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91.
S. Wright-Perkins M. R. Daniel C. Walker 《In vitro cellular & developmental biology. Animal》1994,30(7):450-459
Summary This study investigates the characteristics of two human cell lines—1PT and 1PT VARIANT A—both derived from the same histologically
undifferentiated, neuroendocrine positive, non-small cell lung carcinoma (NSCLC) and capable of growth in unsupplemented serum-free
minimum essential medium. In stationary culture, the cells of both lines grew both attached to a plastic substratum and in
suspension; the 1PT VARIANT A line formed three-dimensional clusters of loosely adherent cells. The cell lines differed in
their DNA content, the 1PT having 1.44 times and the 1PT VARIANT A having 2.39 times the normal human diploid DNA content.
Chromosome counts supported this observation, the ploidy of the 1PT and VARIANT A lines being 1.11 and 1.64, respectively.
On transmission electron microscopy the cells of both lines had dense core granules and immature desmosomes, whereas only
the 1PT VARIANT A line had mucin granules. Both lines formed, in nude mice, tumors that, like the original tumor from which
they were derived, were histologically undifferentiated and showed local invasion. The original tumor and both lines had demonstrable
neuroendocrine markers. Cytokeratins were apparent in the tumor but not the cell lines, and neurofilaments were present in
the cell lines only. Staining for epithelial membrane antigen, neural cell adhesion molecule, and desmoplakin differentiated
between the two lines. These lines provide a useful model for the investigation of the biology of the neuroendocrine positive
subgroup of NSCLC, which is clinically important because of the possible responsiveness of these tumors to chemotherapy. 相似文献
92.
William R. Gower Jr. Robert M. Risch Constantine V. Godellas Peter J. Fabri 《In vitro cellular & developmental biology. Animal》1994,30(3):151-161
Summary A new human pancreatic cancer (HPAC) cell line was established from a nude mouse xenograft (CAP) of a primary human pancreatic
ductal adenocarcinoma. In culture, HPAC cells form monolayers of morphologically heterogenous, polar epithelial cells, which
synthesize carcinoembryonic antigen, CA 19-9, CA-125, cytokeratins, antigens for DU-PAN-2, HMFG1, and AUA1, but do not express
chromogranin A or vimentin indicative of their pancreatic ductal epithelial cell character. In the presence of serum, HPAC
cell DNA synthesis was stimulated by insulin, insulin growth factor-I, epidermal growth factor, and TGF-α but inhibited
by physiologic concentrations of hydrocortisone and dexamethasone. Dose-dependent inhibition of DNA synthesis was limited
to steroids with glucocorticoid activity. The inhibitory effect of dexamethasone was abolished by the glucocorticoid antagonist
RU 38486. Binding of [3H]dexamethasone to cytosolic proteins was specific and saturable at 4° C. Scatchard analysis of binding data demonstrated
a single class of high-affinity binding sites (Kd=3.8±0.9 nM; Bmax=523±128 fmol/mg protein). Western blot analysis revealed a major protein band that migrated at a Mr of 96 kDa. Northern blot analysis identified an mRNA of approximately 7 kilobases which hybridized with a specific glucocorticoid
receptor complementary DNA probe (OB7). These findings support a role for glucocorticoids in the regulation of human malignant
pancreatic cell function. 相似文献
93.
Wagner U. Reinsberg J. Schmidt S. Mallmann P. Schmolling J. Schultes B. Richter H. Biersack H. J. Krebs D. 《Cell biochemistry and biophysics》1994,24(1-3):237-242
Antibodies can be processed by the B- and T-cell systems and may lead to a selective activation of the immune system. The
network structure of the immune system implicates the possibility of a selective immunization by the activation of idiotypic
cascades.
In a retrospective analysis, patients with advanced ovarian carcinoma, who had received MAb, against the cancer-associated
antigen CA125 for diagnostic purposes, were analyzed for the production of anti-idiotypic antibodies, survival rate, and immunological
effects. Furthermore, we started a prospective and randomized study for ovarian cancer patients, using a different antigen,
TAG72, for the induction of idiotypic cascades.
Our first results on 58 patients with advanced ovarian carcinomas showed that the induction of anti-idiotypic-antibodies against
OC125 mimicking the TAA Class III CA125 leads to a prolongation of the survival rate, and, in extended stages, to an induction
of antitumoral immunity, and that the induction of idiotypic cascades is also possible for different antigens like TAG72.
Summarizing the activation of idio-typic network cascades seems to be a very effective way of intervention in the immune system
of patients with advanced stages of ovarian carcinoma. A prospective study of the adjuvant approach seems to be necessary. 相似文献
94.
G. K. Haines G. D. Ghadge S. Becker M. Kies H. Pelzer B. Thimmappaya J. A. Radosevich 《Virchows Archiv. B, Cell pathology including molecular pathology》1993,63(1):289-295
p68 is an inducible protein kinase which is believed to be an important factor in the regulation of both viral and cellular
protein synthesis. We have produced a monoclonal antibody (TJ4C4) which specifically detects p68, and which can be used to
detect this antigen in formalin-fixed, paraffin-embedded tissues. Because p68 plays an important role in cellular protein
synthesis, we hypothesized that it may correlate with normal and neoplastic cellular differentiation. One hundred and seventy-seven
head and neck squamous cell carcinoma specimens, representing 82 patients, were studied. The relative amount, frequency, and
distribution of p68 expression were determined by microscopic evaluation of ABC immunoperoxidase-stained specimens. A spectrum
of immunoreactivity was detected in 156 of 177 tumors, as well as within the normal squamous epithelium. Normal, actively
proliferating cells, such as the basal layer of squamous epithelium, expressed comparatively little p68. Increased p68 expression
was noted to parallel the morphologic features of cellular differentiation. In neoplastic tissue, p68 expression also increased
with the degree of cellular differentiation. These data demonstrate that the expression of p68 parallels the degree of cellular
differentiation in squamous cell carcinoma of the head and neck region, as well as within normal squamous mucosa. Therefore,
p68 may provide an objective biologic measure of cellular differentiation which does not depend on morphologic features. 相似文献
95.
采用SDS聚丙烯酰胺凝胶电泳银染色的方法,对58例肺癌患者和32例肺结核患者的血清蛋白进行比较分析,发现有五种特异蛋白,分别存在于A区、C区、F区和G区。肺癌组和肺结核组比较,存在极显著性差异(P<0.01),提示有早期诊断肺癌的价值,有可能成为临床诊断肺癌的一个重要参考指标。 相似文献
96.
本文对11例肺癌患者胸水13种游离氨基酸作了分析,并与28例正常人血浆游离氨基酸水平作了对照,结果表明:肺癌患者胸水的必需及非必需氨基酸普遍高于正常人血浆游离氨基酸,但其胸水谷氨酰胺水平则明显低于正常人血浆水平。 相似文献
97.
Seyede Saba Hosseini Seyed Omar Ebrahimi Maryam Haji Ghasem Kashani Somayeh Reiisi 《Cell biology international》2023,47(1):98-109
Naturally-derived drugs have drawn much attention in recent decades. Efficiency, lower toxicity, and economic reasons are some of their advantages that justify this broad range of administration for different diseases, including cancer. If we can find a specific combination that boosts the effects of their single therapy, leading to synergism effect, increased efficiency, and decreased toxicity, they can act even better. Quercetin and fisetin, two well-known flavonoids, have been used to fight against various cancers. In this study, we investigated their possible synergism quercetin and fisetin on MCF7, MDA-MB-231, BT549, T47D, and 4T1 breast cancer cell lines. Then the optimum combined dose was used to study their impacts on wound healing abilities and clonogenic properties. The real-time qPCR was used to study the expression of their validated downstream effectors in predicted pathways. A significant synergism effect (p < .01, combination index: <1) was observed for all cell lines. Combination therapy was significantly more effective in colony formation (p < .0001) and wound healing assays (p < .001) compared to single therapies. The expression level of potential effectors was also showed a greater change. In vivo study confirmed the in vitro results and showed how significantly (p < .001) their synergism promotes their singular function in inhibiting cancer progression. The breast cancer mouse models receiving combined therapy lived longer with higher average body weight and smaller tumor sizes. These results exhibit that quercetin and fisetin inhibit cancer cell proliferation, migration and colony formation synergistically, and matrix metalloproteinase signaling and apoptotic pathways are relatively responsible for inhibitory activities. 相似文献
98.
Eda Dagsuyu Pınar Koroglu Ilknur B. Gul Omur K. Bulan Refiye Yanardag 《Journal of biochemical and molecular toxicology》2023,37(10):e23440
The body can host the spread of prostate cancer cells. Metastases from prostate cancer are more frequently seen in the brain, liver, lungs, and lymph nodes. A well-known antidiabetic drug, metformin, is also known to have antitumor effects. Our study focuses on the evaluation of potential metformin protective effects on brain and cerebellum damage in streptozotocin (STZ)-induced diabetic and Dunning prostate cancer models. In this investigation, six groups of male Copenhagen rats were created: control, diabetic (D), cancer (C), diabetic + cancer (DC), cancer + metformin, and diabetic + cancer + metformin. The brain and cerebellum tissues of the rats were taken after sacrifice. Oxidative stress markers including reduced glutathione level, lipid peroxidation, glutathione reductase, glutathione peroxidase, glutathione-S-transferase, catalase, superoxide dismutase activities, reactive oxygen species, total oxidant and total antioxidant status, lactate dehydrogenase, xanthine oxidase, acetylcholinesterase activities, protein carbonyl contents, nitric oxide and OH-proline levels, sodium potassium ATPase, carbonic anhydrase, and glucose-6-phosphate dehydrogenase activities; glycoprotein levels including hexose, hexosamine, fucose, and sialic acid levels; and histone deacetylase activity as a cancer marker were determined. Oxidative stress markers were impaired and glycoprotein levels and histone deacetylase activity were increased in the D, C, and DC groups. Metformin therapy reversed these effects. Metformin was found to protect the brain and cerebellum of STZ-induced diabetic rats with Dunning prostate cancer from harm caused by MAT-Lylu metastatic cells. 相似文献
99.
Wei Dai Yong gang Dai Dong feng Ren Da wei Zhu 《Journal of biochemical and molecular toxicology》2023,37(5):e23313
This study investigated that dieckol (DKL), a natural drug, inhibits colon cancer cell proliferation and migration by inhibiting phosphoinositide-3-kinase (PI3K), protein kinase B (AKT), and mammalian target of rapamycin (mTOR) phosphorylation in HCT-116 cells. The cells were treated with DKL in various concentrations (32 and 50 μM) for 24 h and then analyzed for various experiments. MTT (tetrazolium bromide) and crystal violet assay investigated DKL-mediated cytotoxicity. Dichlorodihydrofluorescein diacetate staining was used to assess the reactive oxygen species (ROS) measurement, and apoptotic changes were studied by dual acridine orange and ethidium bromide staining. Protein expression of cell survival, cell cycle, proliferation, and apoptosis protein was evaluated by western blot analysis. Results indicated that DKL produces significant cytotoxicity in HCT-116, and the half-maximal inhibitory concentration was found to be 32 μM for 24-h incubation. Moreover, effective production of ROS and enhanced apoptotic signs were observed upon DKL treatment in HCT-116. DKL induces the expression of phosphorylated PI3K, AKT, and mToR-associated enhanced expression of cyclin-D1, proliferating cell nuclear antigen, cyclin-dependent kinase (CDK)-4, CDK-6, and Bcl-2 in HCT-116. In addition, proapoptotic proteins such as Bax, caspase-9, and caspase-3 were significantly enhanced by DKL treatment in HCT-116. Hence, DKL has been considered a chemotherapeutic drug by impeding the expression of PI3K-, AKT-, and mTOR-mediated inhibition of proliferation and cell cycle-regulating proteins. 相似文献
100.
Yasuiki Umezu Lazel B Augustus Dai Seito Kazuhiro Hayakawa Merric I Ross Omar Eton David A Swanson Kyogo Itoh 《Cancer immunology, immunotherapy : CII》1993,37(6):392-399
The roles of ultraviolet-B (UV) radiation in the immunogenicity of human cancer cells have not been fully studied. We have investigated the effects of UV radiation on metastatic melanoma and renal cell carcinoma cells with regard to MHC antigen expression and the ability to induce cytotoxic T lymphocyte (CTL) activity in peripheral blood mononuclear cells (PBMC) or tumor-infiltrating lymphocytes (TIL) against untreated autologous tumor cells. UV radiation respectively decreased or increased MHC class I expression of freshly isolated tumor cells or cultured tumor cells, and also decreased MHC class I expression of starved cultured tumor cells. It increased the ability of both freshly isolated and cultured tumor cells to induce CTL activity from PBMC against untreated autologous tumor cells. UV-irradiated subclones that were more susceptible to CTL lysis were more potent for CTL induction from TIL than either an untreated parental clone or a UV-irradiated subclone that was resistant to CTL lysis. In summary, UV radiation increased the ability of tumor cells to induce CTL activity without a corresponding effect on MHC antigen expression.This work was supported in part by a grant CA47891 from the National Cancer Institute, USA, a grant-in-aid of the comprehensive 10-years strategy for cancer control from ministry of a Health and Welfare, Japan, and the Ishibashi Research Fund, Japan 相似文献