• Journal of Life Science
• /
• v.18 no.6
• /
• pp.884-890
• /
• 2008

Genistein, an isoflavone in soybean products, is a potential chemopreventive agent against various types of cancer. There are several studies documenting molecular alterations leading to cell cycle arrest at G2/M phase and induction of apoptosis; however, its mechanism of action and its molecular targets on the prostaglandin $E_2$ ($PGE_2$) production and telomere length regulation in human cancer remain unclear. In this study, we investigated the effect of genistein on the levels of cyclooxygenases (COXs) and telomere regulatory components of several human cancer cell lines (T24, human bladder carcinoma cells; U937, human leukemic cells; AGS, human stomach adenocarcinoma cells and SK-MEL-2, human skin melanoma cells). Genistein treatment resulted in the inhibition of cancer cell proliferation in a concentration-dependent manner. It was found that genistein treatment markedly decreased the levels of COX-2 mRNA and protein expression without significant changes in the expression of COX-1, which was correlated with a decrease in $PGE_2$ synthesis. Genistein treatment also partly inhibited the levels of human telomerase reverse transcriptase (hTERT) as well as human telomerase RNA (hTR) and telomerase-associated protein (TEP)-1, and the activity of telomerase. Taken together, these findings provide important new insights into the possible molecular mechanisms of the anti-cancer activity of genistein.

• Oncology Letters
• /
• v.42 no.5
• /
• pp.2149-2158
• /
• 2019

Primary refractory acute myeloid leukemia (AML) and early recurrence of leukemic cells are among the most difficult hurdles to overcome in the treatment of AML. Moreover, uncertainties surrounding the molecular mechanism underlying refractory AML pose a challenge when it comes to developing novel therapeutic drugs. However, accumulating evidence suggests a contribution of phosphatase and tensin homolog (PTEN)/protein kinase B (AKT) signaling to the development of refractory AML. To assess PTEN/AKT signaling in AML, two types of AML cell lines were evaluated, namely control HL60 cells and KG1α cells, a refractory AML cell line that is resistant to idarubicin and cytarabine (AraC) treatment. Changes in the expression level of glycolysis- and mitochondrial oxidative phosphorylation-related genes and proteins were evaluated by reverse transcription-quantitative polymerase chain reaction and western blot analyses, respectively. The mitochondrial oxygen consumption and extracellular acidification rates were measured using an XF24 analyzer. CCK8 assay and Annexin V/PI staining were used to analyze cell viability and cellular apoptosis, respectively. The PTEN protein was found to be depleted, whereas AKT phosphorylation levels were elevated in KG1α cells compared with HL60 cells. These changes were associated with increased expression of glucose transporter 1 and hexokinase 2, and increased lactate production. AKT inhibition decreased the proliferation of KG1α cells and decreased extracellular acidification without affecting HL60 cells. Notably, AKT inhibition increased the susceptibility of KG1α cells to chemotherapy with idarubicin and AraC. Taken together, the findings of the present study indicate that activation of AKT by PTEN deficiency sustains the refractory AML status through enhancement of glycolysis and mitochondrial respiration, effects that may be rescued by inhibiting AKT activity.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.35 no.6
• /
• pp.459-461
• /
• 2009

Polycythemia vera is one type of myeloproliferative disorder which occurs due to the clonal proliferation of hematopoietic stem cell related to the production of leukocyte and megakaryocyte which produces a little less than erythrocyte. Polycythemia vera has a peak incidence in the sixth decade of life with males affected slightly more frequently than females. Vasquez first described polycythemia vera as an autonomous erythrocytosis in 1892, and a further description, delineation of the disease process and a complete course outline were made in 1899, 1903 and 1938, respectively. Symptoms include pruritus, tinnitus, vertigo, gastrointestinal (GI) pain, and bleeding gums. Hyperuricemia and hyperuricosuria are present in about 40% of these patients. Complications are hemorrhage, thrombosis, post-polycythemic myeloid metaplasia, and leukemic transformation. In case of surgery, complications such as hemorrahge and thrombosis are highly likable to happen. We report a case of preoperative and postoperative of a 63-year-old male, who was diagnosed as oral cavity cancer in the mouth floor, with known history of hypertension and polycythemia vera. We considered that conservative management would be an advisable treatment for patients with uncontrolled systemic disease.

• The Korean Journal of Cytopathology
• /
• v.9 no.1
• /
• pp.21-28
• /
• 1998

Cytologic evaluation of cerebrospinal fluid(CSF) is an effective tool in diagnosing many disorders involving the central nervous system(CNS). CSF examination has been found to be of particular value in the diagnosis of metastatic carcinoma, lymphomatous or leukemic involvement of CNS and certain primary CNS tumors. As a survey of metastatic tumors to CSF and an evaluation of the preparation techniques increasing cellular yield in our laboratory, 713 CSF specimens examined between July 1995 and April 1997(1 year 10 months), were reviewed. There were 75 positive and 5 suspicious cases, the latter have had no evidence of tumors clinically. Primary tumors of 75 positive cases were classified as follows; 4(5.3%) as primary brain tumors, 40(53.3%) as secondary carcinomas, 13(17.3%) as leukemias, and 18 (24.0%) as lymphomas. The most common primary site of metastatic carcinomas was the lung in 17 cases(42.5%) followed by the stomach in 13(32.5%), breast in 8 (20.0%), and unknown primary in 2(5.0%). Four primary brain tumors were 3 cerebellar medulloblastomas and a supratentorial primitive neuroectodermal tumor (PNET). All 40 metastatic carcinomas were adenocarcinoma presented as single cells or cell clusters. Although signet ring cells were frequent in the cases of gastric primary cancers, no significant cytologic differences according to the primary site were observed. The cytologic features of leukemia and lymphoma were characterized by hypercellular smears presenting as individual atypical cells with increased N/C ratio, presence of nucleoli, and nuclear protrusions. In medulloblastomas and PNET, the principal cytologic findings were small undifferentiated cells arranged singly or in loose clusters with occasional rosettoid features. This study suggests that the CSF cytology is useful in the diagnosis of malignancy, especially metastatic extracranial tumors and the diagnostic accuracy can be improved by increasing cellular yield using cytocentrifuge.

• The Korean Journal of Physiology and Pharmacology
• /
• v.16 no.1
• /
• pp.31-36
• /
• 2012

The receptor activator of NF-${\kappa}B$ ligand (RANKL) signal is an activator of tumor necrosis factor receptor-associated factor 6 (TRAF6), which leads to the activation of NF-${\kappa}B$ and other signal transduction pathways essential for osteoclastogenesis, such as $Ca^{2+}$ signaling. However, the intracellular levels of inositol 1,4,5-trisphosphate ($IP_3$) and $IP_3$-mediated cellular function of RANKL during osteoclastogenesis are not known. In the present study, we determined the levels of $IP_3$ and evaluated $IP_3$-mediated osteoclast differentiation and osteoclast activity by RANKL treatment of mouse leukemic macrophage cells (RAW 264.7) and mouse bone marrow-derived monocyte/macrophage precursor cells (BMMs). During osteoclastogenesis, the expression levels of $Ca^{2+}$ signaling proteins such as $IP_3$ receptors ($IP_3Rs$), plasma membrane $Ca^{2+}$ ATPase, and sarco/endoplasmic reticulum $Ca^{2+}$ ATPase type2 did not change by RANKL treatment for up to 6 days in both cell types. At 24 h after RANKL treatment, a higher steady-state level of $IP_3$ was observed in RAW264.7 cells transfected with green fluorescent protein (GFP)-tagged pleckstrin homology (PH) domains of phospholipase C (PLC) ${\delta}$, a probe specifically detecting intracellular $IP_3$ levels. In BMMs, the inhibition of PLC with U73122 [a specific inhibitor of phospholipase C (PLC)[ and of $IP_3Rs$ with 2-aminoethoxydiphenyl borate (2APB; a non-specific inhibitor of $IP_3Rs$) inhibited the generation of RANKL-induced multinucleated cells and decreased the bone-resorption rate in dentin slice, respectively. These results suggest that intracellular $IP_3$ levels and the $IP_3$-mediated signaling pathway play an important role in RANKL-induced osteoclastogenesis.

• The Korean Journal of Physiology and Pharmacology
• /
• v.14 no.6
• /
• pp.407-412
• /
• 2010

3-Deazaadenosine (DZA), a potent inhibitor of S-adenosylhomocysteine hydrolase, was previously proposed to induce intrinsic apoptosis in human leukemic cells. In the present study, we analyzed the mechanism underlying the DZA-induced intrinsic apoptotic pathway. DZA activated typical caspase-dependent apoptosis in HL-60 cells, as demonstrated by an accumulation of hypo-diploidic cells, the processing of multiple procaspases and an inhibitory effect of z-VAD-Fmk on this cell death. During DZA-induced apoptosis, cytochrome c (cyt c) was released into the cytosol. This was neither prevented by z-VAD-Fmk and nor was it associated with the dissipation of mitochondrial membrane potential (${\Delta}{\Psi}_m$). Prior to the release of cyt c, BAX was translocated from the cytosol to mitochondria and underwent oligomerization. Finally, the overexpression of BCL-XL protected HL-60 cells from apoptosis by blocking both the cyt c release and BAX oligomerization. Collectively, these findings suggest that DZA may activate intrinsic apoptosis by stimulating BAX activation and thereby the release of cyt c.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.26 no.3
• /
• pp.310-312
• /
• 2000

Leukemia is a malignancy caused by precursor cells of white blood cell. It is a malignant tumor of hematopoietic organs, characterized by the disorder of hematopoietic function due to the proliferation of immature bone marrow cells or lymphatic cells and by abnormal tissue infiltration of leukemic cells. The major signs of leukemia are caused by the failure of bone marrow function. As the number of red blood cells decreases, anemia is to appear. The number of white blood cells in leukemia is usually increased but immature white blood cells circulating the body has little defense ability, thus become susceptible to infection. 27 year-old female patient who was treated chemotherapy and bone marrow transplantation after diagnosed as chronic myelogenous leukemia(CML) was diagnosed as osteomyelitis in mandible after clinical and dental radiographic film examination. Because of the result of examination, the involved tooth of the patient was extracted accompanied by sequestrectomy and saucerization under general anesthesia. After the patient had long term medication of antibiotics, the lesion was healed. Therefore. author, et al. report this case with literature review.

• Maxillofacial Plastic and Reconstructive Surgery
• /
• v.31 no.6
• /
• pp.535-540
• /
• 2009

Proliferation of abnormal hematopoietic cells with impaired differentiation, regulation and programmed cell death leads to leukemia. AML(acute myeloid leukemia) is a malignancy with malfunction of myeloid hematopoietic cells with acute behavior. The oral manifestations of the disease are posterior palate hemorrhage, gingival bleeding and gingival ulceration as a result of infection by normal oral flora and gingival infiltration by leukemic cells. A 49-year-old male patient was referred from local dental clinic. The patient was diagnosed with AML FAB M1 (acute myeloid leukemia French-American-British classification M1 myeloblastic leukemia without maturation). The oral infection focus was removed by a conservative treatment. 2 days after the dental treatment, the patient underwent chemotherapy. At 8-month follow-up, the overall outcome was excellent. Oral manifestations of AML are often the first indications of the malignancy. Therefore it is essential for dentists, especially oral and maxillofacial surgeons, to be aware of the diagnostic signs and complications associated with leukemia for better diagnosis and subsequent treatment and management.

• The Journal of Pediatrics of Korean Medicine
• /
• v.18 no.2
• /
• pp.31-48
• /
• 2004

Objective : KagamJwagwiEum(KJE) has been used for the purpose of prevention and treatment of bronchial asthma and allergic asthma in Korea. To investigate the biological effect of KJE, the author examined cytotoxicity and inflammatory cytokines secretion with human leukemic mast cell line, HMC-1. Methods: HMC-1 was stimulated with phorbol 12-myristate 13-acetate(PMA) and calcium ionophore A23187. KJE by itself had no effect on viability of HMC-l. The effects of KJE on the secretion of tumor necrosis $factor-alpha(TNF-{\alpha})$, interleukin(IL)-6 and IL-8 from HMC-1 were evaluated with enzyme-linked immunosorbent assay. Results : KJE inhibited PMA plus A23187-induced $TNF-{\alpha}$ and IL-6 secretion. But KJE had no effect IL-8 secretion: KJE had immunoregulatory effects on cytokines, increased secretion of NO and $TNF-{\alpha}$ but did not effect IL-12 secretion when the cells were primed and trigged with $IFN-{\gamma}$ in the peritoneal macrophages of C57BL/6 mice. Conclusions : Taken together, these results suggest that KJE inhibit the production of inflammatory cytokines in HMC-1 cells and activate macrophages.

• Advances in Traditional Medicine
• /
• v.7 no.4
• /
• pp.341-347
• /
• 2007

Red seaweed (Callophyllis japonica) has long formed part of the diet of Asians, but the pharmacological properties of this plant have not been evaluated. In this study, we examined the effect of an ethanol extract of C. japonica on the generation of nitric oxide (NO) in RAW 264.7 cells. The C. japonica extract increased the generation of NO and tumor necrosis $factor-{\alpha}$ ($TNF-{\alpha}$), which were detected by the Griess method and an enzyme-linked immunosorbent assay, respectively. The increased production of NO by C. japonica extract was inhibited by $N^G$-monomethyl-L-arginine ($100{\mu}M$), a specific inhibitor of NO production in the L-arginine-dependent pathway, and by the nuclear $factor-{\kappa}B$ ($NF-{\kappa}B$) inhibitor, pyrrolidine dithiocarbamate ($10-100{\mu}M$) in a dose-dependent manner. These findings demonstrate that C. japonica extract stimulates the production of NO and $TNF-{\alpha}$ in RAW 264.7 cells through the activation of $NF-{\kappa}B$ and that this extract might also inhibit the growth of the human leukemic cells.