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141.
Sevinc Yanar Murat Kasap Aylin Kanli Gurler Akpinar Mehmet Sarihan 《Journal of biochemical and molecular toxicology》2023,37(4):e23289
Small cell lung carcinoma (SCLC) is a highly aggressive cancer with low survival rate. Although initial response to chemotherapy in SCLC patients is well-rated, the treatments applied after the disease relapses are not successful. Drug resistance is accepted to be one of the main reasons for this failure. Therefore, there is an urgent need for new treatment strategies for SCLC. Meclofenamic acid, a nonsteroidal anti-inflammatory drug, has been shown to have anticancer effects on various types of cancers via different mechanisms. The aim of this study was to investigate the alterations that meclofenamic acid caused on a SCLC cell line, DMS114 using the tools of proteomics namely two-dimensional gel electrophoresis coupled to MALDI-TOF/TOF and nHPLC coupled to LC-MS/MS. Among the proteins identified by both methods, those showing significantly altered expression levels were evaluated using bioinformatics databases, PANTHER and STRING. The key altered metabolism upon meclofenamic acid treatment appeared to the cellular energy metabolism. Glycolysis was suppressed, whereas mitochondrial activity and oxidative phosphorylation were boosted. The cells underwent metabolic reprogramming to adapt into their new environment for survival. Metabolic reprogramming is known to cause drug resistance in several cancer types including SCLC. The identified differentially regulated proteins in here associated with energy metabolism hold value as the potential targets to overcome drug resistance in SCLC treatment. 相似文献
142.
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
143.
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
144.
145.
Ian G. Town Gary J. Phillips Edile Murdoch Stephen T. Holgate Frank J. Kelly 《Free radical research》1993,18(4):211-221
The time course and nature of the pulmonary inflammatory and antioxidant responses, both during and after hyperoxic-induced acute lung injury were studied in the preterm guinea pig. Three-day preterm (65 days gestation) guinea pigs were randomly exposed to either 21% O2 (control) or 95% O2 (hyperoxia) for 72 hours. All pups were then maintained in ambient conditions for up to a further 11 days, during which time lung damage was monitored. In animals exposed to hyperoxia, evidence of acute lung injury and inflammation was characterized by a marked increase in microvascular permeability and elevated numbers of neutrophils in bronchoalveolar lavage fluid. Protein concentration, elastase-like activity and elastase-inhibitory capacity in lavage fluid were at a maximum at the end of the 72 hours hyperoxic exposure. Four days later, all values had returned to control levels. In contrast, increased numbers of neutrophils, macrophages and lymphocytes were recovered in the lavage fluid during this early recovery period. Coinciding with the influx of inflammatory cells, there was a significant increase in glutathione peroxidase, manganese superoxide dismutase and catalase activities in immature lung. Lung copper/zinc superoxide dismutase activity remained unchanged during both experimental periods. The strong temporal relationship between the influx of inflammatory cells to the lung and the induction of pulmonary antioxidant enzyme defences suggests that a common mechanism underlies both responses. These findings have led us to regard inflammation in the hyperoxic-injured immature lung as a beneficial event and not, as previously suggested, as part of the injurious process. 相似文献
146.
Anatoly M. Malygin Alexander A. Redjko Olga N. Pogodina Nina A. Karaseva Yuri F. Koval' Tuomo Timonen 《Cancer immunology, immunotherapy : CII》1993,36(1):61-64
The prognostic value of peripheral blood non-MHC-restricted cytotoxicity against the myeloid leukaemic line K562 in lung cancer patients was studied. At the time of diagnosis and before operation, 57 patients with lung cancer were tested for cytotoxicity and subsequently followed for up to 4 years. In addition, 145 lung cancer patients, 30 patients with non-neoplastic lung diseases and 76 healthy donors were tested for cytotoxicity without the follow-up, in order to correlate the stage of lung cancer and the growth rate of tumours to the level of non-MHC-restricted cytotoxicity. On average, lung cancer patients had similar non-MHC-restricted cytotoxicity to the controls. However, patients with stage II–IV diseases showed an impaired activity, stages III and IV differing significantly from the controls. This result shows that the decline in natural killer (NK) activity is associated with tumour burden. Patients with slowly growing neoplasms had stronger cytotoxic activity than patients with fast or moderately progressing disease. In the follow-up study, the whole material of 57 patients showed only a slight correlation between cytotoxicity and survival: 42% of the patients with strong activity survived for more than 2.5 years, whereas 6% of the patients with weak activity did so. In stage I patients there was no correlation between cytotoxicity and survival, nor was there a correlation in patients with stages II–IV of the disease. Hence, in our group of patients the determination of cytotoxicity preoperatively yielded no prognostic information beyound that already available from staging. However, those stage II–IV patients that survived for 1 year or more after the diagnosis and cytotoxicity tests, showed a significant correlation between cytotoxicity and survival. 相似文献
147.
Toshiyuki Takahashi Hiroshi Ishikura Kazuhiro Iwai Chisa Takahashi Hiroyuki Kato Tatsuzo Tanabe Takashi Yoshiki 《Cancer immunology, immunotherapy : CII》1993,36(2):76-82
The permanent pancreas carcinoma cell line, PCI-24, was developed in order to analyse cytokine regulation on pancreas carcinoma and lymphokine-activated killer (LAK) cell interaction. PCI cells expressed ICAM-1 and HLA-ABC, but not HLA-DR antigens. PCI cells showed augmented ICAM-1 and HLA-ABC expression when incubated with interferon (IFN) and tumour necrosis factor . A similar but weak augmentary effect on the HLA-ABC and ICAM-1 surface expression was seen with interleukin-1 treatment. Natural attachment of LAK to PCI cells was augmented by recombinant IFN in close association with ICAM-1 up-regulation on PCI cells. In addition, natural attachment was significantly inhibited by anti-LFA-1 and anti-ICAM-1 antibody treatments. Cytotoxicity of the LAK cells against PCI cells was also significantly inhibited with the same treatment. Thus, the attachment of LAK cells to PCI cells through LFA-1/ICAM-1 molecules appeared to be essential for the cytotoxicity for PCI cells. Pretreatment of PCI cells, but not of LAK cells, with IFN or other cytokines resulted in a decrease of susceptibility for LAK cell cytotoxicity. The decreased susceptibility inversely correlated with HLA-ABC expression on the PCI cells. The collective evidence indicates that, although LAK cell attachment to pancreas carcinoma cells through the LFA-1/ICAM-1 molecule is augmented by IFN, IFN treatment of pancreas carcinoma cells reduces LAK cell cytotoxicity possibly through an increase in HLA-ABC or a regulation of molecules closely associated to HLA-ABC expression. 相似文献
148.
149.
Yoshio Oka Tetsuro Kobayashi Shoichi Fujita Nariaki Matsuura Shigeru Okamoto Hideki Asakawa Atsuo Murata Takesada Mori 《In vitro cellular & developmental biology. Animal》1993,29(7):537-542
Summary A human anaplastic thyroid cancer cell line K-119, derived from a 77-yr-old woman who had developed marked neutrophilia and
underwent surgery for anaplastic thyroid cancer, has been established. The spindlelike and polygonal cells in shape are stably
proliferating since the beginning of its culture 2 yr ago. The cells grow rapidly and the population doubling time is 26 h.
The chromosomes show many abnormalities and many marker chromosomes have been observed. Heterotransplantation of the cells
into nude mice has resulted in the formation of tumors that are histologically interpreted as anaplastic cancer. The most
noteworthy characteristics of the cell line are the many Ki-67-positive cells (86.3%) and that the cell line spontaneously
secretes granulocyte colony-stimulating factor (G-CSF) and releases increased amounts of G-CSF in response to the stimulation
of tumor necrosis factor, interleukin 1α, and interleukin 1β. The conditioned medium obtained from K-119 cells contains an
autocrine factor stimulating the proliferation of themselves. 相似文献
150.
Mats E. Johansson 《植被学杂志》1993,4(5):621-632
Abstract. Two marginal and two central populations of the pseudo-annual aquatic plant Ranunculus lingua were studied over four years. The main purpose was to quantify potentially influential abiotic and biotic factors and to derive predictions about life-history differences between the populations. Variation in abundance and height of R. lingua ramets at different depths were related to water-level fluctuations, to abundance of other helophyes (emergent macrophytes), and to the occurrence of invertebrate grazing and fungal pathogens. Clear differences between marginal and central populations were shown in the depth distribution of ramet numbers and ramet heights, as well as in the dynamic patterns, where marginal populations had a higher flux of ramets. These patterns and regression analyses indicated that abiotic factors have a greater influence in marginal populations, whereas biotic factors are more important in central populations. It is suggested that marginal habitats for R. lingua would favour life-histories with a high reproductive capacity, whereas a large size of ramet would be the most important life-history feature in central habitats. This was supported by the fact that ramets in marginal populations, in spite of their smaller size, produced higher number of rhizomes than ramets in central populations. Variation in regional abundance was finally related to differences in demographic processes and dispersal potential between the populations. 相似文献