2-Methoxyestradiol attenuates phosphatidylinositol 3-kinase/Akt pathway-mediated metastasis of gastric cancer

2-Methoxyestradiol inhibits carotid artery intimal hyperplasia induced by balloon injury via inhibiting JAK/STAT axis in rats

Intimal hyperplasia (IH) is a common complication of vascular interventional procedures that leads to narrowing of the vessel lumen. 2-Methoxyestradiol (2ME), an estrogen metabolite, has numerous pharmacological actions, including vasoprotective and antiproliferative activities. The present study aimed to evaluate the potential of 2ME, prepared as a self-nanoemulsifying drug delivery system (SNEDDS), to inhibit IH induced by balloon injury (BI) in the rat carotid artery. The prepared 2ME SNEDDS had a particle size of 119 ± 2.3 nm and a zeta potential of -7.1 ± 1.4 mV. Animals were divided into 5 groups, namely control, sham, BI, BI + 2ME (100 μg/kg), and BI + 2ME (250 μg/kg). The obtained data indicated that 2ME significantly inhibited IH as indicated by the histological and morphometric assessment of the intima, media and lumen areas. This was associated with enhanced expression of Bax and inhibited expression of Bcl2 mRNA. Furthermore, 2ME exhibited significant antioxidant properties as evidenced by prevention of malondialdehyde accumulation as well as superoxide dismutase and catalase enzymatic exhaustion. In addition, 2ME showed significant anti-inflammatory actions as it significantly inhibited vascular content of interleukin-6, tumor necrosis factor-alpha, and nuclear factor-κB. The observed vasoprotective activities of 2ME were accompanied by inhibition of Janus kinase/signal transducers and activators of transcription (JAK/STAT) protein expression. In conclusion, this study revealed that 2ME ameliorates balloon injury-induced IH in rats via suppressing JAK/STAT axis. This may help to develop new strategies to combat IH.

Treatment with 2-methoxyestradiol increases endothelial nitric oxide synthase activity via scavenger receptor class BI in human umbilical vein endothelial cells

Concentrations of 2-methoxyestradiol (2ME2), a principal metabolite of estradiol, are significantly lower in women with severe preeclampsia. Nitric oxide (NO) released by endothelial nitric oxide synthase (eNOS) plays an important role in regulating cardiovascular homeostasis. Importantly, high-density lipoprotein (HDL) stimulates eNOS activity via endothelial human scavenger receptor class B type I (hSR-BI/CLA-1). Here, we aimed to determine the effect of 2ME2 on hSR-BI/CLA-1 expression in human umbilical vein endothelial cells (HUVECs). hSR-BI/CLA-1 expression was measured by real-time PCR, western blotting and reporter gene assays; eNOS activity was assessed by the measurement of eNOS phosphorylation. Both the mRNA and protein concentrations of hSR-BI/CLA-1 were significantly increased by 2ME2 in HUVECs. 2ME2 also dose-dependently increased the transcriptional activity of the hSR-BI/CLA-1 promoter. The effect of 2ME2 treatment on the promoter activity of hSR-BI/CLA-1 was abrogated by treatment with LY294002, a specific inhibitor of phosphatidylinositol 3-kinase, as was the increase in HDL-induced eNOS activation. Notably, constitutively active Akt increased the activity of the hSR-BI/CLA-1 promoter, whereas dominant-negative Akt abolished the effect of 2ME2 treatment on hSR-BI/CLA-1 promoter activity. The nuclear Sp1 protein concentration was significantly increased by exposure to 2ME2 and Sp1 overexpression increased the promoter activity of the hSR-BI/CLA gene. Furthermore, knockdown of Sp1 inhibited the effect of 2ME2 treatment on hSR-BI/CLA-1 protein expression. These results indicate that 2ME2 treatment increases HDL-dependent eNOS phosphorylation by upregulating endothelial hSR-BI/CLA-1 expression, suggesting that 2ME2 has a potential therapeutic value in the treatment of preeclampsia.

Latcripin-7A, derivative of Lentinula edodes C91-3, reduces migration and induces apoptosis, autophagy, and cell cycle arrest at G1 phase in breast cancer cells

Due to the high mortality rate and an increase in breast cancer incidence, it has been challenging for researchers to come across an effective chemotherapeutic strategy with minimum side effects. Therefore, the need for the development of effective chemotherapeutic drugs is still on the verge. Consequently, we approached a new mechanism to address this issue. The naturally available peptide named latcripin-7A (LP-7A), extracted from a mushroom called Lentinula edodes, provided us promising results in terms of growth arrest, apoptosis, and autophagy in breast cancer cells (MCF-7 and MDA-MB-231). Expressions of protein markers for apoptosis, autophagy, and cell cycle were confirmed via Western blot analysis. Migration and invasion assays were performed to analyze the anti-migratory and anti-invasive properties of LP-7A, while cell cycle analysis was performed via flow cytometry to evaluate its affect over cell growth. Supportive assays were performed like acridine orange, Hoechst 33258 stain, DNA fragmentation, and mitochondrial membrane potential (MMP) to further confirm the anticancer effect of LP-7A on breast cancer cell lines. It is concluded that LP-7A effectively reduces migration and promotes apoptosis as well as autophagy in MCF-7 and MDA-MB-231 breast cancer cell lines by inducing cell growth arrest at G₀/G₁ phase and decreasing mitochondrial membrane potential without adverse effects on MCF-10A normal breast cells. KEY POINTS: • In this study, we have investigated the anti-cancer activity of novel latcripin-7A (LP-7A), a protein extracted as a result of de novo characterization of Lentinula edodes C_91-3. • We conclude in our research work that LP-7A can initiate diverse cell death-related events, i.e., apoptosis and autophagy in both triple-positive and triple-negative breast cancer cell lines by interacting with different nodes of cellular signaling that can further be investigated in vivo to gain a better understanding.

Expression of endoplasmic reticulum oxidoreductase 1-α in cholangiocarcinoma tissues and its effects on the proliferation and migration of cholangiocarcinoma cells

Abstract

Endoplasmic reticulum oxidoreductase 1-α (ERO1A) is a kind of hypoxia-induced endoplasmic reticulum oxidase that regulates translation and folding of oxidized proteins. This study aimed to explore the clinicopathological significance of ERO1A and the effect on the biological behavior of cholangiocarcinoma (CCA) cells.

Methods

Immunohistochemical staining was used to detect the expression of ERO1A, carcinoembryonic antigen (CEA), and carbohydrate antigen 19–9 (CA19-9) in cholangiocarcinoma. Immunofluorescence staining was performed to detect the subcellular localization of ERO1A in CCA cells. The expression of ERO1A in CAA cells after depletion or overexpression was verified by Western blot assay. Then, the effect of ERO1A on proliferation in CCA cells was verified by MTT assay and colony formation assay. Wound healing assays and migration assays were performed to detect the effect of ERO1A on cell migration ability. Finally, we explored the role of ERO1A in EMT and Akt/mTOR signaling pathway.

Results

In this study, our data demonstrated that ERO1A, CEA, and CA19-9 were expressed in cholangiocarcinoma tissues, and the positive rates were 95%, 95%, and 55%, respectively. The high expression of ERO1A is associated with clinical stage and pathological stage of CCA. In vitro data indicate that deletion of ERO1A can inhibit the proliferation and migration of CCA cells and vice versa. In addition, ERO1A has been shown to be closely related to EMT and Akt/mTOR pathways.

Conclusion

In summary, we found that high expression of ERO1A is associated with poor prognosis in patients, and ERO1A can promote the proliferation and migration of CCA cells. In conclusion, ERO1A can be used as an independent biomarker for predicting the prognosis of CCA.

MiR-326/Sp1/KLF3: A novel regulatory axis in lung cancer progression

OBJECTIVES

To investigate the function and regulatory mechanism of Krüppel-like factor 3 (KLF3) in lung cancer.

MATERIALS AND METHODS

KLF3 expression was analysed by qRT-PCR and Western blot assays. The proliferation, migration, invasion, cycle and apoptosis were measured by CCK-8 and EdU, wound-healing and Transwell, and flow cytometry assays. The tumour growth was detected by nude mouse tumorigenesis assay. In addition, the interaction between KLF3 and Sp1 was accessed by luciferase reporter, EMSA and ChIP assay. JAK2, STAT3, PI3K and p-AKT levels were evaluated by Western blot and IHC assays.

RESULTS

The results indicated that KLF3 expression was elevated in lung cancer tissues. Knockdown of KLF3 inhibited lung cancer cell proliferation, migration and invasion, and induced cell cycle arrest and apoptosis. In addition, the downregulation of KLF3 suppressed tumour growth in vivo. KLF3 was transcriptionally activated by Sp1. miR-326 could bind to 3'UTR of Sp1 but not KLF3 and decreased the accumulation of Sp1, which further indirectly reduced KLF3 expression and inactivated JAK2/STAT3 and PI3K/AKT signaling pathways in vitro and in vivo.

CONCLUSIONS

Our data demonstrate that miR-326/Sp1/KLF3 regulatory axis is involved in the development of lung cancer, which hints the potential target for the further therapeutic strategy against lung cancer.

LP1 from Lentinula edodes C91-3 Induces Autophagy, Apoptosis and Reduces Metastasis in Human Gastric Cancer Cell Line SGC-7901

Present study aimed to elucidate the anticancer effect and the possible molecular mechanism underlying the action of Latcripin 1 (LP1), from the mushroom Lentinula edodes strain C91-3 against gastric cancer cell lines SGC-7901 and BGC-823. Cell viability was measured by Cell Counting Kit-8 (CCK-8); morphological changes were observed by phase contrast microscope; autophagy was determined by transmission electron microscope and fluorescence microscope. Apoptosis and cell cycle were assessed by flow cytometer; wound-healing, transwell migration and invasion assays were performed to investigate the effect of LP1 on gastric cancer cell's migration and invasion. Herein, we found that LP1 resulted in the induction of autophagy by the formation of autophagosomes and conversion of light chain 3 (LC3I into LC3II. LP1 up-regulated the expression level of autophagy-related gene (Atg7, Atg5, Atg12, Atg14) and Beclin1; increased and decreased the expression level of pro-apoptotic (Bax) and anti-apoptotic (Bcl-2) proteins respectively, along with the activation of Caspase-3. At lower-doses, LP1 have shown to arrest cells in the S phase of the cell cycle and decreased the expression level of matrix metalloproteinase MMP-2 and MMP-9. In addition, it has also been shown to regulate the phosphorylation of one of the most hampered gastric cancer pathway, that is, protein kinase B/mammalian target of rapamycin (Akt/mTOR) channel and resulted in cell death. These findings suggested LP1 as a potential natural anti-cancer agent, for exploring the gastric cancer therapies and as a contender for further in vitro and in vivo investigations.

2-Methoxyestradiol Attenuates Testosterone-Induced Benign Prostate Hyperplasia in Rats through Inhibition of HIF-1α/TGF-β/Smad2 Axis

Benign prostatic hyperplasia (BPH) is a common disorder in the male population. 2-Methoxyestradiol (2ME) is an end metabolite of estrogens with pleiotropic pharmacological properties. This study aimed to explore the potential ameliorative effects of 2ME against testosterone-induced BPH in rats. 2-Methoxyestradiol (50 and 100 mg/kg, dissolved in DMSO) prevented the rise in prostatic index and weight in comparison to testosterone-alone-treated animals for 2 weeks. Histological examination indicated that 2ME ameliorated pathological changes in prostate architecture. This was confirmed by the ability of 2ME to decrease the glandular epithelial height when compared to the testosterone group. Also, 2ME improved testosterone-induced oxidative stress as it inhibited the rise in lipid peroxide content and the exhaustion of superoxide dismutase (SOD) activity. The beneficial effects of 2ME against the development of BPH were substantiated by assessing proliferation markers, preventing the rise in cyclin D1 protein expression and enhancing Bax/Bcl2 mRNA ratio. It significantly reduced prostate content of tumor necrosis factor α (TNF-α), interleukin-1β (IL-1β), nuclear factor κB (NF-κB), and transforming growth factor β (TGF-β). In addition, 2ME reduced hypoxia-inducible factor 1-α (HIF-1α) and phospho-Smad2 (p-Smad2) protein expression compared to the testosterone group. In conclusion, 2ME attenuates experimentally induced BPH by testosterone in rats through, at least partly, inhibition of HIF-1α/TGF-β/Smad2 axis.

KIFC1, a novel potential prognostic factor and therapeutic target in hepatocellular carcinoma

Kinesin family member C1 (KIFC1, also known as HSET) is a minus end-directed motor protein, which is critical in centrosome clustering. The present study investigated the expression of KIFC1 in paired hepatocellular carcinoma (HCC) tissues and adjacent non-cancerous tissues from 91 patients by immunohistochemical analysis; clinical data were concomitantly collected. KIFC1 was expressed at high levels in HCC tissues, compared with that in peritumoral tissues (54.9 vs. 14.3%; P<0.01), and its expression correlated with tumor emboli, metastasis, recurrence and time of recurrence. Kaplan-Meier analysis showed that the expression of KIFC1 was significantly associated with tumor-free survival rates. In addition, multivariate analyses revealed that the overexpression of KIFC1was an independent predictive marker in patients with HCC. Consistently, data derived from GEPIA was in agreement with the results. In vitro, KIFC1 knockdown effectively decreased HCC cell viability, and induced apoptosis and cell death. KIFC1 knockdown also significantly suppressed tumor cell migration and invasion in vitro. Mechanistically, the apoptosis-related protein, B-cell lymphoma-2 (Bcl-2), was downregulated in KIFC1 small interfering RNA-treated groups, whereas thee levels of Bcl-2-associated X protein and p53 were upregulated. In addition, the expression levels of phosphorylated phosphoinositide 3-kinase and phosphorylated AKT were decreased significantly when KIFC1 was silenced. The epithelial-mesenchymal transition-related proteins, N-cadherin, matrix metalloproteinase-2 (MMP-2), β-catenin, Slug, and Zinc finger E-box-binding homeobox 1, were downregulated, whereas the expression of E-cadherin was upregulated. The overexpression of KIFC1 was correlated closely with the progression of HCC and poor prognosis, and suggested that the expression levels of KIFC1 are a potential prognostic biomarker and therapeutic target in HCC.

Three-microRNA signature identified by bioinformatics analysis predicts prognosis of gastric cancer patients

AIM

To identify multiple microRNAs (miRNAs) for predicting the prognosis of gastric cancer (GC) patients by bioinformatics analysis.

METHODS

The original microarray dataset GSE93415, which included 20 GC and 20 tumor adjacent normal gastric mucosal tissues, was downloaded from the Gene Expression Omnibus database and used for screening differentially expressed miRNAs (DEMs). The cut-off criteria were P < 0.05 and fold change > 2.0. In addition, we acquired the miRNA expression profiles and clinical information of 361 GC patients from The Cancer Genome Atlas database to assess the prognostic role of the DEMs. The target genes of miRNAs were predicted using TargetScan, miRDB, miRWalk, and DIANA, and then the common target genes were selected for functional enrichment analysis.

RESULTS

A total of 110 DEMs including 19 up-regulated and 91 down-regulated miRNAs were identified between 20 pairs of GC and tumor adjacent normal tissues, and the Kaplan-Meier survival analysis found that a three-miRNA signature (miR-145-3p, miR-125b-5p, and miR-99a-5p) had an obvious correlation with the survival of GC patients. Furthermore, univariate and multivariate Cox regression analyses indicated that the three-miRNA signature could be a significant prognostic marker in GC patients. The common target genes of the three miRNAs are added up to 108 and used for Gene Functional Enrichment analysis. Biological Process and Molecular Function analyses showed that the target genes are involved in cell recognition, gene silencing and nucleic acid binding, transcription factor activity, and transmembrane receptor activity. Cellular Component analysis revealed that the genes are portion of nucleus, chromatin silencing complex, and TORC1/2 complex. Biological Pathway analysis indicated that the genes participate in several cancer-related pathways, such as the focal adhesion, PI3K, and mTOR signaling pathways.

CONCLUSION

This study justified that a three-miRNA signature could play a role in predicting the survival of GC patients.

Cryptotanshinone induces cell cycle arrest and apoptosis through the JAK2/STAT3 and PI3K/Akt/NFκB pathways in cholangiocarcinoma cells

BACKGROUND

Cholangiocarcinoma (CCA) is the most common biliary tract malignancy in the world with high resistance to current chemotherapies and extremely poor prognosis. The main objective of this study was to investigate the inhibitory effects of cryptotanshinone (CTS), a natural compound isolated from Salvia miltiorrhiza Bunge, on CCA both in vitro and in vivo and to explore the underlying mechanisms of CTS-induced apoptosis and cell cycle arrest.

METHODS

The anti-tumor activity of CTS on HCCC-9810 and RBE cells was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) assay and colony forming assays. Cell cycle changes were detected by flow cytometric analysis. Apoptosis was detected by annexin V/propidium iodide double staining and Hoechst 33342 staining assays. The efficacy of CTS in vivo was evaluated using a HCCC-9810 xenograft model in athymic nude mice. The expression of key proteins involved in cell apoptosis and signaling pathway in vitro was analyzed by Western blot analysis.

RESULTS

CTS induced potent growth inhibition, S-phase arrest, apoptosis, and colony-forming inhibition in HCCC-9810 and RBE cells in a dose-dependent manner. Intraperitoneal injection of CTS (0, 10, or 25 mg/kg) for 4 weeks significantly inhibited the growth of HCCC-9810 xenografts in athymic nude mice. CTS treatment induced S-phase arrest with a decrease of cyclin A1 and an increase of cyclin D1 protein level. Bcl-2 expression was downregulated remarkably, while Bax expression was increased after apoptosis occurred. Additionally, the activation of JAK2/STAT3 and PI3K/Akt/NFκB was significantly inhibited in CTS-treated CCA cells.

CONCLUSION

CTS induced CCA cell apoptosis by suppressing both the JAK2/STAT3 and PI3K/Akt/NFκB signaling pathways and altering the expression of Bcl-2/Bax family, which was regulated by these two signaling pathways. CTS may serve as a potential therapeutic agent for CCA.

Luteolin induces apoptosis in vitro through suppressing the MAPK and PI3K signaling pathways in gastric cancer

Luteolin, an active component of traditional Chinese medicine, exhibits potential for anti-tumor proliferation; however, the molecular events occurring in such process and the signal transduction pathways involved are currently unknown. Our group previously reported that luteolin inhibited proliferation and induced apoptosis in the gastric cancer cell line BGC-823. The aim of the present study was to investigate the mechanism by which the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) signaling pathways regulate the apoptosis in vitro of BGC-823 cells following treatment with luteolin. It was observed that luteolin induced apoptosis through the intrinsic pathway by increasing the levels of caspase-3, caspase-9 and cytochrome c, and the ratio of B-cell lymphoma (Bcl)-2 associated X protein (Bax) to Bcl-2. Luteolin suppressed the phosphorylation of extracellular signal-regulated kinase in the MAPK signaling pathway, as well as suppressing the phosphorylation of AKT, PI3K and mechanistic target of rapamycin in the PI3K signaling pathway. In addition, luteolin combined with LY294002 markedly increased the Bax/Bcl-2 ratio, while when combined with U0126, luteolin had less effects on the Bax/Bcl-2 ratio compared with luteolin treatment alone, suggesting that both the MAPK and PI3K signaling pathways are involved in the apoptosis induced by luteolin. Furthermore, luteolin attenuated the MAPK and PI3K signaling pathways by increasing the expression of specific dual-specificity phosphatases and decreasing the expression of chemokine (C-X-C motif) ligand 16 at the messenger RNA level, respectively. Taken together, the present results demonstrate that luteolin is a potential chemotherapeutic agent against gastric cancer by exerting a dual inhibition on the MAPK and PI3K signaling pathways.

Mechanism of antiproliferative action of a new d-secoestrone-triazole derivative in cervical cancer cells and its effect on cancer cell motility

Cervical cancer is the fourth most frequently diagnosed tumor and the fourth leading cause of cancer death in females worldwide. Cervical cancer is predominantly related with human papilloma virus (HPV) infection, with the most oncogenic types being HPV-18 and -16. Our previous studies demonstrated that some d-secoestrone derivatives exert pronounced antiproliferative activity. The aim of the current investigation was to characterize the mechanism of action of d-secoestrone-triazole (D-SET) on three cervical cancer cell lines with different pathological backgrounds. The growth-inhibitory effects of D-SET were determined by a standard MTT assay. We have found that D-SET exerts a pronounced growth-inhibitory effect on HPV 18-positive HeLa and HPV-negative C-33 A cells, but it has no substantial inhibitory activity on HPV 16-positive SiHa or on intact fibroblast MRC-5 cell lines. After 24h incubation, cells showed the morphological and biochemical signs of apoptosis determined by fluorescent double staining, flow cytometry and caspase-3 activity assay. Besides the elevation of the ratio of cells in the subG1 phase, flow cytometric analysis revealed a cell cycle arrest at G2/M in both HeLa and C-33 A cell lines. To distinguish the G2/M cell population immunocytochemical flow cytometric analysis was performed on HeLa cells. The results show that D-SET significantly increases the ratio of phosphorylated histone H3, indicating cell accumulation in the M phase. Additionally, D-SET significantly increased the maximum rate of microtube formation measured by an in vitro tubulin polymerization assay. Besides its direct antiproliferative activity, the antimigratory property of D-SET has been investigated. Our results demonstrate that D-SET significantly inhibits the migration and invasion of HeLa cells after 24h incubation. These results suggests that D-SET is a potent antiproliferative agent against HPV 16+ and HPV-negative cervical cancer cell lines, with an efficacious motility-inhibiting activity against HPV 16+ cells. Accordingly D-SET can be regarded as a potential drug candidate with a promising new mechanism of action among the antiproliferative steroids, potentially allowing for the design of novel anticancer agents.

The natural secolignan peperomin E induces apoptosis of human gastric carcinoma cells via the mitochondrial and PI3K/Akt signaling pathways in vitro and in vivo

BACKGROUND

Peperomin E (PepE) is a type of secolignan that is a major component of the plant Peperomia dindygulensis. It has been shown to exert anticancer effects in various cancer cell lines; however, the effects of PepE on human gastric cancer remain unexplored.

PURPOSE

The aim of this study was to investigate the effectiveness of PepE as a treatment of gastric cancer and to identify the underlying mechanisms of its anticancer activity.

STUDY DESIGN

The efficacy of PepE was examined using human gastric carcinoma SGC-7901, BGC-823, MKN-45 cell lines and normal gastric epithelial GES-1 cell line as an in vitro model and SGC-7901 xenograft mice as an in vivo model.

METHODS

Cell viability assays were used to examine the anticancer effect of 0-204.8µM concentrations of PepE in vitro. Additionally, flow cytometry and western blotting were used to elucidate the mechanism with a particular focus on apoptosis. SGC-7901 cells were injected into BALB/c mice, which were then treated with 5 or 15mg/kg/day dose of PepE. The in vivo activity of PepE was investigated by measuring tumors and conducting immunohistochemistry experiments. The safety of PepE was investigated by measuring blood biochemical parameters and conducting histopathological analysis. Taxol was used throughout as a positive control.

RESULTS

The results showed that PepE exhibited antiproliferative effects against gastric cancer cells and induced their apoptosis in a dose dependent manner with lower toxicity against normal gastric epithelial cells. Mechanistic evaluations indicated that PepE induced apoptosis by reducing the mitochondrial membrane potential (MTP), inducing cytochrome C release from mitochondria, reducing the ratio of Bcl-2/Bax and Bcl-xl/Bad, increasing activation of caspase-3, and decreasing the levels of PI3K and pAkt. The apoptotic effect of PepE on SGC-7901 cells was partially blocked by an Akt activator SC79. PepE potently inhibited in vivo tumor growth with no obvious toxicity following subcutaneous inoculation of SGC-7901 cells in nude mice.

CONCLUSIONS

These findings indicate that PepE can inhibit cell proliferation and induce apoptosis of gastric cancer cells through mitochondrial and PI3K/Akt signaling pathways with relative safety and may be a novel effective chemotherapeutic agent against gastric cancer.

Recent Advances in chemistry and pharmacology of 2-methoxyestradiol: An anticancer investigational drug

2-Methoxyestradiol (2ME2), an estrogen hormone metabolite is a potential cancer chemotherapeutic agent. Presently, it is an investigational drug under various phases of clinical trials alone or in combination therapy. Its anticancer activity has been attributed to its antitubulin, antiangiogenic, pro-apoptotic and ROS induction properties. This anticancer drug candidate has been explored extensively in last twenty years for its detailed chemistry and pharmacology. Present review is an update of its chemistry and biological activity. It also extends an assessment of potential of 2ME2 and its analogues as possible anticancer drug in future.

Marine steroids as potential anticancer drug candidates: In silico investigation in search of inhibitors of Bcl-2 and CDK-4/Cyclin D1

Star fishes (Asteroidea) are rich in polar steroids with diverse structural characteristics. The structural modifications of star fish steroids occur at 3β, 4β, 5α, 6α (or β), 7α (or β), 8, 15α (or β) and 16β positions of the steroidal nucleus and in the side chain. Widely found polar steroids in starfishes include polyhydroxysteroids, steroidal sulfates, glycosides, steroid oligoglycosides etc. Bioactivity of these steroids is less studied; only a few reports like antibacterial, cytotoxic activity etc. are available. In continuation of our search for bioactive molecules from natural sources, we undertook in silico screening of steroids from star fishes against Bcl-2 and CDK-4/Cyclin D1 - two important targets of progression and proliferation of cancer cells. We have screened 182 natural steroids from star fishes occurring in different parts of the world and their 282 soft-derivatives by in silico methods. Their physico-chemical properties, drug-likeliness, binding potential with the selected targets, ADMET (absorption, distribution, metabolism, toxicity) were predicted. Further, the results were compared with those of existing steroidal and non steroidal drugs and inhibitors of Bcl-2 and CDK-4/Cyclin D1. The results are promising and unveil that some of these steroids can be potent leads for cancer treatments.

Single nucleotide polymorphisms in AREG and EREG are prognostic biomarkers in locally advanced gastric cancer patients after surgery with curative intent

OBJECTIVE

Amphiregulin (AREG) and epiregulin (EREG) are important ligands to the epithelial growth factor receptor, which is involved in the regulation of progression and stemness in gastric cancer (GC). This study investigated whether frequent single nucleotide polymorphisms (SNPs) in genes of AREG and EREG are associated with recurrence-free survival and overall survival in patients with locally advanced GC.

METHODS

SNPs with a minor allele frequency of at least 10% were analyzed using direct DNA sequencing in two independent study populations.

RESULTS

The minor allele of AREG rs1615111 was associated with a significantly higher 3-year recurrence rate and lower 3-year survival rate [hazard ratio (HR)=2.21 and 2.35, respectively] compared with patients homozygous for the dominant allele G. The value for overall survival could be validated with a HR of 2.54 (P=0.018) in an independent cohort. Patients homozygous for the minor allele A of EREG rs12641042 had a significantly higher 3-year survival rate than patients with allele C (HR 0.48; P=0.034), but significance was lost in multivariable analysis (P=0.066). The value of rs12641042 could not be validated (P=0.98). Exploratory multivariable subgroup analysis showed the strongest prognostic value for rs1615111 in tumors with a diffuse histology (Pfor interaction=0.004).

CONCLUSION

AREG rs1615111, located in the AREG genomic region, can significantly define different prognostic cohorts in locally advanced GC. This value is most evident in GC patients with diffuse histology, which might be relevant as none of the trials testing epithelial growth factor receptor inhibitors has been enriched for diffuse histology or a molecularly defined population.

2-methoxyestradiol induces vasodilation by stimulating NO release via PPARγ/PI3K/Akt pathway

The endogenous estradiol metabolite 2-methoxyestradiol (2-ME) reduces atherosclerotic lesion formation, while the underlying mechanisms remain obscure. In this work, we investigated the vasodilatory effect of 2-ME and the role of nitric oxide (NO) involved. In vivo studies using noninvasive tail-cuff methods showed that 2-ME decreased blood pressure in Sprague Dawley rats. Furthermore, in vitro studies showed that cumulative addition of 2-ME to the aorta caused a dose- and endothelium-dependent vasodilation. This effect was unaffected by the pretreatment with the pure estrogen receptor antagonist ICI 182,780, but was largely impaired by endothelial nitric oxide synthase (eNOS) inhibitor NG-nitro-L-arginine methyl ester (L-NAME) or by phosphoinositide 3-kinase (PI3K) inhibitor wortmannin (WM). Moreover, 2-ME（10^{−7 ∼}10⁻⁵ M）enhanced phosphorylation of Akt and eNOS and promoted NO release from cultured human umbilical endothelial cells (HUVECs). These effects were blocked by PI3K inhibitor WM, or by the transfection with Akt specific siRNA, indicating that endothelial Akt/eNOS/NO cascade plays a crucial role in 2-ME-induced vasodilation. The peroxisome proliferator-activated receptor γ (PPARγ) mRNA and protein expression were detected in HUVECs and the antagonist GW9662 or the transfection with specific PPARγ siRNA inhibited 2-ME-induced eNOS and Akt phosphorylation, leading to the impairment of NO production and vasodilation. In conclusion, 2-ME induces vasodilation by stimulating NO release. These actions may be mediated by PPARγ and the subsequent activation of Akt/eNOS cascade in vascular endothelial cells.

CD24 mediates gastric carcinogenesis and promotes gastric cancer progression via STAT3 activation

The development of gastric cancer (GC) is a complex multistep process, including numerous genetic and epigenetic changes. CD24 is associated with enhanced invasiveness of GC and a poor prognosis. However, the mechanism by which CD24 induces GC progression remains poorly characterized. Here, we found that the expression of CD24 gradually increased in samples of normal gastric mucosa, non-atrophic chronic gastritis, chronic atrophic gastritis (CAG), CAG with intestinal metaplasia, dysplasia and GC. Moreover, the knockdown of CD24 induced significant levels of apoptosis in GC cells via the mitochondrial apoptotic pathway. CD24 may also promote cellular invasion and regulate the expression of E-cadherin, fibronectin and vitamin D receptor in GC cells. The activation of signal transducer and activator of transcription 3 (STAT3) may mediate CD24-induced GC survival and invasion in vitro. Furthermore, CD24-induced GC progression and STAT3 activation could also be detected in vivo and in clinical GC tissues samples. Taken together, our results indicate that CD24 mediates gastric carcinogenesis and may promote GC progression by suppressing apoptosis and promoting invasion, with the activation of STAT3 playing a critical role.

The Role of PI3K/Akt/mTOR Signaling in Gastric Carcinoma

The phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathway is one of the key signaling pathways induced by various receptor-tyrosine kinases. Accumulating evidence shows that this pathway is an important promoter of cell growth, metabolism, survival, metastasis, and resistance to chemotherapy. Genetic alterations in the PI3K/Akt/mTOR pathway in gastric carcinoma have often been demonstrated. Many kinds of molecular targeting therapies are currently undergoing clinical testing in patients with solid tumors. However, with the exception of the ErbB2-targeting antibody, targeting agents, including PI3K/Akt/mTOR inhibitors, have not been approved for treatment of patients with gastric carcinoma. This review summarizes the current knowledge on PI3K/Akt/mTOR signaling in the pathogenesis of gastric carcinoma and the possible therapeutic targets for gastric carcinoma. Improved knowledge of the PI3K/Akt/mTOR pathway in gastric carcinoma will be useful in understanding the mechanisms of tumor development and for identifying ideal targets of anticancer therapy for gastric carcinoma.

The therapeutic value of targeting inflammation in gastrointestinal cancers

Inflammation has been implicated in the initiation and progression of gastrointestinal (GI) cancers. Inflammation also plays important roles in subverting immune tolerance, escape from immune surveillance, and conferring resistance to chemotherapeutic agents. Targeting key regulators and mediators of inflammation represents an attractive strategy for GI cancer prevention and treatment. However, the targeting of inflammation in GI cancer is not straightforward and sometimes inflammation may contribute to tumor regression. We discuss the origins and effects of inflammation in GI cancer and how to target it successfully.

Akt-p53-miR-365-cyclin D1/cdc25A axis contributes to gastric tumorigenesis induced by PTEN deficiency

Although PTEN/Akt signaling is frequently deregulated in human gastric cancers, the in vivo causal link between its dysregulation and gastric tumorigenesis has not been established. Here we show that inactivation of PTEN in mouse gastric epithelium initiates spontaneous carcinogenesis with complete penetrance by 2 months of age. Mechanistically, activation of Akt suppresses the abundance of p53, leading to decreased transcription of miR-365, thus causing upregulation of cyclin D1 and cdc25A, which promotes gastric cell proliferation. Importantly, genetic ablation of Akt1 restores miR-365 expression and effectively rescues gastric tumorigenesis in PTEN-mutant mice. Moreover, orthotopic restoration of miR-365 represses PTEN-deficient-induced hyperplasia. In human gastric cancer tissues, miR-365 reduction correlates with poorly differentiated histology, deep invasion and advanced stage, as well as the deregulation of PTEN, phosphorylated Akt, p53, cyclin D1 and cdc25A. These data demonstrate that the PTEN-Akt-p53-miR-365-cyclin D1/cdc25A axis serves as a new mechanism underlying gastric tumorigenesis, providing potential new therapeutic targets.

Gastrin acting on the cholecystokinin2 receptor induces cyclooxygenase-2 expression through JAK2/STAT3/PI3K/Akt pathway in human gastric cancer cells. Cancer Lett. 2013;332:11-18. [PMID: 23376640 DOI: 10.1016/j.canlet.2012.12.030]

Gastrin, cholecystokinin2 receptor (CCK2R), and cyclooxygenase-2 (COX-2) have been implicated in the carcinogenesis and progression of gastric cancer. Our study demonstrated that antagonist or siRNA against CCK2R blocked amidated gastrin (G17)-induced activation of STAT3 and Akt in gastric cancer cell lines. G17-increased COX-2 expression and cell proliferation were effectively blocked by CCK2R antagonist and inhibitors of JAK2 and PI3K. In addition, knockdown of STAT3 expression significantly attenuated G17-induced PI3K/Akt activation, COX-2 expression, and cell proliferation. These results suggest that CCK2R-mediated COX-2 up-regulation via JAK2/STAT3/PI3K/Akt pathway is involved in the proliferative effect of G17 on human gastric cancer cells.

Identification of significant pathways in gastric cancer based on protein-protein interaction networks and cluster analysis

Gastric cancer is one of the most common and lethal cancers worldwide. However, despite its clinical importance, the regulatory mechanisms involved in the aggressiveness of this cancer are still poorly understood. A better understanding of the biology, genetics and molecular mechanisms of gastric cancer would be useful in developing novel targeted approaches for treating this disease. In this study we used protein-protein interaction networks and cluster analysis to comprehensively investigate the cellular pathways involved in gastric cancer. A primary immunodeficiency pathway, focal adhesion, ECM-receptor interactions and the metabolism of xenobiotics by cytochrome P450 were identified as four important pathways associated with the progression of gastric cancer. The genes in these pathways, e.g., ZAP70, IGLL1, CD79A, COL6A3, COL3A1, COL1A1, CYP2C18 and CYP2C9, may be considered as potential therapeutic targets for gastric cancer.

2-Methoxyestradiol causes functional repression of transforming growth factor β3 signaling by ameliorating Smad and non-Smad signaling pathways in immortalized uterine fibroid cells

OBJECTIVE

To investigate the effects and the mechanism of action of 2-methoxyestradiol (2ME(2)) on transforming growth factor (TGF) β3-induced profibrotic response in immortalized human uterine fibroid smooth muscle (huLM) cells.

DESIGN

Laboratory study.

SETTING

University research laboratory.

PATIENTS(S)

Not applicable.

INTERVENTIONS(S)

Not applicable.

MAIN OUTCOME MEASURE(S)

huLM cells were treated with TGF-β3 (5 ηg/mL) in the presence or absence of specific Smad3 inhibitor SIS3 (1 μmol/L), inhibitor of the PI3K/Akt (LY294002, 10 μmol/L), or 2ME(2) (0.5 μmol/L), and the expression of collagen (Col) type I(αI), Col III(αI), plasminogen activator inhibitor (PAI) 1, connective tissue growth factor (CTGF), and α-smooth muscle actin (α-SMA) were determined by real-time reverse-transcription polymerase chain reaction and immunoblotting. The effect of 2ME(2) on Smad-microtubule binding was evaluated by coimmunoprecipitation.

RESULT(S)

Our data revealed that TGF-β3-induced fibrogenic response in huLM is mediated by both Smad-dependent and Smad-independent PI3K/Akt/mTOR signaling pathways. 2ME(2) abrogates TGF-β3-induced expression of Col I(αI), Col III(αI), PAI-1, CTGF, and α-SMA. Molecularly, 2ME(2) ameliorates TGF-β3-induced Smad2/3 phosphorylation and nuclear translocation. In addition, 2ME(2) inhibits TGF-β3-induced activation of the PI3K/Akt/mTOR pathway.

CONCLUSION(S)

TGF-β3-induced profibrotic response in fibroid cells is mediated by Smad-dependent and Smad-independent PI3K/Akt/mTOR pathways. 2ME(2) inhibits TGF-β3 profibrotic effects in huLM cells by ameliorating both Smad-dependent and Smad-independent signaling pathways.

Magnolol, a natural compound, induces apoptosis of SGC-7901 human gastric adenocarcinoma cells via the mitochondrial and PI3K/Akt signaling pathways

Gastric cancer is the fourth most commonly diagnosed cancer with the second highest mortality rate worldwide. Surgery, chemotherapy and radiation therapy are generally used for the treatment of stomach cancer but only limited clinical response is shown by these therapies and still no effectual therapy for advanced gastric adenocarcinoma patients is available. Therefore, there is a need to identify other therapeutic agents against this life-threatening disease. Plants are considered as one of the most important sources for the development of anticancer drugs. Magnolol, a natural compound possesses anticancer properties. However, effects of Magnolol on human gastric cancer remain unexplored. The effects of Magnolol on the viability of SGC-7901 cells were determined by the MTT assay. Apoptosis, mitochondrial membrane potential and cell cycle were evaluated by flow cytometry. Protein expression of Bcl-2, Bax, caspase-3 and PI3K/Akt was analysed by Western blotting. Magnolol induced morphological changes in SGC-7901 cells and its cytotoxic effects were linked with DNA damage, apoptosis and S-phase arrest in a dose-dependent manner. Magnolol triggered the mitochondrial-mediated apoptosis pathway as shown by an increased ratio of Bax/Bcl-2, dissipation of mitochondrial membrane potential (ΔΨm), and sequential activation of caspase-3 and inhibition of PI3K/Akt. Additionally, Magnolol induced autophagy in SGC-7901 cells at high concentration but was not involved in cell death. Magnolol-induced apoptosis of SGC-7901 cells involves mitochondria and PI3K/Akt-dependent pathways. These findings provide evidence that Magnolol is a promising natural compound for the treatment of gastric cancer and may represent a candidate for in vivo studies of monotherapies or combination antitumor therapies.

2D/3D-QSAR STUDY ON ANALOGUES OF 2-METHOXYESTRADIOL WITH ANTICANCER ACTIVITY

Two-dimensional (2D) and three-dimensional (3D) quantitative structure–activity relationships (QSARs) of 23 analogs of 2-Methoxyestradiol with anticancer activity (expressed as p GI50) against MCF-7 human breast cancer cells have been studied by using a combined method of the DFT, MM2 and statistics for 2D, as well as the comparative molecular field analysis (CoMFA) for 3D. The established 2D-QSAR model in training set shows not only significant statistical quality, but also predictive ability, with the square of adjusted correlation coefficient [Formula: see text] and the square of the cross-validation coefficient (q2= 0.779). The same model was further applied to predict p GI50values of the four compounds in the test set, and the resulting [Formula: see text] being as high as 0.827, further confirms that this 2D-QSAR model has high predictive ability for this kind of compound. The 3D-QSAR model also shows good correlative and predictive capabilities in terms of R2(0.927) and q2(0.786) obtained from CoMFA model. The results that 2D- and 3D-QSAR analyses accord with each other, suggest that the electrostatic interaction plays a decisive role in determining the anticancer activity of the studied compounds, and that increasing the negative charge of substituent R2and the positive charge of substituents linking to C17as well as decreasing the size of substituent R1are advantageous to improving the cytotoxicity. Such results can offer some useful theoretical references for directing the molecular design and understanding the action mechanism of this kind of compound with anticancer activity.

Overexpression of miR-370 and downregulation of its novel target TGFβ-RII contribute to the progression of gastric carcinoma

MicroRNAs (miRNAs) are endogenous non-coding RNAs that are known to be involved in the pathogenesis of tumors. Gastric carcinoma (GC) is a common malignancy worldwide. The aim of this study was the identification of the expression signature and functional roles of aberrant miRNAs in GC. Initial screening established a profile of aberrantly expressed miRNAs in tumors. miR-370 was confirmed to be overexpressed in GC tissues. Higher expression of miR-370 in GC tissues was associated with more advanced nodal metastasis and a higher clinical stage compared with controls. In addition, significantly higher level of miR-370 was noted in the plasma of GC patients compared with controls. Patients having more invasive or advanced tumors also exhibited a higher plasma level of miR-370. In vitro assays indicated that exogenous miR-370 expression enhanced the oncogenic potential of GC cells. The AGS-GFPM2 cells with exogenous miR-370 expression also exhibited enhanced abdominal metastatic dissemination in nude mice. Reporter assays confirmed that miR-370 targeted predicted sites in 3'UTR of transforming growth factor-β receptor II (TGFβ-RII) gene. The exogenous miR-370 expression decreased TGFβ-RII expression and the phosphorylation of Smad3 elicited by TGFβ1. The TGFβ1-mediated repression in cell migration was reverted by exogenous miR-370 expression. A reverse correlation between miR-370 and TGFβ-RII expression was noted in GC tissues. This study concludes that miR-370 is a miRNA that is associated with GC progression by downregulating TGFβ-RII. The miRNA expression profile described in this study should contribute to future studies on the role of miRNAs in GC.

Programmed cell death 4 (PDCD4) enhances the sensitivity of gastric cancer cells to TRAIL-induced apoptosis by inhibiting the PI3K/Akt signaling pathway

OBJECTIVE

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is thought to be a promising anti-neoplastic agent because of its ability to selectively induce apoptosis in cancer cells. However, some cancer cells are resistant to TRAIL. The mechanisms underlying this resistance are unclear. The aim of this study was to explore the role of programmed cell death 4 (PDCD4) in regulating TRAIL sensitivity in gastric cancer cells.

METHODS

PDCD4 complementary DNA and PDCD4-specific short-hairpin RNA (shRNA) fragments were transfected into TRAIL-sensitive and -resistant gastric cancer cells. Expression of PDCD4 and Akt was detected via western blot. Cell survival and apoptosis were measured using 3-(4,5-dimethylthiazolyl)-2,5-diphenyltetrazolium bromide (MTT) and flow cytometry (FCM) assays.

RESULTS

We found that upregulation of PDCD4 enhanced TRAIL sensitivity in gastric cancer cells. Downregulation of PDCD4 decreased TRAIL sensitivity. Inhibition of Akt by the phosphoinositide 3-kinase (PI3K) inhibitor LY294002 induced PDCD4 activity and enhanced TRAIL sensitivity in TRAIL-resistant gastric cancer cells.

CONCLUSION

We demonstrated that PDCD4 regulates TRAIL sensitivity in gastric cancer cells by inhibiting the PI3K/Akt signaling pathway.

2-Methoxyestradiol-induced radiosensitization is independent of SOD but depends on inhibition of Akt and DNA-PKcs activities

BACKGROUND AND PURPOSE

2-Methoxyestradiol (2-ME) is described as an inhibitor of the superoxide dismutase (SOD) enzyme activity. However, it attenuates PI3K/Akt pathway and induces radiosensitization in human tumor cells as well. Since the activation of catalytic subunit of DNA-protein kinase (DNA-PKcs) is partially regulated by Akt activity, in the present study we investigated whether 2-ME-induced radiosensitization is dependent on inhibition of Akt and DNA-PKcs activities or on SOD targeting.

MATERIALS AND METHODS

This study was performed using the lung carcinoma cell line A549. Ionizing radiation-induced SOD activity was analyzed by superoxide dismutase activity assay. Applying Western blotting, the pattern of radiation-induced SOD expression and activation of Akt as well as DNA-PKcs was analyzed. Colony formation assay and gammaH2AX foci assay were performed to measure radiosensitization and DNA-double strand break (DNA-DSB) repair. To downregulate SOD expression small interfering RNA (siRNA) was used.

RESULTS

Irradiation with 4Gy stimulated SOD enzyme activity as early as 1min after radiation exposure. Expression of Cu/Zn-SOD (SOD1) as well as Mn-SOD (SOD2) was increased by single doses of 1-4Gy within 24-36h. 2-ME blocked radiation-induced SOD enzyme activity but not protein expression and enhanced radiation sensitivity. Pretreatment with 2-ME blocked IR-induced Akt as well as DNA-PKcs phosphorylation and impaired the repair of DNA-DSB. SiRNA targeting of SOD1 and SOD2 affected neither DNA-PKcs phosphorylation nor post-irradiation survival while inhibition of Akt by specific inhibitor abrogated 2-ME-induced radiosensitization.

CONCLUSION

These results may indicate that 2-ME-induced radiosensitization is independent of SOD inhibition but mainly depends on inhibition of Akt and DNA-PKcs activities.

Targeting apoptosis as an approach for gastrointestinal cancer therapy. Drug Resist Updat. 2009;12:55-64. [PMID: 19278896 DOI: 10.1016/j.drup.2009.02.002]

Cancers in the gastrointestinal system account for a large proportion of malignancies and cancer-related deaths with gastric cancer and colorectal cancer being the most common ones. For those patients in whom surgical resection is not possible, other therapeutic approaches are necessary. Disordered apoptosis has been linked to cancer development and treatment resistance. Apoptosis occurs via extrinsic or intrinsic signaling each triggered and regulated by many different molecular pathways. In recent years, the selective induction of apoptosis in tumor cells has been increasingly recognized as a promising approach for cancer therapy. A detailed understanding of the molecular pathways involved in the regulation of apoptosis is essential for developing novel effective therapeutic approaches. Apoptosis can be induced by many different approaches including activating cell surface death receptors (for example, Fas, TRAIL and TNF receptors), inhibiting cell survival signaling (such as EGFR, MAPK and PI3K), altering apoptosis threshold by modulating pro-apoptotic and anti-apoptotic members of the Bcl-2 family, down-regulating anti-apoptosis proteins (such as XIAP, survivin and c-IAP2), and using other pro-apoptotic agents. In this review, the authors reviewed the currently reported apoptosis-targeting approaches in gastrointestinal cancers.

Application of PI3K/Akt and COX-2 signal pathway blockage in treatment of gastric carcinoma

The abnormal alternation of phosphatidylinositol-3-kinase/Protein Kinase B (PI3K/PKB) and cyclooxygenase-2 (COX-2) signal pathways plays an important role in emergence and development of tumors, which also contributes to a series of biological processes and exerts a tremendous influence on treatment and prognosis of tumors. This review investigates PI3K/Akt and COX-2 signal pathways blockage and their mechanism, and provided a original direction for molecular target therapy of diverse tumors including gastric carcinoma.

Identification of CD133-positive radioresistant cells in atypical teratoid/rhabdoid tumor

Atypical teratoid/rhabdoid tumor (AT/RT) is an extremely malignant neoplasm in the central nervous system (CNS) which occurs in infancy and childhood. Recent studies suggested that CD133 could be considered a marker for brain cancer stem-like cells (CSCs). However, the role of CD133 in AT/RT has never been investigated. Herein we report the isolation of CD133-positive cells (CD133⁺), found to have the potential to differentiate into three germ layer tissues, from tissues of nine AT/RT patients. The migration/invasion/malignancy and radioresistant capabilities of CD133⁺ were significantly augmented when compared to CD133⁻. The clinical data showed that the amount of CD133⁺ in AT/RTs correlated positively with the degree of resistance to radiation therapy. Using cDNA microarray analysis, the genotoxic–response profiles of CD133⁺ and CD133⁻ irradiated with 10 Gy ionizing radiation (IR) were analyzed 0.5, 2, 6, 12 and 24 h post-IR. We then validated these microarray data and showed increased phosphorylation after IR of p-ATM, p-RAD17, and p-CHX2 as well as increased expression of BCL-2 protein in CD133⁺ compared to CD133⁻. Furthermore, we found that CD133⁺ can effectively resist IR with cisplatin- and/or TRAIL-induced apoptosis. Immunohistochemical analysis confirmed the up-regulated expression of p-ATM and BCL-2 proteins in IR-treated CD133⁺ xenotransgrafts in SCID mice but not in IR-treated CD133⁻. Importantly, the effect of IR in CD133⁺ transplanted mice can be significantly improved by a combination of BCL-2 siRNA with debromohymenialdisine, an inhibitor of checkpoint kinases. In sum, this is the first report indicating that CD133⁺ AT/RT cells demonstrate the characteristics of CSCs. The IR-resistant and anti-apoptotic properties in CD133⁺ may reflect the clinical refractory malignancy of AT/RTs and thus the activated p-ATM pathway and BCL-2 expression in CD133⁺ could be possible targets to improve future treatment of deadly diseases like AT/RT.