• IMMUNE NETWORK
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• v.21 no.5
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• pp.34.1-34.16
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• 2021

Sjögren's syndrome (SS) is an autoimmune disease characterized by dryness of the mouth and eyes. The glandular dysfunction in SS involves not only T cell-mediated destruction of the glands but also autoantibodies against the type 3 muscarinic acetylcholine receptor or aquaporin 5 (AQP5) that interfere with the secretion process. Studies on the breakage of tolerance and induction of autoantibodies to these autoantigens could benefit SS patients. To break tolerance, we utilized a PmE-L peptide derived from the AQP5-homologous aquaporin of Prevotella melaninogenica (PmAqp) that contained both a B cell "E" epitope and a T cell epitope. Repeated subcutaneous immunization of C57BL/6 mice with the PmE-L peptide efficiently induced the production of Abs against the "E" epitope of mouse/human AQP5 (AQP5E), and we aimed to characterize the antigen specificity, the sequences of AQP5E-specific B cell receptors, and salivary gland phenotypes of these mice. Sera containing anti-AQP5E IgG not only stained mouse Aqp5 expressed in the submandibular glands but also detected PmApq and PmE-L by immunoblotting, suggesting molecular mimicry. Characterization of the AQP5E-specific autoantibodies selected from the screening of phage display Ab libraries and mapping of the B cell receptor repertoires revealed that the AQP5E-specific B cells acquired the ability to bind to the Ag through cumulative somatic hypermutation. Importantly, animals with anti-AQP5E Abs had decreased salivary flow rates without immune cell infiltration into the salivary glands. This model will be useful for investigating the role of anti-AQP5 autoantibodies in glandular dysfunction in SS and testing new therapeutics targeting autoantibody production.

• Journal of Acupuncture Research
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• v.21 no.2
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• pp.41-55
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• 2004

Objective : To investigate the possible molecular mechanism (s) of melittin as a candidate of anti-cancer drug, we examined the effects of the compound on the growth of human lung carcinoma cell line A549. Methods : Growth inhibitory study, flow cytometry analysis, SDS-polyacrylamide gel electrophoresis and Western blot analysis, RT-PCR and in vitro caspases activity assay were performed. Results : Melittin treatment declined the cell viability of A549 cells in a concentration-dependent manner, which was associated with induction of apoptotic cell death. Melittin treatment down-regulated the levels of Bcl-XS/L mRNA and protein expression of A549 cells, an anti-apoptotic gene, however, the those of Bax, a pro-apoptotic gene, were up-regulated. Melittin induced the proteolytic cleavage and activation of caspase-3 and caspase-9 protease in a dose-dependent manner without alteration of inhibitor of apoptosis proteins family and Akt expression. Western blot analysis and RT-PCR data revealed that the levels of tumor suppressor p53 and cyclin-dependent kinase inhibitor p21 were also remained unchanged. Conclusions : Taken together, these findings suggest that melittin-induced inhibition of human lung cancer cell growth is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products, and melittin may have therapeutic potential in human lung cancer.

• Journal of Pharmacopuncture
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• v.16 no.3
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• pp.11-22
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• 2013

Objectives: The present investigation aimed at examining if post-cancer treatment with a potentized homeopathic drug, Condurango 30C, which is generally used to treat oesophageal cancer, could also show an ameliorating effect through apoptosis induction on lung cancer induced by benzo[a]pyrene (BaP) in white rats (Rattus norvegicus). Methods: Lung cancer was induced after four months by chronic feeding of BaP to rats through gavage at a dose of 50 mg/kg body weight for one month. After four months, the lung-cancer-bearing rats were treated with Condurango 30C for the next one ($5^{th}$), two ($5^{th}-6^{th}$) and three ($5^{th}-7^{th}$) months, respectively, and were sacrificed at the corresponding time-points. The ameliorating effect, if any, after Condurango 30C treatment for the various periods was evaluated by using protocols such as histology, scanning electron microscopy (SEM), annexinV-FITC/PI assay, flow cytometry of the apoptosis marker, DNA fragmentation, reverse transcriptase-polymerase chain reaction (RT-PCR), immunohistochemistry, and western blot analyses of lung tissue samples. Results: Striking recovery of lung tissue to a near normal status was noticed after post-cancerous drug treatment, as evidenced by SEM and histology, especially after one and two months of drug treatment. Data from the annexinV-FITC/PI and DNA fragmentation assays revealed that Condurango 30C could induce apoptosis in cancer cells after post-cancer treatment. A critical analysis of signalling cascade, evidenced through a RT-PCR study, demonstrated up-regulation and down-regulation of different pro- and anti-apoptotic genes, respectively, related to a caspase-3-mediated apoptotic pathway, which was especially discernible after one-month and two-month drug treatments. Correspondingly, Western blot and immunohistochemistry studies confirmed the ameliorative potential of Condurango 30C by its ability to down-regulate the elevated epidermal growth factor receptor (EGFR) expression, a hallmark of lung cancer. Conclusion: The overall result validated a positive effect of Condurango 30C in ameliorating lung cancer through caspase-3-mediated apoptosis induction and EGFR down-regulation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.6
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• pp.714-720
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• 2008

Cordyceps militaris is a medicinal fungus which has been used for patient suffering from cancer in Oriental medicine. It was previously reported that C. militaris extracts are capable of inhibiting tumor growth and inducing apoptosis; however, the anti-poliferative effects of human cancer cells have been poorly understood. In this study, to elucidate the anti-cancer mechanisms of human cancer cells by treatment with aqueous extract of C. militaris (AECM), we investigated the anti-proliferative effects of AECM in human hepatocarcinoma Hep3B cells. AECM treatment inhibited the growth of Hep3B cells and induced the apoptotic cell death in a concentration-dependent manner such as formation of apoptotic bodies and increased populations of apoptotic-sub G1 phase. The induction of apoptosis by AECM was connected with a proteolytic activation of caspase-3 and caspase-8. and concomitant degradation of poly (ADP-ribose) polymerase (PARP) and ${\beta}$-catenin proteins. Furthermore, caspase-3 inhibitor, z-DEVD-fmk, significantly inhibited AECM-induced apoptosis demonstrating the important role of caspase-3 in the bserved cytotoxic effect. Taken together, these findings suggest that AECM-induced inhibition of human hepatocarcinoma cell proliferation is associated with the induction of apoptotic cell death via activation of caspase-3 and C. militaris may have therapeutic potential in human cancer.

• Journal of Ginseng Research
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• v.41 no.3
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• pp.247-256
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• 2017

Background: KG-135, a standardized formulation enriched with Rk1, Rg3, and Rg5 ginsenosides, has been shown to inhibit various types of cancer cells; however, the underlying mechanisms are not fully understood. In this study, we explored its effects in A549 human lung cancer cells to investigate the induction of Forkhead Class box O3a (FOXO3a) and autophagy. Methods: Cell viability was determined by sulforhodamine B staining. Apoptosis and cell cycle distribution were analyzed using flow cytometry. The changes of protein levels were determined using Western blot analysis. Autophagy induction was monitored by the formation of acidic vesicular organelles stained with acridine orange. Results: KG-135 effectively arrested the cells in G1 phase with limited apoptosis. Accordingly, a decrease of cyclin-dependent kinase-4, cyclin-dependent kinase-6, cyclin D1, and phospho-retinoblastoma protein, and an increase of p27 and p18 proteins were observed. Intriguingly, KG-135 increased the tumor suppressor FOXO3a and induced the accumulation of autophagy hallmark LC3-II and acidic vesicular organelles without an increase of the upstream marker Beclin-1. Unconventionally, the autophagy adaptor protein p62 (sequestosome 1) was increased rather than decreased. Blockade of autophagy by hydroxychloroquine dramatically potentiated KG-135-induced FOXO3a and its downstream (FasL) ligand accompanied by the cleavage of caspase-8. Meanwhile, the decrease of Bcl-2 and survivin, as well as the cleavage of caspase-9, were also drastically enhanced, resulting in massive apoptosis. Conclusion: Besides arresting the cells in G1 phase, KG-135 increased FOXO3a and induced an unconventional autophagy in A549 cells. Both the KG-135-activated extrinsic FOXO3a/FasL/caspase-8 and intrinsic caspase-9 apoptotic pathways were potentiated by blockade of autophagy. Combination of KG-135 and autophagy inhibitor may be a novel strategy as an integrative treatment for cancers.

• Journal of Life Science
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• v.16 no.4
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• pp.589-597
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• 2006

Genistein, a natural isoflavonoid phytoestrogen, is a strong inhibitor of protein tyrosine kinase and DNA topoisomerase activities. There are several studies documenting molecular alterations leading to cell cycle arrest and induction of apoptosis by genistein as a chemopreventive agent in a variety of cancer cell lines; however, its mechanism of action and its molecular targets on human bladder carcinoma and leukemic cells remain unclear. In the present study, we have addressed the mechanism of action by which genistein suppressed the proliferation of T24 bladder carcinoma and U937 leukemic cells. Genistein significantly inhibited the cell growth and induced morphological changes, and induced the G2/M arrest of the cell cycle in both T24 and U937 cells with a relatively stronger cytotoxicity in U937. The G2/M arrest in T24 cells was associated with the inhibition of cyclin A, cyclin B1 and Cdc25C protein expression without alteration of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21(WAF1/CIP1). However, the inhibitory effects of genistein on the cell growth of U937 cells were connected with a marked inhibition of cyclin B1 and an induction of Cdk inhibitor p21 proteins by p53-independent manner. These data suggest that genistein may exert a strong anticancer effect and additional studies will be needed to evaluate the different mechanisms between T24 and U937 cells.

• Nutrition Research and Practice
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• v.12 no.2
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• pp.129-134
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• 2018

BACKGROUND/OBJECTIVES: Although several recent studies have reported the anti-cancer effects of extracts or components of Citrus unshiu peel, which has been used for various purposes in traditional medicine, the molecular mechanisms for their effects remain unclear. In the present study, the anti-cancer activity of a water-soluble extract of C. unshiu peel (WECU) in MDA-MB-231 human breast carcinoma cells at the level of apoptosis induction was investigated. MATERIALS/METHODS: Cytotoxicity was evaluated using the MTT assay. Apoptosis was detected using DAPI staining and flow cytometry analyses. Mitochondrial membrane potential, reactive oxygen species (ROS) assay, caspase activity and Western blotting were used to confirm the basis of apoptosis. RESULTS: The results indicated that WECU-induced apoptosis was related to the activation of caspase-8, and -9, representative initiator caspases of extrinsic and intrinsic apoptosis pathways, respectively, and caspase-3 accompanied by proteolytic degradation of poly(ADP-ribose) polymerase and down-regulation of the inhibitors of apoptosis protein family members. WECU also increased the pro-apoptotic BAX to anti-apoptotic BCL-2 ratio, loss of mitochondrial membrane potential and cytochrome c release from mitochondria to cytoplasm. Furthermore, WECU provoked the generation of ROS, but the reduction of cell viability and induction of apoptosis by WECU were prevented when ROS production was blocked by antioxidant N-acetyl cysteine. CONCLUSIONS: These results suggest that WECU suppressed proliferation of MDA-MB-231 cells by activating extrinsic and intrinsic apoptosis pathways in a ROS-dependent manner.

• Parasites, Hosts and Diseases
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• v.54 no.1
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• pp.9-14
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• 2016

Tamoxifen is an antagonist of the estrogen receptor and currently used for the treatment of breast cancer. The current treatment of cutaneous leishmaniasis with pentavalent antimony compounds is not satisfactory. Therefore, in this study, due to its antileishmanial activity, effects of tamoxifen on the growth of promastigotes and amastigotes of Leishmania major Iranian strain were evaluated in vitro. Promastigotes and amastigotes were treated with different concentrations (1, 5, 10, 20, and $50{\mu}g/ml$) and time periods (24, 48, and 72 hr) of tamoxifen. After tamoxifen treatment, MTT assay (3-[4,5-dimethylthiazol-2-yl]-2,5 biphenyl tetrazolium bromide assay) was used to determine the percentage of live parasites and Graph Pad Prism software to calculate $IC_{50}$. Flow cytometry was applied to investigate the induction of tamoxifen-induced apoptosis in promastigotes. The half maximal inhibitory concentration ($IC_{50}$) of tamoxifen on promastigotes was $2.6{\mu}g/ml$ after 24 hr treatment. Flow cytometry analysis showed that tamoxifen induced early and late apoptosis in Leishmania promastigotes. While after 48 hr in control group the apoptosis was 2.0%, the $50{\mu}g/L$ concentration of tamoxifen increased it to 59.7%. Based on the in vitro antileishmanial effect, tamoxifen might be used for leishmaniasis treatment; however, further researches on in vivo effects of tamoxifen in animal models are needed.

• Korean Journal of Medicinal Crop Science
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• v.17 no.5
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• pp.341-345
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• 2009

Cerebral ischemia results from a transient or permanent reduction in cerebral blood flow that decreases oxygen and glucose supply. When the cellular oxygen supply is reduced to critical level, damage to cells and induction of cell death are occurred by excitotoxicity, oxidative stress and inflammation. Ischemia remains one of the leading causes of death, but there is no effective treatment that might protect neurons gainst ischemia by interrupting the cascade of cell death. In this study, human neuroblastoma SH-SY5Y cells are exposed to oxygen and glucose deprivation (OGD) followed by reoxgenation. OGD can mimic the acute restriction of metabolite and oxygen supply caused by ischemia and is widely used as a model of ischemic conditions. SH-SY5Y cells are treated samples at the commencement of OGD to achieve different final concentrations, and cell viabilities were quantified using the measurement of flow cytometry analysis. Of those tested, the extracts of Polygala tenuifolia (roots), Dictamnus dasycarpus (barks), Polygala tenuifolia (roots), Eucommia ulmoides (branches), Eucommia ulmoides (barks), Poria cocos (whole), Sophora flavescens (roots) showed neuroprotective effects, with $EC_{50}$ values of $4.5{\pm}0.6$, $7.9{\pm}1.5$, $10.5{\pm}0.7$, $18.4{\pm}1.9$, $19.6{\pm}0.3$, $21.6{\pm}1.9$, and $30.7{\pm}3.9{\mu}g/m{\ell}$, respectively.

• Environmental Mutagens and Carcinogens
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• v.24 no.1
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• pp.1-9
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• 2004

Three D-type cyelins (D1, D2, and D3) are expressed in G1 phase of the cell cyele and have been implicated in cell transformation and neoplasia in human and mouse. Cyclin D1 overexpression or amplification was described in various human cancers. However, there is controversy about the role of cyclin D2 in cell cyele progression and human carcinogenesis. Specially, loss of cyelin D2 is involved in a vital tumor suppressor function in normal breast tissue, and that its loss may be related to tumorigenesis. The author examined to effect over-expression of cyclin D2 on the cell proliferation, apoptosis, and cell cycle using cyclin D2 transfected stable T47D breast cancer cells to investigate whether cyclinD2 functions as a positive regulator or negative regulator in cell proliferation. Overexpression of cyclin D2 led to the suppression of cell growth in cyclin D2 transfected T47D in both in its expression level and a time dependent manner with up to 50% reduction of cell growth at 72 hours. Therefore, the authors performed the cell cycle phase analysis using the flow cytometry to investigate the effect of cyclin D2 on the cell cycle phase in cyclin D2 transfected stable T47D cells. The flow cytometry analysis revealed increased sub G0 phase in cyclin D2 transfeted cells up to 23% at 72 hours. To confirm these results induced by overexpression of cyclinD2, the apoptotic bodies were counted in control and cyclin D2 transfected T47 cells. There are markedly increases of apoptotic bodies in cyclin D2-transfected cells up to 18%. These results suggested that Cyclin D2 suppresses the cell proliferation in breast cancers cells via the induction of apotosis.