RESUMEN

BACKGROUND/AIM: Kaempferol, a natural flavonoid, occurs abundantly in fruits and vegetables. It has various bioactivities, with antioxidant, anti-inflammatory, and other beneficial properties. The aim of this study was to investigate the in vitro effects of kaempferol on the proliferation, apoptosis, and autophagy of KB cells, a human cervical cancer cell line, and the corresponding action mechanisms. MATERIALS AND METHODS: The inhibitory efficacy of kaempferol on KB cervical cancer cells was investigated through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, migration assay, 4',6-diamidino-2-phenylindole staining, flow cytometry, acridine orange staining and western blotting. RESULTS: Kaempferol reduced KB cell viability and migration in a dose-dependent manner. Additionally, kaempferol-induced apoptosis was confirmed, and kaempferol treatment influenced levels of apoptotic proteins. Autophagy was detected upon visualization of characteristic autophagic vacuoles and acidic vesicular organelles, and verified using western blotting, which revealed elevated levels of autophagy-related proteins. Kaempferol-mediated apoptosis and autophagy were evidently attributable to reduced phosphorylation in the phosphoinositide 3-kinase (PI3K)/serine/threonine kinase 1 (AKT)/mammalian target of rapamycin (mTOR) pathway. This finding was validated using a pharmacological inhibition assay with the PI3K pathway inhibitor LY294002, which promoted KB cell apoptosis and autophagy. CONCLUSION: Our results suggest that kaempferol induces apoptosis and autophagy by inhibiting the PI3K/AKT/mTOR pathway in human cervical cancer cells, empirically showing the anticancer effects of kaempferol, and thereby presenting it as a potential anticancer therapeutic agent.

Asunto(s)

Apoptosis , Autofagia , Quempferoles , Fosfatidilinositol 3-Quinasas , Proteínas Proto-Oncogénicas c-akt , Transducción de Señal , Serina-Treonina Quinasas TOR , Neoplasias del Cuello Uterino , Humanos , Quempferoles/farmacología , Serina-Treonina Quinasas TOR/metabolismo , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Autofagia/efectos de los fármacos , Apoptosis/efectos de los fármacos , Transducción de Señal/efectos de los fármacos , Fosfatidilinositol 3-Quinasas/metabolismo , Femenino , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Movimiento Celular/efectos de los fármacos

RESUMEN

Gastric cancer is the fifth most common cancer globally and the third leading cause of cancer-related mortality. Existing treatment strategies for gastric cancer often present numerous side effects. Consequently, recent studies have shifted toward devising new treatments grounded in safer natural substances. α-Pinene, a natural terpene found in the essential oils of various plants, such as Lavender angustifolia and Satureja myrtifolia, displays antioxidant, antibiotic, and anticancer properties. Yet, its impact on gastric cancer remains unexplored. This research assessed the effects of α-pinene in vitro using a human gastric adenocarcinoma cell-line (AGS) human gastric cancer cells and in vivo via a xenograft mouse model. The survival rate of AGS cells treated with α-pinene was notably lower than that of the control group, as revealed by the 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide assay. This decline in cell viability was linked to apoptosis, as verified by 4',6-diamidino-2-phenylindole and annexin V/propidium iodide staining. The α-pinene-treated group exhibited elevated cleaved-poly (ADP-ribose) polymerase and B cell lymphoma 2 (Bcl-2)-associated X (Bax) levels and reduced Bcl-2 levels compared with the control levels. Moreover, α-pinene triggered the activation of extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38 within the mitogen-activated protein kinase (MAPK) pathway. In the xenograft mouse model, α-pinene induced apoptosis through the MAPK pathway, devoid of toxicity. These findings position α-pinene as a promising natural therapeutic for gastric cancer.

Asunto(s)

Monoterpenos Bicíclicos , Neoplasias Gástricas , Humanos , Animales , Ratones , Neoplasias Gástricas/tratamiento farmacológico , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Línea Celular Tumoral , Apoptosis , Quinasas MAP Reguladas por Señal Extracelular , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proliferación Celular

RESUMEN

Platycodin D (PD) is the main component of triterpene saponins found in Platycodi radix. In this study, we observed a decrease in cell viability, an increase in apoptotic bodies, and an increase in the rate of apoptosis. Also, we observed an increase in cleaved PARP and Bax, a decrease in Bcl-2, and p-ERK, and an increase in p-p38 and p-JNK. Furthermore, a change in cell viability and the expression of p-p38, Bax, and Bcl-2 using the p38 inhibitor revealed a decrease in p-p38 and Bax and an increase in Bcl-2 in the inhibitor treatment group. In addition, we observed an increase in vacuole formation through morphological changes and an increase in acidic vesicular organelles (AVOs). We also observed an increase in the expression of beclin 1, LC 3-I, and -II. There was no significant decrease in cell viability in the group treated with 3-MA, but a decrease in cell viability was noted in the group treated with HCQ. HCQ treatment resulted in an increase in Bax and a decrease in Bcl-2. These findings reveal that in HT-29 colon cancer cells, PD induces apoptosis through the MAPK pathway, thereby exerting anticancer effects. Moreover, autophagy caused by PD inhibits apoptosis by protecting the cells.

Asunto(s)

Neoplasias del Colon , Saponinas , Triterpenos , Humanos , Proteína X Asociada a bcl-2 , Saponinas/farmacología , Triterpenos/farmacología , Apoptosis , Autofagia , Neoplasias del Colon/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-bcl-2

RESUMEN

This study sought to determine the anticancer effect of kaempferol, a glycone-type flavonoid glycoside with various pharmacological benefits, on human oral cancer MC-3 cells. In vitro studies comprised a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, annexin V and propidium iodide staining, western blotting analysis, and acridine orange staining, while the in vivo studies entailed a xenograft model, hematoxylin and eosin staining, and TdT-mediated dUTP-biotin nick end labelling. In vitro, kaempferol reduced the rate of survival of MC-3 cells, mediated intrinsic apoptosis, increased the number of acidic vesicular organelles, and altered the expression of autophagy-related proteins. Further, treatment with the autophagy inhibitors revealed that the induced autophagy had a cytoprotective effect on apoptosis in kaempferol-treated MC-3 cells. Kaempferol also decreased the expression of phosphorylated extracellular signal-regulated kinase and increased that of phosphorylated c-Jun N-terminal kinase (p-JNK) and phosphorylated p38 kinase in MC-3 cells, suggesting the occurrence of mitogen-activated protein kinase-mediated apoptosis and JNK-mediated autophagy. In vivo, kaempferol reduced tumor growth inducing apoptosis and autophagy. These results showed that kaempferol has the potential use as an adjunctive agent in treating oral cancer.

RESUMEN

Piperlongumine (PL) is an amide alkaloid with diverse pharmacological effects against cancer, bronchitis and asthma; however, research on its efficacy against melanoma is lacking. The present study investigated the anticancer effects of PL on A375SM and A375P human melanoma cells. PL decreased the survival rate of A375SM and A375P cells, as shown by MTT assay, increase of apoptotic cells by DAPI staining. And PL induced apoptosis by decreasing the expression of the anti­apoptotic protein Bcl­2 and increasing that of the pro­apoptotic proteins cleaved­PARP and Bax. PL also induced apoptosis in A375SM and A375P cells via the MAPK pathway, increasing expression of the MAPK pathway proteins, phosphorylated­(p­ERK), p­JNK p­p38. These proteins were confirmed by western blot. In addition, A375SM and A375P cells treated with PL showed an increased number of acidic vesicular organelles by acridine orange staining. Also, autophagy induced by the expression of 1A/1B­light chain 3, Beclin 1and mTOR was investigated through western blot. When PL was applied following treatment with autophagy inhibitors 3­methyladenine and hydroxychloroquine, autophagy exhibited a cytoprotective effect against apoptosis in MTT assay. Pretreatment of A375P cells with the ERK inhibitor PD98059 and the JNK inhibitor SP600125 followed by treatment with PL confirmed that apoptosis and autophagy were mediated via the MAPK/ERK pathway by western blot. In summary, the present study provided empirical evidence supporting the anticancer effects of PL on human melanoma cells and indicated the potential of PL as a treatment for melanoma.

Asunto(s)

Apoptosis , Melanoma , Humanos , Línea Celular Tumoral , Melanoma/tratamiento farmacológico , Proteínas Reguladoras de la Apoptosis/metabolismo , Autofagia

RESUMEN

Currently, therapies for treating oral cancer have various side effects; therefore, research on treatment methods employing natural substances is being conducted. This study aimed to investigate piperine-induced apoptosis and autophagy in HSC-3 human oral cancer cells and their effects on tumor growth in vivo. A 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay demonstrated that piperine reduced the viability of HSC-3 cells and 4',6-diamidino-2-phenylindole staining, annexin-V/propidium iodide staining, and analysis of apoptosis-related protein expression confirmed that piperine induces apoptosis in HSC-3 cells. Additionally, piperine-induced autophagy was confirmed by the observation of increased acidic vesicular organelles and autophagy marker proteins, demonstrating that autophagy in HSC-3 cells induces apoptosis. Mechanistically, piperine induced apoptosis and autophagy by inhibiting the phosphatidylinositol-3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin pathway in HSC-3 cells. We also confirmed that piperine inhibits oral cancer tumor growth in vivo via antitumor effects related to apoptosis and PI3K signaling pathway inhibition. Therefore, we suggest that piperine can be considered a natural anticancer agent for human oral cancer.

RESUMEN

Oral cancer is a malignant tumor that primarily affects areas such as the lips, tongue, buccal mucosa, salivary gland, and gingiva and has a very high malignancy. Piperlongumine (PL), isolated from long pepper (Piper longum L.), is a natural alkaloid with pharmacological effects, such as anti-inflammatory and anti-atherosclerotic effects. The effect and mechanism of PL in oral cancer cell lines has not been explored. Therefore, this study aimed to investigate the mechanism of anticancer effects of PL in the human oral cancer cell lines MC-3 and HSC-4 in vitro. This study demonstrated that PL inhibits cell proliferation by inducing apoptosis and autophagy in human oral cancer cell lines, which was confirmed by the levels of apoptosis- and autophagy-related proteins through Western blotting. Moreover, the pharmacological blockade of autophagy activation by hydroxychloroquine (HCQ), an autophagy inhibitor, significantly improved PL-induced apoptosis in MC-3 cells, suggesting a cytoprotective effect. In addition, activation of the mitogen-activated protein kinase (MAPK) signaling pathway contributed to PL-induced apoptosis. Collectively, the study suggested that combining an autophagy inhibitor with PL treatment can exert effective anticancer properties in oral cancer cells by inducing apoptosis and cytoprotective autophagy via the JNK-mediated MAPK pathway.

RESUMEN

Natural products are continuously being researched to develop safe and effective treatment options for cervical cancer, the fourth most common cancer in women. Piperlongumine (PL), an amide alkaloid mainly present in long pepper, exhibits neuroprotective and anti-cancer properties. However, the specific effect of PL in cervical cancer and the relationship between the anti-cancer pathway and autophagy remain unclear. Therefore, we aimed to investigate PL-induced apoptosis in KB human cervical cancer cells and the relationship between apoptosis and autophagy therein. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and wound-healing assays showed that PL treatment suppressed KB cell viability and proliferation. Apoptosis was identified through 4',6-diamidino-2-phenylindole and annexin V-propidium iodide staining, increased cleaved-poly (ADP-ribose) polymerase and Bcl-2 associated X levels, and decreased B cell lymphoma 2 levels. Acridine orange staining and increased microtubule-associated protein 1A/1B-light chain 3-II and Beclin-1 levels confirmed autophagy. We determined that KB cell-related autophagy exerted cytoprotective effects using the autophagy inhibitors 3-methyladenine and hydroxychloroquine. PL treatment promoted apoptosis by inhibiting the phosphatidylinositol-3-kinase (PI3K)/protein kinase B/mammalian target of rapamycin pathway in KB cells; inhibiting the pathway using PI3K inhibitors increased autophagy. We suggest that PL is a potential natural anticancer agent for cervical cancer treatment.

RESUMEN

Chrysin is a flavonoid found abundantly in substances, such as honey and phytochemicals, and is known to exhibit anticancer effects against various cancer cells. Nevertheless, the anticancer effect of chrysin against oral cancer has not yet been verified. Furthermore, the mechanism underlying autophagy is yet to be clearly elucidated. Thus, this study investigated chrysin-mediated apoptosis and autophagy in human mucoepidermoid carcinoma (MC-3) cells. The change in MC-3 cell viability was examined using a 3-(4,5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide cell viability assay, as well as 40,6-diamidino-2-phenylindole, annexin V, and propidium iodide staining. Western blotting was used to analyze the proteins related to apoptosis and the mitogen-activated protein kinase (MAPK) pathway. In addition, the presence or absence of autophagy and changes in the expression of related proteins were investigated using acridine orange staining and Western blot. The results suggested that chrysin induced apoptosis and autophagy in MC-3 oral cancer cells via the MAPK/extracellular signal-regulated kinase pathway. Moreover, the induced autophagy exerted a cytoprotective effect against apoptosis. Thus, the further reduced cell viability due to autophagy as well as apoptosis induction highlight therapeutic potential of chrysin for oral cancer.

Asunto(s)

Apoptosis , Neoplasias de la Boca , Humanos , Serina-Treonina Quinasas TOR/metabolismo , Flavonoides/farmacología , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Autofagia , Línea Celular Tumoral , Neoplasias de la Boca/tratamiento farmacológico

RESUMEN

Chrysin is known to exert anti-inflammatory, antioxidant, and anticancer effects. The aim of this study was to investigate the anticancer effects of chrysin in the human melanoma cells A375SM and A375P. The results obtained demonstrated successful inhibition of the viability of these cells by inducing apoptosis and autophagy. This was confirmed by the level of apoptosis-related proteins: Bax and cleaved poly (ADP-ribose) polymerase both increased, and Bcl-2 decreased. Moreover, levels of LC3 and Beclin 1, both autophagy-related proteins, increased in chrysin-treated cells. Autophagic vacuoles and acidic vesicular organelles were observed in both cell lines treated with chrysin. Both cell lines showed different tendencies during chrysin-induced autophagy inhibition, indicating that autophagy has different effects depending on the cell type. In A375SM, the early autophagy inhibitor 3-methyladenine (3-MA) was unaffected; however, cell viability decreased when treated with the late autophagy inhibitor hydroxychloroquine (HCQ). In contrast, HCQ was unaffected in A375P; however, cell viability increased when treated with 3-MA. Chrysin also decreased the phosphorylation of mTOR/S6K pathway proteins, indicating that this pathway is involved in chrysin-induced apoptosis and autophagy for A375SM and A375P. However, studies to elucidate the mechanisms of autophagy and the action of chrysin in vivo are still needed.

RESUMEN

Tenebrio molitor larvae, as known as edible insects, has advantages of being rich in protein, and has been recognized as a suitable alternate protein source for broiler and pig feed. Moreover, given their ability to biodegrade polystyrene, a major pollutant, Tenebrio molitor larvae has been proposed as an innovative solution to environmental problems. In the present study, we investigated the toxicity of Tenebrio molitor larvae powder (TMlp) ingested with expanded-polystyrene (W/ eps) through in vitro and in vivo experiments. The objective of this study was to determine whether TMlp W/ eps can be applied as livestock alternative protein source. For in vitro experiments, cytotoxicity test was performed to investigate the effects of TMlp-extract on the viability of estrogen-dependent MCF-7 cells. The possibility of estrogen response was investigated in two groups: Expanded-polystyrene-fed (W/ eps) TMlp group and without expanded-polystyrene-fed (W/o eps) TMlp group. For in vivo experiments, The male Sprague-Dawley rats were divided based on the dosage of TMlp administered and oral administration was performed to every day for 5 weeks. A toxicological assessments were performed, which included clinical signs, food consumption, body and organ weights, hematology, serum chemistry, and hematoxylin and eosin staining of liver and kidney. There were no specific adverse effect of TMlp W/ eps-related findings under the experimental conditions of this study, but further studies on both sexes and animal species differences should be investigated. In conclusion, TMlp W/ eps was considered non-toxic and observed to be applicable as an alternative protein source for livestock feed.

RESUMEN

Myricetin, a natural flavonoid present in berries, nuts, and green tea, is well-known for its anticancer properties. Even though several previous studies have reported the anticancer effects induced by myricetin, these effects have not yet been confirmed in the adenocarcinoma gastric cell line (AGS). Moreover, the exact mechanisms of myricetin-induced apoptosis and autophagy have not been clearly identified either. Therefore, in this study, we aimed to examine the role of myricetin in inducing apoptosis and autophagy in AGS gastric cancer cells. First, the survival rate of AGS gastric cancer cells was assessed using the 3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide (MTT) cell viability assay. Thereafter, the rate of apoptosis was analyzed using4',6-diamidino-2-phenylindole (DAPI) staining as well as annexin V and propidium iodide (PI) staining, and the expression of the proteins associated with apoptosis, PI3K/Akt/mTOR pathway, and autophagy was examined by western blotting. We observed that myricetin reduced the survival rate of AGS gastric cancer cells by inhibiting the PI3K/Akt/mTOR pathway, thereby inducing apoptosis and autophagy. Similar results were also obtained in vivo, and tumor growth was inhibited. Therefore, in the AGS gastric cancer cells, myricetin seems to inhibit the PI3K/Akt/mTOR pathway, which in turn leads to apoptosis in vitroand in vivo, cell-protective autophagy, as well as inhibition of cancer cell proliferation. These results indicate the potential of myricetin as a natural anticancer agent.

RESUMEN

Myricetin, a flavonoid found in fruits and vegetables, is known to have antioxidant and anticancer effects. However, the anticancer effects of myricetin on SK­BR­3 human breast cancer cells have not been elucidated. In the present study, the anticancer effects of myricetin were confirmed in human breast cancer SK­BR­3 cells. As the concentration of myricetin increased, the cell viability decreased. DAPI (4',6­diamidino­2­phenylindole) and Annexin V/PI staining also revealed a significant increase in apoptotic bodies and apoptosis. Western blot analysis was performed to confirm the myricetin­induced expression of apoptosis­related proteins. The levels of cleaved PARP and Bax proteins were increased, and that of Bcl­2 was decreased. The levels of proteins in the mitogen­activated protein kinase (MAPK) pathway were examined to confirm the mechanism of myricetin­induced apoptosis, and it was found that the expression levels of phosphorylated c­Jun N­terminal kinase (p­JNK) and phosphorylated mitogen­activated protein kinases (p­p38) were increased, whereas that of phosphorylated extracellular­regulated kinase (p­ERK) was decreased. It was also demonstrated that myricetin induced autophagy by promoting autophagy­related proteins such as microtubule­associated protein 1A/1B­light chain 3 (LC 3) and beclin 1. In addition, 3­methyladenine (3­MA) was used to evaluate the association between cell viability and autophagy in cells treated with myricetin. The results showed that simultaneous treatment with 3­MA and myricetin promoted the apoptosis of breast cancer cells. Furthermore, treatment with a JNK inhibitor reduced cell viability, promoted Bax expression, and reduced the expression of p­JNK, Bcl­2, and LC 3­II/I. These results suggest that myricetin induces apoptosis via the MAPK pathway and regulates JNK­mediated autophagy in SK­BR­3 cells. In conclusion, myricetin shows potential as a natural anticancer agent in SK­BR­3 cells.

Asunto(s)

Apoptosis , Flavonoides , Sistema de Señalización de MAP Quinasas , Proteínas Quinasas Activadas por Mitógenos , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/enzimología , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Flavonoides/farmacología , Humanos

RESUMEN

PURPOSE: The purpose of this study was to present various clinical etiologies of hypermetabolic pelvic lesions on postoperative positron emission tomography/computed tomography (PET/CT) images for patients with rectal and sigmoid cancer. METHODS: Postoperative PET/CT images for patients with rectal and sigmoid cancer were retrospectively reviewed to identify hypermetabolic pelvic lesions. Positive findings were detected in 70 PET/CT images from 45 patients; 2 patients who were lost to follow-up were excluded. All PET findings were analyzed in comparison with contrast-enhanced CT. RESULTS: A total of 43 patients were classified into 2 groups: patients with a malignancy including local recurrence (n = 30) and patients with other benign lesions (n = 13). Malignant lesions such as a local recurrent tumor, peritoneal carcinomatosis, and incidental uterine malignancy, as well as various benign lesions such as an anastomotic sinus, fistula, abscess, reactive lymph node, and normal ovary, were observed. CONCLUSION: PET/CT performed during postoperative surveillance of rectal and sigmoid colon cancer showed increased fluorodeoxyglucose uptake not only in local recurrence, but also in benign pelvic etiologies. Therefore, physicians need to be cautious about the broad clinical spectrum of hypermetabolic pelvic lesions when interpreting images.

RESUMEN

Compared to normal cells, cancer cells have a higher level of reactive oxygen species (ROS) due to aberrant metabolism and disruption of redox homeostasis which drive their proliferation and promote progression and metastasis of cancers. The altered redox balance and biological difference between normal cells and cancer cells provide a basis for the development of anticancer agents which are able to generate pharmacological ROS insults to kill cancer cells preferentially. In this study, we report a new hybrid anticancer drug, termed OSamp, which undergoes esterase- and acid-catalyzed hydrolysis to deplete antioxidant glutathione (GSH) and generate ROS, simultaneously. OSamp significantly elevated oxidative stress in cancer cells, leading to enhanced apoptotic cancer cell death through mitochondrial membrane disruption, cytochrome c release, activation of pro-caspase 3, and deactivation of STAT3 (signal transducer and activator of transcription-3). OSamp, administered intravenously, significantly suppressed the tumor growth in a mouse model of tumor xenografts without notable side effects. Oxidative stress amplifying OSamp holds tremendous potential as a new anticancer therapeutic and provides a new therapeutic paradigm which can be extended to development of hybrid anticancer drugs.

Asunto(s)

Antineoplásicos/uso terapéutico , Neoplasias del Colon/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Profármacos/uso terapéutico , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Colon/efectos de los fármacos , Colon/metabolismo , Colon/patología , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Diseño de Fármacos , Humanos , Ratones , Profármacos/química , Profármacos/farmacología , Especies Reactivas de Oxígeno/metabolismo

RESUMEN

We report the simple and effective method for enhancing the photocatalytic properties of Degussa P25 TiO2 by low frequency ultrasonication. The improvement in the crystallinity of ultrasonicated TiO2 was confirmed by the X-ray diffraction and Raman spectroscopy studies. Further, the X-ray photoelectron spectroscopy was utilized to study the changes in chemical nature and band edge due to the effect of ultrasonication and H2O2 solvent. The transmission electron microscope (TEM) was used to analysis the surface distortion. The Moire fringes in TEM were examined to understand the partial transformation of amorphous to crystalline anatase structure and overlapping of rutile over anatase crystal. The photocatalytic results indicated improvement in the degradation of methylene blue dye. The degradation efficiency was estimated to be 86% for ultrasonicated TiO2, which is higher as compared to 40% of P25. The rate constant values revealed four times superior degradation property of ultrasonicated TiO2. The improvement in the photocatalytic efficiency was correlated to the formation of rutile/anatase TiO2 aggregation and its consequences on electron-hole recombination.

Asunto(s)

Nanopartículas del Metal/química , Nanopartículas del Metal/efectos de la radiación , Azul de Metileno/química , Sonicación/métodos , Titanio/química , Titanio/efectos de la radiación , Catálisis/efectos de la radiación , Ondas de Choque de Alta Energía , Luz , Ensayo de Materiales , Nanopartículas del Metal/ultraestructura , Azul de Metileno/efectos de la radiación , Tamaño de la Partícula

RESUMEN

We report an economical and eco-friendly way to remove the heavy metal pollutant using modified clay. The modification of clay was done by calcining the natural clay from Kyushu region in Japan. Further, the removal efficiency for various pH and contact time was evaluated. The morphology of the clays was studied using the scanning electron microscopy (SEM). The structural and chemical analyses of modified clay were done by using X-ray diffraction (XRD), Raman spectroscopy, and Energy dispersion analysis (EDAX) to understand the properties related to the removal of heavy metal pollutant. Further, we studied the absorption efficiency of clay for various pH and contacting time using Ni polluted water. The modified clays show better removal efficiency for all pH with different saturation time. The adsorption follows pseudo-second order kinetics and the adsorption capacity of modified clay is 1.5 times larger than that of natural clay. The increase in the adsorption efficiency of modified clay was correlated to the increase in hematite phase along with increase in surface area due to surface morphological changes.

RESUMEN

Cancer cells, compared to normal cells, are under oxidative stress associated with an elevated level of reactive oxygen species (ROS) and are more vulnerable to oxidative stress induced by ROS generating agents. Thus, manipulation of the ROS level provides a logical approach to kill cancer cells preferentially, without significant toxicity to normal cells, and great efforts have been dedicated to the development of strategies to induce cytotoxic oxidative stress for cancer treatment. Fenton reaction is an important biological reaction in which irons convert hydrogen peroxide (H2O2) to highly toxic hydroxyl radicals that escalate ROS stress. Here, we report Fenton reaction-performing polymer (PolyCAFe) micelles as a new class of ROS-manipulating anticancer therapeutic agents. Amphiphilic PolyCAFe incorporates H2O2-generating benzoyloxycinnamaldehyde and iron-containing compounds in its backbone and self-assembles to form micelles that serve as Nano-Fenton reactors to generate cytotoxic hydroxyl radicals, killing cancer cells preferentially. When intravenously injected, PolyCAFe micelles could accumulate in tumors preferentially to remarkably suppress tumor growth, without toxicity to normal tissues. This study demonstrates the tremendous translatable potential of Nano-Fenton reactors as a new class of anticancer drugs.

Asunto(s)

Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/farmacología , Hierro/química , Hierro/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Fragmentación del ADN/efectos de los fármacos , Compuestos Ferrosos/química , Células HEK293 , Humanos , Peróxido de Hidrógeno/metabolismo , Peróxido de Hidrógeno/uso terapéutico , Concentración de Iones de Hidrógeno , Radical Hidroxilo/química , Radical Hidroxilo/farmacología , Hierro/uso terapéutico , Metalocenos , Ratones , Ratones Desnudos , Micelas , Células 3T3 NIH , Neoplasias/tratamiento farmacológico , Neoplasias/patología , Polímeros/síntesis química , Polímeros/química , Especies Reactivas de Oxígeno/metabolismo , Trasplante Heterólogo

RESUMEN

Cancer cells, compared with normal cells, are under oxidative stress associated with the increased generation of reactive oxygen species (ROS) including H2O2 and are also susceptible to further ROS insults. Cancer cells adapt to oxidative stress by upregulating antioxidant systems such as glutathione to counteract the damaging effects of ROS. Therefore, the elevation of oxidative stress preferentially in cancer cells by depleting glutathione or generating ROS is a logical therapeutic strategy for the development of anticancer drugs. Here we report a dual stimuli-responsive hybrid anticancer drug QCA, which can be activated by H2O2 and acidic pH to release glutathione-scavenging quinone methide and ROS-generating cinnamaldehyde, respectively, in cancer cells. Quinone methide and cinnamaldehyde act in a synergistic manner to amplify oxidative stress, leading to preferential killing of cancer cells in vitro and in vivo. We therefore anticipate that QCA has promising potential as an anticancer therapeutic agent.

Asunto(s)

Antineoplásicos/farmacología , Compuestos de Boro/farmacología , Ésteres/farmacología , Estrés Oxidativo/efectos de los fármacos , Animales , Antineoplásicos/síntesis química , Antineoplásicos/química , Compuestos de Boro/síntesis química , Compuestos de Boro/química , Línea Celular , Cromatografía Liquida/métodos , Fragmentación del ADN , Ésteres/síntesis química , Ésteres/química , Peróxido de Hidrógeno , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Neoplasias Experimentales/tratamiento farmacológico , Distribución Aleatoria , Especies Reactivas de Oxígeno , Espectrometría de Masas en Tándem

RESUMEN

Cancer cells are under oxidative stress due to a large production of reactive oxygen species (ROS), which involve in cell proliferation and cancer promotion and progression. On the other hand, ROS promotes cell death, depending on the rate of ROS production and the activity of antioxidant systems. Recently, "oxidation therapy" has arisen as a promising anticancer strategy, which can be achieved by inducing the generation of cytotoxic level of ROS or inhibiting the antioxidant systems in tumor cells. Here, we report oxidative stress amplifying nanoplatforms as novel anticancer therapeutics, which are able not only to suppress antioxidant but also to generate ROS simultaneously in acidic tumor microenvironments. The oxidative stress amplifying nanoplatforms are composed of dual pH-sensitive PBCAE copolymer, polymeric prodrug of BCA (benzoyloxycinnamaldehyde) and heme oxygenase-1 (HO-1) inhibiting zinc protoporphyrin (ZnPP). PBCAE was designed to incorporate ROS-generating BCA in its backbone via acid-cleavable acetal linkages and self-assemble to form micelles that encapsulate ZnPP. In vitro proof-of-concept studies revealed that ZnPP encapsulated in PBCAE micelles suppressed HO-1 to make cancer cells more vulnerable to BCA-induced ROS, leading to enhanced apoptotic cell death. In addition, ZnPP-loaded PBCAE micelles significantly suppressed the tumor growth in human cancer xenograft mouse models. We believe that oxidative stress amplifying micellar nanoparticles have a great potential as novel redox anticancer therapeutics.

Asunto(s)

Antineoplásicos/farmacología , Micelas , Nanopartículas , Estrés Oxidativo/efectos de los fármacos , Acroleína/análogos & derivados , Acroleína/farmacología , Animales , Apoptosis/efectos de los fármacos , Benzoatos/farmacología , Supervivencia Celular/efectos de los fármacos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacología , Hemo-Oxigenasa 1/antagonistas & inhibidores , Humanos , Concentración de Iones de Hidrógeno , Ratones , Ratones Desnudos , Polímeros , Protoporfirinas/farmacología , Especies Reactivas de Oxígeno/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto