Association between diverticular disease and colorectal cancer: a bidirectional mendelian randomization study.

BACKGROUND: Diverticular disease has been inconsistently associated with colorectal cancer risk. We conducted a bidirectional Mendelian randomization study to assess this association. METHODS: Forty-three and seventy single-nucleotide polymorphisms associated with diverticular disease and colorectal cancer at the genome-wide significance level (p < 5 × 10- 8) were selected as instrumental variables from large-scale genome-wide association studies of European descent, respectively. Summary-level data for colon cancer, rectum cancer, and colorectal cancer were obtained from genome-wide association analyses of the FinnGen consortium and the UK Biobank study. Summary-level data for diverticular disease was derived from a genome-wide association study conducted in the UK Biobank population. The random effect inverse-variance weighted Mendelian randomization approach was used as the primary method and MR-Egger, weighted-median, and MR-PRESSO approaches were conducted as sensitivity analyses. RESULTS: Genetically determined diverticular disease was associated with a higher risk of colorectal cancer (beta = 0.441, 95%CI: 0.081-0.801, P = 0.016) in the FinnGen population, but the association was not found in the UK Biobank (beta = 0.208, 95%CI: -0.291,0.532, P = 0.207). The positive association remained consistent direction in the three sensitivity analyses. In the stratified analysis in the FinnGen consortium, an association was found to exist between genetically predicted diverticular disease and colon cancer (beta = 0.489, 95%CI: 0.020-0.959, P = 0.041), rather than rectum cancer (beta = 0.328, 95%CI: -0.119-0.775, P = 0.151). Besides, we found a slight association between colorectal cancer and diverticular disease (beta = 0.007, 95%CI: 0.004-0.010, P < 0.001) when using colorectal cancer as exposome and diverticular disease as outcome. However, there is a large sample overlap in this step of analysis. CONCLUSION: This Mendelian randomization study suggests that diverticular disease may be a possible risk factor for colorectal cancer and colon cancer rather than rectum cancer in the FinnGen population.

The mechanisms governing mouse embryonic palate mesenchymal cells' proliferation associated with atRA-induced cleft palate in mice: insights from integrated transcriptomic and metabolomic analyses.

While exposure to high levels of all-trans retinoic acid (atRA) during pregnancy is known to suppress murine embryonic palate mesenchymal (MEPM) cells proliferation and to result in cleft palate (CP) development, the underlying mechanisms are poorly understood. Accordingly, this study was designed with the goal of clarifying the etiological basis for atRA-induced CP. A murine model of CP was established via the oral administration of atRA to pregnant mice on gestational day (GD) 10.5, after which transcriptomic and metabolomic analyses were performed with the goal of clarifying the critical genes and metabolites associated with CP development through an integrated multi-omics approach. MEPM cells proliferation was altered by atRA exposure as expected, contributing to CP incidence. In total, 110 genes were differentially expressed in the atRA treatment groups, suggesting that atRA may influence key biological processes including stimulus, adhesion, and signaling-related activities. In addition, 133 differentially abundant metabolites were identified including molecules associated with ABC transporters, protein digestion and absorption, mTOR signaling pathway, and the TCA cycle, suggesting a link between these mechanisms and CP. Overall, combined analyses of these transcriptomic and metabolomic results suggested that the MAPK, calcium, PI3K-Akt, Wnt, and mTOR signaling pathways are particularly important pathways enriched in the palatal cleft under conditions of atRA exposure. Together, these integrated transcriptomic and metabolomic approaches provided new evidence with respect to the mechanisms underlying altered MEPM cells proliferation and signal transduction associated with atRA-induced CP, revealing a possible link between oxidative stress and these pathological changes.

The role of MEG3 in the proliferation of palatal mesenchymal cells is related to the TGFß/Smad pathway in TCDD inducing cleft palate.

Cleft palate (CP) is a common birth defect with a high incidence of occurrence in humans. The 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin (TCDD) is a highly toxic halogenated aromatic hydrocarbon, with a strong CP effect on mice. Increasing recent evidences have shown that long-noncoding RNAs (lncRNAs) play an important role in several diseases, including CP. However, there is a paucity of studies on the role of lncRNA MEG3 in the occurrence and development of TCDD-induced CP. In this study, the relationship between MEG3 and the proliferation of palatal mesenchymal cells and the underlying molecular mechanism were studied by establishing fetal CP with TCDD (64 µg/kg) in C57BL/6N mice. The results revealed that MEG3 was highly expressed during the critical period of CP formation and that the fetal mesenchymal proliferation was significantly inhibited at certain critical periods in the mice receiving TCDD. In addition, we noted a possibility of a crosstalk between MEG3 and the TGF-ß/Smad pathway, such that the inhibition of the TGF-ß/Smad pathway was induced by TCDD. Cumulatively, our study suggests that TCDD-induced CP may be caused by MEG3 inhibition of the proliferation of palatal mesenchymal cells involving the TGFß/Smad pathway, which may provide a novel perspective to understand the pathogenesis of CP.

Glycogen synthase kinase-3ß promotes radiation-induced lung fibrosis by regulating ß-catenin/lin28 signaling network to determine type II alveolar stem cell transdifferentiation state.

The role of type II alveolar epithelial stem cells (AEC II) for alveolar repair in radiation-induced lung fibrosis (RILF) remains largely unknown, mainly because of AEC II phenotype's spontaneous change in vitro. Cell differentiation status is determined by Lin28 and let-7 miRNAs in see-saw-pattern. Lin28, a repressor of let-7 and a stem cell marker, is activated by ß-catenin. The expression of ß-catenin is regulated by GSK-3ß/TGF-ß1 signaling. To understand the true role of AEC II in RILF, we freshly isolated primary AEC II directly from thoracically irradiated lungs. We then explored the expressions of cell phenotype markers and differentiation regulators in these isolated AEC II to analyze the correlation between GSK-3ß/TGF-ß1/ß-catenin signaling pathway, lin28/let-7 balance, and AEC II phenotypes at different injury phases following irradiation. Results showed that isolated single primary cells displayed AEC II ultrastructural features and proSP-C positive. The gene expressions of prosp-c (an AEC II biomarker) and hopx (an AEC I marker) significantly increased in isolated AEC II during injury repair phase (P < .001 and P < .05) but decreased at end-stage of injury, while mesenchymal markers increased in both isolated AEC II and irradiated lungs. mRNA levels of gsk-3ß, tgf-ß1, and ß-catenin increased in all irradiated AEC II, but more pronounced in the second half of injury phase (P < .05-P < .001). Similarly, the expression of lin28 was also significantly elevated in isolated AEC II at the late phase (P < .05-P < .001). Four let-7 miRNAs were significantly upregulated in all irradiated AEC II groups (P < .05-P < .001). The time-dependent and highly consistent uptrends for four lin28/let-7 ratios in sorted AEC II contrasted to downtrends in irradiated lungs. In conclusion, RILF occurred when GSK-3ß/TGF-ß1 signaling increased ß-catenin levels, which led to the augmentation of AEC II population by elevated lin28/let-7 ratio and the transcription of profibrotic cytokines and factors, thereby inducing AEC II to undergo transdifferentiation into mesenchymal cells.

The Role of RASSF1 Methylation in Lung Carcinoma.

Lung carcinoma is the most frequently diagnosed malignant neoplasms and mainly consists of small-cell lung carcinoma (SCLC) and non-small-cell lung carcinoma (NSCLC). Large number of lung carcinoma patients have poor outcomes due to the late diagnosis and the limited therapeutic options. Previous attempts have proved that the evolution of lung carcinoma is a multistep molecular aberration which various genetic or epigenetic alterations may be take part in. Among these molecular aberrations, the inactivation of tumor suppressor gene has been widely observed in all types of carcinoma including lung carcinoma. As a vital inactivated mechanism, DNA methylation of tumor suppressor gene is frequently found in lung cancer. To gain exhaustive comprehension of the carcinogenesis of lung carcinoma, we summarize our current knowledge on DNA methylation of RASSF1 (RAS-Association Domain Family 1) and its clinical significance in lung carcinoma.

Clinical Significance of P16 Gene Methylation in Lung Cancer.

Lung cancer is the leading cause of death from cancer in China. The lack of early screening technologies makes most patients to be diagnosed at advanced stages with a poor prognosis which often miss the best treatment opportunities. Thus, identifying biomarkers for minimally invasive detection and prognosis of early stage disease is urgently needed. Genetic and epigenetic alterations that promote tumorigenesis and metastasis exist in multiple cancers. These aberrant alterations usually represent early events in cancer progression suggesting their potential applications as a biomarker for cancer prediction. Studies have shown that DNA methylation is one of the key factors in progression of lung cancer. P16 promoter methylation is one of the most common epigenetic change plays a key role in lung cancer. In this review, we highlight the p16 gene methylation and its clinical significance in lung cancer.

The Role of Methylation in the CpG Island of the ARHI Promoter Region in Cancers.

Hypermethylation can downregulate many tumor suppressor gene expressions. Aplasia Ras homologue member I (ARHI, DIRAS3) is one of the maternally imprinted tumor suppressors in the RAS superfamily. This chapter overviewed the importance of ARHI methylation and expression phenomes in various types of cancers, although the exact mechanisms remain unclear. As an imprinted gene, aberrant DNA methylation of the paternal allele of ARHI was identified as a primary inhibitor of ARHI expression. The role of methylation in the CpG islands of the ARHI promoter region vary among ovarian cancers, breast cancers, hepatocellular carcinoma, colon cancers, pancreatic cancer osteosarcoma, glial tumors, follicular thyroid carcinoma, or lung cancers. The methylation of ARHI provides a new insight to understand molecular mechanisms of tumorigenesis and progression of cancers.

Effect of TCDD on the fate of epithelial cells isolated from human fetal palatal shelves (hFPECs).

Cleft palate is caused by the failure of palatal midline epithelial cells to disintegrate, which is necessary for palatal mesenchymal confluence. Although 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) exposure is linked to cleft palate at a high rate, the mechanism remains to be elucidated. The present study was designed to determine the effects of TCDD on the fate of epithelial cell isolated from human fetal palatal shelves (hFPECs). We demonstrate that TCDD increased cell proliferation and promoted the progression of cells from G1 to S phase as well as increased the number of cells entering the G2/M phase. We found that TCDD has no measurable effect on apoptosis of hFPECs. The protein level assays revealed that TCDD increased cyclin-dependent kinases 4 (cdk4), cyclin D1, cyclin E and p21 (Waf1/Cip1) but not cdk2, bcl-2, cyclin B1 and cyclin A. Furthermore, TCDD activated PI3K/AKT signaling, and the PI3K inhibitor, LY294002, partially abrogated TCDD-induced cell proliferation and gene modulations. TCDD treatment increased CYP1A1 mRNA and protein levels, which indicated the activation of AhR signaling. Knockdown of the AhR with siRNA suppressed TCDD-induced cell proliferation and PI3K/AKT signaling activation. Taken together, these data demonstrated that TCDD is able to promote growth of hFPECs through AhR-dependent activation of the PI3K/AKT pathway, which may account for the underlying mechanism by which TCDD causes a failure of palatal fusion.

TCDD promoted EMT of hFPECs via AhR, which involved the activation of EGFR/ERK signaling.

One critical step of second palatal fusion is the newly formed medial epithelia seam (MES) disintegration, which involves apoptosis, epithelial to mesenchymal transition (EMT), and cell migration. Although the environmental toxicant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) produces cleft palate at high rates, little is known about the effects of TCDD exposure on the fate of palatal epithelial cells. By using primary epithelial cells isolated from human fetal palatal shelves (hFPECs), we show that TCDD increased cell proliferation and EMT, as demonstrated by increased the epithelial markers (E-cadherin and cytokeratin14) and enhanced the mesenchymal markers (vimentin and fibronectin), but had no effect on cell migration and apoptosis. TCDD exposure led to a dose-dependent increase in Slug protein expression. Coimmunoprecipitation revealed that TCDD promoted AhR to form a protein complex with Slug. ChIP assay confirmed that TCDD exposure recruited AhR to the xenobiotic responsive element of Slug promoter. Knockdown of AhR by siRNA remarkably weakened TCDD-induced binding of AhR to the XRE promoter of slug, thereby suppressed TCDD-induced vimentin. Further experiment showed that TCDD stimulated EGFR phosphorylation did not influence the TGFß3/Smad signaling; whereas TCDD increased phosphorylation of ERK1/2 and p38 with no effect on activation of JNK. By using varieties of inhibitors, we confirmed that TCDD promoted proliferation and EMT of hFPECs via activation of EGFR/ERK pathway. These data make a novel contribution to the molecular mechanism of cleft palate by TCDD.

Excessive retinoic acid impaired proliferation and differentiation of human fetal palatal chondrocytes (hFPCs).

Chondrocyte proliferation and differentiation is a fundamental process during hard palatogenesis. Excessive retinoic acid (RA), the biologically most active metabolite of vitamin A, has been reported to adversely affect chondrogenesis. The aim of this study was to investigate the mechanisms underlying RA-induced chondrocyte differentiation by using human fetal palatal chondrocytes (hFPCs) aging about 9 weeks of amenorrhea. RA treatment inhibited proliferation and induced apoptosis in hFPCs. Alkaline phosphatase activity assay, quantitative alcian blue staining, and real-time PCR analysis revealed that RA treatment stimulated hFPCs to undergo maturation and terminal differentiation, as demonstrated by decreased chondrogenic markers and increased osteogenic markers. Further studies demonstrated that RA treatment increased Wnt/ß-catenin signaling, as demonstrated by Wnt/ß-catenin target gene expression analysis and a luciferase-based ß-catenin-activated reporter assay. To address the role of Wnt/ß-catenin signaling, we treated hFPCs with Dickkopf-related protein 1, an extracellular inhibitor of Wnt/ß-catenin signaling, and the observed all-trans retinoic acid-mediated increases in nuclear accumulation of ß-catenin, alkaline phosphatase activity, and type I collagen mRNA were attenuated, suggesting that RA modulated Wnt signaling at ligand-receptor level. In summary, excessive all-trans retinoic acid inhibited proliferation and promoted ossification of hFPCs by upregulation of Wnt/ß-catenin signaling.

Negative interplay of retinoic acid and TGF-ß signaling mediated by TG-interacting factor to modulate mouse embryonic palate mesenchymal-cell proliferation.

Mesenchymal-cell proliferation is the main process in shelf outgrowth. Both all-trans-retinoic acid (atRA) and transforming growth factor-ß3 (TGF-ß3) play an important role in mouse embryonic palate mesenchymal (MEPM) cell proliferation. In the present study, we investigated the crosstalk between RA and TGF-ß signaling in MEPM-cell proliferation. We found that atRA inhibited MEPM-cell proliferation by downregulating TGF-ß/Smad signaling and that TGF-ß3 treatment was able to antagonize RA signaling. Transforming growth-interacting factor (TGIF) is a transcriptional repressor that suppresses both TGF-ß- and retinoid-driven gene transcription. Furthermore, we investigated the role of TGIF in the interaction between both TGF-ß and RA signaling in MEPM-cell proliferation. The results showed that both atRA and TGF-ß3 significantly increased the expression level of TGIF, and TGIF mediated the negative interaction between TGF-ß and RA signaling pathways, which depended on TGIF binding to Smad2 or RARß (RA receptor beta). Moreover, after deletion of TGIF, both the effects of atRA on TGF-ß-dependent protein expression and the effects of TGF-ß on RA-dependent protein expression were lost. So we conclude that there is a negative functional interplay of RA and TGF-ß signaling mediated by TGIF to modulate MEPM-cell proliferation.

Identification of competing endogenous RNA networks associated with circRNA and lncRNA in TCDD-induced cleft palate development.

2,3,7,8 -tetrachlorodibenzo-p-dioxin (TCDD) is a teratogen that can induce cleft palate formation, a common birth defect. Competing endogenous RNAs (ceRNAs), including circular RNAs (circRNAs) and long non-coding RNAs (lncRNAs), indirectly regulate gene expression via sharing microRNAs (miRNAs). Nevertheless, the mechanism by which they act as ceRNAs to regulate palatal development remains to be explored in greater detail. Here, the cleft palate model of C57BL/6 N pregnant mice was constructed by gavage of TCDD (64 ug/kg) on gestation day (GD) 10.5, and the palatal shelves were taken on gestation day (GD) 14.5 for whole-transcriptome sequencing to investigate the underlying mechanisms of the roles of circRNAs and lncRNAs as ceRNAs in cleft palate. Sequencing results revealed that 293 lncRNA, 589 circRNA, 47 miRNA, and 138 messenger RNA (mRNA) were significantly dysregulated, and the cytochrome P450 (CYP) enzymes and the aryl hydrocarbon receptor (AhR) pathway play key roles in the induction of cleft palate upon exposure to TCDD. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed the function of TCDD function was mainly related to the metabolic processes of intracellular compounds, including the metabolic processes of cellular aromatic compounds and the metabolism of exogenous drugs by cytochrome P450, etc. Furthermore, quantitative reverse transcription polymerase chain reaction (qRT-PCR) indicated that the circRNA_1781/miR-30c-1-3p/PKIB and XR_380026.2/miR-1249-3p/DNAH10 ceRNA networks were hypothesized to be a hub involved in palatal development suggesting that the circRNA_1781/miR-30c-1-3p/PKIB and XR_380026.2/miR-1249-3p/DNAH10 ceRNA networks may be critical for palatogenesis, setting the foundation for the investigation of cleft palate.

AKT/mTOR-mediated autophagic signaling is associated with TCDD-induced cleft palate.

In utero exposure to the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) can contribute to high rates of cleft palate (CP) formation, but the mechanistic basis for these effects remains uncertain. Here, multi-omics-based metabolomic and transcriptomic analyses were employed to characterize the etiological basis for TCDD-induced CP on gestational day 14.5 (GD14.5). These analyses revealed that TCDD-induced CP formation is associated with calcium, MAPK, PI3K-Akt, and mTOR pathway signaling. PI3K-Akt and mTOR signaling activity is closely linked with the maintenance of cellular proliferation and survival. Moreover, mTOR-mediated regulation of autophagic activity is essential for ensuring an appropriate balance between metabolic activity and growth. Murine embryonic palatal mesenchymal (MEPM) cell proliferation was thus characterized, autophagic activity in these cells was evaluated through electron microscopy and western immunoblotting was used to compare the levels of autophagy- and AKT/mTOR-related protein between the control and TCDD groups on GD14.5. These analyses indicated that MEPM cell proliferative and autophagic activity was inhibited in response to TCDD exposure with the concomitant activation of AKT/mTOR signaling, in line with the multi-omics data. Together, these findings suggested that following TCDD exposure, the activation of AKT/mTOR-related autophagic signaling may play a role in the loss of appropriate palatal cell homeostasis, culminating in the incidence of CP.

Upregulated LncRNA-Meg3 modulates the proliferation and survival of MEPM cells via interacting with Smad signaling in TCDD-induced cleft palate.

Exposure to the environmental contaminant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in utero can result in high rates of cleft palate (CP) formation, yet the underlying mechanisms remain to be characterized. In vivo, the lncRNA Meg3 was upregulated following TCDD treatment in CP-associated murine embryonic palatal tissue, with concomitant changes in proliferative and apoptotic activity in these murine embryonic palatal mesenchymal (MEPM) cells. Meg3 can modulate the TGF-ß/Smad to control the proliferation, survival, and differentiation of cells. Accordingly, TCCD and TGF-ß1 were herein used to treat MEPM cells in vitro, revealing that while TCDD exposure altered the proliferative activity and apoptotic death of these cells, exogenous TGF-ß1 exposure antagonized these effects via TGF-ß/Smad signaling. TCDD promoted Meg3 upregulation, whereas TGF-ß1 suppressed TCDD-driven upregulation of this lncRNA. Meg3 was additionally determined to directly interact with Smad2, with significant Meg3 enrichment in Smad2-immunoprecipitates following TCDD treatment. When Meg3 was silenced, the impact of TCDD on Smad signaling, proliferative activity, and apoptosis were ablated, while the effects of exogenous TGF-ß1 were unchanged. This supports a model wherein Meg3 is upregulated in TCDD-exposed palatal tissue whereupon it can interact with Smad2 to suppress Smad-dependent signaling, thus controlling MEPM cell proliferation and apoptosis, contributing to TCDD-induced CP, which provides a theoretical support for the precautions of cleft palate induced by TCDD.

SFXN1-mediated immune cell infiltration and tumorigenesis in lung adenocarcinoma: A potential therapeutic target.

BACKGROUND: Sideroflexin 1 (SFXN1), a mitochondrial serine transporter implicated in one-carbon metabolism, is a prognostic biomarker in lung adenocarcinoma (LUAD). However, its role in LUAD progression remains elusive. This study aimed to investigate the functional significance of SFXN1 in LUAD and evaluate its potential as a therapeutic target. METHODS: We analyzed SFXN1 expression and its diagnostic and prognostic value in LUAD using the Pan-cancer TCGA dataset. In vitro assays (CCK-8, cell cycle, EDU, wound-healing, and transwell) were employed to assess the role of SFXN1, complemented by in vivo experiments. RNA sequencing elucidated SFXN1-mediated cellular functions and potential mechanisms. Bulk RNA-seq and scRNA-seq data from TCGA and GEO were used to investigate the correlation between SFXN1 and the tumor immune microenvironment. RT-qPCR, Western blot, and IHC assays validated SFXN1 expression and its impact on the immune microenvironment in LUAD. RESULTS: SFXN1 was upregulated in LUAD tissues and associated with poor prognosis. RNA-seq and scRNA-seq analyses revealed increased SFXN1 expression in tumor cells, accompanied by decreased infiltration of NK and cytotoxic T cells. SFXN1 knockdown significantly reduced cell proliferation and migration, and the inhibition of ERK phosphorylation and CCL20 expression may be the molecular mechanism involved. In vivo, targeting SFXN1 decreased Tregs infiltration and inhibited tumor growth. CONCLUSIONS: Our findings suggest that SFXN1 may be a potential therapeutic target for LUAD treatment.

Associations between the proliferation of palatal mesenchymal cells, Tgfß2 promoter methylation, Meg3 expression, and Smad signaling in atRA-induced cleft palate.

All-trans retinoic acid (atRA) is a teratogen that can induce cleft palate formation. During palatal development, murine embryonic palate mesenchymal (MEPM) cell proliferation is required for the appropriate development of the palatal frame, with Meg3 serving as a key regulator of the proliferative activity of these cells and the associated epithelial-mesenchymal transition process. DNA methylation and signaling via the TGFß/Smad pathway are key in regulating embryonic development. Here, the impact of atRA on MEPM cell proliferation and associations between Tgfß2 promoter methylation, Meg3, and signaling via the Smad pathway were explored using C57BL/6 N mice treated with atRA (100 mg/kg) to induce fetal cleft palate formation. Immunohistochemistry and BrdU assays were used to detect MEPM proliferation and DNA methylation assays were performed to detect Tgfß2 promoter expression. These analyses revealed that atRA suppressed MEPM cell proliferation, promoted the upregulation of Meg3, and reduced the levels of Smad2 and Tgfß2 expression phosphorylation, whereas Tgfß2 promoter methylation was unaffected. RNA immunoprecipitation experiments indicated that the TgfßI receptor is directly targeted by Meg3, suggesting that the ability of atRA to induce cleft palate may be mediated through the Tgfß/Smad signaling pathway.

Dynamic changes in ambient PM2.5 and body mass index among old adults: a nationwide cohort study.

Outdoor air pollution has been considered as a severe environmental health issue that almost affecting everyone in the world, and intensive actions were launched. However, little is known about the association between dynamic changes in ambient fine particulate matter (PM2.5) exposure and body mass index (BMI) among old adults. To investigate the dynamic changes in ambient PM2.5 and body mass index among the elderly, we included a total of 7204 participants from 28 provinces of China during 2011-2015 in the China Health and Retirement Longitudinal Study (CHARLS). Ambient fine particle matter (PM2.5) was estimated using a well-validated space-time extremely randomized trees model. Change in PM2.5 and BMI (ΔPM2.5 and ΔBMI) were calculated as the value at a follow-up visit minus value at baseline. Linear mixed-effects models were applied to quantify the associations, controlling for sociodemographic factors. We found that per 1 µg/m3 increase in PM2.5 exposure was associated with a 0.031-0.044 kg/m2 increase in BMI among the elderly. We observed an approximate linear concentration-response relationship of PM2.5 and BMI in each visit. Each 1 µg/m3 increase in ΔPM2.5 exposure was associated with an increase in ΔBMI (ß = 0.040, 95% CI 0.030, 0.049), while per 1 µg/m3 decrease in the ΔPM2.5 exposure level was associated with a decrease in ΔBMI (ß = -0.016, 95% CI -0.027, -0.004). Our findings suggest that dynamic changes in ambient PM2.5 was positively associated with changes in BMI among old Chinese population.

Sex Specificity in the Mixed Effects of Blood Heavy Metals and Cognitive Function on Elderly: Evidence from NHANES.

The way that males and females react to environmental exposures and negative impacts on their neurological systems is often different. Although previous research has examined the cognitively impairing effects of solitary metal exposures, the relationship between metal mixtures and cognitive function, particularly when considering an individual's sex, remains elusive. This study aimed to investigate the sex differences in the association between multiple metal combinations and cognitive function in older Americans. This research employed the 2011-2014 NHANES survey of elderly Americans. The association between five mixed metals and four cognitive tests (the animal fluency test (AFT), the digit symbol substitution test (DSST), the instant recall test (IRT), and the delayed recall test (DRT)) were investigated with generalized linear regression model (GLM), Bayesian kernel machine regression model (BKMR), weighted quantile sum regression model (WQS), and quantile g-computation regression model (Qgcomp). A total of 1833 people, including 883 males and 950 females, enrolled in this cross-sectional study. We discovered that blood lead and blood cadmium were negatively associated with cognitive performance, while blood selenium demonstrated a positive association with cognitive function in older people. The negative relationship of heavy metal combinations on cognitive function might be somewhat reduced or even reversed via selenium. The IRT, AFT, and DSST are three of the four cognitive tests where men had more dramatic positive or negative results. There was a sex-specific connection between blood metal ratios and cognitive function among older Americans, as evidenced by the more significant relationship between mixed metals and cognitive performance in men (either positively or negatively). These results emphasize the impacts of ambient heavy metal exposure on cognitive function by employing sex-specific methods.

Fasting Insulin and Risk of Overall and 14 Site-Specific Cancers: Evidence From Genetic Data.

Objective: Whether fasting insulin (FI) plays a role in cancer risk remains unclear. This study aimed to investigate the association between FI and cancer risk and to explore its potential mediator role in the association between type 2 diabetes mellitus (T2DM) and cancer. Methods: Two-sample Mendelian randomization (TSMR) analysis was performed to evaluate the effect of FI on overall and 14 site-specific cancers using genome-wide association study (GWAS) summary-level data from Meta-Analyses of Glucose and Insulin-related traits Consortium (MAGIC) and consortia of 14 site-specific cancers. The primary MR approach was conducted by using the random-effect inverse-variance weighted (IVW) method, and sensitivity analyses were implemented by adopting weighted-median, weighted-mode, MR-Egger, and MR-PRESSO tests. Polygenic risk score analysis was executed by using individual-level data from UK Biobank to validate the findings from TSMR analyses. Multivariable Mendelian randomization (MVMR) was carried out to estimate the mediation effect of FI on the association between T2DM and cancer. Results: TSMR study suggested that genetically determined high FI levels were associated with increased risk of colorectal cancer (odds ratio (OR) = 1.87, 95% CI: 1.23-2.84, p = 0.003) and endometrial cancer (OR = 1.89, 95% CI: 1.08-3.01, p = 0.008), but not associated with overall cancer risk or the other 12 studied cancer sites. Polygenic risk score analysis successfully replicated the association between genetic liability to high FI levels and the increased risk of colorectal and endometrial cancers. MVMR and MR mediation analyses detected an intermediary effect of FI and quantified that FI mediated 21.3% of the association between T2DM and endometrial cancer. Conclusions: This study demonstrated that FI levels are associated with the risk of colorectal and endometrial cancers, and FI was found to play an intermediary role in the association between T2DM and endometrial cancer. The associations between FI and other cancers need to be further studied.