Global untargeted and individual targeted plasma metabolomics of breast cancer recurrence modified by hormone receptors.

BACKGROUND: Breast cancer is a heterogeneous and complex etiological disease. Understanding perturbations of circulating metabolites could improve prognosis. METHODS: We recruited breast cancer patients from Kaohsiung Medical University (KMU) to perform untargeted (case-control design) and targeted (patient cohort) metabolomics analyses in the discovery and validation phases to evaluate interaction effects between clinical factors and plasma metabolites using multivariable Cox proportional hazards model. RESULTS: In the discovery phase, partial least squares-discriminant analysis (PLS-DA) showed that plasma metabolites were significantly different between recurrent and non-recurrent breast cancer patients. Metabolite set enrichment analysis (MSEA) and metabolomic pathway analysis (MetPA) showed that valine, leucine, and isoleucine degradation was the significant pathway, and volcano plot showed significant ten upregulated and two downregulated metabolites between recurrent and non-recurrent cases. Combined with receiver operating characteristic (ROC) curve and biological significance, creatine, valine, methionine, and mannose were selected for the validation phase. In this patient cohort with 41 new-recurrent vs. 248 non-recurrent breast cancer cases, followed for 720.49 person-years, compared with low level of valine, high valine level was significantly negatively associated with recurrent breast cancer (aHR: 0.36, 95% CI: 0.18-0.72, P = 0.004), especially in ER-negative and PR-negative status. There were interaction effects between valine and ER (Pinteraction = 0.006) as well as PR (Pinteraction = 0.002) on recurrent breast cancer. After Bonferroni correction, stratification effects between valine and hormone receptors were still significant. CONCLUSION: Our study revealed that plasma metabolites were significantly different between recurrent and non-recurrent patients, proposing therapeutic insights for breast cancer prognosis.

Circulating Short-Chain Fatty Acids and Non-Alcoholic Fatty Liver Disease Severity in Patients with Type 2 Diabetes Mellitus.

(1) Background: Non-alcoholic fatty liver disease (NAFLD) is a major global health concern. The increasing prevalence of NAFLD has been related to type 2 diabetes mellitus (T2D). However, the relationship between short-chain fatty acids (SCFAs) and NAFLD severity is ambiguous in T2D subjects. This study aimed to explore the association of SCFAs with the severity of NAFLD in T2D patients. (2) Methods: We employed echography to examine the severity of hepatic steatosis. The serum levels of nine SCFAs, namely, formate, acetate, propionate, butyrate, isobutyrate, methylbutyrate, valerate, isovalerate, and methylvalerate, were measured using gas chromatography mass spectrometry. (3) Results: A total of 259 T2D patients was enrolled in this cross-sectional study. Of these participants, 117 with moderate to severe NAFLD had lower levels of formate, isobutyrate, and methylbutyrate than the 142 without NAFLD or with mild NAFLD. Lower circulating levels of isobutyrate and methylbutyrate were associated with an increased severity of NAFLD. A relationship between NAFLD severity and circulating isobutyrate and methylbutyrate levels was found independently of a glycated hemoglobin (HbA1C) level of 7.0%. (4) Conclusion: Circulating levels of isobutyrate and methylbutyrate were significantly and negatively correlated with NAFLD severity in the enrolled T2D patients. SCFAs may be related to NAFLD severity in T2D patients.

Oral short-chain fatty acids administration regulates innate anxiety in adult microbiome-depleted mice.

Anxiety is characterized by feelings of tension and worry even in the absence of threatening stimulus. Pathological condition of anxiety elicits defensive behavior and aversive reaction ultimately impacting individuals and society. The gut microbiota has been shown to contribute to the modulation of anxiety-like behavior in rodents through the gut-brain axis. Several studies observed that germ-free (GF) and the broad spectrum of antibiotic cocktail (ABX)-treated rodents display lowered anxiety-like behavior. We speculate that gut microbial short-chain fatty acids (SCFA) modulate the innate anxiety response. Herein, we administered SCFA in the drinking water in adult mice treated with ABX to deplete the microbiota and tested their anxiety-like behavior. To further augment the innate fear response, we enhanced the aversive stimulus of the anxiety-like behavior tests. Strikingly, we found that the anxiety-like behavior in ABX mice was not altered when enhanced aversive stimulus, while control and ABX mice supplemented with SCFA displayed increased anxiety-like behavior. Vagus nerve serves as a promising signaling pathway in the gut-brain axis. We determined the role of vagus nerve by subdiaphragmatic vagotomy (SDV) in ABX mice supplemented with SCFA. We found that the restored anxiety-like behavior in ABX mice by SCFA was unaffected by SDV. These findings suggest that gut microbiota can regulate anxiety-like behavior through their fermentation products SCFA.

Association between recurrent breast cancer and phthalate exposure modified by hormone receptors and body mass index.

The association between phthalate exposure and breast cancer remains controversial. We performed a prospective patient cohort design to explore the interaction between creatinine-corrected urinary phthalate metabolites and hormone receptors as well as body mass index (BMI) on recurrent breast cancer. In this follow-up study, 636 female breast cancer patients and 45 new recurrent cases diagnosed for a total of 1576.68 person-years of follow-up were recruited. Mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) was negatively associated with breast cancer recurrence, with adjusted hazard ratio (aHR) 3rd vs. 1st quartile of 0.15 (95% CI 0.04-0.51). The MEOHP presented as a non-monotonic dose-response (NMDR) curve, being U-shaped. In the stratification of hormone receptors, MEOHP still exhibited a U-shaped dose-response curve. The third quartile of MEOHP showed significant lowest recurrent risk in the status of ER-positive (aHR 0.18, 95% CI 0.05-0.66), PR-negative (aHR 0.14, 95% CI 0.03-0.63), and HER2-negative (aHR 0.24, 95% CI 0.08-0.76). Whether in BMI < 25 or in BMI ≥ 25, the third quartile of MEOHP was negatively associated with recurrent breast cancer, and there was a negative interaction on an additive scale between MEOHP and BMI (pinteraction = 0.042). The association between MEOHP and recurrent breast cancer was modified by hormone receptors and BMI.

A novel role for ß2-microglobulin: a precursor of antibacterial chemokine in respiratory epithelial cells.

We analyzed a panel of cationic molecules secreted in the culture medium of human respiratory epithelial cells (REC) upon activation by IL-1ß and different pathogen-associated molecular patterns. A 9 kDa fragment derived from ß2-microglobulin (B2M) was identified and named shed 9 kDa B2M (sB2M-9). The primary structure of sB2M-9 was revealed to increase its pI value that potentially could play an important role in innate defense. sB2M-9 exhibits antibacterial activity against Gram positive Staphylococcus aureus (SA) but not against Gram negative Klebsiella pneumonia (KP). Upon its binding to SA, sB2M-9 induces clumps, a phenomenon not observed with B2M. Migration of THP-1 monocytes exposed to SA clumps was significantly greater than that to SA without clumps. sB2M-9 binds to SA, more likely as a chemokine, to facilitate THP-1 migration. As a whole, we demonstrated that REC release a novel chemokine with antibacterial activity that is shed from B2M to facilitate THP-1 migration.