Inactivation of the Tumor Suppressor CYLD Sensitizes Mice to Breast Cancer Development.

BACKGROUND/AIM: Breast cancer is a leading cause of cancer-related deaths among women. Down-regulation of the tumor suppressor gene Cyld in breast cancer has been linked to a poor prognosis. This study investigated the role of Cyld in breast cancer using conditional mutant mouse models carrying a Cyld mutation, which inactivates the deubiquitinating activity of its protein product CYLD in mammary epithelial cells. MATERIALS AND METHODS: We examined the potential of CYLD inactivation to induce mammary tumors spontaneously or modify the susceptibility of mice to mammary tumorigenesis by DMBA treatment or ErbB2 over-expression. RESULTS: CYLD inactivation significantly increased susceptibility to breast cancer induced by either DMBA treatment or ErbB2 over-expression. Moreover, while CYLD inactivation alone did not lead to spontaneous mammary tumorigenesis, it did contribute to the formation of multifocal hyperplastic lesions in virgin mice of predominantly FVB/NJ background. CONCLUSION: Our study demonstrates the tumor enhancing potential of CYLD inactivation in mammary tumorigenesis in vivo and establishes novel relevant mouse models that can be exploited for developing prognostic and therapeutic protocols.

Sunset Yellow protects against oxidative damage and exhibits chemoprevention in chemically induced skin cancer model.

Skin cancer and other skin-related inflammatory pathologies are rising due to heightened exposure to environmental pollutants and carcinogens. In this context, natural products and repurposed compounds hold promise as novel therapeutic and preventive agents. Strengthening the skin's antioxidant defense mechanisms is pivotal in neutralizing reactive oxygen species (ROS) and mitigating oxidative stress. Sunset Yellow (SY) exhibits immunomodulatory characteristics, evidenced by its capacity to partially inhibit the secretion of proinflammatory cytokines, regulate immune cell populations, and modulate the activation of lymphocytes. This study aimed to investigate the antioxidant and anti-genotoxic properties of SY using in-silico, in vitro, and physiochemical test systems, and to further explore its potential role in 7,12-dimethylbenz(a) anthracene (DMBA)/ 12-o-tetradecanoylphorbol-13-acetate (TPA)-induced two-stage skin carcinogenesis. In vitro experiments showed that pre-treatment of SY significantly enhanced the cell viability of HaCaT cells when exposed to tertiary-Butyl Hydrogen Peroxide (tBHP). This increase was accompanied by reduced ROS levels, restoration of mitochondrial membrane potential, and notable reduction in DNA damage in (SY + tBHP) treated cells. Mechanistic investigations using DPPH chemical antioxidant activity test and potentiometric titrations confirmed SY's antioxidant properties, with a standard reduction potential ( E o ) of 0.211 V. Remarkably, evaluating the effect of topical application of SY in DMBA/TPA-induced two-step skin carcinogenesis model revealed dose-dependent decreases in tumor latency, incidence, yield, and burden over 21-weeks. Furthermore, computational analysis and experimental validations identified GSK3ß, KEAP1 and EGFR as putative molecular targets of SY. Collectively, our findings reveal that SY enhances cellular antioxidant defenses, exhibits anti-genotoxic effects, and functions as a promising chemopreventive agent.

[Effect and mechanism of Yueju Pills on breast cancer induced by DMBA in rats].

This paper aims to explore the inhibitory effect of Yueju Pills on breast cancer and decipher the underlying mechanism. A total of 92 SPF-grade SD female rats were involved in this study, and 14 of them were randomly selected into control group. The remaining 78 rats were administrated with 7,12-dimethylbenzanthracene(DMBA) by gavage to establish the breast cancer model. The modeled rats were randomized into model, tamoxifen(1.9 mg·kg~(-1)·d~(-1)), and low-and high-dose(17, 34 g·kg~(-1)·d~(-1)) Yueju Pills groups. The mental state, food intake, and activities of the rats were observed daily, and the body weight was measured on alternate days. After 12 weeks of administration, the rats were sacrificed and the tumor weight was measured. The serum estrogen and progeste-rone levels were determined by enzyme-linked immunosorbent assay. The histopathological changes of the breast and tumor were observed by hematoxylin-eosin staining. Western blot was employed to measure the protein levels of glucose transporter 1(GLUT1), lactate dehydrogenase A(LDHA), phosphofructokinase muscle(PFKM), pyruvate kinase isozyme type M2(PKM2), hexokinase 2(HK2), nuclear factor-kappaB(NF-κB), and phosphorylated NF-κB. The intestinal microbiome was examined by 16S rRNA high-throughput sequencing. The results showed that compared with the model group, high and low-dose Yueju Pills showed the tumor inhibition rate of 15.8% and 64.5%, respectively, and the low dose group had stronger inhibitory effect. Compared with the control group, the model group presented elevated the levels of estrogen and progesterone in serum. The administration of Yueju Pills lowered such ele-vation, and the low-dose group showed stronger lowering effect(P<0.05). Compared with the model group, Yueju Pills reduced the glands with increased breast tissue, the degree of breast duct expansion, the number and area of acinar cavity, the secretions, and the layers of mammary epithelial cells. Furthermore, Yueju Pills down-regulated the expression of GLUT1, LDHA, PFKM, PKM2, HK2, and NF-κB(P<0.05) and altered the diversity, composition, structure, and abundance of intestinal flora. The results showed that Yueju Pills could inhibit breast cancer by regulating the secretion of estrogen and progesterone, glycolysis, inflammatory cytokines, and intestinal flora.

In Vitro and In Vivo Preventive Effects of Thymoquinone against Breast Cancer: Role of DNMT1.

Breast cancer (BC) is one of the most common cancers in women and is a major cause of female cancer-related deaths. BC is a multifactorial disease caused by the dysregulation of many genes, raising the need to find novel drugs that function by targeting several signaling pathways. The antitumoral drug thymoquinone (TQ), found in black seed oil, has multitargeting properties against several signaling pathways. This study evaluated the inhibitory effects of TQ on the MCF7 and T47D human breast cancer cell lines and its antitumor activity against BC induced by a single oral dose (65 mg/kg) of 7,12-dimethylbenzanthracene (DMBA) in female rats. The therapeutic activity was evaluated in DMBA-treated rats who received oral TQ (50 mg/kg) three times weekly. TQ-treated MCF7 and T47D cells showed concentration-dependent inhibition of cell proliferation and induction of apoptosis. TQ also decreased the expression of DNA methyltransferase 1 (DNMT1) in both cancer cell types. In DMBA-treated animals, TQ inhibited the number of liver and kidney metastases. These effects were associated with a reduction in DNMT1 mRNA expression. These results indicate that TQ has protective effects against breast carcinogens through epigenetic mechanisms involving DNMT1 inhibition.

Usnic acid attenuates 7,12-dimethylbenz[a] anthracene (DMBA) induced oral carcinogenesis through inhibiting oxidative stress, inflammation, and cell proliferation in male golden Syrian hamster model.

In this study, we investigated the chemopreventive efficacy of usnic acid (UA), an effective secondary metabolite component of lichens, against 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral squamous cell carcinoma (OSCC) in the hamster model. Initially, the buccal pouch carcinogenesis was induced by administering 0.5% DMBA to the HBP (hamster buccal pouch) region about three times a week until the 10th week. Then, UA was orally treated with different concentrations (25, 50, 100 mg/kg b.wt) on alternative days of DMBA exposure, and the experimental process ended in the 16th week. After animal experimentation, we observed 100% tumor incidence with well-differentiated OSCC, dysplasia, and hyperplasia lesions in the DMBA-induced HBP region. Furthermore, the UA treatment of DMBA-induced hamster effectively inhibited tumor growth. In addition, UA upregulated antioxidant levels, interfered with the elevated lipid peroxidation by-product of thiobarbituric acid reactive substances, and changed the activities of the liver detoxification enzyme (Phase I and II) in DMBA-induced hamsters. Furthermore, immunohistochemical staining of inflammatory markers (iNOS and COX-2) and proliferative cell markers (cyclin-D1 and PCNA) were upregulated in the buccal pouch part of hamster animals induced with DMBA. Notably, the oral administration of UA significantly suppressed these markers during DMBA-induced hamsters. Collectively, our findings revealed that UA exhibits antioxidant, anti-inflammatory, antitumor, and apoptosis-inducing characteristics, demonstrating UA's protective properties against DMBA-induced HBP carcinogenesis.

The potential protective and therapeutic effects of cannabidiol oil on experimental Leukemia induced by DMBA in male rats.

BACKGROUND: 7,12-Dimethylbenzanthracene (DMBA) is a member of the polycyclic aromatic hydrocarbon family. It is a member of the polycyclic aromatic hydrocarbon family. It is a mutagenic, carcinogenic, and immunosuppressor agent. Cannabidiol (CBD) is a phytocannabinoid. It has anticonvulsant, anti-inflammatory, anti-anxiety, antioxidant, and anti-cancer properties. The purpose of this study was to investigate the possible protective and therapeutic benefits of CBD oil in DMBA-induced leukemia in rats. METHOD: Experimental animals were divided into six groups of five rats each. Group 1 (normal control) included healthy rats. Group 2 included normal rats that received olive oil. Group 3 included normal rats that received CBD. Group 4 included the DMBA-induced leukemic group. Group 5 (prophylactic group) included rats that received CBD as a prophylaxis before IV injection with DMBA. Group 6 (treated group) included DMBA-induced leukemic rats that received CBD as treatment. Liver functions (total, direct and indirect bilirubin, alkaline phosphatase (ALP), alanine transaminase (ALT), aspartate aminotransferase (AST), albumin, globulin, and albumin globulin ratio) were measured. Superoxide dismutase (SOD) and catalase (CAT) were also measured. Total RNA extraction followed by-real time qRT-PCR gene expression of LC3-II, Beclin, mTOR, and P62 was performed. Histopathological examination of liver and spleen tissues was performed. RESULTS: Administration of CBD in groups 5 and 6 resulted in a significant improvement of the levels of liver functions compared to the leukemic untreated rats. Also, the levels of catalase and SOD significantly increased after treatment with CBD compared to the leukemic group. After treatment with CBD in groups 5 and 6, there were downregulations in the expression of all studied genes compared to leukemic untreated rats. Treatment with CBD was more statistically effective than prophylactic use. CONCLUSION: Administration of CBD resulted in a significant improvement in the biochemical, antioxidant status, morphological, and molecular measures in DMBA-induced leukemia in adult male rats. The therapeutic use was more effective than the prophylactic one.

miRNA-214-3p stimulates carcinogen-induced mammary epithelial cell apoptosis in mammary cancer-resistant species.

Mammary cancer incidence varies greatly across species and underlying mechanisms remain elusive. We previously showed that mammosphere-derived epithelial cells from species with low mammary cancer incidence, such as horses, respond to carcinogen 7, 12-Dimethylbenz(a)anthracene-induced DNA damage by undergoing apoptosis, a postulated anti-cancer mechanism. Additionally, we found that miR-214-3p expression in mammosphere-derived epithelial cells is lower in mammary cancer-resistant as compared to mammary cancer-susceptible species. Here we show that increasing miR-214 expression and decreasing expression of its target gene nuclear factor kappa B subunit 1 in mammosphere-derived epithelial cells from horses abolishes 7,12-Dimethylbenz(a)anthracene-induced apoptosis. A direct interaction of miR-214-3p with another target gene, unc-5 netrin receptor A, is also demonstrated. We propose that relatively low levels of miR-214 in mammosphere-derived epithelial cells from mammals with low mammary cancer incidence, allow for constitutive gene nuclear factor kappa B subunit 1 expression and apoptosis in response to 7, 12-Dimethylbenz(a)anthracene. Better understanding of the mechanisms regulating cellular responses to carcinogens improves our overall understanding of mammary cancer resistance mechanisms.

Potential chemopreventive effects of Broccoli extract supplementation against 7, 12 dimethyl Benz(a)anthracene (DMBA) -induced toxicity in female rats.

Dietary components have recently received rapidly expanding attention for their potential to halt or reverse the development of many oxidative stress-mediated diseases after exposure to environmental toxicants. 7, 12 dimethylbenz(a)anthracene (DMBA) is one of the most common environmental pollutants. The present study aimed to evaluate the chemo-preventive effects of broccoli as a nutritional component against DMBA intoxication in rats. A daily dose of aqueous (1 ml/rat) and methanolic (150 mg/kg) broccoli extracts, respectively, was given to 50-day-old female rats for 26 successive weeks after carcinogen intoxication with a single dose of 20 mg/ml of DMBA. DMBA intoxication resulted in a redox imbalance (a decreased GSH level and an increased MDA level) and increased DNA fragmentation in the liver, kidney, and brain. Besides, it affected the level of expression of the bcl2 gene in the liver, kidney, and brain tissue but didn't affect cfos gene expression accompanied by histopathological changes. The aqueous and methanolic broccoli extract supplements ameliorated the adverse effects by increasing the level of GSH, decreasing the MDA level, and reducing DNA fragmentation. Besides, broccoli extracts decreased the expression of bcl2 in the liver and brain and up-regulated bcl2 expression in the kidney, accompanied by lowering NF-κß 65 expression in the liver and brain and γ-catenin expression in the liver and kidney. In conclusion, broccoli as a dietary component had a strong chemoprotective effect against oxidative stress, DNA damage, and genotoxicity induced by DMBA intoxication in rats.

Fullerene C60 reduces acute lung injury by suppressing oxidative stress-mediated DMBA-induced apoptosis and autophagy by regulation of cytochrome-C/caspase-3/beclin-1/IL-1α/HO-1/p53 signaling pathways in rats.

The objective of this study was to evaluate the effect of fullerene C60 nanoparticles against 7,12-dimethylbenz[a]anthracene (DMBA)-induced lung tissue damage in rats. 60 Wistar albino (8 weeks old) female rats were assigned into four groups: Control Group (C), Fullerene C60, DMBA, and Fullerene C60+DMBA. The rats in the DMBA and Fullerene C60+DMBA groups were administered DMBA (45 mg/kg bw, oral gavage). The rats in Fullerene C60, and Fullerene C60+DMBA groups were administered with Fullerene C60 (1.7 mg/kg bw, oral gavage). Expression levels of cytochrome-C, caspase-3, beclin-1, IL-1α, HO-1 and p53 proteins in lung tissue were determined by western blotting, lipid peroxidation malondialdehyde (MDA) analyzes, glutathione (GSH), glutathione peroxidase (GSH-Px), catalase activity (CAT) and total protein levels were determined by spectrophotometer. In addition, lung tissues were evaluated by histopathologically. Fullerene C60 reduced the increasing of MDA and IL-1α protein expression levels and attenuated histopathological changes in lung. Moreover, fullerene C60 enhanced the protein expression of cytochrome-C, caspase-3, beclin-1, HO-1, and p53, which were decreased in the DMBA group. Fullerene C60 has strong biological activity that it might be an effective approach for lung damage.

[Effect and mechanism of Xihuang Pills on rats with precancerous lesions of breast].

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.

Allyl isothiocyanate inhibits invasion and angiogenesis in breast cancer via EGFR-mediated JAK-1/STAT-3 signaling pathway.

Angiogenesis, invasion, and metastasis are the main events of cancer cells. JAK-1/STAT-3 is a key intracellular signaling transduction pathway, which controls the growth, differentiation, apoptosis, invasion, and angiogenesis of various cancer cells. The present study explored the impact of allyl isothiocyanate (AITC) on the JAK-1/STAT-3 pathway in DMBA-induced rat mammary tumorigenesis. The mammary tumor was initiated through a single dose of 25 mg DMBA/rat by a subcutaneous injection administered near the mammary gland. We observed decreased body weight and increased the total number of tumors, tumor incidence, tumor volume, well-developed tumor, and histopathological abnormalities in DMBA-induced rats that were modulated after being treated with AITC. Staining of mammary tissues showed a high accumulation of collagen in DMBA-induced rats and it was normalized by the AITC treatment. Moreover, DMBA-induced mammary tissues showed up-regulated expressions of EGFR, pJAK-1, pSTAT-3, nuclear fraction of STAT-3, VEGF, VEGFR2, HIF-1α, MMP-2, and MMP-9 and the down-regulated expressions of cytosolic fraction of STAT-3 and TIMP-2. Oral administration of AITC on DMBA-induced rats inhibits angiogenesis and invasion by modifying these angiogenic and invasive markers. The finding of the present study was further confirmed by molecular docking analysis that shows a strong binding interaction between AITC with STAT-3 and cocrystal structure of STAT-3 glide energy of -18.123 and -72.246 (kcal/mole), respectively. Overall, the results suggested that AITC inhibits activation of the JAK-1/STAT-3 pathway, which subsequently prevents angiogenesis and invasion. It was recommended that AITC might develop a beneficial effect against breast cancer.

C-type natriuretic peptide (CNP) inhibits 7,12-Dimethylbenz[a]anthracene (DMBA)/Croton oil-induced skin tumor growth by modulating inflammation in Swiss albino mice.

C-type natriuretic peptide (CNP) exhibits anti-inflammatory activity besides its natriuretic and diuretic functions. The present study aimed to determine the anticancer and synergistic therapeutic activity of CNP against a 7,12-Dimethylbenz[a]anthracene (DMBA)/Croton oil-induced skin tumor mouse model. CNP (2.5 µg/kg body weight) was injected either alone and/or in combination with Cisplatin (CDDP) (2 mg/kg body weight) for 4 weeks. The dorsal skin tumor incidences/growth and mortality rate were recorded during the experimental period of 16 weeks. The serum C-reactive protein (CRP), and lactate dehydrogenase (LDH) levels, infiltrating mast cells, and AgNORs proliferating cells count were analyzed in control and experimental mice. Further, the expression profile of marker genes of proliferation, inflammation, and progression molecules were analyzed using Reverse transcriptase-polymerase chain reaction (RT-PCR)/quantitative PCR (qPCR), western blot, and immunohistochemistry. The DMBA/Croton oil-induced mice exhibited 100% tumor incidence. Whereas, CNP alone, CDDP alone, and CNP+CDDP combination-treated mice exhibited 58%, 46%, and 24% tumor incidence, respectively. Also, a marked reduction in the levels of serum CRP and LDH, the number of infiltrating mast cells count and AgNORs proliferating cells count were noticed in the mice skin sections. Further, a significant reduction in both mRNA and protein expression levels of proliferation, inflammation, and progression markers were noticed in CNP (p < 0.01), CDDP (p < 0.01), and CNP+CDDP combination (p < 0.001) treated mice, respectively. The results of the present study suggest that CNP has anticancer activity. Further, the CNP+CDDP treatment has more promising anticancer activity as compared with CNP or CDDP alone treatment, probably due to the synergistic antiproliferative and anti-inflammatory activities of CNP and CDDP.

Ursolic acid-loaded chitosan nanoparticles suppress 7,12-dimethylbenz(a)anthracene-induced oral tumor formation through their antilipid peroxidative potential in golden Syrian hamsters.

Oral cancer, a disfiguring and life threatening cancer, significantly affects the day-to-day life of not only the patients but also their family members in terms of life quality and financial burden. India records higher incidence of oral cancer every year and is mainly due to the habituation of tobacco products and alcohol abuse. Delay in diagnosis and treatment influences India's higher incidence of oral cancer, where annually 50,000-60,000 oral carcinoma cases are reported. 7,12-dimethylbenz(a)anthracene (DMBA)-induced cancer in the oral cavity mimics human oral cancer in histopathological, molecular, and morphological aspects, and thus, by using this paradigm, the tumor inhibiting efficacy of medicinal plants or herbs and their components is scientifically validated. Ursolic acid, due to its multiple pharmacological effects, has been attracted, in recent years, for chemoprevention research program. Though, ursolic acid has been shown to have beneficial effects, its poor water solubility and bioavailability hinder to exert its 100% efficacy. Therefore, ursolic acid is encapsulated in either natural or synthetic polymers to enhance its therapeutic efficacy. Chitosan is one of the natural polymers that have been employed in the synthesis of nanoparticles to improve the drug efficacy. The present study has thus chosen ursolic acid-loaded chitosan nanoparticles (UACNP) to assess its anticancer efficacy in the DMBA-induced oral carcinoma. The anticancer efficacy of UACNP in experimental oral carcinogenesis was assessed by employing the status of oxidative markers and detoxification cascade as an end point. DMBA-induced abnormalities in the status of oxidative markers and detoxification cascade were reversed by ursolic acid-loaded chitosan nanoparticles. The tumor inhibiting or suppressing effect of UACNP is thus explored in experimental oral carcinogenesis.

The Anti-Tumorigenic Role of Cannabinoid Receptor 2 in Non-Melanoma Skin Cancer.

Five million non-melanoma skin cancers occur globally each year, and it is one of the most common malignant cancers. The dysregulation of the endocannabinoid system, particularly cannabinoid receptor 2 (CB2), is implicated in skin cancer development, progression, and metastasis. Comparing wildtype (WT) to systemic CB2 knockout (CB2-/-) mice, we performed a spontaneous cancer study in one-year old mice, and subsequently used the multi-stage chemical carcinogenesis model, wherein cancer is initiated by 7,12-dimethylbenz[a]anthracene (DMBA) and promoted by 12-O-tetradecanoylphorbol-13-acetate (TPA). We found that aging CB2-/- mice have an increased incidence of spontaneous cancerous and precancerous skin lesions compared to their WT counterparts. In the DMBA/TPA model, CB2-/- developed more and larger papillomas, had decreased spontaneous regression of papillomas, and displayed an altered systemic immune profile, including upregulated CD4+ T cells and dendritic cells, compared to WT mice. Immune cell infiltration in the tumor microenvironment was generally low for both genotypes, although a trend of higher myeloid-derived suppressor cells was observed in the CB2-/- mice. CB2 expression in carcinogen-exposed skin was significantly higher compared to naïve skin in WT mice, suggesting a role of CB2 on keratinocytes. Taken together, our data show that endogenous CB2 activation plays an anti-tumorigenic role in non-melanoma skin carcinogenesis, potentially via an immune-mediated response involving the alteration of T cells and myeloid cells coupled with the modulation of keratinocyte activity.

Anticancer role of mango (Mangifera indica L.) peel and seed kernel extracts against 7,12- dimethylbenz[a]anthracene-induced mammary carcinogenesis in female rats.

Breast cancer is the second leading cause of cancer death among women. The present study is an effort to reveal the antiproliferative and antioxidant actions of mango seed kernel extract (KE), peel extract (PE), and their combination (KEPE) on mammary tumors induced by 7,12 dimethylbenz[a]anthracene (DMBA). Seven groups of adult female Sprague-Dawley rats were prepared, including C: (control), DMBA: (rats were administered with DMBA), (DMBA-KE), (DMBA-PE), and (DMBA-KEPE): rats were administered with DMBA and then treated with KE, PE, and (both KE and PE), respectively, (KE) and (PE): rats were administered with KE and PE, separately. The study focused on the assessment of markers of endocrine derangement [serum 17-ß estradiol (E2)], apoptosis [caspase-3 and deoxyribonucleic acid fragmentation (DNAF)], and oxidative stress [lipid peroxidation and antioxidants (glutathione, glutathione-S-transferase, glutathione reductase, glutathione peroxidase, and superoxide dismutase)]. Histopathological examination and immunohistochemical expression of caspase-3 and estrogen receptor-α (ER-α) in mammary gland tissues (MGTs) were determined, as well as the characterization of mango extracts. The results showed that DMBA administration induced mammary tumors by increasing cell proliferation and evading apoptosis. In addition, DMBA administration caused oxidative stress by the production of reactive oxygen species, which increased lipid peroxidation and decreased cellular antioxidants, allowing cancer to progress. In contrast, treatment with DMBA-KE, DMBA-PE, or DMBA-KEPE diminished mammary tumors induced by DMBA, where they reduced oxidative stress via increased antioxidant parameters including reduced glutathione, superoxide dismutase, total glutathione peroxidase, glutathione reductase, and glutathione S-transferase. Also, different treatments decreased proliferation through the reduction of E2, and ER-α expression levels. However, these treatments increased the apoptosis of unwanted cells as they increased caspase-3 activity and DNAF. All these changes led to the prevention of breast injuries and the reduction of mammary tumors. This demonstrates that the contents of mango extracts, especially phenolics and flavonoids, have an important role in mammary tumor treatment through their potential antioxidant, antiproliferative, proapoptotic, and anti-estrogenic effects. KE and PE administration for 4 weeks had no adverse effects. Conclusion: Each of KE, PE, and KEPE has a therapeutic effect against DMBA-induced mammary tumors via induction of apoptosis and reduction of each of the OS, proliferation, and estrogenic effects. So, they can play an important role in the pharmacological tole.

Protective Effects of Pelargonidin against DMBA-Induced Mammary Tumorigenesis in BALB/c Mice through Reduced Oxidative Stress and Lipid Anomalies.

Among luminal types of breast cancers, ER + breast cancer is the most frequently diagnosed cancer globally. ER + breast cancer is commonly treated with SERM drugs that block ER to prevent ER-mediated cancerous growth. Our previous computational screening found pelargonidin (PG) can inhibit ER-signaling with potent bioactivity and satisfactory toxicological features. The present study explored the anti-tumoral prospect of PG against DMBA-induced ER + murine mammary carcinogenesis. The female BALB/c mice were divided into control (A) and DMBA-exposed groups. Following tumor appearance, the DMBA-exposed group was divided into five groups: tumor control, PG-treated (Groups P25, P50, and P100), and tamoxifen-treated (TAM). The results indicated that PG-treatment dose-dependently reduced the mean tumor volume, reinstated body weight loss, and enhanced the percentage survival of tumor-bearing mice. In addition, we recorded a significant reduction in LPO, total cholesterol, and triglycerides and a surge in the activity of antioxidases and phase II detoxifying enzymes in PG-treated animals. PG also dose-dependently increased the serum level of unbound estradiol, an indicator of competitive ER binding by an ER agonist/antagonist. These data suggest that pelargonidin has potent anticancer potential against the animal model of ER + breast cancer that matches the efficiency of tamoxifen with conceivably fewer side effects.

Tenofovir alone or combined with doxorubicin abrogates DMBA-induced mammary cell carcinoma: An insight into its modulatory impact on oxidative/Notch/apoptotic signaling.

AIMS: Breast cancer incidence keeps on growing and emerging as one of the major global challenges, therefore, the introduction of new approaches is of great demand. Drug repurposing is crucial to faster and cheaper discovery of anti-cancer drugs. The antiviral tenofovir disproxil fumarate (TF) was reported to decrease hepatocellular carcinoma risk by interfering with cell cycle and proliferation. This study aimed to scrutinize the role of TF alone or combined with doxorubicin (DOX) in 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast carcinoma rat model. MATERIALS AND METHODS: Breast carcinoma was induced by DMBA (7.5 mg/kg, twice/week, subcutaneous into mammary gland) for 4 successive weeks. TF (25 and 50 mg/kg/day) was given orally and DOX (2 mg/kg) was injected once/week by tail vein starting from day 1. KEY FINDINGS: The anti-cancerous effect of TF was mediated by suppression of oxidative stress markers and Notch signaling proteins (Notch1, JAG1, and HES1), attenuation of tumor proliferation markers (cyclin-D1 and Ki67), and boosting of apoptosis (P53 and Caspase3) and autophagy biomarkers (Beclin1 and LC3). In parallel, histopathological assessment displayed that mammary glands from animals treated with TF alone or combined with DOX showed better histopathological scores. Interestingly, TF and DOX co-treatment markedly decreased myocardial injury markers (AST, LDH, and CK-MB), restored the balance between GSH and ROS, prohibited lipid peroxidation, and preserved microscopic myocardial architecture. SIGNIFICANCE: TF elicited antitumor activity via multiple molecular mechanisms. Moreover, combining TF with DOX might be a potential novel strategy to enhance DOX-anticancer activity and decrease its cardiac side effects.

Breast cancer cell growth arrest and chemopreventive effects of Passiflora edulis Sims (Passifloraceae) ethanolic leaves extract on a rat model of mammary carcinoma.

ETHNOPHARMACOLOGICAL RELEVANCE: Despite various prevention and treatment measures, the incidence and mortality due to breast cancer has been increasing globally. Passiflora edulis Sims is a plant used for the treatment of various diseases in traditional medicine, including cancers. AIM OF THE STUDY: To assess the anti-breast cancer activity of the ethanolic extract of P. edulis leaves in vitro and in vivo. MATERIAL AND METHODS: In vitro, the cell growth and proliferation were determined based on the MTT and BrdU assays. The flow cytometry was used to analyze the cell death mechanism while, cell migration, cell adhesion and chemotaxis were assayed for anti-metastatic potential. In vivo, 56 female Wistar rats aged 45-50 days (∼75 g) were exposed to 7,12-dimethylbenz(a)anthracene-DMBA except the normal group. Negative control group (DMBA) received solvent dilution throughout the study; standards groups (tamoxifen - 3.3 mg/kg BW and letrozole - 1 mg/kg BW) as well as P. edulis leaves ethanolic extract groups (50, 100 and 200 mg/kg) treated for 20 weeks. Tumor incidence, tumor burden and volume, CA 15-3 serum' level, antioxidant, inflammatory status and histopathology were assessed. RESULTS: P. edulis extract showed a significant and concentration-dependent inhibition of MCF-7 and MDA-MB 231 cells growth at 100 µg/mL. It inhibited cell proliferation and clones' formation and induced apoptosis in MDA-MB 231 cells. The migration of cell into the zone freed of cells and the number of invading cells after the 48 and 72 h were significantly diminished while, it increased their adherence to collagen and fibronectin extracellular matrix as does Doxorubicin. In vivo, all rats in the DMBA group exhibited a significant (p < 0.001) increase in tumor volume, tumor burden and grade (adenocarcinoma of SBR III) and pro-inflammatory cytokine levels (TNF-α, INF-γ, IL-6 and IL-12). P. edulis extract at all tested doses significantly inhibited the DMBA-induced increase in tumor incidence, tumor burden and grade (SBR I) as well as pro-inflammatory cytokines. Moreover, it increased enzymatic and non-enzymatic antioxidants (SOD, catalase, and GSH) and decreased MDA levels although a greater effect was observed with Tamoxifen and Letrozole. P. edulis has medium content on polyphenols, flavonoids and tannins. CONCLUSION: P. edulis has chemo-preventive effects against DMBA-induced breast cancer in rats probably through its antioxidative, anti-inflammatory and apoptosis-inducing potentials.