• Title/Summary/Keyword: tumor initiation

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Induction of Ornithine Decarboxylase and Tumor Promotion by N-Methyl-N′-Nitro-N-Nitrosoguanidine, Sodium Chloride, and Dimethyl Itaconate

  • Aeree moon, Aeree-Moon;Kim, Dae-Joong;Han, Beom-Seok;Hwang, Moon-Ok;Kim, Chang-Ok;Choi, Kwang-Sik
    • Biomolecules & Therapeutics
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    • v.1 no.2
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    • pp.137-142
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    • 1993
  • The possible tumor-promoting activities of sodium chloride (NaCl) and dimethyl itaconate (DMI), one of the quinone reductase inducers, were examined on stomach of male Wistar rats treated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Administrations of NaCl and DMI after the initiation by MNNG resulted in various sized masses in the rat forestomach. Histopathologic studies showed that the combination of NaCl and DMI made an enhancing effect on the MNNG-induced carcinogenesis, resulting in papilloma in 5 weeks and squamous cell carcinoma in 20 weeks in submucosal area of forestomach. We also used an in vivo shortterm method for evaluating possible tumor-promoting activity with ornithine decarboxylase (ODC) as a marker. The markable inductions of the ODC activities by MNNG, NaCl, and DMI were found in the pyloric mucosa of rat stomach in time-dependent manners. A single administration of MNNG induced ODC activity up to 288 pmol $CO_2$/hr/mg protein at 24 hr after the administration. NaCl caused induction of ODC with a maximum of 179 pmol $CO_2$/hr/mg protein at 8 hr after the administration. ODC was induced up to 539 pmol $CO_2$/hr/mg protein at 16 hr after the administration of DMI. Additional treatment of NaCl and NaCl plus DMl caused 2 fold and 7 fold increases, respectively, in the ODC activity of the MNNG-alone group at 24 hr after the administration. These results suggest that NaCl and DMI have promoting activities in the rat gastric carcinogenesis initiated by MNNG.

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The Role of Stem Cells and Gap Junctional Intercellular Communication in Carcinogenesis

  • Trosko, James E.
    • BMB Reports
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    • v.36 no.1
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    • pp.43-48
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    • 2003
  • Understanding the process of carcinogenesis will involve both the accumulation of many scientific facts derived from molecular, biochemical, cellular, physiological, whole animal experiments and epidemiological studies, as well as from conceptual understanding as to how to order and integrate those facts. From decades of cancer research, a number of the "hallmarks of cancer" have been identified, as well as their attendant concepts, including oncogenes, tumor suppressor genes, cell cycle biochemistry, hypotheses of metastasis, angiogenesis, etc. While all these "hallmarks" are well known, two important concepts, with their associated scientific observations, have been generally ignored by many in the cancer research field. The objective of the short review is to highlight the concept of the role of human adult pluri-potent stem cells as "target cells" for the carcinogenic process and the concept of the role of gap junctional intercellular communication in the multi-stage, multi-mechanism process of carcinogenesis. With these two concepts, an attempt has been made to integrate the other well-known concepts, such as the multi-stage, multi-mechanisn or the "initiation/promotion/progression" hypothesis; the stem cell theory of carcinogenesis; the oncogene/tumor suppression theory and the mutation/epigenetic theories of carcinogenesis. This new "integrative" theory tries to explain the well-known "hallmarks" of cancers, including the observation that cancer cells lack either heterologous or homologous gap junctional intercellular communication whereas normal human adult stem cells do not have expressed or functional gap junctional intercellular communication. On the other hand, their normal differentiated, non-stem cell derivatives do express connexins and express gap junctional intercellular communication during their differentiation. Examination of the roles of chemical tumor promoters, oncogenes, connexin knock-out mice and roles of genetically-engineered tumor and normal cells with connexin and anti-sense connexin genes, respectively, seems to provide evidence which is consistent with the roles of both stem cells and gap junctional communication playing a major role in carcinogenesis. The integrative hypothesis provides new strategies for chemoprevention and chemotherapy which focuses on modulating connexin gene expression or gap junctional intercellular communication in the premalignant and malignant cells, respectively.

Monitoring microRNAs Using a Molecular Beacon in CD133+/CD338+ Human Lung Adenocarcinoma-initiating A549 Cells

  • Yao, Quan;Sun, Jian-Guo;Ma, Hu;Zhang, An-Mei;Lin, Sheng;Zhu, Cong-Hui;Zhang, Tao;Chen, Zheng-Tang
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.1
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    • pp.161-166
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    • 2014
  • Lung cancer is the most common causes of cancer-related deaths worldwide, and a lack of effective methods for early diagnosis has greatly impacted the prognosis and survival rates of the affected patients. Tumor-initiating cells (TICs) are considered to be largely responsible for tumor genesis, resistance to tumor therapy, metastasis, and recurrence. In addition to representing a good potential treatment target, TICs can provide clues for the early diagnosis of cancer. MicroRNA (miRNA) alterations are known to be involved in the initiation and progression of human cancer, and the detection of related miRNAs in TICs is an important strategy for lung cancer early diagnosis. As Hsa-miR-155 (miR-155) can be used as a diagnostic marker for non-small cell lung cancer (NSCLC), a smart molecular beacon of miR-155 was designed to image the expression of miR-155 in NSCLC cases. TICs expressing CD133 and CD338 were obtained from A549 cells by applying an immune magnetic bead isolation system, and miR-155 was detected using laser-scanning confocal microscopy. We found that intracellular miR-155 could be successfully detected using smart miR-155 molecular beacons. Expression was higher in TICs than in A549 cells, indicating that miR-155 may play an important role in regulating bio-behavior of TICs. As a non-invasive approach, molecular beacons could be implemented with molecular imaging to diagnose lung cancer at early stages.

The Effect of Hypnotics on Sleep Quality and Cognitive Function in Patients with Brain Tumors

  • Chang, Min Cheol;Chun, Min Ho
    • Journal of Korean Neurosurgical Society
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    • v.63 no.2
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    • pp.261-267
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    • 2020
  • Objective : We investigated the effect of hypnotics on sleep quality, cognitive function, and depressive mood in patients with insomnia following brain tumor resection. Methods : From patients who underwent brain tumor resection, we recruited 10 patients with insomnia who received hypnotics for more than 1 week during a 3-week follow-up period (insomnia group). We also recruited 12 control patients with brain tumors but without insomnia (control group). We evaluated sleep quality at baseline and 3 weeks later using the Insomnia Severity Index (ISI), the Pittsburgh Sleep Quality Index (PSQI), the Stanford Sleepiness Scale (SSS), and the Epworth Sleepiness Scale (ESS) and investigated cognitive function and depression using the Computerized Neuropsychological Test and the Beck Depression Inventory (BDI). Results : At baseline, SSS, ISI, PSQI, and BDI scores were significantly higher and visual continuous performance test (VCPT) and auditory continuous performance test (ACPT) scores were significantly lower in the insomnia than in the control group. Three weeks later, the patients who had received hypnotics had significantly higher ISI, PSQI, ESS, VCPT, ACPT, visual span forward and backward, and visual recognition test scores, and significantly lower BDI scores. Conclusion : Quality of sleep in patients with insomnia following brain tumor resection was initially poor but improved significantly after taking hypnotic medication. Further, the hypnotic medications appeared to contribute to the amelioration of cognitive impairments and depressive moods in patients who previously underwent brain tumor resection. We thus recommend the use of hypnotics for patients with brain tumors with insomnia.

제 3세대 백금착체 항암제 신약개발 2. Antitumor activity and ex vivo pharmacodynamics of SKI 2053R

  • 박재갑;홍원선;방영주;조용백;태주호;김훈택;김대기;김기협;김노경
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1993.04a
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    • pp.74-74
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    • 1993
  • The in vitro cytotoxicity of SKI 2053R was evaluated against human tumor cell lines along with those of cisplatin and carboplatin using MTT assay. The cell lines tested were two human lung cancer cell lines and five human stomach cancer celt lines. The level of cytotoxic effects of SKI 2053R against two human lung cancer cell lines was located between cisplatin and carboplatin. However, the cytotoxic activity of SKI 2053R against five human stomach cancer cell lines was similar to that of cisplatin. SKI 2053R is considered to be selectively cytotoxic toward human stomach cancer cell lines. We carried out pharmacokinetic and ex vivo phrmacodynamic studies of SKI 2053R in beagle dogs to predict the clinical antitumor effect of SKI2053R, comparing with those of cisplatin and carboplatin. In ex vivo pharmacodynamics which used MTT assay as bioassay on the 2 lung and 5 stomach cancer cell, mean antitumor indexes (ATIs) of SKI 2053R were highest among three compounds in both lung and stomach cancer cell lines, especially in stomach cancer cell. Much higher ATI profile and maximal inhibition rates of SKI 2053R appeared in the stomach cancer cells will give desirable advantages to clinical trial s against gastric carcinoma. The anti tumor activity and target organ toxicity of SKI 2053R were compared with those of cisplatin on stomach cancer cell line, KATO III xenografted into nude BALB/c(nu/nu) mice. All groups of cisplatin and SKI 2053R showed active tumor regression. The inhibition rates(IR) of SKI 2053R were higher than that of cisplatin on the basis of mean IR. Though the loss of body weight was observed in all groups from the first week, the SKI 2053R group recovered it soon from the third week after the initiation of treatment, maintaining the most active anti tumor activity among three groups.

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Thallium-201 SPECT Imaging of Brain Tumors (Thallium-201 SPECT 뇌종양 영상)

  • Kim, Sang-Eun;Choi, Chang-Woon;Lee, Dong-Soo;Chung, June-Key;Lee, Myung-Chul;Koh, Chang-Soon;Yoon, Byung-Woo;Roh, Jae-Kyu;Jung, Hee-Won
    • The Korean Journal of Nuclear Medicine
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    • v.26 no.1
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    • pp.14-25
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    • 1992
  • Thallium-201 $(^{201}T1)$ SPECT studies were performed on a normal volunteer and 12 patients with intracerebral lesions: 3 patients with gliomas, 3 patients with meningiomas, 1 patient each with metastatic tumor, brain abscess, and cerebral infarction, and 3 postirradiation patients. (2 with metastatic tumors, 1 with lymphoma). A $^{201}T1$ index, based on the ratio of $^{201}T1$ uptake in the brain lesion versus the homologous contralateral brain, was calculated and compared with tumor histology and CT/MRI findings. The SPECT $^{201}T1$ scan showed minimal uptake of tracer in a normal brain. There was substantial uptake of $^{201}T1$ in high-grade gliomas (index>1.5) with little uptake in low-grade lesions. A previously irradiated patient with recurrent astrocytoma, in whom MRI study was unable to distinguish tumor recurrence from necrosis, showed the lesions with high $^{201}T1$ indices in both hemispheric regions (2.50/1.93), suggesting tumor recurrence. Two meningiomas and a metastatic tumor showed varying degrees of $^{201}T1$ uptake (index $1.71\sim8.15$), revealing that $^{201}T1$ uptake is not exclusive to high-grade gliomas. In 2 postirradiation patients with metastatic tumors, no abnormal $^{201}T1$ uptake was found in the cerebral lesions, shortly after the initiation of radiation therapy or despite the persistence of enhancing lesions-though improved-on MR images, suggesting that $^{201}T1$ uptake may reflect the metabolic and possibly clonogenic activities of tumors and the brain $^{201}T1$ SPECT imaging might be valuable for the evaluation of tumor responsiveness to the therapy and for early detection of tumor recurrence. A patient with brain abscess on antibiotic treatment, showig increased uptake of $^{201}T1$ in the resolving lesions (index 2.87/1.52) is discussed. In a patient with cerebral infarction, there was no abnormal uptake of $^{201}T1$ in infarcted tissue. When using a threshold index of 1.5, correlation rate between $^{201}T1$ uptake and contrast enhancement of the cerebral lesions on CT/MRI was 73% (8/11). In conclusion, the brain $^{201}T1$ SPECT imaging may be useful for assessment of tumor response to the therapy and to predict low-or high-grade lesions.

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Pre-initiation treatment of indole-3-carbinol(I3C) inhibits 7,12-Dimethylbenz[α] anthracene(DMBA)-induced rat mammary carcinogenesis (Indole-3-carbinol(I3C) 투여에 의한 7,12-Dimethylbenz[α] anthracene(DMBA) 유발 랫드 유선발암 억제)

  • Kang, Jin Seok;Ahn, Byeongwoo;Nam, Ki Taek;Choi, Mina;Kim, Ji Young;Kim, Dae Joong;Jang, Dong Deuk;Yang, Ki-Hwa
    • Korean Journal of Veterinary Research
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    • v.41 no.4
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    • pp.549-555
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    • 2001
  • Indole-3-carbinol (I3C), one component of cruciferous vegetables (the Fammily of Cruciferae), has been shown to exert its chemopreventive effect in liver, colon and mammary tissue before or concurrent exposure of carcinogen, but there have been several evidences that consumption of I3C induced tumor promotion in some tissues. Our studies were investigated to examine the modifying effects of I3C in the 7,12-dimethylbenz[$\alpha$]anthracene (DMBA) induced rat mammary gland tumor model. Fifty-two female Sprague-Dawley rats were randomly divided into five groups. Animals of the group 1 were given the diet containing 100ppm I3C and animals of the groups 2 and 4 were given the diet containing 300ppm I3C from 6 weeks of age. At 7 weeks of age, the animals of the groups 1, 2 and 3 were intubated with DMBA. All amimals were killed at 20 weeks after carcinogen treatment. There were significant increases of food consumption in I3C feeding groups compared with those of basal diet feeding groups. The incidences of the mammary tumors in the group 1, 2 and 3 were 75.0% (9/12), 56.3% (9/16) and 93.8% (15/16), respectively and the average number of tumors of group 1 (DMBA+I3C 100ppm: $2.08{\pm}0.61$) and 2 (DMBA+I3C 300ppm: $1.19{\pm}0.32$) were significantly lower than that of group 3 (DMBA alone: $4.63{\pm}0.72$) at the value of P<0.05 and P<0.001, respectively. In the pathological examination of appearing tumors, most of them were adenocarcinoma. Many epithelial cells of tumors showed strong estrogen receptor (ER) $\alpha$ expression but there were slight difference of ER $\alpha$ expression among the type of tumors. We suggest that pre-initiation treatment of I3C has an inhibitory effects on mammary carcinogenesis induced by DMBA.

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Methylation Status and Immunohistochemistry of BRCA1 in Epithelial Ovarian Cancer

  • Pradjatmo, Heru;Dasuki, Djaswadi;Anwar, Mohammad;Mubarika, Sofia;Harijadi, Harijadi
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.21
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    • pp.9479-9485
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    • 2014
  • Background: Cancer initiation and progression are controlled by genetic and epigenetic events. One epigenetic process which is widely known is DNA methylation, a cause of gene silencing. If a gene is silenced the protein which it encodes will not expressed. Objectives: 1. Identify the methylation status of BRCA1 in patients with epithelial ovarian cancer (EOC)and assess BRCA1 protein expression in tumor tissue. 2. Examine whether BRCA1 gene methylation and BRCA1 protein are associated with survival of epithelial ovarian cancer patients. Methods: The study design was a prospective-cohort study, conducted at Sardjito hospital, Yogyakarta, Indonesia. Results: A total of 69 cases were analyzed in this study. The data showed that the methylation status of BRCA1 in EOC was positive in 89.9%, with clear protein expression of BRCA1 in 31.9%. Methylation status and expression of BRCA1 were not prognosticators of EOC patients. Menarche, CA125 level, clinical stage and residual tumor were independent factors for prognosis.

Autophagy in Cervical Cancer: An Emerging Therapeutic Target

  • Pandey, Saumya;Chandravati, Chandravati
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.10
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    • pp.4867-4871
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    • 2012
  • Cervical cancer is a leading cause of morbidity and mortality in women worldwide. Although the human papillomavirus (HPV) is considered the major causative agent of cervical cancer, yet the viral infection alone is not sufficient for cancer progression. The etiopathogenesis of cervical cancer is indeed complex; a precise understanding of the complex cellular/molecular mechanisms underlying the initiation, progression and/or prevention of the uterine cervix is therefore essential. Autophagy is emerging as an important biological mechanism in targeting human cancers, including cervical cancer. Furthermore, autophagy, a process of cytoplasm and cellular organelle degradation in lysosomes, has been implicated in homeostasis. Autophagic flux may vary depending on the cell/tissue type, thereby altering cell fate under stress conditions leading to cell survival and/or cell death. Autophagy may in turn govern tumor metastasis and subsequent carcinogenesis. Inflammation is a known hallmark of cancer. Vascular insufficiency in tumors, including cervical tissue, leads to depletion of glucose and/or oxygen perturbing the osmotic mileu causing extracellular acidosis in the tumor microenvironment that may eventually result in autophagy. Thus, targeted manipulation of complex autophagic signaling may prove to be an innovative strategy in identification of clinically relevant biomarkers in cervical cancer in the near future.

PRE-INITIATION TREATMENT OF INDOLE-3-CARBINOL (I3C) INHIBITS 7,12-DIMETHYLBENZ[a]ANTHRACENE(DMBA)-INDUCED RAT MAMMARY CARCINOGENESIS

  • kang, Jin-Seok;Ahn, Byeong-Woo;Lee, Kook-Kyung;Nam, Ki-Taek;Che, Jeong-Hwan;Choi, Mina;Kim, Ji-Young;Kim, Dae-Joong;Jang, Dong-Deuk;Yang, Ki-Hwa
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.10a
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    • pp.85-86
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    • 2001
  • Indole-3-carbinol (I3C), one component of cruciferous vegetables (the Family of Cruciferae), has been shown to exert chemopreventive effects in liver, colon and mammary tissue, but there has been substantial evidence that consumption of I3C induces tumor promotion in some tissues. Our studies were investigated to examine the modifying effects of I3C in the 7, 12-dimethylbenz[a]anthracene (DMBA) induced rat mammary tumor model.(omitted)

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