Effect and mechanism of Xihuang Pills on rats with precancerous lesions of breast / 中国中药杂志

The purpose of this study was to explore the effect and mechanism of Xihuang Pills on rats with precancerous lesions of the breast. Of 48 healthy female rats, 8 were randomly selected as blank group, and the other 40 were treated with 7,12-dimethylbenzanthracene(DMBA) combined with estrogen and progestin to establish a model of precancerous lesions of the breast. The successfully modeled rats were randomly divided into a model group, a tamoxifen group(1.8 mg·kg~(-1)·d~(-1)), a Xihuang Pills low-dose group(0.3 g·kg~(-1)·d~(-1)), a medium-dose group(0.6 g·kg~(-1)·d~(-1)) and a high-dose group(1.2 g·kg~(-1)·d~(-1)). After 30 days of admi-nistration, the histopathological changes of viscera and breast were observed by haematoxylin and eosin(HE) staining, and the visceral index was calculated. Enzyme linked immunosorbent assay(ELISA) was used to detect the contents of estradiol(E_2) and progesterone(P) in serum. The protein expressions of vascular endothelial growth factor(VEGF) and fibroblast growth factor 2(FGF2) were detected by immunohistochemistry. The protein expressions of VEGF, vascular endothelial growth factor receptor 2(VEGFR2), phosphorylated-vascular endothelial growth factor receptor 2(p-VEGFR2), B-cell lymphoma-2(Bcl-2), and Bcl-2 associated X protein(Bax) were detected by Western blot and the mRNA expressions of VEGF, FGF2, CXC-chemokine receptor 4(CXCR4), cysteine aspartic acid-specific protease(caspase-3), and stromal cell-derived factor 1(SDF-1) were detected by real-time polymerase chain reaction(RT-PCR). HE staining revealed that the model group had some liver and kidney damages and severe hyperplastic mammary tissue, while the Xihuang Pills high-dose group had mild hyperplasia. Compared with the model group, the Xihuang Pills groups had lo-wer ovarian coefficient(P<0.05 or P<0.01) and Xihuang Pills high-dose group had lower uterine coefficient(P<0.01). ELISA results showed that compared with the model group, expressions of E_2 and P in Xihuang Pills high-dose group were significantly decreased(P<0.05 or P<0.01). Immunohistochemistry, Western blot and RT-PCR indicated that compared with the conditions in the model group, the protein and mRNA expressions of VEGF and FGF2 in the Xihuang Pills groups were down-regulated(P<0.05 or P<0.01), and the protein expression of Bcl-2 was lowered(P<0.01); there was a decrease in the protein expressions of VEGFR2 and p-VEGFR2(P<0.01), a down-regulation in the mRNA expressions of CXCR4 and SDF-1(P<0.01), while an increase in the mRNA expression of caspase-3(P<0.01) in both Xihuang Pills medium-dose and high-dose groups; the protein expression of Bax in Xihuang Pills high-dose group was increased(P<0.01). The above results indicated that Xihuang Pills can effectively intervene in precance-rous lesions of the breast, and the mechanism may be related to the regulation of E_2 and P secretion as well as the inhibition of angiogenesis and chemokine receptor expression, thus controlling the occurrence of precancerous lesions of the breast in rats.

Effect of Thymoquinone on skeletal muscle regeneration via assessment of Pax-7 and Myo-D expression in the DMBA-treated hamster pouch / Efeito da Timoquinona na regeneração muscular esquelética através da avaliação da expressão das proteínas Pax-7 e Myo-D em bolsa jugal de hamsters tratados com DMBA

Objective: Pax-7 and Myo-D regulate satellite cells' activation and differentiation, thus muscle regeneration following damage. This research aimed to investigate the effect of Thymoquinone (TQ) on skeletal muscle regeneration following 7,12-dimethylbenz-(a)-anthracene (DMBA)-induced injury in the hamster buccal pouch via immunohistochemical assessment of Pax-7 and Myo-D expression. Material and Methods: 65 male golden Syrian hamsters were divided into 3 groups: Group 1: (n=5) received no treatment. Group 2: (n=20) served as a positive control. The left buccal pouches were painted with the carcinogen 3/week/ 6weeks. Group 3: (n=40) were subdivided into two equal sub-groups as follows: Group 3a: (n=20) were given one i.p. TQ injection. Group 3b: (n=20) were given two i.p. TQ injections. Five animals from each group (2 and 3) were euthanized at 24, 48 hrs, one, and two weeks after the last injection. A blood sample (2 ml) was withdrawn for assessment of TNF-α levels in serum. Serial sections of the pouches were examined histologically (H&E), and immunohistochemically (IHC) for the detection of Pax-7 and Myo-D proteins. Results: double i.p injections of TQ resulted in a significant elevation in the level of TNF-α from the second-day post-injection with a progressive formation of the muscle fibers (MFs) and mononuclear cells (MNCs) around the deeper blood vessels. At 14 days, no statistically significant difference was found between this group and group '2', while the difference remained significant compared to groups '1' and '3a'. The muscle fibers were more mature and compact. IHC results showed positive expression of the perivascular mononuclear cells (MNCs) to both Pax-7 and Myo-D with positive reactivity of the peripheral nuclei of muscle fibers to Pax-7 compared to the negative reaction in the positive control group. Conclusion: early and two TQ injections had a promising effect on the induction of striated muscle regeneration, mainly by non-myogenic stem cells (AU)

Objetivo: Pax-7 e Myo-D regulam a ativação e diferenciação de células satélites durante a regeneração muscular pós-trauma. Assim, objetivamos investigar o efeito da timoquinona (TQ) na regeneração muscular esquelética após injúria causada por 7,12 dimetilbenzantraceno (DMBA) em bolsa jugal de hamsters, através da análise imuno-histoquímica de Pax-7 e Myo-D. Material e Métodos: 65 hamsters-sírios machos foram divididos em 3 grupos: Grupo 1: (n=5) controle negativo, sem tratamento. Grupo 2: (n=20) controle positivo. A bolsa jugal do lado esquerdo recebeu aplicação do DMBA por 3 e 6 semanas. Grupo 3: (n=40) receberam aplicação de DMBA e foram então subdivididos em: Grupo 3a: (n=20) que recebeu 1 injeção intraperitoneal (ip) de TQ e Grupo 3b: (n=20) que recebeu duas injeções ip de TQ. Cinco animais dos grupos 2 e 3 foram eutanasiados em 24 horas, 48 horas, 7 dias e 14 dias após a administração de DMBA e da última injeção de TQ. Amostras de sangue (2 ml) foram coletadas para avaliação dos níveis séricos de TNF-α. Cortes seriados da bolsa jugal dos animais foram analisados histologicamente (H&E), e através de imunohistoquimica (IHC) para avaliação das proteínas Pax-7 e Myo-D. Resultados: duas injeções ip de TQ aumentaram os níveis séricos TNF-α à partir do segundo dia pós-administração com formação progressiva de fibras musculares (MFs) e células mononucleares (MNCs) ao redor dos vasos sanguíneos. No dia 14, não houve diferença estatística entre o grupo 3b e o grupo 2, enquanto a diferença permaneceu entre o grupo 1 e 3a. As MFs apresentavam-se mais maduras e compactas. A IHC mostrou expressão de Pax-7 e Myo-D nas MNCs ao redor dos vasos, e houve expressão nuclear de Pax-7 nas MFs no grupo 2. Conclusão: ambos regimes de administração do TQ, 1 ou 2 aplicações ip, apresentaram efeito promissor na indução da regeneração muscular esquelética, principalmente nas células não-miogênicas.(AU)

Chemopreventive agents on a mouse skin carcinogenesis model: an integrative review / Agentes quimiopreventivos em um modelo de carcinogênese de pele em camundongos: uma revisão integrativa / Agentes quimiopreventivos en un modelo de carcinogénesis cutánea en ratón: una revisión integradora

Squamous cell carcinoma (SCC) is a non-melanoma skin cancer, with chronic sun exposure as the main risk factor. Excisional surgery is the most indicated treatment; however, patients can suffer functional, aesthetic, and psychological damage depending on the lesion site. Topical administration of 7,12-dimethylbenz[a]anthracene (DMBA) and 12-O-Tetradecanoylphorbol-13- acetate (TPA) induce to the appearance of benign skin tumors in mice, some of which develop into SCC. This protocol has been used to analyze the effects of many chemopreventive agents that may block or inhibit the mechanisms of action of chemical carcinogenesis. We compared the effects of chemopreventive agents in an induced skin carcinogenesis animal model. In the Scopus, PubMed, and EMBASE databases, we searched for manuscripts published between June 16, 2011, and June 16, 2021. We excluded studies conducted in vitro or on transgenic mice; in addition, studies without drug dosage, route of administration, or tumor incidence were excluded. We selected 26 studies and analyzed their main characteristics and the outcomes of tumorigenesis analysis. Most chemopreventive agents have shown excellent potential to inhibit the development of skin tumors. This review also discusses the standardization of studies in animal models to ensure better responses and future randomized clinical trials for cancer treatment and prevention.

O carcinoma espinocelular cutâneo (CEC) é um câncer de pele não melanoma, com a exposição solar crônica como o principal fator de risco. A cirurgia excisional é o tratamento mais indicado; entretanto, os pacientes podem sofrer danos funcionais, estéticos e psicológicos dependendo do local da lesão. A administração tópica de 7,12-dimetilbenz[a]antraceno (DMBA) e 12-O- Tetradecanoilforbol-13-acetato (TPA) induz ao aparecimento de tumores cutâneos benignos em camundongos, alguns dos quais evoluíram para CEC. Este protocolo tem sido utilizado para analisar os efeitos de muitos agentes quimiopreventivos que podem bloquear ou inibir os mecanismos de ação da carcinogênese química. Comparamos os efeitos de agentes quimiopreventivos em um modelo animal que foi induzido à carcinogênese de pele. Nas bases de dados Scopus, PubMed e EMBASE, buscamos manuscritos publicados entre 16 de junho de 2011 e 16 de junho de 2021. Excluímos estudos realizados in vitro ou em camundongos transgênicos; além disso, estudos sem dosagem de drogas, via de administração ou incidência de tumores foram excluídos. Selecionamos 26 estudos e analisamos suas principais características e os resultados da análise da tumorigênese. A maioria dos agentes quimiopreventivos tem demonstrado excelente potencial para inibir o desenvolvimento de tumores cutâneos. Esta revisão também discute a padronização de estudos em modelos animais para garantir melhores respostas e futuros ensaios clínicos randomizados para tratamento e prevenção do câncer.

El carcinoma de células escamosas (CCE) es un cáncer de piel no melanoma, cuyo principal factor de riesgo es la exposición crónica al sol. La cirugía de escisión es el tratamiento más indicado; sin embargo, los pacientes pueden sufrir daños funcionales, estéticos y psicológicos dependiendo de la localización de la lesión. La administración tópica de 7,12-dimetilbenz[a]antraceno (DMBA) y 12-O-Tetradecanoilforbol-13-acetato (TPA) inducen a la aparición de tumores cutáneos benignos en ratones, algunos de los cuales se convierten en CCE. Este protocolo se ha utilizado para analizar los efectos de muchos agentes quimiopreventivos que pueden bloquear o inhibir los mecanismos de acción de la carcinogénesis química. Comparamos los efectos de los agentes quimiopreventivos en un modelo animal de carcinogénesis cutánea inducida. En las bases de datos Scopus, PubMed y EMBASE, se buscaron los manuscritos publicados entre el 16 de junio de 2011 y el 16 de junio de 2021. Se excluyeron los estudios realizados in vitro o en ratones transgénicos; además, se excluyeron los estudios sin dosis de fármacos, vía de administración o incidencia tumoral. Se seleccionaron 26 estudios y se analizaron sus características principales y los resultados del análisis de la tumorigénesis. La mayoría de los agentes quimiopreventivos han mostrado un excelente potencial para inhibir el desarrollo de tumores cutáneos. Esta revisión también analiza la estandarización de los estudios en modelos animales para garantizar mejores respuestas y futuros ensayos clínicos aleatorios para el tratamiento y la prevención del cáncer.

Experimental carcinogenesis with 7, 12-dimethylbenz(a)anthrazene (DMBA) and its inhibition with isothi-ocyanates / Carcinogénesis experimental con 7, 12-dimetilbenzantraceno (DMBA) y su inhibición con isitiocianatos

Introduction: DMBA is a chemical carcinogen that induces carcinomas within a few weeks of its application. We developed an experimental model of carcinogenesis induced by DMBA dissolved in 0,5% paraffin oil (DMBA-PO), verifying the inhibitory effect of the carcinogenicity of phenyl isothiocyanate (PhITC), phenethyl (PhnITC) and benzyl isothiocyanate (BITC). Material and Methods: For this, 88 hamsters were distributed into three groups: one exposed to DMBA-PO (Group 1, n=12), three subgroups (n=12) exposed to PhITC, PhnITC, BITC and DMBA-PO (Group 2, n=36) and four control subgroups (n=10) that were not exposed to the carcinogen in which PO (paraffin oil) and isothiocyanates were applied (Group 3, n=40). Results: The experiment had a duration of 20 weeks, at the end of which the inhibitory effect was established by comparing the lesions developed in the groups that received isothiocyanates with the group that was only treated with DMBA-PO. The carcinogenic effect of DMBA-PO is 100% (35 carcinomas) and the inhibitory effect was 0, whereas in the presence of isothiocyanates the carcinogenic effect decreases, with an inhibitory effect of 86% for BITC (5 carcinomas) and 74% for PhITC (9 carcinomas). Conclusion: The inhibitory effect for PhnITC is 80% in relation to invasive OSCC (1 carcinoma).

Introducción: El DMBA es un carcinógeno químico que induce carcinomas a las pocas semanas de su aplicación. Desarrollamos un modelo experimental de carcinogénesis inducida por DMBA disuelto en aceite de parafina al 0,5% (DMBA-Ap) comprobando el efecto inhibidor de la carcinogénesis de los isotiocianatos fenil (PhITC), fenetil (PhnITC) y bencil isotiocianato (BITC). Material y Métodos: Para ello, se distribuyeron 88 hámsteres en 3 grupos: uno expuesto al DMBA-Ap (Grupo 1, n=12), tres subgrupos (n=12) expuestos a PhITC, PhnITC, BITC y DMBA-Ap (Grupo 2, n=36) y cuatro subgrupos controles (n=10), no expuestos al carcinógeno en el que se aplicaron Ap e isotiocianatos (Grupo 3, n=40). Resultados:El experimento tuvo una duración de 20 semanas, al final de la cual se establece de forma comparativa el efecto inhibidor comparando las lesiones desarrolladas en los grupos que recibieron isotiocianatos con respecto al grupo tratado sólo con DMBA-Ap. El efecto carcinógeno del DMBA-Ap es del 100% (35 carcinomas) y el efecto inhibidor 0, mientras que en presencia de isotiocianatos el efecto carcinógeno disminuye, con un efecto inhibidor del 86% para BITC (5 carcinomas) y del 74% para el PhITC (9 carcinomas). Conclusión:El efecto inhibidor del PhnITC es del 80% en relación con el COCE invasivo (1 carcinoma).

Concomitant using of topical carrageenan-kappa and oral vitamin D against 7, 12-dimethylbenz[a]anthracene induced-oral cancer in rats: A synergism or an antagonism effects / Uso concomitante de carragenina tópica e vitamina D oral contra câncer de boca em ratos induzido por 7, 12-dimetilbenz(a) antraceno: efeitos sinérgicos ou antagonistas

Objective: κ-carrageenan is a food stabilizer agent which has an antiproliferative effect, while vitamin D is a prohormone acts on the nuclear receptor and has a cytotoxic against cancer. This study aimed to show the synergistic effect of using topical κ-carrageenan and oral administration of the vitamin D on the 7, 12-dimethylbenz[a] anthracene (DMBA)-induced oral cancer. Material and Methods: fifty four male albino rats were randomly divided into seven groups: Acetonetreated served as control (Group I), vitamin D (5000UI)-treated (Group II), κ-carrageenan (1%)- treated (Group III), DMBA (0.5%)-treated (Group IV), Acetone, κ-carrageenan and DMBA were administered topically on both cheeks and palate, five times weekly for 12 weeks, while the vitamin D was administered orally twice weekly for 12 weeks. Groups V, VI, and VII were animals treated with vitamin D, κ-carrageenan, and both vitamin D and κ-carrageenan for 8 weeks after induction of oral cancer. At the end of the study, blood samples were obtained by cardiac puncture for determination of TNF-α and EGFR. Results: In the groups III and IV, serum EGFR showed significant low levels compared with Group I. In the Group VII, serum EGFR showed a significantly (p=0.014) low level compared with Group IV (614.3±69.7 pg/ml versus 882.4±45.6 pg/ml, respectively). Higher percentages of high levels of TNF-α were observed in the Groups VI and VII, while a lower percentage of EGFR was observed in the Group VI. Conclusion: both κ-carrageenan and vitamin D have antiproliferative effect against DMBAinducing oral cancer by increasing the levels of TNF-α and suppressing the signaling pathway of EGFR. Concomitant using κ-carrageenan and vitamin D reduces the antiproliferative effect of each other.(AU)

Objetivo: κ-carragenina é um agente estabilizador de alimentos que tem efeito um antiproliferativo, enquanto a vitamina D é um pró-hormônio que atua sobre o receptor nuclear e possui efeito citotóxico contra o câncer. Este estudo teve como objetivo mostrar o efeito sinérgico do uso de κ-carragenina tópica e administração oral da vitamina D no câncer de boca induzido por 7, 12-dimetilbenz[a]antraceno (DMBA). Material e Métodos: cinquenta e quatro ratos albinos machos foram divididos aleatoriamente em sete grupos: tratado com acetona como controle (Grupo I), tratado com vitamina D (5000UI) (grupo II), tratado com κ-carragenina (1%) (grupo III), DMBA (0,5%) tratado (Grupo IV), acetona, κ-carragenina e DMBA foram administrados topicamente nas bochechas e no palato, cinco vezes por semana durante 12 semanas, enquanto a vitamina D foi administrada por via oral duas vezes por semana durante 12 semanas. Os grupos V, VI e VII foram animais tratados com vitamina D, κ-carragenina e No final do estudo, foram obtidas amostras de sangue por punção cardíaca para determinação do TNF-α e EGFR. Resultados: Nos grupos III e IV, o EGFR sérico mostrou níveis baixos significativos em comparação com o Grupo I. No grupo VII, o EGFR sérico mostrou um nível significativamente baixo (p = 0,014) em comparação com o Grupo IV (614,3 ± 69,7 pg / ml versus 882,4 ± 45,6 pg / ml, respectivamente). Maiores porcentagens de TNF-α foram observadas nos Grupos VI e VII, enquanto uma menor porcentagem de EGFR foi observada no Grupo VI. Conclusão: Tanto a κ-carragenina quanto a vitamina D têm efeito antiproliferativo contra o câncer de boca induzido por DMBA aumentando os níveis de TNF-α e suprimindo a via de sinalização do EGFR. O uso concomitante de κ-carragenina e a vitamina D reduz o efeito antiproliferativo um do outro (AU)

Effect of Arrabidaea chica extract against chemically induced breast cancer in animal model

Abstract Purpose: To examine the effects of Arrabidaa chica (Bignoniacea) extract, a native plant of the Amazon known as crajiru, on a 7,12-dimethyl-1,2-benzanthracene (DMBA)-induced breast cancer model in Wistar rats. Methods: We compared the response of breast cancer to the oral administration of A. chica extract (ACE) for 16 weeks, associated or not with vincristine. Groups: normal control; DMBA (50mg/kg v.o,) without treatment; DMBA+ACE (300 mg/kg); DMBA+vincristine. 500μg/kg injected i.p; DMBA+ACE+Vincristine 250μg/kg i.p. Imaging by microPET and fluorescence, biochemistry, oxidative stress, hematology and histopathology were used to validate the treatments. Results: All animals survived. A gradual weight gain in all groups was observed, with no significant difference (p>0.05). The oral administration of ACE and ACE+vincristine 50% significantly reduced breast tumors incidence examined with PET-18FDG and fluorescence (p<0.001). Significant reduction of serum transaminases, oxidative stress and hematological toxicity were observed in these groups. Antioxidant enzyme levels in breast tissue were significantly higher compared to the DMBA and DMBA+vincristine groups. Conclusion: These results demonstrate for the first time that ACE positively influences the treatment of DMBA-induced breast cancer in animal model, inducing a reduction in oxidative stress and chemotherapy toxicity, meaning that ACE may have clinical implication in further studies.

Successful development of squamous cell carcinoma and hyperplasia in RGEN-mediated p27 KO mice after the treatment of DMBA and TPA / 한국실험동물학회지

To evaluate the carcinogenicity of p27 knockout (KO) mice with RNA-guided endonuclease (RGENs)-mediated p27 mutant exon I gene (IΔ), alterations in the carcinogenic phenotypes including tumor spectrum, tumor suppressor proteins, apoptotic proteins and cell cycle regulators were observed in p27 (IΔ) KO mice after treatment with 7,12-Dimethylbenz[a]anthracene (DMBA) and 12-O-tetradecanoylphorbol-13-acetate (TPA)(DT) for 5 months. The target region (544~571 nt) in exon I of the p27 gene was successfully disrupted in p27 (IΔ) KO mice using the RGEN-induced non-homologous end joining (NHEJ) technique. After DT exposure for 5 months, a few solid tumors (identified as squamous cell carcinoma) developed on the surface of back skin of DT-treated p27 (IΔ) KO mice. Also, squamous cell hyperplasia with chronic inflammation was detected in the skin dermis of DT-treated p27 (IΔ) KO mice, while the Vehicle+p27 (IΔ) KO mice and WT mice maintained their normal histological skin structure. A significant increase was observed in the expression levels of tumor suppressor protein (p53), apoptotic proteins (Bax, Bcl-2 and Caspase-3) and cell-cycle regulator proteins (Cyclin D1, CDK2 and CDK4) in the skin of DT-treated p27 (IΔ) KO mice, although their enhancement ratio was varied. Taken together, the results of the present study suggest that squamous cell carcinoma and hyperplasia of skin tissue can be successfully developed in new p27 (IΔ) KO mice produced by RGEN-induced NHEJ technique following DT exposure for 5 months.

Establishment of a rat model of dimethylbenzanthracene-induced vulvar squamous intraepithelial lesions / 南方医科大学学报

OBJECTIVE@#To establish a SD rat model of vulvar squamous intraepithelial lesions.@*METHODS@#Seventy female SD rats were randomized into 4 groups, namely the blank control group (=10), mechanical irritation group (=10), acetone solution group (=10), and mechanical irritation with DMBA acetone solution group (=40, model group), and the corresponding treatments were administered 3 times a week for 14 weeks. The changes of the vulvar skin of the rats were observed regularly until the 18th week. The expression of mutant p53 (mtp53) and vascular endothelial growth factor (VEGF) proteins were detected using immunohistochemistry and Western blotting, and the expressions of mtp53 and VEGF mRNA were detected with qRT- PCR in the blank control group and model group.@*RESULTS@#No significant differences were found in the morphological or histopathological changes of the skin among the blank control group, mechanical irritation group and acetone solution group. In the model group, low-grade squamous intraepithelial lesions (LSIL) occurred in 28 rats (70%) and high-grade squamous intraepithelial lesions (HSIL) in 11 rats (27.5%) at 14 weeks, with a success rate of 97.5% in inducing vulvar squamous intraepithelial lesions. Compared with the blank control group, the rats in the model group showed significantly increased expressions of mtp53 and VEGF at both the protein level ( < 0.05) and the mRNA level ( < 0.05).@*CONCLUSIONS@#DMBA in acetone solution combined with mechanical irritation can induce vulvar squamous intraepithelial lesions in female SD rats.

Circadian rhythm variation of the clock genes Per1 and cell cycle related genes in different stages of carcinogenesis of buccal mucosa in animal model / 中华口腔医学杂志

<p><b>OBJECTIVE</b>To investigate the expression and circadian rhythm variation of biological clock gene Per1 and cell cycle genes p53, CyclinD1, cyclin-dependent kinases (CDK1), CyclinB1 in different stages of carcinogenesis in buccal mucosa and its relationship with the development of buccal mucosa carcinoma.</p><p><b>METHODS</b>Ninety golden hamsters were housed under 12 hours light-12 hours dark cycles, and the model of buccal squamous cell carcinoma was established by using the dimethylbenzanthracene (DMBA) to smear the golden hamster buccal mucosa. Before the DMBA was used and after DMBA was used 6 weeks and 14 weeks respectively, the golden hamsters were sacrificed at 6 different time points (5 rats per time point) within 24 hour, including 4, 8, 12, 16, 20 and 24 hour after lights onset (HALO), and the normal buccal mucosa, precancerous lesions and cancer tissue were obtained, respectively. HE stained sections were prepared to observe the canceration of each tissue. Real time RT-PCR was used to detect the mRNA expression of Per1, p53, CyclinD1, CDK1 and CyclinB1, and a cosine analysis method was applied to determine the circadian rhythm variation of Per1, p53, CyclinD1, CDK1 and CyclinB1 mRNA expression, which were characterized by median, amplitude and acrophase.</p><p><b>RESULTS</b>The expression of Per1, p53, CDK1 and CyclinD1 mRNA in 6 different time points within 24 hours in the tissues of three different stages of carcinogenesis had circadian rhythm, respectively. However, the CyclinB1 mRNA was expressed with circadian rhythm just in normal and cancer tissue (P < 0.05), while in precancerous lesions the circadian rhythm was in disorder (P > 0.05). As the development of carcinoma, the median of Per1 and p53 mRNA expression were significantly decreased (P < 0.05), yet the median of CDK1, CyclinB1 and CyclinD1 mRNA expression were significantly increased (P < 0.05). The amplitude of Per1, p53 and CyclinD1 mRNA expression was significantly decreased as the development of carcinoma (P < 0.05), however the amplitude of CDK1 mRNA expression was significantly increased (P < 0.05). In addition, there was no significant difference in the amplitude of CyclinB1 mRNA expression. The time that the peak expression value of Per1 and CDK1 mRNA appeared (Acrophase) in precancerous lesions was remarkably earlier than that in normal tissues, but the acrophase of p53 and CyclinD1 mRNA expression was remarkably delayed. Moreover, the acrophase of CDK1 and CyclinB1 mRNA expression in cancer tissues was obviously earlier than that in normal tissues, yet there was no significant variation in acrophase of Per1, p53, CyclinD1 mRNA expression between normal tissues and cancer tissues.</p><p><b>CONCLUSIONS</b>The circadian rhythm of clock gene Per1 and cell cycle genes p53, CyclinD1, CDK1, CyclinB1 expression remarkably varied with the occurrence and development of carcinoma. Further research into the interaction between circadian and cell cycle of two cycle activity and relationship with the carcinogenesis may providenew ideas and methods of individual treatment and the mechanism of carcinogenesis.</p>

Circadian variation of clock gene Per2 and cancer-related clock-controlled genes in buccal mucosa carcinoma of golden hamster at different cancer stages / 华西口腔医学杂志

<p><b>OBJECTIVE</b>This study investigates the circadian variation rules of the clock gene Per2 and clock-controlled genes of vascular endothelial growth factor (VEGF), Ki67, c-Myc, and P53 in different stages of carcinogenesis in buccal mucosa carcinoma and their roles in the development of buccal mucosa carcinoma.</p><p><b>METHODS</b>Ninety Syrian golden hamsters were housed under. 12 h light/12 h dark cycles. Dimethylbenzanthracene (DMBA) was used to establish the carcinoma model by smearing the golden hamster buccal mucosa. Before DMBA painting and after 6 and 14 weeks, the hamsters were sacrificed at six time points within a period of 24 h (i.e., 4, 8, 12, 16, 20, and 24 h after light onset), and the normal buccal mucosa, precancerous lesions, and cancer tissues were simultaneously obtained. Hematoxylin and eosin stained sections were prepared to observe the canceration of each tissue. Real time polymerase chain reaction was used to detect the mRNA expression of Per2, VEGF, Ki67, c-Myc, and P53. Cosine analysis was employed to determine the circadian-rhythm variations of Per2, VEGF, Ki67, c-Myc, and P53 mRNA expression in terms of median, amplitude, and acrophase.</p><p><b>RESULTS</b>The expression of Per2, VEGF, P53, and c-Myc mRNA in three different stages appeared with circadian rhythms (P<0.05), whereas the Ki67 mRNA was expressed with circadian rhythm only in normal and precancerous lesion stages (P<0.05). The midline-estimating statistic of rhythms (MESORs) of Per2 and P53 mRNA were significantly down-regulated with the development of cancer (P<0.05), whereas the MESORs of VEGF, c-Myc, and Ki67 mRNA were up-regulated (P<0.05). The amplitude of P53 mRNA significantly decreased with the development of cancer (P<0.05). Moreover, compared with the normal group, the amplitudes of Per2, VEGF, Ki67, and c-Myc mRNA significantly increased in precancerous lesions and cancer tissue (P<0.05). In precancerous stage, the acrophases of Per2, VEGF, and c-Myc mRNA were earlier than that in the normal group, whereas that of Ki67 and P53 mRNA were delayed.</p><p><b>CONCLUSION</b>The circadian-rhythm characteristics of the clock gene Per2 and clock-controlled gene expression of VEGF, Ki67, c-Myc, and P53 mRNA have changed with the occurrence and development of carcinoma.</p>

Evaluation of chemopreventive potentials of ethanolic extract of Ruta graveolens against A375 skin melanoma cells in vitro and induced skin cancer in mice in vivo / 中西医结合学报

<p><b>OBJECTIVE</b>Chemopreventive approach with natural products, particularly plants and plant-derived ones, is receiving increasing attention for their effective role against cancer without any palpable side effects. In this study, efficacy of ethanolic extract of Ruta graveolens (RG) on skin melanoma cells (A375) in vitro and on 7,12-dimethylbenz(a)anthracene (DMBA)-induced skin cancer in vivo has been tested in Swiss albino mice.</p><p><b>METHODS</b>Studies on cell viability, apoptosis and autophagy induction were conducted in vitro. To check apoptosis, assays like alteration in mitochondrial membrane potential, annexin V-fluorescein isothiocyanate/propidium iodide assay and immunoblot were performed. Fluorescence microscopic and immunoblot assays were performed to confirm autophagy induction. The effects of RG were determined by evaluating body weight, tumor incidence, tumor volume and tumor burden in mice. Enzymatic and non-enzymatic antioxidant status was assessed. The role of some relevant signaling proteins was also analyzed.</p><p><b>RESULTS</b>RG caused death of A375 cells through induction of caspase 3-mediated apoptosis and Beclin-1-associated autophagy. Moreover, RG administration (75 mg/kg body weight) which showed no acute or chronic toxicity, showed significant reduction in the skin tumor burden of DMBA-painted mice. RG also demonstrated potent anti-lipid peroxidative and antioxidant functions during the course of skin cancer induction by DMBA.</p><p><b>CONCLUSION</b>Chemopreventive potential of RG was demonstrated from overall results of this study, indicating its possible use in therapeutic formulation of an effective drug to treat skin cancer.</p>

Chemopreventive effect of Brazilian green propolis on experimental dermal carcinogenesis in murine model / Efecto quimiopreventivo del propóleos verde brasileño sobre la carcinogénesis cutánea en el modelo murino experimental

The aim of this study was to assess the effect of oral administration of Hydroalcoholic Extract of Green Propolis (HEGP) on dermal carcinogenesis in rodent model. For the biological assay, we used 36 mice, assigned into 6 groups (n=6): CTR (treated with 100 mg/kg HEGP and no tumor induction), TUM (treated with water and tumor induction), GP10 (treated with 10 mg/kg HEGP and tumor induction), GP50 (treated with 50 mg/kg HEGP and tumor induction) and GP100 (treated with 100 mg/kg HEGP and tumor induction). Cancer induction was performed in the back of the mice by topical application of DMBA. After 16 weeks, mice were euthanized and their backs were submitted to post-mortem histological analysis. The mean number of lesions developed in TUM (4.14±0.89) was significantly higher than in GP10 (2.05±1.02), GP50 (1.8±1.92) and GP100 (2.5±1.73) (p<0.05). The tumors formed in HEGP-treated groups were histologically more differentiated, but only in PV100 in situ lesions were evidenced. Infiltration of anatomical noble structures was less frequent in HEGP-treated groups (p<0.05). Our data suggest that oral administration of HEGP provided partial inhibition of DMBA-induced dermal carcinogenesis, as well as appeared to modulate the differentiation and infiltrative potential of the carcinomas in rodent model.

El objetivo de este estudio fue evaluar el efecto de la administración oral de extracto hidroalcohólico del propóleos verde (HEGP) sobre la carcinogénesis dérmica en modelo de roedores. Para el ensayo biológico, se utilizaron 36 ratones asignados en 6 grupos (n = 6): CTR (tratado con 100 mg/kg HEGP y sin inducción de tumores), TUM (tratada con agua e inducción de tumores), GP10 (tratado con 10 mg/kg HEGP e inducción de tumores), GP50 (tratado con 50 mg/kg HEGP e inducción de tumores) y GP100 (tratado con 100 mg/kg HEGP e inducción de tumores). La inducción de cáncer se llevó a cabo en la región dorsal de los ratones por aplicación tópica de DMBA. Después de 16 semanas, los ratones fueron sacrificados y sus dorsos fueron sometidos a análisis histológico post-mortem. El número medio de lesiones desarrolladas en TUM (4,14±0,89) fue significativamente mayor que GP10 (2,05±1,02), GP50 (1,8±1,92) y gp100 (2,5±1,73) (p<0,05). Los tumores formados en grupos tratados con HEGP fueron histológicamente más diferenciados, pero sólo en PV100 las lesiones in situ fueron manifiestas. La infiltración de las estructuras anatómicas blanco fue menos frecuente en los grupos tratados con HEGP (p<0,05). Nuestros datos sugieren que la administración oral de HEGP proporciona una inhibición parcial de la carcinogénesis dérmica inducida por DMBA, así como pareció modular la diferenciación y potencial infiltrante de los carcinomas en el modelo animal.

Azadirachta indica mitigates DMBA-induced hepatotoxicity: A biochemical and radiometric study.

The hepatoprotective potential of aqueous Azadirachta indica leaf extract (AAILE) was assessed against DMBA-induced hepatotoxicity. DMBA  (7,12-dimethylbenz[a] anthracene) treatment (40 mg/kg body weight, ip) to male Balb/c mice resulted in the derailment of liver function as revealed by extremely slow clearance of 99mTc-mebrofenin from liver, elevated levels of alkaline phosphatase (ALP) and alanine transaminase (ALT), compared to control group. In addition, elevated micronuclei score and high apoptotic index indicated hepatogenotoxicity in DMBA-treated mice. DMBA treatment also upregulated cytochrome P450 (CYP), cytochrome b5 (Cyt b5) and decreased glutathione-S-transferase activity in hepatic tissue, compared to control group. Enhanced lipid peroxidation (LPO) levels along with decreased reduced glutathione (GSH) level were also observed in DMBA group, compared to control group. AAILE co-treatment (200 mg/kg body weight, po, thrice a week) for 8 weeks followed by DMBA injection showed significant improvement in hepatic status, as revealed by normalization of 99mTc-mebrofenin clearance rate, decreased ALP and ALT levels, reduced genotoxicity in terms of micronuclei score and apoptotic index. Levels of LPO were significantly decreased along with increased hepatic GST and GSH levels in AAILE + DMBA group, compared to DMBA group. However, no significant change was observed in hepatic CYP and Cyt b5 levels, compared to DMBA group. The results indicated that AAILE effectively ameliorated DMBA-induced hepatotoxicity.

Establishment of novel rat models for premalignant breast disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Breast cancer has become one of the most common malignant tumors among females over the past several years. Breast carcinogenesis is a continuous process, which is featured by the normal epithelium progressing to premalignant lesions and then to invasive breast cancer (IBC). Targeting premalignant lesions is an effective strategy to prevent breast cancer. The establishment of animal models is critical to study the mechanisms of breast carcinogenesis, which will facilitate research on breast cancer prevention and drug behaviors. In this study, we established a feasible chemically-induced rat model of premalignant breast cancer.</p><p><b>METHODS</b>Following the administration of the drugs (carcinogen, estrogen, and progestogen) to Sprague-Dawley (SD) rats, tumors or suspicious tumors were identified by palpation or ultrasound imaging, and were surgically excised for pathological evaluation. A series of four consecutive steps were carried out in order to determine the carcinogen: 7,12-dimethylbenzaanthracene (DMBA) or 1-methyl-1-nitrosourea, the route of carcinogen administration, the administration period of estrogen and progestogen, and the DMBA dosage.</p><p><b>RESULTS</b>Stable premalignant lesions can be induced in SD rats on administration of DMBA (15 mg/kg, administered three times) followed by administration of female hormones 5-day cycle.</p><p><b>RESULTS</b>were confirmed by ultrasound and palpation.</p><p><b>CONCLUSION</b>Under the premise of drug dose and cycle, DMBA combined with estrogen and progestogen can be used as a SD rat model for breast premalignant lesions.</p>

The Promoting Effect of Carbamide Peroxide Teeth Bleaching Gel in a Preclinical Model of Head and Neck Cancer in Hamster Buccal Pouch

OBJECTIVES: The aim of this study was to verify the promoting effect of carbamide peroxide on dimethylbenzanthracene (DMBA)-induced carcinogenesis in the hamster buccal pouch, in order to reduce the period of latency for tumor formation. METHODS: Sixteen hamsters were randomized into two groups of eight animals each. The hamsters of the group I had their right buccal pouches treated with 0.5% DMBA and 10% carbamide peroxide teeth bleaching gel for 55 days. The animals of the group II had their right pouches treated only with DMBA. After, six animals of each group had their pouches prepared for light microscopy. Histomorphometry was performed to assess the presence of keratinization, nuclear polymorphism, pattern of invasion, number of blood vessels, and inflammatory infiltrate in the tumor front. Furthermore, the newly formed lesions were graded according the Bryne's grading system. The remaining animals had the vascular system of the pouches casted by Mercox and qualitatively analyzed by scanning electron microscopy. RESULTS: Histopathological analysis of the buccal pouches treated with DMBA and carbamide peroxide exhibited formation of squamous cell carcinoma well-differentiated with a high degree of malignancy in all pouches. The development of this neoplasm was associated with a significant increase in the number of blood vessels, presence of keratin pearls, and inflammatory infiltrate. The pouches of the group II showed inflammation, epithelial hyperplasia, dysplasia, and squamous cell carcinoma in only three right pouches. The analysis of the electron micrographs of the pouches chemically inducted with DBMA and carbamide peroxide reveled formation of a new vascular network characteristic of squamous cell carcinoma. CONCLUSION: The protocol presented here, using DMBA associated with carbamide peroxide, shortens the period of latency to produce squamous cell carcinoma in the hamster buccal pouch, decreasing the time and costs of the experiments.

Modulatory effects of Azadirachta indica leaf extract on cutaneous and hepatic biochemical status during promotion phase of DMBA/TPA-induced skin tumorigenesis in mice.

The modulation in biochemical status of skin and hepatic tissue at the time point of commencement of promotion stage of skin carcinogenesis in mice and its intervention with aqueous Azadirachta indica leaf extract (AAILE) were investigated. 7,12-Dimethylbenz(a)anthracene (DMBA, 500 nmol/100 ul of acetone) was applied topically for 2 weeks (twice weekly), followed by phorbol-12-myristate-13-acetate (TPA, 1.7 nmol/100 ul) twice weekly for 6 weeks on the depilated skin of mice and AAILE was administered orally at a dose level of 300 mg/kg body wt thrice a week for 10 weeks. DMBA/TPA treatment upregulated the phase I enzymes in skin and hepatic tissue, as revealed by the increased cytochrome P450 (CYP) and cytochrome b5 (cyt b5) levels and aryl hydrocarbon hydroxylase (AHH) activity when compared to the control group and differentially modulated the activities of phase II enzymes like glutathione-s-transferase (GST), DT-diaphorase (DTD) and uridine diphosphate glucuronosyltransferase (UDP-GT). AAILE treatment decreased the DMBA/TPA-induced increase in cutaneous CYP level and enhanced the DTD and UDP-GT activities when compared with DMBA/TPA group. In the hepatic tissue of AAILE + DMBA/TPA group, an increase in UDP-GT activity was observed when compared to DMBA/TPA group. DMBA/TPA treatment did not alter the skin lipid peroxidation (LPO) level when compared to control group, however, in the animals that received AAILE treatment along with DMBA/TPA, a significant increase in LPO was observed when compared to control group. This was associated with a decrease in cutaneous reduced glutathione (GSH) level of AAILE + DMBA/TPA group. Enhanced LPO level was observed in the hepatic tissue of DMBA/TPA and AAILE + DMBA/TPA groups when compared to control group. However, no alteration was observed in their hepatic GSH levels. The micronuclei score in hepatic tissue did not exhibit significant inter-group differences. The results of the present study suggest that apart from skin, liver may be affected during DMBA/TPA-induced skin tumorigenesis. AAILE treatment has the ability to modulate these changes potentially influencing the process of tumor formation. These findings seem to be important to carcinogenesis and its intervention with anti-cancer agents.

[BRCA1 gene expression in DMBA induced breast cancer in rats]

Breast cancer is one of the most frequent malignancies among women. This study was done to determine the BRCA1 gene expression in 7, 12-Dimethylbenz[a]anthracene [DMBA] induced breast cancer in rats. In this experimental study, the breast cancer was induced by DMBA in Sprague dawley rats. After tumors arise, cell cultures were prepared and G-banding staining was performed on metaphase chromosomal smear. According to databases, genes in the affected area were collected and after comparing genome of the rats and human in changed chromosomal segments, a gene list was prepared. FISH technique was performed on BRCA1 gene to prove accuracy of chromosomal banding results. Structural changes such as deletion occurred in chromosomes 10, which BRCA1 is located on. 24.7% of cells showed evidence of physical deletion in both copy of BRCA1 gene and 23.8% of cells showed deletion in one copy. Induced DMBA Breast cancer cells showed deletion in BRCA1 copy numbers. This gene may be involved in animal breast tumor model

In vitro and in vivo antioxidant potentials of an ethanolic extract of Ganoderma lucidum in rat mammary carcinogenesis / 中国天然药物

AIM@#Considering the importance of diet in the prevention of cellular damage caused by reactive oxygen species which has been implicated for several diseases, this present study was undertaken to evaluate the in vitro and in vivo antioxidant potential of the ethanolic extract of the fruiting bodies of Ganoderma lucidum on 7, 12-dimethylbenz(a)anthracene (DMBA)-induced mammary carcinogenesis in Sprague Dawley rats.@*METHODS@#Ganoderma lucidum extract was tested for in vitro antioxidant and radical scavenging assays, such as (ABTS(+)) radical cation decolorization assay, DPPH radical scavenging, hydroxyl radical, and superoxide radical scavenging assays. The in vivo antioxidant potentials were analyzed by SOD, CAT, and GPx in plasma, mammary, and liver tissues.@*RESULTS@#In all the in vitro antioxidant and radical scavenging assays the extract exhibited good scavenging activity. In vivo enzymatic antioxidant levels, such as SOD, CAT, and GPx were decreased in DMBA-induced animals. Moreover, pretreatment with G. lucidum (500 mg · kg(-1) bw) to DMBA-induced animals significantly (P < 0.05) increased the levels of SOD, CAT, and GPx in plasma, mammary, and liver tissues compared to DMBA induced animals.@*CONCLUSIONS@#From these findings, it is suggested that G. lucidum extract could be considered as a potential source of natural antioxidants and can be used as an effective chemopreventive agent against mammary cancer.

Phytochemical analysis and anticancer capacity of Shemamruthaa, a herbal formulation against DMBA- induced mammary carcinoma in rats

OBJECTIVE@#To investigate the bioactive constituents of Shemamruthaa (SM), a herbal combination and its therapeutic effects on the mitochondrial functions with reference to lipid peroxidation (LPO), antioxidant status, citric acid cycle enzymes and electron transport chain enzymes in mammary tissues of 7,12-dimethylbenz(a)-anthracene (DMBA) induced mammary carcinoma in rat model.@*METHODS@#Adult female Sprague-Dawley rats were used for the study and were divided into four groups. Group I served as control and Group II rats were induced mammary carcinoma by administration of DMBA (25 mg/kg b.w.) orally. The normal and cancer-induced rats (Group III) were treated with SM (400 mg/kg b.w./day) orally by gastric incubation for 14 days. Group IV rats served as SM-treated control animals.@*RESULTS@#Cancer-induced rats showed a considerably increased level of LPO with concomitant decreased levels of antioxidants, citric acid cycle enzymes, electron transport chain enzymes and cytochrome contents in the mammary tissue. Treatment with SM brought back the aforementioned biochemical parameters to near normal.@*CONCLUSIONS@#From the results, it can be inferred that Shemamruthaa possesses significant anticancer effect through its role in attenuation of LPO, prevention of membrane damage and restoring membrane integrity.

Therapeutic effect of ovarian intra-arterial infusion of GE7-delivery system-mediated HSVl-tk/ganciclovir gene therapy in a rat model of malignant ovarian tumor / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To observe the gene expression of herpes simplex virus type 1 thymidine kinase (HSVl-tk) in rat malignant ovarian tumor tissues and the therapeutic effect of ganciclovior (GCV) after intra-arterial infusion of HSVl-tk gene therapy mediated by GE7-delivery system.</p><p><b>METHODS</b>A GE7-polylysine/pCMV-HSV1-tk/polylysine-HA20 4-element complex was constructed. Eighteen rats with DMBA-induced ovarian tumor were divided into 3 groups as Atk, ANS and Vtk groups. The 4-element complex GE7-polylysine/pCMV-HSV1-tk/polylysine-HA20 was injected via the ovarian artery into the rats of Atk group, saline buffer was injected in the ANS groups, and the 4-element complex was injected via the tail vein into the rats of Vtk group. All rats received intraperitoneal injection of GCV in a dose of 50 mg/kg daily for 10 days. The rats were sacrificed 3 days after the final dose of GCV, and the tumor weight was measured and tumor growth inhibition rate was calculated. Flow cytometry was used to assess the cell cycle and apoptosis.</p><p><b>RESULTS</b>The tumor weight in the rats of Atk group was (4.77 ± 2.31) g, significantly lower than that of ANS group [(14.66 ± 6.26) g, P < 0.01] and Vtk group [(17.53 ± 7.19) g, P < 0.01]. The tumor growth inhibition rate of the Atk group was 67.5%, while that of Vtk group was -19.6%. The flow cytometry showed that S-phase tumor cells in the Atk group were (54.32 ± 9.65)%, significantly higher than that in the ANS (27.43 ± 9.22)% and (30.16 ± 11.57)% in the Vtk group (both P < 0.01). The tumor cell apoptosis rate in the Atk group was (39.15 ± 12.16)%, significantly higher than that in the ANS group [(11.86 ± 5.28)%, P < 0.01] and Vtk group [(14.32 ± 6.43)%, P < 0.01].</p><p><b>CONCLUSION</b>HSV1-tk/GCV gene therapy system mediated by GE7 non-viral delivery system via ovarian arterial infusion effectively causes cell cycle arrest at S phase and enhances cell apoptosis, therefore, exerts an inhibitory effect on tumor growth.</p>