INO-1001, a novel inhibitor of poly(ADP-ribose) polymerase,enhances tumor response to doxorubicin

Summary Poly(ADP-ribose) synthetase inhibitor, INO-1001, is known to sensitize cells to radiation in vitro by inhibiting the repair of DNA damage. Recent evidence has suggested that PARP inhibition may also be a way of selectively targeting p53 deficient cancer cells. The present study tested INO-1001 for its in vivo effect on the chemoresponse of two p53 deficient tumors, human breast cancer MDA-MB-231 and murine mammary carcinoma MCa-K. Doxorubicin was used as the DNA damaging agent and tumor growth delay assay was used as the endpoint. Results showed that INO-1001 was highly effective in enhancing the anti-tumor effects of Doxorubicin for both MDA-MB-231 (EF = 1.88) and MCa-K (EF = 1.64). We conclude that PARP inhibitor INO-1001 has high potential for enhancing the anti-tumor effects of chemotherapy agents such as Doxorubicin against p53 deficient breast cancer.     

LncRNA XIST promotes chemoresistance of breast cancer cells to doxorubicin by sponging miR-200c-3p to upregulate ANLN

The resistance of breast cancer cells to drugs is a major obstacle to effective cancer chemotherapy. Here, we study the function mechanisms of long non-coding RNA XIST in chemoresistance of breast cancer to doxorubicin. We examined the 50% inhibitive concentration of doxorubicin to MDA-MB-231 and MDA-MB-231/ADM cells, showing that the doxorubicin resistance of MDA-MB-231/ADM cells was much higher than MDA-MB-231 cells. The gene or protein expression of XIST and ANLN were also higher in MDA-MB-231/ADM cells than that in MDA-MB-231 cells. Moreover, XIST overexpression promoted cell proliferation and inhibited apoptosis of doxorubicin-treated MDA-MB-231 cells by promoting ANLN expression. XIST silencing inhibited cell proliferation and promoted apoptosis of doxorubicin-treated MDA-MB-231/ADM cells by inhibiting ANLN expression. Luciferase reporter assay showed that XIST functioned as a competing endogenous RNA to repress miR-200c-3p, which controlled its downstream target ANLN. In conclusion, these data reveal that XIST promotes chemoresistance of breast cancer cells to doxorubicin by sponging miR-200c-3p to upregulate ANLN. This work explores the relationship between lncRNA XIST and doxorubicin resistance in breast cancer cells and highlights a novel therapeutic target for the treatment of breast cancer.     

Lipid-polymer hybrid nanoparticle with cell-distinct drug release for treatment of stemness-derived resistant tumor

Drug resistance presents one of the major causes for the failure of cancer chemotherapy.Cancer stem-like cells(CSCs),a population of self-renewal cells with high tumorigenicity and innate chemoresistance,can survive conventional chemotherapy and generate increased resistance.Here,we develop a lipid-polymer hybrid nanoparticle for co-delivery and cell-distinct release of the differentiation-inducing agent,all-trans retinoic acid and the chemotherapeutic drug,doxorubicin to overcome the CSC-associ...     

The nucleoside antagonist cordycepin causes DNA double strand breaks in breast cancer cells

The fungal drug cordycepin (3-deoxyadenosine) is known to exert anti-tumor activities, preferentially by interfering with RNA synthesis. We have investigated the effect of cordycepin on human breast epithelial cell lines, ranging from non-malignant MCF10A cells to highly de-differentiated MDA-MB-435 cancer cells. Treatment of human breast cancer cells with cordycepin caused either apoptosis or persistent cell cycle arrest that was associated with reduced clonal growth of cordycepin-treated breast cancer cells. Highly de-differentiated breast cancer cell lines, such as MDA-MB-231 and MDA-MB-435, reacted more sensitive to cordycepin than less aggressive breast cancer cell lines (MCF7, T47D) or non-malignant breast epithelial cells (MCF10A), which poorly reacted to cordycepin. In cordycepin-sensitive breast cancer cells, a marked induction of the DNA damage response (DDR), including the phosphorylation of ATM, ATR, and histone γH2AX could be observed. These data indicate that cordycepin, which was believed to cause cancer cell death by inhibition of RNA synthesis, induces DNA double strand breaks in breast cancer cells. The genotoxic effect of cordycepin on breast cancer cells indicates a new mechanism of cordycepin-induced cancer cell death, and its activity against highly undifferentiated breast cancer cells provides a new perspective of how cordycepin may be used in the treatment of advanced breast cancer.     

Frondoside A inhibits human breast cancer cell survival, migration, invasion and the growth of breast tumor xenografts

Breast cancer is a major challenge for pharmacologists to develop new drugs to improve the survival of cancer patients. Frondoside A is a triterpenoid glycoside isolated from the sea cucumber, Cucumaria frondosa. It has been demonstrated that Frondoside A inhibited the growth of pancreatic cancer cells in vitro and in vivo. We investigated the impact of Frondoside A on human breast cancer cell survival, migration and invasion in vitro, and on tumor growth in nude mice, using the human estrogen receptor-negative breast cancer cell line MDA-MB-231. The non-tumorigenic MCF10-A cell line derived from normal human mammary epithelium was used as control. Frondoside A (0.01-5 μM) decreased the viability of breast cancer cells in a concentration- and time-dependent manner, with 50%-effective concentration (EC50) of 2.5 μM at 24h. MCF10-A cells were more resistant to the cytotoxic effect of Frondoside A (EC50 superior to 5 μM at 24 h). In the MDA-MB-231 cells, Frondoside A effectively increased the sub-G1 (apoptotic) cell fraction through the activation of p53, and subsequently the caspases 9 and 3/7 cell death pathways. In addition, Frondoside A induced a concentration-dependent inhibition of MDA-MB-231 cell migration and invasion. In vivo, Frondoside A (100 μg/kg/dayi.p. for 24 days) strongly decreased the growth of MDA-MB-231 tumor xenografts in athymic mice, without manifest toxic side-effects. Moreover, we found that Frondoside A could enhance the killing of breast cancer cells induced by the chemotherapeutic agent paclitaxel. These findings identify Frondoside A as a promising novel therapeutic agent for breast cancer.     

槐耳颗粒联合DC-CIK细胞对乳腺癌MDA-MB-231干细胞体内外杀伤作用研究

目的 探究白屈菜红碱（CHE）对腺样囊性癌细胞（ACC2）生长的抑制作用及机制。方法 利用CCK8法、EdU法、Hoechst33342/PI双染色法、试剂盒法检测CHE对ACC2细胞活力、细胞增殖、细胞凋亡和活性氧（ROS）水平的影响;通过Western blotting技术检测CHE对Cleaved-Caspase 3、PARP、NF-κB、p-JNK、p-p38蛋白表达的影响;利用斑马鱼移植瘤模型检测CHE对斑马鱼体内ACC2细胞生长的抑制作用。结果 CCK-8结果显示：与对照组比较,2、3、4、5、6、7、8、9、10 μmol/L的CHE显著降低ACC2细胞的存活率（P<0.05、0.01）,且呈浓度相关性; ROS检测结果显示：与对照组比较,5、8 μmol/L的CHE导致ACC2细胞内的ROS水平显著上升（P<0.05、0.01）; EdU增殖检测结果表明：与对照组比较,5、8 μmol/L的CHE致使ACC2细胞的增殖能力显著下降（P<0.01）;Hoechst/PI染色结果显示：与对照组比较,CHE 5、8 μmol/L组ACC2细胞凋亡率显著上升（P<0.01）。抗氧化剂N-乙酰半胱氨酸（NAC）显著抑制CHE诱导的ROS水平升高、细胞凋亡增加（P<0.01）;Western blotting结果显示：2、5、8 μmol/L的CHE能够显著上调Cleaved-Caspase 3、PARP、NF-κB蛋白的表达（P<0.01）,且呈现浓度相关性,5、8 μmol/L的CHE能够显著上调p-JNK的蛋白表达（P<0.01）,8 μmol/L的CHE能够显著上调p-p38的蛋白表达（P<0.01）;NAC显著降低由CHE导致的Cleaved-Caspase 3、PARP、NF-κB、p-JNK、p-p38蛋白表达增加（P<0.01）,5、8 μmol/L CHE能够有效抑制斑马鱼体内肿瘤的生长（P<0.01）。结论 体外及斑马鱼移植瘤模型证明,CHE可以有效抑制ACC2细胞生长,其机制与提高细胞ROS水平,上调NF-κB、p-JNK、p-p38表达,从而抑制细胞增殖、诱导细胞凋亡相关。     

Anti-tumor potential of 15,16-dihydrotanshinone I against breast adenocarcinoma through inducing G1 arrest and apoptosis

Chemotherapeutic drugs are usually designed to induce cancer cell death via cell cycle arrest and/or apoptosis pathways. In this study, we used the chemical drug 15,16-dihydrotanshinone I (DHTS) to inhibit breast cancer cell proliferation and tumor growth, and investigate the underlying molecular mechanisms. Human breast cancer cell lines MCF-7 and MDA-MB-231 were both used in this study, and DHTS was found to significantly decrease cell proliferation by a dose-dependent manner in both cells. Flow cytometry indicated that DHTS induced G1 phase arrest in synchronous MCF-7 and MDA-MB-231 cells. When analyzing the expression of cell cycle-related proteins, we found that DHTS reduced cyclin D1, cyclin D3, cyclin E, and CDK4 expression, and increased CDK inhibitor p27 expression in a dose-dependent manner. In addition, DHTS inhibited the kinase activities of CDK2 and CDK4 by an immunocomplex kinase assay. In addition, DHTS also induced apoptosis in both cells through mainly mitochondrial apoptosis pathways. We found that DHTS decreased the anti-apoptotic protein Bcl-xL level and increased the loss of mitochondria membrane potential and the amount of cytochrome c released. Moreover, DHTS activated caspase-9, caspase-3, and caspase-7 and caused cell apoptosis. The fact that DHTS-induced apoptosis could be blocked by pretreating cells with pan-caspase inhibitor confirmed that it is mediated through activation of the caspase-3-dependent pathway. In a nude mice xenograft experiment, DHTS significantly inhibited the tumor growth of MDA-MB-231 cells. Taken together, these results suggest that DHTS can inhibit human breast cancer cell proliferation and tumor growth, and might have potential chemotherapeutic applications.     

Acute phorbol ester treatment inhibits thapsigargin-induced cell death in porcine aortic smooth muscle cells

Both mycelium and fruiting body of Antrodia camphorate, a traditional medicinal fungus of the family Polyporaceae in Taiwan, have been suggested to possess multiple biological functions. However, there is little information on the anticancer components and actions of mycelium of Antrodia camphorate. In the present study, the anticancer potential of synthesized maleimide derivatives, which have been isolated from mycelium of Antrodia camphorate, is examined. Comparing the cytotoxicity of two synthesized maleimide derivatives in four human cancer cell lines, camphorataimide B displayed potent efficacy. Then we investigated the impact of camphorataimide B on cell survival and cell cycle progression in vitro, and tumor growth in vivo in MDA-MB-231 breast cancer cells. Camphorataimide B decreased the cell viability and foci formation of MDA-MB-231 breast cancer cells. Further, camphorataimide B triggered apoptosis and blocked cell cycle progression of MDA-MB-231 breast cancer cells. Using immunoblotting analysis, camphorataimide B decrease the expression of cyclin-A and cyclin-B1. Moreover, we demonstrated for the first time that camphorataimide B inhibited cyclooxygenase-2 (COX-2) activity and protein expression in MDA-MB-231 cells. In nude mice study, camphorataimide B administration retarded the xenograft tumor growth of MDA-MB-231 cells. By immunohistochemical analysis, camphorataimide B decreased the expression of Ki-67 in xenograft tumor in vivo. It implied that camphorataimide B blocked cell cycle progression. Consistent with the cell culture investigation, camphorataimide B also reduced the expression of cyclin-A, cyclin-B1 and COX-2 in xenograft tumor. Thus, camphorataimide B may play a crucial role in prevention and therapy of malignant breast cancer.     

ATP chemosensitivity testing of new antitumor duplex drugs linking 3`-C-ethynylycytidine (ECyd) and 2´-deoxy-5-fluorouridine (5-FdU) in comparison to standard cytostatica and combinations thereof

Background 2′-Deoxy-5-fluorouridylyl-(5′-5′)-3′-C-ethynylcytidine [5-FdU(5′-5′)ECyd] and 3′-C-ethynylcytidinylyl-(5′->1-O)-2-O-octadecyl-sn-glycerylyl-(3-Ο−>5′)-2′-deoxy-5-fluorouridine [ECyd-lipid-5-FdU] are antitumor active duplex drugs and these heterodinucleoside phosphate analogues could be cleaved in vivo by wide-spread phosphodiesterases into different antitumor active antimetabolites. Methods We cultured breast MCF-7, MDA-MB-231 and ovarian OVCAR-29 and OAW-42 cancer cell lines and used the luminometric measuring of the ATP tumor chemosensitivity assay to assess the in vitro activity of 5-FdU(5′-5′)ECyd and ECyd-lipid-5-FdU in comparison to standard single cytostatic agents and combinations thereof currently used in anticancer therapies. To allow comparison between samples and different regimens IndexSUM was determined based on the percentage tumor cell growth inhibition at each test drug concentration. Additionally, the cytostatic efficacy of 5-FdU(5′-5′)ECyd and ECyd-lipid-5-FdU was evaluated at a minimum of five concentrations at 10 fold dilutions using 60 human tumor cell lines including ovarian and breast cancer cell lines from the National Cancer Institute (USA). Results 5-FdU(5′-5′)ECyd and ECyd-lipid-5-FdU have a high cytostatic efficacy reaching 50% tumor cell growth inhibition at concentrations ranging between nano- and micomolar. IndexSum values for broad range efficacy in MCF-7 breast cancer cells were comparable to values obtained for standard drug combinations. Higher cytostatic efficacy was observed in MDA-MB-231 cells. Conclusion The duplex drugs 5-FdU(5′-5′)ECyd and ECyd-lipid-5-FdU represent potential new chemotherapeutic drugs for breast and ovarian cancer cells which are comparable to currently used drug combinations and more potent in comparison to some monocytostatica used in cancer therapy.     

Differential effects of butyrate derivatives on human breast cancer cells grown as organotypic nodules in vitro and as xenografts in vivo.

The antiproliferative and cytodifferentiating effects of a new stable butyric derivative, monobut-3, were compared using human MDA-MB-231 breast cancer cells grown in three dimension as either in vitro tumor nodules or in vivo xenograft tumors. In in vitro tumor nodules, monobut-3 exhibited marked growth inhibitory effects consistent with the results obtained in monolayer cell cultures. Some functional cell differentiation was also detected in treated nodules. In in vivo xenografts, monobut-3 significantly decreased MDA-MB-231 tumor take but did not affect the rate of tumor growth. No difference was noted in the histological characteristics of the xenografts between untreated and treated mice. Moreover, once monobut-3 treatment was discontinued, tumor growth rapidly resumed in tumor-free animals. The decreased efficacy of monobut-3 in in vivo MDA-MB-231 xenografts as compared to in vitro tumor nodules indicates that factors related to host environment may still limit the clinical effectiveness of this compound.     

镰形棘豆总生物碱抗肿瘤活性部位的体外筛选

目的 筛选出镰形棘豆总生物碱抗肿瘤的主要活性部位.方法 将镰形棘豆生物碱粗提部位经萃取后按照极性大小分为二氯甲烷部位、乙酸乙酯部位和正丁醇部位,采用四甲基偶氮唑盐(MTT)法观察各部位对人肝癌细胞SMMC-7721、人肺癌细胞A549、人胃癌细胞MKN-45、人结肠癌细胞LOVO、人宫颈癌细胞HeLa以及人乳腺癌细胞MDA-MB-231等6种人癌细胞株增殖的影响.结果 总生物碱的正丁醇部位几乎没有抑制细胞增殖的作用,乙酸乙酯部位抑制作用比较弱,而二氯甲烷部位显示有较明显地抑制肿瘤细胞增殖的活性,且对6种细胞都有效.此外,不同的肿瘤细胞株对同一药物的敏感性也各不相同,人肺癌细胞A549和人乳腺癌细胞MDA-MB-231对药物有较高的敏感性.结论 镰形棘豆抗肿瘤的活性部位为总生物碱的二氯甲烷部位.     

Ganoderic acids suppress growth and angiogenesis by modulating the NF-kappaB signaling pathway in breast cancer cells

It has been demonstrated that ganoderma acids suppress growth, angiogenesis and invasiveness of highly invasive and metastatic breast cancer cells in vitro and vivo. However, the mechanism of action of ganoderma acids in breast cancer remains unknown. In the present study, we looked into the effect of ganoderic acid Me (GA-Me) on cellular phenotypes and tumor growth in the MDA-MB-231 breast cancer cell line. The results indicated the GA-Me inhibited nuclear factor kappaB (NF-κB) activity at 24 h in MDA-MB-231 cells. When MDAMB- 231 cells were stimulated with tumor necrosis factor-alpha (TNF-α), the inhibitory effects of GA-Me were still maintained. We demonstrated that GA-Me inhibited proliferation and invasion and induced apoptosis in MDA-MB-231 cells via suppressing the NF-κB activity. However, GA-Me did not inhibit the phosphorylation and degradation of IkappaB-α (IkB-α). GA-Me down-regulated the expression of various NF-κB-regulated genes including genes involved in cell proliferation (c-Myc and cyclin D1), anti-apoptosis (Bcl-2), invasion (MMP-9) and angiogenesis (VEGF, interleukin (IL)-6 and -8). I.P. administration of GA-Me inhibited tumor growth of MDA-MB-231 cells in vivo. Our results demonstrated that GA-Me inhibited proliferation, angiogenesis, invasion and induced apoptosis in MDA-MB-231 cells via suppressing NF-κB activity and the expression profile of its downstream genes. These findings provide evidence for a novel role of GA-Me in the prevention and treatment of breast cancer by its ability to modulate the NF-κB signaling pathway.     

Cordycepin-induced apoptosis and autophagy in breast cancer cells are independent of the estrogen receptor

Cordycepin (3-deoxyadenosine), found in Cordyceps spp., has been known to have many therapeutic effects including immunomodulatory, anti-inflammatory, antimicrobial, and anti-aging effects. Moreover, anti-tumor and anti-metastatic effects of cordycepin have been reported, but the mechanism causing cancer cell death is poorly characterized. The present study was designed to investigate whether the mechanisms of cordycepin-induced cell death were associated with estrogen receptor in breast cancer cells. Exposure of both MDA-MB-231 and MCF-7 human breast cancer cells to cordycepin resulted in dose-responsive inhibition of cell growth and reduction in cell viability. The cordycepin-induced cell death in MDA-MB-231 cells was associated with several specific features of the mitochondria-mediated apoptotic pathway, which was confirmed by DNA fragmentation, TUNEL, and biochemical assays. Cordycepin also caused a dose-dependent increase in mitochondrial translocation of Bax, triggering cytosolic release of cytochrome c and activation of caspases-9 and -3. Interestingly, MCF-7 cells showed autophagy-associated cell death, as observed by the detection of an autophagosome-specific protein and large membranous vacuole ultrastructure morphology in the cytoplasm. Cordycepin-induced autophagic cell death has applications in treating MCF-7 cells with apoptotic defects, irrespective of the ER response. Although autophagy has a survival function in tumorigenesis of some cancer cells, autophagy may be important for cordycepin-induced MCF-7 cell death. In conclusion, the results of our study demonstrate that cordycepin effectively kills MDA-MB-231 and MCF-7 human breast cancer cell lines in culture. Hence, further studies should be conducted to determine whether cordycepin will be a clinically useful, ER-independent, chemotherapeutic agent for human breast cancer.     

Different apoptotic effects of saxifragifolin C in human breast cancer cells

Breast cancer is currently the most common form of cancer affecting women. Recent studies have reported that triterpenoid saponins isolated from Androsace umbellata exhibit anti-proliferative effects in several types of cancer cells. However, the cytotoxic effect of saxifragifolin C (Saxi C) on breast cancer cells remains unclear. The purpose of this study is to evaluate the in vitro anti-tumor activity of Saxi C in human breast cancer cells. Our data indicated that MDA-MB-231 cells were more sensitive than MCF-7 cells to Saxi C treatment. In addition, Saxi C inhibited cell survival through the induction of reactive oxygen species and the caspase-dependent pathway in the MDA-MB-231 cells, whereas MCF-7 cells treated with Saxi C underwent the apoptotic cell death in a caspase-independent manner. Although Saxi C treatment resulted in the induction of activation of MAPKs in both types of human breast cancer cells, p38 MAPK and JNK, but not ERK1/2, appeared to be involved in Saxi C-induced apoptosis. Moreover, ERα-overexpressing MDA-MB-231 cells remained alive, whereas the survival of shERα-transfected MCF-7 cells decreased. Taken together, Saxi C induced apoptosis in MCF-7 cells and MDA-MB-231 cells via different regulatory mechanisms, and ERα status might be essential for regulating Saxi C-induced apoptosis in breast cancer cells. Thus, Saxi C is a potential chemotherapeutic agent in breast cancer.     

索拉非尼联合多柔比星对人乳腺癌MDA-MB-231细胞和人肺癌A549细胞抑制作用的研究

目的观察索拉非尼联合多柔比星对人乳腺癌MDA-MB-231细胞和人肺癌A549细胞的抑制作用。方法不同浓度索拉非尼联合多柔比星处理人乳腺癌MDA-MB-231细胞和人肺癌A549细胞。①以CCK-8法检测处理24、48和72 h后MDA-MB-231和A549的抑制率;②以细胞划痕试验观察受试细胞的迁移能力;③以印迹试验检测处理24 h后MDAMB-231细胞内P-ERK和Bcl-2的表达情况。结果索拉非尼联合多柔比星能显著抑制人肺癌A549细胞和人乳腺癌MDAMB-231细胞的体外增殖,且具时间依赖性;人乳腺癌MDA-MB-231细胞经不同浓度索拉非尼联合多柔比星处理24 h,P-ERK和Bcl-2蛋白的表达明显下调并呈剂量依赖性。结论索拉非尼联合多柔比星具有抑制人乳腺癌MDA-MB-231细胞和人肺癌A549细胞的增殖,诱导细胞凋亡的作用。     

Plumbagin attenuates cancer cell growth and osteoclast formation in the bone microenvironment of mice

Aim： To investigate the effects of plumbagin, a naphthoquinone derived from the medicinal plant Plumbago zeylanica, on human breast cancer cell growth and the cancer cell-induced osteolysis in the bone microenvironment of mice.
Methods： Human breast cancer cell subline MDA-MB-231SA with the ability to spread and grow in the bone was tested. The cell proliferation was determined using the CCK-8 assay. Apoptosis was detected with Annexin V/PI double-labeled flow cytometry. Red fluorescent protein-labeled MDA-MB-231SArfp cells were injected into the right tibia of female BALB/c-nu/nu mice. Three days after the inoculation, the mice were injected with plumbagin （2, 4, or 6 mg/kg, ip） 5 times per week for 7 weeks. The growth of the tumor cells was monitored using an in vivo imaging system. After the mice were sacrificed, the hind limbs were removed for radiographic and histological analyses.

Results： Plumbagin （2.5–20 μmol/L） concentration-dependently inhibited the cell viability and induced apoptosis of MDA-MB-231SA cells in vitro （the IC50 value of inhibition of cell viability was 14.7 μmol/L）. Administration of plumbagin to breast cancer bearing mice delayed the tumor growth by 2–3 weeks and reduced the tumor volume by 44%–74%. The in vivo imaging study showed that plumbagin dose-dependently inhibited MDA-MB-231SArfp cell growth in bone microenvironment. Furthermore, X-ray images and micro-CT study demonstrated that plumbagin reduced bone erosion area and prevented a decrease in bone tissue volume. Histological studies showed that plumbagin dose-dependently inhibited the breast cancer cell growth, enhanced the cell apoptosis and reduced the number of TRAcP-positive osteoclasts.

Conclusion： Plumbagin inhibits the cell growth and induces apoptosis in human breast cancer cells in mice bone microenvironment, leading to significant reduction in osteolytic lesions caused by the tumor cells.     

Berberine inhibits growth of the breast cancer cell lines MCF-7 and MDA-MB-231

The effects of berberine on the behavior of breast tumors have not yet been established. To determine whether this compound is useful in the treatment of breast cancer, we analyzed the impact of berberine on the human breast cancer cell lines MCF-7 and MDA-MB-231 cells. Berberine was added to proliferating MCF-7 and MDA-MB-231 cells in culture. Following treatment, changes in cell growth characteristics such as proliferation, cell cycle duration, and the degree of apoptosis were assayed. Following berberine treatment, a time-dependent reduction in proliferation was observed in both cell lines at differing concentrations: 20 microM for MCF-7 and 10 microM for MDA-MB-231 cells. Annexin V staining showed an increase in apoptosis in both cell lines of 31 % in MCF-7 and 12 % in MDA-MB-231 cells compared to their respective controls. In addition, 12 % of the MCF-7 cells were arrested at G0/G1, compared to 62 % of control cells. These results demonstrate that treatment with berberine inhibits growth in both MDA-MB-231 and MCF-7 cells. In addition, they show that this partly occurs through the induction of apoptosis in MDA-MB-231 cells, and through both cell cycle arrest and induction of apoptosis in MCF-7 cells. Thus, berberine may be a novel therapeutic drug for breast cancer.     

间充质干细胞来源的外泌体抑制乳腺癌细胞生长的研究

摘要： 目的 研究脐带间充质干细胞来源的外泌体 （MSCs-Exo） 对乳腺癌细胞生长的影响。方法 利用生物发光成像技术的双报告基因 （萤火虫荧光素酶-绿色荧光蛋白, Fluc-GFP） 载体, 通过慢病毒转染构建人乳腺癌MDA- MB-231细胞系 （231-Fluc-GFP）, 以便在体内可以对细胞进行实时监测。分别采用MSCs-Exo （MSCs-Exo组） 和PBS （对照组） 处理细胞, 体外实验对2组细胞进行形态学观察、 增殖、 存活、 STAT3及其下游基因表达的检测; 通过皮下注射2组细胞建立裸鼠体内乳腺癌模型, 对不同处理条件下的细胞成瘤情况进行分析。结果 体外实验结果显示 MSCs-Exo处理后乳腺癌MDA-MB-231细胞增殖受到了抑制, 在处理第3天时2组细胞数差异有统计学意义 （P＜ 0.05）; 处理后细胞存活率降低 （P＜0.01）; 外泌体处理组STAT3及其下游基因C-MYC, BCL-XL, NANOG, OCT4, SOX2 表达下降。体内实验结果显示MSCs-Exo处理组肿瘤细胞在体内的生长受到抑制。结论 脐带间充质干细胞来源的外泌体抑制乳腺癌细胞的生长。     

化疗药体外干预诱导人乳腺癌细胞产生耐药性的研究

目的研究化疗药物高浓度冲击法和低浓度干预对乳腺癌细胞MDA-MB-231多药耐药性的影响。方法采用化疗药物紫杉醇、阿霉素高浓度冲击和紫杉醇低浓度短期干预MDA-MB-231细胞,SRB法检测细胞药敏性改变;HE染色检测细胞形态;免疫细胞化学检测P-gp蛋白表达变化;RT-PCR检测MDR1基因表达。结果阿霉素高浓度冲击后细胞未存活,紫杉醇高浓度冲击后细胞能存活并最终稳定生长(MDA-MB-231/a),SRB法检测IC50发现该细胞药敏性与野生型细胞(MDA-MB-231/w)无差异;紫杉醇低浓度短期干预后(MDA-MB-231/b)SRB法检测发现该细胞对多种化疗药的IC50比野生型略有提高;免疫细胞化学显示MDA-MB-231/aP-gp表达与野生型无差异,MDA-MB-231/bP-gp表达略有提高;RT-PCR检测发现MDA-MB-231/b中MDR1基因表达高于MDA-MB-231/w。结论化疗药物高浓度冲击法无法获得MDA-MB-231的耐药细胞,低浓度短期干预可以略微提高细胞的耐药性,提示低浓度持续诱导法可以获得MDA-MB-231的耐药细胞。