• Title, Summary, Keyword: Antiproliferative effect

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Anticancer Effect of COX-2 Inhibitor DuP-697 Alone and in Combination with Tyrosine Kinase Inhibitor (E7080) on Colon Cancer Cell Lines

  • Altun, Ahmet;Turgut, Nergiz Hacer;Kaya, Tijen Temiz
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.7
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    • pp.3113-3121
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    • 2014
  • Colorectal cancer remains one of the most common types of cancer and a leading cause of cancer death worldwide. In this study, we aimed to investigate effects of DuP-697, an irreversible selective inhibitor of COX-2 on colorectal cancer cells alone and in combination with a promising new multi-targeted kinase inhibitor E7080. The HT29 colorectal cancer cell line was used. Real time cell analysis (xCELLigence system) was conducted to determine effects on colorectal cell proliferation, angiogenesis was assessed with a chorioallantoic membrane model and apoptosis was determined with annexin V staining. We found that DuP-697 alone exerted antiproliferative, antiangiogenic and apoptotic effects on HT29 colorectal cancer cells. For the antiproliferative effect the half maximum inhibition concentration ($IC_{50}$) was $4.28{\times}10^{-8}mol/L$. Antiangiogenic scores were 1.2, 0.8 and 0.5 for 100, 10 and 1 nmol/L DuP-697 concentrations, respectively. We detected apoptosis in 52% of HT29 colorectal cancer cells after administration of 100 nmol/L DuP-697. Also in combination with the thyrosine kinase inhibitor E7080 strong antiproliferative, antiangiogenic and apoptotic effects on HT29 colorectal cancer cells were observed. This study indicates that DuP-697 may be a promising agent in the treatment of colorectal cancer. Additionally the increased effects observed in the combination with thyrosine kinase inhibitor give the possibility to use lower doses of DuP-697 and E7080 which can avoid and/or minimize side effects.

Effects of Hypobaric Conditions on Apoptosis Signalling Pathways in HeLa Cells

  • Arican, Gul Ozcan;Khalilia, Walid;Serbes, Ugur;Akman, Gizem;Cetin, Idil;Arican, Ercan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.12
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    • pp.5043-5047
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    • 2014
  • Nowadays increasing effectiveness in cancer therapy and investigation of formation of new strategies that enhance antiproliferative activity against target organs has become a subject of interest. Although the molecular mechanisms of apoptosis can not be fully explained, it is known that cell suicide program existing in their memory genetically is activated by pathophysiological conditions and events such as oxidative stress. Low pressure (hypobaric) conditions that create hypoxia promote apoptosis by inhibiting cell cycling. In this study, determination of the effects of fractional hypobaric applications at different times on HeLa cells at cellular and molecular levels were targeted. Experiments were carried out under hypobaric conditions (35.2 kPa) in a specially designed hypobaric cabin including 2% $O_2$ and 98% N. Application of fractional hypobaric conditions was repeated two times for 3 hours with an interval of 24 hours. At the end of the implementation period cells were allowed to incubate for 24 hours for activation of repair mechanisms. Cell kinetic parameters such as growth rate (MTT) and apoptotic index were used in determination of the effect of hypobaric conditions on HeLa cells. Also in our study expression levels of the Bcl-2 gene family that have regulatory roles in apoptosis were determined by the RT-PCR technique to evaluate molecular mechanisms. The results showed that antiproliferative effect of hypobaric conditions on HeLa cells started three hours from the time of application and increased depending on the period of exposure. While there was a significant decrease in growth rate values, there was a significant increase in apoptotic index values (p<0.01). Also molecular studies showed that hypobaric conditions caused a significant increase in expression level of proapoptotic gene Bax and significant decrease in antiapoptotic Bfl-1. Consequently fractional application of hypobaric conditions on HeLa cell cultures increased both antiproliferative and apoptotic effects and these effects were triggered by the Bax gene.

PKB phosphorylates p27, impairs its nuclear import and opposes p27-mediated G1 arrest

  • Lee, Jin-Hwa;Liang, Ji-Yong;Slingerland, Joyce M.
    • Proceedings of the Korean Society of Life Science Conference
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    • pp.36-39
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    • 2002
  • PKB activation may contribute to resistance to antiproliferative signals and breast cancer progression in part by impairing nuclear import and action of p27. PKB transfection caused cytoplasmic p27 accumulation and cytokine resistance. The nuclear localization region of p27 contains a PKB/Akt consensus site at threonine 157 and p27 phosphorylation by PKB impaired its nuclear import in vitro. PKB/Akt phosphorylated wild type p27 but not p27T157A. PKB activation led to cytoplasmic mislocalization of p27WT but p27T157A remained nuclear. In PKB activated cells, p27WT failed to cause Gl arrest, while the antiproliferative effect of p27T157A was not impaired. Cytoplasmic p27 was seen in 41% (52/128) of primary human breast cancers in association with PKB activation. Thus, we show a novel mechanism whereby PKB impairs p27 function that is associated with an aggressive phenotype in human breast cancer.

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Comparative Study on the Cytotoxic Activities of Red Ginseng of Korea and China (한국 및 중국 홍삼의 암세포 증식억제 효과 비교연구(III))

  • 황우익;손정원
    • Journal of Ginseng Research
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    • v.17 no.3
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    • pp.196-202
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    • 1993
  • A study was performed to compare the anticancer effects of Korean and Chinese red ginseng roots. The whole crude extracts or chloroform, methanol and acetone fractions of the crude extracts were added in the culture medium of three cancer cell lines, a mouse leukemia cell line ($P_{388}$), a human colon carcinoma cell line (HT-29) and a human rectal carcinoma cell line (HRT-18), to screen the growth inhibition effects. The results are summarized as follows : 1. Crude extracts of both Korean and Chinese red ginseng roots inhibited the proliferation of all the three cancer cell lines tested in a dose dependent manner. However, the growth inhibition effects of Korean red ginseng extracts were significantly greater than that of Chinese red ginseng. 2. An acetone fraction showed the greatest antiproliferative effects among the 11'hole crude extracts, chloroform, methanol and acetone fractions of the crude extracts. 3. These results suggest that the active antiproliferative components of the crude extracts are present mostly in the acetone fraction.

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Memantine Induces NMDAR1-Mediated Autophagic Cell Death in Malignant Glioma Cells

  • Yoon, Wan-Soo;Yeom, Mi-Young;Kang, Eun-Sun;Chung, Yong-An;Chung, Dong-Sup;Jeun, Sin-Soo
    • Journal of Korean Neurosurgical Society
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    • v.60 no.2
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    • pp.130-137
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    • 2017
  • Objective : Autophagy is one of the key responses of cells to programmed cell death. Memantine, an approved anti-dementia drug, has an antiproliferative effect on cancer cells but the mechanism is poorly understood. The aim of the present study was to test the possibility of induction of autophagic cell death by memantine in glioma cell lines. Methods : Glioma cell lines (T-98 G and U-251 MG) were used for this study. Results : The antiproliferative effect of memantine was shown on T-98 G cells, which expressed N-methyl-D-aspartate 1 receptor (NMDAR1). Memantine increased the autophagic-related proteins as the conversion ratio of light chain protein 3-II (LC3-II)-/LC3-I and the expression of beclin-1. Memantine also increased formation of autophagic vacuoles observed under a transmission electron microscope. Transfection of small interfering RNA (siRNA) to knock down NMDAR1 in the glioma cells induced resistance to memantine and decreased the LC3-II/LC3-I ratio in T-98 G cells. Conclusion : Our study demonstrates that in glioma cells, memantine inhibits proliferation and induces autophagy mediated by NMDAR1.

Role of Pentacyclic Triterpenoids in Chemoprevention and Anticancer Treatment: An Overview on Targets and Underling Mechanisms

  • Ghante, Mahavir H.;Jamkhande, Prasad G.
    • Journal of Pharmacopuncture
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    • v.22 no.2
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    • pp.55-67
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    • 2019
  • The incidences of cancer are continuously increasing worldwide, affecting life of millions of people. Several factors associated with the internal and external environment are responsible for this deadly disease. The key internal determinants like abnormal hormonal regulation, genetic mutations and external determinants such as lifestyle and occupational factors enhances onset of cancer. From the ancient time, plants were remained as the most trusted source of medicine for the treatment of diverse disease conditions. Extensive studies have been performed for the discovery of effective anticancer agent from the plant and still it is going on. Pentacyclic triterpenoids are biologically active phytochemicals having a different range of activities such as anti-inflammatory, hepatoprotective, anti-hypertensive, antiulcerogenic and anti-tumor. These compounds generally contain ursane, oleanane, lupane and friedelane as a chief skeleton of pentacyclic triterpenoids which are generally present in higher plants. Isoprene unit, phytochemical, with good antitumor/anticancer activity is required for the biosynthesis of pentacyclic triterpenoids. Mechanisms such as cytotoxicity, DNA polymerase inhibition, regulation of apoptosis, change in signal transductions, interfere with angiogenesis and dedifferentiation, antiproliferative activity and metastasis inhibition are might be responsible for their anticancer effect. Present review spotlights diverse targets, mechanisms and pathways of pentacyclic triterpenoids responsible for anticancer effect.

Effect of Soy Isoflavones on the Expression of $TGF-{\beta}1$ and Its Receptors in Cultured Human Breast Cancer Cell Lines

  • Kim Young-Hwa;Jin Kyong-Suk;Lee Yong-Woo
    • Biomedical Science Letters
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    • v.11 no.2
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    • pp.175-183
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    • 2005
  • The two major isoflavones in soy, genistein and daidzein, are well known to prevent hormone-dependent cancers by their anti estrogenic activity. The exact molecular mechanisms for the protective action are, however, not provided yet. It has been reported that genistein and daidzein have a potential anticancer activity through their antiproliferative effect in many hormone-dependent cancer cell lines. Transforming growth $factor-\beta1(TGF-\beta1)$ has also been found to have cell growth inhibitory effect, especially in mammary epithelial cells. This knowledge led to a hypothetical mechanism that the soy isoflavones-induced growth inhibitory effect can be derived from the regulation of $TGF-\beta1$ and $TGF-\beta$ receptors. In order to test this hypothesis, the effects of the soy isoflavones at various concentrations and periods on the expression of $TGF-\beta1$and $TGF-\beta$ receptors were investigated by using Northern blot analysis in human breast carcinoma epithelial cell lines, an estrogen receptor positive cell line (MCF-7) and an estrogen receptor negative cell line (MDA-MB-231). As a result, only genistein has shown a profound dose-dependent effect on $TGF-\beta1$ expression in the $ER^+$ cell line within the range of doses tested, and the expression levels are correspondent to their inhibitory activities of cell growth. Moreover, daidzein showed down-regulated $TGF-\beta1$ expression at a low dose, the cell growth proliferation was promoted at the same condition. Therefore, antiproliferative activity of the soy isoflavones can be mediated by $TGF-\beta1$ expression, and the effects are mainly, if not all, occurred by ER dependent pathway. The expression of $TGF-\beta$ receptors was induced at a lower dose than the one for $TGF-{\beta}1$ induction regardless of the presence of ER, and the expression patterns are similar to those of the cell growth inhibition. These results indicated that the regulation of $TGF-\beta$ receptor expression as well, prior to $TGF-\beta1$ expression, may be involved in the antiproliferative activity of soy isoflavones. Little or no expression of $TGF-\beta$ receptors was found in the MCF-7 and MDA-MB-231 cells, suggesting refractory properties of the cells to growth inhibitory effect of the $TGF-\beta$. The soy isoflavones can seemingly restore the sensitivity of growth inhibitory responses to $TGF-\beta1$ by re-inducing $TGF-\beta$ receptors expression. In conclusions, our findings presented in this study show that the antitumorigenic activity of the soy isoflavones could be mediated by not only $TGF-\beta1$induction but $TGF-\beta$ receptor restoration. Thus, soy isoflavones could be good model molecules to develop new nonsteroidal antiestrogenic chemopreventive agents, associated with, regulation of $TGF-\beta$ and its receptors.

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