Rat Mammary Tumors Research Articles

Promoting effect of sunset yellow on N-methyl N-nitrosourea-induced rat mammary carcinogenesis: Implications of molecular mechanisms

BackgroundNowadays, the use of food additives, such as Sunset Yellow (SY), is growing, which attracted attention to the potential relationship between some diseases and food additives. AimThe study aimed to investigate the role of Sunset Yellow during chemically-induced mammary gland carcinogenesis in Sprague–Dawley rats. Material and methodsThree groups of female rats were intraperitoneally administered with N-methyl-N-nitrosourea (MNU). Group 1 was set on a basal diet. Group 2 was treated with 161.4 mg\\kg\\day Sunset Yellow (SY). Group 3 was given SY at 80.7 mg\\kg\\day. Groups 4–6 were not administered MNU; Group 4 received vehicles only. Groups 5 and 6 were administered SY similarly to groups 2 and 3 respectively. ResultsSunset Yellow at both doses exerted a significant dose-dependent increase in tumor incidences, multiplicities, volumes, and decreased tumor latency as compared with control. Immunolabeling indexes of the proliferating cell nuclear antigen, estrogen receptor alpha, and progesterone receptor were significantly increased after SY treatment. Oxidative stress markers, serum estrogen, progesterone, and prolactin levels were significantly modified by SY treatment. The mRNA expression of estrogen receptor alpha and epidermal growth factor was up-regulated in SY groups versus control. ConclusionCollectively, SY has significantly promoted MNU-induced mammary tumors in rats with underlying mechanisms correlating SY consumption with estrogen disruption and subsequent antioxidative stress discrepancy.

Pyridoxamine Attenuates Doxorubicin-Induced Cardiomyopathy without Affecting Its Antitumor Effect on Rat Mammary Tumor Cells.

Doxorubicin (DOX) is commonly used in cancer treatment but associated with cardiotoxicity. Pyridoxamine (PM), a vitamin B6 derivative, could be a cardioprotectant. This study investigated the effect of PM on DOX cardiotoxicity and DOX antitumor effectiveness. Sprague Dawley rats were treated intravenously with DOX (2 mg/kg/week) or saline over eight weeks. Two other groups received PM via oral intake (1 g/L in water bottles) next to DOX or saline. Echocardiography was performed after eight weeks. PM treatment significantly attenuated the DOX-induced reduction in left ventricular ejection fraction (72 ± 2% vs. 58 ± 3% in DOX; p < 0.001) and increase in left ventricular end-systolic volume (0.24 ± 0.02 µL/cm2 vs. 0.38 ± 0.03 µL/cm2 in DOX; p < 0.0001). Additionally, LA7 tumor cells were exposed to DOX, PM, or DOX and PM for 24 h, 48 h, and 72 h. Cell viability, proliferation, cytotoxicity, and apoptosis were assessed. DOX significantly reduced LA7 cell viability and proliferation (p < 0.0001) and increased cytotoxicity (p < 0.05) and cleaved caspase-3 (p < 0.001). Concomitant PM treatment did not alter the DOX effect on LA7 cells. In conclusion, PM attenuated DOX-induced cardiomyopathy in vivo without affecting the antitumor effect of DOX in vitro, highlighting PM as a promising cardioprotectant for DOX-induced cardiotoxicity.

Exploration of tumor growth regression of quinoa and chia oil nanocapsules via the control of PIK3CA and MYC expression, anti-inflammation and cell proliferation inhibition, and their hepatorenal safety in rat breast cancer model

BackgroundThe second most common cancer in the world is breast cancer. Chemotherapy is used to treat breast cancer, but instances of multidrug resistance, targets that are not selective, and physicochemical issues raise doubts about its efficacy. So, the exploration of chemopreventive agents from efficient natural sources has been required. The chia and quinoa seeds have health-promoting activities that include cardio-protective, antidiabetic, and anticancer effects. Given the paramount importance of their oils and their potential bioactivities, this work aimed to assess the repressive effect of their oil nanocapsules against mammary tumors in rats. Rat models of chemically induced mammary tumors were gavaged with chia and quinoa nanocapsules for one month. The repressive effect of nanocapsules was studied by quantifying TNF-α, assessing the gene expression of proto-oncogenes (PIK3CA and MYC) using qRT-PCR, and analyzing the cell cycle in mammary tissue.ResultsThe studies clarified that the inhibition of tumors in response to quinoa and chia nanocapsules was associated with a reduction in TNF-α levels, proliferation capability, and motivation for apoptosis. Furthermore, quinoa and chia nanocapsule management repressed the activation of the MYC and PIK3CA genes. As well as nanocapsules modulated the liver enzymes and kidney function alterations induced in mammary tumor animals. Meanwhile, both oils' nanocapsules do not have an impact on the liver and kidneys of healthy rats.ConclusionsThe findings indicate that quinoa and chia nanocapsules are safe and can reduce tumor growth, suggesting a potential natural therapeutic target for breast cancer treatment.

Study on the Therapeutic Effect and Some Immune factors by Methotrexate Modified Superparamagnetic Nanoparticles in Rat Mammary Tumors

Objective: This study investigates the efficacy, immunological impact, and preliminary safety of methotrexate (MTX) modified magnetic Fe3O4 nanoparticles in thermochemotherapy for mammary tumors in rats. Methods: Transmission electron microscopy images...

Zerumbone (ZER), a Potential Anticancer for Breast Mediates Cancer Cell Death Through Targeting β-catenin Signaling Pathway in Tumor Regression in Sprague Dawley Rat Mammary Gland Tumors

Background &amp; Objective: Canonical WNT/Wingless pathway regulates expression of target genes by modulating intracellular β-catenin leading to cancer growth and survival. Here, we studied inhibition of β-catenin using zerumbone (ZER) or β-catenin-siRNA in Sprague-Dawley rat cancer model. Methodology: Rat mammary gland tumor model was induced with the wild-type LA7 breast cancer cell line or β-catenin-knockdown-LA7 cells. LA7-rats were treated with ZER or β-catenin-siRNA as a positive control and the levels of β-catenin expression and its target gene were assessed using real-time PCR, immunohistochemistry and TUNEL assay. Results: We found good correlation between β-catenin inhibition and induction of apoptosis when using ZER or β-catenin-siRNA. In this aspect, ZER and β-catenin-siRNA inhibited cellular proliferation as reflected by reduced growth of breast cancer and apoptosis induction in rat mammary gland tumor. Further, our studies demonstrate that treatment with ZER and β-catenin-siRNA affected β-catenin-dependent gene expression. β-catenin downregulation by ZER or knockdown by β-catenin-siRNA improves the morphological and histological feature of the breast tissues as confirmed by subtle changes of the genes involved in cell-apoptotic pathways. Conclusion: This indicates that ZER targets similarly to β-catenin-siRNA and possibly be a useful anti-breast cancer by affecting expression of down-stream targets that are key components in cancer development. ZER can be a promising anticancer candidate for treatment of breast.

Modulation of mammary tumour progression using murine model by ethanol root extract of Saussurea costus (falc.) lipsch

Ethnopharmacological relevanceBreast cancer is a major cause of death among human females across the globe. The anti-neoplastic agents or therapies used for the treatment of cancers can enhance longevity but are subsequently observed to deteriorate the quality of life due to the extensive side effects produced. Saussurea costus is a potential medicinal plant of the Himalayas with noticeable ethnopharmacological properties. The phytochemicals present in Saussurea costus are responsible for anti-carcinogenic potential and warranted nil or minimal side effects of Saussurea costus and directed to use this plant as a preventive or therapeutic drug candidate against cancers. Aim of the studyThe present study was planned to evaluate the anti-neoplastic activity of Saussurea costus root extract (SL) in rat mammary tumour model. Materials and methodsThe anti-neoplastic activity of SL root extract at 3 different doses (100, 250 and 500 mg/kg BW) for 18 weeks against 12-dimethylbenz (a) anthracene (DMBA)-induced mammary tumours in Sprague Dawley (SD) female rats was analyzed through serum biochemistry (ALT, AST, ALP, Total protein, Creatinine and BUN), oxidative stress parameters (Lipid peroxidation, Catalase and Reduced glutathione), pro-inflammatory cytokines (TNF-α and NF-κB), immunohistochemical markers (Ki-67, MMP-9 and VEGF), real-time PCR (PCNA, p53, bax, bcl-2 and caspase-3, genes) and molecular docking. ResultsInhibition of tumour parameters, minimal alteration in the liver (ALT, AST and ALP) and kidney enzymes (Creatinine and BUN), decreased activity of MDA, elevated levels of GSH and catalase, reduction in the levels of pro-inflammatory cytokines i.e. TNF-α and NF-κB, reduced gross and histomorphological changes, declined expression of Ki-67, MMP-9 and VEGF in vivo rat model, mRNA expression of cancer-related genes and docking of dehydrocostus lactone and costunolide with NF-κB and TNF-α demonstrated the chemopreventive action of SL root extract. ConclusionsThe in-vivo trial elucidates anti-neoplastic activity of Saussurea costus root extract as demonstrated through the reduction of biochemical indices, oxidative stress parameters, histological changes, pro-inflammatory cytokines (NF-κB and TNF-α), cellular proliferation (Ki-67), metastases (MMP-9) and neovascularization (VEGF) markers with highest anti-neoplastic effect of SL extract at the dose of 500 mg/kg body weight. Therefore, the present study signifies the need to use the active principles present in the root extract of Saussurea costus against breast cancer as a therapeutic regimen.

Synthesis and antitumor activity of a 2-hydroxy substituted chalcone (C6)

Cancers account for approximately 13% of all deaths each year with breast cancer being one of the most common. Chemotherapeutic agents used in cancer usually have nonspecific toxicity which kills both tumor and normal cells and cause serious side effects that often limit their efficacy. This study aimed to synthesize chalcone and evaluate its antitumor activity. Chalcone was synthesized using Claisen-Schmidt condensation and characterized using spectroscopic techniques. The LD50 of the synthesized compound was estimated using OECD-425 guidelines in rats. A mammary tumor was induced with a single subcutaneous administration of 65 mg/kg of 1-methyl nitrosourea (MNU). The rats were palpated weekly to determine the size of the tumor. Eight weeks post MNU administration, the rats were divided into five groups of six rats each and treated with graded doses (12.5, 25, and 50 mg/kg) of the compound and paclitaxel (10 mg/kg) for six weeks. Before treatment, three rats were randomly selected and sacrificed, and mammary gland samples were subjected to histological assessment to confirm the induction of the tumor. At the end of the treatment, the rats were euthanized, and mammary glands were collected and subjected to histological evaluation. The possible mechanism of action of the synthesized compound was elucidated in silico using molecular docking. The compound was synthesized and named C6. C6 was found to be relatively safe with LD50 above 2000 mg/kg and exhibited remarkable antitumor activity. MNU-induced mammary tumor rats treated with C6 produced a significant decrease in tumor diameter when compared with the untreated group, histology slides displayed fewer signs of hyperplasia and small numbers of connective tissue with larger lobules when compared with the untreated group. In silico tubulin-binding interactions revealed that C6 binding to tubulin was like that of colchicine, and also has higher affinity to tubulin than colchicine. The synthesized chalcone demonstrated significant antitumor activities in MNU-induced mammary tumors in rats postulated via inhibition of tubulin polymerization.

Synthesis and anti-tumor activity of piperonal substituted chalcone

Objectives: Chalcones have been identified as potential antitumor agents with a novel target, the tubulin. The aim of the study was to synthesize a piperonal substituted chalcone and evaluate its in vivo antitumor activity. Materials and Methods: Piperonal substituted chalcone was synthesized using Claisen-Schmidt condensation and characterized using various spectroscopic techniques. The lethal dose (LD50) of the synthesized compound was estimated using OECD-425 guidelines in rats. Antitumor activity of the synthesized compound was evaluated on 1-methyl nitrosourea (MNU)-induced mammary tumor in female Wistar rats. Histological evaluation was used to confirm tumor induction and assess treatment with the synthesized compound. The possible mechanism of action of the synthesized compound was elucidated in silico using molecular docking. Results: The compound was synthesized and named C2. C2 was found to be relatively safe with LD50 &gt;2000 mg/kg orally. Moreover, C2 exhibited remarkable antitumor activity, at all the tested doses in a dose dependent manner. Histological evaluation of the MNU-induced mammary tumor rats treated with C2 displayed fewer signs of hyperplasia and small numbers of connective tissue with larger lobules when compared with the untreated group. In silico tubulin-binding interactions revealed that the kinetics of C2 binding to tubulin was like that of colchicine. Comparison of crystal structures of tubulin-C2 and tubulin-colchicine complexes showed that the binding mode of C2 to tubulin was like that of colchicine to tubulin and produced the same conformational changes on the tubulin structure as colchicine. Conclusion: The synthesized chalcone demonstrated remarkable antitumor activities in MNU-induced mammary tumors in rats possibly through inhibition of tubulin polymerization.

Potential Antitumor Effect of α-Mangostin against Rat Mammary Gland Tumors Induced by LA7 Cells.

In this study, the chemotherapeutic effect of α-mangostin (AM) was assessed in rats injected with LA7 cells. Rats received AM orally at 30 and 60 mg/kg twice a week for 4 weeks. Cancer biomarkers such as CEA and CA 15-3 were significantly lower in AM-treated rats. Histopathological evaluations showed that AM protects the rat mammary gland from the carcinogenic effects of LA7 cells. Interestingly, AM decreased lipid peroxidation and increased antioxidant enzymes when compared to the control. Immunohistochemistry results of the untreated rats showed abundant PCNA and fewer p53-positive cells than AM-treated rats. Using the TUNEL test, AM-treated animals had higher apoptotic cell numbers than those untreated. This report revealed that that AM lessened oxidative stress, suppressed proliferation, and minimized LA7-induced mammary carcinogenesis. Therefore, the current study suggests that AM has significant potential for breast cancer treatment.

In-vivo anticancer efficacy of self-targeted methotrexate-loaded polymeric nanoparticles in solid tumor-bearing rat

Here, cytotoxicity and antitumor efficacy against a chemically (N-methyl-N-nitrosourea) generated mammary tumor in rats were assessed using methotrexate-loaded chitosan nanoparticles (Meth-Cs-NPs). Meth-Cs-NPs intravenous administrated resulted in noticeably decreased tumor incidence, multiplicity, and weight. Further, kidney function tests for the treated groups resulted in noticeably decreased ALP (Meth-Cs-NPs; 244±15, diseases control; 403±14 U/L), Creatinine (Meth-Cs-NPs; 0.81±0.05, diseases control; 2±0.05mg/dl), and Urea (Meth-Cs-NPs; 56.62±5, diseases control; 113±6mg/dl) levels, close to a normal control group. Similarly, liver function tests showed significantly decreased serum biomarkers, SGPT (Meth-Cs-NPs; 40±1.8, diseases control; 84±1.9 U/L) and SGOT (Meth-Cs-NPs; 15±2, diseases control; 55±4 U/L) levels in treated groups as compared to the untreated group (diseases control). From the results, pro-inflammatory cytokines were also markedly reduced in the treated group such as, TNF-α (Meth-Cs-NPs; 17.31±1.15, diseases control; 36.9±5pg/mL), IL-1β (Meth-Cs-NPs; 433.3±66.5, diseases control; 1540±131.1pg/mL), and IL-6 (Meth-Cs-NPs; 1515±53, diseases control; 2200.6±69pg/mL) levels. Whereas Meth-Cs-NPs not only helped in lowering tumor multiplicity rates but also decrease inflammation. The studies could be successfully performed in chemically induced mammary tumors due to their easy, quick tumor growth and low mortality rates in rat models. According to the current study, Meth-Cs-NPs have high treatment potency and represent a possible therapeutic alternative for breast cancer treatment.

Abstract 5250: Effect of the β-blocker carvedilol in preventing DMBA-induced mammary gland tumor growth

Abstract According to global cancer statistics, breast cancer has now become the most diagnosed cancer and has become the fifth leading cause of cancer-related deaths worldwide. A promising method of retarding cancer-related mortality is cancer chemoprevention. However, there is no drug available that can be used routinely as a breast cancer-preventative agent. As carvedilol (CAR), an FDA-approved beta-adrenergic receptor blocker, reduces breast cancer mortality, we hypothesized that CAR might act as a breast cancer preventative agent. Three protocols were utilized to evaluate the ability of CAR to prevent 7,12-Dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats. In protocol 1, two doses of CAR (2 and 10 mg/kg) were administered in drinking water as a 7-day pretreatment and throughout the study. In protocol 2, 10 mg/kg tamoxifen and 10 mg/kg carvedilol were provided as a 7-day pretreatment, and treatment was halted after six weeks. In protocol 3, CAR and the non-β-blocking enantiomer R-carvedilol (10 mg/kg) were given as a 7-day pretreatment and throughout the study. In all studies, animals were palpated weekly beginning at week 5 to detect the presence and location of mammary tumors. Tumors were measured using a caliper, and the experiments terminated at week 13. In protocol 1, only 10 mg/kg CAR was effective in delaying DMBA-mediated tumor occurrence (p = 0.0002); the first appearance of tumors and median tumor appearance in CAR-treated rats were separated from rats receiving DMBA alone by 2 and 4 weeks, respectively. However, tumors that did form grew at the same rate in all groups. In protocol 2, tamoxifen served as a control to prevent DMBA-mediated tumors; only one tamoxifen-treated rat developed a tumor at the end of the study. The tamoxifen-treated rats tumor formation was not statistically different than negative controls; however, the CAR group was not statistically different from the DMBA group. In protocol 3, CAR and R-CAR treatment showed delayed tumor formation and growth compared to the DMBA-only group, although not statistically significant. Combining all DMBA and 1-week pretreatment CAR data (n = 58 and 40, respectively), CAR effectively prevents DMBA-induced tumor incidence (p = 0.001), with a 3-week differential in the median tumor formation between the two groups. Therefore, continuous CAR treatment is essential to achieve the observed chemopreventive effects. As carvedilol is a clinically used beta-blocker, the results provide significant implications in breast cancer chemoprevention. Citation Format: Pabitra Kumar Sardar, Steven Yeung, Ayaz Shahid, Bradley T. Andresen, Ying Huang. Effect of the β-blocker carvedilol in preventing DMBA-induced mammary gland tumor growth. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5250.

Asymmetric Dimethylarginine in an NMU-induced Rat Mammary Tumor Model.

Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of nitric oxide (NO) production and a newly discovered risk factor involved in endothelial dysfunction and adverse cardiovascular events. Recently, both NO and ADMA have also emerged as molecules of interest in carcinogenesis and tumor growth progression. Our earlier studies have confirmed elevated plasma ADMA levels in patients with hematological malignancies. However, the cause of elevated ADMA was unclear. The aim of this study was to assess the concentrations of ADMA, symmetric dimethylarginine (SDMA) and L-arginine in rats exposed to N-nitroso-N-methylurea (NMU) for the induction of mammary tumors. A total of 95 female rats of the Sprague-Dawley strain were used in the study. Plasma concentrations of ADMA, SDMA and L-arginine were quantified and statistically analyzed. Mean ADMA levels were higher in the tumor-bearing group compared to the control group. Mean plasma levels of SDMA and L-Arginine were not significantly different between the groups. The L-ARG/ADMA ratio was lower in rats with tumors compared to controls. Histological assessment confirmed expression of ADMA within the tumor cells, which strongly suggests that these tumor cells were the source of ADMA. Other studies are warranted to further explain the role of ADMA in neoplastic diseases.

Surgical management of spontaneous mammary tumor in rats (Rattus norvegicus domestica)

Surgical management of spontaneous mammary tumor in rats (Rattus norvegicus domestica)

Dual projection generalized sidelobe canceller based on mixed signal subspace for ultrasound imaging.

In this paper, we propose a dual projection generalized sidelobe canceller (DPGSC) based on mixed subspace (MS) for ultrasound imaging, which aims to improve the speckle signal-noise-ratio (sSNR) and decrease the dark-region artifacts. A mixed signal subspace based on the correlation between the desired steering vector and the eigenvectors is constructed to further optimize the desired steering vector and the final weight vector. The simulated and experimental results show that the proposed method can greatly improve the speckle uniformity. In the geabr_0 experiment, the standard deviation of background and sSNR of MS-DPGSC can be improved by 48.07% and 58.49% more than those of eigenspace-based generalized sidelobe canceller (ESGSC). Furthermore, for a hyperechoic target, the maximal improvement of contrast ratio is 95.29%. In terms of anechoic cyst, the contrast-to-noise ratio of MS-DPGSC is increased by 123.08% than that of ESGSC. The rat mammary tumor experimental data show that the proposed method has better comprehensive imaging effect than traditional generalized sidelobe cancellers and ESGSCs.

Label-free multimodal nonlinear optical imaging of needle biopsy cores for intraoperative cancer diagnosis.

.Significance: Needle biopsy (NB) procedures are important for the initial diagnosis of many types of cancer. However, the possibility of NB specimens being unable to provide diagnostic information, (i.e., non-diagnostic sampling) and the time-consuming histological evaluation process can cause delays in diagnoses that affect patient care.Aim: We aim to demonstrate the advantages of this label-free multimodal nonlinear optical imaging (NLOI) technique as a non-destructive point-of-procedure evaluation method for NB tissue cores, for the visualization and characterization of the tissue microenvironment.Approach: A portable, label-free, multimodal NLOI system combined second-harmonic generation (SHG) and third-harmonic generation and two- and three-photon autofluorescence (2PF, 3PF) microscopy. It was used for intraoperative imaging of fresh NB tissue cores acquired during canine cancer surgeries, which involved liver, lung, and mammary tumors as well as soft-tissue sarcoma; in total, eight canine patients were recruited. An added tissue culture chamber enabled the use of this NLOI system for longitudinal imaging of fresh NB tissue cores taken from an induced rat mammary tumor and healthy mouse livers.Results: The intraoperative NLOI system was used to assess fresh canine NB specimens during veterinary cancer surgeries. Histology-like morphological features were visualized by the combination of four NLOI modalities at the point-of-procedure. The NLOI results provided quantitative information on the tissue microenvironment such as the collagen fiber orientation using Fourier-domain SHG analysis and metabolic profiling by optical redox ratio (ORR) defined by 2PF/(2PF + 3PF). The analyses showed that the canine mammary tumor had more randomly oriented collagen fibers compared to the tumor margin, and hepatocarcinoma had a wider distribution of ORR with a lower mean value compared to the liver fibrosis and the normal-appearing liver. Moreover, the loss of metabolic information during tissue degradation of fresh murine NB specimens was shown by overall intensity decreases in all channels and an increase of mean ORR from 0.94 (standard deviation 0.099) to 0.97 (standard deviation 0.077) during 1-h longitudinal imaging of a rat mammary tumor NB specimen. The tissue response to staurosporine (STS), an apoptotic inducer, from fresh murine liver NB specimens was also observed. The mean ORR decreased from 0.86 to 0.74 in the first 40 min and then increased to 0.8 during the rest of the hour of imaging, compared to the imaging results without the addition of STS, which showed a continuous increase of ORR from 0.72 to 0.75.Conclusions: A label-free, multimodal NLOI platform reveals microstructural and metabolic information of the fresh NB cores during intraoperative cancer imaging. This system has been demonstrated on animal models to show its potential to provide a more comprehensive histological assessment and a better understanding of the unperturbed tumor microenvironment. Considering tissue degradation, or loss of viability upon fixation, this intraoperative NLOI system has the advantage of immediate assessment of freshly excised tissue specimens at the point of procedure.

SGK1 in Cancer: Biomarker and Drug Target.

Serum- and glucocorticoid-regulated kinases (SGKs) are members of the AGC family of serine/threonine kinases, consisting of three isoforms: SGK1, SGK2, and SGK3. SGK1 was initially cloned as a gene transcriptionally stimulated by serum and glucocorticoids in rat mammary tumor cells. It is upregulated in some cancers and downregulated in others. SGK1 increases tumor cell survival, adhesiveness, invasiveness, motility, and epithelial to mesenchymal transition. It stimulates tumor growth by mechanisms such as activation of K+ channels and Ca2+ channels, Na+/H+ exchanger, amino acid and glucose transporters, downregulation of Foxo3a and p53, and upregulation of β-catenin and NFκB. This chapter focuses on major aspects of SGK1 involvement in cancer, its use as biomarker as well as potential therapeutic target.

Gene Expression Changes by Diallyl Trisulfide Administration in Chemically-induced Mammary Tumors in Rats.

Diallyl trisulfide (DATS) was shown to be a potent inhibitor of luminal-type MCF-7 xenograft growth in vivo. The present study was conducted to determine the preventive effect of DATS administration using an N-methyl-N-nitrosourea (MNU)-induced rat mammary tumor model, which shares molecular resemblance to luminal-type human breast cancers. The DATS administration (50 mg/kg body weight, 5 times/week) was safe, but did not reduce mammary tumor latency, incidence, burden or multiplicity. Therefore, we conducted RNA-seq analysis using mammary tumors from control and DATS-treated rats (n = 3 for each group) to gain insights into lack of mammary tumor prevention by this phytochemical. The gene ontology and the Kyoto encyclopedia of genes and genomes pathway analyses of the RNA-seq data revealed upregulation of genes associated with ribosomes, translation, peptide biosynthetic/metabolic process, and oxidative phosphorylation but downregulation of genes associated with mitogen-activated protein kinases. A total of 33 genes associated with ribosomes were significantly upregulated by DATS treatment, including RPL11 and RPS14. Western blotting confirmed upregulation of RPL11 and neurofascin protein expression in mammary tumors from DATS-treated rats when compared to controls. A statistically significant increase in protein level of c-Jun N-terminal kinase 2 was also observed in tumors from DATS-treated rats when compared to controls. On the other hand, expression of complex I subunits NDUFV1 or NDUFS1 was not affected by DATS treatment. These results offer potential explanations for ineffectiveness of DATS in the chemically-induced rat mammary tumor model. Inhibitors of the proteins upregulated by DATS may be needed to improve chemopreventive efficacy of this phytochemical.

Application of condition coherence factor based on truncated composite method in ultrasound imaging

The coherence factor (CF) can improve the image contrast and side lobe suppression ability of traditional delay and sum (DAS) beamformer. However, it always leads to dark-region artifacts. In this paper, in order to reduce the dark-region artifacts while maintaining the image resolution and contrast as much as possible, a truncated-composite-based condition coherence factor (TC-CCF) is proposed for ultrasound imaging. Initially, the condition coherence factor (CCF) is defined as the ratio between the number of sampling time which should satisfy the condition of sign consistency and the total number of sampling time within the duration of a transmitting pulse. Then, setting a truncation threshold to truncate the CF and CCF, and the proposed truncated-composite condition coherence factor is obtained by combining the two truncated coherence factor. To evaluate the performance of the proposed methods, the simulation, the geabr_0 experiment, and the in vivo rat mammary tumor study is conducted. The simulated cyst indicates that TC-CCF can obtain better performance than CF and SCF in speckle quality. The geabr_0 experimental results demonstrate that the TC-CCF can gain 34.1% lower full width at half-maximum (FWHM) and 41.7% higher contrast ratio (CR) than traditional DAS. Furthermore, for experimental cysts, a maximal improvements of noise contrast ratio (CNR) and speckle signals-to-noise ratio (sSNR) is 137% and 114.5% respectively. In general, the proposed methods can effectively address the inherent limitation of the standard CF to improve the speckle quality.

Effects of Pubertal Exposure to Butyl Benzyl Phthalate, Perfluorooctanoic Acid, and Zeranol on Mammary Gland Development and Tumorigenesis in Rats.

Endocrine-disrupting chemicals (EDCs)—including butyl benzyl phthalate (BBP), perfluorooctanoic acid (PFOA), and zeranol (α-ZAL, referred to as ZAL hereafter)—can interfere with the endocrine system and produce adverse effects. It remains unclear whether pubertal exposure to low doses of BBP, PFOA, and ZAL has an impact on breast development and tumorigenesis. We exposed female Sprague Dawley rats to BBP, PFOA, or ZAL through gavage for 21 days, starting on day 21, and analyzed their endocrine organs, serum hormones, mammary glands, and transcriptomic profiles of the mammary glands at days 50 and 100. We also conducted a tumorigenesis study for rats treated with PFOA and ZAL using a 7,12-dimethylbenz[a]anthracene (DMBA) model. Our results demonstrated that pubertal exposure to BBP, PFOA, and ZAL affected endocrine organs and serum hormones, and induced phenotypic and transcriptomic changes. The exposure to PFOA + ZAL induced the most phenotypic and transcriptomic changes in the mammary gland. PFOA + ZAL downregulated the expression of genes related to development at day 50, whereas it upregulated genes associated with tumorigenesis at day 100. PFOA + ZAL exposure also decreased rat mammary tumor latency, reduced the overall survival of rats after DMBA challenge, and affected the histopathology of mammary tumors. Therefore, our study suggests that exposure to low doses of EDCs during the pubertal period could induce changes in the endocrine system and mammary gland development in rats. The inhibition of mammary gland development by PFOA + ZAL might increase the risk of developing mammary tumors through activation of signaling pathways associated with tumorigenesis.

Biochemical and histopathological evaluation of an in vivo model of breast cancer

Though, the clinical management of breast cancer has improved significantly over the past 30 years, it still remains the leading cause of cancer-related female death worldwide. Prevention is the fundamental issue in breast cancer control, for which identification markers in terms of initiation and promotion are necessary. To understand this, an animal model which can recapitulate the early symptoms of breast cancer development and progression is required. Present study is an attempt to develop a convenient and economical in-vivo animal model of breast cancer suitable to conduct such study. Female Wistar and SD rats were injected with different doses and routes of administration of 7, 12-Dihydroxymethylbenz (a) anthracene (DMBA). Animals were observed for the presence of visible/palpable tumours in mammary glands. Various parameters (Tumor morphology, oxidative stress and histopathological studies were studied in different tissues (mammary, lungs, kidney, liver) after the appearance of mammary tumours in rats. After 14 weeks all the animals developed breast carcinomas. The results of this study revealed a significant difference in oxidative stress parameters between DMBA treated and control groups and these alterations were strain dependent. The H&amp;E staining of mice mammary tissue showed development of metaplastic triple negative breast cancer. Immunohistochemistry observation confirmed the triple negative nature of mammary tumours developed in the mice. Data confirmed that DMBA can be used as breast cancer initiator and present model can be further exploited to screen potential anti-breast cancer compounds in vivo.