Overcoming sunitinib resistance with tocilizumab in renal cell carcinoma: Discordance between in vitro and in vivo effects.

Sunitinib is one of the first-line multi-tyrosine kinase inhibitors for metastatic renal cell carcinoma, and resistance to sunitinib continues to be a limiting factor for the successful treatment. As interleukin-6 (IL-6) is overexpressed in sunitinib-resistant cells, the purpose of this study was to explore the potential of IL-6 inhibition with tocilizumab, an IL-6 receptor inhibitor, to overcome resistance. In vitro, two sunitinib-resistant renal cell carcinoma cell lines (Caki-1 and SN12K1) were treated with tocilizumab. A mouse subcutaneous xenograft model was also used. Cell viability was studied by MTT assay, and apoptosis by morphology and ApopTag. Expression of IL-6, vascular endothelial growth factor (VEGF), and Bcl-2 was analyzed by qPCR. In vitro, tocilizumab induced significant cell death, and reduced the expression of IL-6, VEGF, and Bcl-2 in sunitinib-resistant cells. However, the in vitro findings could not be successfully translated in vivo, as tocilizumab did not decrease the growth of the tumors.

FCX, an arylidene derivative, induces apoptosis in androgen receptor-selective prostate cancer cells.

CONTEXT: Rational screening of arylidene derivatives for biological activities has resulted in many lead molecules with anticancer properties with effective therapeutic window. AIMS: In the current study, FCX, an arylidene derivative, was screened for anticolon and prostate cancer activity. SETTINGS AND DESIGN: Prostate and colon cancer cell lines were used to check the FCX effect on proliferation, apoptosis, and mechanism of drug action. SUBJECTS AND METHODS: LNCaP, PC-3, HCT-8, and HT-29 cells were treated with various concentrations of the FCX. MTT assay was performed to check proliferation, propidium iodide and Hoechst dual staining for DNA fragmentation, and Annexin V binding assay for apoptosis, and cell cycle assay was done using flow cytometry. Functional androgen-mutated receptor cells were used mechanistic pathway elucidation. STATISTICAL ANALYSIS USED: A minimum of three individual replicates at different time periods were taken as mean value. The data were expressed in mean ± standard deviation. Student's t-test and one-way ANOVA were used to assess the statistical difference between the groups. RESULTS: FCX inhibited proliferation of prostate cancer cell lines in a dose-dependent manner with more selectivity toward LNCaP cells. Nuclear fragmentation and dose-dependent increase in Annexin V-positive LNCaP cells revealed apoptosis. Cell cycle G2/M phase arrest along with sub-G0/G1 population augmented the antiproliferative observations. Addition of FCX in the presence of estradiol, testosterone, and dehydroepiandrosterone, LNCaP cells markedly caused a dose-dependent increase in cell proliferation indicating the compound activity to be facilitated through androgen receptor pathway. CONCLUSIONS: Together with the results, it is evident that FCX has a wide therapeutic window in the in vitro inhibition of the prostate cancer cells mediated by hormone-dependent effects.

Secondary Metabolites of Saussurea costus Leaf Extract Induce Apoptosis in Breast, Liver, and Colon Cancer Cells by Caspase-3-Dependent Intrinsic Pathway.

BACKGROUND: Apoptosis, a major form of programmed cell death, plays a vital role in regulating tissue development and maintenance of homeostasis in eukaryotes. Apoptosis can occur via a death receptor-dependent extrinsic or a mitochondrial-dependent intrinsic pathway and can be induced by various chemotherapeutic agents. In this study, the anticancer activity of Saussurea costus and its mode of intervention in human cancer cells of breast, colon, and liver were investigated. RESULTS: In this study, the bioactives of S. costus leaves were extensively extracted in five solvents of different polarity. The cytotoxicity and anticancer effect of the extracted secondary metabolites were investigated against breast (MCF-7), liver (HepG2), and colon (HCT116) cancer cell lines using a Sulphorhodamine B (SRB) assay. Secondary metabolites extracted using hexane, methanol, ethyl acetate, and chloroform had the highest cytotoxicity and thus the greatest anticancer effect on all the cancer cell lines tested (IC50; ranging from 0.25 to 2.5 µg/ml), while butanol was comparatively less active (IC50; ranging from 23.2 to 25.5 µg/ml). Further investigation using DNA flow cytometry and fluorescent microscopy revealed that the extract arrested the cells in the G1 phase of cell cycle and induced apoptosis. Furthermore, the elevated expression level of proapoptotic proteins and decreased expression level of antiapoptotic proteins confirmed that the intrinsic (mitochondrial) pathway was involved in mediating the apoptosis of cancer cells upon treatment with S. costus extract. These results altogether suggest that S. costus could be a potential anticancer agent. CONCLUSION: These results suggest that the S. costus extract is the potential source of the secondary metabolites that could be used as anticancer agent to treat diverse cancers of breast, colon, and liver.

Chamomile and oregano extracts synergistically exhibit antihyperglycemic, antihyperlipidemic, and renal protective effects in alloxan-induced diabetic rats.

The bio-activities of separate Matricaria chamomilla (chamomile) and Origanum vulgare (oregano) are well studied; however, the combined effects of both natural products in animal diabetic models are not well characterized. In this study, alloxan-induced male albino rats were treated with single dose aqueous suspension of chamomile or oregano at dose level of either 150 or 300 mg/kg body mass or as equal parts as combination by stomach tube for 6 weeks. After treatment, blood samples were assessed for diabetic, renal, and lipid profiles. Insulin, amylase activity, and diabetic renal apoptosis were further evaluated. Treatment with higher dose of the extracts (300 mg/kg) as individual or as mixture of low doses (150 mg/kg of both the extracts) had significant mass gain, hypoglycemic effect (p ≤ 0.05) with decreased amylase activity and increased serum insulin levels. Restoration of renal profile, lipid profile with increase in HDL-c (p ≤ 0.05) along with reversal of pro-apoptotic Bax and anti-apoptotic Bcl-2 were well observed with 300 mg/kg mixture, showing synergistic activity of the extracts compared with individual low dose of 150 mg/kg. Collectively, our results indicate that combination of chamomile and oregano extracts will form a new class of drugs to treat diabetic complications.

A Novel, Potent, Small Molecule AKT Inhibitor Exhibits Efficacy against Lung Cancer Cells In Vitro.

PURPOSE: Anomalies of Akt regulation, including overexpression in lung cancer, impart resistance to conventional chemotherapy and radiation, thereby implicating this kinase as a therapeutic intervention point. A novel scaffold of Akt inhibitors was developed through virtual screening of chemical databases available at Birla Institute of Technology and Science, Pilani, Hyderabad, based on docking studies using Maestro. A benzothienopyrimidine derivative (BIA-6) was identified as a potential lead molecule that inhibited Akt1 enzyme activity with an IC50 of 256 nM. MATERIALS AND METHODS: BIA-6 was tested for in vitro Akt1 inhibition using a fluorescence resonance energy transfer kit. Anti-proliferative activity was tested in NCI-H460, A549, NCI-H1975, and NCI-H2170 cell lines. The effect of the compound on p-Akt (S(473)) was estimated. RESULTS: BIA-6 allosterically caused a dose dependent reduction of growth of cell lines with a half maximal growth inhibition (GI50) range of 0.49 µM to 6.6 µM. Cell cycle analysis indicated that BIA-6 caused a G1 phase arrest at < 100 nM but led to apoptosis at higher doses. BIA-6 also exhibited synergism with standard chemotherapeutic agents. CONCLUSION: BIA-6 is a novel, allosteric Akt inhibitor with potent anti-cancer activity in lung cancer cell lines, that effectively blocks the phosphoinositide-3 kinase/Akt pathway with a high margin selectivity towards normal cells.