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1.
Cell Death Dis ; 15(4): 247, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38575576

RESUMO

The primary site of metastasis for epithelial ovarian cancer (EOC) is the peritoneum, and it occurs through a multistep process that begins with adhesive contacts between cancer cells and mesothelial cells. Despite evidence that Notch signaling has a role in ovarian cancer, it is unclear how exactly it contributes to ovarian cancer omental metastasis, as well as the cellular dynamics and intrinsic pathways that drive this tropism. Here we show that tumor cells produced the Notch ligand Jagged2 is a clinically and functionally critical mediator of ovarian cancer omental metastasis by activating the Notch signaling in single-layered omental mesothelial cells. In turn, Jagged2 promotes tumor growth and therapeutic resistance by stimulating IL-6 release from mesothelial cells. Additionally, Jagged2 is a potent downstream mediator of the omental metastasis cytokine TGF-ß that is released during omental destruction. Importantly, therapeutic inhibition of Jagged2-mediated omental metastasis was significantly improved by directly disrupting the Notch pathway in omental mesothelial cells. These findings highlight the key role of Jagged2 to the functional interplay between the TGF-ß and the Notch signaling pathways during the metastatic process of ovarian cancer cells to the omentum and identify the Notch signaling molecule as a precision therapeutic target for ovarian cancer metastasis.


Assuntos
Neoplasias Ovarianas , Neoplasias Peritoneais , Neoplasias Retroperitoneais , Feminino , Humanos , Carcinoma Epitelial do Ovário , Linhagem Celular Tumoral , Metástase Neoplásica , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/secundário , Transdução de Sinais , Fator de Crescimento Transformador beta/metabolismo
2.
Cells ; 13(8)2024 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-38667295

RESUMO

Decorin (DCN), a member of the small leucine-rich proteoglycan gene family, is secreted from stromal fibroblasts with non-cell-autonomous anti-breast-cancer effects. Therefore, in the present study, we sought to elucidate the function of decorin in breast stromal fibroblasts (BSFs). We first showed DCN downregulation in active cancer-associated fibroblasts (CAFs) compared to their adjacent tumor counterpart fibroblasts at both the mRNA and protein levels. Interestingly, breast cancer cells and the recombinant IL-6 protein, both known to activate fibroblasts in vitro, downregulated DCN in BSFs. Moreover, specific DCN knockdown in breast fibroblasts modulated the expression/secretion of several CAF biomarkers and cancer-promoting proteins (α-SMA, FAP- α, SDF-1 and IL-6) and enhanced the invasion/proliferation abilities of these cells through activation of the STAT3/AUF1 signaling. Furthermore, DCN-deficient fibroblasts promoted the epithelial-to-mesenchymal transition and stemness processes in BC cells in a paracrine manner, which increased their resistance to cisplatin. These DCN-deficient fibroblasts also enhanced angiogenesis and orthotopic tumor growth in mice in a paracrine manner. On the other hand, ectopic expression of DCN in CAFs suppressed their active features and their paracrine pro-carcinogenic effects. Together, the present findings indicate that endogenous DCN suppresses the pro-carcinogenic and pro-metastatic effects of breast stromal fibroblasts.


Assuntos
Neoplasias da Mama , Fibroblastos Associados a Câncer , Decorina , Regulação para Baixo , Interleucina-6 , Fator de Transcrição STAT3 , Transdução de Sinais , Decorina/metabolismo , Decorina/genética , Humanos , Fator de Transcrição STAT3/metabolismo , Feminino , Interleucina-6/metabolismo , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Neoplasias da Mama/genética , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Regulação para Baixo/genética , Ribonucleoproteína Nuclear Heterogênea D0/metabolismo , Fibroblastos/metabolismo , Células Estromais/metabolismo , Linhagem Celular Tumoral , Carcinogênese/patologia , Carcinogênese/genética , Carcinogênese/metabolismo , Proliferação de Células , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Mama/patologia , Mama/metabolismo
3.
Transl Oncol ; 37: 101780, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37672859

RESUMO

BACKGROUND: Radiotherapy is an important therapeutic strategy for breast cancer patients through reducing the chances of recurrence and metastasis, which are fueled by cancer-associated fibroblasts (CAFs). Thereby, we addressed here the effect of various doses of X-rays on breast CAFs and their adjacent counterparts. METHODS: We have used WST1 and annexin V-associated with flow cytometry to test the cytotoxic effects of X-rays. Immunoblotting and ELISA was used to assess the expression/secretion of various proteins. Immunohistochemistry was utilized to determine the level of ß-galactosidase and Ki-67. Sphere formation assay was used to test the ability of breast cancer cells to form tumorspheres. Orthotopic tumor xenografts were also used to evaluate the effect of X-ray-treated breast stromal fibroblasts on breast cancer tumor growth in vivo. RESULTS: Breast stromal fibroblasts showed high resistance to X-rays. While the low dose (5 Gy) inhibited cell proliferation and the active features of CAFs, the higher doses (16 and 50 Gy) promoted senescence. However, this was not accompanied by the senescence-associated secretory phenotype (SASP), but rather a reduction in the synthesis/secretion of various cancer-associated cytokines. Additionally, X-rays suppressed the features of active breast stromal fibroblasts, and their paracrine pro-carcinogenic effects. The ablative dose (16 Gy) inhibited the capacity of active stromal fibroblasts to promote the pro-metastatic processes epithelial-to-mesenchymal transition, the formation of cancer stem cells, as well as the growth of humanized orthotopic breast tumor xenografts. CONCLUSION: Together, these findings indicate that X-rays can normalize the features of active breast stromal fibroblasts through promoting senescence without SASP.

4.
J Opt Soc Am A Opt Image Sci Vis ; 40(8): 1563-1567, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37707112

RESUMO

It is well known that in free space propagations, Bessel-Gauss (BG) beams are non-diffractive, in the sense that over a finite distance the beam mainlobe does not spread. Non-diffraction beams have been found to offer advantages over diffractive beams, for example, in terms of power delivery. However, in random media, such as a turbulent atmosphere, the performance of BG beams is still an active area of research. For example, applying the extended Huygens-Fresnel (EHF) principle results in an intractable expression for the optical field and the average intensity. This work is concerned with finding a closed-form expression for the average intensity of BG beam propagating through weak and strong Kolmogorov turbulence under the quadratic structure function (QSF) assumption. This is achieved by considering the average intensity convolution integral of the free space intensity with the point spread function (PSF). This convolution integral is reduced to a one-dimensional integral that can be easily evaluated in closed form and plotted. Moreover, the beam root mean square (rms) width is also given in terms of one-dimensional integrals. The work presented can be used for assessing the utility of a BG beam for applications in emerging communication systems such as optical wireless communications (OWC).

5.
Cureus ; 15(7): e42002, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37593274

RESUMO

OBJECTIVE: Experimental animal liver transplantation is the initial step, before the application of the procedure on humans. Canine and swine transplantation were used to perfect the technical aspects of the procedure. Small animals such as rats were mainly utilized to study the metabolic and immunological aspects of liver transplantation. In this paper, we describe our experience with attempting liver transplantation in a sheep animal model. MATERIAL AND METHOD: The animal model used for both donor and recipient was outbred male weanling sheep of Naimi strain (Ovis aries, Awassi). They weigh between 25 and 35 kg. They were put under general anesthesia. Harvested livers were kept in cold storage. Recipients underwent hepatectomy, after construction of an active portal systemic bypass using a Medtronic pump. The implantation was done with caval replacement and direct portal anastomosis. The hepatic artery with its attachments to the aortal was anastomosed directly to the recipient aorta. RESULT: Twelve pairs (24 sheep) were utilized for donor and recipient surgery. Donor surgery was completed successfully in all 12 cases. Recipient surgery was not completed in three cases, when animals were lost in the implantation phase, before reperfusion mainly due to uncontrolled bleeding, resulting in hemodynamic instability. We also lost five recipients immediately after reperfusion, mainly due to post-perfusion bleeding and hemodynamic instability. Four recipients stayed alive after the implantation. CONCLUSION: We demonstrated the feasibility of using sheep as an animal model for liver transplantation. We described the similarities of sheep liver to that of humans, as well as the technical difficulties. This model is suitable in situations where other well-established models are not available for cultural or religious reasons. Further refinement in the technical aspects will be needed, as well as investigation of the biochemical outcome and long-term survival.

6.
J Fr Ophtalmol ; 46(3): 266-275, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36801112

RESUMO

PURPOSE: To report the relative efficacy of combining phacoemulsification with a Schlemm's canal microstent (Phaco/Hydrus) or dual blade trabecular excision (Phaco/KDB). DESIGN: Retrospective study. METHODS: One hundred and thirty-one eyes of 131 patients who underwent Phaco/Hydrus or Phaco/KDB procedures from January 2016 to July 2021 at a tertiary care center were included and assessed for up to 36months postoperatively. Primary outcomes were intraocular pressure (IOP) and number of glaucoma medications, evaluated by generalized estimating equations (GEE). Two Kaplan-Meier estimates (KM) assessed survival without additional intervention or pressure lowering medication while maintaining: (1) IOP≤21mmHg and≥20% IOP reduction or (2) IOP≤preoperatively designated goal. RESULTS: Mean preoperative IOP was 17.70±4.91 (SD) mmHg on 0.28±0.86 medications in the Phaco/Hydrus cohort (n=69) and 15.92±4.34mmHg on 0.19±0.70 medications in the Phaco/KDB cohort (n=62). At 12months, mean IOP was reduced to 14.98±2.77mmHg on 0.12±0.60 medications after Phaco/Hydrus and 13.52±4.13mmHg on 0.04±0.19 medications after Phaco/KDB. GEE models of IOP (P<0.001) and medication burden (P<0.05) showed significant patterns of reduction across all timepoints in both cohorts. There were no differences in IOP reduction (P=0.94), number of medications (P=0.95) or survival (P=0.72 by KM1, P=0.11 by KM2) between procedures. CONCLUSIONS: Both Phaco/Hydrus and Phaco/KDB resulted in significantly reduced IOP and medication burden for over 12months. Phaco/Hydrus and Phaco/KDB confer similar outcomes in terms of IOP, medication burden, survival, and procedural time in a population with predominantly mild and moderate open-angle glaucoma.


Assuntos
Glaucoma de Ângulo Aberto , Glaucoma , Hipotensão Ocular , Facoemulsificação , Trabeculectomia , Humanos , Facoemulsificação/efeitos adversos , Facoemulsificação/métodos , Glaucoma de Ângulo Aberto/complicações , Glaucoma de Ângulo Aberto/cirurgia , Estudos Retrospectivos , Canal de Schlemm , Trabeculectomia/métodos , Glaucoma/complicações , Glaucoma/cirurgia , Pressão Intraocular , Hipotensão Ocular/cirurgia
7.
J Opt Soc Am A Opt Image Sci Vis ; 40(1): 53-63, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36607075

RESUMO

A model for the received irradiance statistical distribution for turbulence induced fading channels is derived. The derivation is based on expanding the extended Rytov method by associating a doubly stochastic process to model large scale scintillation. In particular, the large scale induced fluctuations are modeled as the product of arbitrary numbers of gamma and inverse gamma random variables, while the small scale induced irradiance fluctuations are modeled as a single gamma random variable. Closed form expressions for the probability density function (pdf), cumulative distributions, and moment generating function are given. Also, a procedure is proposed for associating the pdf parameters with the large and small scale induced variances. The proposed model is seen to contain many previously published models, such as gamma-gamma (GG) and Fischer-Snedicor F, as special cases. Moreover, two new fading distributions are introduced and analyzed, and plots for the proposed pdfs are generated and compared with often used models and measurements, thus showing the accuracies of the derived models.

8.
Nat Prod Res ; 37(24): 4112-4120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36661202

RESUMO

The objective of the current study was to extract 2-(benzhydryl sulfinyl)-N-sec-butylacetamide), a novel compound from fig, and then determine its role in enhancing trastuzumab-triggered phagocytic killing of SKOV-3 cancer cells. In this study, Soxhlet was used to extract the compound from the mature and air-dried fig fruits. The production of the isolated extracts was enhanced by using polar and non-polar solvents. Several solvents, such as methanol, ethyl acetate, chloroform, and n-hexane, were used to isolate the effective compound 2-(benzhydryl sulfinyl)-N-sec-butylacetamide) from the organic layer. UV-spectroscopy, FT-IR, 1H-NMR, and 13C-NMR were applied to identify the purified compound. The in vitro and in vivo assays demonstrated that the 2-(benzhydryl sulfinyl)-N-sec-butylacetamide) can increase the activity of the phagocytic cells, via the interaction with FcY receptors, along with trastuzumab, and the pathway can use a model for the therapeutic strategy for effective treatment of ovarian cancer cells.


Assuntos
Ficus , Neoplasias , Trastuzumab/farmacologia , Receptores de IgG , Espectroscopia de Infravermelho com Transformada de Fourier , Extratos Vegetais/química , Fagócitos , Solventes
9.
J Opt Soc Am A Opt Image Sci Vis ; 39(7): 1267-1274, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-36215612

RESUMO

A model for the irradiance probability density function for turbulence induced fading in free space optical communications is derived. The derivations are based on expanding on the extended Rytov method by associating a doubly stochastic process to model large scale scintillation. In particular, the small scale induced irradiance fluctuations are modeled by a single gamma distribution, while the large scale induced fluctuations are modeled as a doubly stochastic process of gamma and inverted gamma distributions, thus better approximating the lognormal distribution. The resultant distribution's probability density and cumulative density functions are both given in closed forms. Moreover, the resultant model parameters are given based on strong scintillation theory. Through comparison with previously published results and experimental data, including lognormal and gamma-gamma distributions, it is concluded that the proposed model agrees well with measurements for weak and strong scintillation conditions in cases of both aperture averaging and a point like receiver. Therefore, the proposed model can be used for the performance analysis of optical wireless systems.

10.
Saudi Med J ; 42(12): 1289-1295, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34853133

RESUMO

OBJECTIVES: To describe a novel animal model for ex-vivo liver perfusion. METHODS: This study was carried out at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia, between September 2016 and January 2019. We assembled a perfusion circuit operated by a continuous pressure-driven arterial pump with continuous portal and arterial pressure and volume measurements. We used normothermic oxygenated perfusate. The livers used were retrieved from the sheep. RESULTS: Ex-vivo continuous perfusion of the liver was achieved for up to 9 hours with stable pressure and volume in both hepatic artery and portal vein. In 4 experiments the arterial pressure was kept in a range of 48-52 mmHg with a mean of 51.75±4.31 resulting in arterial volume at steady state of 223.5±48.25 ml/minute (95% confidence level). At steady state the mean portal pressure was 16.25±1.45 mmHg with a mean volume of 854±313.75 ml/minute (95% confidence level). Bile production was observed during the perfusion period. Hemodynamic parameters were similar to the physiological parameters observed in normothermic perfusion model of the porcine liver. CONCLUSION: A normothermic oxygenated ex-vivo perfusion circuit was successfully constructed using the sheep liver. A sustainable functional circuit with physiological hemodynamic parameters was achieved. Further study on sheep model seems to be feasible.


Assuntos
Transplante de Fígado , Animais , Fígado , Perfusão , Arábia Saudita , Ovinos , Suínos
11.
Carcinogenesis ; 42(12): 1439-1448, 2021 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-34718441

RESUMO

Active breast cancer-associated fibroblasts (CAFs), the most influential cells in breast tumor microenvironment, express/secrete high levels of the proinvasive/metastatic interleukin-6 (IL-6). Therefore, we have tested here the effect of the IL-6 receptor (IL-6R) inhibitor tocilizumab (TCZ; Actemra) on different active breast CAFs. We have shown that TCZ potently and persistently suppresses the expression of various CAF biomarkers, namely α-SMA, SDF-1 as well as the STAT3 pathway and its downstream target AUF1. TCZ also inhibited the proliferation, migration and invasion abilities of active breast CAF cells. Additionally, TCZ repressed the ability of CAF cells in promoting epithelial-to-mesenchymal transition, and enhancing the migratory/invasive and proliferative capacities of breast cancer cells in vitro. Importantly, these findings were confirmed in orthotopic humanized breast tumors in mice. Furthermore, TCZ suppressed the expression of the pro-angiogenic factor VEGF-A and its transactivator HIF-1α in CAF cells, and consequently inhibited the angiogenic-promoting effect of active CAFs both in vitro and in orthotopic tumor xenografts. These results indicate that inhibition of the IL-6/STAT3/AUF1 pathway by TCZ can normalize active breast CAFs and suppress their paracrine pro-carcinogenic effects, which paves the way toward development of specific CAF-targeting therapy, badly needed for more efficient breast cancer treatments.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos Imunológicos/farmacologia , Fibroblastos Associados a Câncer/efeitos dos fármacos , Fibroblastos Associados a Câncer/metabolismo , Ribonucleoproteína Nuclear Heterogênea D0/metabolismo , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Fibroblastos Associados a Câncer/patologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Ribonucleoproteína Nuclear Heterogênea D0/genética , Humanos , Interleucina-6/metabolismo , Receptores de Interleucina-6/antagonistas & inibidores , Microambiente Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Carbohydr Polym ; 273: 118589, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34560990

RESUMO

Nowadays, vascularization and mineralization of bone defects is the main bottleneck in the bone regeneration field that is needed to be overcome and developed. Here, we prepared novel in-situ formed injectable hydrogels based on chitosan biguanidine and carboxymethylcellulose loaded with vascular endothelial growth factor (VEGF) and recombinant Bone morphogenetic protein 2 (BMP-2) and studied its influence on osteoblastic differentiation of dental pulp stem cells (DPSCs). The sequential release behavior of the VEGF and BMP-2 from hydrogels adjusted with the pattern of normal human bone growth. MTT assay exhibited that these hydrogels were non-toxic and significantly increased DPSCs proliferation. The Real-time PCR and Western blot analysis on CG11/BMP2-VEGF showed significantly higher gene and protein expression of ALP, COL1α1, and OCN. These results were confirmed by mineralization assay by Alizarin Red staining and Alkaline phosphatase enzyme activity. Based on these evaluations, these hydrogel holds potential as an injectable bone tissue engineering platform.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Portadores de Fármacos/química , Hidrogéis/química , Osteogênese/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Fator A de Crescimento do Endotélio Vascular/farmacologia , Proteína Morfogenética Óssea 2/química , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quitosana/análogos & derivados , Quitosana/toxicidade , Polpa Dentária/citologia , Portadores de Fármacos/toxicidade , Liberação Controlada de Fármacos , Guanidinas/química , Guanidinas/toxicidade , Humanos , Hidrogéis/toxicidade , Osteoblastos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/farmacologia , Resistência à Tração , Alicerces Teciduais/química , Fator de Crescimento Transformador beta/química , Fator A de Crescimento do Endotélio Vascular/química
13.
Cancer Lett ; 520: 374-384, 2021 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-34416336

RESUMO

Normal breast fibroblasts (NBFs) support and maintain the architecture of the organ, and can also suppress tumorigenesis. However, the mechanisms involved are not fully understood. We have shown here that NBFs suppress breast carcinogenesis through secretion of osteoprotegerin (OPG), a soluble decoy receptor for the Receptor Activator of NF-κB ligand (RANKL). Indeed, NBFs and human recombinant OPG (rOPG), suppressed breast cancer cells proliferation and motility through inhibition of the epithelial-to-mesenchymal transition (EMT) process both in vitro and in vivo. Additionally, rOPG inhibited the IL-6/STAT3 and NF-κB pathways as well as the OPG gene, which turned out to be STAT3-regulated. This was confirmed using denosumab, a RANKL-targeted antibody, which also inhibited NF-κB, down-regulated OPG and repressed EMT in breast cancer cells grown in 2D and 3D. Importantly, both rOPG and denosumab targeted cancer stem cells (CSCs). This was mediated through inhibition of the CSC-related pathway ß-catenin. Moreover, rOPG reduced tumor growth and inhibited breast CSC biomarkers in orthotopic humanized breast tumors. Therefore, normal mammary fibroblasts can suppress carcinogenesis through OPG, which constitutes great potential as preventive and/or therapeutic molecule for breast carcinomas.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Osteoprotegerina/genética , Ligante RANK/genética , Proteínas Recombinantes/genética , beta Catenina/genética , Anticorpos/farmacologia , Anticarcinógenos/farmacologia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinogênese/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Denosumab/farmacologia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Feminino , Fibroblastos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/genética , NF-kappa B/antagonistas & inibidores , NF-kappa B/genética , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/patologia , Osteoprotegerina/imunologia , Osteoprotegerina/farmacologia , Ligante RANK/antagonistas & inibidores , Proteínas Recombinantes/farmacologia , Fator de Transcrição STAT3/genética
14.
Oncogenesis ; 9(8): 70, 2020 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-32759946

RESUMO

The AU-rich element RNA-binding protein 1 (AUF1) is an RNA-binding protein, which can both stabilize and destabilize the transcripts of several cancer-related genes. Since epithelial-to-mesenchymal transition (EMT) and the acquisition of cancer stem cell traits are important for cancer onset and progression, we sought to determine the role of AUF1 in these two important processes. We have shown that AUF1 induces EMT and stemness in breast epithelial cells via stabilization of the SNAIL1 and TWIST1 mRNAs, and their consequent upregulation. Indeed, AUF1 binds the transcripts of these two genes at their 3'UTR and reduces their turnover. Ectopic expression of AUF1 also promoted stemness in mammary epithelial cells, and thereby increased the proportion of cancer stem cells. Importantly, breast cancer cells that ectopically express AUF1 were more efficient in forming orthotopic tumor xenografts in nude mice than their corresponding controls with limiting cell inocula. On the other hand, AUF1 downregulation with specific siRNA inhibited EMT and reduced the stemness features in breast cancer cells. Moreover, AUF1 knockdown sensitized breast cancer cells to the killing effect of cisplatin. Together, these findings provide clear evidence that AUF1 is an important inducer of the EMT process through stabilization of SNAIL1 and TWIST1 and the consequent promotion of breast cancer stem cells. Thereby, AUF1 targeted molecules could constitute efficient therapeutics for breast cancer patients.

15.
Mol Carcinog ; 59(9): 1041-1051, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32537818

RESUMO

Triple-negative breast cancer (TNBC) is a very aggressive subtype with high recurrence rate and no molecular targets for therapies. This subtype is characterized by high expression/secretion of the proinvasive/metastatic interleukin-6 (IL-6) cytokine. In the present study, we have shown that tocilizumab inhibits the IL-6/STAT3 signaling and suppresses the cancer/inflammatory epigenetic IL-6/STAT3/NF-κB positive feedback loop. Furthermore, tocilizumab inhibited the proliferative and the migratory/invasiveness capacities as well as the epithelial-to-mesenchymal transition (EMT) process in TNBC cells. Importantly, tocilizumab suppressed the stemness-related characteristics of TNBC cells, through the inhibition of the Wnt/ß-catenin breast cancer stem cell-related pathway. Additionally, we have shown that tocilizumab suppresses the paracrine activation of normal breast stromal fibroblasts to myofibroblats. Moreover, tocilizumab sensitized TNBC cells to the cytotoxic effect of cisplatin in vitro. Furthermore, pharmacological inhibition of IL-6 by tocilizumab had great inhibitory effect on tumor growth and the EMT process in humanized orthotopic breast tumors in mice. In addition, tocilizumab potentiated the proapoptotic effect of cisplatin in humanized breast tumors. Together, these findings indicate that tocilizumab can suppress the prometastatic capacity of TNBC cells and enhances the cytotoxic effect of cisplatin against these cells. Therefore, tocilizumab could be of great therapeutic value for these hard-to-treat TNBC patients.


Assuntos
Anticorpos Monoclonais Humanizados/farmacologia , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Sinergismo Farmacológico , Transição Epitelial-Mesenquimal , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Animais , Apoptose , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Movimento Celular , Proliferação de Células , Feminino , Humanos , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , NF-kappa B/genética , NF-kappa B/metabolismo , Invasividade Neoplásica , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Neoplasias de Mama Triplo Negativas/patologia , Células Tumorais Cultivadas , Proteína Wnt1/genética , Proteína Wnt1/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética , beta Catenina/metabolismo
16.
Materials (Basel) ; 13(10)2020 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-32443661

RESUMO

Carbon nanotubes (CNTs) are synthesized by the flame fragment deposition (FFD) technique using Iraqi liquefied petroleum gas (LPG) as a source of carbon in a hand-made reactor at a low temperature (160 °C) without using a catalyst. Purification of the multi-walled carbon nanotubes (MWCNTs) is carried out using a two-step process consisting of sonication in 30 wt.% hydrogen peroxide (H2O2) solution at room temperature to remove amorphous impurities adhering to the walls of the CNTs and carbon nanoparticles (CNPs), followed by sonication in an acetone bath to remove the polyaromatic hydrocarbons (PAH) formed during the LPG gas burning. Comprehensive characterizations such as X-ray diffraction (XRD), atomic force microscopy (AFM), thermo-gravimetric analysis (TGA), and transmission electron microscopy (TEM) were conducted to verify the efficiency of the purification process. The results clearly demonstrated that this process is promising for the purification of the synthesized CNTs.

17.
Appl Opt ; 59(9): 2759-2766, 2020 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-32225825

RESUMO

This work examined adaptive optical prisms by using a ladder-plus-Y double quantum dot system. A good dispersion angle and high spectral angular dispersion are obtained under the application of two optical fields (pump and probe) or three optical fields where an additional optical field between quantum-dot-wetting layer states is applied. These good results are obtained at a wide window of electromagnetically induced transparency with zero susceptibility.

18.
Vet World ; 12(7): 1013-1021, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31528026

RESUMO

AIM: This study aimed to evaluate the protective effect of edible bird's nest (EBN) supplement on the uteri of rats exposed to lead acetate (LA) toxicity. MATERIALS AND METHODS: Five treatment groups were established as follows: Group 1 (C), which was given distilled water; Group 2 (T0), which was administered with LA (10 mg/kg body weight [BW]); and Groups 3 (T1), 4 (T2), and 5 (T3), which were given LA (10 mg/kg BW) plus graded concentrations of 30, 60, and 120 mg/kg BW of EBN, respectively. Rats were euthanized at week 5 to collect blood for superoxide dismutase (SOD) assay, and uterus for histomorphological study and expression analyses of epidermal growth factor (EGF), vascular endothelial growth factor (VEGF), and proliferating cell nuclear antigen (PCNA). RESULTS: Results revealed that LA causes destruction of uterine lining cells and necrosis of uterine glands of exposed rats without EBN supplement while the degree of damage decreased among EBN treated groups; T3 showed the highest ameliorating effect against LA toxicity, as well as an increased number of uterine glands. Increased levels of SOD were also achieved in EBN supplemented groups than the controls. Results of immunohistochemistry showed significantly higher expressions of EGF, VEGF, and PCNA levels (p<0.05) in T3 compared to other treatments. EBN maintained upregulation of antioxidant - reactive oxygen species balance. CONCLUSION: The findings showed that EBN could ameliorate the detrimental effects of LA toxicity on the uterus possibly by enhancing enzymatic antioxidant (SOD) activity as well as expressions of EGF, VEGF, and PCNA with cell proliferation roles.

19.
Oncotarget ; 9(2): 2329-2343, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29416775

RESUMO

The activation of breast stromal fibroblasts is a crucial step toward tumor growth and spread. Therefore, it is extremely important to understand the molecular basis of this activation and determine the molecules and the mechanisms responsible for its sustainability. In the present report we have shown that the DNA methyl-transferase protein DNMT1 is critical for the activation of breast stromal fibroblasts as well as the persistence of their active status. Indeed, we have first revealed DNMT1 up-regulation in most cancer-associated fibroblasts relative to their corresponding adjacent normal fibroblasts. This effect resulted from HuR-dependent stabilization of the DNMT1 mRNA. Furthermore, ectopic expression of DNMT1 activated primary normal breast fibroblasts and promoted their pro-carcinogenic effects, both in vitro and in orthotopic tumor xenografts. By contrast, specific DNMT1 knockdown normalized breast myofibroblasts and repressed their cancer-promoting properties. These effects were sustained through inhibition of the IL-6/STAT3/NF-κB epigenetic cancer/inflammation positive feedback loop. Furthermore, we have shown that DNMT1-related activation of breast fibroblasts is mediated through upregulation of the RNA binding protein AUF1, which is also part of the loop. The present data demonstrate the critical function of DNMT1 in breast cancer-related sustained activation of breast stromal fibroblasts.

20.
Cryobiology ; 80: 43-50, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29269043

RESUMO

This study aims to assess the effect of Eurycoma longifolia aqueous extract on chilled and cryopreserved quality of bull sperm. Semen samples were obtained from four Simmental-Brangus. Each sample was divided into two fractions: the first fraction was used for chilling the semen, and the second fraction was used for the freezing process. Both fractions were extended with Tris-egg yolk extender supplemented with 0.0, 0.25, 0.5, 1.0, 2.5, 5.0, and 7.5 mg/ml Eurycoma longifolia aqueous extract. The diluted chilled fraction was chilled at 5 °C for 6 days, whereas the frozen-thawed fraction was frozen in liquid nitrogen. Data revealed that 1 mg/ml E. longifolia aqueous extract yielded significantly (p < .05) higher sperm motility, morphology, viability, and sperm membrane integrity compared with the control group and other treated groups in chilled semen evaluation. For cryopreserved sperm, a significant difference (p < .05) in sperm motility, viability, sperm membrane integrity, DNA integrity, and lipid peroxidation was observed between 5 mg/ml E. longifolia aqueous extract and other treated and control groups. However, no significant difference in the percentage of sperm exhibiting normal sperm morphology was observed among the groups. In conclusion, the addition of 0.25 and 1 mg/ml E. langifolia extract to chilled semen and 5 mg/ml E. longifolia aqueous extract to cryopreserved sperm into Tris-egg yolk extender helps in maintaining superior quality of bull spermatozoa during chilling and freezing.


Assuntos
Criopreservação/métodos , Crioprotetores/farmacologia , Eurycoma , Extratos Vegetais/farmacologia , Preservação do Sêmen/métodos , Animais , Bovinos , Criopreservação/veterinária , DNA/efeitos dos fármacos , Gema de Ovo , Congelamento , Peroxidação de Lipídeos/efeitos dos fármacos , Masculino , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Espermatozoides/fisiologia , Trometamina
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