• BMB Reports
• /
• 제53권8호
• /
• pp.419-424
• /
• 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
• /
• 제15권4호
• /
• pp.1757-1762
• /
• 2014

Development of drugs from natural products has been undergoing a gradual evoluation. Many plant derived compounds have excellent therapeutic potential against various human ailments. They are important sources especially for anticancer agents. A number of promising new agents are in clinical development based on their selective molecular targets in the field of oncology. D-pinitol is a naturally occurring compound derived from soy which has significant pharmacological activitites. Therefore we selected D-pinitol in order to evaluate apoptotic potential in the MCF-7 cell line. Human breast cancer cells were treated with different concentrations of D-pinitol and cytotoxicity was measured by MTT and LDH assays. The mechanism of apoptosis was studied with reference to expression of p53, Bcl-2, Bax and NF-kB proteins. The results revealed that D-pinitol significantly inhibited the proliferation of MCF-7 cells in a concentration-dependent manner, while upregulating the expression of p53, Bax and down regulating Bcl-2 and NF-kB. Thus the results obtained in this study clearly vindicated that D-pinitol induces apotosis in MCF-7 cells through regulation of proteins of pro- and anti-apoptotic cascades.

• 생명과학회지
• /
• 제21권8호
• /
• pp.1109-1119
• /
• 2011

예로부터 한국, 일본 및 중국에서 민간처방 약재 및 건강식품으로 사용되어온 매실은 다양한 효능을 가지는 것으로 알려져 있으나 인체 암세포에서 유발하는 항암작용 및 그에 따른 분자생물학적 기작에 대해서는 명확히 밝혀져 있지 않다. 본 연구에서는 인체 혈구암 U937 세포에서 매실의 메탄올 추출물(MEPM)이 유발하는 항암효과 및 항암기전을 조사한 결과, MEPM 처리 농도 의존적으로 암세포의 성장억제 및 apoptosis를 유발하는 것으로 나타났다. MEPM에 의해서 유발되는 apoptosis에는 XIAP 및 survivin 등과 같은 IAP family의 발현 감소와 더불어 FasL의 발현 증가, Bcl-2의 발현 감소 및 Bid의 단편화 현상이 관여하는 것으로 나타났으며, 두 가지 apoptosis 유발 개시 및 최종 apoptosis 단계에서 중요한 역할을 하는 caspase-8과 -9 및 -3의 활성화와 그에 따른 다양한 기질단백질의 발현 감소 및 단편화가 동반되었음을 알 수 있었다. 또한 인위적인 caspase-3의 활성 차단으로 MEPM에 의하여 유발되는 apoptosis가 현저하게 억제되는 것으로 나타났다. 이상의 결과에서 MEPM은 암세포의 chemotherapeutic agent로서의 가능성을 확인하였지만 향후 지속적인 연구를 통하여 활성물질의 동정 및 관련 기전의 비교 등이 지속적으로 이루어져야 할 것으로 생각된다.

• Reproductive and Developmental Biology
• /
• 제36권3호
• /
• pp.167-172
• /
• 2012

The key regulators of apoptosis are the interacting protein of the Bcl-2 family. Bcl-2, an important member of this family, blocks cytochrome C release by sequestering pro-apoptotic BH3-only proteins such as Bid, Bad, Bax and Bim. The pro-survival family members (Bcl-2, Bcl-XL, Bcl-W) are critical for cell survival, since loss of any of them causes cell death in certain cell type. However, its role during early porcine embryonic development is not sufficient. In this study, we traced the effects of Bcl-2 inhibitor, ABT-737, on early porcine embryonic development. We also investigated several indicators of developmental potential, including gene expression (apoptosis-related genes) and apoptosis, which are affected by ABT-737. Porcine embryos were cultured in the PZM-3 medium with or without ABT-737 for 6 days. In result, significant differences in developmental potential were detected between the embryos that were cultured with or without ABT-737 ($14.7{\pm}3.0$ vs $30.3{\pm}4.8%$, p<0.05). TUNEL assay showed that the number of containing fragmented DNA at the blastocyst stage increased in the ABT-737 treated group compared with control (4.7 vs 3.7, p<0.05). The mRNA expression of the pro-apoptotic gene Bax increased in ABT-737 treated group (p<0.05), whereas expressions of the anti-apoptotic Bcl-2 family members (Bcl-2, Bcl-XL, Bcl-W) decreased (p<0.05). Also, expressions of the ER stress indicator genes (GRP78, XBP-1 and sXBP-1) increased in ABT-737 treated group (p<0.05). In conclusion, Bcl-2 is closely associated with of apoptosis- and ER stress-related genes expressions and developmental potential in pig embryos.

• Biomolecules & Therapeutics
• /
• 제23권2호
• /
• pp.128-133
• /
• 2015

Although coffee is known to have antioxidant, anti-inflammatory, and antitumor properties, there have been few reports about the effect and mechanism of coffee compounds in colorectal cancer. Heat shock proteins (HSPs) are molecular chaperones that prevent cell death. Their expression is significantly elevated in many tumors and is accompanied by increased cell proliferation, metastasis and poor response to chemotherapy. In this study, we investigated the cytotoxicity of four bioactive compounds in coffee, namely, caffeine, caffeic acid, chlorogenic acid, and kahweol, in HT-29 human colon adenocarcinoma cells. Only kahweol showed significant cytotoxicity. Specifically, kahweol increased the expression of caspase-3, a pro-apoptotic factor, and decreased the expression of anti-apoptotic factors, such as Bcl-2 and phosphorylated Akt. In addition, kahweol significantly attenuated the expression of HSP70. Inhibition of HSP70 activity with triptolide increased kahweol-induced cytotoxicity. In contrast, overexpression of HSP70 significantly reduced kahweol-induced cell death. Taken together, these results demonstrate that kahweol inhibits colorectal tumor cell growth by promoting apoptosis and suppressing HSP70 expression.

• 생명과학회지
• /
• 제29권7호
• /
• pp.809-816
• /
• 2019

p-Coumaric acid (p-CA)는 항산화 및 항염 활성을 가진 식물계에서 가장 풍부한 식물화학물질이다. 그러나 위암세주포에서 p-CA의 항암 활성과 전사체 발현에 대한 연구는 아직까지 수행된 바 없다. 본 연구에서는 SNU-16 위암세포에서 p-CA에 의한 세포 증식 억제 및 전사체 프로파일에 미치는 영향을 조사하였다. p-CA는 세포사멸 단백질 발현을 조절하여 SNU-16 세포에서의 세포사멸을 유도하였다. RNA-seq 분석을 사용하여 p-CA처리에 의해 SNU-16 세포에서 차별적으로 발현된 유전자(DEGs)를 동정하였다. DEGs들의 gene ontology (GO) 술어로 유전자 산물을 검색한 결과, 주로 염증반응, 세포사멸 과정, 세포주기 및 면역 반응에 관여하는 생물학적 과정에 관여하는 것으로 나타났다. 또한, KEGG 경로분석 결과, p-CA는 주로 PI3K-Akt 와 암 신호전달 경로에 변화를 유발하였다. 본 연구결과는 p-CA가 세포증식과 암 신호 전달 경로에 관여하는 유전자 발현을 조절함으로써 위암 예방 효과를 나타낼 수 있음을 시사한다.

• 생명과학회지
• /
• 제16권5호
• /
• pp.716-722
• /
• 2006

Superoxide dismutase (SOD) is physiologically important in regulating cellular homeostasis and apoptotic cell death, and its mutations are the cause of familial amyotrophic lateral sclerosis (FALS). Mitochondrial serine protease HtrA2 has a pro-apoptotic function and has known to be associated with neurodegenerative disorders. To investigate the relationship between genes associated with apoptotic cell death, such as HtrA2 and SOD1, we utilized the pGEX expression system to develop a simple and rapid method for purifying wild-type and ALS-associated mutant SOD1 proteins in a suitable form for biochemical studies. We purified SOD1 and SOD1 (G93A) proteins to approximately 90% purity with relatively high yields (3 mg per liter of culture). Consistent with the result in mammalian cells, SOD1 (G93A) was more insoluble than wild-type SOD1 in E. coli, indicating that research on the aggregate formation of SOD1 may be possible using this pGEX expression system in E. coli. We investigated the HtrA2 serine protease activity on SOD1 to assess the relationship between two proteins. Not only wild-type SOD1 but also ALS-associated mutant SOD1 (G93A) were cleaved by HtrA2, resulting in the production of the 19 kDa and 21 kDa fragments that were specific for anti-SOD1 antibody. Using protein gel electrophoresis and immunoblot assay, we compared the relative molecular masses of thrombin-cleaved GST-SOD1 and HtrA2-cleaved SOD1 fragments and can predict that the HtrA2-cleavage sites within SOD1 are the peptide bonds between leucine 9-lysine 10 (L9-K10) and glutamine 23-lysine 24 (Q23-K24). Our study indicates that SOD1 is one of the substrate for HtrA2, suggesting that both HtrA2 and SOD1 may be important for modulating the HtrA2-SOD1-mediated apopotic cell death that is associated with the pathogenesis of neurodegenerative disorder.

• Molecules and Cells
• /
• 제38권6호
• /
• pp.518-527
• /
• 2015

Controlled release of medications remains the most convenient way to deliver drugs. In this study, we precipitated gold nanoparticles with quercetin. We loaded gold-quercetin into poly(DL-lactide-co-glycolide) nanoparticles (NQ) and tested the biological activity of NQ on HepG2 hepatocarcinoma cells to acquire the sustained release property. We determined by circular dichroism spectroscopy that NQ effectively caused conformational changes in DNA and modulated different proteins related to epigenetic modifications and c ell cycle control. The mitochondrial membrane potential (MMP), reactive oxygen species (ROS), cell cycle, apoptosis, DNA damage, and caspase 3 activity were analyzed by flow cytometry, and the expression profiles of different anti- and pro-apoptotic as well as epigenetic signals were studied by immunoblotting. A cytotoxicity assay indicated that NQ preferentially killed cancer cells, compared to normal cells. NQ interacted with HepG2 cell DNA and reduced histone deacetylases to control cell proliferation and arrest the cell cycle at the sub-G stage. Activities of cell cycle-related proteins, such as $p21^{WAF}$, cdk1, and pAkt, were modulated. NQ induced apoptosis in HepG2 cells by activating p53-ROS crosstalk and induces epigenetic modifications leading to inhibited proliferation and cell cycle arrest.

• 생명과학회지
• /
• 제23권9호
• /
• pp.1118-1125
• /
• 2013

감귤류에 많이 함유되어 있는 naringenin은 항암화학요법제로서 중요한 가능성을 가지고 있으나 항암활성에 대한 분자생물학적 기전에 대해서는 명확히 밝혀져 있지 않다. 본 연구에서는 인체 혈구암세포인 U937 세포에서 naringenin이 유발하는 항암효과 및 항암기전을 조사하였다. Naringenin 처리에 의한 U937 세포의 증식억제는 apoptosis 유발과 연관성이 있었으며, 이러한 현상은 caspases 활성화와 밀접한 관련이 있었다. 그러나 pan-caspase inhibitor인 z-VAD-fmk의 선처리에 의하여 U937 세포에서 naringenin이 유발하는 apoptosis가 억제되는 것으로 나타났으므로 caspases가 apoptosis 유발의 중요한 조절자라는 것을 알 수 있었다. 또한 U937 세포에 naringenin을 처리하였을 경우 pro-apoptotic Bcl-2 및 anti-apoptotic Bax의 발현에는 아무런 변화가 나타나지는 않았지만 Bcl-2가 과발현된 U937/Bcl-2 세포에서 naringenin에 의한 apoptosis가 억제되었다. 하지만 small-molecule Bcl-2 inhibitor인 HA14-1 및 naringenin을 같이 처리하였을 경우에는 XIAP 발현감소, Bid 단편화 및 caspase-3 활성화를 통하여 다시 apoptosis가 유발되었다. 따라서 HA14-1 및 naringenin에 의한 apoptosis 상승효과는 death receptor-mediated apoptosis pathway를 경유한다는 것을 제시하는 결과이다.

• 생명과학회지
• /
• 제23권7호
• /
• pp.926-932
• /
• 2013

글루타민과 혈청은 세포의 생존과 증식에 기본적으로 요구되지만, 그들의 양적 변화에 따른 내피세포 반응에 관한 신호전달 관련 연구는 거의 이루어지지 않았다. 본 연구에서는 인체 재대정맥 내피세포(human umbilical vein endothelial cells, HUVECs)의 증식에 미치는 글루타민과 혈청의 결핍에 관한 영향을 조사하였다. 본 연구의 결과에 의하면 글루타민 및 혈청이 결핍된 조건에서 배양된 HUVECs의 증식 억제는 apoptosis 유발과 연관성이 있었음을 DAPI staining에 의한 핵의 형태 변화와 유세포 분석을 통하여 확인하였다. 비록 혈청이 결핍된 조건보다 글루타민 결핍에 의한 apoptosis 유발 정도가 더 높게 나타났으나, 두 현상에 의한 apoptosis의 유발은 anti-apoptotic Bcl-2 및 Bcl-xL의 발현 저하와 pro-apoptotic Bax의 발현 증가, IAP family 단백질의 발현 감소, caspase의 활성 증가에 따른 PARP 단백질의 단편화와 연관성이 있었다. 또한 이러한 조건에서 HUVECs의 Bid 발현의 감소 또는 tBid 발현의 증가 현상이 관찰되어, 글루타민 또는 혈청 결핍에 의한 HUVECs의 apoptosis 유발은 세포막 수용체 및 미토콘드리아 활성 경로를 동시에 통하여 이루어지고 있음을 알 수 있었다. 그러나 글루타민과 혈청이 동시에 결핍된 조건에서 배양된 HUVECs의 증식 억제 현상은 각각의 조건에 비하여 증가되었으나 apoptosis는 유발되지 않았다.