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International Journal of Molecular... Dec 2020Breast cancer is one of the most frequently diagnosed malignancies and common causes of cancer death in women. Recent studies suggest that environmental exposures to...
Breast cancer is one of the most frequently diagnosed malignancies and common causes of cancer death in women. Recent studies suggest that environmental exposures to certain chemicals, such as 7,12-Dimethylbenzanthracene (DMBA), a chemical present in tobacco, may increase the risk of developing breast cancer later in life. The first-line treatments for breast cancer (surgery, chemotherapy or a combination of both) are generally invasive and frequently associated with severe side effects and high comorbidity. Consequently, novel approaches are strongly required to find more natural-like experimental models that better reflect the tumors' etiology, physiopathology and response to treatments, as well as to find more targeted, efficient and minimally invasive treatments. This study proposes the development and an in deep biological characterization of an experimental model using DMBA-tumor-induction in Sprague-Dawley female rats. Moreover, a photothermal therapy approach using a near-infrared laser coupled with gold nanoparticles was preliminarily assessed. The gold nanoparticles were functionalized with Epidermal Growth Factor, and their physicochemical properties and in vitro effects were characterized. DMBA proved to be a very good and selective inductor of breast cancer, with 100% incidence and inducing an average of 4.7 tumors per animal. Epigenetic analysis showed that tumors classified with worst prognosis were hypomethylated. The tumor-induced rats were then subjected to a preliminary treatment using functionalized gold nanoparticles and its activation by laser (650-900 nm). The treatment outcomes presented very promising alterations in terms of tumor histology, confirming the presence of necrosis in most of the cases. Although this study revealed encouraging results as a breast cancer therapy, it is important to define tumor eligibility and specific efficiency criteria to further assess its application in breast cancer treatment on other species.
Topics: 5-Methylcytosine; 9,10-Dimethyl-1,2-benzanthracene; Animals; Body Weight; Female; Gold; Hyperthermia, Induced; Mammary Neoplasms, Experimental; Metal Nanoparticles; Models, Theoretical; Rats; Rats, Sprague-Dawley
PubMed: 33353068
DOI: 10.3390/ijms21249681 -
Physiological Genomics Feb 2021The p21-activated kinase 1 () gene encodes a serine/threonine kinase that is overexpressed in a subset of human breast carcinomas with poor prognosis. The laboratory rat...
The p21-activated kinase 1 () gene encodes a serine/threonine kinase that is overexpressed in a subset of human breast carcinomas with poor prognosis. The laboratory rat () orthologous gene is located at Mammary carcinoma susceptibility 3 () QTL on rat chromosome . We used quantitative PCR to determine effects of genotype and 7,12-dimethylbenz(a)anthracene (DMBA) exposure on expression. There was no effect of genotype; however, there was a 3.5-fold higher level in DMBA-exposed mammary glands (MGs) than in unexposed glands ( < 0.05). Sequence variants in exons did not alter amino acid sequence between -susceptible and -resistant strains. Protein expression of PAK1/Pak1 in human breast carcinomas and DMBA-exposed rat mammary glands was detected using immunohistochemistry (IHC). Rat mammary glands from 12-wk-old females unexposed to DMBA were negative for Pak1, whereas 24% of carcinogen-exposed mammary glands from age-matched females stained positive for Pak1. The positive mammary glands exposed to carcinogen had no pathological signs of disease. Human breast carcinomas, used as comparative controls, had a 22% positivity rats. This was consistent with other human breast cancer studies of PAK1 expression. Similar frequencies of human/rat PAK1/Pak1 expression in female breast carcinomas and carcinogen-induced rat mammary glands, showing no visible pathogenesis of disease, suggests aberrant expression is an early event in development of some breast cancers. Laboratory rats will be a useful experimental organism for comparative studies of Pak1-mediated mechanisms of breast carcinogenesis. Future studies of PAK1 as a diagnostic marker of early breast disease are warranted.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Breast Neoplasms; Carcinogenesis; Carcinogens; Disease Models, Animal; Female; Humans; Immunohistochemistry; Mammary Glands, Animal; Mammary Neoplasms, Experimental; Rats; Rats, Wistar; p21-Activated Kinases
PubMed: 33346690
DOI: 10.1152/physiolgenomics.00112.2020 -
Bioscience Reports Nov 2020Over the past few years, fabrication of nanoparticles (NPs) has been deployed widely in technologies and many concerns have emerged about the hazardous effect on human...
BACKGROUND
Over the past few years, fabrication of nanoparticles (NPs) has been deployed widely in technologies and many concerns have emerged about the hazardous effect on human health after NPs exposure.
OBJECTIVE
Green synthesis of gold NPs (AuNPs) and assessment of their activity in 7,12-dimethylbenz(a)anthracene (DMBA)-induced breast cancer mouse model.
METHODS
Chloroauric acid (HAuCl4) was used in formation of AuNPs with the help of Curcuma longa as aqueous reducing extract and stabilizing agent at room temperature. Formed NPs were characterized with UV-Vis spectrometry, Fourier-transform infrared spectroscopy (FTIR), Zetasizer measurement, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). Virgin female albino mice with DMBA-induced breast cancer were treated with formed AuNPs for 5 consecutive days and were dissected after 28 days of the beginning of treatment.
RESULTS
UV-Vis spectrometry showed absorbance maximum peak at 530 nm for formed AuNPs, FTIR confirmed formation of plant extract layer around formed NPs; zetasizer measurement revealed 278.2 nm as an average size of produced NPs; SEM and TEM approved formation of monodisperse spherical AuNPs. Biochemical analysis of untreated breast cancer group revealed marked changes in liver and kidney functions manifested by raised activity levels of alanine transaminase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN) and creatinine. Whereas, the treated group with AuNPs post-breast cancer induction displayed reduction in the activities (of ALT, AST and creatinine), while the BUN activity level was raised. Histopathological examination showed heavy incidence of tumor foci in the breast and lymph nodes belonged to the untreated breast cancer group confirmed with intense response to Ki-67 antibodies. While the treated group with AuNPs post-breast cancer induction showed degenerated tumor foci in the breast and lymph nodes with weak response to Ki-67 antibodies.
CONCLUSION
AuNPs were successfully synthesized using HAuCl4 and C. longa extract confirmed their ability to control DMBA-induced breast cancer in virgin female Swiss albino mice.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Alanine Transaminase; Animals; Antineoplastic Agents; Aspartate Aminotransferases; Blood Urea Nitrogen; Breast Neoplasms; Cell Proliferation; Chlorides; Creatinine; Curcuma; Excipients; Female; Gold Compounds; Green Chemistry Technology; Metal Nanoparticles; Mice; Nanomedicine; Neoplasms, Experimental; Oxidation-Reduction; Plant Extracts; Tumor Burden
PubMed: 33165619
DOI: 10.1042/BSR20200115 -
Cancer Prevention Research... Feb 2021Melanocytic nevi are benign proliferations of pigment cells that can occasionally develop into melanomas. There is a significant correlation between increased nevus...
Melanocytic nevi are benign proliferations of pigment cells that can occasionally develop into melanomas. There is a significant correlation between increased nevus numbers and melanoma development. Our previous reports revealed that 7,12-dimethylbenz(a)anthracene (DMBA) and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) induced dysplastic nevi in C3H/HeN mice, with a potential to transform into melanomas. To understand the immune mechanisms behind this transformation, we applied increasing DMBA doses followed by TPA to the skin of C3H/HeN mice. We observed that increased doses of DMBA correlated well with increased numbers of nevi. The increased DMBA dose induced diminished immune responses and promoted the expansion of regulatory T cells (Treg) that resulted in increased IL10 and reduced IFNγ levels. Mice with increased nevus numbers had loss of p16 expression. These mice had increased migration of melanocytic cells to lymph nodes (LN) and a greater percent of LNs produced immortalized melanocytic cell lines. DMBA-induced immunosuppression was lost in CD4-knockout (KO) mice. Lymphocytes in the CD4KO mice produced less IL10 than CD8KO mice. Furthermore, CD4KO mice had significantly reduced nevus numbers and size compared with wild-type and CD8KO mice. These results suggest that Tregs play a vital role in the incidence of nevi and their progression to melanoma. There has been little progress in developing novel strategies for preventing premalignant dysplastic nevi from becoming melanomas. In this study in mice, regulatory-T cells enhanced progression of benign nevi to malignant melanomas; and by inhibiting their activity, melanomas could be retarded. The findings identify new possibilities for melanoma prevention in high risk individuals.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; CD4 Antigens; CD8 Antigens; Female; Humans; Immune Tolerance; Male; Melanoma, Experimental; Mice; Mice, Knockout; Nevus, Pigmented; Skin; Skin Neoplasms; T-Lymphocytes, Regulatory; Tetradecanoylphorbol Acetate
PubMed: 33148679
DOI: 10.1158/1940-6207.CAPR-20-0360 -
Bioscience Reports Sep 2020To investigate the alleviating effects of low-intensity pulsed ultrasound (LIPUS) on myelosuppression of Sprague-Dawley rats with breast cancer induced by...
To investigate the alleviating effects of low-intensity pulsed ultrasound (LIPUS) on myelosuppression of Sprague-Dawley rats with breast cancer induced by cyclophosphamide (CTX). Breast cancer in rats was triggered by intragastric gavage with 7,12-dimethylbenz[a]anthracene (150 mg/kg). Then, the rats with breast cancer were randomly allocated to the LIPUS group (n=50) and the control group (n=50). The LIPUS group was injected intraperitoneally with CTX (50 mg/kg) for 4 consecutive days and underwent LIPUS treatment at femoral metaphysis 20 min per day from the first day of injection for 7 consecutive days. The control group was injected with CTX (50 mg/kg) and treated with LIPUS without energy output. Blood, enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction, Hematoxylin and Eosin (H&E) staining, and scanning electron microscopy were applied to detect the changes. The results indicated that LIPUS significantly promoted the proliferation of bone marrow nucleated cells, white blood cells (WBCs), IgA, IgG, and IgM in the peripheral blood (P<0.05) without the damage to liver and kidney function simultaneously. The mechanisms may result from the LIPUS alleviation effect on bone marrow hematopoietic function through regulating cytokines such as LIPUS can increase the expression of granulocyte colony-stimulating factor (G-CSF), stem cell factor, transforming growth factor-β, and intercellular cell adhesion molecule-1, meanwhile LIPUS will decrease the expression of interleukin-6, tumor necrosis factor-α, and vascular cell adhesion molecule-1. LIPUS has potential to be a new adjuvant therapy method in clinic for ameliorating chemotherapy-induced myelosuppression.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Administration, Oral; Animals; Blood Cell Count; Bone Marrow; Carcinogens; Cyclophosphamide; Disease Models, Animal; Female; Femur; Hematopoiesis; Humans; Injections, Intraperitoneal; Leukopenia; Mammary Neoplasms, Experimental; Rats; Rats, Sprague-Dawley; Ultrasonic Therapy
PubMed: 32936241
DOI: 10.1042/BSR20201350 -
In Vivo (Athens, Greece) 2020Development of malignant tumors is preceded by molecular biological events. Our aim was to establish an assay panel by using miRNAs and other genes for the rapid...
BACKGROUND/AIM
Development of malignant tumors is preceded by molecular biological events. Our aim was to establish an assay panel by using miRNAs and other genes for the rapid screening of potential carcinogens or chemopreventive agents.
MATERIALS AND METHODS
Six male and 6 female CBA/Ca mice received 20 mg/bwkg 7,12-dimethylbenz(α)anthracene (DMBA) intraperitoneally, and 24 h later RNA was isolated from parenchymal organs. Expression of miR-330, miR-29a, miR-9-1, miR-9-3 and mTORC1 was analysed by real time polymerase chain reaction and compared to non-treated controls.
RESULTS
DMBA caused significant alterations in the expression of the studied genes. The most profound changes were the strongly elevated miR-9-3 and mTORC1 expressions in female mice in all organs studied.
CONCLUSION
miR-9-3 and mTORC1 expression in female mice were found to be the most suitable biomarkers for rapid identification of possible carcinogenic effects.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Anthracenes; Carcinogens; Female; Male; Mechanistic Target of Rapamycin Complex 1; Mice; Mice, Inbred CBA; MicroRNAs
PubMed: 32871758
DOI: 10.21873/invivo.12046 -
Carcinogenesis Feb 2021More than a million cases of cutaneous squamous cell carcinoma are diagnosed in the USA each year, and its incidence is increasing. Most of these malignancies arise from...
More than a million cases of cutaneous squamous cell carcinoma are diagnosed in the USA each year, and its incidence is increasing. Most of these malignancies arise from premalignant lesions, providing an opportunity for intervention before malignant progression. We previously documented how cytoplasmic mislocalization of CDC25A in premalignant and malignant skin cancers confers resistance to apoptotic cell death via a mechanism that depends on its interaction with 14-3-3ε. From these data, we hypothesized that 14-3-3ε overexpression drives skin tumor development and progression, such that targeting 14-3-3ε may be a useful strategy for skin cancer treatment. Like CDC25A, 14-3-3ε was overexpressed and mislocalized to the cytoplasm of both benign and malignant human skin cancer. Skin-targeted deletion of the 14-3-3ε gene reduced skin tumor development by 75% and blocked malignant progression. 14-3-3ε suppressed apoptosis through activation of Akt, leading to inhibition of BCL2 associated agonist of cell death and upregulation of Survivin. Using virtual tetrapeptide libraries, we developed a novel peptide that specifically blocked 14-3-3ε heterodimerization and thereby prevented its interaction with CDC25A. The peptide reduced prosurvival signaling, killed skin cancer cells and reduced skin tumor growth in xenograft. Normal skin keratinocytes were unaffected by inhibition or deletion of 14-3-3ε. Thus, targeting of 14-3-3ε dimerization is a promising strategy for the treatment of premalignant skin lesions.
Topics: 14-3-3 Proteins; 9,10-Dimethyl-1,2-benzanthracene; Animals; Antineoplastic Agents; Apoptosis; Carcinogens; Carcinoma, Squamous Cell; Cell Line, Tumor; Cytoplasm; Female; Humans; Keratinocytes; Male; Mice; Mice, Knockout; Neoplasms, Experimental; Protein Multimerization; Skin Neoplasms; Tetradecanoylphorbol Acetate; Xenograft Model Antitumor Assays; cdc25 Phosphatases
PubMed: 32816038
DOI: 10.1093/carcin/bgaa091 -
The Journal of Investigative Dermatology Apr 2021Integrin α3β1 plays a crucial role in tumor formation in the two-stage chemical carcinogenesis model (DMBA and TPA treatment). However, the mechanisms whereby the...
Integrin α3β1 plays a crucial role in tumor formation in the two-stage chemical carcinogenesis model (DMBA and TPA treatment). However, the mechanisms whereby the expression of α3β1 influences key oncogenic drivers of this established model are not known yet. Using an in vivo mouse model with epidermal deletion of α3β1 and in vitro Matrigel cultures of transformed keratinocytes, we demonstrate the central role of α3β1 in promoting the activation of several protumorigenic signaling pathways during the initiation of DMBA/TPA‒driven tumorigenesis. In transformed keratinocytes, α3β1-mediated focal adhesion kinase/Src activation leads to in vitro growth of spheroids and to strong Akt and STAT 3 activation when the α3β1-binding partner tetraspanin CD151 is present to stabilize cell‒cell adhesion and promote Smad2 phosphorylation. Remarkably, α3β1 and CD151 can support Akt and STAT 3 activity independently of α3β1 ligation by laminin-332 and as such control the essential survival signals required for suprabasal keratin-10 expression during keratinocyte differentiation. These data demonstrate that α3β1 together with CD151 regulate the signaling pathways that control the survival of differentiating keratinocytes and provide a mechanistic understanding of the essential role of α3β1 in early stages of skin cancer development.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Carcinogens; Cell Adhesion; Cell Adhesion Molecules; Cell Line; Cell Survival; Cell Transformation, Neoplastic; Epidermis; Humans; Integrin alpha3beta1; Keratinocytes; Mice; Neoplasms, Experimental; Signal Transduction; Skin Neoplasms; Spheroids, Cellular; Tetradecanoylphorbol Acetate; Tetraspanin 24; Kalinin
PubMed: 32805217
DOI: 10.1016/j.jid.2020.07.024 -
Nutrients Jul 2020Natural products have attracted great interest for some time as alternative methods against cancers by fulfilling immunomodulating properties. In this study, we...
Natural products have attracted great interest for some time as alternative methods against cancers by fulfilling immunomodulating properties. In this study, we investigated the activity of hot water extracts (120 °C, >30 min) of fresh leaves of Kumaizasa bamboo and Chaga mushroom which we called MeshimaMax, for cancer prevention and treatment by using different solid tumor models. In the implanted mouse sarcoma S180 tumor, MeshimaMax treatment significantly inhibited tumor growth when it was applied at the early stage of tumor inoculation. The effect was further confirmed by using carcinogen induced tumors, i.e., azoxymethane (AOM)/dextran sulfate sodium (DSS) induced mouse colon cancer and 7,12-dimethylbenz anthracene (DMBA) induced rat breast cancer. In both cases the occurrences of tumors were remarkably suppressed by administration of MeshimaMax which consists of three components above. More importantly, when MeshimaMax was combined with an anticancer chemotherapeutic drug, the therapeutic effect was remarkably improved. In vitro studies showed that when MeshimaMax was applied to mouse macrophage RAW264.7 cells the phagocytosis of macrophages was significantly activated, which was evaluated by using living yeast cells as well as synthetic nanoparticles. A cytotoxicity assay showed the 50% inhibitory concentration (IC) was higher than 1 mg/mL and normal cells were 2-3 times more tolerant to MeshimaMax than cancer cells. These findings suggest the potential application of MeshimaMax for cancer prevention and as supplement regimen for anticancer chemotherapy, probably functioning through activation of innate immunity, which may benefit cancer patients as an alternative supplement.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Antineoplastic Combined Chemotherapy Protocols; Azoxymethane; Breast Neoplasms; Colonic Neoplasms; Dextran Sulfate; Disease Models, Animal; Female; Immunity, Innate; Inonotus; Macrophages; Male; Mice; Phagocytosis; Phellinus; Plant Extracts; Plant Leaves; RAW 264.7 Cells; Rats; Sarcoma 180; Sasa
PubMed: 32751371
DOI: 10.3390/nu12082279 -
Nature Communications Jul 2020Hormone receptor (HR) breast cancer (BC) causes most BC-related deaths, calling for improved therapeutic approaches. Despite expectations, immune checkpoint blockers...
Hormone receptor (HR) breast cancer (BC) causes most BC-related deaths, calling for improved therapeutic approaches. Despite expectations, immune checkpoint blockers (ICBs) are poorly active in patients with HR BC, in part reflecting the lack of preclinical models that recapitulate disease progression in immunocompetent hosts. We demonstrate that mammary tumors driven by medroxyprogesterone acetate (M) and 7,12-dimethylbenz[a]anthracene (D) recapitulate several key features of human luminal B HRHER2 BC, including limited immune infiltration and poor sensitivity to ICBs. M/D-driven oncogenesis is accelerated by immune defects, demonstrating that M/D-driven tumors are under immunosurveillance. Safe nutritional measures including nicotinamide (NAM) supplementation efficiently delay M/D-driven oncogenesis by reactivating immunosurveillance. NAM also mediates immunotherapeutic effects against established M/D-driven and transplantable BC, largely reflecting increased type I interferon secretion by malignant cells and direct stimulation of immune effector cells. Our findings identify NAM as a potential strategy for the prevention and treatment of HR BC.
Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Breast Neoplasms; Carcinogenesis; Disease Progression; Female; Humans; Immunotherapy; Interferon Type I; Mammary Neoplasms, Experimental; Medroxyprogesterone Acetate; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Niacinamide; Receptor, ErbB-2; Survival Analysis
PubMed: 32732875
DOI: 10.1038/s41467-020-17644-0