• 대한수의학회지
• /
• 제41권4호
• /
• pp.549-555
• /
• 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.

• 한국영양학회:학술대회논문집
• /
• 한국영양학회 1997년도 추계학술대회 초록
• /
• pp.61-61
• /
• 1997

• Toxicological Research
• /
• 제16권4호
• /
• pp.275-284
• /
• 2000

The organ culture model of the whole mammary gland has many advantages for the study of branching morphogenesis and biological characteristics, including tumorigenesis. Prior to whole gland organ culture, rats were treated with 7,12-dimethylbenz[a]anthracene (DMBA) or N-methyl-N-nitrosourea (MNU) for one week. The tramdorming effect and the morphological changes were assessed by the whole mount preparations and histopathological examination in terminal end buds (TEB), terminal ducts (TD), alveolar buds (AB), alveolar lobules (AL) and hyperplastic alveolar nodules (HAN) of the mammary gland. Grossfindings of the mammary glands at dissection were higher branching morphogenesis and larger volume in carcinogen-treated groups than in carcinogen-non-treated groups. Results of the whole mount method were coincided with those of the histopathological observations. Circular TEB, normally maintained AB, AL, and high cellular density were more frequently observed in carcinogen-treated groups than in carcinogen-nan-treated groups. Histopathologically, as a preneoplastic marker, HAN was maintained only in mammary organ culture of the carcinogen-treated groups. These findings suggest that in vivo trans-formation effects by carcinogens persisted during the mammary organ culture. These results were more characteristic in DMBA than in MNU-treated group. Ducts and terminal ducts appeared to have lost morphology during their growths in case of without diethylstilbestrol (DES). The fact that in vitro organ culture without DES was resulted in abnormal ductular morphogenesis confirms that DES is a physiological regulator of ductular epithelial cell growth.

• Nutritional Sciences
• /
• 제9권1호
• /
• pp.14-19
• /
• 2006

Breast cancer may be the consequence of free radical damage, which is partially caused by the excessive intake of dietary fat and imbalances in antioxidant scavenger system;. In this experiment, we examined! the effects of dietary peroxidizability index (PI) values on hepatic thiobmbituric acid reaction substances (TBARS) and antioxidant enzyme activities in rats treated with 7,12-dimethylbenz[$\alpha$]anthracene (DMBA). Female Sprague-Dawley rats were used and 7,12-DMBA (20 mg/kg body weight) was gastrically intubated at seven weeks of age in order to induce mammary tumors (MT). The levels of dietary PI were 36, 81, 126 and 217 (LPI, MLPI, MHPI and HPI), while dietary polyunsaturated/saturated fatty acids ratio was maintained at the same level (1.0). Fat used in the experiment was mixed with soybean oil, com oil, palm oil, perilla oil, sesame oil, fish oil, and beef tallow. Experimental diets were given for the following 20 weeks. We measured tumor numbers and weights, and then assayed the hepatic TBARS levels and antioxidant enzyme activities such as superoxide dismutase (SOD), catalase, glutathione peroxidase, glutathione-S-transferase (GST) and glutathione reductase (GR). The incidence of Mr was the lowest in the MHPI group. The hepatic TBARS level was significantly raised with increasing dietary PI value. The hepatic SOD and GR activities were differed significantly by dietary PI value. The hepatic SOD activity was negatively correlated with dietary PI value and GR activity was the highest in the rats fed the MHPI diet. When the dietary P/S ratio is kept at 1.0, adequate dietary PI value (PI value of 126) may reduce the incidence and growth of Mr, but this benefit may be lost with higher dietary PI value. These results suggest that the awareness of dietary PI values may help to decrease breast cancer incidence and growth.

• Asian Pacific Journal of Cancer Prevention
• /
• 제17권1호
• /
• pp.117-123
• /
• 2016

Taxol (paclitaxel) is a powerful anti-cancer drug widely used against several types of malignant tumors. Because Taxol may exert several side effects, a variety of formulations have been developed. One of these features liposomes, regarded as one of the most promising drug carriers, biocompatible and best able to reduce drug toxicity without changing efficacy against tumor cells. Eruca sativa seed extract (SE) is considered a promising natural product from cruciferous vegetables against breast cancer, increasing chemotherapeutic and eliminating harmful side effects. The effects of Taxol-encapsulated liposomes (T) alone and in combination between Eruca sativa seed extract on nuclear factor kappa B (NF-${\kappa}B$), cyclooxygenase-2 (COX-2) and B-cell lymphoma-2 (Bcl-2) gene expression levels were investigated in rat mammary gland carcinogenesis induced by 7,12 dimethylbenz(${\alpha}$) anthracene (DMBA) using qRT-PCR. The results showed that DMBA increased NF-${\kappa}B$, COX-2 and Bcl-2 gene expression levels and lipid peroxidation (LP), while decreasing glutathione-S-transferase (GST) and superoxide dismutase (SOD) activities and total antioxidant concentration (TAC) compared to the control group. T and T-SE treatment reduced NF-${\kappa}B$, COX-2 and Bcl-2 gene expression levels and LP. Hence, T and T-SE treatment appeared to reduce inflammation and cell proliferation, while increasing apoptosis, GST and SOD activities and TAC.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권6호
• /
• pp.2533-2539
• /
• 2012

Annona muricata L (Annonaceae), commonly known as soursop has a long, rich history in herbal medicine with a lengthy recorded indigenous use. It had also been found to be a promising new anti-tumor agent in numerous in vitro studies. The present investigation concerns chemopreventive effects in a two-stage model of skin papillomagenesis. Chemopreventive effects of an ethanolic extract of A. muricata leaves (AMLE) was evaluated in 6-7 week old ICR mice given a single topical application of 7,12-dimethylbenza(${\alpha}$)anthracene (DMBA 100ug/100ul acetone) and promotion by repeated application of croton oil (1% in acetone/twice a week) for 10 weeks. Morphological tumor incidence, burden and volume were measured, with histological evaluation of skin tissue. Topical application of AMLE at 30, 100 and 300mg/kg significantly reduced DMBA/croton oil induced mice skin papillomagenesis in (i) peri-initiation protocol (AMLE from 7 days prior to 7 days after DMBA), (ii) promotion protocol (AMLE 30 minutes after croton oil), or (iii) both peri-initiation and promotion protocol (AMLE 7 days prior to 7 day after DMBA and AMLE 30 minutes after croton oil throughout the experimental period), in a dose dependent manner (p<0.05) as compared to carcinogen-treated control. Furthermore, the average latent period was significantly increased in theAMLE-treated group. Interestingly, At 100 and 300 mg/kg, AMLE completely inhibited the tumor development in all stages. Histopathological study revealed that tumor growth from the AMLE-treated groups showed only slight hyperplasia and absence of keratin pearls and rete ridges. The results, thus suggest that the A.muricata leaves extract was able to suppress tumor initiation as well as tumor promotion even at lower dosage.

• Molecules and Cells
• /
• 제39권3호
• /
• pp.266-279
• /
• 2016

The mechanism by which 12-O-tetradecanoylphorbol-13-acetate (TPA) bypasses cellular senescence was investigated using human diploid fibroblast (HDF) cell replicative senescence as a model. Upon TPA treatment, protein kinase C (PKC) ${\alpha}$ and $PKC{\beta}1$ exerted differential effects on the nuclear translocation of cytoplasmic pErk1/2, a protein which maintains senescence. $PKC{\alpha}$ accompanied pErk1/2 to the nucleus after freeing it from $PEA-15pS^{104}$ via $PKC{\beta}1$ and then was rapidly ubiquitinated and degraded within the nucleus. Mitogen-activated protein kinase docking motif and kinase activity of $PKC{\alpha}$ were both required for pErk1/2 transport to the nucleus. Repetitive exposure of mouse skin to TPA downregulated $PKC{\alpha}$ expression and increased epidermal and hair follicle cell proliferation. Thus, $PKC{\alpha}$ downregulation is accompanied by in vivo cell proliferation, as evidenced in 7, 12-dimethylbenz(a)anthracene (DMBA)-TPA-mediated carcinogenesis. The ability of TPA to reverse senescence was further demonstrated in old HDF cells using RNA-sequencing analyses in which TPA-induced nuclear $PKC{\alpha}$ degradation freed nuclear pErk1/2 to induce cell proliferation and facilitated the recovery of mitochondrial energy metabolism. Our data indicate that TPA-induced senescence reversal and carcinogenesis promotion share the same molecular pathway. Loss of $PKC{\alpha}$ expression following TPA treatment reduces pErk1/2-activated SP1 biding to the $p21^{WAF1}$ gene promoter, thus preventing senescence onset and overcoming G1/S cell cycle arrest in senescent cells.

• 한국독성학회:학술대회논문집
• /
• 한국독성학회 2001년도 International Symposium on Signal transduction in Toxicology
• /
• pp.145-145
• /
• 2001

Xanthorrhizol is a sesquiterpenoid isolated from Curcuma xanthorrhiza Roxb. (Zingiberaceae) that has been traditionally used in Indonesia for dietary and medicinal purposes. In our studies to evaluate the cancer chemopreventive potential, xanthorrhizol inhibited the mutagenesis induced by reactive oxygen species in Sa;monella typhimurium TA 102 in a dose-related manner and decreased significantly the incidence and the multiplicity of skin tumors initiated by 7, 12-dimethylbenz[$\alpha$]anthracene and promoted by 12-Ο-tetradecanoylphorbol-13-acetate at 19 weeks.(omitted)

• 대한약리학회지
• /
• 제28권2호
• /
• pp.213-222
• /
• 1992

Benzopyrene (BP), 7,12-dimehyl benzanthracene (DMBA), nitrosomethyl urea (NUMU) 및 nicotine과 같은 발암성 화학물질들이 바이러스 감염된 vero 세포의 단층 세포 배양에서 I형 단순성포진 바이러스 (HSV-1)의 복제, 세포융해, DNA합성 및 단백질 합성에 미치는 효과를 관찰하였다. 1. BP와 DMBA는 HSV-1의 복제와 세포융해작용을 유의성있게 억제하였으나 nicotine과 NMU는 별로 억제하지 않았다. 2. 모든 발암성 화학물질은 바이러스의 DNA합성을 억제하지 못하였지만 새로 합성되는 후손바이러스 DNA로 부터 표현되는 gamma 단백질의 표현은 BP와 DMBA에 의해서 현저하게 억제되었다. 그러나 모든 발암성 화학물질은 바이러스의 alpha 및 beta 단백질의 합성은 억제하지 못하였다. 이상의 결과로 보아 발암성화학물질이 존재하고 있는 배지내에서 새로 합성되는 바이러스의 DNA로 부터 표현되는 gamma 단백질의 결함이 있음을 알 수가 있었으며 이같은 개념은 발암화학물질의 존재하에서 바이러스의 DNA와 단백질이 거의 정상적으로 합성됨에도 불구하고 바이러스의 복제가 일어나지 않는다는 사실이 뒷받침해주고 있다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제14권4호
• /
• pp.2249-2254
• /
• 2013

The study was conducted to determine the effect of Malaysian jungle Tualang Honey (TH) on development of breast cancer induced by the carcinogen 7,12-dimethylbenz(${\alpha}$)anthracene (DMBA) in rats. Forty nulliparous female Sprague-Dawley rats were given 80 mg/kg DMBA then randomly divided into four groups: Group 1 served as a Control while Groups 2, 3 and 4 received 0.2, 1.0 or 2.0 g/kg bodyweight/day of TH, respectively, for 150 days. Results showed that breast cancers in the TH-treated groups had slower size increment and smaller mean tumor size (${\leq}2cm^3$) compared to Controls (${\leq}8cm^3$). The number of cancers developing in TH-treated groups was also significantly fewer (P<0.05). Histological grading showed majority of TH-treated group cancers to be of grade 1 and 2 compared to grade 3 in controls. There was an increasing trend of apoptotic index (AI) seen in TH-treated groups with increasing dosage of Tualang Honey, however, the mean AI values of all TH-treated groups were not significantly different from the Control value (p>0.05). In conclusion, Tualang Honey exerted positive modulation effects on DMBA-induced breast cancers in rats in this preliminary study.