Growth Capacity Of Cells Research Articles

In Vitro and In Vivo Antitumor Activity of Vitamin D3 in Malignant Gliomas: A Systematic Review

Context: The most common type of brain tumors are gliomas, among which glioblastoma multiforme is the most life-threatening. In spite of the existing treatments, malignant gliomas often do not respond to treatment. Objectives: The aim of this study was to investigate the antitumor activity of vitamin D3 in malignant gliomas through the study of in vitro and in vivo articles. Data Sources: The electronic databases, including PubMed, ScienceDirect, Web of Science, Google Scholar, and the Cochrane Central Register of Clinical Trials (last updated April 12th, 2019) were searched, using medical subject headings (MeSH) keywords “vitamin D AND brain malignancy”. Data Extraction: There was no limitation on the date and language of the articles. A review of all the found articles at the level of titles and abstracts was made to find eligible articles. Our work is in accordance with the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. The quality of the articles was judged in accordance with the GRADE tool for in vitro studies and CIRCLEs RoB tool for in vivo studies. Results: Totally, 88 articles were identified and after careful examination, 16 eligible articles meeting the inclusion criteria were selected. These studies showed that vitamin D3 and its analogs suppress self-renewal ability, cell viability and/or cell growth, migration rate, and invasive capacity; in addition, they induce autophagy and cell death. They also reduce tumor size in animal models. Evidence was mainly of moderate to high quality. Conclusions: Based on the in vitro and in vivo evidence of this systematic review, vitamin D3, compared to the control group, induced cell death and reduced cell growth, invasion, and migratory capacity in gliomas cell culture. As well as, vitamin D analogs were able to show the same effects without the hypercalcemic effect in vivo. We suggest performing future high-quality studies with the aim of shedding light on the relevant mechanisms and the effects of vitamin D3 derivatives and its analogs on health status and clinical outcomes in patients with malignant gliomas.

FAM83D promotes epithelial-mesenchymal transition, invasion and cisplatin resistance through regulating the AKT/mTOR pathway in non-small-cell lung cancer.

FAM83D has been proposed to act as an oncoprotein in several types of human cancer. Its role and mode of action in human non-small cell lung cancer (NSCLC) metastasis and its impact on chemotherapy are as yet, however, poorly understood. FAM83D expression was measured in NSCLC cells and normal lung epithelial cells, as well as in primary NSCLC tissues and corresponding adjacent non-cancerous tissues, using qRT-PCR, Western blotting and immunohistochemistry. FAM83D was stably overexpressed in BEAS2B cells or silenced in A549 and H1299 cells using retroviral or lentiviral vectors. The growth capacity of NSCLC cells was evaluated using MTT and colony formation assays. Epithelial-mesenchymal transition (EMT) was assessed using Western blotting and immunofluorescence. NSCLC cell invasive capacities were assessed using scratch wound healing and Boyden chamber assays. NSCLC cell viability in response to cisplatin treatment was assessed using MTT assays in vitro and a xenograft model in vivo. We found that FAM83D expression levels were significantly elevated in NSCLC cells and tissues, and positively correlated with tumor progression and a poor prognosis. Exogenous FAM83D overexpression promoted, while FAM83D silencing inhibited NSCLC cell proliferation, EMT and invasion. FAM83D silencing also reduced cisplatin resistance. Concordantly, we found that NSCLC patients with a low FAM83D expression benefited most from chemotherapy. Mechanistically, we found that FAM83D activated the protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway. Pharmacological treatment with either AKT or mTOR inhibitors reverted FAM83D-induced tumorigenic phenotypes. Our results suggest a role of FAM83D in NSCLC development. In addition, our resultsindicate that NSCLC patients exhibiting FAM83D overexpression are likely to benefit from AKT and/or mTOR inhibitor treatment.

MicroRNA-769-5p suppresses cell growth and migration via targeting NUSAP1 in bladder cancer.

BackgroundNucleolar and spindle‐associated protein 1 (NUSAP1) has been identified to be strongly implicated in the carcinogenesis of cervical carcinoma, breast cancer, and liver cancer, and shows a high expression level in bladder cancer, indicating that NUSAP1 might be a potent target for cancer treatment. Using bioinformatics methods, we found that NUSAP1 was a putative target of miR‐769‐5p. Here, we aimed to explore whether miR‐769‐5p is involved in bladder cancer progression via targeting NUSAP1.MethodsMiR‐769‐5p expression patterns in bladder cancer tissues and cells were detected by RT‐PCR. Kaplan‐Meier was used to determine the clinical effects of miR‐769‐5p expression levels on the overall survival of bladder cancer patients. Bioinformatics methods were used to predict the binding sites between miR‐769‐5p and NUSAP1, which was verified by the luciferase gene reporter assay. CCK‐8, flow cytometry, wound healing and transwell chamber experiments were performed to test cell growth, apoptosis, migration and invasion capacities.ResultsmiR‐769‐5p was lowly expressed in bladder cancer tissues and cells, which was closely associated with poor prognosis. Overexpression of miR‐769‐5p induced significant repressions in cell growth, migration, and invasion and caused an obvious increase in cell apoptosis, whereas these tendencies were reversed when NUSAP1 was upregulated.ConclusionThis study demonstrates that miR‐769‐5p functions as a tumor suppressor in bladder cancer via targeting NUSAP1.

Roles of MicroRNAs in Esophageal Squamous Cell Carcinoma Pathogenesis.

MicroRNAs (miRNAs) are 20-22 nucleotides long single-stranded noncoding RNAs. They regulate gene expression posttranscriptionally by base pairing with the complementary sequences in the 3'-untranslated region of their targeted mRNA. Aberrant expression of miRNAs leads to alterations in the expression of oncogenes and tumor suppressors, thereby affecting cellular growth, proliferation, apoptosis, motility, and invasion capacity of gastrointestinal cells, including cells of esophageal squamous cell carcinoma (ESCC). Thus, alterations in miRNAs expression associated with the pathogenesis and progression of ESCC. In addition, expression profiles of miRNAs correlated with various clinicopathological factors, including pathological stages, histological differentiation, invasion, metastasis of cancer, as well as survival rates and therapy response of patients with ESCC. Consequently, expression profiles of miRNAs could be useful as diagnostic, prognostic, and prediction biomarkers in ESCC. Herein, we describe the quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and microarray methods for detection and quantitate miRNAs in ESCC. In addition, we summarize the roles of miRNAs in ESCC pathogenesis, progression, and prognosis.

LncRNA Metastasis-Associated Lung Adenocarcinoma Transcript 1 Promotes Proliferation and Invasion of Non-Small Cell Lung Cancer Cells via Down-Regulating miR-202 Expression.

Objective Accumulating evidences indicate that long non-coding RNAs (lncRNAs) play key roles in cancer. This study aims to clarify role of the metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) in non-small cell lung cancer (NSCLC) and uncover the underlying mechanisms. Materials and Methods In this experimental study, MALAT1 and miR-202 expression in tissues and cell lines were detected using quantitative real time polymerase chain reaction (qRT-PCR) assay. Cell transfection was conducted using Lipofectamine 3000. Cell proliferation was determined with CCK-8 assay. MMP2 and MMP9 expressions were measured with Western blot. Cell invasive ability was evaluated by Transwell assay. Starbase 2.0 tool was used to predict targets of MALAT1. Dual luciferase reporter assay, RNA-binding protein immunoprecipitation assay and RNA pull-down assay were conducted to confirm the potential direct interaction between MALAT1 and miR-202. Results MALAT1 was overexpressed in NSCLC samples and cell lines. High expression of MALAT1 was related to large tumor size (>3 cm), poor histological grade, advanced cancer and tumor metastasis in NSCLC. In vitro assays exhibited that knockdown of MALAT1 remarkably decreased A549 cell growth and invasion capacity, while overexpression of MALAT1 significantly enhanced NCI-H292 cell proliferation and invasion ability. Next, we verified that MALAT1 could act as a competing endogenous RNA (ceRNA) by sponging miR-202 in NSCLC and there is a negative correlation between MALAT1 and miR-202. Besides, overexpression of miR-202 inhibited cell proliferation and invasive ability in MALAT1-overexpressed cells. ConclusionThis study demonstrated that lncRNA-MALAT1 gets involved in NSCLC progression by targeting miR- 202, indicating that MALAT1 may serve as a novel therapeutic target for NSCLC treatment.

Utility of starchy, lignocellulosics and cellulosics hydrolysates on cellulase production under liquid state fermentation

Starch is one of the most abundant renewable carbohydrate reserves of higher plants. It can be used to produce many valuable food products in the food processing industry. Furthermore, starch is also used as an important feedstock in the fermentation industry to produce value-added products. Lignocellulosic materials such as agriculture and forestry wastes are considered as a renewable feedstock for bioenergy production through a biochemical conversion process. Converting lignocellulosic biomass into fuels and chemicals entail a physicochemical pretreatment of the biomass, followed by enzymatic hydrolysis of the polysaccharide components such as cellulose and hemicellulose into monomeric sugars. These sugars can then be further fermented into other desired compounds of interest. During the deconstruction processes, various inhibitory compounds are released due to the partial over-degradation of lignocellulose biomass, which inhibits the cell growth and metabolic capacity of fermenting strains. Cellulosic materials such as waste paper in large quantities can also be used as potentially cheap feedstock for sustainable production of value-added products. The present investigation is mainly focused on the utility of starchy hydrolysates (wheat, potato, and rice) and lignocellulosics hydrolysates (bagasse and wheat straw) in cellulase production under liquid state fermentation. It also depicts the potential of cellulosic hydrolysate (waste newspaper) in product formation.

Long non-coding RNA FENDRR restrains the aggressiveness of CRC via regulating miR-18a-5p/ING4 axis.

There is increasing evidence has indicated that long non-coding RNAs (lncRNAs) are implicated in the tumorigenesis and development of colorectal cancer (CRC). Nevertheless, the clinical significances and functions of FENDRR in CRC remain unknown. In this study, we reveal that lncRNA FENDRR is downregulated in CRC and negatively correlated with advanced stage and poor clinical outcomes of patient with CRC. Overexpression of FENDRR represses the proliferation, migrate and invasive capacities of CRC cell in vitro, and upregulation of FENDRR inhibits the growth and distant metastatic capacity of CRC cell in vivo. Mechanistically, FENDRR interacts with miRNA-18a-5p (miR-18a-5p) and subsequently regulates the expression of inhibitor of growth 4 (ING4) in CRC cell. Interestingly, ING4 repression or miR-18a-5p rescues FENDRR induced proliferation and aggressive phenotypes inhibition of CRC cell. Altogether, our findings suggest that FENDRR exerts an inhibitory role in CRC by interacting with miR-18a-5p and future increases ING4 expression.

Proteomic analysis of thioproline misincorporation in Escherichia coli

Recently it was discovered that thioproline, an unnatural analog of proline, can arise in vivo from the reaction of cysteine and formaldehyde in cells under oxidative stress. Sequence-specific bioincorporation of thioproline into proteins was studied via shotgun proteomics of Escherichia coli (E. coli) cells. In a strain auxotrophic for proline, thioproline was found widely incorporated in lieu of proline when the cells were incubated with thioproline. In total 1428 proteins and 235 distinct thioproline-containing peptides were identified. Label-free relative quantitation revealed 102 differentially expressed proteins (82 up-regulated and 20 down-regulated) in the thioproline-treated group (with thioproline in the medium) relative to the control group (with proline in the culture medium). Pathway enrichment analysis of the differentially expressed proteins showed that amino acid biosynthesis and protein synthesis has been most affected by thioproline exposure, as expected. Phenotypically, the thioproline-treated group was found to exhibit slower cell growth and stronger antioxidant capacity relative to the control. SignificanceThioproline is a secondary metabolite of formaldehyde and a structural analog of proline. It is also known to exhibit a wide variety of pharmaceutical properties, but its exact biochemical role in the cell has not been elucidated. In this paper, we studied thioproline misincorporation (in lieu of proline) events during protein synthesis in E. coli. Global proteome profiling revealed that thioproline is extensively misincorporated throughout the proteome in E. coli cells exposed to thioproline, and pathways related to amino acid and protein biosynthesis are up-regulated. In addition, we demonstrated that pretreatment with thioproline appeared to increase E. coli cells' capacity to tolerate oxidative stress. Our findings suggest a novel explanation of thioproline's known antioxidative properties. This is, to our knowledge, the first ever study of thioproline misincorporation at the proteome level in any organism.

The splicing FK506-binding protein-51 isoform plays a role in glioblastoma resistance through programmed cell death ligand-1 expression regulation

Gliomas aberrantly express programmed cell death ligand-1 (PD-L1), which has a pivotal role in immunoevasion. The splicing isoform of FKBP5, termed FKBP51s, is a PD-L1 foldase, assisting the immune checkpoint molecule in maturation and expression on the plasma membrane. The concept that PD-L1 supports tumor-intrinsic properties is increasingly emerging. The aim of the present work was to confirm the pro-tumoral effect of PD-L1 on human glioma cell survival, stemness capacity and resistance, and to address the issue of whether, by targeting its foldase either chemically or by silencing, the aggressive tumor features could be attenuated. PD-L1-depleted glioma cells have a reduced threshold for apoptosis, while PD-L1 forced expression increases resistance. Similar results were obtained with FKBP51s modulation. The ability of PD-L1 to counteract cell death was hampered by FKBP51s silencing. PD-L1 expression was particularly high in glioma cells with a cancer-stem-cell profile. Moreover, PD-L1 sustained the spheroid formation capability of glioma cells. Targeting of FKBP51s by small-interfering RNA (siRNA) or the specific inhibitor SAFit2, reduced the number of formed spheroids, along with PD-L1 expression. Finally, in an orthotopic mouse model of glioblastoma, daily treatment with SAFit2 significantly reduced tumor PD-L1 expression, and tumor growth. In treated mice, caspase-3 activation and reduced vimentin expression were observed in excised tumors. In conclusion, targeting of FKBP51s hampers PD-L1 and its pro-tumoral properties, thereby affecting the self-renewal and growth capacities of glioblastoma cells in vitro and in vivo.

QKI-6 inhibits bladder cancer malignant behaviours through down-regulating E2F3 and NF-κB signalling.

Quaking homolog (QKI) is a member of the RNA‐binding signal transduction and activator of proteins family. Previous studies showed that QKI possesses the tumour suppressor activity in human cancers by interacting with the 3'‐untraslated region (3'‐UTR) of various gene transcripts via the STAR domain. This study first assessed the association of QKI‐6 expression with clinicopathological and survival data from bladder cancer patients and then investigated the underlying molecular mechanisms. Bladder cancer tissues (n = 223) were subjected to immunohistochemistry, and tumour cell lines and nude mice were used for different in vitro and in vivo assays following QKI‐6 overexpression or knockdown. QKI‐6 down‐regulation was associated with advanced tumour TNM stages and poor patient overall survival. QKI‐6 overexpression inhibited bladder cancer cell growth and invasion capacity, but induced tumour cell apoptosis and cell cycle arrest. Furthermore, ectopic expression of QKI‐6 reduced tumour xenograft growth and expression of proliferation markers, Ki67 and PCNA. However, knockdown of QKI‐6 expression had opposite effects in vitro and in vivo. QKI‐6 inhibited expression of E2 transcription factor 3 (E2F3) by directly binding to the E2F3 3'‐UTR, whereas E2F3 induced QKI‐6 transcription by binding to the QKI‐6 promoter in negative feedback mechanism. QKI‐6 expression also suppressed activity and expression of nuclear factor‐κB (NF‐κB) signalling proteins in vitro, implying a novel multilevel regulatory network downstream of QKI‐6. In conclusion, QKI‐6 down‐regulation contributes to bladder cancer development and progression.

Eckol inhibits Reg3A-induced proliferation of human SW1990 pancreatic cancer cells.

Pancreatic cancer (PaC) is characterized by a highly inflammatory tumor microenvironment, and inflammatory mediators are implicated in the progression of this cancer. Regenerating gene protein (Reg) 3A is significantly upregulated during pancreatic inflammation, and has been demonstrated to serve an important role during PaC progression, based on its increased expression levels in PaC and potent cell proliferation-promoting activity. The aim of the present study was to investigate the effect of eckol, a phlorotannin compound with a variety of biological activities including anti-inflammatory, anti-tumor and cytoprotective effects, on Reg3A-induced proliferation of human SW1990 PaC cells. SW1990 cells were pre-treated with eckol for 48 h at concentrations of 5, 10 and 20 µg/ml. Subsequently, Reg3A protein was added to the culture media at a final concentration of 50 ng/ml in the presence or absence of eckol for 24 h. The cytotoxicity and proliferative capacity of the SW1990 cells was determined using an MTT and flow cytometry analysis. Cell colony formation was also used to determine the effect of eckol on the anchorage-independent growth and colony-forming capacity of Reg3A-treated PaC cells. The expression levels of cyclin D1, STAT3, JAK2, and NF-κB p65 were measured with reverse transcription-quantitative PCR and western blotting. Eckol reduced Reg3A-promoted cell survival, inhibited Reg3A-induced cell cycle progression and inhibited colony growth of SW1990 cells in soft agar in a concentration-dependent manner. Additionally, the Reg3A-mediated upregulation of expression of JAK2, STAT3, NF-κBp65 and cyclin D1 was reduced when treated with eckol. Reg3A is upregulated during pancreatic inflammation and exhibits a pro-growth function and may thus serve a critical role during inflammation-driven PaC malignancies. Eckol may be a potential protective agent against progression of PaC accompanied by pancreatic inflammation.

Increased Smad3 and reduced Smad2 levels mediate the functional switch of TGF-β from growth suppressor to growth and metastasis promoter through TMEPAI/PMEPA1 in triple negative breast cancer.

Screening of several TNBC cell lines showed altered Smad2 and Smad3 protein levels compared to normal mammary epithelial cells, suggesting the possibility that it could play an important role in the escape of cancer cells from TGF-β mediated growth inhibition. To assess the functional relevance of these endogenous molecules, Smad2 or Smad3 expression was knocked down individually and assessed their effects on pro-oncogenic properties of TGF-β. Smad3 deficiency reduced growth and invasion capacity of breast cancer cells in comparison to Smad2 which had no effect. Smad3 deficiency was also found to be associated with a reduction in the expressions of TMEPAI/PMEPA1 and EMT inducing transcription factors, E-Cadherin and increased expression of cell cycle inhibitors and Vimentin. On the other hand, Smad2 deficiency had opposite effect on these regulators. Interestingly, the decreased growth, invasion and associated gene expressions were largely reversed by overexpressing TMEPAI in Smad3 knockdown cells, suggesting that Smad3-TMEPAI axis may be involved in subverting growth suppressive effects of TGF-β into growth promotion. Similarly, altered levels of Smad proteins and TMEPAI were also noted in primary TNBC tumor tissues. Analysis of the existing databases provided additional support in terms of TMEPAI and Smad2 expression impacting the survival of TNBC patients. Taken together, our data demonstrate a novel role for Smad3 in cancer transformation and cancer progression through TMEPAI and further suggest that selective targeting of TGF-β-Smad3-TMEPAI axis may be beneficial in triple negative breast cancer therapy and prevention.

Change in mutation frequency at a TP53 hotspot during culture of ENU-mutagenised human lymphoblastoid cells.

Mutations in oncogenes or tumour suppressor genes cause increases in cell growth capacity. In some cases, fully malignant cancer cells develop after additional mutations occur in initially mutated cells. In such instances, the risk of cancer would increase in response to growth of these initially mutated cells. To ascertain whether such a situation might occur in cultured cells, three independent cultures of human lymphoblastoid GM00130 cells were treated with N-ethyl-N-nitrosourea to induce mutations, and the cells were maintained for 12 weeks. Mutant frequencies and spectra of the cells at the MspI and HaeIII restriction sites located at codons 247-250 of the TP53 gene were examined. Mutant frequencies at both sites in the gene exhibited a declining trend during cell culture and reached background levels after 12 weeks; this was also supported by mutation spectra findings. These results indicate that the mutations detected under our assay conditions are disadvantageous to cell growth.

P3HT:Bebq2-Based Photovoltaic Device Enhances Differentiation of hiPSC-Derived Retinal Ganglion Cells.

Electric field stimulation is known to affect various cellular processes, including cell fate specification and differentiation, particularly towards neuronal lineages. This makes it a promising therapeutic strategy to stimulate regeneration of neuronal tissues. Retinal ganglion cells (RGCs) is a type of neural cells of the retina responsible for transduction of visual signals from the retina to the brain cortex, and is often degenerated in various blindness-causing retinal diseases. The organic photovoltaic materials such as poly-3-hexylthiophene (P3HT) can generate electric current upon illumination with light of the visible spectrum, and possesses several advantageous properties, including light weight, flexibility and high biocompatibility, which makes them a highly promising tool for electric stimulation of cells in vitro and in vivo. In this study, we tested the ability to generate photocurrent by several formulations of blend (bulk heterojunction) of P3HT (which is electron donor material) with several electron acceptor materials, including Alq3 and bis(10-hydroxybenzo[h]quinolinato)beryllium (Bebq2). We found that the photovoltaic device based on bulk heterojunction of P3HT with Bebq2 could generate photocurrent when illuminated by both green laser and visible spectrum light. We tested the growth and differentiation capacity of human induced pluripotent stem cells (hiPSC)-derived RGCs when grown in interface with such photostimulated device, and found that they were significantly increased. The application of P3HT:Bebq2-formulation of photovoltaic device has a great potential for developments in retinal transplantation, nerve repair and tissue engineering approaches of treatment of retinal degeneration.

Analysis of mesenchymal cells (MSCs) from bone marrow, synovial fluid and mesenteric, neck and tail adipose tissue sources from equines

Mesenchymal stem cells (MSCs) have been used in equines as an alternative therapy. A comparative study about the phenotype and in vitro performance of different MSCs tissue sources in adult equines was needed. This study might serve to provide the knowledge to select a valuable harvesting source of MSCs. Bone marrow, synovial and adipose (mesenteric, neck and tail fat) tissues were collected from adult equines.Cell surface markers expression (CD11α/CD18, CD45, CD79α, CD90, CD105 and MHC II) and in vitro differentiation assays were made. In vitro cell migration, cell growth and wound healing capacity tests helped to study their behavior and properties. MSCs phenotype was positively confirmed by the cell surfaces markers and a tri-lineage differentiation profile. Bone marrow cells showed the highest migration capacity, while synovial fluid cells displayed the highest cell growth. Bone marrow cells showed a better wound healing when compared with all the different MSCs. We conclude that bone marrow, synovial and adipose tissue derived from adult equines are a good source for cell therapy but they conserve different functional properties: bone marrow showed an interesting migration and wound healing capacity while synovial fluid cells and their highest cell growth suggest that these MSCs would yield higher cell numbers in a shorter time.

In vitro differentiation of mouse T cell-derived hybrid cells obtained through cell fusion with embryonic stem cells

Nuclear reprogramming is an innovative advance in cell biology. An important research initiative in this field is cell fusion-mediated nuclear reprogramming, wherein the nuclei of somatic cells, such as thymocytes, are initialized through cell fusion with embryonic stem cells (ESCs). However, hybrid cells obtained through cell fusion between ESCs and thymocytes failed to contribute to the embryo proper when injected into blastocysts, which suggested that there are fundamental defects in such hybrid cells. Here, we performed side-by-side comparative analyses of the in vitro growth and differentiation capacities of ESCs and ESC-T hybrid cells. We found that the hybrid cells were larger and proliferated more slowly than the ESCs in 2i/LIF medium. Upon in vitro induction of differentiation, hybrid cells gave rise to cells of the three germ layers. Under culture conditions for hematopoietic differentiation, hybrid cells successively differentiated into lateral mesodermal cells, hemogenic endothelial cells, and various types of hematopoietic cells, including erythroid, myeloid, and lymphoid cells, although T cell maturation in the CD4/CD8 double-negative fraction was delayed. These results verified the multi-lineage differentiation capacity of ESC-T hybrid cells. The minimal contribution of hybrid cells to chimeric embryos may be due to their slow growth.

Down-regulation of FZD3 receptor suppresses growth and metastasis of human melanoma independently of canonical WNT signaling

Frizzled 3 receptor (FZD3) plays an important role in the homeostasis of the neural crest and its derivatives, which give rise to pigment-synthesizing cells, melanocytes. While the role for FZD3 in specification of the melanocytic lineage from neural crest is well established, its significance in the formation of melanoma, its associated malignancy, is less understood. In this study we identified FZD3 as a critical regulator of human melanoma tumorigenesis. Down-regulation of FZD3 abrogated growth, colony-forming potential, and invasive capacity of patient-derived melanoma cells. Xenotransplantation of tumor cells with down-regulated FZD3 levels originating from melanomas carrying the BRAF(V600) mutation uniformly suppressed their capacity for tumor and metastasis formation. FZD3 knockdown leads to the down-regulation of the core cell cycle protein components (cyclins D1, E2, B1, and CDKs 1, 2, and 4) in melanomas with a hyperactive BRAF oncogene, indicating a dominant role of this receptor during melanoma pathogenesis. Enriched pathway analysis revealed that FZD3 inhibits transcriptional networks controlled by CREB5, FOXD1, and ATF3, which suppress the activity of MAPK-mediated signaling. Thus, FZD3 establishes a positive-feedback mechanism that activates MAPK signal transduction network, critical to melanoma carcinogenesis. Importantly, high levels of FZD3 mRNA were found to be correlated with melanoma advancement to metastatic stages and limited patient survival. Changes in gene-expression patterns mediated by FZD3 activity occur in the absence of nuclear β-catenin function, thus representing an important therapeutic target for the melanoma patients whose disease progresses independent of canonical WNT signaling.

Expression of PDK1 in malignant pheochromocytoma as a new promising potential therapeutic target

Phosphoinositide-dependent kinase 1 (PDK1) is highly expressed in many solid tumors. And several studies have demonstrated that PDK1 has been an emerging and promising target for anti-cancer therapies. However, the role of PDK1 has not been studied so far in malignant pheochromocytoma (PCC). In this study, immunohistochemical staining was performed to investigate the protein level of PDK1 in 63 PCC tissue samples, of which 49 were benign and 14 were malignant. In addition, we evaluated the effect of inhibition of PDK1 with siRNA on cell growth, apoptosis and invasive capacity in PC12 cells and identified the underlying mechanisms. We found that PDK1 was overexpressed in malignant PCC tissues, and knockdown of PDK1 with siRNA significantly inhibited cell proliferation, increased apoptosis induction, and attenuated cell migration and invasive capacity in PC12 cells. We also showed that knockdown of PDK1 significantly reduced the phosphorylation of Akt at threonine 308 (p-Akt T308) but did not alter the serine phosphorylation of Akt on the S473 site (p-Akt S473). Furthermore, we found that the p-Akt expression was noticeably decreased after knockdown of PDK1, but the t-Akt expression did not show a significant decrease. We have demonstrated for the first time that PDK1 is overexpressed in human malignant PCC and plays an important role in the malignant biological behaviors of PC12 cell. Specifically, we have revealed that knockdown of PDK1 could attenuate activation of the Akt signaling. These data suggest that PDK1 could be a new promising potential therapeutic target in human cancer treatment for malignant PCC.

Chromatin accessibility changes are associated with enhanced growth and liver metastasis capacity of acid-adapted colorectal cancer cells

ABSTRACT The acidic extracellular microenvironment, namely acidosis, is a biochemical hallmark of solid tumors. However, the tumorigenicity, metastatic potential, gene expression profile and chromatin accessibility of acidosis-adapted colorectal cancer cells remain unknown. The colorectal cancer cell SW620 was cultured in acidic medium (pH 6.5) for more than 3 months to be acidosis-adapted (SW620-AA). In comparison to parental cells, SW620-AA cells exhibit enhanced tumorigenicity and liver metastatic potential in vivo. Following mRNA and lncRNA expression profiling, we validated that OLMF1, NFIB, SMAD9, DGKB are upregulated, while SESN2, MAP1B, UTRN, PCDH19, IL18, LMO2, CNKSR3, GXYLT2 are downregulated in SW620-AA cells. The differentially expressed mRNAs were significantly enriched in DNA remodeling-associated pathways including HDACs deacetylate histones, SIRT1 pathway, DNA methylation, DNA bending complex, and RNA polymerase 1 chain elongation. Finally, chromatin accessibility evaluation by ATAC-sequencing revealed that the differentially opened peaks were enriched in pathways such as small cell lung cancer, pathways in cancer, ErbB signaling, endometrial cancer, and chronic myeloid leukemia, which were mainly distributed in intergenic regions and introns. These results suggest that the chromatin accessibility changes are correlated with enhanced growth and liver metastasis capacity of acid-adapted colorectal cancer cells.

Metformin Inhibit Lung Cancer Cell Growth and Invasion in Vitro as Well as Tumor Formation in Vivo Partially by Activating PP2A.

BackgroundThe aim of this study was to investigate whether PP2A activation is involved in the anti-cancer activity of metformin.Material/MethodsA549 and H1651 human lung cancer cells were constructed with stable α4 overexpression (O/E α4) or knockdown of PP2A catalytic subunit A/B(sh-PP2Ac). Influences of okadaic acid (OA) treatment, O/E α4 or sh-PP2Ac on metformin treated cells were investigated by cell viability, proliferation, apoptosis, and Transwell invasion assay in vitro. Protein expression levels of Bax, Bcl-2, Myc, and Akt as well as serine phosphorylation level of Bax, Myc, and Akt were examined by western blot. For in vivo assays, wild type (WT) or modified A549 cells were subcutaneously injected in nude mice, and metformin treatment on these xenografted tumors were assayed by tumor formation assay and western blot detecting cell proliferation marker PCNA (proliferating cell nuclear antigen) as well as protein expression level and serine phosphorylation level of Akt and Myc.ResultsMetformin treatment significantly reduced A549 or H1651 cell growth and invasive capacity in vitro as well as Ser184 phosphorylation of Bax, Ser62 phosphorylation of Myc, and Ser473 phosphorylation of Akt, all of which could be partially attenuated by OA treatment, O/E α4 or sh-PP2Ac. Metformin treatment also significantly reduced tumor formation in vivo as well as protein expression of PCNA, Akt, Myc, and serine phosphorylation of the latter 2, which can be partially blocked by O/E α4 or sh-PP2Ac.ConclusionsMetformin reduced lung cancer cell growth and invasion in vitro as well as tumor formation in vivo partially by activating PP2A.