Survivin Gene Expression Research Articles

Ki-67 pulmonary immunoreactivity in silver nanoparticles toxicity: Size-rate dependent genotoxic impact

Engineered nanoparticles have been recently utilized in numerous domains particularly, silver nanoparticles (AgNPs). Nonetheless, the possible side effects resulting from AgNPs exposure are not fully clarified. The present study was designed to clarify the toxicity of AgNPs on lung tissue. Furthermore, therapeutic impact of Glycosmis pentaphylla (G. pentaphylla) and Casimiroa edulis (C. edulis) leaves extracts in addition to mucilage and protein (the purified compounds from C. edulis) was investigated against AgNPs induced pulmonary toxicity. Male Swiss albino mice were administered AgNPs orally in two different particle sizes (20 nm and 100 nm) for one month and was further treated via G. pentaphylla, C. edulis, mucilage and protein in a dose of 500 mg/ kg for three weeks. Biochemical, molecular, immunohistochemistry, and histopathological investigations were further assessed. An obvious alteration in oxidative stress biomarkers as well as mRNA gene expression of both survivin and matrix metalloproteinase (MMP-9) was recorded in AgNPs intoxicated group. In addition to, exploration of positive nuclei for Ki-67 was also observed upon AgNPs intoxication. Data declared a significant improvement in the assessed parameters upon G. pentaphylla, C. edulis, mucilage and protein treatment. In conclusion; G. pentaphylla and C. edulis extracts could be considered as a promising candidate as therapeutic regimen against pulmonary toxicity induced via AgNPs due to their enrichment with different active constituents. Practical applicationsDue to the expansion of AgNPs applications, it is urgent to investigate their toxic impact associated with release of free silver ions. Different particle sizes of AgNPs can induce various alterations in cellular biochemical parameters, mRNA gene expression, histopathological and immunohistopathological examination. Herein, this natural products extracts are used for the first time as promising therapeutic regimen to ameliorate the toxic effect in AgNPs intoxicated lung tissue in mice model as a result of the bioactive metabolites, especially flavonoids and polyphenolic compounds.

Effects of Staphylococcus aureus enterotoxin type A on inducing the apoptosis in cervical cancer cell line

Recently, a number of studies have revealed that biotoxins present great potential as antitumor agents, such as some bacteria toxins, so they could be used as chemotherapeutic agents against tumors. In this study, the effects of Staphylococcus aureus enterotoxin type A on BAK, FAS, BAX, TNF-α, p53, BCL-2 and Survivin genes expression in HeLa cell lines were investigated. These cells are transfected with the pcDNA3.1(+)-sea (recombinant) and pcDNA3.1(+) (non-recombinant) plasmids. The expression of BAK, FAS, BAX, TNF-α, p53, BCL-2 and Survivin genes in transfected cells were then analyzed by real time PCR. The results showed an increase in the expression of BAK, FAS, BAX, TNF-α and p53 genes and decreased BCL-2 and Survivin expression at a significant level. As compared to the HeLa cell, which did not receive the sea gene, the cells containing the toxin gene had progressed more towards apoptosis. Staphylococcal enterotoxin type A has an inhibitory effect on the growth, proliferation and invasion of breast and cervical cancerous cells through altering the expression of the genes involved in the apoptosis process. Therefore, it seems that there is a good research field for the use of this toxin in the control and treatment of such malignancies.

Biodegradable mesoporous manganese carbonate nanocomposites for LED light-driven cancer therapy via enhancing photodynamic therapy and attenuating survivin expression

Triple-negative breast cancer (TNBC) is one of the most daunting diseases, low toxicity and efficient approaches are in urgent demand. Herein, we developed degradable mesoporous manganese carbonate nanocubes (MnCO3 NCs), incorporated with survivin shRNA-expressing plasmid DNA (iSur-pDNA) and riboflavin (Rf), namely MRp NCs, for synergistic TNBC therapy. The MnCO3, itself, could generate O2 and CO2 under H2O2 and thus relieve the hypoxia and acidic tumor microenvironment (TME). Furthermore, the MnCO3 NCs exhibited high Rf loading capacity and iSur-pDNA delivery ability after polyethyleneimine modification. Specifically, MRp NCs decompose in TME, meanwhile they deprived the endogenous expression of survivin gene and significantly amplified the generation of reactive oxygen species after exposure to LED light, resulting in serious tumor destruction. The multifunctional MRp NCs with LED light-driven characters are able to provide a high efficiency, low toxicity and promising strategy for TNBC therapy.

Lipofection of Single Guide RNA Targeting MMP8 Decreases Proliferation and Migration in Lung Adenocarcinoma Cells.

Background and Objectives: Matrix metalloproteinases (MMP) have been implicated as major determinants of tumour growth and metastasis, which are considered two of the main hallmarks of cancer. The interaction of MMP8 and other signalling molecules within and adjacent tumoral tissues, including immune cells, are rather elusive, particularly of adenocarcinoma cell type. In this study, we aimed to investigate the role of MMP8 in non-small cell lung cancer proliferation and invasiveness potential. Materials and Methods: We individually lipofected with two different single guide RNA (sgRNAs) that specifically targeted on MMP8, with CRISPR-Cas 9 protein into the cells. Results: Our results clearly indicated that the lipofection of these complexes could lead to reduced ability of A549 cells to survive and proliferate to form colonies. In addition, when compared to non-transfected cells, the experimental cell groups receiving sgRNAs demonstrated relatively decreased migration rate, hence, wider wound gaps in scratch assay. The quantitative real time-polymerase chain reaction (qRT-PCR) demonstrated significant reduction in the MAP-K, survivin and PI3-K gene expression. MMP8 might have protective roles over tumour growth and spread in our body. Conclusions: The delivery of sgRNAs targeting on the MMP8 gene could induce tumour cell death and arrest cell migratory activity.

Lung development, repair and cancer: A study on the role of MMP20 gene in adenocarcinoma.

Multiple matrix metalloproteinases have significant roles in tissue organization during lung development, and repair. Imbalance of proteinases may lead to chronic inflammation, changes in tissue structure, and are also highly associated to cancer development. The role of MMP20 is not well studied in lung organogenesis, however, it was previously shown to be present at high level in lung adenocarcinoma. The current study aimed to identify the functional properties of MMP20 on cell proliferation and motility in a lung adenocarcinoma in vitro cell model, and relate the interaction of MMP20 with other molecular signalling pathways in the lung cells after gaining tumoral properties. In this study, two different single guide RNA (sgRNAs) that specifically targeted on MMP20 sites were transfected into human lung adenocarcinoma A549 cells by using CRISPR-Cas method. Following that, the changes of PI3-K, survivin, and MAP-K mRNA gene expression were determined by Real-Time Polymerase Chain Reaction (RT-PCR). The occurrence of cell death was also examined by Acridine Orange/Propidium Iodide double staining. Meanwhile, the motility of the transfected cells was evaluated by wound healing assay. All the data were compared with non-transfected cells as a control group. Our results demonstrated that the transfection of the individual sgRNAs significantly disrupted the proliferation of the A549 cell line through suppression in the gene expression of PI3-K, survivin, and MAP-K. When compared to non-transfected cells, both experimental cell groups showed reduction in the migration rate, as reflected by the wider gaps in the wound healing assay. The current study provided preliminary evidence that MMP20 could have regulatory role on stemness and proliferative genes in the lung tissues and affect the cell motility. It also supports the notion that targeting MMP20 could be a potential treatment mode for halting cancer progression.

Ursolic acid disturbs ROS homeostasis and regulates survival-associated gene expression to induce apoptosis in intestinal cancer cells.

Ursolic acid is a natural compound possessing several therapeutic properties including anticancer potential. In present study, cytotoxic and antimetastatic properties of ursolic acid were investigated in intestinal cancer cell lines INT-407 and HCT-116. The cells growth and number were decreased in a dose- and time-dependent manner in both the cell lines. It also increases reactive oxygen species levels in the cells in order to induce apoptosis. Ursolic acid was found to be a significant inhibitor of cancer cells migration and gene expression of migration markers FN1, CDH2, CTNNB1 and TWIST was also downregulated. Ursolic acid treatment downregulated the gene expression of survival factors BCL-2, SURVIVIN, NFKB and SP1, while upregulated the growth-restricting genes BAX, P21 and P53. These results indicate that ursolic acid has anticancer and antimetastatic properties against intestinal cancer. These properties could be beneficial in cancer treatment and could be used as complementary medicine.

Hepatoprotective Effects of Chitosan on Thioacetamide-Induced Liver Toxicity in Male Albino Rats

Chitosan, a natural product derived from chitin, has attracted much attention as a promising polysaccharide compound, owing to its unique biological activities. This study was designed to explore the possible improving potential of chitosan, as a natural marine product, on liver regeneration in hepatotoxicity induced by thioacetamide in male albino rats. Fifty animals were divided into 5 groups, including the control group; a group which was injected intraperitoneally with a single dose of thioacetamide(300 mg/kg b. wt) for induction of liver toxicity; a group received a diet containing 5% chitosan for 14 days; a group received a diet containing 5% chitosan for 14 days then they were injected with thioacetamide(300 mg/kg b. wt) once, and the last group which was injected with thioacetamide(300 mg/kg b. wt) once then received a diet containing 5% chitosan for 14 days. The biochemical results revealed that the intake of chitosan before or after thioacetamide intoxication improved liver markers (ALAT, ASAT, GGT, ALP, albumin) and kidney functions and also plasma TNF-α. QRT- PCR analysis revealed that chitosan downregulated hepatic TNF-α, survivin, and c-Myc quantitative gene expression. Moreover, chitosan improved the histological picture of the liver. This study indicated the promising action of chitosan in liver regeneration.

THE CORRELATION OF THE BRCA-IRIS GENE EXPRESSION AND BIOMARKER GENES IN BREAST CANCER PATIENTS: CORRELATION WITH TUMOR PROGRESSION AND RESPONSE TO TREATMENT

Background: Triple-negative breast cancer (TNBC) is an aggressive phenotype with bad prognosis and poor survival. The prognostic and predictive values of BRCA1-Iris, octamer-binding transcription factor 4 (oct 4), cyclin D1andsurvivin were assessed in TNBC patients compared with N-TNBC patients. Method: RNA expression levels of BRCA1-IRIS, Oct4, Cyclin D1 and Survivin gene were tested in for 100 breast cancer patients by qRT-PCR. Result: overexpression ofBRCA1-IRIS RNA was found in 49 % of breast cancer patients [(35(71 %) of TNBC cases vs 14(28.6% of N-TNBC] (p < 0.001). There was significantly correlated between the BRCA1-IRIS and tumor stage, ER and PR (p=0.036, p < 0.001 and p=0.006; respectively) in breast cancer patients. In TNBC or N-TNBC, no statistically significance between BRCA1-IRIS and any clinicopathological features of patients. There was significant association between BRCA1-IRIS positive and the expression of oct4, cyclin D1 and survivin gene in TNBC patients (p < 0.001, p=0.001 and p=0.002; respectively). There was a strong significant correlation between the expression of oct4 and the BRCA1-IRIS negative (p < 0.001) in TNBC group. No significant association between BRCA1-IRISpositive in N-TNBC and any of the gene expression. BRCA1-IRISnegative was correlated significantly with oct4 and cyclin D1expression (p=0.001each).No significant correlation between the expression RNA level of oct4, cyclin D1 and survivin gene and the expression RNA level of BRCA1-IRIS except lymphnode with survivin gene expression (p=0.05). No significant relation between the expression level of oct4, cyclin D1 and survivin gene and the relevant clinicopathological features with or without BRCA1-IRIS expression. Expression level of survivin and cyclin D1 was significantly correlation with the response to treatment (p=0.001 and p < 0.001). No significant different between overall survival and BRCA1-IRIS expression (p=0.291 long rang). However, disease-free survival was increased in BRCA1-IRIS positive cases (p = 0.052 long rang)

THE RNA EXPRESSION LEVEL OF SURVIVIN, OCT 4 AND CYCLIN D1 GENES IN TRIPLE NEGATIVE AND NON-TRIPLE NEGATIVE BREAST CANCER

Background: the purpose of the present study to investigate the RNA expression level of Oct4, Survivin and Cyclin D1 genes in Triple-negative breast cancer (TNBC) and compared to non-triple negative breast cancer (non-TNBC) group. Also, correlate the results of gene expression with clinicopathological features of patients. Method, RNA expression levels of Oct4, Survivin and Cyclin D1 was tested for 100 breast cancer (BC) patients [formalin fixed paraffin embedded tissue (FFPE)] diagnosed as invasive duct carcinoma in Pathology Department, National Cancer Institute (NCI), Cairo University. The qRT-PCR technique is use and the results correlated to clinico-pathological characteristics of patients and survival rates. Result, in (TNBC) patients, oct4, survivin and cyclin D1 showed positive expression in 30 (60%), 32(64%) and 32 (64%) (p < 0.001, p= 0.001 and p= 0.003;respectively). In non-TNBC patients, the positive expression of oct4, survivin and cyclin D1 gene was 11(22%), 15(30%) and 17(34%) (p < 0.001, p= 0.001 and p= 0.003;respectively). All patients in TNBC have negative ER, PR and HER-2 receptor (p=0.001). There was highly statistically significant difference between oct4 gene expression and all the clinico-pathological features except the family history. A significant difference between cyclin D1gene expression and all the clinico-pathological features except the tumor size, tumor grade and lymphnode status. Statistically difference was found between survivin gene expression and all the clinico-pathological features except the menopause state, tumor stage and tumor grade. Triple negative breast cancer patients showed significantly decreased DFS (p < 0.001, log rank) and OS (p= 0.002, log rank) when compared to those with non-TNBC patients. In TNBC group, patients with positive expression of survivin was significantly associated with decreased OS (p= 0.03, log rank). TNBC tumors with positive oct4 and cyclin D1 had reduced OS compared to those negative to oct4 and cyclin D1 but without significant difference (p= 0.8 and p= 0.09, respectively, log rank). In non-TNBC group, with positive oct4, cyclin D1 and survivin did not significantly differ in terms of DFS and OS when compared to those with negative expression. Conclusion: Oct4 and survivin expression gene are better marker used for diagnosis in TNBC and for molecular targeting therapy of TNBC treatment. Cyclin D1 expression used as a marker for aggressive TNBC. The TNBC tumor possibly respond to treatment that downregulates cyclin D1 amplifica tion. More studied and large sample size is needed.

Ethyl acetate extract of Clausena excavata induces growth inhibition of non-small-lung cancer, NCI-H460, cell line via apoptosis.

Clausena excavata Burm. f is a plant used in folklore medicine for the treatment of various ailments in South East Asia. The plant parts contain chemical components that are cytotoxic to many cancer cells. The study investigated the cytotoxic effects of ethyl acetate, methanol and chloroform C. excavata leaf extracts on the non-small-lung cancer, NCI-H460, cell line. Based on the 3-(4,5-dimethylthiazol-2-yl)-2,5,-diphenyltetrazolium bromide (MTT) assay, among extracts, ethyl acetate C. excavata leaf extract (EACE) was the most potent anti-NCI-H460 cells, with IC50 value of 47.1 ± 6.1 μg/ml. The effects of EACE on NCI-H460 cells were also determined by clonogenic, 4', 6-diamidino-2-phenylindole (DAPI), and annexin-V-fluorescein isothiocyanate/propidium iodide-PI flow cytometric assays. Reactive oxygen species (ROS) production and apoptotic gene expressions was determined via flow cytometry and real-time quantitative PCR, respectively. EACE-treated NCI-H460 cells after 48 h underwent apoptosis as evident by loss of cell viability, cell shrinkage, and chromatin condensation. The results also showed EACE mediated increase in ROS production by the NCI-H460 cells. After 48 h treatment, EACE increased the pro-apoptotic BAX and decreased the anti-apoptotic Bcl-2, Survivin and c-Myc gene expressions. EACE is a potential anti-lung cancer by increasing cancer cell ROS production and apoptosis.

Effect of Feed Withdrawal Stress on Reproductive Tissue, Sex Steroids and mRNA Expression of IGF-1, Survivin, Caspase 2 and HSP 70 Gene in the Ovarian Follicles of Japanese Quail

Background: Japanese quail, similar to domestic chicken, is equally sensitive and susceptible to stress but limited literatures are available so far. Therefore, this study was aimed to investigate the effect of feed withdrawal stress on the changes in reproductive tissues, steroid hormones and gene expression in Japanese quail. Methods: Forty two quail hens (10weeks) were individually caged and subjected to feed withdrawal for a period of 10 days without water restriction. Six birds each were sacrificed on 0, 1, 2, 4, 6, 8 and 10 day. The reduction in oviduct weight and serum concentration of steroid hormones was evaluated. The quantitative expression of IGF-1, Caspase-2, Survivin and HSP-70 genes were performed in ovarian follicles using real-time PCR. Result: No hierarchial follicles were detected after day 6. The ovary and oviduct weight was significantly reduced on day 2 and 4 respectively. The serum estrogen and progesterone were declined significantly when corticosterone was increased from day 1. The IGF-1 gene expression was significantly (P less than 0.05) down regulated in yellow and atretic follicles. The gene expression of Survivin and caspase-2 was up-regulated in F3 follicle. It concludes feed withdrawal brings noticeable change in reproductive tissues, steroid hormones and associated gene expression in Japanese quail.

Evaluation of potential tumor markers that may predict neoadjuvant treatment efficiency in rectal cancer

Abstract Objectives The recurrence of rectal cancer or its resistance to neoadjuvant treatment develops due to the adaptation to hypoxia, apoptosis or autophagy. Survivin, one of the inhibitors of apoptosis; Beclin 1, which is a positive regulator in the autophagy pathway; and hypoxia-inducible factor-1α (HIF-1α) and carbonic anhydrase-9 (CA9), which are associated with tumor tissue hypoxia, may be related to resistance to treatment. Our aim was to evaluate the potential tumor markers that may help to monitor the response to neoadjuvant treatment in locally advanced rectal cancer (RC). Methods Twenty-five patients with locally advanced RC were included in the study. Gene expression and protein levels of Beclin 1, Survivin, HIF-1α, and CA9 were analyzed in fresh tissue specimens and blood samples. The relationships of these markers to tumor staging and regression grade were evaluated. Results Higher blood CA9 gene expression levels and lower blood HIF-1α protein levels were found in the response group according to tumor regression grade. After neoadjuvant treatment, tissue Beclin 1 and blood Survivin gene expressions and tissue CA9, blood Beclin 1 and blood HIF-1α protein levels decreased significantly. Conclusion Beclin 1, Survivin, HIF-1α ve CA9 may help to predict the effects of the applied treatment approach.

Apoptotic Effects of Bilirubin on Skin Cancer Cell Lines SK-MEL-3 (Melanoma) and A431 (Non-Melanoma).

Bilirubin has long been exclusively considered as a potentially dangerous sign of liver diseases, but it is currently regarded as a reliable signaling molecule as well. This study investigated the effects of unconjugated bilirubin on survival, proliferation, apoptotic and cell arrest capacities of melanoma SKMEL-3 and non-melanoma A431 skin cancer cells in comparison with normal Human Dermal Fibroblast (HDF) cells. The MTT assay test was used to identify survival and the IC50 at various concentrations of bilirubin on SKMEL-3, A431, and HDF cells for 24h and 48h. The comet assay technique was used to investigate genotoxicity effects, and flow cytometry was run to investigate apoptotic and cell arresting effects of bilirubin on the cells. The gene expression of cyclin D1, cyclin E1, survivin, Bcl-2, and p53 was investigated by qRT-PCR. The molecular docking of bilirubin on CDKs (Cyclin-Dependent Kinases 2, 4, and 6) and pro-apoptotic factors Bad, Bak, Bax, Bid, Bik, and Bim was performed by Autodock software version 2. The IC50 of bilirubin on HDF, A431, and SKMEL-3 cells was 125, 115, and 95 μM at 24h and 115, 100, and 75 μM at 48h, respectively. Although cell arrest in the G1 phase occurred in all cells, bilirubin induced genotoxicity and apoptosis in SKMEL-3 and A431 cancer cells more pronouncedly than those in normal HDF cells. Bilirubin led to cell arrest in the G1 phase in SKMEL-3, A431, and HDF cells. Additionally, bilirubin induced apoptotic pathways in SKMEL-3 and A431 cancer cells.

Probiotic Saccharomyces cerevisiae var. boulardii supernatant inhibits survivin gene expression and induces apoptosis in human gastric cancer cells.

Natural anticancer drug and compounds with other great benefits are of interest recently due to lower side effects than chemotherapy for cancer treatment and prevention. Different natural and synthetic drugs have been suggested to be used for treatment of gastric cancers, the second deadly cancer worldwide. The aim of this study was to investigate anticancer activity of SBS including inducing apoptosis and inhibition of survivin gene expression in gastric cancer cells. We evaluated cell viability, inducing apoptosis and change in survivin gene expression of EPG85‐257P (EPG) and EPG85‐257RDB (resistant to Daunorubicin, RDB) cell lines under exposure of SBS after 24, 48, and 72 hr. We found that SBS decreased cell viability, induced apoptosis, and reduced survivin gene expression in treated EPG and RDB cells (with the significant IC50 values of 387 and 575 µg/ml after 72 and 48 hr for EPG and RDB cells respectively). However, we observed SBS was more efficient to induce apoptosis in EPG than RDB cells. We strongly suggest SBS be considered as a prospective anticancer agent or in formulation of complementary medication to treat and prevent gastric cancers.

Expression of survivin and p53 genes in patients with alopecia areata: A case-control study.

Alopecia areata is a common non-scarring hair loss disorder. It has been generally recognised as a loss of immune privilege leading to an autoimmune attack upon anagen hair follicles. Survivin is one of the apoptosis inhibitor proteins, responsible for apoptosis suppression and cell cycle regulation. Survivin expression has been demonstrated in the matrix and outer root sheath keratinocytes of anagen hair follicles. Survivin overexpression was shown in several autoimmune diseases, and it was postulated that it contributes to the survival of self-reactive T and B cells. P53 is a tumour suppressor gene that was suggested to repress autoimmunity via induction of T regulatory cells. Survivin gene expression is transcriptionally suppressed by wild-type p53. The aim of this study was to investigate survivin and p53 genes expression in alopecia areata patients. The mRNA tissue expression of survivin and p53 was measured by quantitative real-time polymerase chain reaction in lesional and non-lesional punch scalp biopsies of 25 alopecia areata patients and 25 healthy subjects. The study showed higher mRNA expression of survivin in lesional biopsies compared to non-lesional (P<0.001) and control biopsies (P=0.001). In non-lesional biopsies, the expression was significantly lower than in control biopsies (P<0.001). The expression of p53 was lower in both lesional and non-lesional biopsies relative to control biopsies. However, the difference was only significant in non-lesional biopsies (P=0.017). Our results suggested that survivin and p53 genes expression was altered in patients with alopecia areata.

YM155 Reverses Cabazitaxel Resistance in Castration-resistant Prostate Cancer by Reducing Survivin Expression.

The purpose of the present study was to clarify whether treatment with YM155, a novel small-molecule inhibitor of survivin, reversed cabazitaxel resistance in castration-resistant prostate cancer (CRPC). Cabazitaxel resistance was induced in the castration-resistant prostate cancer cell line, 22Rv1-CR. In vitro and in vivo models were used to test the efficacy of YM155 and cabazitaxel. Survivin gene expression was significantly higher in 22Rv1-CR than its parent cells (22Rv1). In 22Rv1-CR cells, YM155 significantly reduced expression of the survivin gene in a concentration-dependent manner. YM155 alone was poorly effective; however, it significantly enhanced the anticancer effects of cabazitaxel on 22Rv1-CR in vitro and in vivo. Inhibition of survivin by YM155 overcomes cabazitaxel resistance in CRPC cells.

Development of a carrier system containing hyaluronic acid and protamine for siRNA delivery in the treatment of melanoma.

The use of small interfering RNA (siRNA) in melanoma treatment remains limited owing to its biological properties. Herein, we developed a carrier system containing hyaluronic acid and protamine for siRNA delivery. Considering zeta potential and particle size as standards, the ratio of each component in liposome nanoparticles prepared was screened using the control variable method, and siRNA cationic liposome nanoparticles were prepared based on the optimal results obtained. The encapsulation rate of the cationic liposome nanoparticles was measured, and particle morphology was observed. B16F10 cells were treated with the nanoparticles; 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay, cell scratch experiments, and cell uptake experiments were performed to determine the effectiveness of the loaded siRNA. A mouse model was then established, and tumour tissues were subjected to haematoxylin-eosin staining. The inhibition of the survivin gene and protein expression were assessed using reverse transcription-polymerase chain reaction and western blotting, respectively. The results showed that the optimal mass ratio of hyaluronic acid (HA)-siRNA-to-protamine was 1.0; in the HA-siRNA-protamine complex containing 25μg siRNA, the addition of 50μL liposomes yielded optimal particles. And encapsulation rate was 85.07%. The nanoparticles demonstrated a significant inhibitory effect against melanoma cells; siRNA liposomes may inhibit tumour growth by down-regulating survivin. Survivin-siRNA cationic liposome nanoparticles could effectively inhibit the proliferation and migration of melanoma B16F10 cells in vitro and the proliferation of subcutaneous melanoma B16F10 cells, probably by inhibiting survivin mRNA and protein expression. Graphical abstract.

Evaluation of E2F3 and survivin expression in peripheral blood as potential diagnostic markers of prostate cancer

Abstract Background Prostate cancer (PC) incidence has risen globally. As there are no current independent biomarkers with high diagnostic efficiency to detect PC, this study was performed to investigate the relative gene expression levels of E2F3 and survivin in the whole blood of PC, benign prostate hyperplasia (BPH), and normal control individuals and to explore their diagnostic value. Material and methods Participants of the study were divided into three groups; normal control group (n=25), BPH patients (n=25), and PC patients (n=75). The E2F3 and survivin gene expression levels were assessed using real-time qPCR in addition to the measurement of free and total levels of prostate-specific antigen (PSA) using electrochemiluminescence assays. Results Survivin relative gene expression was over-expressed in PC and BPH patients compared to the normal control group, whereas, E2F3 did not differ significantly among the studied groups. Compared to PSA, E2F3 and survivin mRNA expression levels had lower diagnostic efficacy to differentiate PC from normal and BPH individuals with an area under curve (AUC) of 0.471 and 0.727, respectively. Further, survivin expression level was associated with increased the risk of PC. Conclusion Survivin and E2F3 relative expression levels in peripheral blood had low diagnostic performance to detect PC and individuals with high survivin expression levels may have higher risk to develop PC.

Akt inhibition-dependent downregulation of the Wnt/β-Catenin Signaling pathway contributes to antimony-induced neurotoxicity

Antimony (Sb), as a newly identified nerve poison, can lead to neuronal apoptosis. However, its neurotoxicological mechanisms remain largely unclear. Here, we evaluated the role and regulation of Wnt/β-catenin pathway in Sb-mediated neurotoxicity. Under Sb treatment, β-catenin was dramatically downregulated in vivo and in vitro. Moreover, overexpression of β-catenin effectively attenuated Sb-induced survivin gene expression suppression and subsequent apoptosis in PC12 cells. In addition, Sb stimualted glycogen synthase kinase-3β (GSK-3β) activation, shown as decreased phosphorylation levels at Ser 9 both in PC12 cells and mice brain. Paramacological inhibition of GSK-3β using lithium chloride (LiCl) significantly rescued β-catenin expression. For upstream pathway analysis, we found Sb treatment decreased protein kinase B (Akt) phosphorylation, and Akt activator protected PC12 cells from GSK-3β activation and subsequent β-catenin suppression. In summary, our data provided a novel molecular mechanism of Sb-associated neurotoxicity, namely that Sb induces Wnt/β-catenin pathway suppression through Akt inhibition, thus resulted in neuronal apoptosis.

Abstract B070: Mitotic kinases differentially phosphorylate survivin in African American TNBC: Clues for racial disparity

Abstract Protein diversity arising from alternative mRNA splicing or post-translational modifications (PTM) such as phosphorylation, methylation etc. plays a vital role in the modulation of cellular functions. Mitotic kinases such as polo-like kinase 1 (PLK1) and aurora B (AURKB) are known to phosphorylate survivin, an inhibitor of apoptosis family member, to promote cell survival and proliferation. This triad is significantly overexpressed in triple negative breast cancer (TNBC), an aggressive breast cancer (BC) subtype, associated with high proliferative capacity, propensity for distant metastasis and chemotherapeutic resistance. TNBC disproportionately afflicts African-American (AA) women relative to European-American (EA) women. AAs demonstrate a much more aggressive disease course compared to EAs. Thus far, efforts to examine molecular underpinnings of racial disparity in TNBC have largely focused on differences in gene expression and epigenetic aspects. Herein, we demonstrate the role of survivin phosphorylation, an important PTM, in enhancing cell proliferation and reducing apoptosis in AA compared to EA TNBC cells. Using the TCGA breast cancer dataset, our in silico analysis of various mitotic kinases yielded a significantly higher gene expression of PLK1 (p=0.061) and AURKB (p=0.003) in AA (n=41) compared to EA TNBC (n=86) patients. Surprisingly, we found no race-related differences in survivin gene expression in this dataset (n=127, p=0.343). In addition, there was no statistical difference in protein levels of survivin in TNBC clinical samples (n=142, p=0.45) as measured immunohistochemically. These findings led us to rationalize that the differential activation of survivin in AA vs. EA TNBC cells is based on PTM, and not due to its differential gene/protein expression levels. We hypothesize that differential phosphorylation of survivin by mitotic kinases underlies enhanced proliferative and anti-apoptotic activity in AA relative to EA TNBC. Survivin phosphorylation at Ser-20 and Thr-117 is known to regulate the activity of the chromosome passenger complex facilitating mitosis and cell proliferation. Moreover, p-survivin Thr-117 inhibits X-linked inhibitor of apoptosis-Smac interaction, which in turn prevents caspase-9 activation, leading to anti-apoptosis. We observed an upregulation of phosphorylated substrates of PLK1 and AURKB viz. p-survivin Ser-20 &amp; p-survivin Thr-117, respectively, in AA compared to EA TNBC cells. Survivin ablation significantly attentuated cell proliferation, cell cycle progression, and increased cell apoptosis in AA compared to EA TNBC cells. These data strongly support our premise that higher survivin phosphorylation confers enhanced proliferative capacity and anti-apoptosis in AA compared to EA TNBC cells, suggesting that modulating survivin PTM may be a viable therapeutic strategy for AA TNBC patients. Further studies intended to tease out the role of survivin phosphorylation in TNBC racial disparity are currently underway in our lab. Citation Format: Shriya Joshi, Chakravarthy Garlapati, Luciane Cavalli, Uma Krishnamurti, Shobhna Kapoor, Ritu Aneja. Mitotic kinases differentially phosphorylate survivin in African American TNBC: Clues for racial disparity [abstract]. In: Proceedings of the Twelfth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2019 Sep 20-23; San Francisco, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl_2):Abstract nr B070.