A comparative in vitro study on the effect of SGLT2 inhibitors on chemosensitivity to doxorubicin in MCF-7 breast cancer cells

Cancer frequently develops resistance to the majority of chemotherapy treatments.This study aimed to examine the synergistic cytotoxic and antitumor effects of SGLT2 inhibitors,specifically Canagliflozin(CAN),Dapagliflozin(DAP),Empagliflozin(EMP),and Doxorubicin(DOX),using in vitro experimentation.The precise combination of CAN+DOX has been found to greatly enhance the cytotoxic effects of doxorubicin(DOX)in MCF-7 cells.Interestingly,it was shown that cancer cells exhibit an increased demand for glucose and ATP in order to support their growth.Notably,when these medications were combined with DOX,there was a considerable inhibition of glucose consumption,as well as reductions in intracellular ATP and lactate levels.Moreover,this effect was found to be dependent on the dosages of the drugs.In addition to effectively inhibiting the cell cycle,the combination of CAN+DOX induces substantial modifications in both cell cycle and apoptotic gene expression.This work represents the initial report on the beneficial impact of SGLT2 inhibitor medications,namely CAN,DAP,and EMP,on the responsiveness to the anticancer properties of DOX.The underlying molecular mechanisms potentially involve the suppression of the function of SGLT2.

UBE2T mediates the stemness properties of breast cancer cells through the mTOR signaling pathway

Objectives:This study aimed to reveal the role and possible mechanism of the ubiquitin-conjugating enzyme 2T(UBE2T)in the biological activities of breast cancer stem cells(BCSCs).Methods:The specific protein and gene expression were quantified by Western blotting and quantitative real-time polymerase chain reaction,the proportion of BCSCs was examined by flow cytometry,and the self-renewal and proliferation of BCSCs were verified by serial sphere formation and soft agar.Results:Increasing expression of UBE2T was drastically found in breast cancer than that in adjacent tissues.Furthermore,UBE2T overexpression significantly increased the proportion of BCSCs in breast cancer cells and promoted their self-renewal and proliferation.Silent UBE2T exhibited the opposite functions.UBE2T increased the levels of the mammalian target of rapamycin and the phosphorylated mammalian target of rapamycin.Mammalian target of rapamycin(mTOR)inhibitor rapamycin inhibited the function of UBE2T in BCSCs.Conclusion:UBE2T plays a role in BCSCs through mTOR pathway and may suggest a novel therapeutic strategy for breast cancer.

Exosome-Transmitted miR-224-5p Promotes Colorectal Cancer Cell Proliferation via Targeting ULK2 in p53-Dependent Manner

Objective To investigate the role and molecular mechanism of exosomal miR-224-5p in colorectal cancer(CRC).Methods The miR-224-5p expression in CRC patient tissues and cell-derived exosomes was measured by laser capture microdissection and qRT-PCR,respectively.Dual-luciferase reporter gene assay was used to determine the target gene of miR-224-5p.The protein expressions of p53 and unc-51 like kinase 2(ULK2)in CRC cells were detected by western blot.Flow cytometry was used to detect cell cycle and apoptosis.Cell proliferation was measured by CCK8 and EdU assay.Results The miR-224-5p expression was upregulated in CRC tissues and increased progressively with the rise of CRC stage.CRC cells secreted extracellular miR-224-5p mainly in an exosome-dependent manner,and then miR-224-5p could be transferred to surrounding tumor cells to regulate cell proliferation in the form of autocrine or paracrine.Moreover,ULK2 was characterized as a direct target of miR-224-5p and was downregulated in CRC tissues.Interestingly,ULK2 inhibited CRC cell proliferation in a p53-dependent manner.Furthermore,exosome-derived miR-224-5p partially reversed the proliferation regulation of ULK2 on CRC cells.Conclusion Our findings demonstrate that exosome-transmitted miR-224-5p promotes p53-dependent cell proliferation by targeting ULK2 in CRC,which may offer promising targets for CRC prevention and therapy.

Prostaglandin D2 regulation of autophagy affects stemness of gastric cancer stem cells

Objective:To explore the effect and mechanism of prostaglandins D2(PGD2)on the stemness of gastric cancer stem cells(GCSCs).Methods:7901-GCSCs were enriched by serum-free culture method;then the positivity rate of CD44,a stemness marker,was detected by flow cytometry in serum-free cultured 7901-GCSCs;the sphere-forming ability was detected by the sphere-forming assay after stimulation with different concentrations of PGD2(2.5,5,10)μg/mL,and the expression of stemness-related indicators(OCT4,CD44)and autophagyrelated proteins(LC3,Beclin-1)after PGD2 stimulation was detected by the western blot assay in different concentrations.The expression of stemness-related indexes(OCT4,CD44)and autophagy-related proteins(LC3,Beclin-1)were detected by Western blot assay after stimulation with different concentrations of PGD2.The expression of autophagy-related proteins after stimulation with different concentrations of CQ(2.5,5,10)μM was detected by Western blot experiment.The protein expression of autophagy-related proteins(LC3,Beclin-1)and stemness-related indexes(OCT4,CD44)was detected by Western blot experiment after PGD2 as well as PGD2+CQ treatment.Results:Flow cytometry results showed that the expression of CD44 positivity was increased in serum-free cultured 7901-GCSCs compared with gastric cancer cells SGC-7901(P<0.05),which fulfilled the needs of subsequent experiments.The results of stem cell spheroid formation assay showed that the spheroid formation ability of 7901-GCSCs in the PGD2 group was significantly weakened compared with that of the DMSO group(P<0.05).Western blot results showed that the protein expression of stemness-related indexes(OCT4,CD44)was down-regulated in the 7901-GCSCs in the PGD2 group compared with that of the DMSO group(P<0.05),and the expression of autophagy-related proteins(LC3,Beclin-1)expression increased(P<0.05).Compared with the DMSO group,the expression of autophagy-related proteins(LC3,Beclin-1)was decreased in the CQ group(P<0.05).Western blot results also showed that the expression of cellular autophagy-related proteins and stemness-related indexes in the PGD2+CQ group was not significantly changed compared with that of the DMSO group(ns:the difference was not significant),suggesting that the CQ could block the effect of PGD2 on the expression of stemness markers in 7901-GCSCs.7901-GCSCs stemness inhibition.Conclusion:PGD2 may affect the stemness of 7901-GCSCs by regulating autophagy.

ECRG2 enhances the anti-cancer effects of cisplatin in cisplatin-resistant esophageal cancer cells via upregulation of p53 and downregulation of PNCA

AIM To explore the anti-tumor effects of esophageal cancerrelated gene 2(ECRG2) in combination with cisplatin(DDP) in DDP-resistant esophageal cancer cells(EC9706/DDP).METHODS A drug-resistant cell model was established, with EC9706/DDP cells being treated with ECRG2 and/or DDP. Cell viability was examined by MTT assay. The rate of cell apoptosis was determined by flow cytometry. The mR NA expression levels of proliferating cell nuclear antigen(PCNA), metallothionein(MT), and p53 were determined by RT-PCR and PCNA, while MT and p53 protein expression levels were determined by western blotting.RESULTS The anti-proliferative effect of ECRG2 in combination with DDP was superior when compared to ECRG2 or DDP alone. The inhibition rate for the combination reached its peak(51.33%) at 96 h. The early apoptotic rates of the control, ECRG2 alone, DDP alone, and ECRG2 plus DDP groups were 5.71% ± 0.27%, 12.68% ± 0.61%, 14.15% ± 0.87%, and 27.96% ±0.36%, respectively. Although all treatment groups were significantly different from the control group(P < 0.05), the combination treatment of ECRG2 plus DDP performed significantly better when compared to either ECRG2 or DDP alone(P < 0.05). The combination of ECRG2 and DDP significantly upregulated p53 m RNA and protein levels and downregulated PCNA m RNA and protein levels compared to ECRG2 or DDP alone(P < 0.05). However, no changes were seen in the expression of MT mR NA or protein.CONCLUSION ECRG2 in combination with DDP can inhibit viability and induce apoptosis in esophageal cancer DDP-resistant cells, possibly via upregulation of p53 expression and downregulation of PCNA expression. These findings suggest that the combination of ECRG2 and DDP may be a promising strategy for the clinical treatment of esophageal cancers that are resistant to DDP.

Effect of silencing Bcl-2 expression by small interfering RNA on radiosensitivity of gastric cancer BGC823 cells

Objective:To explore the influence of silencing Bcl-2 expression by small interfering RNA（siRNA） on Bcl-2 protein expression,cell apoptosis rale and radiosensilivity of gastric cancer BCC823 cells.Methods:siRNA segment for Bcl-2 gene was designed and synthesized,then was induced into gastric cancer BGC 823 cells by liposome transfection.Bcl-2 protein expression was detected by Western Blotting.After X radiation,flow cytometry and clone forming assay were used to determine the effects of RNA interference on BGC823 cell apoptosis rate and radiosensitivity. Result:After the transfection of Bcl-2 siRNA,the positive expression rate of Bcl-2 protein in BGC823 cells was（35.45±2.35）%.Compared with the control group and negative siRNA transfection group,the rate was significantly decreased（P【0.01）.The apoptosis rate of BGC823-RNAi cell was（10.81±0.91）%,which was significantly higher than the control group and negative siRNA transfection group（P【0.01）.After 48h X radiation,the apoptosis rate of BGC823-RNAi was（28.91±1.40）%,which was significantly higher than the control group and the group without radiation （P【0.01）.During clone forming assay D0,D4 and SF2 values in Bcl-2 siRNA1 transfection group were all lower than those in the control group.The radiosensitivity ratio was 1.28（the ratio of D0） and 1.60（the ratio of D4）.Conclusions:Specific siRNA of Bcl-2 gene can effectively inhibit the expression of Bcl-2 gene,enhance the radiosensitivity and apoptosis of gastric cancer BGC823 cells,having good clinical application perspective.

NIMA related kinase 2 promotes gastric cancer cell proliferation via ERK/MAPK signaling

BACKGROUND NIMA related kinase 2(NEK2) is closely related to mitosis, and it is currently considered to be over-expressed frequently in many poorly prognostic cancers.However, the effect of the up-regulated NEK2 on cellular signaling in tumors,such as gastric cancer(GC), is con-fusing.AIM To determine the role of the up-regulation of NEK2 in GC.METHODS To investigate the pathological significance of NEK2 in GC, the expression pattern of NEK2 in GC was investigated based on the 'Oncomain' database and compared between 30 pairs of cancer samples and adjacent tissues. The coexpression of NEK2 and ERK in GC was analyzed using The Cancer Genome Atlas(TCGA) database and confirmed in clinical samples by quantitative realtime PCR(qRT-PCR), and the survival curve was also plotted. Western blot or qRT-PCR was used to analyze the effect of NEK2 on the phosphorylation levels of ERK and c-JUN in two GC cell lines(BGC823 and SGC7901) with NEK2 overexpression, and the expression of the downstream effector cyclin D1.Furthermore, CCK8, EdU incorporation assay, and flow cytometry were used to detect the proliferative ability of BGC823 and SGC7901 cells with stably silenced ERK.RESULTS NEK2 was significantly up-regulated in human GC tissues. ERK was significantly associated with NEK2 expression in human clinical specimens, and combined overexpression of NEK2 and ERK potentially forecasted a poor prognosis andsurvival in GC patients. NEK2 knockdown in GC cells inhibited ERK and c-JUN phosphory-lation and reduced the transcription of cyclin D1. More interestingly,NEK2 can rescue the inhibition of cellular viability, proliferation, and cell cycle progression due to ERK knockdown.CONCLUSION Our results indicate that NEK2 plays a carcinogenic role in the malignant proliferation of GC cells via the ERK/MAPK signaling, which may be important for treatment and improving patient survival.

Effects of ginsenoside Rh2 on growth and migration of pancreatic cancer cells

AIM:To investigate the effects of ginsenoside Rh2 on the human pancreatic cancer cell line Bxpc-3.METHODS:The human pancreatic cancer cell line Bxpc-3 was cultured in vitro and treated with or without ginsenoside Rh2.Growth rates for Bxpc-3 cells were assessed by methyl thiazolyl tetrazolium(MTT) and colony formation assays.Cell cycle changes were analyzed by flow cytometry.Apoptosis was measured by flow cytometry and Hoechst 33258 fluorescence staining.A scratch assay and a Matrigel invasion assay were used to detect cell migration and invasion.Expression of Bax,Bcl-2,survivin,cyclin D1,matrix metalloproteinase(MMP)-2,MMP-9,cleaved caspase-3,caspase-8,and caspase-9 mRNA were determined by reverse transcriptase-polymerase chain reaction(RT-PCR).Bax,Bcl-2,survivin,cyclin D1,cleaved caspase-3,caspase-8 and caspase-9 protein levels were examined by western blotting.Expression of MMP-2 and MMP-9 proteins in culture supernatants were determined by enzymelinked immunosorbent assay(ELISA).RESULTS:Rh2 significantly inhibited Bxpc-3 cell proliferation in a dose-and time-dependent manner,as evaluated by the MTT(P < 0.05) and colony formation assays(P < 0.05).Compared to the control group,Rh2 significantly increased the percentage of Bxpc-3 cells in the G 0 /G 1 phase from 43.32% ± 2.17% to 71.32% ± 1.16%,which was accompanied by a decrease in S phase(from 50.86% ± 1.29% to 28.48% ± 1.18%) and G 2 /M phase(from 5.81% ± 1.19% to 0.20% ± 0.05%) in a dose-dependent manner(P < 0.05),suggesting that Rh2 arrested cell cycle progression at the G 0 /G 1 phase,as measured by flow cytometry.Compared to the control group,cells treated with Rh2 showed significantly higher apoptosis ratios in a dosedependent manner(percentage of early apoptotic cells:from 5.29% ± 2.28% to 38.90% ± 3.42%(F = 56.20,P < 0.05);percentage of late apoptotic cells:from 4.58% ± 1.42% to 36.32% ± 2.73%(F = 86.70,P < 0.05).Rh2 inhibited Bxpc-3 cell migration and invasion,as detected by scratch wound healing assay and Matrigel invasion assay [percentages of scratch wound healing for 12 h,24 h and 48 h(control vs experimental group):37.3% ± 4.8%vs 18.30% ± 1.65%,58.7% ± 3.5% vs 38.00% ± 4.09% and 93.83% ± 4.65% vs 65.50% ± 4.09%,respectively;t = 6.489,t = 6.656 and t = 7.926,respectively,P < 0.05;the number of cells invading at various concentrations(0 μmol/L,35 μmol/L,45 μmol/L and 55 μmol/L):81.10 ± 9.55,46.40 ± 6.95,24.70 ± 6.88 and 8.70 ± 3.34,respectively(F = 502.713,P < 0.05)].RT-PCR,western blotting or ELISA showed that mRNA and protein expression of Bax,cleaved caspase-3 and caspase-9 were upregulated(P < 0.05),while mRNA and protein expression of Bcl-2,survivin,cyclin D1,MMP-2 and MMP-9 were downregulated(P < 0.05).CONCLUSION:Ginsenoside Rh2 inhibits proliferation,migration and invasion and induces apoptosis of the human pancreatic cancer cell line Bxpc-3.

CYP24A1 inhibition facilitates the anti-tumor effect of vitamin D3 on colorectal cancer cells

AIM:The effects of vitamin D3 have been investigated on various tumors, including colorectal cancer (CRC). 25-hydroxyvitamin-D3-24-hydroxylase (CYP24A1), the enzyme that inactivates the active vitamin D3 metabolite 1,25-dihydroxyvitamin D3 (1,25-D3), is considered to be the main enzyme determining the biological halflife of 1,25-D3. During colorectal carcinogenesis, the expression and concentration of CYP24A1 increases significantly, suggesting that this phenomenon could be responsible for the proposed efficacy of 1,25-D3 in the treatment of CRC. The aim of this study was to investigate the anti-tumor effects of vitamin D3 on the human CRC cell line Caco-2 after inhibition of the cytochrome P450 component of CYP24A1 activity. METHODS:We examined the expression of CYP24A1 mRNA and the effects of 1,25-D3 on the cell line Caco-2 after inhibition of CYP24A1. Cell viability and proliferation were determined by means of sulforhodamine-B staining and bromodeoxyuridine incorporation, respectively, while cytotoxicity was estimated via the lactate dehydrogenase content of the cell culture supernatant. CYP24A1 expression was measured by realtime reverse transcription polymerase chain reaction. A number of tetralone compounds were synthesized to investigate their CP24A1 inhibitory activity. RESULTS:In response to 1,25-D3, CYP24A1 mRNA expression was enhanced significantly, in a time- and dose-dependent manner. Caco-2 cell viability and proliferation were not influenced by the administration of 1,25-D3 alone, but were markedly reduced by coadministration of 1,25-D3 and KD-35, a CYP24A1-inhibiting tetralone. Our data suggest that the mechanism of action of co-administered KD-35 and 1,25-D3 does not involve a direct cytotoxic effect, but rather the inhibition of cell proliferation. CONCLUSION:These findings demonstrate that the selective inhibition of CYP24A1 by compounds such as KD-35 may be a new approach for enhancement of the anti-tumor effect of 1,25-D3 on CRC.

The PI3K/Akt/GSK-3β/ROS/eIF2B pathway promotes breast cancer growth and metastasis via suppression of NK cell cytotoxicity and tumor cell susceptibility

Objective: To examine the effect of pSer9-GSK-3β on breast cancer and to determine whether the underlying metabolic and immunological mechanism is associated with ROS/eIF2B and natural killer(NK) cells.Methods: We employed TWS119 to inactivate GSK-3β by phosphorylating Ser9 and explored its effect on breast cancer and NK cells. The expression of GSK-3β, natural killer group 2 member D(NKG2D) ligands, eIF2B was quantified by PCR and Western blot. We measured intracellular reactive oxygen species(ROS) and mitochondrial ROS using DCFH-DA and MitoSOX^(TM) probe,respectively, and conducted quantitative analysis of cellular respiration on 4T1 cells with mitochondrial respiratory chain complex Ⅰ/Ⅲ kits.Results: Our investigation revealed that TWS119 downregulated NKG2D ligands(H60 a and Rae1), suppressed the cytotoxicity of NK cells, and promoted the migration of 4T1 murine breast cancer cells. Nevertheless, LY290042, which attenuates p-GSK-3β formation by inhibiting the PI3K/Akt pathway, reversed these effects. We also found that higher expression of p Ser9-GSK-3β induced higher levels of ROS, and observed that abnormality of mitochondrial respiratory chain complex Ⅰ/Ⅲ function induced the dysfunction of GSK-3β-induced electron transport chain, naturally disturbing the ROS level. In addition, the expression of NOX3 and NOX4 was significantly up-regulated, which affected the generation of ROS and associated with the metastasis of breast cancer. Furthermore, we found that the expression of pSer535-eIF2B promoted the expression of NKG2D ligands(Mult-1 and Rae1) following by expression of pSer9-GSK-3β and generation of ROS.Conclusions: The PI3K/Akt/GSK-3β/ROS/eIF2B pathway could regulate NK cell activity and sensitivity of tumor cells to NK cells,which resulted in breast cancer growth and lung metastasis. Thus, GSK-3β is a promising target of anti-tumor therapy.

Sox2 enhances the tumorigenicity and chemoresistance of cancer stem-like cells derived from gastric cancer

Gastric cancer stem-like cells（GCSCs） have been identified to possess the ability of self-renewal and tumor initi-ation.However,the mechanisms involved remain largely unknown.Here,we isolated and characterized the GCSCs by side population（SP） sorting procedure and cultured sphere cells（SC） from human gastric cancer cell lines SGC-7901,BGC-823,MGC-803,HGC-27 and MKN-28.The sorting and culture assay revealed that SP cells proliferated in an asymmetric division manner.In addition,SP cells exhibited a higher potential of spheroid colony formation and greater drug resistance than non-SP cells（NSP）.Moreover,the SC were found with enhanced capabilities of drug resistance in vitro and tumorigenicity in vivo.Sox2 mRNA and protein was highly and significantly overex-pressed in the SP cells and SC.Importantly,downregulation of Sox2 with siRNA obviously reduced spheroid colony formation and doxorubicin efflux,as well as increased apoptosis rate in sphere cells in vitro and suppressed tumori-genicity in vivo.These results suggest that both SP cells and cultured SC enrich with GCSCs and that Sox2 plays a pivotal role in sustaining stem cell properties and might be a potential target for gastric cancer therapy.

Relationship between genetic polymorphisms of metabolizing enzymes CYP2E1, GSTM1 and Kazakh's esophageal squamous cell cancer in Xinjiang, China

AIM: To analyze the relationship between genetic polymorphisms of metabolizing enzymes CYP2E1, GSTM1 andKazakh's esophageal squamous cell cancer in China.METHODS: The genotypes of cytochromes P450 (CYP) 2E1 and glutathione S-transferase (GST) M1 were investigated by polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) following PCR in 104 Kazakh's patients with esophageal cancer (EC) and 104 non-cancer controls.RESULTS: The frequency of CYP2E1 c1/c1 genotype was significantly higher in patients with cancer (77.9%) thanin control subjects (24.0%) (P＜0.05; OR, 11.13; 95%CI,5.84-21.22). The difference of GSTM1 null was significantly more frequent in the cancer (34.6%) vsthe control group (3.8%) (P＜0.05; OR, 13.24; 95%CI, 4.50-38.89). On the other hand, the combination of GSTM1 presence and CYP2E1 c1/c1 genotypes increased the risk for cancer (P＜0.05;OR, 13.42; 95%CI, 6.29-28.3).CONCLUSION: The CYP2E1 c1/c1, GSTM1 deletion genotypes are genetically susceptible biomarkers for ESCC in Kazakh population. Individuals with allele c1 of RsaI polymorphic locus for CYP2E1 may increase the risk of ESCC. Moreover, CYP2E1 wild type (c1/c1) increased thesusceptibility to ESCC risk in Kazakh individuals with GSTM1 presence genotype.

ANGPTL2 expression in gastric cancer tissues and cells and its biological behavior

AIM To explore expression of angiopoietin-like protein 2(ANGpT L2) and its effect on biological behavior such as proliferation and invasiveness in gastric cancer. METHODS Western blotting was used to detect expression of ANGp TL2 in 60 human normal gastric tissues, 60 human gastric cancer tissues and gastric cell lines including GES-1, N87, SGC7901, BGC823 and pA MC82. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) and Transwell assay were used to detect the proliferation and invasive ability of gastric cancer cells. RESULTS Compared to normal tissues, ANGp TL2 protein levels were significantly upregulated in gastric tissues, and this level was closely correlated with gastric tumor grade, clinical stage and lymph node metastasis. Compared to GES-1 cells, ANGpT L2 mR NA and protein levels were significantly increased in gastric cancer cells including N87, SGC7901, BGC823 and p AMC82. The expression of ANGpT L2 in highly malignant gastric cancer cell lines BGC823 and pA MC82 was significantly higher than in low malignancy gastric cancer cell lines N87 and SGC7901. MTT and Transwell experiments indicated that the proliferation rate and invasive ability of stable overexpressed gastric cancer cells was faster than in cells transfected with Lv-NC and blank controlcells, and the invasive ability of stable overexpressed gastric cancer cells was higher than that of cells transfected with Lv-NC and blank control cells.CONCLUSION ANGp TL2 contributed to proliferation and invasion of gastric cancer cells. In clinical treatment, ANGpT L2 may become a new target for treatment of gastric cancer.

Colon cancer-associated B2 Escherichia coli colonize gut mucosa and promote cell proliferation

AIM: To provide further insight into the characterization of mucosa-associated Escherichia coli (E. coli) isolated from the colonic mucosa of cancer patients.

Molecular analysis and anticancer properties of two identified isolates,Fusarium solani and Emericella nidulans isolated from Wady El-Natron soil in Egypt against Caco-2(ATCC) cell line

Objective:To characterize,identify and investigate the anticancer properties of two new soil fungal isolates,Emericella nidulansand Fusarium solani isolated from Wady El-Natron in Egypt against colon cancer Caco-2(ATCCj cell line.Methods:Soil sample was cultured and two strains were chosen for morphological and phenotypical characterization.Partial sequences of the 18s rRNA gene and the internal transcribed spacer region ITS of the two isolates were amplified by PCR.Phylogenetic tree construction and analysis of the resulted multiple sequences from the two fugal isolates were also carried out.In vitro anticancer activity of the two strains was done against colon Caco-2 cancer cell line.Reverse transcription — PCR was carried out to detect level of expression of p53 in Caco-2 cell line.Results:HF.I displayed morphological and genotypic characteristics most similar to that of Fusarium solani while HF.2 was most similar to Emericella nidulans with high similarity of 99%and 97%respectively.The multiple sequence alignment of the two fungal isolates showed that,the maximum identical conserved domains in the 18s rRNA genes were identified with the nucleotide regions of Slst to 399th base pairs,88th to 525th base pairs respectively.While those in the ITS genes were identified with the nucleotide regions of 88th to 463rd and Slst to 274th.The two isolates showed IC<sub>50 value with（6.24±5.21） and（9.84±0.36） μ g/mL) concentrations respectively at 28h.Reverse transcription- PCR indicated that these cells showed high level of expression for p53 mRNA.Conclusions:The morphology and molecular analysis identified HF.1 and HF.2 to be Fusarium solani and Emericella nidulans;new isolates of anticancer producing fungi from Wady El-Natroon city in Egypt.Treatment with the two isolates caused P53 expression in Caco-2 cell line.These two isolates can be used as an anticancer agents.

Prevalence and clinical significance of pathogenic germline BRCA1/2 mutations in Chinese non-small cell lung cancer patients

Objective: Germline alterations in the breast cancer susceptibility genes type 1 and 2, BRCA1 and BRCA2, predispose individuals to hereditary cancers, including breast, ovarian, prostate, pancreatic, and stomach cancers.Accumulating evidence suggests inherited genetic susceptibility to lung cancer.The present study aimed to survey the prevalence of pathogenic germline BRCA mutations(gBRCAm) and explore the potential association between gBRCAm and disease onset in Chinese advanced non-small cell lung cancer(NSCLC) patients.Methods: A total of 6,220 NSCLC patients were screened using capture-based ultra-deep targeted sequencing to identify patients harboring germline BRCA1/2 mutations.Results: Out of the 6,220 patients screened, 1.03%(64/6,220) of the patients harbored the pathogenic gB RCAm, with BRCA2 mutations being the most predominant mutations(49/64, 76.5%).Patients who developed NSCLC before 50 years of age were more likely to carry gBRCAm(P = 0.036).Among the patients harboring classic lung cancer driver mutations, those with concurrent gBRCAm were significantly younger than those harboring the wild-type gBRCA(P = 0.029).By contrast, the age of patients with or without concurrent gBRCAm was comparable to those of patients without the driver mutations(P = 0.972).In addition, we identified EGFR-mutant patients with concurrent gBRCAm who showed comparable progression-free survival but significantly longer overall survival(P = 0.002) compared to EGFR-mutant patients with wild-type germline BRCA.Conclusions: Overall, our study is the largest survey of the prevalence of pathogenic gBRCAm in advanced Chinese NSCLC patients.Results suggested a lack of association between germline BRCA status and treatment outcome of EGFR-TKI.In addition,results showed a positive correlation between pathogenic gB RCAm and an early onset of NSCLC.

Incomplete radiofrequency ablation promotes the development of CD133+cancer stem cells in hepatocellular carcinoma cell line HepG2 via inducing SOX9 expression

Background: Cancer stem cells(CSCs) accelerate the growth of hepatocellular carcinoma(HCC) residual after incomplete radiofrequency ablation(In-RFA). The present study aimed to detect the effects of In-RFA on stemness transcription factors(STFs) expression which are important for the production and function of CSCs, and to find which STFs promote HCC stemness after In-RFA. Methods: HepG2 cells were used for in vitro and in vivo studies. Flow cytometry and sphere-formation assays were used to detect the level and function of CD133~+ CSCs in the models. PCR array and ELISA were applied to analyze the altered expression of 84 STFs in CD133~+ CSCs in two models. Specific lentiviral shRNA was used to knockdown STFs expression, followed by detecting In-RFA’s effects on the levels and function of CD133~+ CSCs. Results: In-RFA was identified to induce CD133~+ CSCs and increase their tumorigenesis ability in vitro and in vivo. The mRNA levels of 84 STFs in CD133~+ CSCs were detected by PCR array, showing that 15 and 22 STFs were up-regulated in two models, respectively. Meanwhile, the mRNA levels of seven common STFs were up-regulated in both models. ELISA assay demonstrated that only the protein of sex determining region Y-box 9(SOX9) was up-regulated in both models, the protein levels of the other 6 common STFs did not increase in both models. Finally, SOX9 was identified to play an important role in inducing, maintaining stemness and promoting tumorigenesis ability of CD133~+ CSCs in both models. Conclusion: In-RFA-induced SOX9 stimulates CD133~+ CSCs proliferation and increases their tumorigenesis ability, suggesting that SOX9 may be a good target for HCC treatment.

HIF-2α regulates CD44 to promote cancer stem cell activation in triple-negative breast cancer via PI3K/AKT/mTOR signaling

BACKGROUND Breast cancer is a common malignant tumor that seriously threatens women’s health.Breast cancer stem cell(CSC)-like cell population may be the main factor for breast cancer metastasis.Therefore,targeted therapy for CSCs has great potential significance.Hypoxia-inducible factor is a transcription factor widely expressed in tumors.Studies have shown that down-regulation of the hypoxia signaling pathway inhibits tumor stem cell self-renewal and increases the sensitivity of stem cells to radiotherapy and chemotherapy mediated by hypoxiainducible factor-2α(HIF-2α).However,the specific mechanism remains unclear and further research is necessary.AIM To investigate the effect of HIF-2αdown-regulation on stem cell markers,microsphere formation,and apoptosis in breast cancer cell line MDA-MB-231 under hypoxia and its possible mechanism.METHODS Immunohistochemistry was used to detect the expression of HIF-2αand CD44 in triple-negative breast cancer(TNBC)and non-TNBC tissues.Double-labeling immunofluorescence was applied to detect the co-expression of HIF-2αand CD44 in MDA-MB-231 cells and MCF-7 cells.HIF-2αwas silenced by RNA interference,and the expression of CD44 and transfection efficiency were detected by real-time fluorescent quantitative PCR.Further,flow cytometry,TdT-mediated X-dUTP nick end labeling,and mammosphere formation assays were used to evaluate the effect of HIF-2αon CSCs and apoptosis.The possible mechanisms were analyzed by Western blot.RESULTS The results of immunohistochemistry showed that HIF-2αwas highly expressed in both TNBC and non-TNBC,while the expression of CD44 in different molecular types of breast cancer cells was different.In in vitro experiments,it was found that HIF-2αand CD44 were expressed almost in the same cell.Compared with hypoxia+negative-sequence control,HIF-2αsmall interfering ribonucleic acid transfection can lower the expression of HIF-2αand CD44 mRNA(P<0.05),increase the percentage of apoptotic cells(P<0.05),and resulted in a reduction of CD44+/CD24−population(P<0.05)and mammosphere formation(P<0.05)in hypoxic MDA-MB-231 cells.Western blot analysis revealed that phosphorylated protein-serine-threonine kinase(p-AKT)and phosphorylated mammalian target of rapamycin(p-mTOR)levels in MDA-MB-231 decreased significantly after HIF-2αsilencing(P<0.05).CONCLUSION Down-regulation of HIF-2αexpression can inhibit the stemness of human breast cancer MDA-MB-231 cells and promote apoptosis,and its mechanism may be related to the CD44/phosphoinosmde-3-kinase/AKT/mTOR signaling pathway.

Effect of silencing of high mobility group A2 gene on gastric cancer MKN-45 cells

AIM:To investigate the effect of high mobility group A2(HMGA2) gene silencing on gastric cancer MKN-45 cells in vitro.METHODS:HMGA2 short hairpin RNA(shRNA) expression plasmids were constructed,including a pair of random scrambled sequences.Human gastric cancer cell line MKN-45 cells were divided into three groups:blank control group(non-transfected cells),transfected group(cells transfected with HMGA2 shRNA recombinant plasmid) and scrambled sequence group(transfected with random scrambled plasmid).Cells were transfected with HMGA2 shRNA recombinant plasmids and scrambled plasmid in vitro,and the cells transfection efficiency was assayed by fluorescence microscopy.The HMGA2 messenger RNA(mRNA) expression was detected by reverse transcription polymerase chain reaction,gastric cancer cells apoptosis was detected by flow cytometry,cell proliferation was detected by methyl thiazol tetrazolium,and the protein expression of phosphatidylinositol 3-kinase(PI3K),protein kinase B(Akt),P27,caspase-9 and B-cell leukemia/lymphoma-2(Bcl-2) were analyzed by Western blotting.RESULTS:Compared with the blank control group and the scrambled sequence group,the levels of HMGA2 mRNA and protein expression in the transfected group were significantly reduced(P < 0.05).The relative HMGA2 mRNA expression levels of the blank control group,transfected group and scrambled sequence group were 0.674 ± 0.129,0.374 ± 0.048 and 0.689 ± 0.124,respectively.The relative HMGA2 protein expression levels of the blank control group,transfected group and scrambled sequence group were 0.554 ± 0.082,0.113 ± 0.032 and 0.484 ± 0.123,respectively.Moreover,transfection with the scrambled sequence had no effect on the expression of HMGA2.After being transfected with shRNA for 24,48 and 72 h,the cell apoptotic rates of the transfected group were 21.65% ± 0.28%,39.98% ± 1.82% and 24.51% ± 0.93%,respectively,which significantly higher than those of blank control group(4.72% ± 1.34%,5.83% ± 0.13% and 5.22% ± 1.07%) and scrambled sequence group(4.28% ± 1.33%,7.87% ± 1.43% and 6.71% ± 0.92%).After 24,48 and 72 h,the cell proliferation inhibition rates in the transfected group were 31.57% ± 1.17%,39.45% ± 2.07% and 37.56% ± 2.32%,respectively;the most obvious cell proliferation inhibition appeared at 48 h after transfection.Compared with the blank control group and scrambled sequence group,after transfection of shRNA for 72 h,the protein expression levels of PI3K(0.042 ± 0.005 vs 0.069 ± 0.003,0.067 ± 0.05),Akt(0.248 ± 0.004 vs 0.489 ± 0.006,0.496 ± 0.104) and Bcl-2(0.295 ± 0.084 vs 0.592 ± 0.072,0.594 ± 0.109) were significantly reduced.The protein expression levels of P27(0.151 ± 0.010 vs 0.068± 0.014,0.060 ± 0.013) and caspase-9(0.136 ± 0.042 vs 0.075 ± 0.010,0.073 ± 0.072) were significantly upregulated.CONCLUSION:HMGA2 shRNA gene silencing induces apoptosis and suppresses proliferation of MKN-45 cells.

PADI3 induces cell cycle arrest via the Sirt2/AKT/p21 pathway and acts as a tumor suppressor gene in colon cancer

Objective:As a member of the peptidyl arginine deiminase(PAD)family,PADI3 is weakly expressed in colon cancer tissues and highly expressed in adjacent colon cancer tissues.However,the role of PADI3 in colon cancer is unclear.In this study,we investigated the function and molecular mechanism of PADI3 in colon cancer tumorigenesis.Methods:Western blot and real-time PCR were used to detect the expression levels of several genes.CCK-8,flow cytometry(FCM)and colony formation assays were used to examine cell proliferation,the cell cycle and colony formation ability.RNAsequencing analysis was used to study the molecular mechanism of PADI3 in tumorigenesis.A truncation mutation experiment was performed to determine the key functional domain of PADI3.Results:PADI3 overexpression inhibited cell proliferation and colony formation and led to G1 phase arrest in both HCT116(originating from primary colon cancer)and LoVo(originating from metastatic tumor nodules of colon cancer)cells.PADI3-expressing HCT116 cells had a lower tumor formation rate and produced smaller tumors than control cells.PADI3 significantly decreased Sirtuin2(Sirt2)and Snail expression and AKT phosphorylation and increased p21 expression,and Sirt2 overexpression partly reversed the effects induced by PADI3 overexpression.Immunocytochemistry showed that PADI3 is mainly localized in the cytoplasm.Truncation mutation experiments showed that the C-domain is the key domain involved in the antitumor activity of PADI3.Conclusions:PADI3 suppresses Snail expression and AKT phosphorylation and promotes p21 expression by downregulating Sirt2 expression in the cytoplasm,and the C-domain is the key domain for its antitumor activity.