Search

Carotid plaque is one of the typical manifestations and precursors of diabetic cardiovascular complications. As a new adipokine, asprosin participates in the development of diabetes and cardiovascular diseases, and is considered to be closely related to insulin resistance and glucolipid metabolism. This study aimed to analyze the relationship between serum asprosin level and carotid plaque in patients with type 2 diabetes mellitus (T2DM).A total of 180 patients with T2DM were selected. The basic parameters and biochemical indexes of the subjects were measured, and the serum asprosin concentration of the subjects was detected by ELISA. The carotid plaque was evaluated by color Doppler ultrasound.The level of serum asprosin in the T2DM with carotid plaque group was significantly higher than that in T2DM without carotid plaque group [2.53(1.73-3.21) vs 1.72(1.23-2.34) ng/mL, P 0.05]. The incidence of carotid plaque in the low, middle and high quartiles was 31.7 %, 48.3 % and 70 % respectively. Correlation analysis showed that serum asprosin was positively correlated with BMI, WHR, SBP, DBP, FIns, LDL-C, HOMA-IR, and HOMA-β (P 0.05). Linear regression analysis showed that WHR, DBP, FIns, and LDL-C were independent influencing factors of asprosin. Logistic regression analysis showed that serum asprosin was still significantly correlated with carotid plaque in T2DM patients after adjusting for multiple confounding factors. The area under receiver-operating curve (ROC) of asprosin predicting carotid plaque was 0.701 (0.625-0.777) in T2DM.The level of serum asprosin in T2DM patients with carotid plaques is significantly higher, suggesting that asprosin may play a role in the occurrence and development of carotid plaques in T2DM. Detection of this index can provide new clinical evidence for the prevention and treatment of diabetic cardiovascular disease.

Although the overall survival rate of B cell acute lymphoblastic leukemia (B-ALL) in childhood is more than 80%, it is merely 30% in refractory/relapsed and adult patients with B-ALL. This demonstrates a need for improved therapy targeting this subgroup of B-ALL. Here, we show that the ten-eleven translocation 1 (TET1) protein, a dioxygenase involved in DNA demethylation, is overexpressed and plays a crucial oncogenic role independent of its catalytic activity in B-ALL. Consistent with its oncogenic role in B-ALL, overexpression of TET1 alone in normal precursor B cells is sufficient to transform the cells and cause B-ALL in mice within 3 to 4 months. We found that TET1 protein is stabilized and overexpressed because of its phosphorylation mediated by protein kinase C epsilon (PRKCE) and ATM serine/threonine kinase (ATM), which are also overexpressed in B-ALL. Mechanistically, TET1 recruits STAT5B to the promoters of CD72 and JCHAIN and promotes their transcription, which in turn promotes B-ALL development. Destabilization of TET1 protein by treatment with PKC or ATM inhibitors (staurosporine or AZD0156; both tested in clinical trials), or by pharmacological targeting of STAT5B, greatly decreases B-ALL cell viability and inhibits B-ALL progression in vitro and in vivo. The combination of AZD0156 with staurosporine or vincristine exhibits a synergistic effect on inhibition of refractory/relapsed B-ALL cell survival and leukemia progression in PDX models. Collectively, our study reveals an oncogenic role of the phosphorylated TET1 protein in B-ALL independent of its catalytic activity and highlights the therapeutic potential of targeting TET1 signaling for the treatment of refractory/relapsed B-ALL.

This study investigated the role of N6-methyladenosine RNA methylation in liver regeneration following partial hepatectomy in mice. We created a liver-specific knockout mouse model by the deletion of Mettl3, a key component of the N6-methyladenosine methyltransferase complex, using the albumin-Cre system. Mettl3 liver-specific knockout mice and their wild-type littermates were subjected to 2/3 partial hepatectomy. Transcriptomic changes in liver tissue at 48 h after partial hepatectomy were detected by RNA-seq. Immunohistochemistry and immunofluorescence were used to determine protein expression levels of Ki67, hepatocyte nuclear factor 4 alpha, and cytokeratin 19. Terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick-end labeling was also performed. Liver weight/body weight ratios after partial hepatectomy were significantly lower in Mettl3 liver-specific knockout mice than in wild-type mice at 48 h after 2/3 partial hepatectomy (3.1% ± 0.11% vs. 2.7% ± 0.03%). Compared with wild-type littermates, Mettl3 liver-specific knockout mice showed reduced bromodeoxyuridine staining and reduced Ki-67 expression at 48 h after 2/3 partial hepatectomy. RNA-seq analysis showed that Mettl3 liver-specific knockout delayed the cell cycle progression in murine liver by downregulating the expression levels of genes encoding cyclins D1, A2, B1, and B2. Loss of Mettl3-mediated N6-methyladenosine function led to attenuated liver regeneration by altering the mRNA decay of suppressor of cytokine signaling 6, thereby inhibiting the phosphorylation of signal transducer and activator of transcription 3 during early liver regeneration. These results demonstrated the importance of N6-methyladenosine mRNA modification in liver regeneration and suggest that Mettl3 targeting might facilitate liver regeneration.

METTL16 has recently been identified as an RNA methyltransferase responsible for deposition of N(6)-methyladenosine (m(6)A) in a few transcripts. Whether METTL16 methylates a large set of transcripts, similar to METTL3 and METTL14, remains unclear. Here we show that METTL16 exerts both methyltransferase activity-dependent and -independent functions in gene regulation. In cell nucleus, METTL16 functions as an m(6)A writer to deposit m(6)A into hundreds of its specific mRNA targets. In cytosol, METTL16 promotes translation in an m(6)A-independent manner. More specifically, METTL16 directly interacts with eukaryotic initiation factor 3a/b (eIF3a/b) and ribosomal RNAs (rRNAs) through its Mtase domain, thereby facilitating the assembly of the translation initiation complex (TIC) and promoting translation of over 4,000 mRNA transcripts. Moreover, we demonstrate that METTL16 is critical for the tumorigenesis of hepatocellular carcinoma. Collectively, our studies reveal previously unappreciated dual functions of METTL16 as an m(6)A writer and a translation initiation facilitator, which together contribute to its essential function in tumorigenesis.

Patients with hepatocellular carcinoma (HCC) suffer from few treatment options and poor survival rates. Here we report that endonuclease VIII-like protein 3 (NEIL3) is overexpressed in HCC and correlates with poor survival. All six HCC cell lines investigated were dependent on NEIL3 catalytic activity for survival and prevention of senescence, while NEIL3 was dispensable for nontransformed cells. NEIL3-depleted HCC cell lines accumulated oxidative DNA lesions specifically at telomeres, resulting in telomere dysfunctional foci and 53BP1 foci formation. Following oxidative DNA damage during mitosis, NEIL3 relocated to telomeres and recruited apurinic endonuclease 1 (APE1), indicating activation of base excision repair. META-FISH revealed that NEIL3, but not NEIL1 or NEIL2, is required to initiate APE1 and polymerase beta (POLB)-dependent base excision repair at oxidized telomeres. Repeated exposure of NEIL3-depleted cells to oxidizing damage induced chromatin bridges and damaged telomeres. These results demonstrate a novel function for NEIL3 in repair of oxidative DNA damage at telomeres in mitosis, which is important to prevent senescence of HCC cells. Furthermore, these data suggest that NEIL3 could be a target for therapeutic intervention for HCC.Significance:This study describes compartmentalization of base excision repair during mitosis that is dependent on NEIL3, APE1, and POLB to repair oxidative damage accumulating at telomeres in hepatocellular carcinoma.

Supplementary Data from NEIL3 Prevents Senescence in Hepatocellular Carcinoma by Repairing Oxidative Lesions at Telomeres during Mitosis

Global biodiversity is declining at an unprecedented rate, and the Post-2020 Global Biodiversity Framework requires each country to fulfill the conservation targets in biodiversity-inclusive spatial planning. Croplands provide habitat and food for many species, making them crucial for biodiversity conservation in addition to food production. Assessing conservation priorities in cropland is a prerequisite to allocate conservation resources and plan actions for better conservation outcomes. Yet quantitative methods to assess cropland conservation priority for biodiversity conservation at a national scale are still lacking. We proposed a framework for identifying the conservation priority in cropland for bird species at a national scale and applied the framework in China. We calculated the suitable habitat for each species and used a complementarity-based approach to designate the irreplaceable conservation priority areas considering richness, threatened level, and conservation percentage targets. We identified cropland taking up 6.76% of China's land area as a bird conservation priority, partially covering the suitable habitat of all the study species. By analyzing the landscape pattern of the priority areas and species' foraging traits, we provided policy-making suggestions according to area-specific characteristics. This framework can be used to identify priority areas for large-scale biodiversity conservation for different countries.

Tsukushi (TSK), a novel hepatokine, has recently been pointed out to play an important role in energy homeostasis and glycolipid metabolism. However, there are no clinical studies on the association of TSK with metabolic syndrome (MetS), the typical constellation of metabolic disorders. This study was conducted to explore the relationship between TSK and MetS as well as each of its metabolic component clinically.We analyzed in this cross-sectional study serum TSK levels by ELISA in 392 participants, including 90 non-MetS and 302 MetS, to compare TSK in two groups and in different numbers of metabolic components. The odds ratios (OR) of TSK quartile in MetS and each metabolic component were computed by multivariate logistic regression analysis.TSK was substantially higher in MetS than in non-MetS subjects (P 0.001). TSK increased with the concomitant increase of the number of metabolic components (P for0.001). Logistic regression analyses demonstrated that the OR of MetS was 2.74 for the highest versus the lowest quartile of TSK (P 0.001) after adjusting for age, gender, smoking status, alcohol consumption and medication use. Additionally, TSK was associated with the OR of poor HDL-C and elevated fasting glucose (P 0.05).Circulating TSK was higher in MetS patients and linked with MetS risk, suggesting that TSK may play a role in the genesis of MetS and be a potential therapeutic target for MetS. Future study should investigate the connection between TSK levels and MetS pathogenesis.

Background/aim: Previous studies have suggested that the hepatic steatosis index (HSI) and fatty liver index (FLI) can be used as a predictor of non-alcoholic fatty liver disease (NAFLD). The aim of our study was to determine whether non-invasive indices of hepatic steatosis (HSI and FLI) are associated with carotid atherosclerosis in type 2 diabetes mellitus (T2DM). Methods: This was a cross-sectional study conducted in the T2DM patients (n=768). Carotid intima-media thickness (CIMT) was measured by the Color Doppler ultrasound. The HSI was calculated based on gender, body mass index (BMI), and transaminases level. The FLI was based on BMI, waist circumference (WC), triacylglycerols (TG) and g-glutamyl transferase (GGT). Results: Raised HSI and FLI levels was associated with increased CIMT levels in T2DM patients. Patients with greater CIMT had higher HSI (39.10 ± 5.70 vs 36.10 ± 4.18, P < 0.001) and FLI (46.35 (29.96, 65.54) vs 36.93 (18.7, 57.93), P < 0.001) than those with lower CIMT. Subjects with existing carotid plaque had higher HSI (38.28 ± 5.63 vs 35.69 ± 3.45 P < 0.001) and FLI (47.41 (27.77, 66.62) vs 37.19 (17.71, 51.78), P < 0.001) accordingly. HSI (r = 0.343, P < 0.001) and FLI (r = 0.184, P < 0.001) were positively related with the CIMT. In the linear regression, after full adjustment metabolic risk factors, smoking, and measures of insulin resistance, HSI and FLI were independently associated with CIMT (HSI: β = 0.011, FLI: β = 0.001, all P < 0.01). Further, logistic regression analyses showed that higher HSI and FLI had an impact on the risk for carotid atherosclerosis [HSI: OR (95%CI): 1.174 (1.123-1.228), FLI: OR (95%CI): 1.011(1.004-1.019), all P < 0.01]. Overall, increasing values of HSI and FLI were associated with CIMT (P < 0.05) significantly across different categories of age and hypertension. Conclusion: Current data suggest HSI and FLI are independently correlated with carotid atherosclerosis in T2DM. They may be a simple and useful marker for assessing the progression of diabetic macrovascular complications.

Aim We detected whether serum asprosin levels play a role in the occurrence and development of albuminuria in patients with type 2 diabetes mellitus (T2DM), which has not been previously discussed. Methods Based on urinary albumin/creatinine ratio (UACR), 207 T2DM patients were divided into T2DM patients with normoalbuminuria (UACR

Aim ANGPTL8 is a cytokine expressed and secreted by liver and adipose tissue, and is involved in glucose, lipid, and energy metabolism. Although studies have shown that ANGPTL8 is elevated in type 2 diabetes mellitus (T2DM) and cardiovascular disease, few have examined the association between ANGPTL8 single-nucleotide polymorphisms and the risk of macrovascular complications in T2DM patients. This study aimed to explore the relationship between rs2278426 and carotid intima-media thickening (cIMT) in T2DM. Methods A total of 217 T2DM patients and 201 healthy control subjects with normal glucose tolerance were recruited in the study. T2DM patients were divided into two groups: T2DM patients without cIM thickening (cIMT

Background This study was conducted in patients with type 2 diabetes mellitus (T2DM) to assess the association between visceral fat area (VFA) and cardiac hemodynamics. Methods A total of 568 patients with type 2 diabetes (mean age 54±12 years; 40.8% of women) were enrolled. Visceral fat area (VFA, m2) and subcutaneous fat area (SFA, m2) were evaluated by a bioelectrical impedance analyzer. Cardiac hemodynamics were measured by echocardiography, and other clinical and laboratory variables were also assessed and recorded. Patients were divided into those with VFA ≤ 100 (n=369) and those with VFA > 100 (n=199). Results VFA, SFA, LVMI (left ventricular mass index), left atrial diameter, left ventricular diastolic diameter (LvDd), interventricular septal thickness (IVST), left ventricular systolic diameter (LvSd), and posterior wall thickness (PWT) levels in high-V groups were significantly higher than those in low-V groups. Correlation analysis showed that VFA was positively correlated with LVMI (r=0.120, p=0.004), LVM (r=0.249, p

Purpose Triglyceride-glucose (TyG) index is a reliable and inexpensive alternative indicator of insulin resistance. Previous studies have shown that elevated TyG index increases the risk of diabetes, coronary heart disease, and other diseases, but the relationship between TyG index and cardiac hemodynamics in patients with type 2 diabetes mellitus (T2DM) is not clear. This study was conducted in patients with T2DM to assess the relationship between TyG and cardiac hemodynamics and its predictive ability for T2DM. Methods A total of 647 individuals (348 males and 299 females) were enrolled in this study, including 446 T2DM patients and 201 healthy controls. The clinical data and related laboratory variables were assessed and recorded, and TyG index was calculated. Cardiac hemodynamics was measured by echocardiography. Pearson or Spearman correlation analysis and linear regression analysis were conducted to explore the association between TyG and cardiac hemodynamics. The receiver operating characteristics (ROC) curve was used to evaluate the efficacy of TyG index in the diagnosis of T2DM. Results Compared with healthy controls, the systolic blood pressure (SBP), body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), HOMA-IR, and TyG levels were higher in patients with T2DM. With the increase of TyG, the levels of left ventricular mass index (LVMI), left ventricular mass (LVM), left ventricular end diastolic diameter (LVDd), posterior wall thickness (PWT), and interventricular septum thickness (IVST) were also increased in T2DM individuals. Multivariate linear regression analysis showed that TyG was an independent determinant of LVEF, PWT, IVST, and ejection time (ET) after adjusting for confounding factors. In addition, individuals with visceral obesity had higher TyG and TyG can be used as a predictor of T2DM with an AUC of 0.903 (95% CI:0.879–0.927). Conclusions The increase of TyG index is closely related to cardiac hemodynamics of T2DM patients, which is expected to be a simple and practical biological index to predict the changes of cardiac function in patients with T2DM.

RNABy analyzing The Cancer Genome Atlas (TCGA) dataset, we found that elevated expression ofWe show that YTHDC1 plays a critical oncogenic role in TNBC metastasis through promoting the nuclear export and expression of

N

As the most biodiversity-rich part of the protected areas system, habitats within the pilot national parks have long been threatened by drastic human-induced land use and land cover changes. The growing concern about habitat loss has spurred China's national park project to shift from pilot to construction phase with the official establishment of China's first group of national parks (CFGNPs) in October 2021. But far too little attention has been paid to the synergistic work concerning the habitat quality (HQ) dynamics of all five national parks. Here, the InVEST model, combined with a satellite-derived land use and land cover product and a hot spot analysis (HSA) method, was used to investigate the HQ dynamics at the park- and pixel-scale within the CFGNPs. Our results demonstrate that the past ecological conservation practices within national parks have been unpromising, especially in Giant Panda National Park, Northeast China Tiger and Leopard National Park (NCTL), and Wuyi Mountain National Park (WYM), where HQ as a whole showed a significant decline. Furthermore, more than half of Hainan Tropical Rainforest National Park (87.2%), WYM (77.4%), and NCTL (52.9%) showed significant HQ degradation from 1980 to 2019. Besides, increasing trends in the area shares of HQ degraded pixels were observed in all five national parks from 1980-1999 to 2000-2019. The HSA implied that the hot spots of high HQ degradation rates tend to occur in areas closer to urban settlements or on the edge of national parks, where human activities are intensive. Despite these disappointing findings, we highlighted from the observed local successes and the HQ plateau that the construction of CFGNPs is expected to reverse the deteriorating HQ trends. Thus, we concluded our paper by proposing an HSA-based regulatory zoning scheme that includes five subzones to guide the future construction of China's national park system.

The ATP binding cassette (ABC) transporter family is ubiquitous in eukaryotes, specifically in vertebrates, and plays a crucial role in energy homeostasis, cell signaling, and drug resistance. Accumulating evidence indicates that some ABC transporters contribute to cancer cell proliferation and tumor progression; however, relatively little is known about the behavior of the ABC transporter family in hepatocellular carcinoma (HCC). By analyzing two public transcriptomic databases, we evaluated the effect of genes in the ABC transporter family on HCC prognostic prediction; ABCC6 was selected for further study. Notably, ABCC6 was found to be downregulated in HCC tissues and correlated with favorable outcomes in patients with HCC. Moreover, ABCC6 knockdown not only significantly promoted cell proliferation in vitro and in vivo, but also inhibited cell cycle arrest and cell apoptosis. Transcriptome analysis revealed that ABCC6 depletion enhanced the “mitotic cell cycle” and “DNA replication” pathways, and suppressed the “PPAR signaling pathway”. Further investigation demonstrated that PPARα, one of the key regulators in peroxisome metabolism, is located downstream of ABCC6. In summary, our study provides profound insights into the behavior of ABC transporter family genes in various HCC cohorts, identifies ABCC6 as a biomarker for early-stage HCC diagnosis, and offers experimental basis for further investigations of targeting ABCC6 in the treatment of patients with HCC.

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease with increasing prevalence worldwide. Angiopoietin-like protein 8 (ANGPTL8), a member of the angiopoietin-like protein family, is involved in glucose metabolism, lipid metabolism, and energy homeostasis and believed to be associated with T2DM. Expression levels of ANGPTL8 are often significantly altered in metabolic diseases, such as non-alcoholic fatty liver disease (NAFLD) and diabetes mellitus. Studies have shown that ANGPTL8, together with other members of this protein family, such as angiopoietin-like protein 3 (ANGPTL3) and angiopoietin-like protein 4 (ANGPTL4), regulates the activity of lipoprotein lipase (LPL), thereby participating in the regulation of triglyceride related lipoproteins (TRLs). In addition, members of the angiopoietin-like protein family are varyingly expressed among different tissues and respond differently under diverse nutritional and metabolic status. These findings may provide new options for the diagnosis and treatment of diabetes, metabolic syndromes and other diseases. In this review, the interaction between ANGPTL8 and ANGPTL3 or ANGPTL4, and the differential expression of ANGPTL8 responding to different nutritional and metabolic status during the regulation of LPL activity were reviewed.

Background Ectodysplasin A (EDA), a new hepatokine, has been recently characterized to play a role in liver lipid metabolism and insulin resistance, but its physiological role remains scarcely acquainted in obesity. This study was the first time to determine the level of serum EDA in obesity, and to assess change in the levels of EDA after weight loss in obese mice.Methods We analyzed the serum concentrations of EDA by enzyme-linked immunosorbent assay (ELISA) in 60 subjects including 30 normal weight and 30 obesity. Male C57BL/6J mice were fed with high-fat diet and injected by liraglutide to reduce weight. AML12 cells were induced by palmitic acid and treated with liraglutide. Quantitative real-time PCR and Western blot analysis were conducted to evaluate the expression of EDA. Results Serum EDA levels were significantly higher in obesity than in normal weight subjects. It was positively correlated with body mass index (BMI). More importantly, the mRNA and protein expression of EDA reduced after liraglutide management in vivo and in vitro.Conclusions The level of EDA increased significantly in obesity and decreased significantly after weight loss. It is suggested that EDA may be a novel hepatokine associated with obesity-related metabolic diseases.

BACKGROUNDEtodysplasin A (EDA), a newly discovered hepatokine, has recently been considered to be closely related to glycolipid metabolism disorders, but the pathophysiological effects of EDA are still poorly understood. This study was the first time to determine the level of serum EDA in newly diagnosed type 2 diabetes mellitus (T2DM) patients, and to explore the relationships between serum EDA levels and various metabolic indexes.METHODS A total of 184 subjects were enrolled in the study, including 92 subjects with newly diagnosed T2DM and 92 subjects with age- and sex- matched normal glucose tolerance (NGT). Serum EDA levels were determined using enzyme-linked immunosorbent assay (ELISA). And oral glucose tolerance test, glycosylated hemoglobin c(HbA1c), blood lipid and insulin were also measured. Insulin resistance (IR) and islet β-cell function were assessed by homeostasis model assessment (HOMA).RESULTSSerum EDA levels were significantly increased in the T2DM group than in the NGT group (359.91 ± 117.99 vs. 265.82 ± 86.51pg/mL, PPPPCONCLUSIONS Serum EDA level are significantly higher in T2DM patients, indicating that circulating EDA may be involved in the pathogenesis of T2DM.

Tsukushi (TSK), a newly identified hepatokine, is a member of the small leucine-rich proteoglycans (SLRPs) family. TSK was originally isolated and identified in the lens of the chicken. Preliminary research on TSK has focused on its role in various physiological processes such as growth and development, wound healing, and cartilage formation. In recent years, the role of TSK in regulating cell signaling pathways, cell proliferation, and differentiation has been studied. In addition, the research has gradually expanded to the fields of glycolipid metabolism and energy balance. This article briefly reviews the role of TSK in the physiological and pathological process.

Introduction: Albeit that over 170 types of chemical modifications have been identified in RNAs, the biological functions of most of those decorations are still elusive. N7-methylguanosine (m7G), routinely occurring at the 5’ cap of mRNA or within tRNA and rRNA, also exists in internal mRNA. However, the “reader” proteins that recognize internal mRNA m7G and regulate the metabolism and fate of target mRNAs have yet to be identified. Here, we aim to identify the reader(s) of internal mRNA m7G and elucidate the biological function. Methods: To identify internal m7G reader(s), we utilized RNA-pull down, mass spectrometry (MS), RNA immunoprecipitation (RIP)-seq, and m7G-seq. To evaluate the interaction between QKI and G3BP1, we used Co-IP, immunofluorescence (IF) and proximity ligation assay (PLA). To investigate the function of QKI in stress granule (SG), we performed polyA & m7G RNA fluorescence in situ hybridization (FISH), triple quadrupole MS (QQQ-MS), and Ribo-seq. To assess the role of QKI in drug resistance, we carried out both in vitro cell survival assays and in vivo xenograft mouse model. Results: Our QQQ-MS results suggest cytoplasmic mRNA, in contrast to nuclei mRNA, are highly enriched with internal m7G modification. Quaking proteins (QKI), especially QKI7, can selectively recognize the internal mRNA m7G decoration in the cytosol of various cell types. Our high-throughput sequence data revealed over 1000 confident m7G-modified and QKI-binding RNA targets with a conserved motif, “GANGAN (N=A/U/G)”. Those transcripts are functionally enriched in the “pathways in cancer” and “Hippo signaling pathway”. More strikingly, internal m7G reader QKI7 directly interacts with the SG core protein G3BP1 and can shuttle a subset of m7G-modified transcripts into SG mRNA pool under oxidative stress condition. Additionally, we identified 314 confident m7G-modified & QKI7-binding & SG-enriched target genes in U2OS cells. Ribo-seq indicated that QKI7 modulates the translation efficiency of a set of m7G-modified transcripts via sequestering and silencing them in SGs. Moreover, in line with the observation that many chemotherapy drugs could trigger the assembly of SGs, QKI7 increases the sensitivity of cancer cells to drug treatment (e.g., doxorubicin) in vitro and in vivo in a m7G-dependent manner. Consistently, by analyzing the hepatocellular carcinoma (HCC) pharmacogenomic landscape study dataset, we found that HCC cell lines with higher QKI expression levels are more sensitive to a variety of chemotherapy or targeted therapeutic drugs. Conclusion: Our study identifies QKI as the first internal mRNA m7G reader, provides insights into the biological function of internal mRNA m7G modification in remodeling stress granules transcriptome, and highlights the therapeutic potential of targeting the QKI7/m7G axis in overcoming drug resistance. Citation Format: Zhicong Zhao, Lei Dong, Li Han, Yangchan Li, Jianhuang Xue, Keren Zhou, Wei Li, Xiaolan Deng, Ying Qing, Brandon Tan, Zhenhua Chen, Chao Shen, Andrew Small, Kitty Wang, Keith Leung, Zheng Zhang, Xi Qin, Qiang Xia, Rui Su, Jianjun Chen. Recognition of internal mRNA N7-methylguanosine by QKI shuttles transcripts into stress granules and modulates drug resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5685.

Background: As the most prevalent internal decorations in mammalian mRNA, N6-methyladenosine (m6A) has been reported to be involved in many physiological and pathological processes, including acute myeloid leukemia (AML). METTL3 and METTL14, the well-recognized m6A methyltransferase complex, contribute to AML. METTL16 is a recently identified m6A methyltransferase that has been reported to deposit m6A in a few targets. While, unlike METTL3/14, the biological functions of METTL16 are largely unknown. Here, we explored the function and mechanism of METTL16 in AML pathogenesis and evaluated its therapeutic potential for AML treatment. Methods: We performed CRISPR-Cas9 screen to evaluate the dependency of METTL16 in AML cells. We created METTL16 knockout (KO) cells and conditional KO mice to evaluate its role in leukemogenesis and normal hematopoiesis. We employed bone marrow transplantation (BMT), xenograft, and AML patient-derived xenograft (PDX) models to determine its role in AML development and progression. To identify the targets of METTL16, we performed m6A-seq and RNA-seq, followed m6A-qPCR, CLIP-qPCR, in vitro methyltransferase assays and RNA stability assays. To examine the effect of METTL16 on branched chain amino acid (BCAA) metabolism, we performed metabolic profiling with 13C, 15N-leucine. Results: CRISPR-Cas9 screen showed METTL16 is one of the most essential genes for the survival of AMLs. The AML cells display more robust dependency on METTL16 than METTL3/14. We found METTL16 is highly expressed in AML patients compared to healthy controls. METTL16 KO significantly inhibited AML cell proliferation, promoted cell apoptosis and myeloid differentiation in vitro, which could be totally reversed by forced expression of wild-type METTL16, but not catalytic-dead mutant. METTL16 depletion dramatically inhibited AML progression and prolonged survival of recipient mice in the BMT, xenograft and PDX models. In addition, METTL16 is highly expressed in LSCs contrast to leukemic bulk cells and METTL16 KO significantly attenuates LSC self-renewal in vitro and in vivo. By contrast, the role of METLL16 is largely spared in normal hematopoietic cells. Via integrated analysis of m6A-seq data and RNA-seq data, we identified two bona fide targets of METTL16, BCAT1 and BCAT2, which encode two critical BCAA transaminases in BCAA biosynthesis pathway. METTL16 promotes the expression of BCAT1 and BCAT2 via an m6A dependent manner. Metabolomics with 13C, 15N-leucine tracing showed that METTL16 KO results in suppressed pools of TCA cycle intermediates, some non-essential amino acids and nucleotides. Conclusion: We uncover a tumor-promoting role of METTL16 in AML and LSC self-renewal via reprogramming BCAA metabolism, in which METTL16 functions as an m6A methyltransferase to regulate expression of BCAT1 and BCAT2. Our data suggest that METTL16 is an attractive target for AML therapy. Citation Format: Li Han, Lei Dong, Keith Leung, Zhicong Zhao, Yangchan Li, Ying Qing, Jianhuang Xue, Chao Shen, Zhenhua Chen, Lei Gao, Kitty Wang, Keren Zhou, Wei Li, Brandon Tan, Zheng Zhang, Xi Qin, Rui Su, Xiaolan Deng, Jianjun Chen. METTL16 drives leukemogenesis and maintains leukemia stem cell self-renewal via reprogramming BCAA metabolism [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3617.

Metastatic triple negative breast cancer (TNBC) patients have a 5-year survival rate of just 12%. Therefore, there is an urgent need to discover novel molecular mechanisms that contribute to TNBC metastasis such as N6-methyladenosine (m6A) RNA modification. To do this, we conducted a selective CRISPR-cas9 screen of 14 m6A-regulators and identified an m6A reader protein, YTHDC1, as an essential gene for the survival of MDA-MB-231 cells. The Cancer Genome Atlas (TCGA) dataset showed that patients with poorer prognosis had elevated YTHDC1 expression, which supports a tumor-promoting role of YTHDC1. In vitro, genetic depletion of YTHDC1 significantly impaired Transwell migration and invasion of human TNBC (MDA-MB-231 and SUM159) cells. In vivo, YTHDC1 overexpressing TNBC cells engrafted into the mammary fat pad of NSG mice formed greater numbers and larger sizes of lung metastatic nodules compared to control. Conversely, YTHDC1 knockout (KO) cells produced fewer and smaller lung metastatic nodules compared to control. Together, our in vitro and in vivo data demonstrate YTHDC1’s role in promoting TNBC metastasis. To identify high confidence YTHDC1 targets, we conducted three layers of transcriptome-wide sequencing with MDA-MB-231 cells: RNA-seq (profiling differential gene expression and nuclear export), m6A-seq (profiling m6A methylation in mRNA), and RIP-seq (profiling YTHDC1 binding sites in mRNA). Pathway analysis of differentially expressed genes in MDA-MB-231 YTHDC1 KO cells identified pathways related to metastasis and TGF-β signaling, which is consistent with our phenotypic observations. Overlapping the three sequencing datasets identified SMAD3 as a YTHDC1 target mRNA. Mechanistically, YTHDC1 KO impairs the nuclear export of SMAD3 mRNA, resulting in reduced protein levels of this critical effector of TGF-β signaling. YTHDC1 KO significantly reduced Transwell migration and invasion of TGF-β induced TNBC cells and the expression of TGF-β responsive genes such as SNAIL, IL11, FN, and CTGF. Overexpression of SMAD3 was able to rescue the impaired migration and invasion of YTHDC1 KO TNBC cells and restore the expression of TGF-β responsive genes following TGF-β treatment. We also demonstrated that the oncogenic role of YTHDC1 is mediated through its recognition of m6A, as m6A-binding defective mutants of YTHDC1 were unable to rescue impaired Transwell migration and invasion of YTHDC1 KO TNBC cells. In summary, our study reveals that TNBC metastasis is mediated at least in part through YTHDC1’s function in promoting SMAD3 expression to augment the TGF-β signaling cascade. Citation Format: Brandon Tan, Wei Liu, Keren Zhou, Emily Prince, Lu Yang, Yangchan Li, Ying Qing, Li Han, Zhicong Zhao, Rui Su, Chun-Wei Chen, Jianjun Chen. The N6-methyladenosine reader YTHDC1 is essential for TGF-beta-mediated metastasis of triple negative breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2188.

Background This study was conducted in patients with type 2 diabetes mellitus (T2DM) to assess the association between visceral fat area (VFA) and cardiac hemodynamics. Methods A total of 568 patients with type 2 diabetes (mean age 54±12 years; 40.8% of women) were enrolled. Visceral fat area (VFA, m2) and subcutaneous fat area (SFA, m2) were evaluated by a bioelectrical impedance analyzer. Cardiac hemodynamics were measured by echocardiography, and other clinical and laboratory variables were also assessed and recorded. Patients were divided into those with VFA ≤ 100 (n=369) and those with VFA > 100 (n=199). Results VFA, SFA, LVMI (left ventricular mass index), left atrial diameter, left ventricular diastolic diameter (LvDd), interventricular septal thickness (IVST), left ventricular systolic diameter (LvSd), and posterior wall thickness (PWT) levels in high-V groups were significantly higher than those in low-V groups. Correlation analysis showed that VFA was positively correlated with LVMI (r=0.120, p=0.004), LVM (r=0.249, p

Summary Fat mass and obesity-associated protein (FTO), an RNA N6-methyladenosine (m6A) demethylase, plays oncogenic roles in various cancers, presenting an opportunity for the development of effective targeted therapeutics. Here, we report two potent small-molecule FTO inhibitors that exhibit strong anti-tumor effects in multiple types of cancers. We show that genetic depletion and pharmacological inhibition of FTO dramatically attenuate leukemia stem/initiating cell self-renewal and reprogram immune response by suppressing expression of immune checkpoint genes, especially LILRB4. FTO inhibition sensitizes leukemia cells to T cell cytotoxicity and overcomes hypomethylating agent-induced immune evasion. Our study demonstrates that FTO plays critical roles in cancer stem cell self-renewal and immune evasion and highlights the broad potential of targeting FTO for cancer therapy.