Growth Of Human Carcinoma Cells Research Articles

Development of an antifungal drug loaded spinel ferrite nanocarrier with enhanced antifungal activity and superior anticancer effect against human lung carcinoma cells

Mg1–xCuxFe2O4 (x = 0, 0.1) nanoparticle was successfully synthesized by the sol-gel method. Synthesized Mg0.9Cu0.1Fe2O4 nanoparticle was coated with the soluble starch and then conjugated with the antifungal drug ketoconazole. The detailed microstructural and structural characterizations of the nanoparticles and drug-loaded nanosystem were carried out by analyzing FTIR, EDS patterns and XRD data employing Rietveld refinement. The average particle sizes of different samples were determined from SEM and TEM image analysis. The antifungal activities of Mg0.9Cu0.1Fe2O4 nanoparticles (NP) and drug-conjugated nanoparticles (NP-DC) were revealed by agar cup assay and minimum inhibitory concentration (MIC) study against Candida Sp. A significant zone of fungal inhibition was obtained in the NP sample, and the antifungal efficacy indicated that it can be a promising antifungal agent without any external drug. The zone of inhibition due to the NP-DC sample was larger than that of the pure drug ketoconazole. It revealed the significant enhancement of the efficacy of ketoconazole after its conjugation with the NP sample, which was confirmed by the MIC study. In the MIC study, it has been revealed that the NP-DC sample has a similar activity as 100wt % ketoconazole. But in the NP-DC sample, only 40 wt % ketoconazole was present. It confirms the significantly enhanced activity of pure drug after its conjugation with the NP sample. The NP-DC sample has also significant inhibitory activity against the growth of lung carcinoma cells (A549 cells) while it has no any significant toxic effect on the normal human WI38 cells (lung fibroblast cells) as indicated by MTT assay. The anti-cancer activity of the NP-DC sample is significantly higher than that of the pure drug ketoconazole. The ability of NP-DC to produce cellular ROS and induction of apoptosis has been confirmed to be the cause of the enhanced cytotoxic effect of the NP-DC sample against lung carcinoma cells. This significant enhancement of antifungal and anticancer efficacy indicates the formation of a new nanomedicine with a significant antifungal activity that can also inhibit the growth of human carcinoma cells with higher efficacy. Due to enhanced efficacy, a small amount of ketoconazole conjugated with NPs would be required for the treatment, which in turn, reduces the side effects of the drug and becomes more affordable to the patients. This new nanomedicine can also be used as a potential drug for cancer treatment.

Antiproliferative and apoptosis inducing effect of essential oil extracted from Cyrtomium fortumei (J.) Smith leaves.

Cyrtomium fortumei (J.) Smith is an endemic species in China, which has been proved to be an important Chinese herbal medicine. However, chemical composition and bioactivity of essential oil (EO) of C. fortumei (J.) Smith leaves remain unclear. In present study, we isolated EO from the plant by supercritical carbon dioxide extraction assay (SFE-CO2), and investigated on cancer cells MGC-803, MCF-7, BGC-823, Bcap-37, A375, and A549 in vitro by MTT assay. 26 compounds were identified by GC–MS analysis, and the EO showed significant antitumor activities against MGC-803, Bcap-37, and A549 cancer cell lines (IC50 values ranging from 0.15 to 0.24 mg/mL), and the activities of its main component were also studied. Subsequent fluorescence staining and flow cytometry analysis indicated that the EO could induce apoptosis in MGC-803, Bcap-37, and A549 cell lines, and the apoptosis ratios reached 26.44 % after 48 h of treatment at 0.15 mg/mL in MGC-803 cells. Caspase 3 activity in MGC-803 cells was also determined when the cells treated with the oil, and the activity of caspase 3 enzyme was increased compared to the control. This study suggests that the EO isolated from C. fortumei (J.) Smith could inhibit the growth of human carcinoma cells, and it could induce apoptosis of cancer cells.Electronic supplementary materialThe online version of this article (doi:10.1007/s00044-014-1244-1) contains supplementary material, which is available to authorized users.

Extraction optimisation and isolation of triterpenoids from Ganoderma lucidum and their effect on human carcinoma cell growth

The response surface methodology was used to optimise the extraction conditions of Ganoderma lucidum based on a Box–Behnken design. A quadratic model sufficiently simulated the response of ganoderic acid H with a determination coefficient (R2) of 0.98. The optimal condition for extracting triterpenoids was determined to be 100.00% ethanol at 60.22°C for 6.00 h, under which the yield of the reference triterpenoid ganoderic acid H increased from 0.88 to 2.09 mg/g powder. Following extraction, triterpenoid-enriched fraction was further isolated into 23 fractions, and 7 fractions were identified as ganoderic acids A, B, D, G, H and I and ganoderenic acid D. Of the seven triterpenoids, ganoderenic acid D was most cytotoxic with IC50 values of 0.14 ± 0.01, 0.18 ± 0.02 and 0.26 ± 0.03 mg/mL in Hep G2, Hela and Caco-2 cells, respectively. While ganoderic acids A, G and H were relatively non-cytotoxic. The variation of inhibitory effects for these triterpenoids was likely related to their chemical structures.

Discovery and antitumor activities of constituents from Cyrtomium fortumei(J.) Smith rhizomes

BackgroundCyrtomium fortumei (J.) Smith is an important Chinese herbal medicine because of its biological functions. However, systematic and comprehensive studies on the phytochemicals from Cyrtomium fortumei (J.) Smith and their bioactivity are limited.ResultsUsing the bioassay-guided technique, the ethyl acetate and n-BuOH extracts of the rhizomes of Cyrtomium fortumei (J.) Smith were shown to exhibit good antitumor activities, consequently leading to the isolation of 23 compounds. All compounds were isolated from the plant for the first time. The inhibitory activities of these compounds were investigated on tumor cells MGC-803, PC3, and A375 in vitro by MTT (thiazolyl blue tetrazolium bromide) assay, and the results showed that pimpinellin (3) had potent cytotoxic activities against the three cell lines, with the IC50 values of 14.4 ± 0.3 μM, 20.4 ± 0.5 μM, and 29.2 ± 0.6 μM, respectively. The mechanism of the antitumor action indicated that pimpinellin inhibited the growth of MGC-803 cells via the induction of tumor cell apoptosis, with apoptosis ratio of 27.44% after 72 h of treatment at 20 μM.ConclusionsThis study suggests that most of the compounds from the roots of Cyrtomium fortumei (J.) Smith could inhibit the growth of human carcinoma cells. Moreover, pimpinellin inhibited the growth of tumor cells via the induction of tumor cell apoptosis.

Antiproliferation and cell apoptosis inducing bioactivities of constituents from Dysosma versipellis in PC3 and Bcap-37 cell lines.

BackgroundRecently, interest in phytochemicals from traditional Chinese medicinal herbs with the capability to inhibit cancer cells growth and proliferation has been growing rapidly due to their nontoxic nature. Dysosma versipellis as Bereridaceae plants is an endemic species in China, which has been proved to be an important Chinese herbal medicine because of its biological activity. However, systematic and comprehensive studies on the phytochemicals from Dysosma versipellis and their bioactivity are limited.ResultsFifteen compounds were isolated and characterized from the roots of Dysosma versipellis, among which six compounds were isolated from this plant for the first time. The inhibitory activities of these compounds were investigated on tumor cells PC3, Bcap-37 and BGC-823 in vitro by MTT method, and the results showed that podophyllotoxone (PTO) and 4'-demethyldeoxypodophyllotoxin (DDPT) had potent inhibitory activities against the growth of human carcinoma cell lines. Subsequent fluorescence staining and flow cytometry analysis indicated that these two compounds could induce apoptosis in PC3 and Bcap-37 cells, and the apoptosis ratios reached the peak (12.0% and 14.1%) after 72 h of treatment at 20 μM, respectively.ConclusionsThis study suggests that most of the compounds from the roots of D. versipellis could inhibit the growth of human carcinoma cells. In addition, PTO and DDPT could induce apoptosis of tumor cells.

Stress hormone epinephrine promoting the growth of human hepatocellular carcinoma cells via β2-AR-mediated activation of ERK1/2

Objective To investigate the effect of the stress hormone epinephrine (EPI) on the growth of human Hepatocellular carcinoma (HCC) cells.Methods The effects of EPI on the growth of human HCC HepG2 and MHCC97H cells were investigated by using proliferation assay in correlation with α1-/β2-adrenergic receptors (α1-/β2-ARs),proliferative activity and signaling pathways of adenyl cyclase/protein kinase A (AC/PKA),mitogen-activated protein kinase/extracellular signal-regulated kinase 1/2 (MAPK/ERK1/2) and phosphatidylinositol-3-kinase/protein kinase B ( PI3 K/AKT/PKB).Results EPI significantly promoted the growth of HCC cells rather than human normal hepatic cells (L-02) in a dose-dependent and time-dependent manner (P ＜ 0.05 ).The maximal growth rate was presented at concentration of 10 μmol/L and 24-48 h [HepG2/(215 ±4)% and MHCC97H/(207 ± 10)%].In HepG2 and MHCC97H cells,α1-AR was reduced to 30% and 34%,and β2-AR was elevated to 331% and 309% of that in L-02,respectively.The selective β2-AR antagonist ICI 118551 efficiently attenuated the growth-promoting effect of EPI,and the β-AR agonist isoproterenol (ISO) exhibited a similar growth-promoting effect on HCC cells.The effect of ISO was efficiently attenuated either by ICI 118551 or the MAPK/ERK kinase 1/2 (MEK1/2) inhibitor U0126,but partially inhibited either by the PKA inhibitor H-89 or PI3K inhibitor LY294002.The phospho-ERK1/2 was transiently elevated by 3.49/3.02 folds in HepG2 and 3.15/2.73 folds in MHCC97H cells,which could be down-regulated either by the treatment of ICI 118551 or U0126.Conclusion β2-AR was over-expressed in both HepG2 and MHCC97H cells.EPI promoted the growth of HepG2 and MHCC97H cells mainly through the β2-AR-mediated activation of ERK1/2. Key words: Carcinoma,hepatocellular; Stress; Adrenergic receptor; Extracellular signalregulated kinase 1/2

Expression of laminin γ2 chain monomer enhances invasive growth of human carcinoma cells in vivo

Laminin gamma2 chain is a subunit of the heterotrimeric basement membrane protein laminin-332 (alpha3beta3gamma2). The gamma2 chain is highly expressed by human cancers at the invasion fronts and this expression correlates with poor prognosis of the cancers. Our previous study showed that the gamma2 chain is expressed as a monomer form in invading carcinoma cells. However, the role of the gamma2 protein in tumor invasion remains unknown. Here, we demonstrate that the monomeric gamma2 chain promotes invasive growth of human cancer cells in vivo. First, we analyzed regulatory factors for the gamma2 chain expression using 2 gastric carcinoma cell lines. It was found that tumor necrosis factor-alpha, by itself or in a combination with transforming growth factor-beta1, strongly induced the secretion of the monomeric gamma2 chain. In addition, epidermal growth factor families appeared to function as the gamma2 chain inducers in human cancers. Next, we established T-24 bladder carcinoma cell lines expressing the full-length or the short arm of the laminin gamma2 chain. When these cell lines were i.p. injected into nude mice, they produced larger tumors in the abdominal cavity and showed much stronger invasive growth onto the diaphragms than the control cell line. The gamma2-expressing T-24 cells often produced ascites fluid, but scarcely the control cells. In culture, the gamma2-expressing cells migrated through Matrigel more efficiently than the control cells. These findings imply that the gamma2 monomer is induced in human cancers by inflammatory and stromal cytokines and promotes their invasive growth in vivo.

Inhibitory effect of low molecular weight heparin on the growth and metastasis of human mammary carcinoma cells implanted in nude mice

Objective To study the inhibitory effect of low molecular weight heparin (LMWH) on the growth and metastasis of breast cancer (BC) cells in the MCF-7 nude mice models.Methods BC models were successfully established in 120 nude mice by implanting human MCF-7 cells,and randomly divided into 4 groups:chemotherapy group,LMWH group,endocrine group and normal saline (NS) group.During 4 weeks of treatment,the general physical state of the nude mice and the development of the tumors were observed.After 28 days,the model mice were sacrificed by taking off the cervical vertebra,and the pathological changes of the samples were observed and the expression of vascular endothelial growth factor (VEGF)and microvessel density(MVD)in the tumor samples was detected by immunohistochemicalmethod respectively.Results After 4 weeks of treatment,the expression levels of vascular endothelial growth factor (VEGF) and MVD in chemotherapy group,LMWH group and endocrine group were significantly lower than those in NS group(P<0.01),and they were superior to NS group in the aspects of tumor volume,chest wall erosion and lymph node metastasis.Among all these groups,the expression levels of VEGF and MVD in LMWH group were decreased markedly,but there Was no statistically significant difference.Conclusion LMWH Can inhibit the growth and metastasis of BC in the MCF-7 nude mice models. Key words: Breast carcinoma; Low molecular heparin; Vascular endothelial growth factor; Angiogenesis

Anticancer activity of subfractions containing pure compounds of Chaga mushroom (Inonotus obliquus) extract in human cancer cells and in Balbc/c mice bearing Sarcoma-180 cells

The Chaga mushroom (Inonotus obliquus) has been used in folk medicine to treat cancers. However, limited information exists on the underlying anticancer effects of the major component of I. obliquus in vivo. We hypothesize that the pure compounds (3β-hydroxy-lanosta-8,24-dien-21-al, inotodiol and lanosterol, respectively) separated from I. obliquus would inhibit tumor growth in Balbc/c mice bearing Sarcoma-180 cells (S-180) in vivo and growth of human carcinoma cells in vitro. To test this hypothesis, the growth inhibition of each subfraction isolated from I. obliquus on human carcinoma cell lines (lung carcinoma A-549 cells, stomach adenocarcinoma AGS cells, breast adenocarcinoma MCF-7 cells, and cervical adenocarcinoma HeLa cells) was tested in vitro. Then, after S-180 implantation, the mice were fed a normal chow supplemented with 0, 0.1 or 0.2 mg of subfraction 1, 2 or 3 per mouse per day. All of the subfractions isolated from I. obliquus showed significant cytotoxic activity against the selected cancer cell lines in vitro. Subfraction 1 was more active than subfraction 2 and subfraction 3 against the A549, AGS and MCF-7 cancer cell lines in vitro. In in vivo results, subfraction 1 isolated from I. obliquus at concentrations of 0.1 and 0.2 mg/mouse per day significantly decreased tumor volume by 23.96% and 33.71%, respectively, as compared with the control. Subfractions 2 and 3 also significantly inhibited tumor growth in mice bearing S-180 as compared with the control mouse tumor. Subfraction 1 isolated from I. obliquus showed greater inhibition of tumor growth than subfractions 2 and 3, which agrees well with the in vitro results. The results suggest that I. obliquus and its compounds in these subfractions isolated from I. obliquus could be used as natural anticancer ingredients in the food and/or pharmaceutical industry.

Fas-associated death domain protein enhance inhibitory effect of 5-fluorouracil on growth of human colorectal carcinoma cells

Objective To examine the sensitivity of human colorectal carcinoma cells to 5-fluorouracil treatment by stable transfection of extrinsic Fas-associated death domain protein(FADD) gene，both in vitro and in vivo，so as to investigate the feasibility of combination therapy of FADD gene and 5-fluorouracil in human colorectal carcinoma. Methods ①RT-PCR and Western blotting were used to detect the expressions of both mRNA and protein of FADD gene in SW480／FADD (stably transfected with FADD)，SW480／neo and SW480 cells.②After treatment with 5-fluorouracil as an apoptotic inducer，in vitro cell growth activities were investigated by MTT assay.Cell apoptosis and its rates were determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling(TUNEL)assay and flow cytometry of annexin V-FITC／PI staining.The expressions of caspase-8 and caspase-3 were examined by Western blotting. ③To examine the inhibitory effect of FADD gene combined with 5-fluorouracil, tumor xenograft model was prepared for in vivo study.Results ① Compared with SW480 and SW480/neo cells, FADD mRNA and protein levels of SW480/FADD cells were higher (P<0.05). ② Inhibitory rate of SW480/FADD cells was remarkably higher than SW480 and SW480/neo cells (P＜0.05 ). ③ Forty-eight hours after treatment with 5-fluorouracil (10 mg/L), the apoptotic rate of SW480/FADD cells was (33.3 ± 4.5)%, which was higher than SW480 [(13. 9 ± 3. 2)%3 and SW480/neo [(14. 1 ± 3. 4)%], with significant difference (P< 0.05). ④ Forty-eight hours after treatment with 5-fluorouracil (10 mg/L),procaspase-8 and procaspase-3 expressions of SW480 and SW480/neo cells were higher than SW480/FADD cells, whereas their cleaved caspase-8 and cleaved caspase-3 expressions were lower than SW480/FADD cells (P＜0. 05).⑤ In in vivo study, SW480/FADD cells increased the efficacy of fluorouracil-induced inhibition of tumor growth in nude mice. Conclusions Stable overexpression of FADD increases sensitivity of the cells to 5-fluorouracil and combination of FADD with 5-fluorouracil will he a promising alternative in colorectal cancer treatment. Key words: Colonic neoplasms; Fas-associated death domain protein; 5-Fluorouracil

Effects of transfected pIRES-p21(waf1)-p27(kip1) gene on the duplication of centrosomes and the proliferation of breast cancer cell line MCF-7

To explore the role of transfected pIRES-p21(waf1)-p27(kip1) gene on the centrosome duplication and cell proliferation of MCF-7, a breast cancer cell line. The pIRES-p21(waf1), pIRES-p27(kip1) and pIRES-p21(waf1)-p27(kip1) genes were transfected into the MCF-7 cells by lipofection. The effect on proliferation was evaluated by MTT assay and cell growth curve was drawn. The cell cycle was analyzed by flow cytometry. The centrosome duplication was detected by using indirect immunofluorescence microscopy. After transfected 24 hours, the p21(waf1) and p27(kip1) protein expressions were significantly increased as compared with untransfected MCF-7 cells (P < 0.01), and cell growth was obviously inhibited and resulted in an accumulation of cells in G(1) (P < 0.01), presenting that the proportion of cells in G(1) phase was obviously increased from(47.28 +/- 2.25)% to (69.52 +/- 3.21)% of p21(waf1) transfected cells, (60.83 +/- 3.02)% of p27(kip1) transfected cells, and (78.37 +/- 2.83)% of p21 (waf1)-p27(kip1) transfected cells. The proportion of cells which contained unnormal centrosomes was obviously decreased, from (13.47 +/- 0.33)% to (5.07 +/- 0.38)%, (6.28 +/- 0.35)%, (3.47 +/- 0.23)%, respectively. The transfer of p21(waf1) and p27(kip1) genes could inhibit the growth of human breast carcinoma cells and the unnormal duplication of centrosomes. p21(waf1) had a really synergy with p27(kip1) in these effects, suggesting p21(waf1)-p27(kip1) combined gene can inhibit the genesis and development of breast cancer and might have potential clinical significance as therapeutic agents of breast cancer.

Andrographolide enhances 5-fluorouracil-induced apoptosis via caspase-8-dependent mitochondrial pathway involving p53 participation in hepatocellular carcinoma (SMMC-7721) cells

Despite recent significant advances in the treatment of human carcinoma (HCC), the results of chemotherapy to date remain unsatisfactory. 5-Fluorouracil (5-FU) still represents the cornerstone of treatment of carcinoma, and resistance to the actions of 5-FU is a major obstacle to successful chemotherapy. More effective treatment strategies may involve combinations of agents with activity against HCC. Andrographolide (ANDRO), a natural bicyclic diterpenoid lactone isolated from Andrographis paniculata, has been shown to suppress the growth of HCC cells and trigger apoptosis in vitro. To assess the suitability of ANDRO as a chemotherapeutic agent in HCC, its cytotoxic effects have been evaluated both as a single agent and in combination with 5-FU. ANDRO potentiates the cytotoxic effect of 5-FU in HCC cell line SMMC-7721 through apoptosis. ANDRO alone induces SMMC-7721 apoptosis with p53 expression, Bax conformation and caspase-3,8,9 activation. Surprisingly, the addition of ANDRO to 5-FU induces synergistic apoptosis, which could be corroborated to the increased caspase-8, p53 activity and the significant changes of Bax conformation in these cells, resulting in increased losses of mitochondrial membrane potential, increased release of cytochrome c, and activation of caspase-9 and caspase-3. Suppression of caspase-8 with the specific inhibitor z-IETD-fmk abrogates largely ANDRO/5-FU biological activity by preventing mitochondrial membrane potential disappearance, caspase-3,9 activation and subsequent apoptosis. The results suggest that ANDRO may be effective in combination with 5-FU for the treatment of HCC cells SMMC-7721.

HIV-Tat protein transduction domain specifically attenuates growth of polyamine deprived tumor cells

Polyamines are essential for tumor cell growth, and the polyamine pathway represents an attractive target for cancer treatment. Several polyamine transport proteins have been cloned and characterized in bacteria and yeast cells; however, the mechanism of polyamine entry into mammalian cells remains poorly defined, although a role for proteoglycans has been suggested. Here, we show that the HIV-Tat transduction peptide, which is known to enter cells via a proteoglycan-dependent pathway, efficiently inhibits polyamine uptake. Polyamine uptake-deficient mutant cells with intact proteoglycan biosynthesis (CHO MGBG) displayed unperturbed HIV-Tat uptake activity compared with wild-type cells, supporting the notion that HIV-Tat peptide interferes with polyamine uptake via competition for proteoglycan binding sites rather than a putative downstream transporter. HIV-Tat specifically inhibited growth of human carcinoma cells made dependent on extracellular polyamines by treatment with the polyamine biosynthesis inhibitor alpha-difluoromethylornithine; accordingly, the Tat peptide prevented intracellular accumulation of exogenous polyamines. Moreover, combined treatment with alpha-difluoromethylornithine and HIV-Tat efficiently blocked tumor growth in an experimental mouse model. We conclude that HIV-Tat transduction domain and polyamines enter cells through a common pathway, which can be used to target polyamine-dependent tumor growth in the treatment of cancer.

AP-2γ Induces p21 Expression, Arrests Cell Cycle, Inhibits the Tumor Growth of Human Carcinoma Cells

Activating enhancer-binding protein 2γ (AP-2γ) is a member of the developmentally regulated AP-2 transcription factor family that regulates the expression of many downstream genes. Whereas the effects of AP-2α overexpression on cell growth are fairly well established, the cellular effects of AP-2γ overexpression are less well studied. Our new findings show that AP-2γ significantly upregulates p21 mRNA and proteins, inhibits cell growth, decreases clonogenic survival. Cell cycle analysis revealed that forced AP-2γ expression induced G1-phase arrest, decreased DNA synthesis, decreased the fraction of cells in S phase. AP-2γ expression also led to cyclin D1 repression, decreased Rb phosphorylation, decreased E2F activity in breast carcinoma cells. AP-2γ binding to the p21 promoter was observed in vivo, the absence of growth inhibition in response to AP-2γ expression in p21 (-/-) cells demonstrated that p21 caused, at least in part, AP-2-induced cell cycle arrest. Finally, the tumor growth of human breast carcinoma cells in vivo was inhibited by the expression of AP-2γ relative to empty vector-infected cells, suggesting that AP-2γ acts as a tumor suppressor. In summary, expression of either AP-2γ or AP-2α inhibited breast carcinoma cell growth; thus, these genes may be therapeutic targets for breast cancer.

Human Carcinoma Cell Growth and Invasiveness Is Impaired by the Propeptide of the Ubiquitous Proprotein Convertase Furin

Furin, a potent proprotein convertase involved in activation of several cancer-related substrates, is synthesized as an inactive zymogen, thus minimizing the occurrence of premature enzymatic activity that would lead to inappropriate protein activation or degradation. This natural inhibitory mechanism is based on the presence of an inactivating prosegment at the NH2 terminal of the zymogen. After initial autocatalytic cleavage, the prosegment remains tightly associated with the convertase until it reaches the trans-Golgi network where the dissociation of the prosegment and activation of furin occurs. We hypothesized that the inhibitory properties of the preprosegment of furin (ppFur) could be beneficial if ectopically expressed in tumor cells. Transfection of four human head and neck squamous cell carcinoma cell lines with the complete ppFur cDNA sequence (pIRES-EGFP-ppFur) or with the empty expression vector (pIRES-EGFP) was done. The inhibitory effect was evaluated using in vivo tumorigenicity, invasion, anchorage-independent growth in soft agar, and proliferation assays, as well as by investigating impairment of furin substrates processing. Following transfection of ppFur, a significant reduction in cell proliferation, tumorigenicity, and invasiveness was observed in vitro and in vivo. These biological changes are directly related to the inhibition of furin-mediated activation of crucial cancer-related substrates, such as membrane type 1 matrix metalloproteinase, transforming growth factor-beta, insulin-like growth factor-1 receptor, and vascular endothelial growth factor-C. PpFur expression in head and neck squamous cell carcinoma cell lines showed a mechanistic link between furin inhibition, decreased substrate processing, cell proliferation, and invasive ability. These findings suggest that furin inhibition is a feasible approach to ameliorate and even abolish the malignant phenotype of various malignancies.

Combination of tumor necrosis factor-alpha with sulindac augments its apoptotic potential and suppresses tumor growth of human carcinoma cells in nude mice.

Resistance to apoptosis may be responsible for a principal mechanism by which cancer cells overcome anticancer therapies. Among antiapoptotic signals, the transcription factor, NF-kappaB, plays a pivotal role in the resistance because it is frequently activated in many primary carcinoma cells. However, NF-kappaB is also activated by several anticancer therapies, including tumor necrosis factor-alpha (TNF-alpha). The NF-kappaB-mediated survival signals are supposed to evade these therapies. Recently, a nonsteroidal antiinflammatory drug, sulindac, and its metabolites have been shown to inhibit the NF-kappaB pathway and to enhance TNF-alpha-mediated apoptosis in lung carcinoma cell lines. In the current study, the authors investigated whether sulindac can augment TNF-alpha-mediated apoptosis in other human carcinoma cells and whether it can be applied for in vivo clinical usage. Human gastric MKN45 and cervical HeLa carcinoma cells were treated with sulindac and/or TNF-alpha. Proapoptotic effects of these agents were evaluated by trypan blue exclusion assay, DNA fragmentation, and caspase-3 activity. The effect of sulindac on NF-kappaB activation was evaluated by luciferase reporter and gel-shift assays. The suppressive effects of these reagents on the subcutaneous tumor growth of MKN45 cells were evaluated by measuring tumor size in nude mice. Sulindac inhibited TNF-alpha-mediated NF-kappaB activation and greatly sensitized MKN45 and HeLa cell lines to TNF-alpha. Moreover, in vivo tumor growth of MKN45 cells was inhibited most strongly by a combination of TNF-alpha with sulindac compared with TNF-alpha or sulindac alone. The current study data strongly suggest that combination therapy of TNF-alpha with sulindac may sensitize tumor cells to TNF-alpha and augment its proapoptotic potential. Therefore, in combination with sulindac, TNF-alpha may become a potentially useful anticancer agent to suppress tumor growth in a wide range of carcinomas.

Neurotensin- and EGF-Induced Metabolic Activation of Colon Carcinoma Cells Is Diminished by Dietary Flavonoid Cyanidin but Not by Its Glycosides

Dietary polyphenols, including anthocyanidins and their glycosides anthocyanins, are suggested to be involved in the protective effects of fruits and vegetables against cancer. Very few data are available concerning the effects of anthocyanidins/anthocyanins on cellular processes induced by growth factors such as neurotensin and epidermal growth factor (EGF), which are implicated in the pathophysiology of colon cancer. Here, we show that neurotensin and EGF caused an increase in the extracellular acidification rate, which could reflect the activity of cellular metabolism, in the human carcinoma cell line HT29 clone 19A. Neurotensin and EGF also caused a strong rise in the intracellular Ca2+concentration, induced phosphorylation of extracellular signal-regulated kinases (ERK1 and ERK2), and stimulated growth of human carcinoma cells. Cyanidin (10 μM), but not its glycosides cyanin and idaein, was able to inhibit the neurotensin- and EGF-induced increased rate of extracellular acidification. In contrast to N-ethyl-N-isopropyl amiloride, an inhibitor of Na+/H+ exchange, cyanidin did not alter the rate of intracellular pH recovery of cells loaded by NH3/NH4+, indicating that cyanidin inhibits cellular metabolism, rather than directly altering Na+/H+ exchange. Cyanidin, but not cyanin and idaein, was able to inhibit an increase in intracellular Ca2+ concentration induced by neurotensin. Neurotensin- and EGF-induced phosphorylation of ERKs was not affected by cyanidin, cyanin, and idaein at ?100 μM. Only cyanidin (100 μM), but not cyanin and idaein, was able to inhibit cellular growth induced by EGF. Thus these findings suggest that a dietary polyphenol cyanidin, but not its glycosides, is a potent inhibitor of mitogen-induced metabolic activity, increase in free intracellular Ca2+, and cellular growth of cultured colon carcinoma cells.

Chromophore-Modified Antitumor Anthracenes. 1. Cytotoxic Activity of 9-Acyloxy 1,5-Dichloroanthracene Analogues

As part of our program aimed at exploring the effect of introducing side chains to the anthracenone chromophore, we synthesized a novel series of 9-acyloxy 1,5-dichloroanthracene derivatives. Reduction of 1,5-dichloro anthraquinone with stannous chloride in boiling HCI and acetic acid with concomitant selective acylation led to the corresponding 9-acyloxy 1,5-dichloroanthracenes. These com pounds were evaluated in vitro for their ability to inhibit the growth of human oral epidermoid carcinoma (KB) cells, human cervical carcinoma (GBM8401) cells and Chinese hamster ovary (CHO) cells, respectively. Compounds 3g, 3j and 3k were more potent against GBM cells than doxorubicin. Compounds 3j and 3v were more potent against KB cells than doxorubicin. Although compound 3j was active against both GBM and KB cells which was not cytotoxic to CHO cells. The implications of 9-acyloxy-l,5-dichloroanthracene analogs as potential anticancer agents are discussed.

Cytolytic and tumor inhibitory antibodies against UK114 protein in the sera of cancer patients

UK114 is a 14 kDa protein identified in the perchloric acid soluble extract of goat liver. Anti-UK114 antibodies identify this protein as expressed by the membrane of human cancer cells. In the present study, anti-UK114 antibodies were detected in the sera of cancer patients by ELISA and by immunofluorescence tests using human cancer cell lines as a target. UK114 protein is antigenic in cancer patients. Human anti-UK114 antibodies have cytolytic effects in vitro and their presence correlates with inhibition of growth of human carcinoma cells xenografted in nu/nu mice. This finding may open new prospects for immunotherapy.

Anti-proliferative effect of the kinase inhibitor K252a on human prostatic carcinoma cell lines.

Members of the K252 family of kinase inhibitors have been demonstrated to inhibit a number of neurotrophin-mediated cellular responses, and to preferentially inhibit the activity of neurotrophin receptors. In this study, we examined the effects of K252a and K252b on the growth of human prostate carcinoma cells, whose growth is, in part, mediated by a prostatic nerve growth factor(NGF)-like protein(s). K252a inhibited [3H]thymidine incorporation by three androgen-independent prostate tumor cell lines (TSU-pr1, DU-145, and PC-3), under basal growth conditions, and in response to growth stimulation by human prostatic stromal (hPS) cell proteins and serum. K252b, which does not readily penetrate cell membranes, had no significant effect on [3H]thymidine incorporation by the prostate tumor cell lines. The decrease in [3H]thymidine incorporation by the cell lines in response to K252a did not appear to be the result of K252a cytotoxicity at concentrations as high as 100 nM, as measured by the Trypan blue assay for cell viability. Treatment of cells for 25 hours with 100 nM K252a resulted in accumulation of TSU-pr1, DU-145, and PC-3 cells in G0/G1, concurrent with a substantial decrease in cells synthesizing DNA. Treatment of androgen-responsive LNCaP prostatic carcinoma cells for 25 hours with 100 nM K252a also resulted in a significant decrease in DNA synthesis. Human recombinant NGF-mediated phosphorylation of a 140-kDa Trk NGF receptor in the TSU-pr1 cell line was inhibited by treatment with 100 nM K252a. Hence, K252a inhibition of Trk phosphorylation most probably contributed, in part, to the inhibition of prostate tumor cell growth in vitro. These results suggest that the mechanism of K252a action may be useful in the design of potential therapies for prostate cancer treatment.