• Title/Summary/Keyword: tumor growth

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LKB1/STK11 Tumor Suppressor Reduces Angiogenesis by Directly Interacting with VEGFR2 in Tumorigenesis

  • Seung Bae Rho;Hyun Jung Byun;Boh-Ram Kim;Chang Hoon Lee
    • Biomolecules & Therapeutics
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    • v.31 no.4
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    • pp.456-465
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    • 2023
  • Cervical tumors represent a prevalent form of cancer affecting women worldwide; current treatment options involve surgery, radiotherapy, and chemotherapy. Angiogenesis, the process of new blood vessel formation, is a crucial factor in cervical tumor growth. The molecular mechanisms underlying the effects of the liver kinase B1 (LKB1/STK11) tumor suppressor protein on tumor angiogenesis have not been elucidated. Therefore, we investigated the role of LKB1 in cervical tumor angiogenesis both in vitro and in vivo in this study. Our results demonstrated that LKB1 inhibited cervical tumor angiogenesis by suppressing the expression of angiogenesis-related factors such as vascular endothelial growth factor (VEGF) and hypoxia inducible factor-1α. LKB1 directly affected both carcinoma and vascular endothelial cells, resulting in a significant reduction in tumor growth and angiogenesis. Furthermore, LKB1 was found to bind to VEGF receptor 2 (VEGFR-2) and target the VEGFR-2-mediated protein kinase B/mechanistic target of rapamycin signaling pathway in endothelial cells, thereby reducing cervical tumor growth and angiogenesis. Our study provides new insights into the molecular mechanisms underlying the anti-tumor and anti-angiogenic effects of LKB1 in cervical cancer. These findings will help develop new therapeutic strategies for cervical cancer.

Licochalcone A, a Major Phenolic Constituent of Glycyrrhiza inflata, Suppresses Angiogenin Expression in Colon Cancer Cells

  • Kim, Jin-Kyung
    • Biomedical Science Letters
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    • v.17 no.1
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    • pp.85-88
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    • 2011
  • Tumor angiogenesis, which is essential for tumor growth and tumor metastasis, depends on angiogenic factors produced by tumor cells and/or infiltrating cells such as endothelial cells and immune cells in tumor tissue. Previously, we reported that licochalcone A (LicA), an important bioactive compound of Glycyrrhiza inflate, suppresses angiogenesis, tumor growth and metastasis. In this study, we evaluated the effect of LicA on angiogenin production in colon cancer cells because angiogenin is an essential factor to regulate angiogenesis and tumor progression. When we examined the angiogenin levels in three human colon cancer cells, HT-29, SW480 and Caco-2, LicA treatment significantly reduced the amounts of angiogenin among three cancer cell lines. In an in vivo study in which mice were implanted with HT-29 cells, oral administration of LicA reduced angiogenin in tumor tissues when compared with vehicle-administered mice. These results suggest that reduced angiogenin in response to LicA treatment may play essential role to inhibit tumor growth, angiogenesis as well as metastasis.

Vascular Morphometric Changes During Tumor Growth and Chemotherapy in a Murine Mammary Tumor Model Using OCT Angiography: a Preliminary Study

  • Kim, Hoonsup;Eom, Tae Joong;Kim, Jae Gwan
    • Current Optics and Photonics
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    • v.3 no.1
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    • pp.54-65
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    • 2019
  • To develop a biomarker predicting tumor treatment efficacy is helpful to reduce time, medical expenditure, and efforts in oncology therapy. In clinics, microvessel density using immunohistochemistry has been proposed as an indicator that correlates with both tumor size and metastasis of cancer. In the preclinical study, we hypothesized that vascular morphometrics using optical coherence tomography angiography (OCTA) could be potential indicators to estimate the treatment efficacy of breast cancer. To verify this hypothesis, a 13762-MAT-B-III rat breast tumor was grown in a dorsal skinfold window chamber which was applied to a nude mouse, and the change in vascular morphology was longitudinally monitored during tumor growth and metronomic cyclophosphamide treatment. Based on the daily OCTA maximum intensity projection map, multiple vessel parameters (vessel skeleton density, vessel diameter index, fractal dimension, and lacunarity) were compared with the tumor size in no tumor, treated tumor, and untreated tumor cases. Although each case has only one animal, we found that the vessel skeleton density (VSD), vessel diameter index and fractal dimension (FD) tended to be positively correlated with tumor size while lacunarity showed a partially negative correlation. Moreover, we observed that the changes in the VSD and FD are prior to the morphological change of the tumor. This feasibility study would be helpful in evaluating the tumor vascular response to treatment in preclinical settings.

Growth Pattern and Prognostic Factors of Untreated Nonfunctioning Pituitary Adenomas

  • Hwang, Kihwan;Kwon, Taehun;Park, Jay;Joo, Jin-Deok;Han, Jung Ho;Oh, Chang Wan;Kim, Chae-Yong
    • Journal of Korean Neurosurgical Society
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    • v.62 no.2
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    • pp.256-262
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    • 2019
  • Objective : Pituitary adenomas (PAs) are often detected as incidental findings. However, the natural history remains unclear. The objective of this study was to evaluate the natural history and growth pattern of untreated PAs. Methods : Between 2003 and 2014, 59 PAs were managed with clinico-radiological follow up for longer than 12 months without any kind of therapeutic intervention. Tumor volumes were calculated at initial and last follow-up visit, and tumor growth during the observation period was determined. Data were analyzed according to clinical and imaging characteristics. Results : The mean initial and last tumor volume and diameter were $1.83{\pm}2.97mL$ and $13.77{\pm}6.45mm$, $2.85{\pm}4.47mL$ and $15.75{\pm}8.08mm$, respectively. The mean annual tumor growth rate was $0.33{\pm}0.68mL/year$ during a mean observation period of $46.8{\pm}32.1months$. Sixteen (27%) PAs showed tumor growth. The initial tumor size (HR, 1.140; 95% confidence interval, 1.003-1.295; p=0.045) was the independent predictive factor that determined the tumor growth. Six patients (11%) of 56 conservatively managed non-symptomatic PAs underwent resection for aggravating visual symptoms with mean interval of 34.5 months from diagnosis. By Cox regression analysis, PAs of last longest diameter over 21.75 mm were a significant prognostic factor for eventual treatment. Conclusion : The initial tumor size of PAs was independently associated with the tumor growth. Six patients (11%) of conservatively managed PAs were likely to be treated eventually. PAs of last follow-up longest diameter over 21.75 mm were a significant prognostic factor for treatment. Further studies with a large series are required to determine treatment strategy.

A FRACTIONAL-ORDER TUMOR GROWTH INHIBITION MODEL IN PKPD

  • Byun, Jong Hyuk;Jung, Il Hyo
    • East Asian mathematical journal
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    • v.36 no.1
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    • pp.81-90
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    • 2020
  • Many compartment models assume a kinetically homogeneous amount of materials that have well-stirred compartments. However, based on observations from such processes, they have been heuristically fitted by exponential or gamma distributions even though biological media are inhomogeneous in real environments. Fractional differential equations using a specific kernel in Pharmacokinetic/Pharmacodynamic (PKPD) model are recently introduced to account for abnormal drug disposition. We discuss a tumor growth inhibition (TGI) model using fractional-order derivative from it. This represents a tumor growth delay by cytotoxic agents and additionally show variations in the equilibrium points by the change of fractional order. The result indicates that the equilibrium depends on the tumor size as well as a change of the fractional order. We find that the smaller the fractional order, the smaller the equilibrium value. However, a difference of them is the number of concavities and this indicates that TGI over time profile for fitting or prediction should be determined properly either fractional order or tumor sizes according to the number of concavities shown in experimental data.

Endostar Combined with Cisplatin Inhibits Tumor Growth and Lymphatic Metastasis of Lewis Lung Carcinoma Xenografts in Mice

  • Dong, Xiao-Peng;Xiao, Tian-Hui;Dong, Hong;Jiang, Ning;Zhao, Xiao-Gang
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.5
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    • pp.3079-3083
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    • 2013
  • Objective: To investigate the effects of endostar, a recombined humanized endostatin, plus cisplatin on the growth, lymphangiogenesis and lymphatic metastasis of the Lewis lung carcinoma (LLC) in mice. Methods: A tumor model were established in C57BL/6 mice by intravenious transplantation of LLC cells. Then the mice were randomized to receive administration with NS, endostar, cisplatin, or endostar plus cisplatin. After the mice were sacrificed, tumor multiplicity, tumor size and lymph node metastasis were assessed. Then the expression of vascular endothelial growth factor-c (VEGF-C) and podoplanin were determined by immunohistochemical staining. Results: Endostar plus cisplatin significantly suppressed tumor growth. lymphatic metastasis and prolonged survival time of the mice without obvious toxicity. The inhibition of lymphatic metastasis was associated with decreased microlymphatic vessel density (MLVD) and expression of VEGF-C. Conclusions: Endostar combined with cisplatin was more effective to suppress tumor growth and lymphatic metastasis than either agent alone. Thus this may provide a rational alternative for lung carcinoma treatment.

Development of Genetically Modified Tumor Cell Containing Co-stimulatory Molecule

  • Kim, Hong Sung
    • Biomedical Science Letters
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    • v.25 no.4
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    • pp.398-406
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    • 2019
  • Cancer immunotherapy using gene-modified tumor cells is safe and customized cancer treatment method. In this study, we made gene-modified tumor cells by transferring costimulatory molecules, 4-1BBL and OX40L, into tumor cells using lentivirus vector, and identified anti-cancer effect of gene-modified tumor cells in CT26 mouse colorectal tumor model. We construct pLVX-puro-4-1BBL, -OX40L vector for lentivirus production and optimized the transfection efficiency and transduction efficiency. The transfection efficiency is maximal at DNA:cationic polymer = 1:0.5 and DNA 2 ㎍ for lentivirus production. Then, the lentiviral including 4-1BBL and OX40L was used to deliver CT26 mouse tumor cells to establish optimal delivery conditions according to the amount of virus. The transduction efficiency is maximal at 500 μL volume of lentiviral stock without change in cell shape or growth rate. CT26-4-1BBL, CT26-OX40L significantly inhibited the tumor growth compare with CT26-WT or CT26-β-gal cell line. These data showed the possibility the use of genetically modified tumor cells with costimulatory molecule as cancer immunotherapy agent.

Scopolamine Production in Suspension Cultures of Tumor Calli from Datura metel L. (흰독말풀(Datura metel L.)종양 캘러스의 현탁배양으로부터 Scopolamine 생성)

  • 이수경;윤길영;김용해;양덕조
    • Korean Journal of Plant Tissue Culture
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    • v.27 no.3
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    • pp.203-211
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    • 2000
  • In this study to produce large-scale scopolamine we were examined in the tumor calli of Datura metel L. induced by Agrobacterium tumefaciens $Ery{101}$. The growth and scopolamine contents of tumor calli were higher under light condition than in dark. The optimum condition of growth and scopolamine production were fluence rate of 16 $\mu$mol $m^{-2}s^{-1}$, spectra of red light region and 16 hour light periods on 50 mL SH liquid medium in 4 weeks culture. To increase of the scopolamine contents in tumor calli, the optimum concentration of nitrogen source were 1.8 mM NH$_4$+ and 40 mM NO$_3$. The optimum elicitor concentration for production of scopolamine were 10 mg/L chitosan and 15 mg/L yeast extract. The effect of precursors were good at the concentration of 0.2 mM tropine and 0.3 mM tropic acid, respectively. In order to increase of growth and scopolamine contents. we induced mutant from Datura metel L. tumor callus. Mutants of tumor calli were obtained by 3 Krad, 4 Krad and 6 Krad of ${60}^Cor-ray$. Among them, 3 Krad tumor callus was excellent on the growth and teratoma induction. The 4 Krad tumor callus was negligible for both growth and teratoma induction. But the 6 Krad tumor callus was the best in growth and teratoma induction. The formation of the mutant calli can be enhanced through hormonal combination of 1 mg/L 2,4-dichlorophenoxyacetic acid and 0.5 mg/L benzyladenine. We carry out selection mutant tumor calli for high content tropane alkaloid and suspension cultures for scopolamine production.

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COX-2 increase tumor-associated angiogenesis and tumor growth by eNOS-dependent pathway (eNOS 의존적 pathway를 통한 COX-2의 tumor 성장 증가와 tumor 혈관신생 증가)

  • Sohn, Eun-Hwa;Nam, Seung-Koong
    • Proceedings of the KAIS Fall Conference
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    • 2011.05b
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    • pp.1068-1071
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    • 2011
  • Cyclooxygenases (COX)-2 has been highly expressed in a variety of tumor cells and involved inflammatory process, tumor-associated angiogenesis, and vascular functions but the underlying mechanism is not clearly elucidated. We here investigated the molecular mechanism by which COX-2 regulates tumor-associated angiogenesis. In vivo, we injected B16-F1 cells overexpressed with COX-2 or mock in wild type or eNOS-deficient mice. Tumor cells overexpressed with COX-2 increase tumor-associated angiogenesis and tumor growth compared with control cells and that the effect of COX-2 was lower in eNOS-deficient mice than wild type mice. These results may contribute to further understanding of the regulation of angiogenesis by COX during tumor metastasis and inflammation.

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Growth of Human Colon Cancer Cells in Nude Mice is Delayed by Ketogenic Diet With or Without Omega-3 Fatty Acids and Medium-chain Triglycerides

  • Hao, Guang-Wei;Chen, Yu-Sheng;He, De-Ming;Wang, Hai-Yu;Wu, Guo-Hao;Zhang, Bo
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.5
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    • pp.2061-2068
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    • 2015
  • Background: Tumors are largely unable to metabolize ketone bodies for energy due to various deficiencies in one or both of the key mitochondrial enzymes, which may provide a rationale for therapeutic strategies that inhibit tumor growth by administration of a ketogenic diet with average protein but low in carbohydrates and high in fat. Materials and Methods: Thirty-six male BALB/C nude mice were injected subcutaneously with tumor cells of the colon cancer cell line HCT116. The animals were then randomly split into three feeding groups and fed either a ketogenic diet rich in omega-3 fatty acids and MCT (MKD group; n=12) or lard only (LKD group; n=12) or a standard diet (SD group; n=12) ad libitum. Experiments were ended upon attainment of the target tumor volume of $600mm^3$ to $700mm^3$. The three diets were compared for tumor growth and survival time (interval between tumor cell injection and attainment of target tumor volume). Results: The tumor growth in the MKD and LKD groups was significantly delayed compared to that in the SD group. Conclusions: Application of an unrestricted ketogenic diet delayed tumor growth in a mouse xenograft model. Further studies are needed to address the mechanism of this diet intervention and the impact on other tumor-relevant parameters such as invasion and metastasis.