Imbalance of early-life vitamin D intake targets ROS-mediated crosstalk between mitochondrial dysfunction and differentiation potential of MSCs associated the later obesity.

BACKGROUND: Obesity is characterized by excessive fat accumulation, which is related with abnormal pluripotency of mesenchymal stem cells (MSCs). Recently, there is growing evidence that the disorder of maternal vitamin D (VD) intake is a well-known risk factor for long-term adverse health outcomes to their offspring. Otherwise, less is known of its repercussion and underlying mechanisms on the different differentiation potential of MSCs. METHODS: Four-week-old female C57BL/6J mice were fed with different VD reproductive diets throughout the whole pregnancy and lactation. The characteristics of BMSCs from their seven-day male offspring, VDR knockdown establishment of HuMSCs and HuMSCs under the different VD interventions in vitro were confirmed by flow cytometry, RT-PCR, and immunofluorescence. The roles of VD on their mitochondrial dysfunction and differentiation potential were also investigated. Then their remaining weaned male pups were induced by administrating high-fat-diet (HFD) for 16 weeks and normal fat diet was simultaneously as controls. Their lipid accumulation and adipocytes hypertrophy were determined by histological staining and related gene expressions. RESULTS: Herein, it was proved that imbalance of early-life VD intake could significantly aggravate the occurrence of obesity by inducing the adipogenesis through affecting the VD metabolism and related metabolites (P < 0.05). Moreover, abnormally maternal VD intake might be involved on the disorders of differentiation potential to inhibit the maintenance of MSCs stemness through increasing the productions of ROS, which was accompanied by impairing the expression of related genes on the adipo-osteogenic differentiation (P < 0.05). Moreover, it was along with increasing potential of adipogenic differentiation of MSCs as higher ROS in the state of VD deficiency, while excessive maternal VD status could conversely enhance the osteogenic differentiation with slightly lower ROS (P < 0.05). Furthermore, the underlying mechanisms might be involved on the mitochondria dysfunctional, especially the mitophagy, by activating the LC3b, P62 and etc. using in vivo and in vitro studies (P < 0.05). CONCLUSION: These findings demonstrated that imbalance of early-life VD intake could target ROS-mediated crosstalk between mitochondrial dysfunction and differentiation potential of MSCs, which was significantly associated with the later obesity. Obviously, our results could open up an attractive modality for the benefits of suitable VD intake during the pregnancy and lactation.

Dynamic regulation of KIF15 phosphorylation and acetylation promotes focal adhesions disassembly in pancreatic cancer.

Pancreatic cancer (PC) is prone to distant metastasis in the early stage, which is attributed to the strong migration ability of tumor cells. Focal adhesion turnover is essential for cancer cell metastasis, and the integrin recycling process is a key activation pathway for focal adhesion depolymerization. To identify the key motor protein involving in the integrin ß1 recycling, we screened kinesin proteins involved in integrin ß1 recycling using a kinesin family siRNA library and identified kinesin family 15 (KIF15) as a key regulator. KIF15 was upregulated in metastasis PC tissues and promoted PC cell migration and invasion. We identified KIF15 as a key component mediating integrin ß1/FAK signaling that accelerated FA disassembly in a FAK-Y397-dependent manner. KIF15 recruited PI3K-C2α to promote integrin ß1/FAK signaling and FA disassembly in a RAB11A-dependent manner. The C-terminal tail of KIF15 is required for the PI3K-C2α interaction and RAB11A activation. In addition, we also found that SIRT1-mediated acetylation of KIF15 is essential for KIF15 phosphorylation, which is the key activation event in motor protein function. Together, these findings indicate that KIF15 interacts with PI3K-C2α to promote FA turnover in PC cells by controlling the endosome recycling of integrin ß1 in a SIRT1 acetylation modification-dependent manner, eventually promoting focal adhesions turnover and distant metastasis in PC.

LINC00941 promotes pancreatic cancer malignancy by interacting with ANXA2 and suppressing NEDD4L-mediated degradation of ANXA2.

Recently, long non-coding RNAs (lncRNA) have been proven to regulate pancreatic cancer (PC) progression. We aimed to explore the pathogenesis of LINC00941 in PC regarding protein binding. By using PCR analysis, we found that LINC00941 was overexpressed in PC tissues and was higher in patients with liver metastasis than in patients without liver metastasis. In addition, high LINC00941 expression was associated with a poor prognosis. Functional experiments and mice models were respectively used to evaluate PC cell proliferation and migration in vitro and in vivo. The results suggested that LINC00941 overexpression promoted PC proliferation and metastasis. Subsequently, RNA pull-down, mass spectrometry (MS), and RNA-binding protein immunoprecipitation (RIP) were performed to identify LINC00941-interacting proteins. The results suggested that ANXA2 was the potential LINC00941-interacting protein. Nucleotides 500-1390 of LINC00941 could bind to the Annexin 1 domain of ANXA2. LINC00941-mediated malignant phenotype of PC was reversed by ANXA2 depletion. Co-immunoprecipitation (Co-IP) followed by MS was conducted to determine the potential interacting protein of LINC00941. The results illustrated that NEDD4L, an E3 ligase involved in ubiquitin-mediated protein degradation, bound to the Annexin 1 domain of ANXA2 and promoted its degradation. Mechanically, LINC00941 functioned as a decoy to bind to ANXA2 and suppressed its degradation by enclosing the domain that binds to NEDD4L. Eventually, LINC00941 upregulated ANXA2 and activated FAK/AKT signaling, increasing PC cell proliferation and metastasis. This study indicates that LINC00941 promotes PC proliferation and metastasis by binding ANXA2 and potentiating its stability, leading to the activation of FAK/AKT signaling. Our data demonstrate that LINC00941 may serve as a novel target for prognosis and therapy.

Exosome-derived FGD5-AS1 promotes tumor-associated macrophage M2 polarization-mediated pancreatic cancer cell proliferation and metastasis.

Inflammatory molecules and exosomes are crucial for signal transduction between tumor-associated macrophages and tumor cells. IL-6, a key inflammatory molecule secreted by M2 macrophages after polarization, can mediate malignant progression of pancreatic cancer (PC). However, the functions and mechanisms of IL-6 and tumor-derived exosomes in tumor-associated macrophages and PC remain unclear. Transcriptome chip and quantitative reverse transcription PCR experiments indicated that FGD5-AS1 induced IL-6 and high FGD5-AS1 expression correlated with the poor prognosis in PC patients. RNA pulldown, mass spectrometry, and dual luciferase reporter assays were used to identify the mechanism of exosomal FGD5-AS1 in promoting PC progression and M2 macrophage polarization. FGD5-AS1 exerted cancer-promoting functions when co-cultured with M2 macrophages. PC-derived exosomal FGD5-AS1 stimulated M2 macrophage polarization by activating STAT3/NF-κB pathway. FGD5-AS1 interacts with p300, resulting in STAT3 acetylation, thus promoting nuclear localization and transcriptional activity of STAT3/NF-κB. These data indicated that PC cells generate FGD5-AS1-rich exosomes, which cause M2 macrophage polarization to promote the malignant behaviors of PC cells. Targeting exosomal FGD5-AS1 may provide a potential diagnosis and treatment strategy for PC.

CircRNF13 Promotes the Malignant Progression of Pancreatic Cancer through Targeting miR-139-5p/IGF1R Axis.

BACKGROUND: Mounting evidence has shown circular RNAs (circRNAs) play an important role in the initiation and progression of pancreatic cancer (PC). Meanwhile, circRNAs may serve as the biomarkers for the diagnosis, treatment, and prognosis of PC. Therefore, it is urgent to elucidate the function and underlying mechanism of circRNAs in the development of PC. METHODS: The Cancer-Specific CircRNA Database (CSCD), Circular RNA Interactome database (circinteractome database), and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to verify the expression level of circRNF13 in PC cell lines. Fluorescence in situ hybridization (FISH) and RNase protection assay were used to detect the localization and structure of circRNF13. Then, cell functional experiments were employed to estimate the proliferated, migrated, and invasive abilities in PC. Furthermore, bioinformatic tools, luciferase dual reporter assay, and RT-qPCR were used to investigate the interaction among circRNF13, miR-139-5p, and IGF1R. Eventually, the rescue functional experiments were employed to confirm that circRNF13 targeted the miR-139-5p/IGF1R axis to participate in the development of PC. RESULTS: CircRNF13 was overexpressed in PC cell lines compared with the normal pancreatic duct cell line. Additionally, inhibition of circRNF13 impaired the proliferation, migration, and invasion of PC cells. CircRNF13 could serve as the molecular sponge of miR-139-5p to inhibit its association with IGF1R that eventually accelerated the malignant progression of PC. CONCLUSION: CircRNF13 serves as a competitive endogenous RNA of IGF1R to inhibit the function of miR-139-5p that eventually reinforces the malignant phenotype of PC.

Hypoxia-Induced ZWINT Mediates Pancreatic Cancer Proliferation by Interacting With p53/p21.

p53/p21 signaling plays a vital role in pancreatic cancer (PC) progression. ZWINT was shown to function as an oncoprotein in the progression of multiple cancers. However, the involvement of ZWINT and p53 activation in the progression of PC remains poorly understood. Bioinformatics and tissue array chip analyses were performed to evaluate ZWINT expression in pancreatic cancer. ZWINT mRNA and protein expression were evaluated in normoxia and hypoxia. CHIP was used to evaluate HIF1α interaction with the ZWINT promoter. CCK8, colony formation, EDU, and cell cycle analysis were used to examine PC cell proliferation. Immunoprecipitation and immunofluorescence were used to examine the interaction of ZWINT, MDM2, and p53. p53 activity was evaluated by q-PCR and luciferase assay. Protein degradation and ubiquitination assays were used to analyze the role of ZWINT in p53 ubiquitination. ZWINT was overexpressed in pancreatic cancer and induced in hypoxia. ZWINT promoted pancreatic cancer growth and cell cycle progression. Bioinformatic analysis revealed that ZWINT may regulate the p53 signal pathway. ZWINT interacts with p53 and promotes its ubiquitination and degradation. ZWINT promoted proliferation via p53/p21. Immunohistochemistry of clinical specimens revealed that that ZWINT expression was significantly negatively correlated with p53/p21. Our data showed that hypoxia regulates the expression of ZWINT, which activated p53/p21 signaling pathway to promote PC growth.

CircSEC24A upregulates TGFBR2 expression to accelerate pancreatic cancer proliferation and migration via sponging to miR-606.

BACKGROUND: Circular RNA (circRNA), producing by special selective splicing, was widely expressed in the cytoplasm of eukaryotic cells as a newly non-coding RNAs. It played different roles in a variety of diseases including cancer and performed different functions. Nonetheless, reports on the specific function of circRNA in pancreatic cancer (PC) were still rarely so far. In particular, the role of circSEC24A in PC remains unclear. METHODS: Real-time fluorescent quantitative PCR was used to evaluate the expression level of circSEC24A in pancreatic cancer tissues and cell lines. Furthermore, we used some functional experiments, such as EDU and Transwell assays, to explore the effects of circSEC24A on the proliferation and invasiveness of pancreatic cancer. Finally, the corresponding relationship among circSEC24A, miR-606 and TGFBR2 was explored by dual luciferase reporter and other mechanism studies. RESULTS: The expression of circSEC24A in both pancreatic cancer tissues and cell lines was evidently up-regulated. Furthermore, knockdown of circSEC24A significantly inhibited the proliferative, migration and invasive capacity of pancreatic cancer cells, whereas miR-606 inhibitor obviously counteracted these effects. Further study confirmed that circSEC24A alleviated suppression on target TGFBR2 expression by directly sponging miR-606 and then influenced the tumorigenesis of pancreatic cancer. CONCLUSIONS: These findings indicated that the progression of pancreatic cancer can be driven by circSEC24A influencing miR-606/TGFBR2 axis. Therefore, circSEC24A might be used as a critical biomarker influencing the early diagnosis and prognosis of pancreatic cancer.

Circular RNA hsa_circ_0006117 Facilitates Pancreatic Cancer Progression by Regulating the miR-96-5p/KRAS/MAPK Signaling Pathway.

Circular RNAs (circRNAs) play key roles in many malignant tumors, including pancreatic cancer (PC); however, whether circular RNA hsa_circ_0006117, a newly identified circRNA, has a role in PC has not been investigated. Here, in order to elucidate the role and potential molecular mechanisms of circRNAs, we utilized bioinformatic tolls to screen the differentially expressed circRNAs in PC. Subsequently, circular RNA hsa_circ_0006117 was identified as being highly expressed in PC tissues in a screen of two GEO datasets, which was further verified in PC cell lines and tissues. Then, its molecular characteristics were investigated using methods such as Sanger sequencing and fluorescence in situ hybridization (FISH). Functional experiments subsequently indicated that circular RNA hsa_circ_0006117 facilitated the malignant behaviors of PC cells, prompting that it plays an oncogenic role in PC. Moreover, we found that circular RNA hsa_circ_0006117 exerts its PC-promoting effects via activating the KRAS/mitogen-activated protein kinase (MAPK) signaling pathway. Through bioinformatics exploration and dual-luciferase reporter assays, miR-96-5p was identified as a downstream target of circular RNA hsa_circ_0006117. A series of assays confirmed that circular RNA hsa_circ_0006117 acted as a miR-96-5p sponge, thereby promoting the malignant features of PC in a miR-96-5p/KRAS axis-dependent manner. Taken together, our study indicated, for the first time, that the specifically highly expressed circular RNA hsa_circ_0006117 facilitates PC progression via the modulation of the miR-96-5p/KRAS/MAPK signaling pathway and might be a hopeful therapeutic target for PC.

[6]-Paradol suppresses proliferation and metastases of pancreatic cancer by decreasing EGFR and inactivating PI3K/AKT signaling.

BACKGROUND: The underlying mechanism behind the tumorigenesis and progression of pancreatic cancer is not clear, and treatment failure is generally caused by early metastasis, recurrence, drug resistance and vascular invasion. Exploring novel therapeutic regimens is necessary to overcome drug resistance and improve patients outcomes. METHODS: Functional assays were performed to investigate the role of [6]-Paradol (6-P) in proliferation and metastasis of pancreatic cancer in vitro and in vivo. The interaction between EGFR and 6-P was tested by KEGG enrichment analysis and molecular docking analysis. qRT-PCR was performed to detect the mRNA expression of EGFR in 6-P treated groups. Involvement of the PI3K/AKT pathway was measured by western blotting. RESULTS: 6-P significantly suppressed pancreatic cancer cell proliferation and metastasis. KEGG enrichment analysis and molecular docking analysis suggested that there existed certain interaction between EGFR and 6-P. In addition, 6-P obviously decreased EGFR protein expression level but did not change the mRNA expression level of EGFR. 6-P could induce degradation of EGFR through decreasing the protein stability of EGFR and enhancing the ubiquitin-mediated proteasome-dependent degradation, 6-P-mediated EGFR degradation led to inactivation of PI3K/AKT signaling pathway. However, ectopic expression of EGFR protein resulted in resistance to 6-P-mediated inactivity of PI3K/AKT signaling and inhibition of malignant phenotype of pancreatic cancer. Inversely, erlotinib could enhance the 6-P-mediated anticancer activity. CONCLUSION: Our data indicated that 6-P/EGFR/PI3K/AKT signaling axis might become one of the potential therapies for the treatment of pancreatic cancer.

LncRNA CERS6-AS1 promotes proliferation and metastasis through the upregulation of YWHAG and activation of ERK signaling in pancreatic cancer.

LncRNAs play essential regulatory roles in pancreatic cancer (PC) tumorigenesis and progression. We aimed to investigate the role of lncRNA CERS6-AS1 in PC. CERS6-AS1 expression was determined in PC tissues and cell lines by PCR analysis. The roles of CERS6-AS1 on proliferation, migration, invasion, and epithelial to mesenchymal transition (EMT) were confirmed via CCK-8 assay, EDU assay, transwell assay, wound healing assay, and western blot assay. Besides, the interaction between CERS6-AS1 and their target genes was verified by luciferase report assays and RIP assays. Animal assays and clinical data analysis were performed to validate the functions in vivo. We found that lncRNA CERS6-AS1 was highly expressed in PC tissues and cells. Additionally, high expression of CERS6-AS1 was obviously associated with poor prognosis. Functional assays demonstrated that CERS6-AS1 downregulation significantly inhibited PC cell growth and migration. Moreover, CERS6-AS1 exerted as a molecular sponge for miR-217-5p (miR-217), and miR-217 was confirmed as a potential target of CERS6-AS1. Subsequently, miR-217 suppressed PC cell proliferation and metastasis by directly targeting YWHAG, which interacted with RAF1 and promoted its phosphorylation, leading to RAF1-mediated ERK signaling activation and translocation of phosphorylated ERK from the cytoplasm to the nucleus. Mechanically, CERS6-AS1 silencing significantly inhibited PC cell proliferation and metastasis via a miR-217/YWHAG/RAF1 signaling axis. CERS6-AS1 exerts as a carcinogen in PC to promote malignant features and behaves as a competitive endogenous RNA for miR-217. We identified CERS6-AS1 as a potential biomarker or therapeutic target to improve PC diagnosis and treatment outcomes.