• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6135-6140
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• 2013

Background: Breast cancer is a common malignant tumor which affects health of women and multidrug resistance (MDR) is one of the main factors leading to failure of chemotherapy. This study was conducted to establish paclitaxel-resistant breast cancer cell line and nude mice models to explore underlying mechanisms of MDR. Methods: The breast cancer drug-sensitive cell line MCF-7 (MCF-7/S) was exposed in stepwise escalating paclitaxel (TAX) to induce a resistant cell line MCF-7/TAX. Cell sensitivity to drugs and growth curves were measured by MTT assay. Changes of cell morphology and ultrastructure were examined by optical and electron microscopy. The cell cycle distribution was determined by flow cytometry. Furthermore, expression of proteins related to breast cancer occurrence and MDR was tested by immunocytochemistry. In Vivo, nude mice were injected with MCF-7/S and MCF-7/TAX cells and weights and tumor sizes were observed after paclitaxel treatment. In addition, proteins involved breast cancer and MDR were detected by immunohistochemistry. Results: Compared to MCF-7/S, MCF-7/TAX cells had a higher resistance to paclitaxel, cross-resistance and prolonged doubling time. Moreover, MCF-7/TAX showed obvious alterations of ultrastructure. Estrogen receptor (ER) expression was low in drug resistant cells and tumors while expression of human epidermal growth factor receptor 2 (HER2) and Ki-67 was up-regulated. P-glycoprotein (P-gp), lung resistance-related protein (LRP) and glutathione-S-transferase-${\pi}$ (GST-${\pi}$) involved in the MDR phenotype of resistant cells and tumors were all overexpressed. Conclusion: The underlying MDR mechanism of breast cancer may involve increased expression of P-gp, LRP and GST-${\pi}$.

• Herbal Formula Science
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• v.30 no.3
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• pp.175-182
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• 2022

Objective : This study aims to investigate the active ingredients and potential mechanisms of the beneficial herb on human cancers such as the liver by employing network pharmacology. Methods : Ingredients and their target information was obtained from various databases such as TM-MC, TTD, and Drugbank. Related protein for liver cancer was retrieved from the Comparative Toxicogenomics Database and literature. A hypergeometric test and gene set enrichment analysis were conducted to evaluate associations between protein targets of red ginseng (Panax ginseng C. A. Meyer) and liver cancer-related proteins and identify related signaling pathways, respectively. Network proximity was employed to identify active ingredients of red ginseng on liver cancer. Results : A compound-target network of red ginseng was constructed, which consisted of 363 edges between 53 ingredients and 121 protein targets. MAPK signaling pathway, PI3K-Akt signaling pathway, p53 signaling pathway, TGF-beta signaling pathway, and cell cycle pathway was significantly associated with protein targets of red ginseng. Network proximity results indicated that Ginsenoside Rg1, Acetic Acid, Ginsenoside Rh2, 20(R)-Ginsenoside Rg3, Notoginsenoside R1, Ginsenoside Rk1, 2-Methylfuran, Hexanal, Ginsenoside Rd, Ginsenoside Rh1 could be active ingredients of red ginseng against liver cancer. Conclusion : This study suggests that network-based approaches could be useful to explore potential mechanisms and active ingredients of red ginseng for liver cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.13
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• pp.5437-5442
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• 2014

Esophageal squamous cell carcinoma (ESCC) is one of the most malignancies with a poor prognosis. The phospholipase $C{\varepsilon}$ gene (PLCE1) encodes a novel ras-related protein effector mediating the effects of R-Ras on the actin cytoskeleton and membrane protrusion. However, molecular mechanisms pertinent to ESCC are unclear. We therefore designed PLCE1-special small interfering RNA and transfected to esophageal squamous cell (EC) 9706 cells to investigat the effects of PLCE1 gene silencing on the cell cycle and apoptosis of ESCC and indicate its important role in the development of ESCC. Esophageal cancer tissue specimens and normal esophageal mucosa were obtained and assayed by immunohistochemical staining to confirm overexpression of PLCE1 in neoplasias. Fluorescence microscopy was used to examine transfection efficiency, while the result of PLCE1 silencing was examined by reverse transcription (RT-PCR). Flow cytometry and annexin V apoptosis assays were used to assess the cell cycle and apoptosis, respectively. Expression of cyclin D1 and caspase-3 was detected by Western-blotting. The level of PLCE1 protein in esophageal cancer tissue was significantly higher than that in normal tissue. After transfection, the expression of PLCE1 mRNA in EC 9706 was significantly reduced, compared with the control group. Furthermore, flow cytometry results suggested that the PLCE1 gene silencing arrested the cell cycle in the G0/G1 phase; apoptosis was significantly higher than in the negative control group and mock group. PLCE1 gene silencing by RNAi resulted in decreased expression of cyclin D1 and increased expression of caspase-3. Our study suggests that PLCE1 may be an oncogene and play an important role in esophageal carcinogenesis through regulating proteins which control cell cycling and apoptosis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.11
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• pp.6549-6556
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• 2013

Leukemia stem cells (LSCs) play important roles in leukemia initiation, progression and relapse, and thus represent a critical target for therapeutic intervention. Hence, it is extremely urgent to explore new therapeutic strategies directly targeting LSCs for acute myelogenous leukemia (AML) therapy. We show here that Angelica sinensis polysaccharide (ASP), a major active component in Dong quai (Chinese Angelica sinensis), effectively inhibited human AML $CD34^+CD38^-$ cell proliferation in vitro culture in a dose-dependent manner while sparing normal hematopoietic stem and progenitor cells at physiologically achievable concentrations. Furthermore, ASP exerted cytotoxic effects on AML K562 cells, especially LSC-enriched $CD34^+CD38^-$ cells. Colony formation assays further showed that ASP significantly suppressed the formation of colonies derived from AML $CD34^+CD38^-$ cells but not those from normal $CD34^+CD38^-$ cells. Examination of the underlying mechanisms revealed that ASP induced $CD34^+CD38^-$ cell senescence, which was strongly associated with a series of characteristic events, including up-regulation of p53, p16, p21, and Rb genes and changes of related cell cycle regulation proteins P16, P21, cyclin E and CDK4, telomere end attrition as well as repression of telomerase activity. On the basis of these findings, we propose that ASP represents a potentially important agent for leukemia stem cell-targeted therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.4983-4988
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• 2013

Objectives: To establish a taxol-resistant cell line of human ovarian carcinoma (A2780/Taxol) and investigate its biological features. Methods: The drug-resistant cell line (A2780/Taxol) was established by continuous stepwise selection with increasing concentrations of Taxol. Cell morphology was assessed by microscopy and growth curves were generated with in vitro and in vivo tumor xenograft models. With rhodamine123 (Rh123) assays, cell cycle distribution and the apoptotic rate were analyzed by flow cytometry (FCM). Drug resistance-related and signal associated proteins, including P-gp, MRPs, caveolin-1, PKC-${\alpha}$, Akt, ERK1/2, were detected by Western blotting. Results: A2780/Taxol cells were established with stable resistance to taxol. The drug resistance index (RI) was 430.7. Cross-resistance to other drugs was also shown, but there was no significant change to radioresistance. Compared with parental cells, A2780/Taxol cells were significantly heteromorphous, with a significant delay in population doubling time and reduced uptake of Rh123 (p<0.01). In vivo, tumor take by A2780 cells was 80%, and tumor volume increased gradually. In contrast, with A2780/Taxol cells in xenograft models there was no tumor development. FCM analysis revealed that A2780/Taxol cells had a higher percentage of G0/G1 and lower S phase, but no changes of G2 phase and the apoptosis rate. Expression of P-gp, MRP1, MRP2, BCRP, LRP, caveolin-1, PKC-${\alpha}$, Phospho-ERK1/2 and Phospho-JNK protein was significantly up-regulated, while Akt and p38 MARK protein expression was not changed in A2780/Taxol cells. Conclusion: The A2780/Taxol cell line is an ideal model to investigate the mechanism of muti-drug resistance related to overexpression of drug-resistance associated proteins and activation of the PKC-${\alpha}/ERK$ (JNK) signaling pathway.

• Annals of Surgical Treatment and Research
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• v.95 no.5
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• pp.240-248
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• 2018

Purpose: This study aimed to validate the synergistic effect of ABT-737 on docetaxel using MDA-MB-231, a triple negative breast cancer (TNBC) cell line overexpressing B-cell lymphoma-2 (Bcl-2). Methods: Western blot analysis was performed to assess expression levels of Bcl-2 family proteins and caspase-related molecules. Cell viability was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Cell cycle distribution was determined by flow cytometry analysis. Benzyloxycarbonyl-Val-Ala-Asp(OMe)-fluoromethylketone (z-VAD-fmk) was used for pretreatment to assess the role of caspases. Results: Cell viability of MDA-MB-231 after combination treatment with ABT-737 and docetaxel was significantly lower than that after docetaxel or ABT-737 monotherapy based on MTT assay (both P < 0.001), with a combination index of 0.41. The proportion of sub-G1 population after combination treatment was significantly higher than that after docetaxel or ABT-737 monotherapy (P = 0.001, P = 0.003, respectively). Pretreatment with z-VAD-fmk completely restored cell viability of MDA-MB-231 from apoptotic cell death induced by combination therapy (P = 0.001). Although pro-caspase-8 or Bid did not show significant change in expression level, pro-casepase-9 showed significantly decreased expression after combination treatment. Cleaved caspase-3 showed increased expression while poly (ADP-ribose) polymerase cleavage was induced after combination treatment. However, hypoxia-inducible factor 1-alpha and aldehyde dehydrogenase 1 totally lost their expression after combination treatment. Conclusion: Combination of ABT-737 with docetaxel elicits synergistic therapeutic effect on MDA-MB-231, a TNBC cell line overexpressing Bcl-2, mainly by activating the intrinsic pathway of apoptosis. Therefore, adjunct of ABT-737 to docetaxel might be a new therapeutic option to overcome docetaxel resistance of TNBCs overexpressing Bcl-2.

• Journal of Physiology & Pathology in Korean Medicine
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• v.20 no.5
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• pp.1303-1310
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• 2006

In oriental medicine, Samul-tang (SMT) has been used for the treatment of cardiovascular diseases and neuronal disorders. Here, possible effects of SMT on axonal regeneration after the spinal cord injury were examined. SMT treatment induced increases in regeneration-related proteins GAP-43, cell division cycle 2 (Cdc2) and phospho-Erk1/2 in the peripheral sciatic nerves after crush injury. Increased levels of Cdc2 and phospho-Erk1/2 were observe mostly in the gray matter area and some in the dorsomedial white matter. These increases correlated with increased cell numbers in affected areas. Moreover, axons of corticospinal tract (CST) showed increased sprouting in the injured spinal cord when administrated with SMT compared with saline-treated control. Thus, the present data indicate that SMT may be useful for identifying active components and for therapeutic application toward the treatment of spinal cord disorders after injury.

• Proceedings of the Ginseng society Conference
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• 2006.05a
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• pp.3-12
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• 2006

1 The present work was performed to investigate the effects of ginsenoside Rh2 on proliferation, cell cycle-regulation and differentiation of human leukemia HL-60 cells as well as the underlying mechanisms for these effects. 2 Ginsenoside Rh2 potently inhibited the proliferation of HL-60 cells in both a dose- and time-dependent manner with an $IC_{50}$, $20{\mu}M$. 3 DNA flow-cytometry indicated that ginsenoside Rh2 markedly induced a $G_1$ phase arrest of HL-60 cells. 4 Among the $G_1$ phase cell cycle-related proteins, the levels of cyclin-dependent kinase(CDK)4, 6 and cyclin D1, cyclin D2, cyclin D3 were reduced by ginsenoside Rh2, whereas the steadystate levels of CDK2 and cyclin E were unaffected. 5 The protein levels of a CDK inhibitor p16, $p21^{CIP1/WAF1}$ and $p27^{KIP1}$ were markedly increased by ginsenoside Rh2. 6 Ginsenoside Rh2 markedly enhanced the binding of $p21^{CIP1/WAF1}$ and $p27^{KIP1}$ with CDK2 and CDK6, resulting in the reduced activity of both kinases and the hypophosphorylation of Rb protein. 7 We furthermore suggest that ginsenoside Rh2 is a potent inducer of the differentiation of HL-60 cells, based on observations such as a reduction of the nitroblue tetrazolium level, an increase in the esterase activities and phagocytic activity, morphology changes, and the expression of CD11b, CD14, CD64 and CD66b surface antigens. 8 In conclusion, the onset of ginsenoside Rh2-induced the $G_0/G_1$ arrest of HL-60 cells prior to the differentiation is linked to a sharp up-regulation of the $p21^{CIP1/WAF1}$ level and a decrease in the CDK2, CDK4 and CDK6 activities. This is the first report demonstrating that ginsenoside Rh2 potently inhibits the proliferation of human promyelocytic HL-60 cells via the $G_1$ phase cell cycle arrest and differentiation induction.

• Journal of Veterinary Science
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• v.23 no.5
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• pp.74.1-74.16
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• 2022

Background: Previous studies have presented evidence to support the significant association between red meat intake and colon cancer, suggesting that heme iron plays a key role in colon carcinogenesis. Epigallocatechin-3-gallate (EGCG), the major constituent of green tea, exhibits anti-oxidative and anti-cancer effects. However, the effect of EGCG on red meat-associated colon carcinogenesis is not well understood. Objectives: We aimed to investigate the regulatory effects of hemin and EGCG on colon carcinogenesis and the underlying mechanism of action. Methods: Hemin and EGCG were treated in Caco2 cells to perform the water-soluble tetrazolium salt-1 assay, lactate dehydrogenase release assay, reactive oxygen species (ROS) detection assay, real-time quantitative polymerase chain reaction and western blot. We investigated the regulatory effects of hemin and EGCG on an azoxymethane (AOM) and dextran sodium sulfate (DSS)-induced colon carcinogenesis mouse model. Results: In Caco2 cells, hemin increased cell proliferation and the expression of cell cycle regulatory proteins, and ROS levels. EGCG suppressed hemin-induced cell proliferation and cell cycle regulatory protein expression as well as mitochondrial ROS accumulation. Hemin increased nuclear factor erythroid-2-related factor 2 (Nrf2) expression, but decreased Keap1 expression. EGCG enhanced hemin-induced Nrf2 and antioxidant gene expression. Nrf2 inhibitor reversed EGCG reduced cell proliferation and cell cycle regulatory protein expression. In AOM/DSS mice, hemin treatment induced hyperplastic changes in colon tissues, inhibited by EGCG supplementation. EGCG reduced the hemin-induced numbers of total aberrant crypts and malondialdehyde concentration in the AOM/DSS model. Conclusions: We demonstrated that EGCG reduced hemin-induced proliferation and colon carcinogenesis through Nrf2-inhibited mitochondrial ROS accumulation.

• Tuberculosis and Respiratory Diseases
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• v.53 no.3
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• pp.253-264
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• 2002

Background : It has been reported that the expression of protein which influences on the cell cycle is significantly involved in the development, progress, treatment response, and survival of cancer, and also that the degree of expression of p27 and CDK4 is related to the prognosis. Recent research has revealed that uteroglobin, tumor suppressor gene, is related to cell cycle. This study is focused on the relations between expression of proteins related to cell cycle and clinical index of and survival of NSCLC. Methods : We examined immunohistochemically specimens of 110 surgically resected NSCLCs for expression of p27, CDK, Uteroglobin. Tissue array slide were obtained from 110 surgically resected NSCLCs. Immunohistochemical staining was performed by immuno-peroxidase technique using avidin-biotinylated horseradish peroxidase complex. Results : In 110 patients with resected NSCLCs, the ratio of male to female was 87:13, the median age was $56.43{\pm}9.41$ yrs. The positive staining of p27 was detected in 75% of the cases. A non-statistically significant trend toward increased p27 expression was observed in smoker and squamous cell cancer. The positive staining of CDK4 was detected in 89%, which was the highest expression of protein among 3 types. The survival ratio of CDK4 negative staining group was higher than that of positive staining group, which was significant diffrernce(P<0.05). There was no association between p27 or uteroglobin expression and survival. Conclusion : The expression degree of CDK4 is related to the prognosis. This findings suggests that the measurement of CDK4 may be useful in identifying patient at high risk for disease recurrence and survival.