NCI-H460 Non-small Cell Lung Cancer Research Articles

Antitumor activity of IHL-305, a novel pegylated liposome containing irinotecan, in human xenograft models

The antitumor effect of IHL-305, a novel pegylated liposome containing irinotecan, was investigated in human xenograft models. After subcutaneous transplantation of several human cancer cell lines (colorectal, non-small cell lung, small cell lung, prostate, ovarian and gastric cancer cells) to nude mice, IHL-305 or CPT-11 was administered intravenously 3 times at 4-day intervals. In all xenograft models tested, IHL-305 showed superior antitumor activity to that of CPT‑11 and a comparable tumor-growth-inhibitory effect at one-eighth or less of the dose of CPT-11, even against HT-29 colorectal and NCI-H460 non-small cell lung cancer cell lines, which show intrinsic resistance to CPT-11. A single injection or 2 injections of IHL-305 on several dosing schedules also resulted in a significant antitumor effect compared to that of vehicle control in a dose-dependent manner and showed comparable antitumor activity at about one-fifth the dose of the maximum tolerated dose of CPT-11. The analysis of the concentrations of irinotecan and SN-38, an active metabolite of CPT-11, in plasma and tumors revealed that irinotecan was maintained at high concentrations, and the prolonged presence of SN-38 in plasma and tumors in IHL-305 treated mice compared with CPT-11-treated mice. Therefore, the stronger tumor inhibitory effect of IHL-305, as compared to CPT-11, was associated with the difference in the concentration of irinotecan in plasma or tumors after each agent was administered and with the maintainance of a higher concentration of SN-38. These results indicate that IHL-305 demonstrated superior antitumor activity against a wide range of tumors at lower doses than CPT-11.

PIM1-Activated PRAS40 Regulates Radioresistance in Non-small Cell Lung Cancer Cells through Interplay with FOXO3a, 14-3-3 and Protein Phosphatases

Resistance of cancer cells to ionizing radiation plays an important role in the clinical setting of lung cancer treatment. To date, however, the exact molecular mechanism of radiosensitivity has not been well explained. In this study, we compared radioresistance in two types of non-small cell lung cancer (NSCLC) cells, NCI-H460 and A549, and investigated the signaling pathways that confer radioresistance. In radioresistant cells, exposure to radiation led to overexpression of PIM1 and reduction of protein phosphatases (PP2A and PP5), which induced translocation of PIM1 into the nucleus. Increased nuclear PIM1 phosphorylated PRAS40. Consequently, pPRAS40 made a trimeric complex with 14-3-3 and AKT-activated pFOXO3a, which then moved rapidly to the cytoplasm. Cytoplasmic retention of FOXO3a was associated with downregulation of proapoptotic genes and possibly radioresistance. On the other hand, no suppressive effect of radiation on protein phosphatases was detected and, concomitantly, protein phosphatases downregulated PIM1 in radiosensitive cells. In this setting, PIM1-activated pPRAS40, AKT-activated pFOXO3a, and their complex formation with 14-3-3 could be key regulators of the radiation-induced radioresistance in NSCLC cells.

Inhibition of cell motility and invasion by HangAmDan-B in NCI-H460 human non-small cell lung cancer cells

Correlation between inhibition of cell motility and anti-invasive activity by the water extract of HangAmDan-B (HAD-B), a crude extract of eight Korean medicinal animals and plants, in NCI-H460 human non-small cell lung cancer (NSCLC) cells was investigated. Within the concentrations that were not cytotoxic, HAD-B induced significant concentration-dependent inhibition of cell motility and invasiveness of NCI-H460 cells. Treatment with HAD-B resulted in dose-dependent inhibition of the activities of matrix metallo-proteinase (MMP)-2 and MMP-9, and this was correlated with a decrease in expression of their mRNA and proteins, and upregulation of tissue inhibitors of metalloproteinase (TIMP)-1 and TIMP-2 expression. Anti-invasive activity of HAD-B was also found to be associated with increased tightness of the tight junction (TJ), as demonstrated by an increase in transepithelial electrical resistance. In addition, the present results indicated that treatment with HAD-B resulted in repression of the levels of claudin family members, which are major components of TJs that play a key role in control and selectivity of para-cellular transport. Although further studies are needed, findings from the present study indicate that TJs and MMPs are critical targets of HAD-B-induced anti-invasiveness in NCI-H460 NSCLC cells.

Specific β-Tubulin Isotypes Can Functionally Enhance or Diminish Epothilone B Sensitivity in Non-Small Cell Lung Cancer Cells

Epothilones are a new class of microtubule stabilizing agents with promising preclinical and clinical activity. Their cellular target is β-tubulin and factors influencing intrinsic sensitivity to epothilones are not well understood. In this study, the functional significance of specific β-tubulin isotypes in intrinsic sensitivity to epothilone B was investigated using siRNA gene knockdown against βII-, βIII- or βIVb-tubulins in two independent non-small cell lung cancer (NSCLC) cell lines, NCI-H460 and Calu-6. Drug-treated clonogenic assays showed that sensitivity to epothilone B was not altered following knockdown of βII-tubulin in both NSCLC cell lines. In contrast, knockdown of βIII-tubulin significantly increased sensitivity to epothilone B. Interestingly, βIVb-tubulin knockdowns were significantly less sensitive to epothilone B, compared to mock- and control siRNA cells. Cell cycle analysis of βIII-tubulin knockdown cells showed a higher percentage of cell death with epothilone B concentrations as low as 0.5 nM. In contrast, βIVb-tubulin knockdown cells displayed a decrease in epothilone B-induced G2-M cell cycle accumulation compared to control siRNA cells. Importantly, βIII-tubulin knockdowns displayed a significant dose-dependent increase in the percentage of apoptotic cells upon treatment with epothilone B, as detected using caspase 3/7 activity and Annexin-V staining. Higher concentrations of epothilone B were required to induce apoptosis in the βIVb-tubulin knockdowns compared to control siRNA, highlighting a potential mechanism underlying decreased sensitivity to this agent. This study demonstrates that specific β-tubulin isotypes can influence sensitivity to epothilone B and may influence differential sensitivity to this promising new agent.

Abstract 700: ICAM-3 endows anti-cancer drug resistance against microtubule-damaging reagents via modulation of caspases activities and Bcl-2

Abstract We have previously reported that intercellular adhesion molecule-3 (ICAM-3) is associated with various cancer cell physiologic responses including developing cellular radio-resistance. In this report, we studied whether ICAM-3 exerts an additional effect on development of resistance against anti-cancer drug because drug/radiation resistance of cancer usually displays cross-resistance. We treated several anti-cancer drugs including, paclitaxel (Ptxl), 5-fourouracil (5-FU), and etoposide (Eto), to an ICAM-3 over-expressing stable transfectant or empty vector- transfected control NCI-H1299 non-small cell lung cancer (NSCLC) cell line (p53 and PTEN null cell). Ratios of cell survival against each drug were detected with microculture tetrazolium (MTT) assay. ICAM-3 stable transfectants showed less cell death compared with empty vector-transfected cells by Ptxl treatment. The ICAM-3 stable transfectants also showed a resistance against cell death induced by vincristine (VCS), another microtubule-damaging reagent. In clonogenic assay and cell counting assay, we also observed significant drug-resistance against microtubule-damaging reagents in ICAM-3 stable transfectant cell line. Ptxl/VCS-treated control control transfectant cells showed more apoptotic cell death and activation of caspase-3/-8 than those of ICAM-3 stable transfectant cell line at 96 hour after drugs treatments. Blockage of p44/42 MAPkinase and PI3-kinase/Akt pathway by treatment of pharmaceutical inhibitors increased Ptxl/VCS-induced apoptotic cell death. However, in same condition, ICAM-3 stable transfectant cell line showed relatively less cell death. We also detected ICAM-3 inhibited Ptxl/VCS-induced degradation of mitochondrial anti-apoptotic molecules including Bcl-2, Bcl-XL, and Mcl-1 in dose-dependent manner. These results indicate that ICAM-3 endowed drug-resistance of cancer cells against microtubule-damaging reagent via modulation of apoptosis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 700. doi:10.1158/1538-7445.AM2011-700

Synthesis of the new ring system pyrrolizino[2,3- b]indol-4(5 H)-one

Derivatives of the new ring system pyrrolizino[2,3- b]indol-4(5 H)-one were prepared in four steps starting from substituted benzonitriles bearing a functionalized amino group in the adjacent position. The unsubstituted- and the dimethoxy-pyrrolizinoindolones 5a and 5b exhibited modest activity against the HL-60(TB) human leukemia cell line, whereas the N-methylated dimethoxy-pyrrolizinoindolone 6b showed to be selective against MOLT-4 leukemia, A549/ATCC, HOP-92, and NCI-H460 non-small cell lung cancer, and CAKI-1 renal cancer cell lines.

Novel bis(thiosemicarbazones) of the 3,5-diacetyl-1,2,4-triazol series and their platinum(ii) complexes: chemistry, antiproliferative activity and preliminary nephrotoxicity studies

The preparation and characterization of three novel (4)N-monosubstituted bis(thiosemicarbazone) ligands of 3,5-diacetyl-1,2,4-triazol series and their dinuclear platinum complexes are described. The crystal and molecular structure of the [Pt(μ-H(3)L(3))](2) complex derived of 3,5-diacetyl-1,2,4-triazol bis((4)N-p-tolylthiosemicarbazone), H(5)L(3), has been resolved by single crystal X-ray diffraction. The ligands coordinate, in an asymmetric dideprotonate form, to the platinum ions in a tridentate fashion (NNS) and S-bridging bonding modes. Thus the molecular units of the platinum complexes are stacked as dimers. The new compounds synthesized have been evaluated for antiproliferative activity in vitro against NCI-H460, A2780 and A2780cisR human cancer cell lines. The cytotoxicity data suggest that these compounds may be endowed with important antitumour properties since are capable of not only circumventing cisplatin resistance in A2780cisR cells but also exhibit high antiproliferative activity in human non-small cell lung cancer NCI-H460 cells. The interactions of these compounds with calf thymus DNA was investigated by UV-vis absorption and a nephrotoxic study, in LLC-PK1 cells, has also been carried out.

A mathematical framework for separating the direct and bystander components of cellular radiation response

A mathematical model for fractional tumor cell survival was developed incorporating components of cell killing due to direct radiation interactions and bystander signals resulting from non-local dose deposition. Material and methods. Three possible mechanisms for signal production were tested by fitting predictions to available experimental results for tumor cells (non-small cell lung cancer NCI-H460 and melanoma MM576) exposed to gradient x-ray fields. The parameter fitting allowed estimation of the contribution of bystander signaling to cell death (20–50% for all models). Separation of the two components of cell killing allowed determination of the α and β parameters of the linear-quadratic model both with and without the presence of bystander signaling. Results and discussion. For both cell lines, cell death from bystander signaling and direct radiation interactions were comparable. For NCI-H460 cells, the values for α and β were 0.18 Gy−1 and 0.10 Gy−2 respectively when direct and bystander effects were combined, and 0.053 Gy−1 and 0.061 Gy−2 respectively when the signaling component was removed. For MM576, the corresponding respective values were 0.09 Gy−1 and 0.011 Gy−2 for the combined response, and 0.014 Gy−1 and 0.002 Gy−2 for the isolated direct radiation response. The bystander component in cell death was found to be significant and should not be ignored. Further experimental evidence is required to determine how these results translate to the in vivo situation where tumor control probability (TCP) models that currently assume cellular independence may need to be revised.

Retracted] Screening and identification of a peptide specifically targeted to NCI-H1299 cells from a phage display peptide library

Ligands that are capable of binding to tumor cell surface biomarkers specifically used in the early diagnosis of cancer and targeted drug delivery in cancer chemotherapy have been extensively investigated. Phage display technology has been demonstrated to be a powerful tool in this field. In this study, the non-small cell lung cancer NCI-H1299 and the normal lung small airway epithelial cell lines were used for subtractive screening in vitro with a phage display 12-peptide library. After three rounds of panning, there was an obvious enrichment in the phages specifically binding to the NCI-H1299 cells, and the output/input ratio of phages increased approximately 875-fold (from 0.4x104 to 3.5x106). A group of peptides capable of binding specifically to the NCI-H1299 cells was obtained, and the affinity of these peptides to bind to the targeted cells and tissues was studied. Through cell-based ELISA, immunocytochemical staining, immunohistochemical staining and immunofluorescence, an M13 phage was isolated and identified from the above screenings, and a synthetic peptide, ZT-1 (sequence QQMHLMSYAPGP), corresponding to the sequence of the surface protein of the M13 phage, was demonstrated to be capable of binding to the tumor cell surfaces of NCI-H1299 and A549 cells and biopsy specimens, but not to normal lung tissue samples, other cancer cells, or non-tumor adjacent lung tissues. In conclusion, the peptide ZT-1 may be a potential candidate biomarker ligand that can be used for targeted drug delivery in lung cancer therapy.

Abstract 5513: Synergistic antitumor activity of NK012, a micelle-forming macromolecular prodrug of SN-38, combined with platinum compounds in human cancer xenograft models

Abstract Irinotecan (CPT-11) is clinically used to treat various tumors, but low enzymatic conversion to its active metabolite, SN-38, limits its therapeutic effect. NK012, a micelle-forming macromolecular prodrug of SN-38, accumulates in tumor tissue and gradually releases SN-38 in enzyme-independent manner. NK012 showed much stronger growth inhibitory effects than CPT-11 at maximum tolerated dose (MTD) against all tested xenografted human tumors. Furthermore, NK012 showed much stronger antitumor activities than other cytotoxic agents clinically used for cancer treatment (taxanes, doxorubicin, carboplatin etc.). Here, we report combination antitumor effects of NK012 with platinum compounds in human breast cancer, non-small cell lung cancer, colorectal cancer and hepatocellular cancer xenografts in nude mice. The dose of NK012 was set at 1.9-3.8 mg/kg/day to be sub-optimum for complete regression depending on the cell line. NK012 and carboplatin were administered by q7dx3. Although both of NK012 and carboplatin were ineffective as single agent (minimum T/C values >50%), their combination was effective (minimum T/C value = 8%) to cause tumor regression in MC-05-JCK breast cancer. In MC-05-JCK breast cancer, the TGDs (Tumor Growth Delay; tumor tripling time over control group delayed by treatment / tumor tripling time of control group × 100) by NK012 1.9 mg/kg/day, carboplatin 50 mg/kg/day (67% of MTD), and their combination were 41%, 29%, and 286%, respectively. In NCI-H460 non-small cell lung cancer, the TGDs by NK012 3.8 mg/kg/day, carboplatin 75 mg/kg/day (MTD), and their combination were 90%, 71%, and 403%, respectively. In Co-3 colorectal cancer, the TGDs by NK012 3.8 mg/kg/day, carboplatin 75 mg/kg/day, and their combination were 358%, 97%, and >489%, respectively. Thus, combination of NK012 with carboplatin showed remarkably synergistic effects, and it didn't accompany toxicity exacerbation. Similarly, combination of NK012 with cisplatin exhibited remarkable synergistic effects in Li-07-JCK hepatocellular cancer. The TGDs by NK012 3.8 mg/kg, one shot, cisplatin 10 mg/kg, one shot, and their combination were 58%, 136%, and 455%, respectively. These results indicate that NK012 and platinum compounds combination regimen would be effective for treatment of patients with solid tumors including breast, non-small cell lung, colorectal and hepatocellular carcinomas. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 5513.

Chemistry, antiproliferative activity and low nephrotoxicity of 3,5-diacetyl-1,2,4-triazol bis(4N-thiosemicarbazone) ligands and their platinum(ii) complexes

The preparation and characterization of 3,5-diacetyl-1,2,4-triazol bis(4,4-dimethylthiosemicarbazone) ligand, H(3)L(1), and its dinuclear platinum complex [Pt(mu-HL(1))](2) is described. The crystal and molecular structure of the platinum complex has been resolved by single crystal X-ray diffraction. The ligands coordinate, in an asymmetric dideprotonate form, to the platinum ions in a tridentate fashion (NNS) and S-bridging bonding modes. Thus the molecular units of the platinum complexes are stacked as dimers. The new compounds synthesized together with the analogous monosubstituted ligand 3,5-diacetyl-1,2,4-triazol bis(4-methylthiosemicarbazone) (H(5)L(2)) and its dinuclear platinum(ii) complex [Pt(mu-H(3)L(2))](2) have been evaluated for antiproliferative activity in vitro against NCI-H460, A2780 and A2780cisR human cancer cell lines. The cytotoxicity data suggest that these compounds may be endowed with important antitumor properties, especially H(3)L(1) and [Pt(mu-H(3)L(2))](2) since they not only circumvent cisplatin resistance in A2780cisR cells but also exhibit high antiproliferative activity in human non-small cell lung cancer NCI-H460 cells. Subsequent nephrotoxic study, in LLC-PK1 cells, show that the four compounds investigated exhibit very low nephrotoxicity with respect to cisplatin.

ICAM-3 enhances the migratory and invasive potential of human non-small cell lung cancer cells by inducing MMP-2 and MMP-9 via Akt and CREB

We have previously reported that intercellular adhesion molecule-3 (ICAM-3) is associated with an increase of cellular radio-resistance and cancer cell proliferation. In this study, we hypothesized that ICAM-3 has an additional effect on cancer cell migration and invasion because molecules induced by ICAM-3 are known as regulators of cell migration and invasion. To examine this hypothesis, we used NCI-H1299 non-small cell lung cancer (NSCLC) cell line (p53 and PTEN null cell) and constructed an ICAM-3-over-expressing stable transfectant, which exhibited increased cell migration and invasion. The increased migration and invasion resulted from up-regulation of expression and activities of MMP-2 and MMP-9. ICAM-3 also increased Akt phosphorylation, which caused an increase in cellular migration/invasion and MMP activities. Activity of several transcriptional factors located downstream in the Akt pathway was also tested, and constitutive activation of adenosine 3', 5'-monophosphate response element-binding protein (CREB) by ICAM-3 was detected. Blockage of the Akt pathway attenuated CREB activation, and a decrease in CREB expression reduced cellular migration/invasion and activity of MMPs. This result indicates that CREB functions in the signaling pathway between Akt and MMP. We also showed ICAM-3-induced cell migration and invasion in NCI-H460 NSCLC cells (wild-type p53 and PTEN cell) through the same signaling pathway. Taken together, our findings suggest that ICAM-3 stimulates cancer cell migration/invasion via ICAM-3/Akt/CREB/MMP pathway regardless of p53 and PTEN status, and this reflects the possibility that ICAM-3 could be considered as a candidate for anti-cancer drug development and as a cancer diagnostic marker.

Screening and identification of a peptide specifically targeted to NCI-H1299 cells from a phage display peptide library

Ligands that are capable of binding to tumor cell surface biomarkers specifically used in the early diagnosis of cancer and targeted drug delivery in cancer chemotherapy have been extensively investigated. Phage display technology has been demonstrated to be a powerful tool in this field. In this study, the non-small cell lung cancer NCI-H1299 and the normal lung small airway epithelial cell lines were used for subtractive screening in vitro with a phage display 12-peptide library. After three rounds of panning, there was an obvious enrichment in the phages specifically binding to the NCI-H1299 cells, and the output/input ratio of phages increased approximately 875-fold (from 0.4x104 to 3.5x106). A group of peptides capable of binding specifically to the NCI-H1299 cells was obtained, and the affinity of these peptides to bind to the targeted cells and tissues was studied. Through cell-based ELISA, immunocytochemical staining, immunohistochemical staining and immunofluorescence, an M13 phage was isolated and identified from the above screenings, and a synthetic peptide, ZT-1 (sequence QQMHLMSYAPGP), corresponding to the sequence of the surface protein of the M13 phage, was demonstrated to be capable of binding to the tumor cell surfaces of NCI-H1299 and A549 cells and biopsy specimens, but not to normal lung tissue samples, other cancer cells, or non-tumor adjacent lung tissues. In conclusion, the peptide ZT-1 may be a potential candidate biomarker ligand that can be used for targeted drug delivery in lung cancer therapy.

Oxidative and endoplasmic reticulum stress signaling are involved in dehydrocostuslactone-mediated apoptosis in human non-small cell lung cancer cells

This study investigates the anticancer effect of dehydrocostuslactone (DHE), a medicinal plant-derived sesquiterpene lactone, on human non-small cell lung cancer cell lines, A549, NCI-H460 and NCI-H520. Our results show that DHE inhibits the proliferation of A549, NCI-H460 and NCI-H520 cells. DHE-induced apoptosis in both A549 and NCI-H460 cells. DHE triggered endoplasmic reticulum (ER) stress, as indicated by changes in cytosol-calcium levels, PKR-like ER kinase (PERK) phosphorylation, inositol requiring protein 1 (IRE1) and CHOP/GADD153 upregulation, X-box transcription factor-1 (XBP-1) mRNA splicing, and caspase-4 activation. The release of calcium triggered the production of ROS, which further enhances calcium overloading and subsequently activates p38, JNK and ERK1/2. Both IRE1 miRNA transfection and BAPTA-AM pretreatment inhibit DHE-mediated apoptosis, supporting the hypothesis that DHE induces cell death through ER stress. Importantly, a novel anticancer agent for the treatment of non-small cell lung cancer, and is supported by animal studies which have shown a dramatic 50% reduction in tumor size after 28 days of treatment. This study demonstrates that DHE may be a novel anticancer agent for the treatment of non-small cell lung cancer.

Transient RNA silencing of tissue factor pathway inhibitor-2 modulates lung cancer cell invasion

Tissue Factor Pathway Inhibitor-2 (TFPI-2) is a potent inhibitor of plasmin which activates metalloproteinases (MMPs) involved in extracellular matrix (ECM) degradation. Its secretion in ECM makes TFPI-2 a potential inhibitor to regulate tumour invasion and metastasis. Moreover, TFPI-2 is frequently downregulated, particularly in aggressive cancers. In this study, we silenced TFPI-2 in the NCI-H460 non-small cell lung cancer cell line and evaluated the role of TFPI-2 in cell invasion and its impact on MMPs expression. As the effects of siRNA are transient, the consequences of both gene silencing and restoration to normal expression could be studied kinetically in the same cells. We showed that TFPI-2 expression by NCI-H460 cells was effectively downregulated using specific small interfering RNA and this silencing was associated with an increase in the invasive potential of tumour cells while migration was not affected. We also showed that mRNA levels and protein expression of MMP-2, -3, -9, -14 were not influenced by TFPI-2 silencing. Moreover, the gelatinase activity of MMP-2 and MMP-9 was unmodified. In contrast, MMP-1 mRNA levels and protein were significantly and similarly increased in cells transfected with TFPI-2 siRNA. In conclusion, this study confirms that TFPI-2 downregulation can contribute to tumour invasion of lung cancer cells.

HSP90 inhibitor, DMAG, synergizes with radiation of lung cancer cells by interfering with base excision and ATM-mediated DNA repair

Inhibition of heat shock protein 90 (HSP90) leads to inappropriate processing of proteins involved in cell survival pathways. We found that HSP90 inhibitor, 17-(dimethylaminoethylamino)-17-demethoxygeldanamycin (DMAG), is synergistic with radiation for non-small cell lung cancer cell lines, NCI-H460 and A549. To establish the optimal schedule for this combination, cells were radiated before, after, or simultaneously with DMAG, and survival was scored by clonogenic assay. The sequence of DMAG administration was critical for synergy with radiation, and pretreatment for 16 h led to maximal synergy. Similar radiosensitization was observed in isogenic cells in which expression of wild-type p53 was silenced by RNA interference, although p53 loss rendered cells overall less radiosensitive. The mechanistic basis for synergy was studied by Western blotting, cell cycle analysis, alkaline comet assay, and direct measurement of the activities of key base excision repair enzymes. Regardless of schedule of administration, DMAG led to degradation of proteins involved in activation of cell survival pathways after radiation, which did not explain the differences in the schedule of administration observed in clonogenic assays. In addition to previously reported decrease in activation of ATM, pretreatment with DMAG blocked activation of base excision repair machinery and activity of key enzymes, apurinic/apyrimidinic endonuclease, and DNA polymerase-beta. Similarly, pretreatment with specific apurinic/apyrimidinic endonuclease inhibitor, CRT0044876, reproduced the effects of DMAG. Thus, administration of HSP90 inhibitors before radiation is critical for optimizing their use as radiosensitizers.

Effect of lumiracoxib on proliferation and apoptosis of human nonsmall cell lung cancer cells in vitro

Lumiracoxib is a highly selective cyclooxygenase-2 (COX-2) inhibitor with antiinflammatory, analgesic and antipyretic activities comparable with class specific drugs, but with much improved gastrointestinal safety. No studies have examined lumiracoxib for antitumorigenic activity on human nonsmall cell lung cancer cell lines in vitro or its possible molecular mechanisms. The antiproliferative effect of lumiracoxib alone or combined with docetaxol on A549 and NCI-H460 lines was assessed by 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. Drug-drug interactions were analyzed using the coefficient of drug interaction (CDI) to characterize the interactions as synergism, additivity or antagonism. Morphological changes were observed by acridine orange fluorescent staining. Extent of apoptosis was determined by flow cytometry. Lumiracoxib (15 - 240 micromol/L) has an inhibitory effect on the proliferation of A549 and NCI-H460 cell lines in concentration- and time-dependent manners with the IC50 values of 2597 micromol/L and 833 micromol/L, respectively. The synergistic effect was prominent when lumiracoxib (15 - 240 micromol/L) was combined with docetaxol (0.2 - 2 micromol/L) (CDI < 1). Fluorescent staining showed that lumiracoxib could induce apoptosis in A549 and NCI-H460 cells. Lumiracoxib treatment also caused an increase of the sub-G1 fraction in each cell line and resulted in an increase of G0/G1-phase cells and a decrease of S-phase cells. Lumiracoxib had antiproliferative effect on the human nonsmall cell lung cancer cell lines A549 and NCI-H460 and had a significant synergy with docetaxol, which may be related to apoptotic induction and cell cycle arrest.

Bipinnatins K–Q, Minor Cembrane-Type Diterpenes from the West Indian Gorgonian Pseudopterogorgia kallos: Isolation, Structure Assignment, and Evaluation of Biological Activities

An extensive chemical study of the secondary metabolites found in the crude organic extract of the gorgonian octocoral Pseudopterogorgia kallos has led to the isolation of seven new cembranolides, bipinnatins K-Q ( 2- 8), and one known compound, bipinnatin E ( 9). The molecular structures of compounds 2- 8, many of which contain unusual structural features, were assigned mainly by 2D NMR spectroscopic methods and X-ray crystallographic analysis. The discovery of compounds 2- 8 may lend support to previously proposed mechanisms for the biosynthesis of recently isolated bioactive natural products from the same gorgonian specimen. The in vitro cytotoxicity of bipinnatins 4, 6, and 7 against the NCI tumor cells MCF breast cancer, NCI-H460 non-small cell lung cancer, and SF-268 CNS cancer was evaluated. However, only bipinnatin Q ( 6) displayed significant cytotoxic activity. Some of the compounds isolated proved to be inhibitors of acetylcholine receptors.

PC-SPES down-regulates COX-2 via inhibition of NF-κB and C/EBPβ in non-small cell lung cancer cells

Aberrant expression of COX-2 occurs in many types of malignancies including colon and lung cancers, and is implicated in development and progression of cancer. The molecular mechanisms associated with aberrant expression of COX-2 in lung cancer cells remain to be fully elucidated. In this study, we found that non-small cell lung cancer (NSCLC) NCI-H520 and NCI-H460 cells constitutively expressed COX-2 and produced prostaglandin E2 (PGE2) as measured by Western blotting and enzyme-linked immunosorbent assay (ELISA), respectively. Reporter assays showed that transcriptional regulation of COX-2 was blunted when either the NF-IL6 (C/EBPbeta) or nuclear factor-kappaB (NF-kappaB) binding site in the COX-2 promoter was mutated, suggesting that C/EBPbeta and NF-kappaB transcription factors have an important role in aberrant expression of COX-2 in these lung cancer cells. In addition, the eight herbal mixture PC-SPES (Lot. 5431219) caused growth arrest and apoptosis of NCI-H520 and NCI-H460 cells in association with blockade of NF-kappaB and down-regulation of C/EBPbeta, resulting in down-regulation of COX-2 and PGE2 in these cells. On the other hand, PC-SPES up-regulated the level of C/EBPbeta in these cells. Taken together, C/EBPbeta and NF-kappaB may be promising molecular targets for COX-2 inhibition in lung cancer cells. PC-SPES might be useful in the adjuvant setting for the treatment of individuals with resected NSCLC as well as other types of cancer in which COX-2 is activated.

Sorafenib is efficacious and tolerated in combination with cytotoxic or cytostatic agents in preclinical models of human non-small cell lung carcinoma

Sorafenib tosylate (sorafenib, BAY 43-9006, Nexavar) is a multi-kinase inhibitor that targets tumor cell proliferation and angiogenesis. These studies evaluated the efficacy and tolerability of combinations of sorafenib plus agents used to treat non-small cell lung cancer (NSCLC) using preclinical models of that disease. Intravenous (iv) vinorelbine and interperitoneal (ip) cisplatin were administered intermittently (q4d x 3) in combination with sorafenib administered orally (po) once daily for 9 days starting on the same day as the standard agent. In studies with sorafenib and gefitinib, both agents were administered po daily for 10 days starting on the same day. Treatment in all studies was initiated against established sc tumors, and each study was conducted in duplicate. Efficacy was assessed as the delay in tumor growth to a specified size (TGD). Vinorelbine (6.7 mg/kg) and sorafenib (40 mg/kg) produced TGDs of 2.4 and 7.8 days, respectively, in the NCI-H460 NSCLC model. Combination therapy produced a 10.0-day TGD with no increase in toxicity. Combination therapy in the NCI-H23 NSCLC model with the highest evaluated dose levels of sorafenib plus cisplatin was well tolerated and produced TGDs equivalent to those produced by cisplatin alone. Lower dose levels of each agent produced approximately additive TGD's. Combination therapy in the A549 NSCLC model with sorafenib and gefitinib produced TGDs equivalent to that produced by sorafenib alone with no toxicity. Tumor growth in the MDA-MB-231 mammary tumor model, that contains mutations in signal transduction proteins downstream of the EGF receptor (the target of gefitinib) was also inhibited by sorafenib, but not by gefitinib. Concurrent administration of sorafenib and vinorelbine, cisplatin or gefitinib was at least as efficacious as the individual agents alone and was well tolerated. These results support the inclusion of sorafenib in clinical trials in NSCLC employing combinations of both cytotoxic and cytostatic agents.