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1.
Ann N Y Acad Sci ; 1529(1): 14-20, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37676814

RESUMEN

Thalassemia management has undergone significant development with the advancement in iron chelation therapy, which has led to a prolonged life expectancy. This has been accompanied by the emergence of several new morbidities and chronic diseases, including cancer. Over the years, multiple cases of solid and hematologic malignancies in thalassemia patients have been reported in the literature, with no clear mechanism for the development of cancer in these patients despite a number of potential mechanisms. However, the results of many studies have been contradictory regarding the risk of development of malignancies in thalassemia. The present review aims to discuss the available data on cancer and thalassemia in the literature, with the latest updates regarding possible malignancy development mechanisms, risks, and the most commonly reported types.


Asunto(s)
Neoplasias Hematológicas , Sobrecarga de Hierro , Neoplasias , Talasemia , Humanos , Transfusión Sanguínea/métodos , Talasemia/complicaciones , Talasemia/epidemiología , Talasemia/terapia , Neoplasias/epidemiología , Neoplasias Hematológicas/epidemiología , Quelantes del Hierro/uso terapéutico , Sobrecarga de Hierro/complicaciones
3.
Front Immunol ; 14: 1191912, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37359547

RESUMEN

The outcome of B-cell acute lymphoblastic leukemia (B-ALL) has improved over time with the incorporation of multi-agent chemotherapy in the treatment landscape as well as the recent approval of immunotherapeutic agents allowing a larger proportion of patients to undergo allogeneic hematopoietic cell transplantation (allo-HCT) which is still considered a potential curative approach. However, relapse post-transplant is still occurring and constitutes a common cause of treatment failure in B-ALL. The present review aims to discuss the novel strategies and therapies used to prevent and overcome relapse post allo-HCT in patients with ALL, focusing on the role of tyrosine kinase inhibitors in Philadelphia chromosome positive B-ALL, the role of innovative agents such as blinatumomab and inotuzumab ozogamicin, and finally the role of cellular therapy.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Leucemia-Linfoma Linfoblástico de Células Precursoras B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Leucemia-Linfoma Linfoblástico de Células Precursoras/etiología , Inotuzumab Ozogamicina/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Recurrencia
4.
Surg Neurol Int ; 13: 496, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36447889

RESUMEN

Background: Granular cell tumors (GCTs) are uncommon peripheral nerve sheath tumors of Schwann cell origin that may occur throughout the body. However, they rarely occur in the spinal canal. Case Description: A 49-year-old male presented with burning sensation in the left knee. The MRI of the lumbar spine showed an L3-L4 intradural extramedullary tumor. Complete surgical resection was successfully performed and the L3 root burning improved. Histopathologically, the lesion proved to be a benign GCT. Conclusion: Spinal GCTs are rare benign tumors that may be found in an intradural extramedullary location in the spine. The preferred treatment is complete surgical resection as subtotal/partial resection may result in recurrence warranting radiation therapy.

5.
SAGE Open Med ; 10: 20503121221132352, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36277445

RESUMEN

Comprehensive genomic profiling is a next-generation sequencing approach used to detect several known and emerging genomic alterations. Many genomic variants detected by comprehensive genomic profiling have become recognized as significant cancer biomarkers, leading to the development of major clinical trials. Lung adenocarcinoma has become one of the most targeted cancers for genomic profiling with a series of actionable mutations such as EGFR, KRAS, HER2, BRAF, FGFR, MET, ALK, and many others. The importance of these mutations lies in establishing targeted therapies that significantly change the outcome in lung adenocarcinoma besides the prognostic value of some mutations. This review sheds light on the development of the comprehensive genomic profiling field, mainly lung adenocarcinoma, and discusses the role of a group of mutations in this disease.

6.
Curr Mol Pharmacol ; 15(7): 980-986, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35100963

RESUMEN

BACKGROUND: Breast Cancer is one of the most commonly diagnosed cancers worldwide and a major cause of death among women. Although chemotherapeutic agents remain the keystones in cancer therapy, significant side effects have failed to provide a safe and tolerable treatment for cancer patients. Dietary antioxidant vitamins were extensively investigated over the past years and their relevance in cancer chemotherapy remains to be elucidated. OBJECTIVE: In the current study, we aimed to investigate the anti-proliferative and apoptotic effects of combining γ-tocotrienol, a member of the vitamin E family, with the chemotherapeutic drug etoposide in MCF-7 and MDA-MB-231 breast cancer cell lines. METHODS: The antiproliferative effect of etoposide combined with γ-tocotrienol was measured using MTS viability reagent. The pro-apoptotic effect was elucidated through Cell Death ELISA and dual Annexin V/PI staining followed by flow cytometric analysis. RESULTS: Our results showed that etoposide significantly decreased the cell growth of both cell lines, with MDA-MB-231 cells being more sensitive to etoposide treatment than MCF-7. Moreover, simultaneous treatment of both breast cancer cell lines with low doses of γ-tocotrienol and etoposide induced a synergistic antiproliferative effect (CI<1). Furthermore, the combination therapy significantly increased the percentage of total apoptotic cells in the MDA-MB-231 cell line and the degree of DNA fragmentation as compared to treatment with either compound alone. CONCLUSION: In conclusion, our results provide evidence for the profound anti-tumorigenic effect of combined etoposide and γ-tocotrienol in the breast cancer cell lines.


Asunto(s)
Neoplasias de la Mama , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular , Cromanos , Etopósido/farmacología , Etopósido/uso terapéutico , Femenino , Humanos , Células MCF-7 , Vitamina E/análogos & derivados , Vitamina E/farmacología , Vitamina E/uso terapéutico
7.
Blood Rev ; 53: 100912, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34887154

RESUMEN

The prospect of hemophilia patients has dramatically improved in the last few decades with the introduction of various interventions that can effectively treat or prevent their bleeding risk. The life expectancy of patients can now reach that of the healthy population, but this has paved the way for several previously unrecognized morbidities to manifest in older adults with hemophilia. Such clinical complications are attributed to suboptimal management or poor access to effective therapy during childhood as well as chronicity and prolonged exposure to the underlying pathophysiology of the disease and its treatment. Complications common in the aging population are also becoming increasingly relevant in this vulnerable patient subgroup. In this review, we highlight peculiarities of such morbidities including chronic viral infections and liver disease, debilitating joint impairment and bone disease, cardiovascular and chronic kidney disease, and cancers. We also reflect on topics of special interest in adulthood such as sexuality.


Asunto(s)
Hemofilia A , Neoplasias , Adulto , Anciano , Envejecimiento , Hemofilia A/complicaciones , Hemofilia A/epidemiología , Hemofilia A/terapia , Humanos , Neoplasias/complicaciones
8.
Ann Hematol ; 100(5): 1115-1122, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33527161

RESUMEN

COVID-19 pandemic has imposed worldwide challenge and has significantly affected transfusion medicine. Shortage in blood products along with concerns regarding the safety of blood products have emerged. Measures to overcome these challenges have been implemented in order to decrease the demand on blood products and to encourage blood donations while taking full precautions to minimize risk of COVID-19 transmission mainly at blood banks and medical centers. Several countries have been successful in facing these new challenges. In addition, the role of plasma therapy in the treatment of COVID-19 patients, especially in severe cases, has been proposed and current studies are being conducted to determine its efficacy. Other therapeutic options are currently being explored. So far, the use of convalescent plasma is considered a promising rescue treatment to be looked at.


Asunto(s)
Seguridad de la Sangre , COVID-19/terapia , Medicina Transfusional , Donantes de Sangre/provisión & distribución , Seguridad de la Sangre/efectos adversos , Seguridad de la Sangre/métodos , COVID-19/epidemiología , COVID-19/transmisión , Humanos , Inmunización Pasiva/métodos , Medicina Transfusional/métodos , Resultado del Tratamiento , Sueroterapia para COVID-19
9.
Biomed Pharmacother ; 132: 110884, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33080470

RESUMEN

Flaxseeds have been known for their anti-cancerous effects due to the high abundance of lignans released upon ingestion. The most abundant lignan, secoisolariciresinol diglucoside (SDG), is ingested during the dietary intake of flax, and is then metabolized in the gut into two mammalian lignan derivatives, Enterodiol (END) and Enterolactone (ENL). These lignans were previously reported to possess anti-tumor effects against breast, colon, and lung cancer. This study aims to investigate the potential anti-cancerous effect of the flaxseed lignans SDG, END and ENL on acute myeloid leukemia cells (AML) in vitro and to decipher the underlying molecular mechanism. AML cell lines, (KG-1 and Monomac-1) and a normal lymphoblastic cell line were cultured and treated with the purified lignans. ENL was found to be the most promising lignan, as it exhibits a significant selective dose- and time-dependent cytotoxic effect in both AML cell lines, contrary to normal cells. The cytotoxic effects observed were attributed to apoptosis induction, as revealed by an increase in Annexin V staining of AML cells with increasing ENL concentrations. The increase in the percentage of cells in the pre-G phase, in addition to cell death ELISA analysis, validated cellular and DNA fragmentation respectively. Analysis of protein expression using western blots confirmed the activation of the intrinsic apoptotic pathway upon ENL treatment. This was also accompanied by an increase in ROS production intracellularly. In conclusion, this study demonstrates that ENL has promising anti-cancer effects in AML cell lines in vitro, by promoting DNA fragmentation and the intrinsic apoptotic pathway, highlighting the protective health benefits of flax seeds in leukemia.


Asunto(s)
4-Butirolactona/análogos & derivados , Antineoplásicos Fitogénicos/farmacología , Lino , Leucemia Mieloide Aguda/tratamiento farmacológico , Lignanos/farmacología , Extractos Vegetales/farmacología , Semillas , 4-Butirolactona/aislamiento & purificación , 4-Butirolactona/farmacología , Antineoplásicos Fitogénicos/aislamiento & purificación , Apoptosis/efectos de los fármacos , Butileno Glicoles/aislamiento & purificación , Butileno Glicoles/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Niño , Femenino , Lino/química , Glucósidos/aislamiento & purificación , Glucósidos/farmacología , Humanos , Leucemia Mieloide Aguda/patología , Lignanos/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Especies Reactivas de Oxígeno/metabolismo , Semillas/química
10.
Expert Rev Hematol ; 13(10): 1081-1092, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32931348

RESUMEN

INTRODUCTION: Many patients with inherited or acquired benign hematological disorders are at increased risk of developing severe complications from COVID-19. These patients, therefore, require specific advice regarding isolation and changes to their usual treatment schedules. Their disease can also be associated with significant burden, and they necessitate life-long and regular access to therapy, and regular follow-up consultations and hospital visits. The current COVID-19 pandemic is therefore presenting many challenges for these patients, their families, and health-care professionals. AREAS COVERED: This review provides an overview of the reported COVID-19 cases in the literature in patients with certain benign hematological disorders including thalassemia, sickle cell disease, hemophilia, immune thrombocytopenia, venous thromboembolism, and aplastic anemia. The review also outlines some recommendations on how to manage these patients if they are infected with SARS-CoV-2. To review the literature on benign hematological disorders and COVID-19, a bibliographic search was performed using PubMed for articles published between January 2020 and June 2020. EXPERT OPINION: International efforts must be made to continue reporting and better understanding the effects of SARS-CoV-2 infection in these patients and accordingly develop a set of recommendations to optimize the treatment of future infected patients.


Asunto(s)
Infecciones por Coronavirus/complicaciones , Enfermedades Hematológicas/complicaciones , Neumonía Viral/complicaciones , Betacoronavirus/aislamiento & purificación , COVID-19 , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/terapia , Manejo de la Enfermedad , Personal de Salud , Enfermedades Hematológicas/terapia , Humanos , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/terapia , SARS-CoV-2
11.
Nutrients ; 12(9)2020 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-32872275

RESUMEN

Urtica dioica (UD), commonly known as "stinging nettle", is a herbaceous flowering plant that is a widely used agent in traditional medicine worldwide. Several formulations of UD leaf extract have been reported to exhibit anti-inflammatory and antioxidant properties, with anticancer potential. The current study investigated the possible anticancer properties of nettle tea, prepared from Urtica dioica leaves, on acute myeloid leukemia (AML) cell lines, and deciphered the underlying molecular mechanisms. Treatment of AML cell lines (U-937 and KG-1) with UD aqueous leaf extract resulted in a dose- and time-dependent inhibition of proliferation, an increase in apoptotic hallmarks such as phosphatidylserine flipping to the outer membrane leaflet, and DNA fragmentation as revealed by cell-death ELISA and cell-cycle analysis assays. Apoptosis induction in U937 cells involves alterations in the expression of Bax and Bcl-2 upon exposure to nettle tea. Furthermore, the chemical composition of UD aqueous extract indicated the presence of multiple chemical agents, such as flavonoids and phenolics, mainly patuletin, m/p-hydroxybenzoic acid, and caffeic acid, among others, to which the pro-apoptotic and anti-tumor effects may be attributed.


Asunto(s)
Apoptosis/efectos de los fármacos , Leucemia Mieloide Aguda/tratamiento farmacológico , Extractos Vegetales/farmacología , Urtica dioica , Proliferación Celular/efectos de los fármacos , Humanos , Técnicas In Vitro
12.
Biomolecules ; 10(4)2020 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-32283796

RESUMEN

Studies on tocotrienols have progressively revealed the benefits of these vitamin E isoforms on human health. Beta-tocotrienol (beta-T3) is known to be less available in nature compared to other vitamin E members, which may explain the restricted number of studies on beta-T3. In the present study, we aim to investigate the anti-proliferative effects and the pro-apoptotic mechanisms of beta-T3 on two human breast adenocarcinoma cell lines MDA-MB-231 and MCF7. To assess cell viability, both cell lines were incubated for 24 and 48 h, with different concentrations of beta-T3 and gamma-T3, the latter being a widely studied vitamin E isoform with potent anti-cancerous properties. Cell cycle progression and apoptosis induction upon treatment with various concentrations of the beta-T3 isoform were assessed. The effect of beta-T3 on the expression level of several apoptosis-related proteins p53, cytochrome C, cleaved-PARP-1, Bax, Bcl-2, and caspase-3, in addition to key cell survival proteins p-PI3K and p-GSK-3 α/ß was determined using western blot analysis. Beta-tocotrienol exhibited a significantly more potent anti-proliferative effect than gamma-tocotrienol on both cell lines regardless of their hormonal receptor status. Beta-T3 induced a mild G1 arrest on both cell lines, and triggered a mitochondrial stress-mediated apoptotic response in MDA-MB-231 cells. Mechanistically, beta-T3's anti-neoplastic activity involved the downregulation of phosphorylated PI3K and GSK-3 cell survival proteins. These findings suggest that vitamin E beta-T3 should be considered as a promising anti-cancer agent, more effective than gamma-T3 for treating human breast cancer and deserves to be further studied to investigate its effects in vitro and on other cancer types.


Asunto(s)
Apoptosis/efectos de los fármacos , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Cromanos/farmacología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Vitamina E/análogos & derivados , Ciclo Celular/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Femenino , Humanos , Concentración 50 Inhibidora , Regulación hacia Arriba/efectos de los fármacos , Vitamina E/farmacología
13.
Cells ; 8(12)2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31766421

RESUMEN

Atypical epigenetic processes including histone acetylation and DNA methylation have been identified as a fundamental theme in hematologic malignancies. Such mechanisms modify gene expression and prompt, in part at least, the initiation and progression of several malignancies including acute myeloid leukemia. In the current study we determined the effects of treating KG-1 and U937 acute myeloid leukemia (AML) cells, in vitro, with the HDAC inhibitor, suberoylanilide hydroxamic acid (SAHA), or with a DNMT inhibitor, decitabine (DAC), or their combination, on cell proliferation, cell cycle progression, apoptosis, and expression of apoptosis-related proteins. Each of SAHA and DAC attenuated cell proliferation and induced cell cycle arrest and apoptotic cell death of KG-1 and U937 cell lines. Besides, their sequential combination improved the obtained anti-neoplastic effect: significant augmentation of growth inhibition and apoptosis induction as compared to cells treated with either drug alone. This effect was featured by the upregulated expression of Bax, cytochrome c1, p21, and cleaved caspases 8, 9, and 3, signifying the activation of both the intrinsic and extrinsic pathways of apoptosis. The sequential combination of SAHA and DAC causes a profound antitumorigenic effect in AML cell lines by inducing the expression of tumor suppressor genes.


Asunto(s)
Decitabina/farmacología , Leucemia Mieloide Aguda/terapia , Vorinostat/farmacología , Adyuvantes Farmacéuticos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Puntos de Control del Ciclo Celular/efectos de los fármacos , División Celular/efectos de los fármacos , Línea Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Epigénesis Genética/genética , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Leucemia Mieloide Aguda/genética , Células U937
14.
Blood Rev ; 37: 100585, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31253373

RESUMEN

The thalassemias constitute a variable group of anemias that result from autosomal recessive inherited defects in the production of hemoglobin. The life expectancy of thalassemia patients has been extended over the last decades as a result of key milestones being achieved in optimizing management with transfusion and iron chelation therapy. Such advances have prolonged the survival of thalassemia patients and improved their overall quality of life. However, this increase in life expectancy has led to the manifestation of several morbidities, including multiple types of solid and hematologic malignancies. In this review we report the different types of solid and hematological malignancies that can develop in thalassemia patients, in addition to the possible predisposing factors and mechanisms behind their development.


Asunto(s)
Neoplasias/etiología , Talasemia/complicaciones , Humanos
15.
Curr Mol Pharmacol ; 12(4): 281-300, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30868973

RESUMEN

BACKGROUND: Colorectal Cancer (CRC) is a common cause of oncological deaths worldwide. Alterations of the epigenetic landscape constitute a well-documented hallmark of CRC phenotype. The accumulation of aberrant DNA methylation and histone acetylation plays a major role in altering gene activity and driving tumor onset, progression and metastasis. OBJECTIVE: In this study, we evaluated the effect of Suberoylanilide Hydroxamic Acid (SAHA), a panhistone deacetylase inhibitor, and Decitabine (DAC), a DNA methyltransferase inhibitor, either alone or in combination, on Caco-2 human colon cancer cell line in vitro. RESULTS: Our results showed that SAHA and DAC, separately, significantly decreased cell proliferation, induced apoptosis and cell cycle arrest of Caco-2 cell line. On the other hand, the sequential treatment of Caco-2 cells, first with DAC and then with SAHA, induced a synergistic anti-tumor effect with a significant enhancement of growth inhibition and apoptosis induction in Caco-2 cell line as compared to cells treated with either drug alone. Furthermore, the combination therapy upregulates protein expression levels of pro-apoptotic proteins Bax, p53 and cytochrome c, downregulates the expression of antiapoptotic Bcl-2 protein and increases the cleavage of procaspases 8 and 9; this suggests that the combination activates apoptosis via both the intrinsic and extrinsic pathways. Mechanistically, we demonstrated that the synergistic anti-neoplastic activity of combined SAHA and DAC involves an effect on PI3K/AKT and Wnt/ß-catenin signaling. CONCLUSION: In conclusion, our results provide evidence for the profound anti-tumorigenic effect of sequentially combined SAHA and DAC in the CRC cell line and offer new insights into the corresponding underlined molecular mechanism.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias del Colon/tratamiento farmacológico , Decitabina/farmacología , Inhibidores Enzimáticos/farmacología , Vorinostat/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Apoptosis/efectos de los fármacos , Células CACO-2 , Neoplasias del Colon/genética , Neoplasias del Colon/patología , Metilasas de Modificación del ADN/antagonistas & inhibidores , Sinergismo Farmacológico , Epigénesis Genética/efectos de los fármacos , Inhibidores de Histona Desacetilasas/farmacología , Humanos
16.
Cancer Manag Res ; 10: 1079-1088, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29785137

RESUMEN

BACKGROUND: Topotecan (TP) is an anticancer drug acting as topoisomerase I inhibitor that is used in the treatment of many types of cancers including leukemia, but it has significant side effects. Andrographolide, a compound extracted from Andrographis paniculata, was recently proven to inhibit the growth of cancer cells and can induce apoptosis. The aim of this study is to investigate the possible synergism between TP and andrographolide in acute myeloid cells in vitro. MATERIALS AND METHODS: U937 acute myeloid leukemic cells were cultured using Roswell Park Memorial Institute (RPMI) medium and then treated for 24 h with TP and andrographolide prepared through the dilution of dimethyl sulfoxide (DMSO) stocks with RPMI on the day of treatment. Cell proliferation was assessed using cell proliferation assay upon treatment with both compounds separately and in combination. Cell-cycle study and apoptosis detection were performed by staining the cells with propidium iodide (PI) stain and Annexin V/PI stain, respectively, followed by flow cytometry analysis. Western blotting was used to assess the expression of various proteins involved in apoptotic pathways. RESULTS: Both TP and andrographolide showed an antiproliferative effect in a dose-dependent manner when applied on U937 cells separately; however, pretreating the cells with andrographolide before applying TP exhibited a synergistic effect with lower inhibitory concentrations (half-maximal inhibitory concentration). Treating the cells with TP alone led to specific cell-cycle arrest at S phase that was more prominent upon pretreatment combination with andrographolide. Using Annexin V/PI staining to assess the proapoptotic effect following the pretreatment combination showed an increase in the number of apoptotic cells, which was supported by the Western blot results that manifested an upregulation of several proapoptotic proteins expression. CONCLUSION: The pretreatment of U937 with andrographolide followed by low doses of TP showed an enhancement in inducing apoptosis when compared to the application of each compound separately.

17.
Planta Med ; 82(4): 312-21, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26848703

RESUMEN

Topotecan, a topoisomerase I inhibitor, is an anticancer drug widely used in the therapy of lung, ovarian, colorectal, and breast adenocarcinoma. Due to the primary dose-limiting toxicity of topotecan, which is myelosuppressive, it is necessary to identify other chemotherapeutic agents that can work synergistically with topotecan to increase its efficacy and limit its toxicity. Many studies have shown synergism upon the combination of topotecan with other chemotherapeutic agents such as gemcitabine. Other studies have demonstrated that pre-exposing cells to naturally occurring compounds such as thymoquinone, followed by gemcitabine or oxaliplatin, resulted in higher growth inhibition compared to treatment with gemcitabine or oxaliplatin alone. Our aim was to elucidate the underlying mechanism of action of topotecan in the survival and apoptotic pathways in human colon cancer cell lines in comparison to thymoquinone, to study the proapoptotic and antiproliferative effects of thymoquinone on the effectiveness of the chemotherapeutic agent topotecan, and to investigate the potential synergistic effect of thymoquinone with topotecan. Cells were incubated with different topotecan and thymoquinone concentrations for 24 and 48 hours in order to determine the IC50 for each drug. Combined therapy was then tested with ± 2 values for the IC50 of each drug. The reduction in proliferation was significantly dose- and time-dependent. After determining the best combination (40 µM thymoquinone and 0.6 µM topotecan), cell proteins were extracted after treatment, and the expression levels of B-cell lymphoma 2 and of its associated X protein, proteins p53 and p21, and caspase-9, caspase-3, and caspase-8 were studied by Western blot. In addition, cell cycle analysis and annexin/propidium iodide staining were performed. Both drugs induced apoptosis through a p53-independent mechanism, whereas the expression of p21 was only seen in thymoquinone treatment. Cell cycle arrest in the S phase was detected with each compound separately, while combined treatment only increased the production of fragmented DNA. Both compounds induced apoptosis through the extrinsic pathway after 24 hours; however, after 48 hours, the intrinsic pathway was activated by topotecan treatment only. In conclusion, thymoquinone increased the effectiveness of the chemotherapeutic reagent topotecan by inhibiting proliferation and lowering toxicity through p53- and Bax/Bcl2-independent mechanisms.


Asunto(s)
Antineoplásicos/uso terapéutico , Benzoquinonas/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Nigella sativa/química , Inhibidores de Topoisomerasa I/uso terapéutico , Topotecan/uso terapéutico , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Sinergismo Farmacológico , Células HT29 , Humanos , Semillas
18.
Clin Lymphoma Myeloma Leuk ; 14 Suppl: S46-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25486955

RESUMEN

BACKGROUND: Topotecan has shown promising antineoplastic activity in solid tumors and acute leukemia. Because of the primary dose-limiting toxicity of topotecan, it is necessary to identify other agents that can work synergistically with topotecan, potentially increasing its efficacy while limiting its toxicity. Many studies showed synergism in combination of topotecan with gemcitabine and bortezomib. Other studies report the increase in growth inhibition of gemcitabine or oxaliplatin when cells were preexposed to naturally occurring drugs such as thymoquinone. The aim of this project was to study the mode of action of topotecan along with thymoquinone, on survival and apoptosis pathways in acute myelogenous leukemia (AML) cell lines, and to investigate the potential synergistic effect of thymoquinone on topotecan. MATERIALS AND METHODS: U937 cells were incubated with different topotecan and thymoquinone concentrations for 24 and 48 hours, separately and in combination. Cell proliferation was determined using WST-1 (Roche) reagent. The effect of the compounds on protein expression of Bax, Bcl2, p53, caspase-9, -8, and -3 was determined using Western blot analysis. Cell cycle analysis was performed in addition to annexin/propidium iodide staining. RESULTS: Thymoquinone and topotecan exhibited antiproliferative effects on U937 cells when applied separately. In combination, the reduction in proliferation was extremely significant with a major increase in the expression levels of Bax/Bcl2, p53, and caspase-3 and -9. Preexposure with thymoquinone resulted in an increase in cell growth inhibition compared with topotecan treatment. CONCLUSION: Thymoquinone, when combined with topotecan in noncytotoxic doses, produced synergistic antiproliferative and proapoptotic effects in AML cells. Preexposure to thymoquinone seems to be more effective than simultaneous application with topotecan.


Asunto(s)
Benzoquinonas/farmacología , Leucemia Mieloide Aguda/metabolismo , Topotecan/farmacología , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Humanos , Leucemia Mieloide Aguda/tratamiento farmacológico , Transducción de Señal/efectos de los fármacos , Inhibidores de Topoisomerasa I/farmacología
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