenesis via epigenetic modification and revealed the critical pathways.

Differential epigenetic profiles induced by sodium selenite in breast cancer cells.

OBJECTIVES: Selenium (Se) was a potential anticancer micronutrient with proposed epigenetic effect. However, the Se-induced epigenome in breast cancer cells was yet to be studied. METHODS: The profiles of DNA methylation, microRNA (miRNA), long non-coding RNA (lncRNA), and message RNA (mRNA) in breast cancer cells treated with sodium selenite were examined by microarrays. We verified the epigenetic modifications by integrating their predicted target genes and differentially expressed mRNAs. The epigenetically regulated genes were further validated in a breast cancer cohort by associating with tumor progression. We conducted a series of bioinformatics analyses to assess the biological function of these validated genes and identified the critical genes. RESULTS: The Se-induced epigenome regulated the expression of 959 genes, and 349 of them were further validated in the breast cancer cohort. Biological function analyses suggested that these validated genes were enriched in several cancer-related pathways, such as PI3K/Akt and metabolic pathways. Based on the degrees of expression change, hazard ratio difference, and connectivity, NEDD4L and FMO5 were identified as the critical genes. CONCLUSIONS: These results confirmed the epigenetic effects of sodium selenite and revealed the epigenetic profiles in breast cancer cells, which would help understand the mechanisms of Se against breast cancer.

Differential epigenetic and transcriptional profile in MCF-7 breast cancer cells exposed to cadmium.

Cadmium (Cd) has been confirmed to be associated with breast carcinogenesis, but the mechanism was not clarified yet. Given that epigenetic modification was speculated as underlying mechanism, we examined the differential epigenome caused by Cd in breast cancer cells. Profiles of DNA methylation, microRNA (miRNA), long non-coding RNA (lncRNA), and message RNA (mRNA) were derived from Cd-treated and untreated MCF-7 breast cancer cells by microarray. We identified 997 target genes epigenetically regulated by Cd through cross-verification with the differential epigenome and transcriptome, and 400 of them were further validated in a breast cancer cohort. Biological function analyses suggested that several pathways were involved in Cd-induced breast carcinogenesis, such as Wnt signaling, metabolism, and human papilloma virus (HPV) infection. TXNRD1 and CCT3 were further identified as the critical genes based on the degree of expression change, hazard ratio difference, and connectivity. The present study revealed that Cd epigenetically regulated several pathways involving in breast carcinogenesis, particularly the Wnt signaling and metabolic pathways, among which TXNRD1 and CCT3 might play critical roles. It was also suggested that Cd and HPV infection might jointly participate in breast tumorigenesis.

Associations of reproductive factors with breast cancer prognosis and the modifying effects of menopausal status.

Reproductive factors associated with breast cancer risk may also affect the prognosis. This study aimed to evaluate the associations of multiple reproductive factors with breast cancer prognosis and the modifying effects of menopausal status. We obtained data from 3805 breast cancer patients recruited between October 2008 and June 2016 in Guangzhou. The subjects were followed up until 30 June 2018. The hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated using multivariate Cox models to estimate the associations. It was found that there were U-shaped patterns for the associations of age at first birth and durations from first/last birth to diagnosis with breast cancer prognosis. The adverse effects of old age at first birth [>30 years vs 23-30 years, HR (95% CI): 1.59 (1.01-2.50)] and long intervals from first [≥20 years vs 10-19 years, HR (95% CI): 1.55 (1.07-2.27)] or last [≥20 years vs 10-19 years, HR (95% CI): 1.63 (1.08-2.46)] birth to diagnosis on progression-free survival (PFS) were significantly more pronounced among premenopausal women. Additionally, long interval (>5 years) between first and second birth was associated with a better PFS [HR (95% CI): 0.64 (0.42-0.97)]. These results suggested that age at first birth, durations from first/last birth to diagnosis, and intervals between first and second birth should be taken into account when following the patients and assessing the prognosis of breast cancer, particularly for premenopausal patients. These findings would also have implications for further insight into the mechanisms of breast cancer development.

Joint effects of multiple sleep characteristics on breast cancer progression by menopausal status.

OBJECTIVES: Sleep has been closely linked to breast cancer risk. However, the association between sleep and breast cancer prognosis remains unclear. The aim of this study was to evaluate the separate and joint effects of multiple sleep characteristics on breast cancer prognosis among Chinese women. METHODS: A total of 1580 breast cancer patients were recruited between October 2008 and December 2014 and followed up until December 31, 2017 in Guangzhou. Multivariate Cox models were conducted to estimate the hazard ratios (HR) and 95% confidence intervals (95%CI) for breast cancer prognosis in association with sleep characteristics. RESULTS: Long sleep duration at night (>9 h) (HR = 2.33, 95%CI: 1.01-5.42), poor sleep quality (HR = 3.08, 95%CI: 1.74-5.47), and impaired daytime function (HR = 2.49, 95%CI: 1.65-3.79) after diagnosis were associated with an increased risk of breast cancer progression. Both short sleep duration (<6 h) (HR = 2.00, 95%CI: 1.06-3.77, Pinteraction = 0.011) and long sleep duration (>9 h) (HR = 4.69, 95%CI: 1.31-16.78, Pinteraction = 0.187) increased the progression risk only among patients with impaired but not normal daytime function. In addition, daytime napping significantly modified the effect of short sleep duration on the progression (HR = 3.55, 0.59, 95%CI: 1.55-7.97, 0.23-1.53 for patients without and with daytime napping, respectively, Pinteraction = 0.005). Stratification results suggested that the associations were more evident among pre-menopausal patients, although no significant interaction was observed. CONCLUSION: Our findings suggested that inadequate sleep duration to feel one's best and poor sleep quality after diagnosis were associated with an increased risk of breast cancer progression, particularly for pre-menopausal women.