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1.
Semin Cancer Biol ; 86(Pt 3): 743-752, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-34273519

RESUMEN

The role of human microbiota in cancer initiation and progression is recognized in recent years. In order to investigate the interactions between cancer cells and microbes, a systematic analysis using various emerging techniques is required. Owing to the label-free, non-invasive and molecular fingerprinting characteristics, vibrational spectroscopy is uniquely suited to decode and understand the relationship and interactions between cancer and the microbiota at the molecular level. In this review, we first provide a quick overview of the fundamentals of vibrational spectroscopic techniques, namely Raman and infrared spectroscopy. Next, we discuss the emerging evidence underscoring utilities of these spectroscopic techniques to study cancer or microbes separately, and share our perspective on how vibrational spectroscopy can be employed at the intersection of the two fields. Finally, we envision the potential opportunities in exploiting vibrational spectroscopy not only in basic cancer-microbiome research but also in its clinical translation, and discuss the challenges in the bench to bedside translation.


Asunto(s)
Microbiota , Neoplasias , Humanos , Espectrometría Raman/métodos , Vibración
2.
Int J Mol Sci ; 23(15)2022 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-35897659

RESUMEN

Hepatocellular carcinoma (HCC) incidence, as well as related mortality, has been steadily increasing in the USA and across the globe, partly due to the lack of effective therapeutic options for advanced HCC. Though sorafenib is considered standard-of-care for advanced HCC, it only improves median survival by a few months when compared to placebo. Sorafenib is also associated with several unpleasant side effects that often lead to early abatement of therapy. Here, we investigate whether a combination regimen including low-dose sorafenib and a non-toxic dose of anti-diabetic drug metformin can achieve effective inhibition of HCC. Indeed, combining metformin with low-dose sorafenib inhibited growth, proliferation, migration, and invasion potential of HCC cells. We observed a 5.3- and 1.9-fold increase in sub-G1 population in the combination treatment compared to sorafenib alone. We found that the combination of metformin enhanced the efficacy of sorafenib and inhibited the MAPK/ERK/Stat3 axis. Our in vivo studies corroborated the in vitro findings, and mice harboring HepG2-derived tumors showed effective tumor reduction upon treatment with low-dose sorafenib and metformin combination. This work sheds light on a therapeutic strategy aiming to augment sorafenib efficacy or dose-de-escalation that may prove beneficial in circumventing sorafenib resistance as well as minimizing related side effects.


Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Metformina , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Metformina/farmacología , Metformina/uso terapéutico , Ratones , Niacinamida/farmacología , Niacinamida/uso terapéutico , Compuestos de Fenilurea/farmacología , Compuestos de Fenilurea/uso terapéutico , Sorafenib/farmacología , Sorafenib/uso terapéutico , Ensayos Antitumor por Modelo de Xenoinjerto
3.
Carcinogenesis ; 40(9): 1110-1120, 2019 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-30698683

RESUMEN

Withaferin A (WFA), a steroidal lactone, negatively regulates breast cancer growth however, its mechanisms of action remain largely elusive. We found that WFA blocks autophagy flux and lysosomal proteolytic activity in breast cancer cells. WFA increases accumulation of autophagosomes, LC3B-II conversion, expression of autophagy-related proteins and autophagosome/lysosome fusion. Autolysosomes display the characteristics of acidic compartments in WFA-treated cells; however, the protein degradation activity of lysosomes is inhibited. Blockade of autophagic flux reduces the recycling of cellular fuels leading to insufficient substrates for tricarboxylic acid (TCA) cycle and impaired oxidative phosphorylation. WFA decreases expression and phosphorylation of lactate dehydrogenase, the key enzyme that catalyzes pyruvate-to-lactate conversion, reduces adenosine triphosphate levels and increases AMP-activated protein kinase (AMPK) activation. AMPK inhibition abrogates while AMPK activation potentiates WFA's effect. WFA and 2-deoxy-d-glucose combination elicits synergistic inhibition of breast cancer cells. Genetic knockout of BECN1 and ATG7 fails to rescue cells from WFA treatment; in contrast, addition of methyl pyruvate to supplement TCA cycle protects WFA-treated cells. Together, these results implicate that WFA is a potent lysosomal inhibitor; energetic impairment is required for WFA-induced apoptosis and growth inhibition and combining WFA and 2-DG is a promising therapeutic strategy for breast cancer.

4.
Int J Mol Sci ; 20(10)2019 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-31121868

RESUMEN

Adiponectin is one of the most important adipocytokines secreted by adipocytes and is called a "guardian angel adipocytokine" owing to its unique biological functions. Adiponectin inversely correlates with body fat mass and visceral adiposity. Identified independently by four different research groups, adiponectin has multiple names; Acrp30, apM1, GBP28, and AdipoQ. Adiponectin mediates its biological functions via three known receptors, AdipoR1, AdipoR2, and T-cadherin, which are distributed throughout the body. Biological functions of adiponectin are multifold ranging from anti-diabetic, anti-atherogenic, anti-inflammatory to anti-cancer. Lower adiponectin levels have been associated with metabolic syndrome, type 2 diabetes, insulin resistance, cardiovascular diseases, and hypertension. A plethora of experimental evidence supports the role of obesity and increased adiposity in multiple cancers including breast, liver, pancreatic, prostrate, ovarian, and colorectal cancers. Obesity mediates its effect on cancer progression via dysregulation of adipocytokines including increased production of oncogenic adipokine leptin along with decreased production of adiponectin. Multiple studies have shown the protective role of adiponectin in obesity-associated diseases and cancer. Adiponectin modulates multiple signaling pathways to exert its physiological and protective functions. Many studies over the years have shown the beneficial effect of adiponectin in cancer regression and put forth various innovative ways to increase adiponectin levels.


Asunto(s)
Adiponectina/metabolismo , Neoplasias/metabolismo , Obesidad/metabolismo , Animales , Progresión de la Enfermedad , Humanos , Neoplasias/complicaciones , Neoplasias/patología , Obesidad/complicaciones , Obesidad/patología , Receptores de Adiponectina/metabolismo
5.
Oncology (Williston Park) ; 32(8): 410-7, 2018 08 15.
Artículo en Inglés | MEDLINE | ID: mdl-30153321

RESUMEN

Excess body weight is a significant risk factor for many cancers, especially breast cancer. Patients with breast cancer or those with a history of the disease who are overweight or obese have an increased risk of therapy-related morbidity, recurrence, and breast cancer-related mortality. Obesity may also affect quality-of-life factors for survivors, including sexual dysfunction, neuropathy, cardiotoxicity, chronic fatigue, and lymphedema. Most cancer guidelines recommend that breast cancer survivors who are overweight or obese lose weight and that those with a normal body mass index (BMI) maintain a stable body weight. The cornerstone of interventions to treat or prevent obesity is lifestyle modification with diet and exercise; however, integrating these things into clinical practice is challenging. This article will present feasible weight loss interventions, and will discuss practical implications of ongoing chemotherapy and endocrine therapy with regard to weight gain, and the impact of obesity on therapy-related conditions during breast cancer survivorship.


Asunto(s)
Neoplasias de la Mama/terapia , Supervivientes de Cáncer , Obesidad/complicaciones , Imagen Corporal , Neoplasias de la Mama/mortalidad , Fatiga/etiología , Femenino , Humanos , Obesidad/psicología , Calidad de Vida , Pérdida de Peso
6.
AAPS PharmSciTech ; 19(8): 3501-3511, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30259402

RESUMEN

Honokiol is a natural phenolic anti-cancer compound isolated from an extract of seed cones from Magnolia grandiflora. This study investigated the transdermal delivery of honokiol using various enhancement methods and to explore the potential of honokiol to treat breast cancer directly via delivery through mammary papilla. Poration of dermatomed human skin with microneedles significantly increased the delivery of honokiol by nearly 3-fold (97.81 ± 18.96 µg/cm2) compared with passive delivery (32.56 ± 5.67 µg/cm2). Oleic acid was found to be the best chemical penetration enhancer, increasing the delivery almost 27-fold (868.06 ± 100.91 µg/cm2). Addition of oleic acid also resulted in better retention of drug in the porcine mammary papilla (965.41 ± 80.26 µg/cm2) compared with breast skin (294.16 ± 8.49 µg/cm2). Anti-cancer effect of honokiol was demonstrated with the decrease in the release of cytokine IL-6 and further suppression of Ki-67 proliferative protein. In addition, the topical honokiol formulation investigated was found to be safe and non-irritant. In summary, both microneedles and chemical enhancers can improve the absorption of honokiol through skin. Directly applying honokiol on mammary papilla is a potential administration route which can increase localized delivery into breast tissue.


Asunto(s)
Compuestos de Bifenilo/administración & dosificación , Neoplasias de la Mama/tratamiento farmacológico , Lignanos/administración & dosificación , Absorción Cutánea , Administración Cutánea , Animales , Compuestos de Bifenilo/farmacocinética , Neoplasias de la Mama/metabolismo , Sistemas de Liberación de Medicamentos , Femenino , Humanos , Lignanos/farmacocinética , Piel/metabolismo , Porcinos
7.
Semin Cancer Biol ; 35 Suppl: S25-S54, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25892662

RESUMEN

Proliferation is an important part of cancer development and progression. This is manifest by altered expression and/or activity of cell cycle related proteins. Constitutive activation of many signal transduction pathways also stimulates cell growth. Early steps in tumor development are associated with a fibrogenic response and the development of a hypoxic environment which favors the survival and proliferation of cancer stem cells. Part of the survival strategy of cancer stem cells may manifested by alterations in cell metabolism. Once tumors appear, growth and metastasis may be supported by overproduction of appropriate hormones (in hormonally dependent cancers), by promoting angiogenesis, by undergoing epithelial to mesenchymal transition, by triggering autophagy, and by taking cues from surrounding stromal cells. A number of natural compounds (e.g., curcumin, resveratrol, indole-3-carbinol, brassinin, sulforaphane, epigallocatechin-3-gallate, genistein, ellagitannins, lycopene and quercetin) have been found to inhibit one or more pathways that contribute to proliferation (e.g., hypoxia inducible factor 1, nuclear factor kappa B, phosphoinositide 3 kinase/Akt, insulin-like growth factor receptor 1, Wnt, cell cycle associated proteins, as well as androgen and estrogen receptor signaling). These data, in combination with bioinformatics analyses, will be very important for identifying signaling pathways and molecular targets that may provide early diagnostic markers and/or critical targets for the development of new drugs or drug combinations that block tumor formation and progression.


Asunto(s)
Proteínas de Ciclo Celular/genética , Proliferación Celular/efectos de los fármacos , Neoplasias/patología , Neoplasias/terapia , Antineoplásicos/uso terapéutico , Proteínas de Ciclo Celular/biosíntesis , Transición Epitelial-Mesenquimal/efectos de los fármacos , Humanos , Terapia Molecular Dirigida , Neoplasias/genética , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Transducción de Señal/efectos de los fármacos
8.
Mol Cell ; 30(3): 336-47, 2008 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-18471979

RESUMEN

Estrogen receptor alpha (ER) is a ligand-dependent transcription factor. Upon binding estrogen, ER recruits coactivator complexes with histone acetyltransferase or methyltransferase activities to activate downstream target genes. In addition to histones, coactivators can modify ER itself and other proteins in the transactivation complex. Here, we show that ER is directly methylated at lysine 302 (K302) by the SET7 methyltransferase. SET7-mediated methylation stabilizes ER and is necessary for the efficient recruitment of ER to its target genes and for their transactivation. The SET7-ER complex structure reveals the molecular basis for ER peptide recognition and predicts that modifications or mutations of nearby residues would affect K302 methylation. Indeed, a breast cancer-associated mutation at K303 (K303R) alters methylation at K302 in vitro and in vivo. These findings raise the possibility that generation, recognition, and removal of modifications within the ER hinge region generate "ER modification cassettes" that yield distinct patterns for signaling downstream events.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , N-Metiltransferasa de Histona-Lisina/metabolismo , Lisina/metabolismo , Secuencia de Aminoácidos , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Línea Celular , Cristalografía por Rayos X , Receptor alfa de Estrógeno/química , Receptor alfa de Estrógeno/genética , Estrógenos/metabolismo , Femenino , Regulación de la Expresión Génica , Histona Metiltransferasas , N-Metiltransferasa de Histona-Lisina/química , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Metilación , Modelos Moleculares , Datos de Secuencia Molecular , Mutación , Péptidos/química , Péptidos/genética , Péptidos/metabolismo , Conformación Proteica , Proteína Metiltransferasas , Alineación de Secuencia
9.
J Mammary Gland Biol Neoplasia ; 18(3-4): 309-20, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24214584

RESUMEN

High plasma levels of leptin, a major adipocytokine produced by adipocytes, are correlated with increased fat mass in obese state. Leptin is emerging as a key candidate molecule linking obesity with breast cancer. Acting via endocrine, paracrine, and autocrine manner, leptin impacts various stages of breast tumorigenesis from initiation and primary tumor growth to metastatic progression. Leptin also modulates the tumor microenvironment mainly through supporting migration of endothelial cells, neo-angiogenesis and sustaining recruitment of macrophage and monocytes. Various studies have shown that hyperactive leptin-signaling network leads to concurrent activation of multiple oncogenic pathways resulting in enhanced proliferation, decreased apoptosis, acquisition of mesenchymal phenotype, potentiated migration and enhanced invasion potential of tumor cells. Furthermore, the capability of leptin to interact with other molecular effectors of obese state including, estrogen, IGF-1, insulin, VEGF and inflammatory cytokines further increases its impact on breast tumor progression in obese state. This article presents an overview of the studies investigating the involvement of leptin in breast cancer.


Asunto(s)
Neoplasias de la Mama/fisiopatología , Leptina/fisiología , Obesidad/fisiopatología , Animales , Neoplasias de la Mama/metabolismo , Femenino , Humanos , Obesidad/metabolismo , Receptores de Leptina/metabolismo , Factores de Riesgo , Transducción de Señal
10.
J Biol Chem ; 287(11): 8598-612, 2012 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-22270359

RESUMEN

Perturbations in the adipocytokine profile, especially higher levels of leptin, are a major cause of breast tumor progression and metastasis; the underlying mechanisms, however, are not well understood. In particular, it remains elusive whether leptin is involved in epithelial-mesenchymal transition (EMT). Here, we provide molecular evidence that leptin induces breast cancer cells to undergo a transition from epithelial to spindle-like mesenchymal morphology. Investigating the downstream mediator(s) that may direct leptin-induced EMT, we found functional interactions between leptin, metastasis-associated protein 1 (MTA1), and Wnt1 signaling components. Leptin increases accumulation and nuclear translocation of ß-catenin leading to increased promoter recruitment. Silencing of ß-catenin or treatment with the small molecule inhibitor, ICG-001, inhibits leptin-induced EMT, invasion, and tumorsphere formation. Mechanistically, leptin stimulates phosphorylation of glycogen synthase kinase 3ß (GSK3ß) via Akt activation resulting in a substantial decrease in the formation of the GSK3ß-LKB1-Axin complex that leads to increased accumulation of ß-catenin. Leptin treatment also increases Wnt1 expression that contributes to GSK3ß phosphorylation. Inhibition of Wnt1 abrogates leptin-stimulated GSK3ß phosphorylation. We also discovered that leptin increases the expression of an important modifier of Wnt1 signaling, MTA1, which is integral to leptin-mediated regulation of the Wnt/ß-catenin pathway as silencing of MTA1 inhibits leptin-induced Wnt1 expression, GSK3ß phosphorylation, and ß-catenin activation. Furthermore, analysis of leptin-treated breast tumors shows increased expression of Wnt1, pGSK3ß, and vimentin along with higher nuclear accumulation of ß-catenin and reduced E-cadherin expression providing in vivo evidence for a previously unrecognized cross-talk between leptin and MTA1/Wnt signaling in epithelial-mesenchymal transition of breast cancer cells.


Asunto(s)
Neoplasias de la Mama/metabolismo , Transición Epitelial-Mesenquimal , Glucógeno Sintasa Quinasa 3/metabolismo , Histona Desacetilasas/metabolismo , Leptina/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Represoras/metabolismo , Vía de Señalización Wnt , Proteína Wnt1/metabolismo , beta Catenina/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Compuestos Bicíclicos Heterocíclicos con Puentes/farmacología , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Núcleo Celular/genética , Núcleo Celular/metabolismo , Núcleo Celular/patología , Femenino , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/genética , Glucógeno Sintasa Quinasa 3/genética , Glucógeno Sintasa Quinasa 3 beta , Histona Desacetilasas/genética , Humanos , Leptina/genética , Leptina/farmacología , Fosforilación/efectos de los fármacos , Fosforilación/genética , Proteínas Proto-Oncogénicas c-akt/genética , Pirimidinonas/farmacología , Proteínas Represoras/genética , Transactivadores , Vimentina/genética , Vimentina/metabolismo , Proteína Wnt1/genética , beta Catenina/antagonistas & inhibidores , beta Catenina/genética
11.
Cells ; 12(8)2023 04 14.
Artículo en Inglés | MEDLINE | ID: mdl-37190065

RESUMEN

Despite an increase in the incidence of breast cancer worldwide, overall prognosis has been consistently improving owing to the development of multiple targeted therapies and novel combination regimens including endocrine therapies, aromatase inhibitors, Her2-targeted therapies, and cdk4/6 inhibitors. Immunotherapy is also being actively examined for some breast cancer subtypes. This overall positive outlook is marred by the development of resistance or reduced efficacy of the drug combinations, but the underlying mechanisms are somewhat unclear. It is interesting to note that cancer cells quickly adapt and evade most therapies by activating autophagy, a catabolic process designed to recycle damaged cellular components and provide energy. In this review, we discuss the role of autophagy and autophagy-associated proteins in breast cancer growth, drug sensitivity, tumor dormancy, stemness, and recurrence. We further explore how autophagy intersects and reduces the efficacy of endocrine therapies, targeted therapies, radiotherapy, chemotherapies as well as immunotherapy via modulating various intermediate proteins, miRs, and lncRNAs. Lastly, the potential application of autophagy inhibitors and bioactive molecules to improve the anticancer effects of drugs by circumventing the cytoprotective autophagy is discussed.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Resistencia a Antineoplásicos , Inmunoterapia , Autofagia
12.
Gut Microbes ; 15(1): 2221452, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37305949

RESUMEN

Regardless of the global progress in early diagnosis and novel therapeutic regimens, breast carcinoma poses a devastating threat, and the advances are somewhat marred by high mortality rates. Breast cancer risk prediction models based on the known risk factors are extremely useful, but a large number of breast cancers develop in women with no/low known risk. The gut microbiome exerts a profound impact on the host health and physiology and has emerged as a pivotal frontier in breast cancer pathogenesis. Progress in metagenomic analysis has enabled the identification of specific changes in the host microbial signature. In this review, we discuss the microbial and metabolomic changes associated with breast cancer initiation and metastatic progression. We summarize the bidirectional impact of various breast cancer-related therapies on gut microbiota and vice-versa. Finally, we discuss the strategies to modulate the gut microbiota toward a more favorable state that confers anticancer effects.


Asunto(s)
Neoplasias de la Mama , Microbioma Gastrointestinal , Microbiota , Femenino , Humanos , Neoplasias de la Mama/terapia , Metagenoma , Cognición
13.
NPJ Breast Cancer ; 9(1): 4, 2023 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-36702853

RESUMEN

Racial disparities are most accentuated among Black women as their lifetime risk of breast cancer incidence is lower than white and Asian women but their breast cancer related mortality is the highest among all races. Black women are more likely to develop triple-negative breast cancer at a younger age and harbor more aggressive tumors. In addition to tumor-centric alterations, tumor growth is also influenced by multiple other tumor microenvironment-related features, including resident immune cells and microbiota. Hence, in this study, we conduct concurrent genomic and metagenomic analyses, and uncover distinctive intratumoral microbial community compositions and tumor immune microenvironment-related traits in breast tumors from Asian, Black and white women. Interestingly, unique racially associated genomic nodes are found in the breast tumors from Asian, Black and white women. Examination of the cellular heterogeneity show differential enrichment of 11 out of 64 immune and stroma cell types in the breast tumors from different racial groups. In terms of microbial diversity, significant differences are revealed in alpha and beta-diversity measures. Intriguingly, potential race-specific microbial biomarkers of breast cancer are identified which significantly correlate with genes involved with tumor aggressiveness, angiogenesis, tumor cell migration and metastasis as well as oncogenic pathways-GLI and Notch. Investigating the metabolic features of intratumoral microbes, we find a significant differential enrichment of environmental information processing pathways, oncogenic pathways, and lipid metabolism pathways. Concomitantly investigating tumor-centric, tumor immune microenvironment-related and microbial alterations, our study provides a comprehensive understanding of racial disparities in breast cancer and warrants further exploration.

14.
Food Chem (Oxf) ; 6: 100167, 2023 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-36875800

RESUMEN

Jaboticaba peel (Myrciaria jaboticaba) is a source of bioactive compounds. We investigated the anticancer activity of ethyl acetate extract (JE1) and hydroethanolic extract (JE2) of Jaboticaba peel against breast cancer. Both JE1 and JE2 inhibited clonogenic potential of MDA-MB-231 cells while JE1 was particularly effective in MCF7 cells. Anchorage-independent growth and cell viability was also inhibited by JE1 and JE2. In addition to growth inhibition, JE1 and JE2 could also inhibit migration and invasion of cells. Interestingly, JE1 and JE2 show selective inhibition towards certain breast cancer cells and biological processes. Mechanistic evaluations showed that JE1 induced PARP cleavage, BAX and BIP indicating apoptotic induction. An elevation of phosphorylated ERK was observed in MCF7 cells in response to JE1 and JE2 along with increased IRE-α and CHOP expression indicating increased endoplasmic stress. Therefore, Jaboticaba peel extracts could be potentially considered for further development for breast cancer inhibition.

15.
Front Immunol ; 14: 1194931, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37503343

RESUMEN

Introduction: Obesity, an independent risk factor for breast cancer growth and metastatic progression, is also closely intertwined with gut dysbiosis; and both obese state and dysbiosis promote each other. Enteric abundance of Bacteroides fragilis is strongly linked with obesity, and we recently discovered the presence of B. fragilis in malignant breast cancer. Given that enterotoxigenic B. fragilis or ETBF, which secretes B. fragilis toxin (BFT), has been identified as a procarcinogenic microbe in breast cancer, it is necessary to examine its impact on distant metastasis and underlying systemic and localized alterations promoting metastatic progression of breast cancer. Methods: We used syngeneic mammary intraductal (MIND) model harboring gut colonization with ETBF to query distant metastasis of breast cancer cells. Alterations in the immune network and cytokines/chemokines in the tumor microenvironment and distant metastatic sites were examined using flow cytometry, immunohistochemistry, and multiplex arrays. Results: ETBF infection initiates a systemic inflammation aiding in the establishment of the premetastatic niche formation in vital organs via increased proinflammatory and protumorigenic cytokines like IL17A, IL17E, IL27p28, IL17A/F, IL6, and IL10 in addition to creating a prometastatic immunosuppressive environment in the liver and lungs rich in myeloid cells, macrophages, and T regulatory cells. It induces remodeling of the tumor microenvironment via immune cell and stroma infiltration, increased vasculogenesis, and an EMT-like response, thereby encouraging early metastatic dissemination ready to colonize the conducive environment in liver and lungs of the breast tumor-bearing mice. Discussion: In this study, we show that enteric ETBF infection concomitantly induces systemic inflammation, reshapes the tumor immune microenvironment, and creates conducive metastatic niches to potentiate early dissemination and seeding of metastases to liver and lung tissues in agreement with the "seed and soil hypothesis." Our results also support the ETBF-induced "parallel model" of metastasis that advocates for an early dissemination of tumor cells that form metastatic lesions independent of the primary tumor load.


Asunto(s)
Toxinas Bacterianas , Neoplasias Hepáticas , Neoplasias Pulmonares , Ratones , Animales , Disbiosis , Inflamación , Citocinas , Pulmón , Obesidad , Microambiente Tumoral
16.
Carcinogenesis ; 33(4): 918-30, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22345290

RESUMEN

Understanding the molecular pathways that contribute to the development of tamoxifen resistance is a critical research priority as acquired tamoxifen resistance is the principal cause of poor prognosis and death of patients with originally good prognosis hormone-responsive breast tumors. In this report, we provide evidence that Med1, an important subunit of mediator coactivator complex, is spontaneously upregulated during acquired tamoxifen-resistance development potentiating agonist activities of tamoxifen. Phosphorylated Med1 and estrogen receptor (ER) are abundant in tamoxifen-resistant breast cancer cells due to persistent activation of extracellular signal-regulated kinases. Mechanistically, phosphorylated Med1 exhibits nuclear accumulation, increased interaction with ER and higher tamoxifen-induced recruitment to ER-responsive promoters, which is abrogated by inhibition of Med1 phosphorylation. Stable knockdown of Med1 in tamoxifen-resistant cells not only reverses tamoxifen resistance in vitro but also in vivo. Finally, higher expression levels of Med1 in the tumor significantly correlated with tamoxifen resistance in ER-positive breast cancer patients on adjuvant tamoxifen monotherapy. In silico analysis of breast cancer, utilizing published profiling studies showed that Med1 is overexpressed in aggressive subsets. These findings provide what we believe is the first evidence for a critical role for Med1 in tamoxifen resistance and identify this coactivator protein as an essential effector of the tamoxifen-induced breast cancer growth.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Resistencia a Antineoplásicos/fisiología , Subunidad 1 del Complejo Mediador/fisiología , Tamoxifeno/farmacología , Western Blotting , Activación Enzimática , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Inmunoprecipitación , Subunidad 1 del Complejo Mediador/metabolismo , Microscopía Fluorescente , Fosforilación , Receptores de Estrógenos/fisiología
18.
Breast Cancer Res ; 14(1): R35, 2012 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-22353783

RESUMEN

INTRODUCTION: Honokiol, a small-molecule polyphenol isolated from magnolia species, is widely known for its therapeutic potential as an antiinflammatory, antithrombosis, and antioxidant agent, and more recently, for its protective function in the pathogenesis of carcinogenesis. In the present study, we sought to examine the effectiveness of honokiol in inhibiting migration and invasion of breast cancer cells and to elucidate the underlying molecular mechanisms. METHODS: Clonogenicity and three-dimensional colony-formation assays were used to examine breast cancer cell growth with honokiol treatment. The effect of honokiol on invasion and migration of breast cancer cells was evaluated by using Matrigel invasion, scratch-migration, spheroid-migration, and electric cell-substrate impedance sensing (ECIS)-based migration assays. Western blot and immunofluorescence analysis were used to examine activation of the liver kinase B1 (LKB1)-AMP-activated protein kinase (AMPK) axis. Isogenic LKB1-knockdown breast cancer cell line pairs were developed. Functional importance of AMPK activation and LKB1 overexpression in the biologic effects of honokiol was examined by using AMPK-null and AMPK-wild type (WT) immortalized mouse embryonic fibroblasts (MEFs) and isogenic LKB1-knockdown cell line pairs. Finally, mouse xenografts, immunohistochemical and Western blot analysis of tumors were used. RESULTS: Analysis of the underlying molecular mechanisms revealed that honokiol treatment increases AMP-activated protein kinase (AMPK) phosphorylation and activity, as evidenced by increased phosphorylation of the downstream target of AMPK, acetyl-coenzyme A carboxylase (ACC) and inhibition of phosphorylation of p70S6kinase (pS6K) and eukaryotic translation initiation factor 4E binding protein 1 (4EBP1). By using AMPK-null and AMPK-WT (MEFs), we found that AMPK is required for honokiol-mediated modulation of pACC-pS6K. Intriguingly, we discovered that honokiol treatment increased the expression and cytoplasmic translocation of tumor-suppressor LKB1 in breast cancer cells. LKB1 knockdown inhibited honokiol-mediated activation of AMPK and, more important, inhibition of migration and invasion of breast cancer cells. Furthermore, honokiol treatment resulted in inhibition of breast tumorigenesis in vivo. Analysis of tumors showed significant increases in the levels of cytoplasmic LKB1 and phospho-AMPK in honokiol-treated tumors. CONCLUSIONS: Taken together, these data provide the first in vitro and in vivo evidence of the integral role of the LKB1-AMPK axis in honokiol-mediated inhibition of the invasion and migration of breast cancer cells. In conclusion, honokiol treatment could potentially be a rational therapeutic strategy for breast carcinoma.


Asunto(s)
Proteínas Quinasas Activadas por AMP/metabolismo , Antineoplásicos/farmacología , Compuestos de Bifenilo/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Lignanos/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , Quinasas de la Proteína-Quinasa Activada por el AMP , Proteínas Quinasas Activadas por AMP/genética , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Antineoplásicos/uso terapéutico , Compuestos de Bifenilo/uso terapéutico , Neoplasias de la Mama/patología , Proteínas de Ciclo Celular , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Activación Enzimática/efectos de los fármacos , Femenino , Expresión Génica , Humanos , Lignanos/uso terapéutico , Ratones , Ratones Desnudos , Invasividad Neoplásica , Fosfoproteínas/metabolismo , Fosforilación , Procesamiento Proteico-Postraduccional/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Quinasas S6 Ribosómicas/metabolismo , Esferoides Celulares/efectos de los fármacos , Esferoides Celulares/fisiología , Serina-Treonina Quinasas TOR/metabolismo , Carga Tumoral/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto
19.
Artículo en Inglés | MEDLINE | ID: mdl-23320026

RESUMEN

The present study evaluates anti-hyperglycemic activity of fractionated Momordica charantia (bitter gourd) seed extracts. Fasting blood glucose levels were evaluated before and after administration of different fractions of the seed extract. Among the three fractions tested, fraction Mc-3 (15 mg/kg b.wt.) showed the maximum anti-hyperglycemic activity and reduced blood glucose levels in experimental diabetic rats significantly. The activities of the key regulatory enzymes of glucose metabolism (hexokinase, pyruvate kinase, lactate dehydrogenase, and glucose-6-phosphate dehydrogenase) were determined in Mc-3-treated diabetic animals. Once-daily administration of the fraction Mc-3 for prolonged period of 18 days to the experimental diabetic animals did not result in any nephrotoxicity or hepatotoxicity as evident from insignificant changes in biochemical parameters indicative of liver and kidney functions. Further fractionation of the fraction Mc-3 by size exclusion chromatography resulted in a fraction, designated Mc-3.2, possessing anti-hyperglycemic activity. The fraction Mc-3.2 showed the presence of a predominant protein band of ~11 kDa on SDS-PAGE. Loss in anti-hyperglycemic activity of the Mc-3.2 upon protease treatment indicates the proteinaceous nature of the anti-hyperglycemic principles. Overall, the results suggest that Momordica charantia seeds contain an effective anti-hyperglycemic protein(s) which may find application in treatment of diabetes without evident toxic effects.

20.
ACS Sens ; 7(5): 1495-1505, 2022 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-35583030

RESUMEN

Delineating the molecular and morphological changes that cancer cells undergo in response to extracellular stimuli is crucial for identifying factors that promote tumor progression. Label-free optical imaging offers a potentially promising route for retrieving such single-cell information by generating detailed visualization of the morphology and determining alterations in biomolecular composition. The potential of such nonperturbative morphomolecular microscopy for analyzing microbiota-cancer cell interactions has been surprisingly underappreciated, despite the growing evidence of the critical role of dysbiosis in malignant transformations. Here, using a model system of breast cancer cells, we show that label-free Raman microspectroscopy and quantitative phase microscopy can detect biomolecular and morphological changes in single cells exposed to Bacteroides fragilis toxin (BFT), a toxin secreted by enterotoxigenicB. fragilis. Remarkably, using machine learning to elucidate subtle, but consistent, cellular differences, we found that the morphomolecular differences between BFT-exposed and control breast cancer cells became more accentuated after in vivo passage, corroborating our findings that a short-term BFT exposure imparts a long-term effect on cancer cells and promotes a more invasive phenotype. Complementing more classical labeling techniques, our label-free platform offers a global detection approach with measurements representative of the overall cellular phenotype, paving the way for further investigations into the multifaceted interactions between the cancer cell and the microbiota.


Asunto(s)
Bacteroides fragilis , Neoplasias de la Mama , Bacteroides fragilis/genética , Recuento de Células , Femenino , Humanos , Microscopía , Vibración
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