Screening and Identifying m6A Regulators as an Independent Prognostic Biomarker in Pancreatic Cancer Based on The Cancer Genome Atlas Database.

BACKGROUND: Pancreatic cancer is one of the most malignant tumors of the digestive system, and its treatment has rarely progressed for the last two decades. Studies on m6A regulators for the past few years have seemingly provided a novel approach for malignant tumor therapy. m6A-related factors may be potential biomarkers and therapeutic targets. This research is focused on the gene characteristics and clinical values of m6A regulators in predicting prognosis in pancreatic cancer. METHODS: In our study, we obtained gene expression profiles with copy number variation (CNV) data and clinical characteristic data of 186 patients with pancreatic cancer from The Cancer Genome Atlas (TCGA) portal. Then, we determined the alteration of m6a regulators and their correlation with clinicopathological features using the log-rank tests, Cox regression model, and chi-square test. Additionally, we validated the prognostic value of m6A regulators in the International Cancer Genome Consortium (ICGC). RESULTS: The results suggested that pancreatic cancer patients with ALKBH5 CNV were associated with worse overall survival and disease-free survival than those with diploid genes. Additionally, upregulation of the writer gene ALKBH5 had a positive correlation with the activation of AKT pathways in the TCGA database. CONCLUSION: Our study not only demonstrated genetic characteristic changes of m6A-related genes in pancreatic cancer and found a strong relationship between the changes of ALKBH5 and poor prognosis but also provided a novel therapeutic target for pancreatic cancer therapy.

LincRNA-EPS alleviates severe acute pancreatitis by suppressing HMGB1-triggered inflammation in pancreatic macrophages.

Acute pancreatitis (AP), an inflammatory disorder of the pancreas with a high hospitalization rate, frequently leads to systemic inflammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS). However, therapeutic targets for effective treatment and early intervention of AP are still urgently required to be identified. Here, we have observed that the expression of pancreatic lincRNA-EPS, a long intergenic non-coding RNA, is dynamically changed during both caerulein-induced AP (Cer-AP) and sodium taurocholate-induced severe AP (NaTc-SAP). The expression pattern of lincRNA-EPS is negatively correlated with the typical inflammatory genes such as IL-6, IL-1ß, CXCL1, and CXCL2. Further studies indicate that knockout of lincRNA-EPS aggravates the pathological symptoms of AP including more induction of serum amylase and lipase, severe edema, inflammatory cells infiltration and acinar necrosis in both experimental AP mouse models. Besides these intrapancreatic effects, lincRNA-EPS also protects against tissue damages in the extra-pancreatic organs such as lung, liver, and gut in the NaTc-SAP mouse model. In addition, we have observed more serum pro-inflammatory cytokines TNF-α and IL-6 in the lincRNA-EPS-/- NaTc-SAP mice and more extracellular HMGB1 around injured acinar cells in the pancreas from lincRNA-EPS-/- NaTc-SAP mice, compared with their respective controls. Pharmacological inhibition of NF- κ B activity by BAY11-7082 significantly abolishes the suppressive effect of lincRNA-EPS on TLR4 ligand-induced inflammatory genes in macrophages. Our study has described a protective role of lincRNA-EPS in alleviating AP and SAP, outlined a novel pathway that lincRNA-EPS suppresses HMGB1-NF- κ B-dependent inflammatory response in pancreatic macrophages and provided a potential therapeutic target for SAP.

Discoveries in Pancreatic Physiology and Disease Biology Using Single-Cell RNA Sequencing.

Transcriptome analysis is used to study gene expression in human tissues. It can promote the discovery of new therapeutic targets for related diseases by characterizing the endocrine function of pancreatic physiology and pathology, as well as the gene expression of pancreatic tumors. Compared to whole-tissue RNA sequencing, single-cell RNA sequencing (scRNA-seq) can detect transcriptional activity within a single cell. The scRNA-seq had an invaluable contribution to discovering previously unknown cell subtypes in normal and diseased pancreases, studying the functional role of rare islet cells, and studying various types of cells in diabetes as well as cancer. Here, we review the recent in vitro and in vivo advances in understanding the pancreatic physiology and pathology associated with single-cell sequencing technology, which may provide new insights into treatment strategy optimization for diabetes and pancreatic cancer.

Brusatol Enhances the Chemotherapy Efficacy of Gemcitabine in Pancreatic Cancer via the Nrf2 Signalling Pathway.

Although gemcitabine is the standard chemotherapy treatment for advanced pancreatic cancer, its benefits are quite limited due to prevalent chemoresistance, and the mechanism underlying gemcitabine chemoresistance remains unclear. Currently, Nrf2 has been deemed as a significant contributor to gemcitabine chemoresistance in pancreatic cancer. Brusatol is a unique inhibitor of the Nrf2 pathway, and in previous studies, we determined that brusatol exhibits the effects of growth inhibition and proapoptosis in pancreatic cancer cells. Due to these data, we speculate that brusatol can reverse gemcitabine-induced Nrf2 activation and propose that it can enhance gemcitabine efficacy in treating pancreatic cancer. In this study, we first proved that brusatol can effectively inhibit the Nrf2 signalling pathway and increase ROS accumulation in pancreatic cancer cells. Next, we demonstrated that brusatol can abrogate gemcitabine-induced Nrf2 activation in pancreatic cancer cells. In addition, we discovered that brusatol potentiates gemcitabine-induced growth inhibition and apoptosis in human pancreatic cancer cells. In nude mice with PANC-1 xenografts, treatment with a combination of brusatol and gemcitabine considerably reduced in vivo tumour growth compared with control treatment or treatment with either brusatol or gemcitabine alone. Immunohistochemical staining also showed that Nrf2 expression levels were reduced in brusatol-treated xenograft tumour tissues. In summary, our results suggest that brusatol is capable of enhancing the antitumour effects of gemcitabine in both pancreatic cancer cells and PANC-1 xenografts via suppressing the Nrf2 pathway.

Complete genomic sequence of a novel macluravirus, alpinia oxyphylla mosaic virus (AloMV), identified in Alpinia oxyphylla.

A macluravirus, tentatively named alpinia oxyphylla mosaic virus (AloMV), was identified in Alpinia oxyphylla, and its complete genomic sequence determined. The positively single-stranded RNA genome is comprised of 8213 nucleotides excluding the poly (A) tail, and contains one large open reading frame encoding a polyprotein of 2,626 amino acids. Blastp search showed that the polyprotein of AloMV shared 48%~68% aa sequence identities with other reported macluraviruses. Phylogenetic analysis based on the nucleotide sequence of the polyprotein showed that AloMV, together with all other macluraviruses, clustered into the same group most closely related to cardamom mosaic virus, sharing 66.3% nt and 68% aa sequence identities, respectively. These data above suggest that AloMV represents an isolate of a putative new member within the genus Macluravirus.

Dermokine contributes to epithelial-mesenchymal transition through increased activation of signal transducer and activator of transcription 3 in pancreatic cancer.

Dermokine (DMKN) was first identified in relation to skin lesion healing and skin carcinoma. Recently, its expression was associated with pancreatic cancer tumorigenesis, although its involvement remains poorly understood. Herein, we showed that DMKN loss of function in Patu-8988 and PANC-1 pancreatic cancer cell lines resulted in reduced phosphorylation of signal transducer and activator of transcription 3, and increased activation of ERK1/2 and AKT serine/threonine kinase. This decreased the proliferation ability of pancreatic ductal adenocarcinoma (PDAC) cells. In addition, DMKN knockdown decreased the invasion and migration of PDAC cells, partially reversed the epithelial-mesenchymal transition, retarded tumor growth in a xenograft animal model by decreasing the density of microvessels, and attenuated the distant metastasis of human PDAC in a mouse model. Taken together, these data suggested that DMKN could be a potential prognostic biomarker and therapeutic target in pancreatic cancer.

Brusatol inhibits growth and induces apoptosis in pancreatic cancer cells via JNK/p38 MAPK/NF-κb/Stat3/Bcl-2 signaling pathway.

Brusatol, isolated from brucea, has been proved to exhibit anticancer influence on various kind of human malignancies. However, the role that brusatol plays in pancreatic cancer is seldom known by the public. Through researches brusatol was proved to inhibit growth and induce apoptosis in both PATU-8988 and PANC-1 cells by decreasing the expression level of Bcl-2 and increasing the expression levels of Bax, Cleaved Caspase-3. Then we found the activation of the JNK, p38 MAPK and inactivation of the NF-κb, Stat3 are related with the potential pro-apoptotic signaling pathways. However, SP600125 could not only abrogated the JNK activation caused by brusatol, but also reverse the p38 activation and the decrease of Bcl-2 as SB203580 did. Besides, SP600125 and SB203580 also reversed the inactivation of NF-κb and Stat3. Furthermore, BAY 11-7082 and S3I-201 indeed had the similar effect as brusatol had on the expression of Phospho-Stat3 and Bcl-2. To sum up, we came to a conclusion that in pancreatic cancer, brusatol do inhibit growth and induce apoptosis. And we inferred that brusatol illustrates anticancer attribution via JNK/p38 MAPK/NF-κb/Stat3/Bcl-2 signaling pathway.

Isoorientin induces apoptosis, decreases invasiveness, and downregulates VEGF secretion by activating AMPK signaling in pancreatic cancer cells.

Isoorientin (or homoorientin) is a flavone, which is a chemical flavonoid-like compound, and a 6-C-glucoside of luteolin. Isoorientin has been demonstrated to have anti-cancer activities against various tumors, but its effects on pancreatic cancer (PC) have not been studied in detail. In this study, we aim to investigate whether isoorientin has potential anti-PC effects and its underlying mechanism. In PC, isoorientin strongly inhibited the survival of the cells, induced cell apoptosis, and decreased its malignancy by reversing the expression of epithelial-mesenchymal transition and matrix metalloproteinase and decreased vascular endothelial growth factor expression. Meanwhile, we investigated the activity of the AMP-activated protein kinase (AMPK) signaling pathway after isoorientin treatment, which was forcefully activated by isoorientin, as expected. In addition, in the PC cells that were transfected with lentivirus to interfere with the expression of the gene PRKAA1, there were no differences in the apoptosis rate and the expression of malignancy biomarkers in the tumors of the isoorientin-treated and untreated groups. Thus, we demonstrated that isoorientin has potential antitumor effects via the AMPK signaling pathway, and isoorientin merits further investigation.

Wintertime haze deterioration in Beijing by industrial pollution deduced from trace metal fingerprints and enhanced health risk by heavy metals.

Airborne particulate matter (PM) was collected in Beijing between 24 February and 12 March 2014 to investigate chemical characteristics and potential industrial sources of aerosols along with health risk of haze events. Results showed secondary inorganic aerosol was the major contributor to PM2.5 during haze days. Utilizing specific elements, including Fe, La, Tl and As, as fingerprinting tracers, four emission sources, namely iron and steel manufacturing, petroleum refining, cement plant, and coal combustion were explicitly identified; their elevated contributions to PM during haze days were also estimated. The average cancer risk from exposure to inhalable PM toxic metals was 1.53 × 10(-4) on haze days, which is one order of magnitude higher than in other developed cities. These findings suggested heavy industries emit large amounts of not only primary PM but also precursor gas pollutants, leading to secondary aerosol formation and harm to human health during haze days.

α-Solanine inhibits vascular endothelial growth factor expression by down-regulating the ERK1/2-HIF-1α and STAT3 signaling pathways.

In tumors, vascular endothelial growth factor (VEGF) contributes to angiogenesis, vascular permeability, and tumorigenesis. In our previous study, we found that α-solanine, which is widespread in solanaceae, has a strong anti-cancer effect under normoxia. However, it is unknown whether α-solanine has a similar effect under hypoxia. We used cobalt chloride (CoCl2) to mimic hypoxia in vitro. HIF-1α, which is almost undetectable under normoxia, was significantly increased. Simultaneously, another regulator of VEGF, STAT3, was also significantly activated by CoCl2. We utilized α-solanine in co-culture with CoCl2. α-solanine decreased the expression of VEGF and loss of E-cadherin. α-solanine also suppressed the activation of phospho-ERK1/2 (p-ERK1/2), HIF-1α, and STAT3 signaling. The results provide new evidence that α-solanine has a strong anti-cancer effect via the ERK1/2-HIF-1α and STAT3 signaling pathways and suggest that it may be a potential new drug.