Predicting ligand-dependent tumors from multi-dimensional signaling features

Administration of local anesthetics, such as lidocaine, in the perioperative period improves outcomes of cancer patients. However, its precise mechanism is still unresolved. The growth of human cancer cell lines, including HeLa cells, are suppressed by lidocaine treatment. We identified that growth differentiation factor-15 (GDF-15) was commonly upregulated in lidocaine-treated cancer cell lines. GDF-15 is a divergent member of the transforming growth factor-β (TGF-β) superfamily and it is produced as an unprocessed pro-protein form and then cleaved to generate a mature form. In lidocaine-treated HeLa cells, increased production of GDF-15 in the endoplasmic reticulum (ER) was observed and unprocessed pro-protein form of GDF-15 was secreted extracellularly. Further, lidocaine induced apoptosis and apoptosis-inducible Tribbles homologue 3 (TRIB3) was also commonly upregulated in lidocaine-treated cancer cell lines. In addition, transcription factor C/EBP homologous protein (CHOP), which is a positive regulator of not only GDF-15 but TRIB3 was also induced by lidocaine. Lidocaine-induced growth suppression and apoptosis was suppressed by knockdown of GDF-15 or TRIB3 expression by small interference RNA (siRNA). These observations suggest that lidocaine suppresses the growth of cancer cells through increasing GDF-15 and TRIB3 expression, suggesting its potential application as cancer therapy.

Adenoviral vectors with E1A regulated by tumor-specific promoters are selectively cytolytic for breast cancer and melanoma.

Derlin-1 Is Overexpressed in Non-Small Cell Lung Cancer and Promotes Cancer Cell Invasion via EGFR-ERK–Mediated Up-Regulation of MMP-2 and MMP-9

Non-neoplastic tissues adjacent to tumor is known to influence the progression of the disease. We and others found that there are two types of microenvironment, one of these highly expresses genes associated with epithelial-to-mesenchymal transition (EMT). Tumor adjacent microenvironment (TAME) with wound responses have been observed in >90% of tumor-adjacent tissues, but EMT- characteristics seems to be less common and are observed in less than half of all patients. Our data suggest that the patients with EMT-TAME have worse breast cancer outcome, particularly among estrogen receptor positive patients. Thus, understanding the molecular cross talk between tumor cells and adjacent cells located in the TAME with EMT properties may identify targetable pathways that play a important role in breast cancer progression. Toward this end, we developed an in-vitro model system that can be used to probe paracrine signaling between cancer cells and adjacent cells undergoing EMT. We hypothesized that the presence of EMT signals in the TAME will alter the gene expression and phenotype of epithelial cells. We further hypothesized that the interactions between cancer cells and their TAME would be subtype dependent. Using cell line models of luminal and basal-like breast cancer, we performed cocultures with cancer cells and cell line models of EMT. The latter cell lines were HMLE cells transduced with either Snail or Twist, representing an intermediate state between an epithelial and a fully mesenchymal phenotype. This coculture system allows the study of heterotypic interactions between cancers and TAME cells with EMT characteristics. Gene expression, proliferation, migration, anchorage independent growth and cytokine production of different breast cancer and non-neoplastic cell lines were evaluated. We observed that coculture with models of EMT microenvironments altered the behavior of epithelial cells and that the gene expression changes were relevant to in-vivo in public datasets, showing correlations with both subtype and outcome. Cocultured cells acquired more migratory behavior and reduced expression of cellular adhesion genes, while simultaneously increasing anchorage independent growth and production of cytokines such as IL-6 and IL-8. Furthermore, we observed different response by luminal and basal-like breast cancer cells to the coculture condition, suggesting that the tumor-TAME interactions occur in a tumor subtype dependent fashion. These results reiterate the importance of the surrounding environment on cancer cell phenotypes and document that paracrine interactions with cells undergoing EMT may increase the aggressiveness of some cancers. Identification of specific signaling pathways that define interactions between specific breast cancer subtypes and their microenvironments will lead to new insights regarding tumor biology and identify potential pathway-specific biomarkers and/or targets for prognosis and treatment of breast cancer. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-03-04.

An adenosine analog (IB-MECA) inhibits anchorage-dependent cell growth of various human breast cancer cell lines

Apoptosis is one of the most critical forms of defense against cancer, and the induction of apoptosis by dietary polyphenols represents significant potential for cancer preventive activity. The present study examined polyphenols extracted from selected native Australian fruits—Illawarra plum (Podocarpus elatus Endl., Podocarpaceae), Kakadu plum (Terminalia ferdinandiana Exell, Combretaceae), muntries (Kunzea pomifera F. Muell., Myrtaceae), and native currant (Acrotriche depressa R.Br., Epacridaceae)—for antiproliferative activity against a panel of cancer and normal cell lines. Each fruit selectively inhibited the growth of cancer cell lines in a dose-dependent manner. The mechanism of growth inhibition of the human promyelocytic leukaemia cells (HL-60) was determined to be apoptosis by morphological assessment, DNA fragmentation, flow cytometry, and caspase-3 induction. Furthermore, Kakadu plum was found to activate caspase-7, -9, and poly (ADP-ribose) polymerase (PARP), suggesting it acts via the intrinsic apoptosis pathway. The same fruit also caused direct DNA damage in colon adenocarcinoma cells (HT-29) as detected using the cytokinesis-block micronucleus cytome (CBMN Cyt) assay.

Epithelial ovarian cancer (EOC) remains a major gynecological problem, with a poor 5-year-survival rate due to distant metastases. The identification of microRNAs (miRNAs) may provide a novel avenue for diagnostic and treatment regimens for EOC. Several miRNAs have been reported to be involved in the progression of EOC, among which miRNA (miR)-137 has been observed to be downregulated in the ovarian tissues of patients with EOC. However, the functions of miR-137 in EOC cell apoptosis, migration and invasion remain to be elucidated. In the present study, the expression of miR-137 was measured in clinical ovarian cancer specimens and cell lines using reverse transcription-quantitative polymerase chain reaction. The role of miR-137 in the growth and survival of the SKOV3 human ovarian cancer cell line was determined using several in vitro approaches and in nude mouse models. The results demonstrated that the expression of miR-137 was downregulated in the ovarian cancer specimens and cell lines. It was also observed that enforced expression of miR-137 in the EOC cell lines decreased cell proliferation, clonogenicity, migration and invasion, and induced G1 arrest and cell apoptosis in vitro. Notably, the enforced expression of miR-137 suppressed tumor growth in the nude mice models. These findings suggested that miR-137 may act as a tumor suppressor and be used as a potential therapeutic agent for the treatment of EOC.

The search for effective antibodies (Ab) for curable cancer immunotherapy has been a quest of many research groups in order to find an effective target that exists on the cancer cell surface. So far there have been no conclusive answers to shed light on the search. This study therefore aimed to bridge the gap of cancer therapy. Screening against 49 kinds of cell lines belonging to 11 kinds of solids cancers was performed. Isolation and characterization for approximately 4200 monoclonal antibodies (mAb) was also performed thereafter. Of those mAb 488 clones that turned out to bind to 29 tumor-associated antigens (TAA) were subjected to immunohistochemical (IHC) analyses. Selection of target antigens (Ag) and a potential antibody for cancer therapy was conducted prior to clinical examinations. In order to find predictably effective targets for therapeutic Ab against solid cancers, expression of the Ag on the surface of cancer and normal cells was extensively examined by IHC analyses using fresh cancer specimens resected from patients. In this study, the tendencies of all staining patterns and distribution of the Ab are reported. While all of the TAA appeared to be involved in tumorigenesis, their expression was not restricted to some specific tumor types but rather randomly distributed among various cancers. Some kinds of Ab including anti-epidermal growth factor receptor (EGFR) and anti-human epidermal growth factor receptor 2 (HER2) indicated the frequency of expression in normal cells was generally low. We concluded that identification of 488 mAb and the accumulated results of IHC analyses in this study could be the key for further therapeutic Ab against cancers. The targets that showed cancer-specific expression are expected to be better for therapeutic Ab than the other Ab. Moreover, further investigation into the growth of cancer cell lines using full human IgG form of Ab shows available efficacy in specific cases.

Calcium intake inhibits growth of colon cancer in vivo, the mechanisms of which are not fully elucidated. The objective of this study was to determine whether Ca2+ directly affects the growth of colon cancer cells in vitro and to compare the effects of Ca2+ on the growth of several gastroenteropancreatic cancer cells, including mouse colon cancer (MC-26), human colon cancer (LoVo and WIDR), human gastric cancer (AGS and SII), and human pancreatic cancer (PANC-1 and MIA) cells. All tumor cell lines tested grew in medium containing low concentration (approx 0.16 mM) of Ca2+. Higher concentrations of Ca2+ significantly inhibited the growth of all three colon cancer cell lines tested but had no significant effect on proliferation of the stomach and pancreatic cancer cell lines. Growth of AGS cells, in the presence of 0.1 or 0.5 mM EGTA (resulting in the loss of the extracellular Ca2+) was similar to that observed in the absence of EGTA, indicating that AGS cells were relatively insensitive to loss of extracellular Ca2+. In the presence of TMB-8, an inhibitor of intracellular Ca2+ release, the growth of colonic cancer cell lines was inhibited in a dose-dependent manner, indicating that a minimum basal level of intracellular Ca2+ was required for continued proliferation of colon cancer cells. The stomach cancer cell lines (AGS) was once again less sensitive to the effects of TMB-8 than were the colon cancer cells, indicating an inherent difference in Ca2+ requirements and sensitivity to Ca2+ for growth of different gastroenteropancreatic cancer cells in vitro.(ABSTRACT TRUNCATED AT 250 WORDS)

Expression of the MDR-1/P-glycoprotein gene confers drug resistance both in vitro and in vivo. We previously reported that gene rearrangements resulting in a hybrid MDR-1 transcript represent a common mechanism for acquired activation of MDR-1/P-glycoprotein. We have identified hybrid MDR-1 transcripts in nine MDR-1-overexpressing cell lines and two patients with relapsed ALL. We characterize these rearrangements as follows. 1) Non-MDR-1 sequences in the hybrid MDR-1 transcripts are expressed in unselected cell lines, showing that these sequences are constitutively expressed. 2) The rearrangements occur randomly and involve partner genes (sequences) on chromosome 7 and on chromosomes other than 7. Breakpoints have been characterized in six cell lines. In one, the rearrangement occurred within intron 2 of MDR-1; in the other five, the rearrangement occurred 24 to >96 kb 5' of the normal start of transcription of MDR-1. In one cell line, homologous recombination involving an Alu repeat was observed. However, in the remaining five cell lines, nonhomologous recombination was observed. 3) The rearrangements arise during drug selection. The acquired rearrangements are not detected in parental cells. 4) Five of the six active promoters that captured MDR-1 controlled MDR-1 from a distance of 29 to more than 110 kb 5' to MDR-1. Transcription was initiated in an antegrade or retrograde direction. We conclude that drug selection with natural products targeting DNA or microtubules leads to DNA damage, nonhomologous recombination, and acquired drug resistance, wherein MDR-1 expression is driven by a random but constitutively active promoter.

To explore the effect of histone deacetylase inhibitor, trichostatin A (TSA) on the growth of biliary tract cancer cell lines (gallbladder carcinoma cell line and cholangiocarcinoma cell line) in vivo and in vitro, and to investigate the perspective of histone deacetylase inhibitor in its clinical application. The survival rates of gallbladder carcinoma cell line (Mz-ChA-l cell line) and cholangiocarcinoma cell lines (QBC939, KMBC and OZ cell lines) treated with various doses of TSA were detected by methylthiazoy tetrazolium (MTT) assay. A nude mouse model of transplanted gallbladder carcinoma (Mz-ChA-l cell line) was successfully established, and changes in the growth of transplanted tumor after treated with TSA were measured. TSA could inhibit the proliferation of gallbladder carcinoma cell line (Mz-ChA-l cell line) and cholangiocarcinoma cell lines (QBC939, KMBC and OZ cell lines) in a dose-dependent manner. After the nude mouse model of transplanted gallbladder carcinoma (Mz-ChA-l cell line) was successfully established, the growth of cancer was inhibited in the model after treated with TSA. TSA can inhibit the growth of cholangiocarcinoma and gallbladder carcinoma cell lines in vitro and in vivo.

8-methoxypsoralen reduces AKT phosphorylation, induces intrinsic and extrinsic apoptotic pathways, and suppresses cell growth of SK-N-AS neuroblastoma and SW620 metastatic colon cancer cells

Celecoxib induces dose dependent growth inhibition in nasopharyngeal carcinoma cell lines independent of cyclooxygenase-2 expression

Background: Development of novel agents and drug combinations are urgently needed for the treatment of breast cancer especially triple negative breast cancer (TNBC). P276 is a potent cyclin-dependent kinase inhibitor with excellent antiproliferative activity against various human cancer cell lines. Here, we report the activity of P276, as a single agent and in combination with paclitaxel or gemcitabine/carboplatin in TNBC cell lines. Material and Methods: In vitro effect of P276 on breast cancer cell lines was determined by cytotoxicity assay, flow cytometry, western blotting and immunofluorescence studies. The antiangiogenic potential of P276 was evaluated using HIF-1 a and VEGF inhibition assay, wound healing and tube formation. In vivo efficacy was studied using human xenograft models in SCID and nude mice. Results: Human breast cancer cell lines including TNBC, treated with P276 were found to be highly susceptible with IC50 ranging from 0.3 to 1.0 mM. In MCF-7 (Her2-, BRCA+/−) and MDA-MB-231 (ER-, PR-, Her2-). P276 significantly down regulated cell cycle proteins pRbser780, cyclin D1, Cdk4 and antiapoptotic protein Bcl-2 followed by 80-85% apoptosis. P276 treatment also lead to the inhibition of PARP enzyme activity or PARP cleavage depending on the cell type. Interestingly, P276 inhibited the key angiogenic mediators HIF-1 a and VEGF with IC50 of 0.095mM and 0.31mM respectively in reporter gene based assays. These antiangiogenic effects were confirmed by immunofluorescence and migration studies in TNBC cell lines and endothelial tube formation. In breast cancer patient derived tumor cell line MAXF 401 (basal like) xenografts in nude mice, cyclical dosing of P276 showed growth inhibition of 71%. Moreover, combination studies of P276 with paclitaxel or gemcitabine plus carboplatin showed synergistic effect in TNBC cell lines. Discussion: Our studies provide compelling evidence for the clinical development of P276 for the treatment of triple negative breast cancer either as monotherapy or in combination with paclitaxel or gemcitabine/carboplatin. Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-15-05.

In the search for potential cytotoxic substances produced by Nomuraea rileyi, an active compound was isolated from mycosed insects through an activity guided fractionation process. The compound, cytotoxic against the Sf9 insect cell line, was identified to be ergosterol peroxide (5α, 8α-epidioxy-24(R)-methylcholesta-6, 22-dien-3β-ol) using nuclear magnetic resonance techniques, infrared spectrometry, and mass spectroscopy. Anticancer screens demonstrated that ergosterol peroxide at micromolar concentrations inhibited the growth of hormone-dependent breast cancer cell line (T47D), hormone-independent breast cancer cell line (MDA-MB-231), human epidermoid carcinoma in mouth cell line (KB), human cervical carcinoma cell line (HeLa), lung cancer cell line (H69AR) and human cholangiocarcinoma cell line (HuCCA-1). Ergosterol peroxide showed moderate effects against Spodoptera litura larvae; 46.7% mortality via topical application after 7 day post-treatment whereas the insect’s death was not found in per os application. The amounts of ergosterol peroxide produced by N. rileyi cultures under in vitro and in vivo were determined. The physiological levels of ergosterol peroxide detected in mycosed and mummified cadavers were very low (0.011 and 0.386 μg/larva) less then levels that either inhibited insect cell proliferation or caused insecticidal activity.