curcumin and Carcinoma--Renal-Cell

To explore the effect of curcumin on the proliferation of renal cell carcinoma and analyze its regulation mechanism.. In RCC cell lines of A498 and 786-O, the effects of curcumin (2.5, 5, 10 µ mo/L) on the proliferation were analyzed by Annexin V+PI staining. Besides, A498 was inoculated into nude mice to establish tumorigenic models, and the model mice were treated with different concentrations of curcumin (100, 200, and 400 mg/kg), once daily for 30 days. Then the tumor diameter was measured, the tumor cells were observed by hematoxylin-eosin staining, and the protein expressions of miR-148 and ADAMTS18 were detected by immunohistochemistry. In vitro, after transfection of miR-148 mimics, miR-148 inhibitor or si-ADAMTS18 in cell lines, the expression of ADAMTS18 was examined by Western blotting and the cell survival rate was analyzed using MTT. Subsequently, Western blot analysis was again used to examine the autophagy phenomenon by measuring the relative expression level of LC3-II/LC3-I; autophagy-associated genes, including those of Beclin-1 and ATG5, were also examined when miR-148 was silenced in both cell lines with curcumin treatment.. Curcumin could inhibit the proliferation of RCC in cell lines and nude mice. The expression of miR-148 and ADAMTS18 was upregulated after curcumin treatment both in vitro and in vivo (P<0.05). The cell survival rate was dramatically declined upon miR-148 or ADAMTS18 upregulated. However, si-ADAMTS18 treatment or miR-148 inhibitor reversed these results, that is, both of them promoted the cell survival rate.. Curcumin can inhibit the proliferation of renal cell carcinoma by regulating the miR-148/ ADAMTS18 axis through the suppression of autophagy in vitro and in vivo. There may exist a positive feedback loop between miR-148 and ADAMTS18 gene in RCC.

Topics: ADAMTS Proteins; Animals; Autophagy; Carcinoma, Renal Cell; Cell Line, Tumor; Cell Proliferation; Curcumin; Gene Expression Regulation, Neoplastic; Kidney Neoplasms; Mice; Mice, Nude; MicroRNAs

To investigate the effect of curcumin on viability of clear cell renal cell carcinoma (ccRCC) and analyze its possible mechanism.. In cell lines of A498 and 786-O, the effects of curcumin (1.25, 2.5, 5 and 10 μ mol/L) on the viability of ccRCC were analyzed at 24, 48 and 72 h by MTT assay. The protein expression levels of ADAMTS18 gene, p65, phosphorylation p65 (pp65), AKT, phosphorylation AKT (pAKT) and matrix metallopeptidase 2 (MMP-2) before and after curcumin (10 μ mol/L) treatment were examined by Western blotting. Real-time PCR and methylation specific PCR (MSP) were applied to analyze the expression and methylation level of ADAMTS18 gene before and after curcumin treatment (10 μ mol/L).. Curcumin significantly inhibited the viability of A498 and 786-O cell lines in a dose- and time-dependent manner (P<0.01). Up-regulation of ADAMTS18 gene expression with down-regulation of ADAMTS18 gene methylation was reflected after curcumin treatment, accompanied by down-regulation of nuclear factor κ B (NF-κ kB) related protein (p65 and pp65), AKT related protein (AKT and pAKT), and NF-κ B/AKT common related protein MMP-2. With ADAMTS18 gene overexpressed, the expression levels of p65, AKT and MMP2 were downregulated, of which were conversely up-regulated in silenced ADAMTS18 (sh-ADAMTS18). The expression of pp65, pAKT and MMP2 in sh-ADAMTS18 was down-regulated after being treated with PDTC (NF-κ B inhibitor) and LY294002 (AKT inhibitor).. Curcumin could inhibit the viability of ccRCC by down-regulating ADAMTS18 gene methylation though NF-κ B and AKT signaling pathway.

Topics: ADAMTS Proteins; Carcinoma, Renal Cell; Cell Line, Tumor; Curcumin; DNA Methylation; Female; Humans; Kidney Neoplasms; Male; Matrix Metalloproteinase 2; NF-kappa B; Proto-Oncogene Proteins c-akt; Signal Transduction

This study was designed to reveal the protective effects of dietary supplementation of curcumin against renal cell tumours and oxidative stress induced by renal carcinogen iron nitrilotriacetate (Fe-NTA) in ddY male mice. The results showed that mice treated with a renal carcinogen, Fe-NTA, a 35% renal cell tumour incidence was noticed, whereas renal cell tumour occurrence was elevated to 80% in Fe-NTA promoted and N-diethylnitrosamine (DEN)-initiated mice as compared with saline- treated mice. No incidence of tumours has been observed in DEN-initiated non-promoted mice. Diet complemented with 0.5% and 1.0% curcumin fed prior to, during and after treatment with Fe-NTA in DEN-initiated animals, tumour incidence was reduced dose-dependently to about 45% and 30% respectively. Immunohistochemical studies also revealed the increased formation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts and 8-hydroxy-2'-deoxyguanosine (8-OHdG) in kidney tissue of mice treated with an intraperitoneal injection of Fe-NTA (6.0 mg Fe/kg body weight.). Furthermore, Fe-NTA treatment of mice also resulted in significant elevation of malondialdehyde (MDA), serum urea, and creatinine and decreases renal glutathione. However, the changes in most of these parameters were attenuated dose-dependently by prophylactic treatment of animals with 0.5% and 1% curcumin diet, this may be due to its antioxidative impact of curcumin. These results suggest that intake of curcumin is beneficial for the prevention of renal cell tumours and oxidative stress damage mediated by renal carcinogen, Fe-NTA.

Topics: 8-Hydroxy-2'-Deoxyguanosine; Aldehydes; Animals; Anticarcinogenic Agents; Antineoplastic Agents, Phytogenic; Antioxidants; Blood Urea Nitrogen; Carcinogens; Carcinoma, Renal Cell; Creatinine; Curcumin; Diet; Diethylnitrosamine; Dose-Response Relationship, Drug; Ferric Compounds; Kidney Neoplasms; Male; Mice; Nitrilotriacetic Acid; Oxidative Stress

Curcumin has a vital role in the development of renal carcinoma. Nevertheless, the mechanism of curcumin in renal carcinoma tumorigenesis remains largely unknown. Thirty renal carcinoma patients were recruited. Renal carcinoma cell lines CAKI-1 and ACHN were exposed to curcumin. The levels of circular RNA fibronectin type III domain-containing protein 3B (circ-FNDC3B), microRNA (miR)-138-5p and insulin-like growth factor 2 (IGF2) were detected via quantitative reverse transcription PCR or western blot. Cell proliferation and apoptosis were investigated via 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide, colony formation analysis, flow cytometry and western blot. Target association between miR-138-5p and circ-FNDC3B or IGF2 was analyzed via dual-luciferase reporter analysis. The function of curcumin in vivo was assessed via a xenograft model. circ-FNDC3B level was enhanced and miR-138-5p abundance was declined in renal carcinoma tissues and cells. Curcumin restrained renal carcinoma cell proliferation and promoted apoptosis. circ-FNDC3B overexpression or miR-138-5p knockdown weakened the influence of curcumin. circ-FNDC3B knockdown hindered cell proliferation and promoted apoptosis by increasing miR-138-5p. IGF2 was targeted via miR-138-5p and positively regulated via circ-FNDC3B. Curcumin decreased xenograft tumor growth via reducing circ-FNDC3B in vivo. Curcumin suppressed renal carcinoma tumorigenesis in vitro and in vivo via regulating circ-FNDC3B/miR-138-5p/IGF2 axis, proposing new insight into renal carcinoma tumorigenesis.

Topics: Animals; Apoptosis; Carcinoma, Renal Cell; Cell Line, Tumor; Cell Movement; Cell Proliferation; Curcumin; Fibronectins; Gene Expression Regulation, Neoplastic; Humans; Insulin-Like Growth Factor II; Kidney Neoplasms; Mice; Mice, Inbred BALB C; MicroRNAs; Signal Transduction; Xenograft Model Antitumor Assays

Long non-coding RNAs (lncRNAs) have been demonstrated to exert important roles in cancer development and progression. The biological function of lncRNA X-inactive specific transcript (XIST) in the development of renal cell carcinoma (RCC) and the underlying mechanisms are still largely unknown. In this study, we found that XIST was down-regulated in RCC tissues and cells. Overexpression of XIST significantly suppressed cell proliferation and induced cell G0/G1 arrest in vitro and inhibited tumor growth in vivo. We further found that XIST could directly interact with miR-106b-5p and increase the expression of P21. Thus, XIST positively regulated the expression of P21 through sponging miR-106b-5p, and played a tumor suppressor role in RCC. Moreover, we found that curcumin could regulate XIST/miR-106b-5p/P21 axis in RCC cells. Our study exhibits the role of XIST as a miRNA sponge in RCC and supports the potential application of XIST in RCC therapy.

Topics: Animals; Carcinoma, Renal Cell; Cell Line, Tumor; Cell Survival; Curcumin; Cyclin-Dependent Kinase Inhibitor p21; Disease Progression; G1 Phase Cell Cycle Checkpoints; Gene Expression Regulation, Neoplastic; Humans; Kidney Neoplasms; Mice, Inbred BALB C; MicroRNAs; Resting Phase, Cell Cycle; RNA, Long Noncoding

The anti-cancer properties of curcumin in vitro have been documented. However, its clinical use is limited due to rapid metabolization. Since irradiation of curcumin has been found to increase its anti-cancer effect on several tumor types, this investigation was designed to determine whether irradiation with visible light may enhance the anti-tumor effects of low-dosed curcumin on renal cell carcinoma (RCC) cell growth and proliferation. A498, Caki1, and KTCTL-26 cells were incubated with curcumin (0.1⁻0.4 µg/mL) and irradiated with 1.65 J/cm² visible light for 5 min. Controls were exposed to curcumin or light alone or remained untreated. Curcumin plus light, but not curcumin or light exposure alone altered growth, proliferation, and apoptosis of all three RCC tumor cell lines. Cells were arrested in the G0/G1 phase of the cell cycle. Phosphorylated (p) CDK1 and pCDK2, along with their counter-receptors Cyclin B and A decreased, whereas p27 increased. Akt-mTOR-signaling was suppressed, the pro-apoptotic protein Bcl-2 became elevated, and the anti-apoptotic protein Bax diminished. H3 acetylation was elevated when cells were treated with curcumin plus light, pointing to an epigenetic mechanism. The present findings substantiate the potential of combining low curcumin concentrations and light as a new therapeutic concept to increase the efficacy of curcumin in RCC.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Renal Cell; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Curcumin; Gene Knockdown Techniques; Humans; Light

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Renal Cell; Cell Line, Tumor; Cell Nucleus; Curcuma; Gene Expression Regulation, Neoplastic; Gold; Humans; Kidney Neoplasms; Metal Nanoparticles; Mitochondria; Plant Extracts; Reactive Oxygen Species; Spectroscopy, Fourier Transform Infrared

The aim of this study was to explore the effects of curcumin on renal cell carcinoma（RCC） through regulating autophagy. Cell viabilities were determined by MTT assay in RCC cells after treatment with curcumin at different concentrations for various durations. ATG7 silencing RCC cells were established to test the role of autophagy. The levels of key proteins on autophagy pathway were analyzed by Western blot. We found out that following 24 h curcumin treatment, the viability of RCC cells had an increase at 5 μM and no significant change at 20 μM but a decrease at 80 μM. These effects were affected by the inhibition of autophagy. When pre-incubated with inhibitors of the AMPK and ER stress pathways, the LC3II levels of RCC cells at 5 μM and 20 μM of curcumin were significantly decreased; however, when treated with the inhibitor of the oxidative stress pathway, the LC3II levels of RCC cells at 80 μM were significantly decreased. In conclusion, the present study indicated Curcumin protected cells from death at low concentration but promotes cell death at high concentration. Autophagy played a dual role in curcumin's effects on RCC. The AMPK and ER stress pathways might be involved at low concentrations of curcumin to protect cells, while the oxidative stress pathway might take part in toxicity at high curcumin concentration.

Topics: Acetylcysteine; AMP-Activated Protein Kinases; Antineoplastic Agents; Autophagy; Carcinoma, Renal Cell; Cell Line, Tumor; Cell Survival; Curcumin; Endoplasmic Reticulum Stress; Humans; Kidney Neoplasms; Oxidative Stress; Phenylbutyrates; Pyrazoles; Pyrimidines; Signal Transduction

The radiation resistance of renal cell carcinoma (RCC) remains the primary obstacle to improve patient survival. This study aimed to investigate the effects of curcumin on the radiosensitivity of RCC cells. Human RCC cell (ACHN) was exposed to irradiation (IR) and/or curcumin treatment. Cell viability, DNA repair, cell cycle, and apoptosis, were evaluated by MTT, immunofluoresence staining and flow cytometry. Moreover, ACHN cells were xenografted into nude mice and subjected to IR and/or curcumin treatment. The expression of NF-κB signaling related proteins in ACHN cells and xenografts was detected by western blot analysis. The results showed that curcumin significantly increased radiosensitivity of ACHN cells by inhibiting the cell proliferation and DNA damage repair, causing cell cycle arrest at G2/M phase, inducing apoptosis in vitro, and suppressing the growth of xenografts in vivo. In addition, curcumin enhanced radiosensitivity was through markedly inhibiting IR-induced NF-κB signaling by modulating the related protein expressions including NF-κBP65, I-κB, VEGF, COX2, and Bcl-2 in ACHN cells, which was further strengthened by NF-κB inhibitor PDTC treatment. Thus, curcumin may confer radiosensitivity on RCC via inhibition of NF-κB activation and its downstream regulars, suggesting the potential application of curcumin as an adjuvant in radiotherapy of RCC.

Topics: Animals; Apoptosis; Carcinoma, Renal Cell; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Proliferation; Curcumin; Cyclooxygenase 2; Female; G2 Phase Cell Cycle Checkpoints; Humans; I-kappa B Proteins; Mice; Mice, Inbred BALB C; Mice, Nude; NF-kappa B; Proto-Oncogene Proteins c-bcl-2; Radiation Tolerance; Signal Transduction; Vascular Endothelial Growth Factor A

Curcumin possesses anti-cancer effects. In the current study, we tested the effect of curcumin on cell proliferation, viability, apoptosis, cell cycle phases, and activation of the PI3K/Akt pathway in the renal cell carcinoma (RCC) cell line RCC-949. We observed that cell proliferation and viability were markedly inhibited by curcumin, while cell apoptosis was promoted. The latter effect was associated with increased expression of Bcl-2 and diminished expression of Bax (both: mRNA and protein). The cells treated with curcumin increasingly went into cell cycle arrest, which was likely mediated by diminished expression of cyclin B1, as seen in curcumin-treated cells. In addition, curcumin decreased activation of the PI3K/AKT signaling pathway. In conclusion, our results demonstrate that curcumin exerts anti-cancer effects by negative modulation of the PI3K/AKT signaling pathway and may represent a promising new drug to treat RCC.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Carcinoma, Renal Cell; Cell Cycle Checkpoints; Cell Line, Tumor; Cell Survival; Curcumin; Humans; Kidney Neoplasms; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Signal Transduction

The PI3K/Akt and mTOR signaling pathways are important for cell survival and growth, and they are highly activated in cancer cells compared with normal cells. Therefore, these signaling pathways are targets for inducing cancer cell death. The dual PI3K/Akt and mTOR inhibitor NVP-BEZ235 completely inhibited both signaling pathways. However, NVP-BEZ235 had no effect on cell death in human renal carcinoma Caki cells. We tested whether combined treatment with natural compounds and NVP-BEZ235 could induce cell death. Among several chemopreventive agents, curcumin, a natural biologically active compound that is extracted from the rhizomes of Curcuma species, markedly induced apoptosis in NVP-BEZ235-treated cells. Co-treatment with curcumin and NVP-BEZ235 led to the down-regulation of Mcl-1 protein expression but not mRNA expression. Ectopic expression of Mcl-1 completely inhibited curcumin plus NVP-NEZ235-induced apoptosis. Furthermore, the down-regulation of Bcl-2 was involved in curcumin plus NVP-BEZ235-induced apoptosis. Curcumin or NVP-BEZ235 alone did not change Bcl-2 mRNA or protein expression, but co-treatment reduced Bcl-2 mRNA and protein expression. Combined treatment with NVP-BEZ235 and curcumin reduced Bcl-2 expression in wild-type p53 HCT116 human colon carcinoma cells but not p53-null HCT116 cells. Moreover, Bcl-2 expression was completely reversed by treatment with pifithrin-α, a p53-specific inhibitor. Ectopic expression of Bcl-2 also inhibited apoptosis in NVP-BE235 plus curcumin-treated cells. In contrast, NVP-BEZ235 combined with curcumin did not have a synergistic effect on normal human skin fibroblasts and normal human mesangial cells. Taken together, combined treatment with NVP-BEZ235 and curcumin induces apoptosis through p53-dependent Bcl-2 mRNA down-regulation at the transcriptional level and Mcl-1 protein down-regulation at the post-transcriptional level.

Topics: Apoptosis; Blotting, Western; Carcinoma, Renal Cell; Cell Line, Tumor; Cell Proliferation; Cell Survival; Curcumin; DNA Fragmentation; Flow Cytometry; Humans; Imidazoles; Phosphoinositide-3 Kinase Inhibitors; Proto-Oncogene Proteins c-akt; Quinolines; Reverse Transcriptase Polymerase Chain Reaction; RNA, Small Interfering; Signal Transduction; TOR Serine-Threonine Kinases

Males have a higher incidence of renal cell carcinoma (RCC) than females, but the reason for this gender difference is unknown. Addressing this question, we report the discovery of an androgen receptor (AR)-induced HIF2α/VEGF signal that drives RCC progression. AR attenuation or augmentation in RCC cells altered their proliferation, migration, and invasion in multiple models in vitro and in vivo. Mechanistic investigations revealed that AR targeting inhibited RCC cell migration and invasion by modulating HIF2α/VEGF signals at the level of mRNA and protein expression. Interrupting HIF2α/VEGF signals with inhibitors of either HIF2α or VEGF was sufficient to suppress RCC progression. Similarly, the specific AR degradation enhancer ASC-J9 was sufficient to suppress AR-induced HIF2α/VEGF signaling and RCC progression in multiple models in vitro and in vivo. Taken together, our results revealed a novel role for AR in RCC initiation and progression with implications for novel therapeutic strategies.

Topics: Animals; Carcinoma, Renal Cell; Cell Growth Processes; Cell Line, Tumor; Cell Movement; Curcumin; Disease Progression; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Kidney Neoplasms; Male; Mice; Mice, Nude; Signal Transduction; Vascular Endothelial Growth Factor A; Xenograft Model Antitumor Assays

This study investigated the influence of curcumin on HOX transcript antisense RNA (HOTAIR)- mediated migration of cultured renal cell carcinoma (RCC) cells.. Five RCC cell lines (769-P, 769-P-vector, 769-P-HOTAIR, 786-0, and Kert-3 ) were maintained in vitro. The expression of HOTAIR mRNA was determined by quantitative real-time PCR and cell migration was measured by transwell migration assay. The effects of different concentrations of curcumin (0 to 80 μmol/L) on cell proliferation was determined by the CCK-8 assay and influence of non-toxic levels (0 to 10 μM) on the migration of RCC cells was also determined.. Comparison of the 5 cell lines indicated a correlation between HOTAIR mRNA expression and cell migration. In particular, the migration of 769-P-HOTAIR cells was significantly higher than that of 769-P-vector cells. Curcumin at 2.5-10 μM had no evident toxicity against RCC cells, but inhibited cell migration in a concentration-dependent manner.. HOTAIR expression is correlated with the migration of RCC cells, and HOTAIR may be involved in the curcumin-induced inhibition of RCC metastasis.

Topics: Carcinoma, Renal Cell; Cell Line, Tumor; Cell Movement; Cell Proliferation; Curcumin; Gene Expression Regulation, Neoplastic; Humans; Kidney Neoplasms; Neoplasm Invasiveness; Neoplasm Metastasis; RNA, Long Noncoding

Topics: Animals; Carcinoma, Renal Cell; Curcumin; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Kidney Neoplasms; Male; Vascular Endothelial Growth Factor A

The Janus kinase-2 (Jak2)-signal transducer and activator of transcription-3 (STAT3) pathway is critical for promoting an oncogenic and metastatic phenotype in several types of cancer including renal cell carcinoma (RCC) and melanoma. This study describes two small molecule inhibitors of the Jak2-STAT3 pathway, FLLL32 and its more soluble analog, FLLL62. These compounds are structurally distinct curcumin analogs that bind selectively to the SH2 domain of STAT3 to inhibit its phosphorylation and dimerization. We hypothesized that FLLL32 and FLLL62 would induce apoptosis in RCC and melanoma cells and display specificity for the Jak2-STAT3 pathway. FLLL32 and FLLL62 could inhibit STAT3 dimerization in vitro. These compounds reduced basal STAT3 phosphorylation (pSTAT3), and induced apoptosis in four separate human RCC cell lines and in human melanoma cell lines as determined by Annexin V/PI staining. Apoptosis was also confirmed by immunoblot analysis of caspase-3 processing and PARP cleavage. Pre-treatment of RCC and melanoma cell lines with FLLL32/62 did not inhibit IFN-γ-induced pSTAT1. In contrast to FLLL32, curcumin and FLLL62 reduced downstream STAT1-mediated gene expression of IRF1 as determined by Real Time PCR. FLLL32 and FLLL62 significantly reduced secretion of VEGF from RCC cell lines in a dose-dependent manner as determined by ELISA. Finally, each of these compounds inhibited in vitro generation of myeloid-derived suppressor cells. These data support further investigation of FLLL32 and FLLL62 as lead compounds for STAT3 inhibition in RCC and melanoma.

Topics: Antineoplastic Agents; Apoptosis; Carcinoma, Renal Cell; Cell Line, Tumor; Curcumin; Gene Expression Regulation, Neoplastic; Humans; Interferon-gamma; Janus Kinase 2; Leukocytes, Mononuclear; Melanoma; Molecular Docking Simulation; Phosphorylation; Protein Multimerization; Pyrans; Signal Transduction; Solubility; STAT3 Transcription Factor; Vascular Endothelial Growth Factor A

Curcumin, a natural, biologically active compound extracted from rhizomes of Curcuma species, has been shown to possess potent anti-inflammatory, anti-tumor and anti-oxidative properties. The mechanism by which curcumin initiates apoptosis remains poorly understood. In the present report we investigated the effect of curcumin on the activation of the apoptotic pathway in human renal Caki cells. Treatment of Caki cells with 50 microM curcumin resulted in the activation of caspase 3, cleavage of phospholipase C-gamma1 and DNA fragmentation. Curcumin-induced apoptosis is mediated through the activation of caspase, which is specifically inhibited by the caspase inhibitor, benzyloxycarbony-Val-Ala-Asp-fluoromethyl ketone. Curcumin causes dose-dependent apoptosis and DNA fragmentation of Caki cells, which is preceded by the sequential dephosphorylation of Akt, down-regulation of the anti-apoptotic Bcl-2, Bcl-XL and IAP proteins, release of cytochrome c and activation of caspase 3. Cyclosporin A, as well as caspase inhibitor, specifically inhibit curcumin-induced apoptosis in Caki cells. Pre-treatment with N-acetyl-cysteine, markedly prevented dephosphorylation of Akt, and cytochrome c release, and cell death, suggesting a role for reactive oxygen species in this process. The data indicate that curcumin can cause cell damage by inactivating the Akt-related cell survival pathway and release of cytochrome c, providing a new mechanism for curcumin-induced cytotoxicity.

Topics: Antineoplastic Agents; Apoptosis; bcl-2-Associated X Protein; bcl-X Protein; Blotting, Western; Carcinoma, Renal Cell; Caspases; Curcumin; Cytochrome c Group; Down-Regulation; Enzyme Activation; Enzyme Inhibitors; Free Radical Scavengers; Gene Expression Regulation, Neoplastic; Humans; Inhibitor of Apoptosis Proteins; Kidney Neoplasms; Mitochondria; Poly(ADP-ribose) Polymerases; Protein Serine-Threonine Kinases; Proteins; Proto-Oncogene Proteins; Proto-Oncogene Proteins c-akt; Proto-Oncogene Proteins c-bcl-2; Reactive Oxygen Species; Reverse Transcriptase Polymerase Chain Reaction; RNA, Messenger; Tumor Cells, Cultured