Adenovirus-delivered CIAPIN1 small interfering RNA inhibits HCC growth in vitro and in vivo

Amino acid degradation pathway inhibitory by-products trigger apoptosis in CHO cells

Chinese hamster ovary (CHO) cells are widely used to produce complex biopharmaceuticals. Improving their productivity is necessary to fulfill the growing demand for such products. One way to enhance productivity is by cultivating cells at high densities, but inhibitory by-products, such as metabolite derivatives from amino acid degradation, can hinder achieving high cell densities. This research examines the impact of these inhibitory by-products on high-density cultures. We cultured X1 and X2 CHO cell lines in a small-scale semi-perfusion system and introduced a mix of inhibitory by-products on day 10. The X1 and X2 cell lines were chosen for their varied responses to the by-products; X2 was susceptible, while X1 survived. Proteomics revealed that the X2 cell line presented changes in the proteins linked to apoptosis regulation, cell building block synthesis, cell growth, DNA repair, and energy metabolism. We later used the AB cell line, an apoptosis-resistant cell line, to validate the results. AB behaved similar to X1 under stress. We confirmed the activation of apoptosis in X2 using a caspase assay. This research provides insights into the mechanisms of cell death triggered by inhibitory by-products and can guide the optimization of CHO cell culture for biopharmaceutical manufacturing.

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) accelerates vascular remodelling via p53 and JAK2-STAT3 regulation in vascular smooth muscle cells

BACKGROUND AND PURPOSE

Abnormal vascular smooth muscle cell (VSMC) proliferation and migration lead to neointima formation, which eventually results in cardiovascular hyperplastic diseases. The molecular mechanisms underlying these cellular processes have not been fully understood. Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) has been identified as an anti-apoptotic molecule, but little is known about its target genes and related pathways in VSMC dysfunction or its clinical implication in neointima formation following vascular injury.

EXPERIMENTAL APPROACH

Determination, using loss/gain-of-function approaches by gene delivery, of whether CIAPIN1 modulates VSMC proliferation, migration and neointima formation and the underlying mechanisms was carried out. Balloon injury or ligation and local delivery of lentivirus were performed on rat or mouse carotid arteries. Rat aortic smooth muscle cells, the primary cell, was used as the model to evaluate the effect of CIAPIN1 on proliferation and migration.

KEY RESULTS

CIAPIN1 was overexpressed in the neointimal region of rat arteries. CIAPIN1 deficiency markedly inhibited injury-induced or ligation-induced intimal hyperplasia and suppressed PDGF-BB-induced VSMC proliferation, migration and cell cycle progression, while overexpression promoted proliferation, migration and neointima formation. CIAPIN1 negatively regulated Tp53 transcription, which promoted cell cycle progression and migration via cyclin E1-CDK2/pRb/PCNA and the MMP2 pathway. CIAPIN1 also increased JAK2 expression, enhancing JAK2 and STAT3 phosphorylation by vascular injury, which forced phenotypic switching from contractile to synthetic state in injured arteries.

CONCLUSIONS AND IMPLICATIONS

These findings provide new insights into the mechanism by which CIAPIN1 regulates vascular remodelling and suggest a novel therapeutic target for treating vascular proliferative diseases.

Re-Evaluating the Mechanism of Action of α,β-Unsaturated Carbonyl DUB Inhibitors b-AP15 and VLX1570: A Paradigmatic Example of Unspecific Protein Cross-linking with Michael Acceptor Motif-Containing Drugs

Deubiquitinating enzymes (DUBs) are a growing target class across multiple disease states, with several inhibitors now reported. b-AP15 and VLX1570 are two structurally related USP14/UCH-37 inhibitors. Through a proteomic approach, we demonstrate that these compounds target a diverse range of proteins, resulting in the formation of higher molecular weight (MW) complexes. Activity-based proteome profiling identified CIAPIN1 as a submicromolar covalent target of VLX1570, and further analysis demonstrated that high MW complex formation leads to aggregation of CIAPIN1 in intact cells. Our results suggest that in addition to DUB inhibition, these compounds induce nonspecific protein aggregation, providing molecular explanation for general cellular toxicity.

Screening high-quality fetal bovine serum for porcine oocyte maturation in vitro

Fetal bovine serum (FBS) is widely used in cell cultures due to its high stability and easy access. It was also used as a substitute for porcine follicular fluid (PFF) in previous studies. However, FBS components are unclear, and the presence of FBS in culture media may introduce a variation from batch to batch. This study aimed to establish an effective method to screen FBS in place of PFF in the culture media for porcine oocytes in vitro. We screened FBS from different sources by using porcine fetal fibroblast cells. The effects of six FBS samples on porcine fetal fibroblast cell growth were tested via frozen cell survival assay, cell clone formation assay, cell growth curve, and cell passage activity assay. The best serum that we called GFBS (heat-inactivated FBS, cat. no. 10500-64; Gibco) showed a similar effect on the maturation and development of porcine oocytes to that of PFF and can be used as a good substitute for PFF. These results suggested that the porcine fetal fibroblast cell culture test can be used as a valuable method to screen FBS for porcine oocyte maturation and embryonic development in vitro.

CIAPIN1 Targeted NHE1 and ERK1/2 to Suppress NSCLC Cells' Metastasis and Predicted Good Prognosis in NSCLC Patients Receiving Pulmonectomy

Objective

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) acts as a downstream effector of the receptor tyrosine kinase-Ras signaling pathway and has been reported as a candidate tumor suppressor gene in various cancers. Our current study was aimed at investigating the prognostic impact of CIAPIN1 on Non-Small-Cell Lung Carcinoma (NSCLC) patients and the effect of CIAPIN1 on NSCLC A549 cells' metastasis.

Methods

Western blot analysis was applied to detect CIAPIN1 expression; Kaplan-Meier survival analysis was used to evaluate the effect of CIAPIN1 on NSCLC patients' prognosis. Wound healing assay, Transwell chamber invasion analysis, and tumorigenicity assay in BALB/c nude mice were used to measure the metastasis potential of A549 cells.

Results

We found that CIAPIN1 overexpression indicated good survival duration during the follow-up period. CIAPIN1 overexpression inhibited the migration, invasion, MMPs, and EMT-associated markers in A549 cells. Further, NHE1 (Na+/H+ exchanger 1) expression and ERK1/2 phosphorylation decreased along with CIAPIN1 upregulation. Importantly, treating A549 cells with CIAPIN1 overexpression with the NHE1-specific inhibitor, Cariporide, further inhibited the metastatic capacity, MMP expression, EMT-associated markers, and phosphorylated ERK1/2. Treatment with the MEK1-specific inhibitor, PD98059, induced nearly the same suppression of CIAPIN1 overexpression-dependent metastatic capacity, MMP expression, and EMT-associated markers as was observed with Cariporide. Further, Cariporide and PD98059 exert synergistical suppression of A549 cells' metastatic capacity.

Conclusion

Thus, the current results implied a potential management by which CIAPIN1 upregulation may have a crucial effect on the suppression of NSCLC, indicating that overexpression of CIAPIN1 might serve as a combination with chemotherapeutical agents in NSCLC therapy.

MiRNA-195-5p Functions as a Tumor Suppressor and a Predictive of Poor Prognosis in Non-small Cell Lung Cancer by Directly Targeting CIAPIN1

Accumulating evidence suggests that microRNAs (miRNAs) has been proven to be a critical regulator in the tumor progression, of which miR-195-5p was reported to function as tumor suppressor in prostate cancer and oral squamous cell carcinoma. However, studies on the clinical significance and biological function of miR-195-5p in non-small cell lung cancer (NSCLC) were still unavailable. Here, we reported that the expression of miR-195-5p was decreased in NSCLC tissues and cell lines. Downregulation of miR-195-5p was significantly associated with TNM stage, tumor size and lymph node metastasis. The Kaplan-Meier survival analysis demonstrated that the survival time of NSCLC patients with high expression of miR-195-5p was longer than those with low expression during the 5-year follow up period (p = 0.0410). COX regression analysis indicated that miR-195-5p expression was an independent prognostic indicator for the survival of NSCLC patients (HR = 2.45, 95% CI: 1.53–4.63; p = 0.007). Results of functional analyses revealed that overexpression of miR-195-5p in A549 cells inhibited cell proliferation, induced cell cycle G0/G1 phase arrest and apoptosis using MTT and flow cytometry analysis. Furthermore, bioinformatics and luciferase reporter assays demonstrated that cytokine-induced apoptosis inhibitor 1 (CIAPIN1), an anti-apoptotic molecule was a direct target of miR-195-5p in NSCLC cells. Meta-analysis based on Oncomine database showed CIAPIN1 was significantly up-regulated in human lung cancer tissues. Consistently, knockdown of CIAPIN1 phenocopied the inhibitory effects of miR-195-5p overexpression in NSCLC cell function. These findings suggest that miR-195-5p could be used as a potential prognostic predictor and tumor suppressor in NSCLC.

Genotoxicity and mutagenicity assessment of food contaminant mixtures present in the French diet

Through diet, people are exposed simultaneously to a variety of contaminants (e.g. heavy metals, mycotoxins, pesticides) that could have combined adverse effects on human health. A previous study identified six main mixtures of food contaminants to which French adult consumers are exposed. These complex mixtures are comprised of 11 to 19 chemicals that have numerous toxic properties. In the present study, we investigated the genotoxic effects of these food contaminants, as single molecules and in mixtures that reflect their occurrence in the French diet, using the γH2AX assay in two human cell lines (HepG2, LS-174 T). Results of detailed analysis of the 49 individual contaminants (including 21 tested in this study) demonstrated a positive genotoxic response to 14 contaminants in HepG2 and 12 in LS-174 T cells. Next, our results indicated that two mixtures out of six triggered significant γH2AX induction after 24 hr of treatment, at concentrations for which individual compounds did not induce any DNA damage, suggesting more than additive interactions between chemicals. γH2AX positive mixtures were then tested for mutagenicity with the innovative in vitro PIG-A assay in HepG2 cells coupled with the soft agar colony formation assay. The two γH2AX positive mixtures led to a significant increase in the frequency of PIG-A GPI-deficient cells and in the number of colonies formed in soft agar. In conclusion, our study demonstrates that two mixtures of contaminants present in the French diet induce genotoxicity and mutagenicity, and that the combined effects of single molecules present in these mixtures are likely not additive, highlighting potential problems for hazard assessment of mixtures. Environ. Mol. Mutagen. 59:742-754, 2018. © 2018 Wiley Periodicals, Inc.

FOXO1 associated with sensitivity to chemotherapy drugs and glial-mesenchymal transition in glioma

Mesenchymal subtype of glioblastoma (GBM), identified as one of four clinically relevant molecular subtypes, has worst prognosis because of its close relation with the malignant biological properties induced by glial-mesenchymal transition (GMT). However, the molecular mechanism of GMT and its characterized molecule of GBM have not been studied. Forkhead box protein O1 (FOXO1) is at a convergence point of receptor tyrosine kinase signaling as one of the three core pathways implicated in GBM. Our previous study indicated that the inactivation of FOXO1 involved in the inhibition of GMT is an independent prognosis factor of GBM. In this study, we will further confirm the role of FOXO1 in GMT through cytological experiments to clarify how FOXO1 regulates GMT and its clinical significance. We established virus-infected FOXO1 overexpression and FOXO1 knockdown cells of U373 MG and U251 mediated by lentivirus, based on the effect of which FOXO1-correlated-GMT experiments were performed in vitro and in vivo. Our data suggested that FOXO1 played a crucial role in resistance to TMZ, BCNU, and CDDP; migration and invasion; and stem cell properties of glioma cells. FOXO1 may serve as a targeted biomarker for prediction of sensitivity to chemotherapy drugs, metastasis, and prognosis, which provides a new idea for mesenchymal GBM treatment.

Target-specific delivery of siRNA into hepatoma cells' cytoplasm by bifunctional carrier peptide

RNA interference (RNAi) is among the most potential approach for the therapy of hepatocellular carcinoma and the major barrier hindering siRNA therapeutics is the low efficiency of delivery to the desired cells. The current study aimed at developing a novel peptide for more efficient hepatoma targeted siRNA delivery, by combining luteinizing hormone-releasing hormone with hepatoma targeting specificity and MPG^△NLS with cytoplasm-delivery tendency. The developed bifunctional peptide LHRH-MPG^△NLS and siRNA were mixed together and resulted in LHRH-MPG^△NLS/siRNA polyplexes through self-assembly. The polyplexes were characterized by agarose gel retardation and dynamic light scatting analysis. Hepatoma targeting specificity was analyzed with the GE IN Cell Analyzer 2000 High-Content Cellular Analysis System after cell transfection, and the effect of RNA interference was detected by RT-PCR. The results demonstrated that LHRH-MPG^△NLS was able to assemble with siRNA to form stable and nano-sized peptide/siRNA polyplexes, which could inhibit the expression of the target gene and was essentially non-cytotoxic, as compared with the commercial transfection reagent lipofectamine 2000.

MicroRNA-140-5p inhibits hepatocellular carcinoma by directly targeting the unique isomerase Pin1 to block multiple cancer-driving pathways

Hepatocellular carcinoma (HCC) is the second leading cause of cancer related-death. As a major common regulator of numerous cancer-driving pathways and a unique therapeutic target, the prolyl isomerase Pin1 is overexpressed in a majority of HCCs, whereas the mechanism underlying Pin1 overexpression remains elusive. Here we find that miR-140-5p inhibits HCC by directly targeting Pin1 to block multiple cancer-driving pathways. Bioinformatics analysis, miRNA binding and functional assays identify that miR-140-5p directly interacts with the 3′UTR of Pin1 and inhibits Pin1 translation. Furthermore, like stable Pin1 knockdown, moderate overexpression of miR-140-5p not only eliminates Pin1, but also inhibits cells growth and metastasis. Importantly, these effects of miR-140-5p are largely rescued by reconstitution of Pin1. Moreover, miR-140-5p inhibits multiple Pin1-dependent cancer pathways and suppresses tumor growth in mice. The clinical significance of these findings has been substantiated by the demonstrations that miR-140-5p is frequently down-regulated and inversely correlated with Pin1 overexpression in HCC tissues and cell lines. Given prevalent miR-140-5p downregulation in other cancers and major impact of Pin1 overexpression on activating numerous cancer-driving pathways including global miRNA downregulation, the miR-140-5p/Pin1 axis may play a major role in tumorigenesis and offer promising therapeutic targets for HCC and other cancers.

Quantum dot-based molecular imaging of cancer cell growth using a clone formation assay

This aim of the present study was to investigate clonal growth behavior and analyze the proliferation characteristics of cancer cells. The MCF‑7 human breast cancer cell line, SW480 human colon cancer cell line and SGC7901 human gastric cancer cell line were selected to investigate the morphology of cell clones. Quantum dot‑based molecular targeted imaging techniques (which stained pan‑cytokeratin in the cytoplasm green and Ki67 in the cell nucleus yellow or red) were used to investigate the clone formation rate, cell morphology, discrete tendency, and Ki67 expression and distribution in clones. From the cell clone formation assay, the MCF‑7, SW480 and SGC7901 cells were observed to form clones on days 6, 8 and 12 of cell culture, respectively. These three types of cells had heterogeneous morphology, large nuclear:cytoplasmic ratios, and conspicuous pathological mitotic features. The cells at the clone periphery formed multiple pseudopodium. In certain clones, cancer cells at the borderline were separated from the central cell clusters or presented a discrete tendency. With quantum dot‑based molecular targeted imaging techniques, cells with strong Ki67 expression were predominantly shown to be distributed at the clone periphery, or concentrated on one side of the clones. In conclusion, cancer cell clones showed asymmetric growth behavior, and Ki67 was widely expressed in clones of these three cell lines, with strong expression around the clones, or aggregated at one side. Cell clone formation assay based on quantum dots molecular imaging offered a novel method to study the proliferative features of cancer cells, thus providing a further insight into tumor biology.

Knock-down of CIAPIN1 sensitizes K562 chronic myeloid leukemia cells to Imatinib by regulation of cell cycle and apoptosis-associated members via NF-κB and ERK5 signaling pathway

CIAPIN1 (cytokine-induced apoptosis inhibitor 1) was recently identified as an essential downstream effector of the Ras signaling pathway. However, its potential role in regulating myeloid leukemia cells sensitivity to Imatinib remains unclear. In this study, we found depletion of CIAPIN1 inhibited proliferation and triggered more apoptosis of K562CML (chronic myeloid leukemia) cells with or without Imatinib treatment. Meanwhile, CIAPIN1 depletion decreased ERK5 phosphorylation and NF-κB activity. Importantly, treating CIAPIN1-depleted K562 cells with ERK5 signaling pathway specific inhibitor, XMD8-92, further inhibited proliferation and promoted apoptosis with or without Imatinib treatment. Treatment with the NF-κB specific inhibitor, Bay 11-7082, induced nearly the same inhibition of proliferation and promotion of apoptosis conferred by CIAPIN1 depletion as was observed with XMD8-92 treatment. Further, XMD8-92 and Bay 11-7082 synergistically inhibited proliferation and promoted apoptosis of CIAPIN1-depleted K562 cells with or without Imatinib treatment. The nude mice transplantation model was also performed to confirm the enhanced sensitivity of CIAPIN1-depleted K562 cells to Imatinib. Thus, our results provided a potential management by which CIAPIN1 knock-down might have a crucial impact on enhancing sensitivity of K562 cells to Imatinib in the therapeutic approaches, indicating that CIAPIN1 knock-down might serve as a combination with chemotherapeutical agents in leukemia diseases therapy.

Cancer-Related NEET Proteins Transfer 2Fe-2S Clusters to Anamorsin, a Protein Required for Cytosolic Iron-Sulfur Cluster Biogenesis

Iron-sulfur cluster biogenesis is executed by distinct protein assembly systems. Mammals have two systems, the mitochondrial Fe-S cluster assembly system (ISC) and the cytosolic assembly system (CIA), that are connected by an unknown mechanism. The human members of the NEET family of 2Fe-2S proteins, nutrient-deprivation autophagy factor-1 (NAF-1) and mitoNEET (mNT), are located at the interface between the mitochondria and the cytosol. These proteins have been implicated in cancer cell proliferation, and they can transfer their 2Fe-2S clusters to a standard apo-acceptor protein. Here we report the first physiological 2Fe-2S cluster acceptor for both NEET proteins as human Anamorsin (also known as cytokine induced apoptosis inhibitor-1; CIAPIN-1). Anamorsin is an electron transfer protein containing two iron-sulfur cluster-binding sites that is required for cytosolic Fe-S cluster assembly. We show, using UV-Vis spectroscopy, that both NAF-1 and mNT can transfer their 2Fe-2S clusters to apo-Anamorsin with second order rate constants similar to those of other known human 2Fe-2S transfer proteins. A direct protein-protein interaction of the NEET proteins with apo-Anamorsin was detected using biolayer interferometry. Furthermore, electrospray mass spectrometry of holo-Anamorsin prepared by cluster transfer shows that it receives both of its 2Fe-2S clusters from the NEETs. We propose that mNT and NAF-1 can provide parallel routes connecting the mitochondrial ISC system and the CIA. 2Fe-2S clusters assembled in the mitochondria are received by NEET proteins and when needed transferred to Anamorsin, activating the CIA.

Molecular cloning, expression and functional characterization of a teleostan cytokine-induced apoptosis inhibitor from rock bream (Oplegnathus fasciatus)

Apoptosis plays a key role in the physiology of multicellular organisms and is regulated by different promoting and inhibitory mechanisms. Cytokine-induced apoptotic inhibitor (CIAPI) was recently identified as a key factor involved in apoptosis inhibition in higher vertebrate lineages. However, most of the CIAPIs of lower vertebrate species are yet to be characterized. Herein, we molecularly characterized a teleostan counterpart of CIAPI from rock bream (Oplegnathus fasciatus), designating as RbCIAPI. The complete coding region of RbCIAPI was consisted of 942 nucleotides encoding a protein of 313 amino acids with a predicted molecular mass of ~33 kDa. RbCIAPI gene exhibited a multi-exonic architecture, consisting 9 exons interrupted by 8 introns. Protein sequence analysis revealed that RbCIAPI shares significant homology with known CIAPI counterparts, and phylogenetic reconstruction confirmed its closer evolutionary relationship with its fish counterparts. Ubiquitous spatial distribution of RbCIAPI was detected in our quantitative real time polymerase chain reaction (qPCR) analysis, where more prominent expression levels were observed in the blood and liver tissues. Moreover, the RbCIAPI basal transcription level was found to be modulated by different bacterial and viral stimuli, which could be plausibly supported by our previous observations on the transcriptional modulation of the caspase 3 counterpart of rock bream (Rbcasp3) in response to the same stimuli. In addition, our in vitro functional assay demonstrated that recombinant RbCIAPI could detectably inhibit the proteolysis activity of recombinant Rbcasp3. Collectively, our preliminary results suggest that RbCIAPI may play an anti-apoptotic role in rock bream physiology, likely by inhibiting the caspase-dependent apoptosis pathway. Therefore, RbCIAPI potentially plays an important role in host immunity by regulating the apoptosis process under pathogenic stress.

Prognostic significance of Nemo-like kinase expression in patients with hepatocellular carcinoma

Nemo-like kinase (NLK) is an evolutionarily conserved serine/threonine protein kinase and belongs to the extracellular signal-regulated kinases/microtubule-associated protein kinase families (Erks/MAPKs). Previous studies have indicated that abnormal expressions of NLK played critical roles in various types of human cancers. Recent studies suggested that NLK expression was significantly upregulated in the hepatocellular carcinoma (HCC) specimens. However, the clinical significance of NLK expression in HCC remains largely unknown. In this study, we focused on the clinical significance of NLK in HCC and found that high expression of NLK was significantly associated with Edmondson-Steiner grade (P = 0.002), tumor size (P = 0.022), and no. of tumor nodules (P < 0.001), and NLK was positively correlated with proliferation marker Ki-67 (P < 0.01). Univariate analysis suggested that NLK expression was associated with poor prognosis (P < 0.001). Multivariate analysis indicated that NLK expression was an independent prognostic indicator for HCC (P = 0.0370). In conclusion, NLK overexpression is associated with poor overall survival in patients with HCC, it might be an independent poor prognostic marker for HCC.

Expression of RhoGDI2 and CIAPIN1 in gastric carcinoma

AIM: To detect the expression of RhoGTPase dissociation inhibitor 2 (RhoGDI2) and cytokine-induced apoptosis inhibitor 1 (CIAPIN1) in gastric cancer and to analyze their clinical significance.

METHODS: Immunohistochemistry was used to detect the expression of RhoGDI2 and CIAPIN1 in 94 gastric cancer specimens.

RESULTS: The positive rates of RhoGDI2 and CIAPIN1 in gastric cancer were 67.02% and 77.66%, respectively. The expression of RhoGDI2 and CIAPIN1 was related to tumor differentiation, depth of invasion, lymph node metastasis, distant metastasis and TNM stage in gastric cancer. There was a positive correlation between the expression of RhoGDI2 and that of CIAPIN1.

CONCLUSION: The expression of RhoGDI2 is correlated with that of CIAPIN1 in gastric cancer. CIAPIN1 is very likely to be regulated by RhoGDI2, and functions as a downstream target gene of RhoGDI2 in tumor invasion and metastasis. Both of them may be involved in regulating the invasion and metastasis of gastric cancer.

MGr1-Ag/37LRP promotes growth and proliferation of gastric cancer in vitro and in vivo

Gastric carcinoma (GC) is an aggressive cancer with a poor prognosis. We previously reported that MGr1-Ag was involved in multidrug resistance and anti-apoptosis in GC. However, the exact function of MGr1-Ag in GC proliferation is not clear. In this study, we found that MGr1-Ag was highly expressed in GC tissues and four GC cell lines compared with nontumor gastric tissues or gastric epithelial mucosa cells. The high expression of MGr1-Ag/37LRP was also consistent with the decreased median survival time of GC patients. We employed lenti-mediated RNA interference technique to knock down MGr1-Ag expression in SGC7901 and MKN45 cells, respectively, and observed its effects on GC cells growth in vitro and in vivo. Further study showed that knockdown of MGr1-Ag could inhibit GC cell proliferation by inhibiting the cell cycle S-phase entry and induced apoptosis. Soft agar colony formation assay indicated that the colony formation ability of SGC7901 and MKN45 cells decreased after lenti-MGr1-Ag small interfering RNA (siRNA) infection. Western blot revealed that cyclin D1 and Bcl-2 expression were downregulated whereas p27 and Bax were upregulated in lenti-MGr-siRNA-infected GC cells. Further study demonstrated that the proliferation effect of MGr1-Ag in GC is dependent on its laminin-binding region. Taken together, these data revealed a novel function of MGr1-Ag that can possibly be used as an independent prognostic factor and a potential therapeutic target for GC.

TAT-LHRH conjugated low molecular weight chitosan as a gene carrier specific for hepatocellular carcinoma cells

To develop a chitosan-based nonviral gene carrier capable of delivering genes specifically into hepatoma cells, a bifunctional peptide composed of the TAT (transactivator of transcription) peptide and luteinizing hormone-releasing hormone (LHRH) was conjugated with low molecular weight chitosan, resulting in a TAT-LHRH-chitosan conjugate (TLC). TLC/DNA nanoparticles (TLCDNPs) were characterized by agarose gel retardation, atomic force microscopy, and dynamic light scattering analysis. In vitro targeting specificity and transfection efficiency were analyzed with a GE IN Cell Analyzer 2000 High-Content Cellular Analysis System. The results demonstrated that TLC had stronger DNA condensing power than unmodified chitosan, and that TLCDNPs were of roughly round shape with average diameter of 70-85 nm and zeta potential of +30 mV and were relatively stable in solution. The in vitro study demonstrated TLC was highly selective for hepatoma cells and essentially nontoxic.

MiR-612 suppresses the stemness of liver cancer via Wnt/β-catenin signaling

Previous research showed that microRNA-612 (miR-612) has inhibitory effects on cell proliferation, migration, invasion, and metastasis of hepatocellular carcinoma (HCC). AKT2 was confirmed to be a direct target of miR-612, through which the epithelial-mesenchymal transition (EMT) and metastasis of HCC were inhibited. Our present findings reveal that miR-612 is able to suppress the stemness of HCC by reducing the number and size of tumorspheres as well as clone formation in soft agar, and to relieve drug resistance to cisplatin and 5-fluorouracil. In addition, miR-612 hampered the capacity of tumorigenesis in NOD/SCID mice and redistributed the tumor invasive frontier of miR-612-modulating cells. Finally, our findings suggest that Wnt/β-catenin signaling is required in the regulation of EMT-associated stem cell-like traits by miR-612.

The anti-apoptotic gene Anamorsin is essential for both autonomous and extrinsic regulation of murine fetal liver hematopoiesis

Anamorsin (AM) is an antiapoptotic molecule that confers factor-independent survival on hematopoietic cells. AM-deficient (AM(-/-)) mice are embryonic lethal because of a defect in definitive hematopoiesis; however, the significance of AM in embryonic hematopoiesis remains unknown. This study characterized the hematopoietic defects in AM(-/-) fetal livers. The AM(-/-) fetal liver displayed significantly reduced numbers of c-Kit(+)Sca-1(+)Lin(-) (KSL) cells. An in vitro colony-forming unit assay showed that fetal liver cells isolated from AM(-/-) embryos gave rise to fewer colonies in all cell types. The reconstitution activity in AM(-/-) hematopoietic stem cells (HSCs) was markedly reduced in all lineages. Furthermore, the limiting dilution assay revealed that the number of fetal liver HSCs was reduced because of AM deficiency. Retrovirus-mediated AM expression rescued the defective hematopoietic colony-forming activities of AM(-/-) KSL cells. We also investigated the effects of AM deficiency on fetal liver stromal cells, which support hematopoiesis. Interestingly, primary stromal cell cultures from wild type fetal liver supported the growth of AM(-/-) KSL cells, but stromal cultures from AM(-/-) fetal liver provided little support of wild type KSL cell growth. These results demonstrated that AM was essential for both autonomous and extrinsic regulation of fetal liver hematopoiesis. This study provided new insight into the molecular regulation of hematopoiesis.

A combination of two electrophoretical approaches for detailed proteome-based characterization of SCLC subtypes

CONTEXT

Small cell lung cancers (SCLC) are heterogeneous and tumours differ in growth characteristics and treatment resistance.

OBJECTIVE

To get insight into the underlying protein profiles responsible for this heterogeneity, two subtypes of SCLC cells mutually differing in chemo resistance properties and growth characteristics are analysed.

MATERIALS AND METHODS

Two different electrophoresis approaches in combination with mass spectrometry were used to detect differences between the SCLC cell lines GLC1 and GLC1M13: IEF/SDS-PAGE as well as cetyltrimethylammonium bromide (CTAB)-SDS-PAGE.

RESULTS

Altogether 60 non redundant differentially expressed proteins were found of which 5 were verified by Western Blot analysis.

DISCUSSION

Most of these proteins identified are involved in processes of tumour progression. Therefore, these proteins are interesting candidates for further functional analysis.

CONCLUSION

Additional CTAB-SDS page is a complementary method to IEF-SDS page revealing a complete new subset of proteins differentially expressed between GLC1 and GLC1 M13 cells SCLC subtypes.

Down regulation of CIAPIN1 reverses multidrug resistance in human breast cancer cells by inhibiting MDR1

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1), initially named anamorsin, a newly indentified antiapoptotic molecule is a downstream effector of the receptor tyrosine kinase-Ras signaling pathway. Current study has revealed that CIAPIN1 may have wide and important functions, especially due to its close correlations with malignant tumors. However whether or not it is involved in the multi-drug resistance (MDR) process of breast cancer has not been elucidated. To explore the effect of CIAPIN1 on MDR, we examined the expression of P-gp and CIAPIN1 by immunohistochemistry and found there was positive correlation between them. Then we successfully interfered with RNA translation by the infection of siRNA of CIAPIN1 into MCF7/ADM breast cancer cell lines through a lentivirus, and the expression of the target gene was significantly inhibited. After RNAi the drug resistance was reduced significantly and the expression of MDR1mRNA and P-gp in MCF7/ADM cell lines showed a significant decrease. Also the expression of P53 protein increased in a statistically significant way (p ≤ 0.01) after RNAi exposure. In addition, flow cytometry analysis reveals that cell cycle and anti-apoptotic enhancing capability of cells changed after RNAi treatment. These results suggested CIAPIN1 may participate in breast cancer MDR by regulating MDR1 and P53 expression, changing cell cycle and enhancing the anti-apoptotic capability of cells.

CIAPIN1 nuclear accumulation predicts poor clinical outcome in epithelial ovarian cancer

Background

Epithelial ovarian cancer (EOC) is an aggressive disease with poor prognosis. The expression of cytokine-induced apoptosis inhibitor 1 (CIAPIN1) correlates with the malignant progression of several cancers. However, the relationship between the subcellular localization of CIAPIN1 and clinical characteristics in EOC remains unclear.

Methods

Immunohistochemistry was performed to detect CIAPIN1 expression in 108 EOC tissues. CIAPIN1 expressions in eight fresh EOC tissues were detected by Western blotting. The relationship between CIAPIN1 subcellular expression and patients’ clinicopathological features, including prognosis, was evaluated. Immunohistochemistry and immunofluorescence were employed to assess the CIAPIN1 subcellular localization in the EOC cell lines A2780 and HO8910. In addition, all patients were followed up to assess the prognostic value of CIAPIN1 in patients with EOC.

Results

CIAPIN1 is highly expressed in EOC, but is present at low levels in paired non-cancerous ovarian epithelial tissues. The results of Western blotting were in accordance with the immunohistochemical results. Poor differentiation of the tumors and EOC cell lines correlated with higher levels of CIAPIN1 nuclear expression. CIAPIN1 nuclear expression significantly correlated with the Federation International of Gynecology and Obstetrics (FIGO) stage and histological differentiation (P = 0.034 and P < 0.0001, respectively). Moreover, nuclear localization of CIAPIN1 was selected as an unfavorable prognostic factor by both univariate and multivariate analyses ( P < 0.001). However, no significant correlations were observed between cytoplasmic localization of CIAPIN1 and clinicopathological parameters.

Conclusions

CIAPIN1 might play a crucial role in the differentiation of EOC cells. Elevated expression of nuclear CIAPIN1 negatively correlated with the survival of EOC patients, suggesting that nuclear CIAPIN1 might serve as a prognostic biomarker for EOC patients.

Overexpression of CIAPIN1 inhibited pancreatic cancer cell proliferation and was associated with good prognosis in pancreatic cancer

Cytokine-induced antiapoptotic molecule (CIAPIN1), a newly identified apoptosis inhibitor, has been found to participate in the process of proliferation and tumorigenicity for several cancers. The aim of this study was to evaluate the prognostic value of CIAPIN1 in pancreatic cancer and to probe its function in pancreatic carcinogenesis. We found that CIAPIN1 protein was absent or reduced in pancreatic cancer cell lines. There was also a loss or decrease in CIAPIN1 expression in 118 cases of pancreatic cancer tissues as compared with that in 82 cases of normal pancreatic tissues. In a Cox proportional hazards model, CIAPIN1 expression independently predicted better survival (P<0.0001). Adenoviral-mediated restoration of CIAPIN1 expression greatly repressed the proliferation of pancreatic cancer cell in vitro and suppressed the tumorigenicity of pancreatic cancer cell in Balb/c nude mice. Our data also revealed that inhibition of pancreatic cancer cells proliferation by enforcing CIAPIN1 expression at least partly through delaying cell cycle progression and inducing cell apoptosis. In summary, our work revealed a novel function of CIAPIN1, which might possibly be used as an independent prognostic factor and a potential therapeutic target for pancreatic cancer.

Proteomics-based strategy to delineate the molecular mechanisms of RhoGDI2-induced metastasis and drug resistance in gastric cancer

Rho GDP dissociation inhibitor 2 (RhoGDI2) was initially identified as a regulator of the Rho family of GTPases. Our recent works suggest that RhoGDI2 promotes tumor growth and malignant progression, as well as enhances chemoresistance in gastric cancer. Here, we delineate the mechanism by which RhoGDI2 promotes gastric cancer cell invasion and chemoresistance using two-dimensional gel electrophoresis (2-DE) on proteins derived from a RhoGDI2-overexpressing SNU-484 human gastric cancer cell line and control cells. Differentially expressed proteins were identified using matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOF-MS). In total, 47 differential protein spots were identified; 33 were upregulated, and 14 were downregulated by RhoGDI2 overexpression. Upregulation of SAE1, Cathepsin D, Cofilin1, CIAPIN1, and PAK2 proteins was validated by Western blot analysis. Loss-of-function analysis using small interference RNA (siRNA) directed against candidate genes reveals the need for CIAPIN1 and PAK2 in RhoGDI2-induced cancer cell invasion and Cathepsin D and PAK2 in RhoGDI2-mediated chemoresistance in gastric cancer cells. These data extend our understanding of the genes that act downstream of RhoGDI2 during the progression of gastric cancer and the acquisition of chemoresistance.

RPB5-mediating protein is required for the proliferation of hepatocellular carcinoma cells

RPB5-mediating protein (RMP) is associated with the RNA polymerase II subunit RPB5. RMP functionally counteracts the transcriptional activation of hepatitis B virus X protein that has been shown to play a role in the development of hepatocellular carcinoma (HCC). However, the effect of RMP on the growth of HCC remains unclear. In this study, we characterized the potential role of RMP in the proliferation of human HCC cells using two cell lines, SMMC-7721 and HepG2. We found that RMP expression increased when HCC cells were treated with (60)Co γ-irradiation. Cell growth and colony formation assays suggest that RMP plays an antiapoptotic role in the proliferation and growth of HCC cells. We also show that RMP depletion induced the G(2) arrest of HCC cells characterized by the decreased expression of Cdk1 and Cyclin B. Tumor formation assays further confirmed the in vivo requirement of RMP during HCC growth. In conclusion, our results demonstrate that RMP is a radiation-sensitive factor, and it may play essential roles in HCC growth by affecting the proliferation and apoptosis of HCC cells.

Expression of CIAPIN1 in human colorectal cancer and its correlation with prognosis

Background

The cytokine-induced anti-apoptotic molecule (CIAPIN1) had been found to be a differentially-expressed gene involved in a variety of cancers, and it was also considered as a candidate tumour suppressor gene in gastric cancer, renal cancer and liver cancer. However, studies on the role of CIAPIN1 in colorectal cancer were still unavailable. The aim of this study was to determine the prognostic impact of CIAPIN1 in 273 colorectal cancer (CRC) samples and to investigate the CIAPIN1 expression in CRC cell lines after inducing differentiation.

Methods

Immunohistochemical analysis was performed to detect the expression of CIAPIN1 in CRC samples from 273 patients. The relationship between CIAPIN1 expression and patients' characteristics (gender, age, location of cancer, UICC stage, local recurrence and tumour grade factors) was evaluated. In addition, these patients were followed up for five consecutive years to investigate the relationship between CIAPIN1 expression and the prognosis of CRC. We induced the differentiation of the CRC cell lines HT29 and SW480, in order to detect the expression of CIAPIN1 in the process of CRC cells differentiation.

Results

Results indicated that CIAPIN1 was mainly expressed in the cytoplasm and nucleus, and that its expression level in cancer samples was significantly lower than in normal tissues. The Wilcoxon-Mann-Whitney test showed a significant difference in the differential expression of CIAPIN1 in patients with different T and UICC stages, and tumour grade (P = 0.0393, 0.0297 and 0.0397, respectively). The Kaplan-Meier survival analysis demonstrated that the survival time of CRC patients with high expression of CIAPIN1 was longer than those with low expression during the 5-year follow up period (P = 0.0002). COX regression analysis indicated that low expression of CIAPIN1, cancer stage of > pT1, distant organ metastasis (pM₁), regional lymph node metastasis (> pN₁) and local recurrence (yes) were independent, poor prognostic factors of CRC (P = 0.012, P = 0.032, P <0.001, P <0.001, P <0.001 respectively). Both Western blotting and RT-PCR showed that CIAPIN1 expression was increased with the degree of differentiation of HT29 and SW480 cells.

Conclusions

CIAPIN1 played an important role in the differentiation of CRC cells, and the differential expression of CIAPIN1 in CRC was closely related to prognosis.

Potential use of RNA interference in cancer therapy

RNA interference (RNAi) is an evolutionary conserved mechanism for specific gene silencing. This mechanism has great potential for use in targeted cancer therapy. Understanding the RNAi mechanism has led to the development of several novel RNAi-based therapeutic approaches currently in the early phases of clinical trials. It remains difficult to effectively deliver the nucleic acids required in vivo to initiate RNAi, and intense effort is under way in developing effective and targeted systemic delivery systems for RNAi. Description of in vivo delivery systems is not the focus of this review. In this review, we cover the rationale for pursuing personalised cancer therapy with RNAi, briefly review the mechanism of each major RNAi therapeutic technique, summarise and sample recent results with animal models applying RNAi for cancer, and provide an update on current clinical trials with RNAi-based therapeutic agents for cancer therapy. RNAi-based cancer therapy is still in its infancy, and there are numerous obstacles and issues that need to be resolved before its application in personalised therapy focusing on patient-cancer-specific targets can become standard cancer treatment, either alone or in combination with other treatments.

CIAPIN1 as a therapeutic target in cancer

IMPORTANCE OF THE FIELD

Cytokine-induced apoptosis inhibitor 1 (CIAPIN1) is a newly identified cytokine-induced apoptosis inhibitor, which has roles in cell division and angiogenesis. Owing to its prognostic value for human tumors and involvement in cancer progression and tumor cell resistance to anticancer agents, CIAPIN1 has been proposed as an attractive target for new anticancer interventions.

AREAS COVERED IN THIS REVIEW

We define CIAPIN1's potential function as a new therapeutic target for anticancer interventions and this review covers all related literature on CIAPIN1 in cancer from the past 5 years

WHAT THE READER WILL GAIN

Several preclinical studies have demonstrated that CIAPIN1 is associated with chemotherapy resistance, increased tumor recurrence and shorter patient survival in different human tumor models, making anti-CIAPIN1 therapy an attractive cancer treatment strategy. Recent studies also suggest that CIAPIN1 is expressed at low levels in some types of malignant tumors and that its overexpression may inhibit their proliferation or tumorigenesis.

TAKE HOME MESSAGE

Considering that the exact expression and function of CIAPIN1 are still not well characterized and understood, better knowledge of CIAPIN1 in normal versus tumor tissues will be instrumental for the design of optimal strategies to selectively disrupt CIAPIN1 in cancer.

ATR3 encodes a diflavin reductase essential for Arabidopsis embryo development

*The Arabidopsis genome possesses two confirmed Cytochrome P450 Reductase (CPR) genes, ATR1 and ATR2, together with a third putative homologue, ATR3, which annotation is questionable. *Phylogenetic analysis classified ATR3 as a CPR-like protein sharing homologies with the animal cytosolic dual flavin reductases, NR1 and Fre-1, distinct from the microsomal CPRs, ATR1 and ATR2. Like NR1 and Fre-1, ATR3 lacks the N-terminal endoplasmic reticulum (ER) anchor domain of CPRs and is localized in the cytoplasm. Recombinant ATR3 in plant soluble extracts was able to reduce cytochrome c but failed to reduce the human P450 CYP1A2. *Loss of ATR3 function resulted in early embryo lethality indicating that this reductase activity is essential. A yeast 2-hybrid screen identified a unique interaction of ATR3 with the homologue of the human anti-apoptotic CIAPIN1 and the yeast Dre2 protein. *This interaction suggests two possible roles for ATR3 in the control of cell death and in chromosome segregation at mitosis. Consistent with these results, the promoter of ATR3 is activated during cell cycle progression. Together these results demonstrated that ATR3 belongs to the NR1 subfamily of diflavin reductases whose characterized members are involved in essential cellular functions.

Comparison of colony-forming capacity of HepG2 cells in different soft agar systems

AIM: To determine the optimal cell density and agar concentration for separation of cell clones and thereby provide a reference for screening of tumor stem cells.

METHODS: HepG2 cells were mixed with 10 g/L agarose and inoculated in 2 g/L (group A) and 3 g/L (group B) soft agar at different densities. After 14 d of culture, the number of cell clones was counted and the rate of colony formation was calculated.

RESULTS: The number of clones formed in group A was significantly higher than that in group B (t = 4.36, P < 0.05). The rates of colony formation observed in both group A and group B increased with the increase in cell density that varied between 100 and 500 cells per well. In contrast, the rate of colony formation decreased with the increase in cell density that varied between 600 and 1000 cells per well.

CONCLUSION: The optimal concentration of agar in the upper layer for colony formation is 3 g/L, with 10% agarose as a stock agar. The maximum rate of colony formation is achieved when cells are inoculated at a density of 500 cells per well.

Programmed cell death 4 (PDCD4) suppresses metastastic potential of human hepatocellular carcinoma cells

BACKGROUND

Hepatocellular carcinoma (HCC) is a lethal malignancy with high rate of metastasis and poor prognosis. There are no effective managements to block metastasis of HCC. Programmed cell death 4 (PDCD4) is found to be a tumor transformation suppressor. Among investigations on effects of PDCD4, little is about the metastatic potentials of HCC cells. This study was to investigate the role of PDCD4 on metastatic potential of human HCC cells.

METHODS

We examined the expression of PDCD4 in three HCC cell lines with different metastatic potentials, MHCC-97H (high metastatic potential), MHCC-97L (low metastatic potential) and Hep3B (no metastatic potential). A plasmid encoding PDCD4 gene was constructed and then transfected into HCC cells with the lowest PDCD4 expression level. Effects of PDCD4 on cell proliferation, cell apoptosis, gene expression of metastasis tumor antigen 1 (MTA1) and in vitro migration and invasion capacity were assessed after transfection.

RESULTS

Our results showed that the expression level of PDCD4 was inversely correlated to the metastatic potential of HCC cells. After transfection with the PDCD4 gene, HCC cell proliferation rate was significantly decreased, cell apoptosis rate was significantly increased, the expression of MTA1 gene, HCC cell migration and Matrigel invasion were also remarkably inhibited.

CONCLUSION

PDCD4 expression is inversely correlated to the metastatic potential of HCC cells. PDCD4 can effectively suppress the metastatic potential of HCC cells.