Induction of Intrinsic and Extrinsic Apoptosis Pathways in the Human Leukemic MOLT-4 Cell Line by Terpinen-4-ol

Khaw-On, Patompong,Banjerdpongchai, Ratana Asian Pacific Journal of Cancer Prevention 2012 Asian Pacific journal of cancer prevention Vol.13 No.7

Terpinen-4-ol is a terpene found in the rhizome of Plai (Zingiber montanum (Koenig) Link ex Dietr.). In this study apoptogenic activity and mechanisms of cell death induced by terpinen-4-ol were investigated in the human leukemic MOLT-4 cell line. Terpinen-4-ol exhibited cytotoxicity in MOLT-4 cells, with characteristic morphological features of apoptosis by Wright's staining. The mode of cell death was confirmed to be apoptosis by flow cytometric analysis after staining with annexin V-FITC and propidium iodide. A sub-G1 peak in DNA histograms of cell cycle assays was observed. Terpinen-4-ol induced-MOLT-4 cell apoptosis mediated through an intrinsic pathway involving the loss of mitochondrial transmembrane potential (MTP) and release of cytochrome c into the cytosol. In addition, terpinen-4-ol also induced apoptosis via an extrinsic pathway by caspase-8 activation resulting in the cleavage of cytosolic Bid. Truncated-Bid (tBid) translocated to mitochondria and activated the mitochondrial pathway in conjunction with down-regulation of Bcl-2 protein expression. Caspase-3 activity also increased. In conclusion, terpinen-4-ol can induce human leukemic MOLT-4 cell apoptosis via both intrinsic and extrinsic pathways.

Butyrylcholinesterase Inhibitory Activity and GC-MS Analysis of Carica papaya Leaves

Kooi-Yeong Khaw,Nelson Jeng Yeou Chear,Sathiya Maran,Keng Yoon Yeong,Yong Sze Ong,Bey Hing Goh 한국생약학회 2020 Natural Product Sciences Vol.26 No.2

Carica papaya is a medicinal and fruit plant owing biological activities including antioxidant, antiviral, antibacterial and anticancer. The present study aims to investigate the acetyl (AChE) and butyryl (BChE) cholinesterase inhibitory potentials of C. papaya extracts as well as their chemical compositions. The chemical composition of the active extract was identified using a gas chromatography-mass spectrometry (GC-MS). Ellman enzyme inhibition assay showed that the alkaloid-enriched leaf extract of C. papaya possessed significant anti-BChE activity with an enzyme inhibition of 75.9%. GC-MS analysis showed that the alkaloid extract composed mainly the carpaine (64.9%) – a major papaya alkaloid, and some minor constituents such as aliphatic hydrocarbons, terpenes and phenolics. Molecular docking of carpaine revealed that this molecule formed hydrogen bond and hydrophobic interactions with choline binding site and acyl pocket. This study provides some preliminary findings on the potential use of C. papaya leaf as an herbal supplement for the prevention and treatment of Alzheimer’s disease.

Garcinexanthone G, a Selective Butyrylcholinesterase Inhibitor from the Stem Bark of Garcinia atroviridis

Kooi-Yeong Khaw,Vikneswaran Murugaiyah,Melati Khairuddean,Wen-Nee Tan 한국생약학회 2018 Natural Product Sciences Vol.24 No.2

The present study was undertaken to investigate the isolated compounds from the stem bark of Garcinia atroviridis as potential cholinesterase inhibitors and the ligand-enzyme interactions of selected bioactive compounds in silico. The in vitro cholinesterase results showed that quercetin (3) was the most active AChE inhibitor (12.65 ? 1.57 ?g/ml) while garcinexanthone G (6) was the most active BChE inhibitor (18.86 ? 2.41 ?g/ml). It is noteworthy to note that compound 6 was a selective inhibitor with the selectivity index of 11.82. Molecular insight from docking interaction further substantiate that orientation of compound 6 in the catalytic site which enhanced its binding affinity as compared to other xanthones. The nature of protein-ligand interactions of compound 6 is mainly hydrogen bonding, and the hydroxyl group of compound 6 at C-10 is vital in BChE inhibition activity. Therefore, compound 6 is a notable lead for further drug design and development of BChE selective inhibitor.

Phytochemicals from Goniothalamus griffithii Induce Human Cancer Cell Apoptosis

Banjerdpongchai, Ratana,Khaw-on, Patompong,Pompimon, Wialrt Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

Bioactive compounds extracted from leaves and twigs of Goniothalamus griffithii include pinocembrin (PCN) and goniothalamin (GTN). The objectives of this study were to investigate the cytotoxic activities of PCN and GTN and their influence on molecular signaling for cell death in several human cancer cell lines compared to normal murine fibroblast NIH3T3 cells. GTN exhibited the most potent cytotoxicity against MCF-7 > HeLa > HepG2 > NIH3T3 cells with $IC_{50}$ values of 7.33, 14.8, 37.1 and $65.4{\mu}M$, respectively, whereas PCN was cytotoxic only to HepG2 cells with $IC_{50}$ values of ${\sim}80{\mu}M$. Apoptotic cell death was confirmed by staining the cells with annexin V-FITC and propidium iodide (PI) employing flow cytometry. Apoptosis was shown by externalization of phosphatidylserine in goniothalamin-treated MCF-7 cells in a dose response manner. Positive PI-stained cells with the typical morphology of apoptotic cells were increased dose-dependently. Furthermore, reduction of mitochondrial transmembrane potential was found in goniothalamin-treated MCF-7, HepG2 and HeLa cells. GTN treatment in MCF-7 increased caspase-3, -8 and -9 activities while GTN-induced HeLa cells showed an increase of both caspase-3 and -9 activities. But an increased caspase-8 activity was demonstrated in GTN- and PCN-treated MCF-7 and HepG2 cells, respectively. Taken together, GTN- and PCN-induced human cancer cell apoptosis was through different molecular mechanisms or signaling pathways, which might be due to different machineries in different types of cancer cells, as evidenced by the compound-modulated caspase activities in both intrinsic and/or extrinsic pathways.

6,8-Dihydroxy-7-methoxy-1-methyl-azafluorenone Induces Caspase-8- and -9-mediated Apoptosis in Human Cancer Cells

Banjerdpongchai, Ratana,Khaw-on, Patompong,Ristee, Chantrarat,Pompimon, Wilart Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.4

6,8-Dihydroxy-7-methoxy-1-methyl-azafluorenone (DMMA), a purified compound from Polyalthia cerasoides roots, is cytotoxic to various cancer cell lines. The aims of this study were to demonstrate the type of cancer cell death and the mechanism(s) involved. DMMA inhibited cell growth and induced apoptotic death in human leukemic cells (HL-60, U937, MOLT-4), human breast cancer MDA-MB231 cells and human hepatocellular carcinoma HepG2 cells in a dose dependent manner, with $IC_{50}$ values ranging between 20-55 ${\mu}M$. DMMA also decreased cell viability of human peripheral blood mononuclear cells. The morphology of cancer cells induced by the compound after staining with propidium iodide and examined under a fluorescence microscope was condensed nuclei and apoptotic bodies. Mitochondrial transmembrane potential (MTP) was decreased after 24h exposure in all five types of cancer cells. DMMA-induced caspase-3, -8, and -9 activity was strongly induced in human leukemic HL-60 and MOLT-4 cells, while in U937-, MDA-MB231- and HepG2-treated cells there was partial induction of caspase. In conclusion, DMMA-induced activation of caspase-8 and -9 resulted in execution of apoptotic cell death in human leukemic HL-60 and MOLT-4 cell lines via extrinsic and intrinsic pathways.

Terpinen-4-ol Induces Autophagic and Apoptotic Cell Death in Human Leukemic HL-60 Cells

Banjerdpongchai, Ratana,Khaw-on, Patompong Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.12

Background: Terpinen-4-ol, a monoterpene, is found as the main component of essential oil extracts from many plants. In this study apoptotic and autophagic types of cell death induced by terpinen-4-ol and associated mechanisms were investigated in human leukemic HL-60 cells. Materials and Methods: The cytotoxicity of human leukemic U937 and HL-60 cells was determined by MTT assay. Cytochrome c release, expression of Bax, Bcl-2, Bcl-xl and cleaved Bid were determined by Western blotting. Cell morphology was examined under a transmission electron microscope. LC3-I/II, ATG5 and Beclin-1 levels were detected by immunoblotting. Results: Terpinen-4-ol exhibited cytotoxicity to human leukemic HL-60 but not U937 cells. The apoptotic response to terpinen-4-ol in HL-60 cells was due to induction of cytochrome c release from mitochondria and cleavage of Bid protein after the stimulation of caspase-8. There was a slightly decrease of Bcl-xl protein level. The characteristic cell morphology of autophagic cell death was demonstrated with multiple autophagosomes in the cytoplasm. At the molecular level, the results from Western blot analysis showed that terpinen-4-ol significantly induced accumulation of LC3-I/II, ATG5 and Beclin-1, regulatory proteins required for autophagy in mammalian cells. Conclusions: Terpinen-4-ol induced-human leukemic HL-60 cell death was via both autophagy and apoptosis.

Role of microRNAs as biomarkers of cervical carcinogenesis: a systematic review

( Kavitha Nagandla ),( Khaw Huang Lin ),( Ebenezer Chitra ),( Mohamed Faiz Bin Mohamed Jamli ) 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.5

We performed a systematic review to identify the role of microRNAs (miRNAs) as biomarkers in the progression of cervical precancerous lesions. A comprehensive search of the Cochrane Controlled Register of Trials, PubMed, ScienceDirect, and Embase databases was performed for articles published between January 2010 and June 2020. The following Medical Subject Headings (MeSH) terms were searched: “microRNA” and “cervical” and “lesion.” All study designs that aimed to evaluate the correlation of miRNA expression with different precancerous cervical staging and/ or cervical cancer were included, except for case reports and case series. Approximately 82 individual miRNAs were found to be significant in differentiating the stages of cervical carcinogenesis. Among the miRNAs, miR-21 is the most prevalent, and it is consistently upregulated progressively from normal cervical to worsening cervical lesion stages in both cell and serum samples. miR-205 has been shown to have a higher specificity than human papilloma virus testing in predicting the absence of high-grade squamous intraepithelial lesions (HSILs) in exfoliated cell samples. The tumor suppressor miRNAs miR-34, let-7, miR-203 miR-29, and miR-375 were significantly downregulated in lowgrade squamous intraepithelial lesions, HSILs, and cervical cancer. We found significant dysregulated miRNAs in cervical carcinogenesis with their dynamic expression changes and ability to detect viral persistency, risk prediction of low-grade lesions (cervical intraepithelial neoplasia [CIN] 2) to high-grade lesions (CIN 3), and progression of CIN 3 to cancer. Their ability to discriminate HSILs from non-dysplastic lesions has potential implications in early diagnosis and reducing overtreatment of otherwise regressive early preinvasive lesions.

New evidence of Lockup Provisions: Effects on IPO Demands

Mohd-Rashid, Rasidah,Khaw, Karren Lee-Hwei,Mehmood, Waqas,Tajuddin, Ahmad Hakimi World Association for Triple Helix and Future Stra 2022 Journal of Contemporary Eastern Asia Vol.21 No.1

This study examines the impacts of a mandatory lockup ratio and lockup period, together with voluntary lockup, on the initial public offering (IPO) subscription rate in Malaysia. A sample of 390 IPOs launched from 2000 to 2016 was collected for analysis. The findings show that firms that adopt a lower lockup ratio and a shorter lockup period signal uncertainty about their prospects. Issuers would then show the tendency to underprice to increase investors' intention to subscribe to firms' IPO shares. This study concludes that as long as investors are aware of pertinent information about IPO firms, they should continue participating in the IPO market rather than behaving irrationally. Finally, policymakers could use the findings to improve the existing lockup provisions regulation.

Induction of Human Hepatocellular Carcinoma HepG2 Cell Apoptosis by Naringin

Banjerdpongchai, Ratana,Wudtiwai, Benjawan,Khaw-on, Patompong Asian Pacific Journal of Cancer Prevention 2016 Asian Pacific journal of cancer prevention Vol.17 No.7

Naringin, a bioflavonoid found in Citrus seeds, inhibits proliferation of cancer cells. The objectives of this study were to investigate the mode and mechanism(s) of hepatocellular carcinoma HepG2 cell death induced by naringin. The cytotoxicity of naringin towards HepG2 cells proved dose-dependent, measured by MTT assay. Naringin-treated HepG2 cells underwent apoptosis also in a concentration related manner, determined by annexin V-fluorescein isothiocyanate (FITC) and propidium iodide (PI) employing flow cytometry. Mitochondrial transmembrane potential (MTP) measured using 3,3'-dihexyloxacarbocyanine iodide ($DiOC_6$) and flow cytometer was reduced concentration-dependently, which indicated influence on the mitochondrial signaling pathway. Caspase-3, -8 and -9 activities were enhanced as evidenced by colorimetric detection of para-nitroaniline tagged with a substrate for each caspase. Thus, the extrinsic and intrinsic pathways were linked in human naringin-treated HepG2 cell apoptosis. The expression levels of pro-apoptotic Bax and Bak proteins were increased whereas that of the anti-apoptotic Bcl-xL protein was decreased, confirming the involvement of the mitochondrial pathway by immunoblotting. There was an increased expression of truncated Bid (tBid), which indicated caspase-8 proteolysis activity in Bid cleavage as its substrate in the extrinsic pathway. In conclusion, naringin induces human hepatocellular carcinoma HepG2 cell apoptosis via mitochondria-mediated activation of caspase-9 and caspase-8-mediated proteolysis of Bid. Naringin anticancer activity warrants further investigation for application in medical treatment.

A 24-Year Follow-Up Study of Blood Pressure Tracking from Childhood to Adulthood in Korea: The Kangwha Study

이명하,서일,강대룡,김현창,안성복,Kay-Tee Khaw 연세대학교의과대학 2014 Yonsei medical journal Vol.55 No.2

Purpose: A number of longitudinal studies have tracked blood pressure over time in children and adults. Although there are a few blood pressure tracking studies for Asian populations, they are all relatively short-term studies with around only 10 years of follow-up. Accordingly, we assessed the stability of blood pressure tracking from childhood to adulthood over a 24-year follow-up period among participants in the Kangwha Study. Materials and Methods: The Kangwha Study was a community-based prospective cohort study that started in 1986 in Kangwha County, South Korea. The study dataset included 14 blood pressure measurements over a 24-year period from 266 (123 male and 143 female) participants who completed the 2010 examination. All participants were 7 years old when the study began and were followedfor the next 24 years. Results: The tracking coefficient (95% confidence interval)for systolic blood pressure was 0.81 (0.52-1.11) in men and 0.72 (0.51-0.92) in women; diastolic blood pressure was 0.53 (0.26-0.80) in men and 0.33 (0.15-0.52) in women. After adjusting for body mass index, the tracking coefficient for systolic blood pressure was 0.68 (0.39-0.97) in men and 0.67 (0.44-0.89) in women; diastolic blood pressure was 0.51 (0.24-0.78) in men and 0.33 (0.15-0.51) in women. All tracking coefficients were statistically significant (p<0.001). Conclusion: In this 24-year longitudinal study, we confirmed the stability of blood pressure tracking from childhood to adulthood for participants in the Kangwha Study.