Rat Mammary Carcinoma Research Articles

Crocetin regulates cell cycle progression in N-nitroso-Nmethylurea(NMU)-induced breast cancer in rat: cyclin D1 suppression, p21Cip1 and p53 induction

Objectives: Crocetin, a saffron-derived carotenoid, inhibits tumor growth in some cancer types. However, its mechanism of action still needs to be clearly understood. Here, the Crocetin effect on the expression of some cell cycle regulators was investigated. Methods: The N-nitroso-N-methylurea (NMU)-induced rat mammary carcinomas were induced in a group of 35-day-old female Wistar Albino rats. Then, the expression of several cell cycle regulators was studied using reverse transcription-polymerase chain reaction (RT-PCR) and Western blot. After the tumor appearance, these rats were treated with Crocetin through weekly, intraperitoneal injections of 100 mg/kg body weight for four weeks. A control group has received the vehicle only. In the end, rats were sacrificed, and tumors were divided into two parts. A part was for pathologic investigation, and a part was retained at -70 °C to determine desired parameters. Results: Before Crocetin treatment, the tumor volumes were 13.27 ± 3.77 and 9.44 ± 4.39 cm3 , which was changed to 23.66 ± 8.82 and 4.71 ± 2.44 cm3 at the end of the experiment in the untreated and treated groups, respectively. The results showed that Crocetin markedly decreased the increased expression of cyclin D1 due to NMU administration. However, it further increased the expression of p53 and p21Cip1, with no significant effect on p27Kip1 expression. We previously showed Crocin-induced cell cycle arrest through a p53-dependent mechanism. Conclusion: Crocetin induced the cell cycle arrest in NMU-induced breast cancer in rats through a p53-independent mechanism. It is the second mechanism additional to apoptosis induction in cancer cells.

Catechin enhances the antitumour activity of Bleomycin in DMBA-induced mammary carcinoma in rats

Catechin enhances the antitumour activity of Bleomycin in DMBA-induced mammary carcinoma in rats

Anticancer effects of pH- sensitive carvacrol zinc oxide quantum dots on DMBA induced mammary carcinoma in female sprague dawley rats

ObjectivesThe current research explores the anticancer effects of pH sensitive CVC-ZnO QDs (Carvacrol-loaded Zinc Oxide Quantum Dots) on DMBA induced mammary carcinoma in rats. MethodsFemale SD rats were used, and mammary cancer was induced by chemical carcinogen via subcutaneous injection near the mammary gland. Different concentrations of CVC-ZnO QDs were orally supplemented to evaluate the optimum dose. We assessed the growth rate, body weight changes, tumor volume, tumor incidence and tumor burden in both the inducer and treatment groups. We also evaluated the biochemical parameters (antioxidant status, lipid peroxidation, detoxification enzymes, and lipid profile) and histopathological changes in the kidney and mammary tissues. ResultsOur findings indicate that CVC-ZnO QDs treated rats significantly decreased the tumor weight, incidence, burden, lipid peroxidation levels, phase I detoxification enzyme activities and increased the body weight, phase II detoxification enzyme activities, and antioxidant status compared to the DMBA alone treated rats. CVC-ZnO QDs treatment also altered the lipid profile of plasma and mammary tissue. Furthermore, histopathological results confirmed that the CVC-ZnO QDs protect against DMBA-mediated damage to the mammary and kidney. ConclusionThe findings indicate that the CVC-ZnO QDs administered at 4 mg/kg b.w exhibited a significant anticancer effect against DMBA-induced mammary cancer.

Vitex Berries Attenuates Chemically-Induced Mammary Carcinomas in Rats through modulation of the cancer growth rate-limiting enzymes activities: aromatase and Na+/K+ ATPase.

Vitex Berries Attenuates Chemically-Induced Mammary Carcinomas in Rats through modulation of the cancer growth rate-limiting enzymes activities: aromatase and Na+/K+ ATPase.

Classification of rat mammary carcinoma with large scale in vivo microwave measurements

Mammary carcinoma, breast cancer, is the most commonly diagnosed cancer type among women. Therefore, potential new technologies for the diagnosis and treatment of the disease are being investigated. One promising technique is microwave applications designed to exploit the inherent dielectric property discrepancy between the malignant and normal tissues. In theory, the anomalies can be characterized by simply measuring the dielectric properties. However, the current measurement technique is error-prone and a single measurement is not accurate enough to detect anomalies with high confidence. This work proposes to classify the rat mammary carcinoma, based on collected large-scale in vivo S_{11} measurements and corresponding tissue dielectric properties with a circular diffraction antenna. The tissues were classified with high accuracy in a reproducible way by leveraging a learning-based linear classifier. Moreover, the most discriminative S_{11} measurement was identified, and to our surprise, using the discriminative measurement along with a linear classifier an 86.92% accuracy was achieved. These findings suggest that a narrow band microwave circuitry can support the antenna enabling a low-cost automated microwave diagnostic system.

Diosgenin Nanoparticles Competes Plain Diosgenin on Reviving Biochemical and Histopathological Alterations in DMBA Induced Rat Mammary Carcinoma via Modulating the AhR-Nrf-2 Signaling Cascades

Background: Diosgenin, a steroidal saponin spotted as a primary ingredient in many traditional Chinese medicines, has sparked the attention of researchers owing to its multi-targeted cytotoxicity towards a multitude of cancers. Regrettably, its true potential was bounded by its impoverished physicochemical properties. In order to fully exploit its ability, we plan to fabricate diosgenin into nanoparticle by encapsulating with biodegradable polymer chitosan.
 Aim: The current research intends to uncover the therapeutic potency of diosgenin encapsulated chitosan nanoparticles (DG@CS-NP) on 7,12dimethylbenz(a)anthracene (DMBA) induced rat mammary carcinoma by optimizing biochemical and histopathological modifications via attenuating Aryl hydrocarbon receptor (AhR) - nuclear factor erythroid-derived 2-related factors (Nrf-2) signaling.
 Methodology: Breast cancer was induced with a single dose of DMBA (25 mg/kg b.wt). Orally supplied DG 10mg/kg b.wt. and DG@CS-NP 5 mg/kg b.wt to DMBA-induced tumor-bearing rats shortly after tumor onset. After the experimental period, biochemical and histopathological studies were performed using mammary tissue sections. Furthermore, architectural immunohistochemistry was used to reveal the expression of AhR and Nrf-2 in experimental rats. Additionally, diosgenin interactions with these proteins were also evidently confirmed by molecular docking analysis.
 Result: We noticed that there is an elevated level of lipid peroxidative marker, phase-I detoxification enzymes, total cholesterol (TC), phospholipids (PL), triglycerides (TG), and free fatty acids (FFA) with boosted AhR expressions as well as diminished levels of enzymatic and non-enzymatic antioxidants and Phase – II detoxification enzymes with downtrodden Nrf-2 expressions in the mammary tissues of DMBA-induced rats. On the other contrary, oral dosing of DG@CS-NP 5 mg/kg b.wt, dramatically reverted them to near-normal tiers. Interestingly, molecular docking analyses also corroborate these insights by highlighting diosgenin's significant interactions with AhR and Nrf-2 targets.
 Conclusion: As an outcome of our observations, we conclude that nano-encapsulation of diosgenin is a potent targeted therapeutic candidate posing a massive impact on breast cancer than plain diosgenin.

Creatine supplementation does not alter proliferation or doxorubicin sensitivity of mammary carcinoma cells

Objectives Doxorubicin (DOX) is an effective chemotherapy drug used to treat breast cancer, but its use is limited by detrimental side effects such as cardiotoxicity and skeletal muscle atrophy. Supplementation with creatine has been shown to protect cardiac and skeletal muscle cells from the cytotoxic effects of DOX. One concern with dietary creatine supplementation in cancer patients, however, is the possible protection of cancer cells from therapeutic DOX toxicity. Thus, we investigated the effects of in vitro creatine supplementation on proliferation and survival of DOX-treated MAT-BIII rat mammary carcinoma cells. Methods MATB-III cells were seeded in triplicate at 15,000 cells/well in a 96-well microplate for an eight day incubation in one of six treatments: no treatment, 5 µM DOX, 2 mM creatine, 2 mM creatine + 5 µM DOX, 20 mM creatine, 20 mM creatine + 5 µM DOX. Media and treatments were refreshed every 48 hours. An MTT assay was run on day 8 to assess remaining cell number in each well. The results represent an average from three time separated experiments with differences between treatments identified using a two-way ANOVA (IBM SPSS 27). Significance was at the α=0.05 level. Results As expected, the number of MAT-BIII cells was significantly reduced (P < 0.001) after DOX treatment consistent with impaired proliferation or cytotoxicity. Neither low nor high-dose creatine exposure altered the number of cells or the suppressive effects of DOX as no creatine x DOX interaction was identified (P > 0.05). Conclusion DOX decreased proliferation of MAT-BIII mammary carcinoma cells indicating this cell line is sensitive to the effects of this chemotherapy drug. There was no indication that creatine influenced proliferation or DOX sensitivity of the mammary carcinoma cells. The absence of an effect in this experiment suggests that creatine could be supplemented to alleviate the adverse side effects of DOX treatment in human breast cancer patients. Future research aims to elucidate further the possible interactions between DOX and creatine in cancer cell metabolism.

The Spinal α7-Nicotinic Acetylcholine Receptor Contributes to the Maintenance of Cancer-Induced Bone Pain.

IntroductionCancer-induced bone pain (CIBP) is acknowledged as a multifactorial chronic pain that tortures advanced cancer patients, but existing treatment strategies for CIBP have not been satisfactory yet. Investigators have demonstrated that the activation of α7-nAChRs exerts analgesic effects in some chronic pain models. However, the role of spinal α7-nAChRs in CIBP remains unknown. This study was designed to investigate the role of α7-nAChRs in a well-established CIBP model induced by Walker 256 rat mammary gland carcinoma cells.MethodsThe paw withdrawal threshold (PWT) of the ipsilateral hind paw was measured using von Frey filament. The expressions of spinal α7-nAChRs and NF-κB were measured with Western blotting analysis. Immunofluorescence was employed to detect the expression of α7-nAChRs and co-expressed of α7-nAChRs with NeuN or GFAP or Iba1.ResultsExperiment results showed that the expression of spinal α7-nAChRs was significantly downregulated over time in CIBP rats, and in both CIBP rats and sham rats, most of the α7-nAChRs located in neurons. Behavioral data suggested PNU-282,987, a selective α7-nAChRs agonist, dose-dependently produced analgesic effect and positive allosteric modulator could intensify its effects. Further, repeated administration of PNU-282,987 reversed the expression of α7-nAChRs, inhibited the nuclear factor kappa B (NF-κB) signaling pathway, and attenuates CIBP-induced mechanical allodynia state as well.ConclusionThese results suggest that the reduced expression of spinal α7-nAChRs contributes to the maintenance of CIBP by upregulating NF-κB expression, which implying a novel pharmacological therapeutic target for the treatment of CIBP.

Exome of Radiation-induced Rat Mammary Carcinoma Shows Copy-number Losses and Mutations in Human-relevant Cancer Genes.

Our understanding of cancer risk from neutron exposure is limited. We aimed to reveal the characteristics of mammary carcinomas induced by neutrons. Mammary carcinomas obtained from female Sprague-Dawley rats irradiated at 7 weeks of age with 0.97 Gy neutrons or 4 Gy γ-rays and from non-irradiated rats were classified into luminal and non-luminal subtypes by immunohistochemistry. Their mutational landscapes were determined by whole-exome sequencing. Neutrons significantly raised the incidence of luminal mammary carcinomas over the non-luminal subtype. Somatic mutations were identified in cancer genes involved in several signalling pathways, including Keap1/Nrf2, Pi3k/Akt and Wnt/β-catenin. Focal copy-number losses involving cancer genes were observed mainly in carcinomas from the irradiated rats. Neutrons increase the incidence of luminal mammary carcinomas, probably through gene mutations similar to those found in human breast cancers, and focal copy-number losses including cancer genes that are characteristics of radiation-induced mammary carcinomas.

Radiation Carcinogenesis in Animal Models: Part 1

Exposure to ionizing radiation (IR) increases the risk of cancers, as epidemiology studies of atomic bomb survivors and patients who have received radiotherapy show. The carcinogenic effects of IR are well-documented, although the effects of radiation carcinogenesis change in each organ. The mammary gland is known to be highly susceptible to radiation-induced cancer. We have previously reported that (i) differential DNA methylation patterns in rat mammary carcinomas induced by pre-and post-pubertal IR; (ii) the effect of parity on rat mammary carcinogenesis varies between pre-and post-pubertal IR. In this review, we summarize our radiation researches as well as related with other radiation researches in rodent models.

Rhus coriaria L. (Sumac) Demonstrates Oncostatic Activity in the Therapeutic and Preventive Model of Breast Carcinoma.

Comprehensive scientific data provide evidence that isolated phytochemicals or whole plant foods may beneficially modify carcinogenesis. The aim of this study was to evaluate the oncostatic activities of Rhus coriaria L. (sumac) using animal models (rat and mouse), and cell lines of breast carcinoma. R. coriaria (as a powder) was administered through the diet at two concentrations (low dose: 0.1% (w/w) and high dose: 1 % (w/w)) for the duration of the experiment in a syngeneic 4T1 mouse and chemically-induced rat mammary carcinoma models. After autopsy, histopathological and molecular analyses of tumor samples in rodents were performed. Moreover, in vitro analyses using MCF-7 and MDA-MB-231 cells were conducted. The dominant metabolites present in tested R. coriaria methanolic extract were glycosides of gallic acid (possible gallotannins). In the mouse model, R. coriaria at a higher dose (1%) significantly decreased tumor volume by 27% when compared to controls. In addition, treated tumors showed significant dose-dependent decrease in mitotic activity index by 36.5% and 51% in comparison with the control group. In the chemoprevention study using rats, R. coriaria at a higher dose significantly reduced the tumor incidence by 20% and in lower dose non-significantly reduced tumor frequency by 29% when compared to controls. Evaluations of the mechanism of oncostatic action using valid clinical markers demonstrated several positive alterations in rat tumor cells after the treatment with R. coriaria. In this regard, histopathological analysis of treated tumor specimens showed robust dose-dependent decrease in the ratio of high-/low-grade carcinomas by 66% and 73% compared to controls. In treated rat carcinomas, we found significant caspase-3, Bax, and Bax/Bcl-2 expression increases; on the other side, a significant down-regulation of Bcl-2, Ki67, CD24, ALDH1, and EpCam expressions and MDA levels. When compared to control specimens, evaluation of epigenetic alterations in rat tumor cells in vivo showed significant dose-dependent decrease in lysine methylation status of H3K4m3 and H3K9m3 and dose-dependent increase in lysine acetylation in H4K16ac levels (H4K20m3 was not changed) in treated groups. However, only in lower dose of sumac were significant decreases in the expression of oncogenic miR210 and increase of tumor-suppressive miR145 (miR21, miR22, and miR155 were not changed) observed. Finally, only in lower sumac dose, significant decreases in methylation status of three out of five gene promoters–ATM, PTEN, and TIMP3 (PITX2 and RASSF1 promoters were not changed). In vitro evaluations using methanolic extract of R. coriaria showed significant anticancer efficacy in MCF-7 and MDA-MB-231 cells (using Resazurin, cell cycle, annexin V/PI, caspase-3/7, Bcl-2, PARP, and mitochondrial membrane potential analyses). In conclusion, sumac demonstrated significant oncostatic activities in rodent models of breast carcinoma that were validated by mechanistic studies in vivo and in vitro.

Metformin potentiates the chemotherapeutic effects of doxorubicin on 2-amino-1-methyl-6-phenylimidazo[4,5b] pyridine-induced Mammary Carcinoma in rats.

This study was carried out to evaluate the antitumor activity of Metformin (Met) and its impending utility to potentiate the chemotherapeutic action of doxorubicin on 2-amino-1-methyl-6-phenylimidazo[4,5b]pyridine (PhIP)-induced rat mammary carcinogenesis. Female Sprague -Dawley (SD) rats were divided into seven groups (n=15 each). Mammary carcinogenesis was induced by the administration of PhIP at a dose of 75mg/kg by gavage. Met treatment was 2mg/ml in drinking water for 26weeks started after the last PhIP dose. Doxorubicin (Dox) treatment started after one month of the last PhIP dose with a dose of 4mg/kg, i.v. once per week for 4weeks. Compared to the PhIP group, the latency period of tumors in the PhIP+Dox, PhIP+Met, and PhIP+Dox+Met groups were significantly increased and tumors' incidences and multiplicities were significantly reduced. By immunohistochemistry, carcinomas from the combination treatment groups showed a significant decrease in the labeling indexes (LI%) of cellular proliferation and CD44 compared to the PhIP group while LI% for ERα was significantly decreased in all combination treatment groups compared to the PhIP-administered group. Moreover, the quantitative mRNA expression of ERα was significantly decreased in mammary tumors from PhIP+Dox+Met combined group more than the PhIP+Dox group. However, mRNA expression of EGF was found significantly lower in all combination treatment groups compared to the PhIP group. These findings suggest that Metformin potentiate the antitumor efficacy of doxorubicin and had beneficial effects on PhIP-induced mammary carcinogenesis through the prevention of cellular proliferation and mRNA expression of ERα and EGF.

Chemopreventive and Therapeutic Efficacy of Cinnamomum zeylanicum L. Bark in Experimental Breast Carcinoma: Mechanistic In Vivo and In Vitro Analyses.

Comprehensive oncology research suggests an important role of phytochemicals or whole plant foods in the modulation of signaling pathways associated with anticancer action. The goal of this study is to assess the anticancer activities of Cinnamomum zeylanicum L. using rat, mouse, and cell line breast carcinoma models. C. zeylanicum (as bark powder) was administered in the diet at two concentrations of 0.1% (w/w) and 1% (w/w) during the whole experiment in chemically induced rat mammary carcinomas and a syngeneic 4T1 mouse model. After autopsy, histopathological and molecular evaluations of mammary gland tumors in rodents were carried out. Moreover, in vitro analyses using MCF-7 and MDA-MB-231 cells were performed. The dominant metabolites present in the tested C. zeylanicum essential oil (with relative content over 1%) were cinnamaldehyde, cinnamaldehyde dimethyl acetal, cinnamyl acetate, eugenol, linalool, eucalyptol, limonene, o-cymol, and α-terpineol. The natural mixture of mentioned molecules demonstrated significant anticancer effects in our study. In the mouse model, C. zeylanicum at a higher dose (1%) significantly decreased tumor volume by 44% when compared to controls. In addition, treated tumors showed a significant dose-dependent decrease in mitotic activity index by 29% (0.1%) and 45.5% (1%) in comparison with the control group. In rats, C. zeylanicum in both doses significantly reduced the tumor incidence by 15.5% and non-significantly suppressed tumor frequency by more than 30% when compared to controls. An evaluation of the mechanism of anticancer action using valid oncological markers showed several positive changes after treatment with C. zeylanicum. Histopathological analysis of treated rat tumor specimens showed a significant decrease in the ratio of high-/low-grade carcinomas compared to controls. In treated rat carcinomas, we found caspase-3 and Bax expression increase. On the other hand, we observed a decrease in Bcl-2, Ki67, VEGF, and CD24 expressions and MDA levels. Assessment of epigenetic changes in rat tumor cells in vivo showed a significant decrease in lysine methylation status of H3K4m3 and H3K9m3 in the high-dose treated group, a dose-dependent increase in H4K16ac levels (H4K20m3 was not changed), down-regulations of miR21 and miR155 in low-dose cinnamon groups (miR22 and miR34a were not modulated), and significant reduction of the methylation status of two out of five gene promoters—ATM and TIMP3 (PITX2, RASSF1, PTEN promoters were not changed). In vitro study confirmed results of animal studies, in that the essential oil of C. zeylanicum displayed significant anticancer efficacy in MCF-7 and MDA-MB-231 cells (using MTS, BrdU, cell cycle, annexin V/PI, caspase-3/7, Bcl-2, PARP, and mitochondrial membrane potential analyses). As a conclusion, C. zeylanicum L. showed chemopreventive and therapeutic activities in animal breast carcinoma models that were also significantly confirmed by mechanistic evaluations in vitro and in vivo.

Chemokine receptor CXCR4 activates the RhoA/ROCK2 pathway in spinal neurons that induces bone cancer pain.

BackgroundChemokine receptor CXCR4 has been found to be associated with spinal neuron and glial cell activation during bone cancer pain. However, the underlying mechanism remains unknown. Furthermore, the RhoA/ROCK2 pathway serves as a downstream pathway activated by CXCR4 during bone cancer pain. We first validated the increase in the expressions of CXCR4, p-RhoA, and p-ROCK2 in the spinal dorsal horn of a well-characterized tumor cell implantation-induced cancer pain rat model and how these expressions contributed to the pain behavior in tumor cell implantation rats. We hypothesized that spinal blockade of the CXCR4-RhoA/ROCK2 pathway is a potential analgesic therapy for cancer pain management.MethodsAdult female Sprague–Dawley rats (body weight of 180–220 g) and six- to seven-week old female Sprague–Dawley rats (body weight of 80–90 g) were taken. Ascitic cancer cells were extracted from the rats (body weight of 80–90 g) with intraperitoneally implanted Walker 256 mammary gland carcinoma cells. Walker 256 rat mammary gland carcinoma cells were then injected (tumor cell implantation) into the intramedullary space of the tibia to establish a rat model of bone cancer pain.ResultsWe found increased expressions of CXCR4, p-RhoA, and p-ROCK2 in the neurons in the spinal cord. p-RhoA and p-ROCK2 were co-expressed in the neurons and promoted by overexpressed CXCR4. Intrathecal delivery of CXCR4 inhibitor Plerixafor (AMD3100) or ROCK2 inhibitor Fasudil abrogated tumor cell implantation-induced pain hypersensitivity and tumor cell implantation-induced increase in p-RhoA and p-ROCK2 expressions. Intrathecal injection of stromal-derived factor-1, the principal ligand for CXCR4, accelerated p-RhoA expression in naive rats, which was prevented by postadministration of CXCR4 inhibitor Plerixafor (AMD3100) or ROCK2 inhibitor Fasudil.ConclusionsCollectively, the spinal RhoA/ROCK2 pathway could be a critical downstream target for CXCR4-mediated neuronal sensitization and pain hypersensitivity in bone cancer pain, and it may serve as a potent therapeutic target for pain treatment.

The Possible protective effect of pumpkin seed extract on mammary carcinoma in rats: An experimental study

Objective: To evaluate the potential protective effect of pumpkins’ seed extract on oxidative stress and cyclin D1 expression associated with mammary gland carcinoma in rats. Design: Randomized controlled experimental study. Animals: Forty female Sprague Dawley rats. Procedures: Rats were allocated equally to four groups (10 rats each); group 1 (control group); group 2 received 7, 12 dimethylbenzanthracene (DMBA) subcutaneously in the mammary region to induce carcinoma. Group 3 received pumpkin seed extract at 300 mg/kg body weight orally, and group 4 was treated with both pumpkin seed extract and DMBA. Animals were euthanized after 8 weeks of treatment, and tissues from mammary gland were collected and divided into three portions. The first portion was used to determine antioxidant and oxidative stress markers; the second one was stored in RNA for later estimation of Cyclin D1 expression, and the last portion was stored in neutral buffered formalin (10%) for histopathological examination. Results: Levels of Nitric oxide, Malondialdehyde and Reduced Glutathione, as well as activity of Glutathione-S-transferase and superoxide dismutase (SOD) showed a significant decline in rats supplemented with pumpkin seed extract and subjected to induced mammary carcinoma in comparison with diseased non-supplemented rats (P <0.05). In addition, there was a down-expression in cyclin D1 expression in rats supplemented with pumpkin seed extract. Conclusion and clinical relevance: Pumpkins’ seed extract can alleviate the oxidative stress and cyclin D1 expression associated with experimentally induced mammary carcinoma in rats. Further studies are needed to get an evidence for the use of pumpkin seed extract in the clinical practice.

The possible protective effect of pumpkin seed extract on mammary carcinoma in rats: An experimental study

Objective: To evaluate the potential protective effect of pumpkins’ seed extract on oxidative stress and cyclin D1 expression associated with mammary gland carcinoma in rats. Design: Randomized controlled experimental study. Animals: Forty female Sprague Dawley rats. Procedures: Rats were allocated equally to four groups (10 rats each); group 1 (control group); group 2 received 7, 12 dimethylbenzanthracene (DMBA) subcutaneously in the mammary region to induce carcinoma. Group 3 received pumpkin seed extract at 300 mg/kg body weight orally, and group 4 was treated with both pumpkin seed extract and DMBA. Animals were euthanized after 8 weeks of treatment, and tissues from mammary gland were collected and divided into three portions. The first portion was used to determine antioxidant and oxidative stress markers; the second one was stored in RNA for later estimation of Cyclin D1 expression, and the last portion was stored in neutral buffered formalin (10%) for histopathological examination. Results: Nitric oxide, Malondialdehyde, Reduced Glutathione, Glutathione-S-transferase and superoxide dismutase (SOD) showed a significant decline in rats supplemented with pumpkin seed extract and subjected to induced mammary carcinoma in comparison with diseased non-supplemented rats (P &lt;0.05). In addition, there was a down-expression in cyclin D1 expression in rats supplemented with pumpkin seed extract. Conclusion and clinical relevance: Pumpkins’ seed extract can alleviate the oxidative stress and cyclin D1 expression associated with experimentally induced mammary carcinoma in rats. Further studies are needed to get an evidence for the use of pumpkin seed extract in the clinical practice.

Paxillin serine 178 phosphorylation in control of cell migration and metastasis formation through regulation of EGFR expression in breast cancer

Paxillin is a well-known multidomain scaffold protein that is involved in the regulation of cell-matrix adhesiondynamics, a process required for the tumor cell migration and invasion. Phosphorylation of the serine residue 178requires c-Jun NH2-terminal kinase (JNK) activation, which occurs downstream of epidermal growth factor receptor (EGFR)-mediated signaling and drives cell migration. In this study, we investigated the significance of paxillin Ser178 phosphorylation in breast cancer progression.We employed the rat mammary carcinoma MTLn3 cell line with which we established stabile variants of both wild type and mutant GFP-paxillin constructs. With those, we next performed several in vitro assays including cell proliferation, migration and focal adhesion dynamics. Finally, we monitored the metastatic spread of both cell line variants in an othrotopic mouse model for breast cancer.Here we show that expression of the phospho-defective mutant paxillinS178A in the metastatic mammary adenocarcinoma MTLn3 cell-line significantly decreased EGF-induced cell migration, which was correlated with impaired focal adhesion dynamics. Moreover, paxillinS178A attenuated lung metastasis formation in an orthotopic in vivo mammary gland tumor/metastasis model, demonstrating the importance of JNK-mediated paxillin phosphorylation in breast cancer progression. Expression of paxillinS178A caused a decrease in EGFR expression while re-expression of EGFR in MTLn3-paxillinS178A cells fully restored EGF-driven cell motility and focal adhesion dynamics. Furthermore, re-expression of EGFR in MTLn3-paxillinS178A rescued spontaneous metastasis from breast to lung.Overall our data show an important role for JNK-mediated paxillin Ser178 phosphorylation in the regulation of EGFR expression and thereby, in EGF-driven cell migration and metastasis formation.

Anticancer Activities of Thymus vulgaris L. in Experimental Breast Carcinoma in Vivo and in Vitro.

Naturally-occurring mixtures of phytochemicals present in plant foods are proposed to possess tumor-suppressive activities. In this work, we aimed to evaluate the antitumor effects of Thymus vulgaris L. in in vivo and in vitro mammary carcinoma models. Dried T. vulgaris (as haulm) was continuously administered at two concentrations of 0.1% and 1% in the diet in a chemically-induced rat mammary carcinomas model and a syngeneic 4T1 mouse model. After autopsy, histopathological and molecular analyses of rodent mammary carcinomas were performed. In addition, in vitro evaluations using MCF-7 and MDA-MB-231 cells were carried out. In mice, T. vulgaris at both doses reduced the volume of 4T1 tumors by 85% (0.1%) and 84% (1%) compared to the control, respectively. Moreover, treated tumors showed a substantial decrease in necrosis/tumor area ratio and mitotic activity index. In the rat model, T. vulgaris (1%) decreased the tumor frequency by 53% compared to the control. Analysis of the mechanisms of anticancer action included well-described and validated diagnostic and prognostic markers that are used in both clinical approach and preclinical research. In this regard, the analyses of treated rat carcinoma cells showed a CD44 and ALDH1A1 expression decrease and Bax expression increase. Malondialdehyde (MDA) levels and VEGFR-2 expression were decreased in rat carcinomas in both the T. vulgaris treated groups. Regarding the evaluations of epigenetic changes in rat tumors, we found a decrease in the lysine methylation status of H3K4me3 in both treated groups (H3K9m3, H4K20m3, and H4K16ac were not changed); up-regulations of miR22, miR34a, and miR210 expressions (only at higher doses); and significant reductions in the methylation status of four gene promoters—ATM serin/threonine kinase, also known as the NPAT gene (ATM); Ras-association domain family 1, isoform A (RASSF1); phosphatase and tensin homolog (PTEN); and tissue inhibitor of metalloproteinase-3 (TIMP3) (the paired-like homeodomain transcription factor (PITX2) promoter was not changed). In vitro study revealed the antiproliferative and proapoptotic effects of essential oils of T. vulgaris in MCF-7 and MDA-MB-231 cells (analyses of 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium) (MTS); 5-bromo-20-deoxyuridine (BrdU); cell cycle; annexin V/PI; caspase-3/7; Bcl-2; PARP; and mitochondrial membrane potential). T. vulgaris L. demonstrated significant chemopreventive and therapeutic activities against experimental breast carcinoma.

Neutron-induced Rat Mammary Carcinomas Are Mainly of Luminal Subtype and Have Multiple Copy Number Aberrations.

Neutrons are used as a type of high linear energy transfer (LET) radiation and they have stronger carcinogenic effects compared to low LET radiation. We sought to clarify the features of mammary carcinomas for which the incidence increases when these were exposed to neutron radiation. We compared mammary carcinomas from female Sprague-Dawley rats irradiated at 7 weeks of age with 0.485 Gy neutron beams or 0.5-Gy γ rays, with carcinomas of non-irradiated rats. Tumors were classified into luminal and non-luminal subtypes based on immunohistochemistry, while their copy number aberrations were determined using microarrays. Neutrons and γ rays significantly increased the incidence of luminal carcinomas. The carcinomas in the three groups contained multiple aberrations affecting 46 genes for which mutations have been reported in human breast cancer. Neutrons and γ rays increase the incidence of luminal mammary carcinoma in rats, probably via genetic aberrations similar to those found in human breast cancer patients.

Amitriptyline influences the mechanical withdrawal threshold in bone cancer pain rats by regulating glutamate transporter GLAST.

Patients with cancer, especially breast, prostate, and lung cancer, commonly experience bone metastases that are difficult to manage and are associated with bone cancer pain. Amitriptyline is often used to treat chronic pain, such as neuropathic pain. In this study, the effects of amitriptyline on the mechanical withdrawal threshold and its underlying mechanisms were evaluated in rat models of bone cancer pain. Walker 256 rat mammary gland carcinoma cells were injected into the bone marrow cavity of the right tibia of rats to provoke bone cancer pain. Then, amitriptyline was intraperitoneally administered twice daily from fifth day after the operation. Rats with bone cancer showed an apparent decline in the mechanical withdrawal threshold at day 11 after Walker 256 cells inoculation. The levels of the glutamate-aspartate transporter in the spinal cord dorsal horn decreased remarkably, and the concentration of the excitatory amino acid glutamate in the cerebrospinal fluid increased substantially. Amitriptyline injection could prevent the decline of mechanical withdrawal threshold in bone cancer pain rats. In addition, glutamate-aspartate transporter was upregulated on the glial cell surface, and glutamate levels were reduced in the cerebrospinal fluid. However, amitriptyline injection could not prevent the bone cancer pain-induced reduction in glutamate-aspartate transporter in the glial cell cytosol, it further downregulated cytosolic glutamate-aspartate transporter. Amitriptyline had no significant effect on GLAST messenger RNA expression, and bone cancer pain-invoked protein kinase A/protein kinase C upregulation was prevented. Taken together, these results suggest that the intraperitoneal injection of amitriptyline can prevent the decrease of mechanical withdrawal threshold in bone cancer pain rats, the underlying mechanisms may be associated with the inhibition of protein kinase A/protein kinase C expression, thus promoting glutamate-aspartate transporter trafficking onto the glial cell surface and reducing excitatory amino acid concentrations in the cerebrospinal fluid.