• Radiation Oncology Journal
• /
• v.22 no.2
• /
• pp.77-90
• /
• 2004

Purpose: The purpose of this review Is to provide an update on novel radiation treatments for head and neck cancer Recent Findings: Despite the remarkable advances In chemotherapy and radiotherapy techniques, the management of advanced head and neck cancer remains challenging. Epidermal growth factor receptor (EGFR) Is an appealing target for novel therapies In head and neck cancer because not only EGFR activation stimulates many important signaling pathways associated with cancer development and progression, and importantly, resistance to radiation. Furthermore, EGFR overexpression Is known to be portended for a worse outcome in patients with advanced head and neck cancer. Two categories of compounds designed to abrogate EGFR signaling, such as monoclonal antibodies (Cetuxlmab) and tyrosine kinase inhibitors (ZD1839 and 051-774) have been assessed and have been most extensively studied In preclinical models and clinical trials. Additional TKIs In clinical trials include a reversible agent, Cl-1033, which blocks activation of all erbB receptors. Encouraging preclinical data for head and neck cancers resulted In rapid translation Into the clinic. Results from Initial clinical trials show rather surprisingly that only minority of patients benefited from EGFR inhibition as monotherapy or In combination with chemotherapy. In this review, we begin with a brief summary of erbB- mediated signal transduction. Subsequently, we present data on prognostic-predictive value of erbB receptor expression in HNC followed by preclinlcal and clinical data on the role of EGFR antagonists alone or in combination with radiation In the treatment of HNC. Finally, we discuss the emerging thoughts on resistance to EGFR biockade and efforts In the development of multiple-targeted therapy for combination with chemotherapy or radiation. Current challenges for investigators are to determine (1 ) who will benefit from targeted agents and which agents are most appropriate to combine with radiation and/or chemotherapy, (2) how to sequence these agents with radiation and/or cytotoxlc compounds, (3) reliable markers for patient selection and verification of effective blockade of signaling in vivo, and (4) mechanisms behind intrinsic or acquired resistance to targeted agents to facilitate rational development of multi-targeted therapy, Other molecuiar-targeted approaches In head and neck cancer were briefly described, Including angloenesis Inhibitors, farnesyl transferase inhibitors, cell cycle regulators, and gene therapy Summary: Novel targeted theraples are highly appealing in advanced head and neck cancer, and the most premising strategy to use them Is a matter of intense Investigation.

• Molecules and Cells
• /
• v.41 no.3
• /
• pp.244-255
• /
• 2018

Low-grade pro-inflammatory state and leptin resistance are important underlying mechanisms that contribute to obesity-associated hypertension. We tested the hypothesis that Astragaloside IV (As IV), known to counteract obesity and hypertension, could prevent obesity-associated hypertension by inhibiting pro-inflammatory reaction and leptin resistance. High-fat diet (HFD) induced obese rats were randomly assigned to three groups: the HFD control group (HF con group), As IV group, and the As IV + ${\alpha}$-bungaratoxin (${\alpha}-BGT$) group (As IV+${\alpha}-BGT$ group). As IV ($20mg{\cdot}Kg^{-1}{\cdot}d^{-1}$) was administrated to rats for 6 weeks via daily oral gavage. Body weight and blood pressure were continuously measured, and NE levels in the plasma and renal cortex was evaluated to reflect the sympathetic activity. The expressions of leptin receptor (LepRb) mRNA, phosphorylated signal transducer and activator of transcription-3 (p-STAT3), phosphorylated phosphatidylinositol 3-kinase (p-PI3K), suppressor of cytokine signaling 3 (SOCS3) mRNA, and protein-tyrosine phosphatase 1B (PTP1B) mRNA, pro-opiomelanocortin (POMC) mRNA and neuropeptide Y (NPY) mRNA were measured by Western blot or qRT-PCR to evaluate the hypothalamic leptin sensitivity. Additionally, we measured the protein or mRNA levels of ${\alpha}7nAChR$, inhibitor of nuclear factor ${\kappa}B$ kinase subunit ${\beta}/nuclear$ factor ${\kappa}B$ ($IKK{\beta}/NF-KB$) and pro-inflammatory cytokines ($IL-1{\beta}$ and $TNF-{\alpha}$) in hypothalamus and adipose tissue to reflect the anti-inflammatory effects of As IV through upregulating expression of ${\alpha}7nAChR$. We found that As IV prevented body weight gain and adipose accumulation, and also improved metabolic disorders in HFD rats. Furthermore, As IV decreased BP and HR, as well as NE levels in blood and renal tissue. In the hypothalamus, As IV alleviated leptin resistance as evidenced by the increased p-STAT3, LepRb mRNA and POMC mRNA, and decreased p-PI3K, SOCS3 mRNA, and PTP1B mRNA. The effects of As IV on leptin sensitivity were related in part to the up-regulated ${\alpha}7nAchR$ and suppressed $IKK{\beta}/NF-KB$ signaling and pro-inflammatory cytokines in the hypothalamus and adipose tissue, since co-administration of ${\alpha}7nAChR$ selective antagonist ${\alpha}-BGT$ could weaken the improved effect of As IV on central leptin resistance. Our study suggested that As IV could efficiently prevent obesityassociated hypertension through inhibiting inflammatory reaction and improving leptin resistance; furthermore, these effects of As IV was partly related to the increased ${\alpha}7nAchR$ expression.

• Journal of Dental Rehabilitation and Applied Science
• /
• v.25 no.3
• /
• pp.293-306
• /
• 2009

In this study, the biological response of fetal rat calvarial cells on alkali- and heat-treated titanium was assessed. The results were as follows; Cell proliferation on alkali- and heat-treated surfaces showed significantly higher level than on the titanium-6aluminum-4vanadium (weight percentage: 6 % aluminum, 4 % vanadium, Ti-6Al-4V) surface (p<0.01). In ELISA analysis, concentration of $IL-1{\beta}$ and IL-6 were raised when the cells were grown to day 7. Pre-treatment with herbimycin, a known tyrosine kinase inhibitor, suppressed the production of IL-6 (p<0.01). In comparison to commercially pure titanium (grade II, cp-Ti) and Ti-6Al-4V alloy, alkali- and heat-treated titanium enhanced alkaline phosphatase activity (p<0.001). In RT-PCR analysis, alkaline phosphatase, bone sialoprotein, receptor activated nuclear factor ligand mRNA expression was increased alkali- and heat-treated titanium. Herbimycin and SB203580, p38 MAPK inhibitor, were repressed of $IL-1{\beta}-induced$ IL-6 mRNA expression. These results suggest that alkali- and heat-treated titanium stimulate osteoblasts differentiation and facilitate bone remodeling.

• Archives of Pharmacal Research
• /
• v.29 no.3
• /
• pp.224-234
• /
• 2006

We employed human SK-MEL-28 cells as a model system to identify cellular proteins that accompany N-(4-methyl)phenyl-O-(4-methoxy)phenyl-thionocarbamate (MMTC)-induced apoptosis based on a proteomic approach. Cell viability tests revealed that SK-MEL-28 skin cancer cells underwent more cell death than normal HaCaT cells in a dose-dependent manner after treatment with MMTC. Two-dimensional electrophoresis in conjunction with matrixassisted laser desorption/ionization-time of flight (MALDI-TOF) mass spectrometry analysis or computer matching with a protein database further revealed that the MMTC-induced apoptosis is accompanied by increased levels of caspase-1, checkpoint suppressor-1, caspase-4, NF-kB inhibitor, AP-2, c-Jun-N-terminal kinase, melanoma inhibitor, granzyme K, G1/S specific cyclin D3, cystein rich protein, Ras-related protein Rab-37 or Ras-related protein Rab-13, and reduced levels of EMS (oncogene), ATP synthase, tyrosine-phosphatase, Cdc25c, 14-3-3 protein or specific structure of nuclear receptor. The migration suppressing effect of MMTC on SK-MEL-28 cell was tested. MMTC suppressed the metastasis of SK-MEL-8 cells. It was also identified that MMTC had little angiogenic effect because it did not suppress the proliferation of HUVEC cell line. These results suggest that MMTC is a novel chemotherapeutic and metastatic agents against the SK-MEL-28 human melanoma cell line.

• Journal of Life Science
• /
• v.19 no.12
• /
• pp.1690-1697
• /
• 2009

CD11c and costimulatory molecules such as CD80 and CD86 express mainly in dendritic cells (DCs). In this study, we investigated the biologic effects of recombinant Fms-like tyrosine kinase-3 (Flt-3) ligand on the expression of DC surface markers, including CD11c in leukemia cell lines, such as KG-1, HL-60, NB4, and THP-1 cells. The expression of the Flt-3 receptor was found in NB4 and HL-60 cells, as well as KG-1 cells, but not in THP-1 cells. When KG-1 cells were cultured in a medium containing Flt-3 ligand or granulocyte macrophage-colony stimulating factor (GM-CSF) plus tumor necrosis factor (TNF)-$\alpha$, cell proliferation was inhibited and the expression levels of CD11c, major histocompatibility complex (MHC)-I, and MHC-II were increased in the cells. Flt-3 ligand also increased the expression level of CD11c on HL-60 and NB4 cells, but not on THP-1 cells. In comparison with CD11c expression, the expression level of CD11b on KG-1 cells, but not on NB4 and HL-60 cells, was slightly increased by Flt-3 ligand. Flt-3 ligand induced phosphorylation of extracellular signal-regulated kinase-1/2 (ERK-1/2) and p38-mitogen-activated protein kinase (p38-MAPK) in KG-1 cells, and the up-regulation of CD11c expression by Flt-3 ligand in the cells was abrogated by PD98059, an inhibitor of MEK. The results suggest that Flt-3 ligand up-regulates DC surface markers on $CD34^+$ myelomonocytic KG-1 cells, as well as promyelocytic leukemia cells, and that the differentiation of the leukemia cells into DC-like cells by Flt-3 ligand is mediated by ERK-1/2 activity.

• Tuberculosis and Respiratory Diseases
• /
• v.47 no.5
• /
• pp.618-628
• /
• 1999

Background: Cell growth is a balance between cell proliferation and cell death. Insulin-like growth factor-I(IGF-I), which binds IGF-I receptor(IGF-IR), mediates cellular proliferation as a potent mitogen. IGF binding protein-3(IGFBP-3) as a circulating major IGFBP can inhibit or enhance the effects of IGF-I on cellular growth by binding IGFs. Methods: We investigated the expressions of mRNA of IGF-I and IGF-IR by northern blot and phosphorylation of IGF-IR with the treatment of IGF-I by western blot in 3T3 fibroblast cells. The cellular proliferations of 3T3 cells with the treatments of IGF-I were evaluated using $^3H$-thymidine incorporation and MTT assay. Also to observe the effect of IGFBP-3 on cellular proliferation, 3T3 cells were treated with anti-IGFBP-3 and ${\alpha}IR_3$(monoclonal antibody to IGF-IR) alone or in combination. Results: Our results demonstrated that 3T3 cells showed mRNA expressions of IGF-I and IGF-IR and the IGF-I increased phosphorylation of IGF-IR. The treatments of 3T3 cells with IGF-I increased cellular proliferation in 5 % and 1 % seruma-containing media, not in serum-free media. The addition of anti-IGFBP-3 to neutralize IGFBP-3 showed 2-fold increase of cellular proliferation, and also co-incubation of anti-IGFBP-3 and ${\alpha}IR_3$ together showed similar increase of cellular proliferation in 3T3 cells. Interestingly, when the cells were pretreated with ${\alpha}IR_3$ for 4 hr, prior to the simultaneous addition of ${\alpha}IR_3$ and anti-IGFBP-3, anti-IGFBP-3-mediated cellular proliferation was decreased to control level. All of these results suggest that free IGF-I released from IGF-I/IGFBP-3 complex would be involved in the cellular proliferation. Conclusion: IGF-I is a mitogen through the activation of IGF-IR in 3T3 cells, and IGFBP-3 could be a potent inhibitor for IGF-I action by binding IGF-I.

• Tuberculosis and Respiratory Diseases
• /
• v.55 no.1
• /
• pp.21-30
• /
• 2003

Background : Mucin synthesis in airways has been reported to be regulated by the epidermal growth factor receptor (EGFR) system. Epidermal growth factor receptor transactivation was identified as a critical element in G-protein-coupled receptors (GPCRs)-induced mitogenic signaling. EGF receptor transactivation by G-protein-coupled receptors requires metalloproteinase cleavage of proHB-EGF. This study was hypothesized that lipopolysaccharide (LPS)-induced mucin production associates with epidermal growth factor receptor transactivation, and MUC5AC production associates with epidermal growth factor receptor transactivation by G-protein-coupled receptors that regulates by metalloproteinase. Method : MUC5AC mucin production was examined in NCI-H292 cells and MUC5AC protein synthesis was assessed using ELISA. For the evaluation of mechanism of LPS-induced MUC5AC production, $TNF{\alpha}$ was measured using ELISA with or without pretreatment of heterotrimeric G-protein inhibitor, mastoparan. MUC5AC protein was measure with pretreatment of polyclonal $TNF{\alpha}$ antibody or mastoparan on LPS-induced MUC5AC production. For the evaluation of relation of G-protein and MUC5AC production, G-protein stimulant, mastopara-7, or matrix metalloproteinase, ADAM10, was added to NCI-H292 cells. MUC5AC protein was measure with pretreatment of polyclonal EGF antibody on mastoparan-7-induced MUC5AC production. Results : LPS alone did not increase significantly MUC5AC production. LPS with $TNF{\alpha}$ induced dose-dependently MUC5AC production in NCI-H292 cells. LPS increased dose-dependently $TNF{\alpha}$ secretion, which was inhibited by mastoparan. LPS with $TNF{\alpha}$-induced MUC5AC production was inhibited by neutralizing polyclonal $TNF{\alpha}$ antibody, mastoparan or AG 1472. Mastoparan-7 or ADAM10 increased dose-dependently MUC5AC production, which was inhibited by polyclonal neutralizing EGF antibody. Conclusion : In LPS-induced MUC5AC synthesis, LPS causes $TNF{\alpha}$ secretion, which induces EGFR expression. EGFR tyrosine kinase phosphorylation result in MUC5AC production. EGF-R transactivation by G-protein-coupled receptors requires matrix metalloproteinase cleavage of proHB-EGF.

• Laboratory Medicine Online
• /
• v.7 no.1
• /
• pp.13-19
• /
• 2017

Background: We evaluated a sensitive and quantitative method utilizing fragment analysis of the fms-like tyrosine kinase 3-internal tandem duplication (FLT3-ITD), simultaneously measuring mutant allele burden and length, and verified the analytical performance. Methods: The number and allelic burden of FLT3-ITD mutations was determined by fragment analysis. Serial mixtures of mutant and wild-type plasmid DNA were used to calculate the limit of detection of fragment analysis, conventional PCR, and Sanger sequencing. Specificity was evaluated using DNA samples derived from 50 normal donors. Results of fragment analysis were compared to those of conventional PCR, using 481 AML specimens. Results: Defined mixtures were consistently and accurately identified by fragment analysis at a 5% relative concentration of mutant to wild-type, and at 10% and 20% ratios by conventional PCR and direct sequencing, respectively. No false positivity was identified. Among 481 AML specimens, 40.1% (193/481) had FLT3-ITD mutations. The mutant allele burden (1.7-94.1%; median, 28.2%) and repeated length of the mutation (14-153 bp; median, 49 bp) were variable. The concordance rate between fragment analysis and conventional PCR was 97.7% (470/481). Fragment analysis was more sensitive than conventional PCR and detected 11 additional cases: seven had mutations below 10%, three cases represented conventional PCR failure, and one case showed false negativity because of short ITD length (14 bp). Conclusions: The new fragment analysis method proved to be sensitive and reliable for the detection and monitoring of FLT3-ITD in patients with AML. This could be used to simultaneously assess ITD mutant allele burden and length.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.11
• /
• pp.4555-4561
• /
• 2014

Background: Silencing due to methylation of suppressor of cytokine signaling-3 (SOCS-3), a negative regulator gene for the JAK/STAT signaling pathway has been reported to play important roles in leukemogenesis. Imatinib mesylate is a tyrosine kinase inhibitor that specifically targets the BCR-ABL protein and induces hematological remission in patients with chronic myeloid leukemia (CML). Unfortunately, the majority of CML patients treated with imatinib develop resistance under prolonged therapy. We here investigated the methylation profile of SOCS-3 gene and its downstream effects in a BCR-ABL positive CML cells resistant to imatinib. Materials and Methods: BCR-ABL positive CML cells resistant to imatinib (K562-R) were developed by overexposure of K562 cell lines to the drug. Cytotoxicity was determined by MTS assays and $IC_{50}$ values calculated. Apoptosis assays were performed using annexin V-FITC binding assays and analyzed by flow cytometry. Methylation profiles were investigated using methylation specific PCR and sequencing analysis of SOCS-1 and SOCS-3 genes. Gene expression was assessed by quantitative real-time PCR, and protein expression and phosphorylation of STAT1, 2 and 3 were examined by Western blotting. Results: The $IC_{50}$ for imatinib on K562 was 362nM compared to 3,952nM for K562-R (p=0.001). Percentage of apoptotic cells in K562 increased upto 50% by increasing the concentration of imatinib, in contrast to only 20% in K562-R (p<0.001). A change from non-methylation of the SOCS-3 gene in K562 to complete methylation in K562-R was observed. Gene expression revealed down-regulation of both SOCS-1 and SOCS-3 genes in resistant cells. STAT3 was phosphorylated in K562-R but not K562. Conclusions: Development of cells resistant to imatinib is feasible by overexposure of the drug to the cells. Activation of STAT3 protein leads to uncontrolled cell proliferation in imatinib resistant BCR-ABL due to DNA methylation of the SOCS-3 gene. Thus SOCS-3 provides a suitable candidate for mechanisms underlying the development of imatinib resistant in CML patients.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.3
• /
• pp.2101-2105
• /
• 2013

Background: Long-term survival is a problem with locally advanced and metastatic renal cell carcinomas. Sunitinib malate is an oral multitargeted tyrosine kinase inhibitor, but data on sunitinib use as a second line treatment in metastatic renal cell carcinoma (mRCC) are limited. Prognostic and predictive value of peripheral blood markers has been shown for many cancers. Materials and Methods: Efficacy and safety profiles of sunitinib after interferon alpha (IFN-${\alpha}$) were evaluated based on retrospective data for 23 patients with mRCC. Hematological parameters (neutrophils, lymphocytes, platelets, mean platelet volume, neutrophil/lymphocyte ratio, platelet/lymphocyte ratio) were recorded at the time of metastasis. It was evaluated whether hematological parameters were prognostic and predictive factors. Results: Median progression-free survival (PFS) time was 16.5 months (95%CI: 0-34.5). Median overall survival (OS) time was 25.7 months (95%CI: 10.8-40.0). Most common side effects were neutropenia (52.2%), stomatitis (26.1%) and hand-food syndrome (26.1%). PFS was found 3.13 vs 17.1 months in patients with neutrophil / lymphocyte ratio (NLR)>3 vs $NLR{\leq}3$ (p:0.012). Median OS was 6.96 vs 27.1 months in patients with NLR>3 vs $NLR{\leq}3$ (p:0.001).While 75% of patients who responded to sunitinib had $NLR{\leq}3$, in 72% of patients with no response to sunitinib NLR>3 was detected (p:0.036). The association between the Memorial Sloan-Kettering Cancer Center (MSKCC) criteria and NLR was statistically significant (p:0.022). Conclusions: Data on second line sunitinib treatment following cytokine in mRCC are limited. In our study, we observed second line sunitinib treatment following IFN-${\alpha}$ to be effective and tolerable. NLRappeared to have prognostic and predictive value.