• Development and Reproduction
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• v.12 no.3
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• pp.297-303
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• 2008

BCL-2 family members are essential protein for the regulation of cell death and survival consisting both antiapoptotic and pro-apoptotic proteins. In the present study, we designed and cloned a new apoptotic molecule MCL-1ES BH3M coding a modified protein of MCL-1L. Compared to MCL-1L protein, MCL-1ES BH3M lacks the PEST motifs known to be involved in MCL-1L protein degradation and has seven mutated residues in BH3 domain critical for dimerization with BCL-2 family members. Overexpression of MCL-1ES BH3M induced death of different cells, and its cell killing effect was not blocked by forced expression of the pro-survival protein MCL-1L. Expression of MCL-1ES BH3M protein led to the activation of caspase 9 and caspase 3, suggesting apoptotic cell death, and confocal fluorescent microscopic analyses showed that MCL-1ES BH3M was partially localized in mitochondria. In conclusion, we reported a new apoptotic molecule and determined its cell death activity in cells.

• Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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• v.7 no.1
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• pp.395-405
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• 2017

To confirm potential anti-cancer activities of ethylacetate (EtOAc) fraction from Orostachys japonicus on the A549 human lung cancer cells, this study examined. As a result of conducting MTS assay for measuring cell viability, the EtOAc fraction inhibited the proliferation of A549 cells in a dose-dependent manner. To investigate whether the inhibiting A549 cell viability was caused by apoptosis, this study analyzed chromatin condensation in A549 cells using DAPI staining. The morphological changes such as the formation of nuclear condensation were formed in a dose-dependent manner. Also, this study performed Annexin V-FITC staining for detecting phosphatidylinositol (PS). As a result of Annexin V-FITC staining to investigate level of early and late apoptosis, the apoptosis level treated with EtOAc fraction was higher than that of control. RT-PCR was performed to study the correlation between G2/M cell cycle arrest and cell cycle control genes. The anti-cancer activity of EtOAc fraction was accompanied by inhibition of CDK1, 4, cyclin B1 and D1 mRNA. This study also examined the expression of various marker proteins: p53, Bax, Bcl-2 and pro-caspase 3. Western blotting revealed that p53 and Bax proteins were up-regulated, and Bcl-2 and pro-caspase 3 proteins down-regulated in a time and dose-dependent manner.

• Korean Journal of Clinical Laboratory Science
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• v.56 no.1
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• pp.73-84
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• 2024

A pulsed electromagnetic field (PEMF) enhances the efficacy of several anticancer drugs. Doxorubicin (DOX) is an anticancer agent used to treat various malignancies, including breast cancer. This study examined whether a PEMF increases the anticancer effect of DOX on MCF-7 human breast cancer cells and elucidated the underlying mechanisms affected by PEMF stimulation in DOX-treated MCF-7 human breast cancer cells. A cotreatment with DOX and a PEMF potentiated the reduction in MCF-7 cell viability compared to the treatment with DOX alone. The PEMF elevated DOX-induced G1 arrest by affecting cyclin-dependent kinase 2 phosphorylation and the expression of G1 arrest-related molecules, including p53, p21, cyclin E2, and polo like kinase 1. In addition, PEMF increased the DOX-induced upregulation of proapoptotic proteins, such as Fas and Bcl-2-associated X, and the downregulation of antiapoptotic proteins, including myeloid leukemia 1 and survivin. PEMF promoted the DOX-induced activation of caspases-8, -9, and -7 and poly (adenosine diphosphate-ribose) polymerase cleavage in MCF-7 cells. In conclusion, PEMF enhances the anticancer activity in DOX-treated MCF-7 breast cancer cells by increasing G1 cell cycle arrest and caspase-dependent apoptosis. These findings highlight the potential use of a PEMF as an adjuvant treatment for DOX-based chemotherapy against breast cancer.

• Biomolecules & Therapeutics
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• v.26 no.4
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• pp.399-408
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• 2018

In this study, we examined the molecular and functional characterization of choline uptake in the human esophageal cancer cells. In addition, we examined the influence of various drugs on the transport of [$^3H$]choline, and explored the possible correlation between the inhibition of choline uptake and apoptotic cell death. We found that both choline transporter-like protein 1 (CTL1) and CTL2 mRNAs and proteins were highly expressed in esophageal cancer cell lines (KYSE series). CTL1 and CTL2 were located in the plasma membrane and mitochondria, respectively. Choline uptake was saturable and mediated by a single transport system, which is both $Na^+$-independent and pH-dependent. Choline uptake and cell viability were inhibited by various cationic drugs. Furthermore, a correlation analysis of the potencies of 47 drugs for the inhibition of choline uptake and cell viability showed a strong correlation. Choline uptake inhibitors and choline deficiency each inhibited cell viability and increased caspase-3/7 activity. We conclude that extracellular choline is mainly transported via a CTL1. The functional inhibition of CTL1 by cationic drugs could promote apoptotic cell death. Furthermore, CTL2 may be involved in choline uptake in mitochondria, which is the rate-limiting step in S-adenosylmethionine (SAM) synthesis and DNA methylation. Identification of this CTL1- and CTL2-mediated choline transport system provides a potential new target for esophageal cancer therapy.

• The Korean Journal of Pain
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• v.25 no.4
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• pp.213-220
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• 2012

Background: It has been demonstrated that the expression of tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) and apoptotic cell death in the dorsal root ganglion (DRG) following spinal nerve constriction injury play a role in the initiation and continuation of hyperalgesia and allodynia. The present study was designed to investigate the effects of ethyl pyruvate (EP) on mechanical and cold allodynia, TNF-${\alpha}$ expression, and apoptosis in DRG after spinal nerve ligation injury. Methods: Rats were divided into 3 groups: control, pre-EP, and post-EP. EP (50 mg/kg) was intraperitoneally injected 30 minutes before (pre-EP) or after (post-EP) surgery. Behavioral tests to determine mechanical and cold allodynia were conducted before surgery and 4 and 7 days after surgery. Seven days after surgery, TNF-${\alpha}$ protein levels in DRG were evaluated by enzyme-linked immunosorbent assay, and DRG apoptosis was determined by immunohistochemical detection of activated caspase-3. Results: Treatment with EP significantly reduced mechanical and cold allodynia following spinal nerve ligation injury. TNF-${\alpha}$ protein levels in the pre-EP ($4.7{\pm}1.2$ pg/200 ${\mu}g$; P < 0.001) and post-EP ($6.4{\pm}1.8$ pg/200 ${\mu}g$; P < 0.001) groups were 2-3 times lower than the control group ($14.4{\pm}1.2$ pg/200 ${\mu}g$). The percentages of neurons and satellite cells that co-localized with caspase-3 were also significantly lower in the pre-EP and post-EP groups than the control group. Conclusions: These results demonstrate that EP has a strong anti-allodynic effect that acts through the inhibition of TNF-${\alpha}$ expression and apoptosis in DRG after spinal nerve ligation injury.

• BMB Reports
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• v.53 no.8
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• pp.419-424
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• 2020

Bee venom (BV), secreted from the venom gland of the honey bee, contains several biological active compounds. BV has been widely used as a traditional medicine for treating human disease, including cancer. In this study, we have shown the molecular mechanism underlying the therapeutic effect of BV on cancer. Treatment with BV reduced the proliferation of cervical-cancer cells in a dose- and time-dependent manner. Interestingly, the killing effect of BV was specific to HPV-positive cervical-cancer cell lines, such as Caski and HeLa cells, and not to HPV-negative cervical-cancer cells (C33A). BV reduced the expression of HPV E6 and E7 at RNA and protein levels, leading to an increase in the expression of p53 and Rb in Caski and HeLa cells. Further, BV decreased the levels of cell-cycle proteins, such as cyclin A and B, and increased the levels of cell-cycle inhibitors, such as p21 and p27. BV significantly induced apoptosis and inhibited wound healing and migration of cervical-cancer cells. It also upregulated the expression of pro-apoptotic BAX and downregulated the expression of anti-apoptotic Bcl-2 and Bcl-XL. Cleavage of caspase-3, caspase-9, and PARP were also induced by BV treatment, whereas the phosphorylation of mitogenic signaling-related proteins, such as AKT, JNK, p38, and ERK, were downregulated. Our results indicate that BV has a therapeutic selectivity for HPV-positive malignant cells, so further clinical studies are needed to assess its clinical application.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.7
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• pp.4249-4254
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• 2013

Background: Parafibromin is a protein encoded by the HRPT2 (hyperparathyroidism 2) oncosuppressor gene and its down-regulated expression is involved in pathogenesis of parathyroid, breast, gastric and colorectal carcinomas. This study aimed to clarify the effects of parafibromin expression on the phenotypes and relevant mechanisms of DLD-1 colon carcinoma cells. Methods: DLD-1 cells transfected with a parafibromin-expressing plasmid were subjected to examination of phenotype, including proliferation, differentiation, apoptosis, migration and invasion. Phenotype-related proteins were measured by Western blot. Parafibromin and ki-67 expression was detected by immunohistochemistry on tissue microarrays. Results: The transfectants showed higher proliferation by CCK-8, better differentiation by electron microscopy and ALP activity and more apoptotic resistance to cisplatin by DNA fragmentation than controls. There was no difference in early apoptosis by annexin V, capase-3 activity, migration and invasion between DLD-1 cells and their transfectants. Ectopic parafibromin expression resulted in down-regulated expression of smad4, MEKK, GRP94, GRP78, $GSK3{\beta}$-ser9, and Caspase-9. However, no difference was detectable in caspase-12 and -8 expression. A positive relationship was noted between parafibromin and ki-67 expression in colorectal carcinoma. Conclusions: Parafibromin overexpression could promote cell proliferation, apoptotic resistance, and differentiation of DLD-1 cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3103-3107
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• 2012

Osteosarcoma, the most common primary mesenchymal malignant tumor, usually has bad prognosis in man, with cancer stem-like cells (CSCs) considered to play a critical role in tumorigenesis and drug-resistance. It is known that phosphatidylinositol 3-kinase (PI3K) is involved in regulation of tumor cell fates, such as proliferation, cell cycling, survival and apoptosis. Whether and how PI3K and inhibitors might cooperate in human osteosarcoma CSCs is still unknown. We therefore evaluated the effects of LY294002, a PI3K inhibitor, on the cell cycle and apoptosis of osteosarcoma CSCs in vitro. LY294002 prevented phosphorylation of protein kinase B (PKB/Akt) by inhibition of PI3K phosphorylation activity, thereby inducing G0/G1 cell cycle arrest and apoptosis in osteosarcoma CSCs. Further studies also demonstrated that apoptosis induction by LY294002 is accompanied by activation of caspase-9, caspase-3 and PARP, which are involved in the mitochondrial apoptosis pathway. Therefore, our results indicate PI3K inhibitors may represent a potential strategy for managing human osteosarcoma via affecting CSCs.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.7
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• pp.3471-3476
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• 2012

Background and Objective: Histone deacetylase (HDAC) inhibitors represent a promising class of potential anticancer agents for treatment of human malignancies. In this study, we investigated the effect of trichostatin A (TSA), one such HDAC inhibitor, in combination with docetaxel (TXT), a cytotoxic chemotherapy agent or erlotinib, a novel molecular target therapy drug, on lung cancer A549 cells. Methods: A549 cells were treated with TXT, erlotinib alone or in combination with TSA, respectively. Cell viability, apoptosis, and cell cycle distribution were evaluated using MTT (3- (4, 5-dimethylthiazol-2-yl) -2, 5-diphenyltetrazolium bromide) assay, Hochst33258 staining and flow cytometry. Moreover, immunofluorescent staining and Western blot analysis were employed to examine alterations of ${\alpha}$-tubulin, heat shock protein 90 (hsp90), epidermal growth factor receptor (EGFR), and caspase-3 in response to the different exogenous stimuli. Results: Compared with single-agent treatment, co-treatment of A549 cells with TSA/TXT or TSA/erlotinib synergistically inhibited cell proliferation, induced apoptosis, and caused cell cycle delay at the $G_2/M$ transition. Treatment with TSA/TXT or TSA/erlotinib led to a significant increase of cleaved caspase-3 expression, also resulting in elevated acetylation of ${\alpha}$-tubulin or hsp90 and decreased expression of EGFR, which was negatively associated with the level of acetylated hsp90. Conclusions: Synergistic anti-tumor effects are observed between TXT or erlotinib and TSA on lung cancer cells. Such combinations may provide a more effective strategy for treating human lung cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.4
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• pp.1947-1959
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• 2016

Background: Colorectal cancer (CRC) is a major cause of morbidity and mortality, being the second most common type of cancer worldwide in both men and women. It accounts yearly for approximately 9% of all new cases of cancers. Furthermore, the current chemotherapeutic regimens seem unsatisfactory, so that exploration of novel therapeutic modalities is needed. The present study was undertaken to investigate the inhibitory effects of a crude alkaloid extract (CAERS) of a medicinal herb, Rhazya stricta, on proliferation of CRC HCT116 cells and to elucidate mechanisms of action. To achieve these aims, we utilized MTT, comet, DNA laddering and gene reporter assays, along with Western blot and RT-PCR analyses. Results: We found that CAERS inhibited cell proliferation and induced apoptotic cell death in HCT116 cells. Hallmarks of morphological and biochemical signs of apoptosis were clearly evident. CAERS down-regulated DNA-binding and transcriptional activities of NF-${\kappa}B$ and AP-1 proteins, while up-regulating expression of the Nrf-2 protein. It also down-regulated expression levels of the ERK MAPK, Bcl-2, cyclin D1, CDK-4, survivin and VEGF and up-regulated levels of Bax, caspase-3/7 and -9, p53, p21, Nrf-2. Markedly, it promoted mRNA expression levels of cytoprotective genes including the hemeoxygenase-1, NAD(P)H quinine oxidoreductase 1 and UDP-glucuronyltransferase. Conclusions: These findings indicate that CAERS exerts antiproliferative action on CRC cells through induction of apoptotic mechanisms, and suggest CAERS could be a promising agent for studying and developing novel chemotherapeutic agents aimed at novel molecular targets for the treatment of CRC.