ZNF263 cooperates with ZNF31 to promote the drug resistance and EMT of pancreatic cancer through transactivating RNF126.

The poor prognosis of pancreatic ductal adenocarcinoma (PDAC) is attribute to the aggressive local invasion, distant metastasis and drug resistance of PDAC patients, which was strongly accelerated by epithelial-mesenchymal transition (EMT). In current study, we systematically investigate the role of ZNF263/RNF126 axis in the initiation of EMT in PDAC in vitro and vivo. ZNF263 is firstly identified as a novel transactivation factor of RNF126. Both ZNF263 and RNF126 were overexpressed in PDAC tissues, which were associated with multiple advanced clinical stages and poor prognosis of PDAC patients. ZNF263 overexpression promoted cell proliferation, drug resistance and EMT in vitro via activating RNF126 following by the upregulation of Cyclin D1, N-cad, and MMP9, and the downregulation of E-cad, p21, and p27. ZNF263 silencing contributed to the opposite phenotype. Mechanistically, ZNF263 transactivated RNF126 via binding to its promoter. Further investigations revealed that ZNF263 interacted with ZNF31 to coregulate the transcription of RNF126, which in turn promoted ubiquitination-mediated degradation of PTEN. The downregulation of PTEN activated AKT/Cyclin D1 and AKT/GSK-3ß/ß-catenin signaling, thereby promoting the malignant phenotype of PDAC. Finally, the coordination of ZNF263 and RNF126 promotes subcutaneous tumor size and distant liver metastasis in vivo. ZNF263, as an oncogene, promotes proliferation, drug resistance and EMT of PDAC through transactivating RNF126.

Cooperation of Musashi-2, Numb, MDM2, and P53 in drug resistance and malignant biology of pancreatic cancer.

Our earlier work showed that Musashi (MSI)-2 promoted the development of pancreatic cancer (PC) by down-regulating Numb, which prevented murine double-minute (MDM)-2-mediated p53 ubiquitin degradation. Thus, we investigate the relationship among MSI2, Numb, MDM2, and p53 in PC in vitro and invivo, an association that has not been reported to our knowledge. MSI2 had no relationship with mutant p53 (mtp53) and wild-type p53 (wtp53) in normal PC cells. However, in response to gemcitabine or cisplatin treatment, MSI2 silencing simultaneously down-regulated MDM2 and up-regulated Numb and wtp53 protein levels. Moreover, these 4 endogenous proteins can be coimmunoprecipitated as a quaternary complex. Numb small interfering RNA (siRNA) reversed the MSI2 silencing-induced p53 increase. During treatment with chemical agents, MSI2 silencing decreased drug resistance and cell motility in vitro and inhibited tumor growth in vivo, all of which were significantly reversed by p53 siRNA. MSI2 was also negatively associated with Numb and positively associated with MDM2 expression in tissue. Overexpression of MSI2, MDM2, and mtp53 and weak expression of Numb were closely associated with aggressive clinicopathologic characteristics and poor prognosis for patients with PC. MSI2 negatively regulates wtp53 protein by up-regulating MDM2 and down-regulating Numb after treatment with chemical agents. MSI2 promotes drug resistance and malignant biology of PC in a p53-dependent manner.-Sheng, W., Dong, M., Chen, C., Wang, Z., Li, Y., Wang, K., Li, Y., Zhou, J. Cooperation of Musashi-2, Numb, MDM2, and P53 in drug resistance and malignant biology of pancreatic cancer.

[Advance in research on the association of ALDH2 gene polymorphisms with cancer susceptibility in drinkers].

Aldehyde dehydrogenase 2 (ALDH2), as one of the most important alcohol metabolizing enzymes, plays a significant role in the detoxification process of acetaldehyde which is a main carcinogenic product of alcoholic metabolism. Alteration in its genotypes (particularly at the site of rs671) is closely associated with a variety of tumors in drinkers. Recent advance in the research of the association of the ALDH2 gene rs671 polymorphisms with cancer susceptibility in drinkers is reviewed.

Overexpression of calreticulin contributes to the development and progression of pancreatic cancer.

We studied the clinicopathological significance for Calreticulin (CRT) expression in pancreatic cancer (PC), and its functional relationship with other signaling genes (especially with p53) in regulating the biological behavior of PC cells. IHC, IF, IB, and real-time PCR were used to detect CRT expression in PC, while transfection and drug intervention were used to investigate the functional relationship of CRT with other signaling genes. IHC showed both CRT and p53 expression was significantly increased in PC, compared to that in paired non-cancerous pancreatic tissues (P < 0.001). High expression of CRT was positively associated with tumor UICC stage and lymph nodes metastasis (P = 0.034 and P = 0.015), and was an independent adverse prognostic indicator in patients with PC. No relationship was found between CRT and p53 expression in spearman's rank correlation test. Altered expression of CRT did not change p53, MDM2, pho-AKT, pho-p38, and pho-JNK expression, but had a specific regulation on pho-ERK. Meanwhile, CRT-regulated cell proliferation, migration, and invasion of PC cells in MEK/ERK pathway dependent manner. In addition, CRT knockdown significantly decreased pho-ERK expression and cell chemoresistance independent of activated p53 and caspase-3-related apoptosis in gemcitabine- or oxaliplatin-treated Capan-2 cells. Our study first demonstrated that overexpression of CRT contributed to the development and progression of PC through MEK/ERK-signaling pathway but independent of p53. The interaction between CRT and MEK/ERK pathway might provide a new idea for revealing malignant biology and supplying new gene targeted chemotherapy of PC.

Correction: Musashi2 promotes the development and progression of pancreatic cancer by down-regulating Numb protein.

[This corrects the article DOI: 10.18632/oncotarget.8736.].

GINS2 promotes EMT in pancreatic cancer via specifically stimulating ERK/MAPK signaling.

Go-Ichi-Ni-San 2 (GINS2), as a newly discovered oncogene, is overexpressed in several cancers. However, the specific role of GINS2 in the development of pancreatic cancer (PC), to our knowledge, is poorly understood. We systematically explored the potential role of GINS2 in epithelial-mesenchymal-transition (EMT)-stimulated PC in vitro and vivo. GINS2 was overexpressed in human PC specimens, which was positively associated with tumor size (P = 0.010), T stage (P = 0.006), vascular invasion (P = 0.037), and the poor prognosis (P = 0.004). Interestingly, a close correlation between GINS2, E-cadherin, and Vimentin (P = 0.014) was found in human PC specimens and cell lines that coordinately promoted the worse survival of PC patients (P = 0.009). GINS2 overexpression stimulated EMT in vitro, including promoting EMT-like cellular morphology, enhancing cell motility, and activating EMT and ERK/MAPK signal pathways. However, PD98059, a specific MEK1 inhibitor, reversed GINS2 overexpression-stimulated EMT in vitro. Conversely, GINS2 silencing inhibited EMT in PANC-1 cells, which was also rescued by GINS2-GFP. Moreover, GINS2 was colocalized and co-immunoprecipitated with ERK in GINS2 high-expression Miapaca-2 and PANC-1 cells, implying a tight interaction of GINS2 with ERK/MAPK signaling. Meanwhile, GINS2 overexpression inhibited distant liver metastases in vivo, following a tight association with EMT and ERK/MAPK signaling, which was reversed by MEK inhibitor. Overexpression of GINS2 contributes to advanced clinical stage of PC patient and promotes EMT in vitro and vivo via specifically activating ERK/MAPK signal pathway.

Calreticulin promotes EMT in pancreatic cancer via mediating Ca2+ dependent acute and chronic endoplasmic reticulum stress.

BACKGROUND: Our previous study showed that calreticulin (CRT) promoted EGF-induced epithelial-mesenchymal transition (EMT) in pancreatic cancer (PC) via Integrin/EGFR-ERK/MAPK signaling. We next investigated the novel signal pathway and molecular mechanism involving the oncogenic role of CRT in PC. METHODS: We investigated the potential role and mechanism of CRT in regulating intracellular free Ca2+ dependent acute and chronic endoplasmic reticulum stress (ERS)-induced EMT in PC in vitro and vivo. RESULTS: Thapsigargin (TG) induced acute ERS via increasing intracellular free Ca2+ in PC cells, which was reversed by CRT silencing. Additionally, CRT silencing inhibited TG-induced EMT in vitro by reversing TG-induced changes of the key proteins in EMT signaling (ZO-1, E-cadherin and Slug) and ERK/MAPK signaling (pERK). TG-promoted cell invasion and migration was also rescued by CRT silencing but enhanced by IRE1α silencing (one of the key stressors in unfolded protein response). Meanwhile, CRT was co-immunoprecipitated and co-localized with IRE1α in vitro and its silencing led to the chronic ERS via upregulating IRE1α independent of IRE1-XBP1 axis. Moreover, CRT silencing inhibited IRE1α silencing-promoted EMT, including inhibiting the activation of EMT and ERK/MAPK signaling and the promotion of cell mobility. In vivo, CRT silencing decreased subcutaneous tumor size and distant liver metastasis following with the increase of IRE1α expression. A negative relationship between CRT and IRE1α was also observed in clinical PC samples, which coordinately promoted the advanced clinical stages and poor prognosis of PC patients. CONCLUSIONS: CRT promotes EMT in PC via mediating intracellular free Ca2+ dependent TG-induced acute ERS and IRE1α-mediated chronic ERS via Slug and ERK/MAPK signaling.

Musashi2 promotes the development and progression of pancreatic cancer by down-regulating Numb protein.

Musashi2-Numb interaction plays a vital role in the progression of myeloid leukemia. However, its potential role in solid cancers has rarely been reported. We investigated the coordinate function of Musashi2-Numb in the development of pancreatic cancer (PC) in vitro and vivo. Both Musashi2 protein and mRNA levels were higher in PC tissues than that in paired normal pancreas (P<0.05). Musashi2 overexpression and Numb positive expression were positively and negatively associated with tumor size and UICC stage, respectively (P<0.05). Multivariate analysis identified Musashi2 and Numb as adverse and favorable independent indicators for the survival of PC patients. Moreover, patients with high Musashi2 expression combining with negative Numb expression had a significantly worse overall survival (P=0.001). The negative relationship between Musashi2 and Numb was found at both PC tissue and cell levels. These two endogenous proteins can be co-immunoprecipitated from PC cell lines, and Musashi2 silence up-regulated Numb protein in vitro and vivo. Meanwhile, its silence decreased cell invasion and migration in vitro and inhibited the growth of subcutaneous tumors and the frequency of liver metastasis in vivo. However, Numb knockdown significantly reversed the decrease of cell invasion and migration induced by Musashi2 silence. Musashi2 promotes the development and progression of pancreatic cancer by down-regulating Numb protein. The interaction of Musashi2-Numb plays a significant role in the development and progression of PC.

Calreticulin promotes EGF-induced EMT in pancreatic cancer cells via Integrin/EGFR-ERK/MAPK signaling pathway.

Our previous study showed that Calreticulin (CRT) promoted the development of pancreatic cancer (PC) through ERK/MAPK pathway. We next investigate whether CRT promotes EGF-induced epithelial-mesenchymal transition (EMT) in PC via Integrin/EGFR-ERK/MAPK signaling, which has not been reported yet to our knowledge. EGF simultaneously induced EMT and activated Integrin/EGFR-ERK/MAPK signaling pathway in 3 PC cells. However, CRT silencing significantly inhibited EGF function, including inhibiting EGF-induced EMT-like cell morphology, EGF-enhanced cell invasion and migration, and EGF induced the decrease of E-cadherin, ZO-1, and ß-catenin and the increase of the key proteins in Integrin/EGFR-ERK/MAPK signaling (pEGFR-tyr1173, Fibronectin, Integrinß1, c-Myc and pERK). Conversely, CRT overexpression rescued the change of EMT-related proteins induced by EGF in CRT silencing PC cells. Additionally, CRT was co-stained with pEGFR1173 (with EGF), Fibronectin and Integrinß1 by IF under confocal microscopy and was co-immunoprecipitated with Fibronectin, Integrinß1 and c-Myc in both PC cells, all of which indicating a close interaction of CRT with Integrin/EGFR-ERK/MAPK signaling pathway in PC. In vivo, CRT silencing inhibited subcutaneous tumor growth and liver metastasis of pancreatic tumor. A positive relationship of CRT with Fibronectin, Integrinß1, c-Myc and pERK and a negative association of CRT with E-cad was also observed in vivo and clinical samples. Meanwhile, overexpression of the above proteins was closely associated with multiple aggressive clinicopathological characteristics and the poor prognosis of PC patients. CRT promotes EGF-induced EMT in PC cells via Integrin/EGFR-ERK/MAPK signaling pathway, which would be a promising therapy target for PC.

The origin of spontaneous synchronized burst in cultured neuronal networks based on multi-electrode arrays.

Many neural networks in mammalian central nervous system (CNS) fire single spike and complex spike burst. In fact, the conditions for triggering burst are not well understood. In the paper multi-electrode arrays (MEA) are used to record the spontaneous electrophysiological activities of cultured rat hippocampal neuronal network for a long time. After about 3 weeks culture, a transition from single spike to burst is observed in several networks. All of these spikes fire quickly before burst begins. The firing rate during the burst is lower than that just before the burst, but differences of inter-spike intervals (ISIs) between two firing patterns are not clear. Moreover, the electrical activities on neighboring electrodes show strong synchrony during the burst activities. In a word, the generation of the burst requires that network should have a sufficient level of excitation as well as a balance of synaptic inhibition.

[Effects of aniline and phenol on freshwater algae growth].

By the methods of bioassay, this paper studied the effects of aniline or phenol on the growth of Chlorella pyrenoidosa and Scenedesmus obiquus. The results showed that these two compounds had evident effects on the growth of test algae species. For the same species, aniline was more toxic. Under the same concentration of the compounds, S. obiquus was more sensitive than C. pyrenoidosa. These two algae species could degrade or absorb parts of the compounds, and phenol in particular, when their concentrations were lower.

The analysis of electrode-recording-horizon in multi-electrode array(MEA).

There is a problem that can't be ignored in the MEA collected-signal-sorting process: When a neuron positions in two adjacent microelectrodes, can its activity be detected at the same time by both microelectrodes? Under certain conditions, the contact between the electrode and the cultured cell could be simplified as capacitive contact. Because the distance and the covering area affect the capacitance the amplitude of potential decreases rapidly with the increase of distance to the microelectrode. We show that common MEA chip whose spacing of electrodes is 200 μ m can't detect the neuronal potential in its adjacent electrodes simultaneously. About 100-recorded experiments data in our lab confirm this conclusion.