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1.
We have here examined ionizing radiation (IR)-induced apoptotic signaling in one IR-sensitive small cell lung carcinoma (SCLC) and one resistant non-small cell lung carcinoma (NSCLC) cell line, both harboring mutant p53. In the sensitive SCLC cell line, IR induced conformational modulation of Bak and Bax, mitochondrial depolarization, and nuclear fragmentation. These events were not observed in the IR-resistant NSCLC cell line. However, in the same cells, cisplatin, a DNA-damaging drug, induced Bak and Bax modulation, mitochondrial depolarization, and nuclear fragmentation. Pre-mitochondrial signaling events were examined in order to further characterize the differing IR response. In the SCLC cell line, IR-induced apoptotic signaling was found to involve a MEKK1-related pathway and activation of the stress-activated kinases JNK and p38. In comparison, the NSCLC cell line had higher basal levels of activity of JNK and p38, and IR treatment did not further activate these kinases. However, NSCLC cells were sensitive to Bak modulation and apoptosis induced by a kinase-active mutant of MEKK1. Together, the results delineate a mechanism of IR resistance in NSCLC cells and indicate that IR and cisplatin induce Bak modulation and apoptosis via different pathways.  相似文献   

2.
The effect of the active capacitating factor secreted from oviduct epithelial cell monolayers (OECM) in different environments on in vitro fertilization was evaluated. Capacitation was determined as the ability of sperm to fertilize bovine oocytes in vitro. When the mTALP was supplemented with glucose during conditioning, the sperm penetration rate was significantly reduced (P ≤ 0.05) compared to the control (7% ± 1 vs. 30% ± 4). The percentages of sperm penetrated oocytes were higher following insemination in the OECM-conditioned medium derived from the early stage (48% ± 7) of the estrous cycle than in the OECM-conditioned medium derived from either mid (35% ± 2) or late stages (28% ± 3) of the estrous cycle. When the medium was supplemented with 0.1 or 0.5 μg/ml estradiol-17β during medium conditioning, sperm penetration rates increased (P ≤ 0.05) compared to the control group (55% ± 4 vs. 40% ± 3 and 54% ± 2 vs. 41% ± 3, respectively). In addition, the percentages of penetrated oocytes significantly decreased (P ≤ 0.05) following insemination when the OECM-conditioned medium was added to 0.01%, 0.05%, and 0.1% ethanol compared to the control (25% ± 4, 19% ± 2, 18% ± 3, and 45% ± 3, respectively). Sperm penetration rates significantly (P ≤ 0.01) decreased when the OECM-conditioned medium was heated to 100°C for 5 min (10% ± 1 vs. 40% ± 3). These results suggest that the active capacitating factor was sereted by the OECM and that this capacitating factor in the OECM-conditioned medium was inhibited by the presence of glucose. This factor was found to be heat-sensitive and its action was affected by ethanol. The OECM derived from the three phases of the estrous cycle as well as the presence of estradiol-17β influenced the capacity of the OECM to secrete this capacitating factor in Vitro. © 1995 wiley-Liss, Inc.  相似文献   

3.
The association between systemic lupus erythematosus (SLE) and malignancy has been controversial in the literature. We report a case of lung cancer in a 50-year-old woman with a 4-year history of SLE. She underwent surgery at a pathological stage of T2N2M0, but she eventually died of rapid recurrence of the cancer in the abdomen resulting in massive haemorrhage from the inferior vena cava (IVC). Immunological disorders related to SLE are thought to contribute to rapid progression of the malignancy.  相似文献   

4.
Small cell lung cancer (SCLC) is a type of high-grade neuroendocrine carcinoma. It initially responds to chemotherapy but rapidly becomes chemoresistant and it is highly proliferative. The prognosis in SCLC is poor. We have established a novel SCLC cell line, SCLC-J1, from a malignant pleural effusion in a patient with advanced SCLC. SCLC-J1 cells express ganglioside GD2, CD276, and Delta-like protein 3. RB1 is lost.These features of the new SCLC cell line may be useful in understanding the cellular and molecular biology of SCLC and in designing better treatment.  相似文献   

5.
EGF, known to sustain CNS neuronal progenitors, also promotes a neurotypic response in the thymic neural-crest-derived TC-1S cell line. We report here the use of TC-1S cells as a model to identify the genetic programs regulated during the neurotypic response induced by EGF and to isolate 23 EGF-responsive genes. Among them 5 represent novel cDNAs, while 18 are known genes, whose regulation by EGF is associated with the mitogenic or differentiating effects of the growth factor. The repression of smooth muscle alpha-actin and SM22alpha genes by EGF and their increase by TGFbeta suggest that the TC-1S line includes neural crest multipotent cells whose smooth muscle differentiation is repressed upon EGF treatment and stimulated by TGFbeta. Therefore, we identified a complex pattern of EGF-target genes and propose EGF as a novel signal able to recruit postmigratory neural-crest-derived cells along proliferation and cell lineage choice pathways.  相似文献   

6.
TGFβ can promote and/or suppress prostate tumor growth through multiple and opposing actions. Alterations of its expression, secretion, regulation or of the sensitivity of target cells can lead to a favorable environment for tumor development. To gain a better insight in TGFβ function during cancer progression, we have used different cultured human prostate cells: preneoplastic PNT2 cells, the androgen-dependent LNCaP and the androgen-independent PC3 and DU145 prostate cancer cell lines. We have studied by specific ELISA assays in conditioned media (CM), the secretion of TGFβ1 and TGFβ2 in basal conditions and after hormonal treatment (DHT or E2) and the expression of TGFβ1 mRNA by Northern blot. We have also compared the effect of fibroblast CM on TGFβ secretion by the different cell types. Compared to PNT2 cells, cancer cell lines secrete lower levels of active TGFβ which are not increased in the presence of fibroblast CM. LNCaP cells respond to androgen or estrogen treatment by a 10-fold increase of active TGFβ secretion while PC3 and DU145 are unresponsive. In conclusion, prostate cancer cell lines have lost part of their ability to secrete and activate TGFβ, and to regulate this secretion through stromal–epithelial interactions. Androgen-sensitive cancer cells may compensate this loss by hormonal regulation.  相似文献   

7.
Developmentally competent bovine blastocysts were produced by adding transforming growth factor beta (TGF beta) and basic fibroblast growth factor (bFGF) to serum-free cultures of in vitro produced, 2-cell bovine embryos. The effects of TGF beta were evaluated because this growth factor signals synthesis and secretion of the extracellular matrix component fibronectin and its receptor. Previous investigations have demonstrated that fibronectin promotes early bovine embryo development in vitro. The effects of TGF beta can be potentiated by bFGF; bFGF itself is an effector of protein synthesis and a potent mitogen. A positive interaction between the 2 growth factors resulted in 38.8% of fertilized oocytes maturing beyond the 16-cell stage; of these, 24.6% formed blastocysts. Transfer of early blastocysts produced using serum-free medium supplemented with growth factors resulted in pregnancy in 3 of 9 recipients. These results support the hypothesis that TGF beta and bFGF act synergistically to promote development of bovine embryos beyond the "8-cell block" observed in vitro.  相似文献   

8.
A routine, reproducible procedure was developed for the preparation and characterization of stromal cells from normal human breast tissue obtained by reduction mammaplasty. Isolates (n = 15) all exhibited enhanced rates of proliferation, even in the presence of 20% fetal calf serum, when exposed to epidermal growth factor or transforming growth factor a (both 10(-8) M). Cellular responsiveness to these growth factors was consistent with expression of specific surface receptors for epidermal growth factor (approximately 10(4)/cell). In cultures, stromal cells elaborated an extensive, cross-linked, insoluble extracellular matrix which remained firmly associated with the plastic surface of tissue culture ware upon lysis of cells. The insoluble matrix material was analyzed using enzymatic digestion procedures following incorporation of radiolabelled precursors into macromolecular material prior to lysis and preparation. The relative proportion of glycoconjugate (glycopeptides and proteoglycans) and collagenous material present in matrix material was approximately 45% and approximately 55%, respectively, and this was modulated by inclusion of epidermal growth factor into culture medium to approximately 60% and approximately 40%, respectively. Under similar culture conditions stromal cells synthesized twice as much hyaluronate as was produced by control cultures. By use of specific antibody preparations we identified at least four species of glycopeptide present in stromal matrices (namely, fibronectin, laminin, tenascin, and thrombospondin) as well as three types of collagen (types I, III, and IV). The rapid and reproducible procedure for the preparation of radiolabelled insoluble matrix material from normal human breast tissue allows for the study of cellular interaction involving extracellular matrix turnover and degradation.  相似文献   

9.
BACKGROUND: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is teratogenic in mice, producing cleft palate (CP). TCDD exposure disrupts expression of epidermal growth factor (EGF) receptor, EGF, and transforming growth factor-alpha (TGFalpha) in the palate and affects proliferation and differentiation of medial epithelial cells. EGF knockout embryos are less susceptible to the induction of CP by TCDD. This study used palate organ culture to examine the hypothesis that EGF enables a response to TCDD. METHODS: The midfacial tissues from wild-type (WT), EGF knockout, C57BL/6J, and TGFalpha knockout embryos were placed in organ culture on gestational day (GD) 12. Palatal explants were cultured for 4 days in serum-free Bigger's (BGJ) medium with 0.1% dimethyl sulfoxide (DMSO) or 1 x 10(-8) M TCDD with or without 2 ng of EGF/ml, 1 or 2 ng of TGFalpha/ml. Effects on palatal fusion were evaluated on day 4 of culture. EGF levels in explants and medium were determined using Luminex technology. RESULTS: In serum-free, control medium, palates from all of the strains fused. EGF knockout palates cultured with TCDD (no EGF) fused, but those cultured with TCDD + 2 ng of EGF/ml failed to fuse (p < 0.05 vs. control or TCDD without EGF). TGFalpha knockout palates failed to fuse when cultured with TCDD + 2 ng of TGFalpha/ml. EGF levels increased in tissue and accumulated in the medium after 24 hr of culture. CONCLUSIONS: This study demonstrated that providing EGF to the palates of EGF knockout mice restored the response to TCDD. These studies support the hypothesis that the mechanism for induction of CP by TCDD is mediated via the EGFR pathway.  相似文献   

10.
11.
During sepsis, hepatic apoptosis occurred, which is associated with inactivation of PKCalpha and elevation of tumor necrosis factor-alpha (TNFalpha), an apoptosis trigger. Heat shock, accompanied by the increase of heat-shock protein (Hsp72), has been shown to exhibit a protective role on cell survival. However, Hsp72 was unable to express during sepsis when the apoptosis was markedly increased. We hypothesized that hepatic apoptosis during sepsis may be due to the failure to induce expression of Hsp72, which is activated by PKC-phosphorylated HSF. This study was designed to examine the role of PKCalpha in Hsp72 expression and the anti-apoptotic effect of Hsp72 on hepatic epithelial cells by analyzing a TNFalpha-induced apoptosis system. The following results were observed: (1) Hsp72 was highly expressed at 8 h after heat-shock treatment in a clone 9 hepatic epithelial cell line; (2) the protein expression of PKCalpha in membrane-associated fraction was decreased by TNFalpha treatment; (3) the TNFalpha-induced cell death, especially apoptosis, was diminished by heat-shock pretreatment; (4) in the presence of PKCalpha antisense, which blocks the PKCalpha resynthesis, no protective effect of heat-shock pretreatment was observed, and the protein expression of Hsp72 was significantly suppressed. These results suggest that PKCalpha plays a critical role in the expression of Hsp72, which subsequently protects against TNFalpha-induced hepatic apoptosis.  相似文献   

12.
Cardiomyocytes are the fundamental cells of the heart and play an important role in engineering of tissue constructs for regenerative medicine and drug discovery. Therefore, the development of culture conditions that can be used to generate functional cardiomyocytes to form cardiac tissue may be of great interest. In this study, isolated neonatal rat cardiomyocytes were cultured with several culture conditions in vitro and characterized for cell proliferation, myofibril organization, and cardiac functionality by assessing cell morphology, immunocytochemical staining, and time-lapse confocal scanning microscopy. When cardiomyocytes were cultured in liver cell line derived conditioned medium without exogenous growth factors and cytokines, the cell proliferation increased, cell morphology was highly elongated, and subsequent myofibril organization was highly developed. These developed myofibril organization also showed high level of contractibility and synchronization, representing high functionality of cardiomyocytes. Interestingly, many of the known factors in hepatic conditioned medium, such as insulin-like growth factor II (IGFII), macrophage colony-stimulating factor (MCSF), leukemia inhibitory factor (LIF), did not show similar effects as the hepatic conditioned medium, suggesting the possibility of synergistic activity of the several soluble factors or the presence of unknown factors in hepatic conditioned medium. Finally, we demonstrated that our culture system could provide a potentially powerful tool for in vitro cardiac tissue organization and cardiac function study.  相似文献   

13.
Human prostatic carcinoma frequently metastasizes to bone tissue and activates bone metabolism, especially bone formation, at the site of metastasis. It has been reported that an extract of prostatic carcinoma and conditioned medium (CM) of a human prostatic carcinoma cell line, PC-3, established from a bone metastastic lesion, stimulate osteoblastic cell proliferation. However, there is little information about the effect of PC-3 CM on the differentiation of osteoblastic cells. In this study, we investigated the effect of PC-3 CM on the differentiation of two types of osteoblastic cells, primary fetal rat calvaria (RC) cells containing many undifferentiated osteoprogenitor cells, and ROS 17/2.8, a well-differentiated rat osteosarcoma cell line. PC-3 CM inhibited bone nodule formation and the activity of alkaline phosphatase (ALPase), an osteoblastic marker enzyme, on days 7, 14, and 21 (RC cells) or 3, 6, and 9 (ROS 17/2.8 cells) in a dose-dependent manner (5–30% CM). However, the CM did not affect cell proliferation or cell viability. PC-3 CM was found to markedly block the gene expression of ALPase and osteocalcin (OCN) mRNAs but had no effect on the mRNA expression of osteopontin (OPN), the latter two being noncollagenous proteins related to bone matrix mineralization. These findings suggest that PC-3 CM contains a factor that inhibits osteoblastic cell differentiation and that this factor may be involved in the process of bone metastasis from prostatic carcinoma. J. Cell. Biochem. 67:248–256, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

14.
15.
Hypertrophic cardiomyopathy (HCM) is the most common heritable cardiovascular disease. A recent study showed that male KLF10‐encoded TGFβ Inducible Early Gene‐1 knock‐out mice (TIEG?/?) develop HCM with 13‐fold up‐regulation of PTTG1‐encoded pituitary tumor‐transforming gene 1. We hypothesized TIEG1 could be a novel candidate gene in the pathogenesis of genotype negative HCM in humans, possibly through a loss of its repression on PTTG1 expression. A cohort of 923 unrelated patients from two independent HCM centers was analyzed for mutations in TIEG's four translated exons using DHPLC and direct DNA‐sequencing. Site directed mutagenesis was performed to clone novel variants. The effect of TIEG1 mutations on SMAD7 and PTTG1 promoters was studied using transient transfection and luciferase‐assays. Altered expression of PTTG1 in cardiac tissue was studied by immunohistochemistry (IHC) to determine levels of PTTG1 protein in hypertrophic diseases. Six novel TIEG1 missense mutations were discovered in six patients (two males/four females, mean age at diagnosis 56.2 ± 23 years, MLVWT 20.8 ± 4 mm). Compared to WT TIEG1, five TIEG1 mutants significantly increased PTTG1 promoter function similar to TIEG1?/?‐mice. By IHC, PTTG1‐protein expression was significantly increased in multiple models of hypertrophic cardiac disease, including TIEG1‐mutation positive HCM compared to normal hearts. This is the first article to associate mutations in TIEG1 to human disease with the discovery of six novel, HCM‐associated variants. Functional assays suggest a role for PTTG1 in the pathogenesis of TIEG1‐mediated HCM. Up‐regulation of PTTG1 seems to be a common pathway in hypertrophic heart disease, including TIEG1‐mediated HCM. J. Cell. Biochem. 113: 1896–1903, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   

16.
Leukemic blast growth factors (LBGFs) are necessary for in vitro growth of clonogenic cells from patients with acute myeloblastic leukemia. As the human bladder carcinoma cell line 5637 had previously been reported to secrete abundant LBGFs into the culture supernatant, the LBGFs in 5637-conditioned medium (5637-CM) were characterized. Measurement of LBGFs was done using an in vitro leukemic blast colony assay in methylcellulose culture. LBGFs in 5637-CM were fractionated by anion exchange chromatography, and two peaks of activity were recovered. Pool B (high-salt eluent) and/or purified granulocyte colony-stimulating factor (G-CSF) were added to the clonogenic leukemic blast cell assays. It was found that pool B was more active than G-CSF in the majority of cases examined and that the two types of activity were synergistic in some cases.  相似文献   

17.
Spreading of SNU16mAd gastric carcinoma cells was previously shown to be regulated via a signaling network from transforming growth factor beta1 (TGFbeta1) to integrins signaling, through a mediation of protein kinase C delta (PKCdelta). However, in the previous study, the roles of PKCdelta appeared complicated. In this study to clarify the roles of PKCdelta in the spreading of the gastric carcinoma cells, we questioned if PKC activation via phorbol 12-myristate 13-acetate (PMA) treatment could mimic the TGFbeta1 effects. An acute PMA treatment increased phosphorylations of focal adhesion (FA) kinase, paxillin, c-Src, and cofilin, just as TGFbeta1 did. Furthermore, cell spreading mediated by TGFbeta1- or acute PMA treatment correlated with activation of RhoA, which regulates actin reorganization and FA formation. However, stress fiber formation was prominent in TGFbeta1-treated cells, compared to cortical actin organization in PMA-treated cells. Altogether, these observations indicate that acute PMA treatment could mimic the TGFbeta1 mechanisms for cell spreading through subtly different effects on actin reorganization.  相似文献   

18.
A 300-fold adriamycin resistant variant (DLKP-A) of the human lung squamous cell carcinoma line DLKP was established by stepwise selection in increasing concentrations of adriamycin. Different levels of cross-resistance were observed towards VP-16, VM-26, colchicine, vincristine and, somewhat unexpectedly, cis-platin. Resistance was stable for at least 3 months in culture in the absence of drug. P-glycoprotein overexpression was detected by immunofluorescence and Western Blotting, and a direct causal role for P-glycoprotein overexpression in the resistant phenotype was established by transfection with an mdr1 specific antisense oligonucleotide. A modified cryopreservation procedure was necessary for the resistant variant line. The resistant population displays clonal heterogeneity with respect to resistance level. A higher frequency of double minute chromosomes was observed in DLKP-A when compared with the parental cell line.Abbreviations ADR adriamycin - COLH colchicine - C-PT cis-platin - MDR multidrug resistance - NSCLC non-small cell lung carcinoma - VCR vincristine - VP-16 etoposide - VM-26 tenoposide  相似文献   

19.
Neutrophils (PMN) are the major host defence cells protecting the body against invasion by microorganisms. Products of oxidative metabolism mediate PMN microbicidal and tumoricidal activity, but the mechanisms by which these pathways become activated are not well understood. The colony stimulating factors (CSF) are known to stimulate proliferation and differentiation of committed bone marrow stem cells. These regulators may probably play an important role in non specific resistance to infections. We studied the oxidative metabolism of neutrophils after stimulation with recombinant GM-CSF (r.GM-CSF) and the concentrated conditioned medium of the UBC-5637 cell line (UBC-CM) showing CSF activity. It could be demonstrated that the r.GM-CSF, as well as the UBC-CM, induce an activation of the neutrophil respiratory burst without any cofactors such as f-MLP, PMA, or zymosan. In addition, we observed an increase of the response to those stimulants in the presence of either r.GM-CSF or UBC-CM. These effects were not endotoxin-induced, since stimulation persisted after addition of Polymyxin B, which is known to inhibit the action of endotoxins.  相似文献   

20.
It has been reported that chemokine CX3CL1 can regulate various tumours by binding to its unique receptor CX3CR1. However, the effect of CX3CL1-CX3CR1 on the lung adenocarcinoma and lung squamous cell carcinoma is still unclear. Here, we showed that CX3CL1 can further invasion and migration of lung adenocarcinoma A549 and lung squamous cell carcinoma H520. In addition, Western blot and immunofluorescence test indicated CX3CL1 up-regulated the phosphorylation level of cortactin, which is a marker of cell pseudopodium. Meanwhile, the phosphorylation levels of c-Src and c-Abl, which are closely related to the regulation of cortactin phosphorylation, are elevated. Nevertheless, the src/abl inhibitor bosutinib and mutations of cortactin phosphorylation site could inhibit the promotion effect of CX3CL1 on invasion and migration of A549 and H520. Moreover, these results of MTT, Hoechst staining and Western blot suggested that CX3CL1 had no effect on the proliferation and apoptosis of A549 and H520 in vitro. The effects of CX3CL1 were also verified by the subcutaneous tumour formation in nude mice, which showed that it could promote proliferation and invasion of A549 in vivo. In summary, our results indicated that CX3CL1 furthered invasion and migration in lung cancer cells partly via activating cortactin, and CX3CL1 may be a potential molecule in regulating the migration and invasion of lung cancer.  相似文献   

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