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Eugenio Erba

Publications and source records attributed to Eugenio Erba.

13 recordsLinked to original sources
PubMed2006

Resveratrol impairs the formation of MDA-MB-231 multicellular tumor spheroids concomitant with ceramide accumulation.

Resveratrol exerts a drastic growth inhibitory effect on human breast cancer MDA-MB-231 cells grown both in vitro and in vivo. Here we show that resveratrol affects the aggregation properties of MDA-MB-231 cells into multicellular tumor spheroids (MCTSs), in association with induction of de novo synthesis of ceramide. After 9 days of 3D growth in the presence of resveratrol (64 microM), MDA-MB-231 cells formed significantly smaller MCTSs. Further, cells from these aggregates failed to form colonies. Addition of resveratrol (64 microM) to preformed MDA-MB-231 MCTSs caused no significant size change, consistent with lack of ceramide induction. Only some apoptotic blebs were found on the MCTSs surface. Altogether these findings indicate that resveratrol might be effective for prevention of breast cancer cell growth.

Breast Neoplasms↗
PubMed2005

Induction of resistance to Aplidin in a human ovarian cancer cell line related to MDR expression.

Aplidin-resistant IGROV-1/APL cells were derived from the human ovarian cancer IGROV-1 cell line by exposing the cells to increasing concentration of Aplidin for eight months, starting from a concentration of 10 nM to a final concentration of 4 microM. IGROV-1/APL cell line possesses five fold relative resistance to Aplidin. IGROV-1/APL resistant cell line shows the typical MDR phenotype: (1) increased expression of membrane-associated P-glycoprotein, (2) cross-resistance to drugs like etoposide, doxorubicin, vinblastine, vincristine, taxol, colchicin and the novel anticancer drug Yondelis (ET-743). The Pgp inhibitor cyclosporin-A restored the sensitivity of IGROV-1/APL cells to Aplidin by increasing the drug intracellular concentration. The resistance to Aplidin was not due to the other proteins, such as LPR-1 and MRP-1, being expressed at the same level in resistant and parental cell line. The finding that cells over-expressing Pgp are resistant to Aplidin was confirmed in CEM/VLB 100 cells, that was found to be 5-fold resistant to Aplidin compared to the CEM parental cell line.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2005

Variolin B and its derivate deoxy-variolin B: new marine natural compounds with cyclin-dependent kinase inhibitor activity.

Variolin B (VAR-B) is a natural product isolated from the sponge Kirkpatrickia variolosa, found in Antarctica. VAR-B has been shown previously to possess potent pro-apoptotic activity. This study was undertaken to investigate the mechanism of action of chemically synthesised VAR-B and its analogue deoxy-variolin B (dVAR-B). In different human cancer cell lines both compounds inhibited colony formation, caused cell cycle perturbations and induced apoptosis at concentrations ranging from 0.1 to 2 microM. LoVo/Dx cells over-expressing Pgp were equally sensitive as the parental cell line to VAR-B and dVAR-B, indicating that variolins are not substrates of Pgp. Although variolins induced an increase in the levels of p53 with an increase in p21, their cytotoxicities did not appear to be dependent on p53 status as their potency was comparable in cells with wild-type p53, or in sub-lines with inactivated p53. Both VAR-B and dVAR-B prevent the cells from entering S phase, blocking cells in G1 and cause an accumulation of cells in G2. The apoptosis induced by VAR-B and dVAR-B occurs very rapidly in some cell lines (e.g., Jurkat leukaemia cells) and is already evident 4h after the beginning of treatment. Although intercalation of dVAR-B in DNA has been demonstrated, neither VAR-B nor dVAR-B produce detectable breaks in DNA. These results are consistent with the in vitro biochemical assays that also demonstrated that dVAR-B is not topoisomerase I or II poison. Instead, each of these variolins appears to inhibit cyclin-dependent kinases (CDKs) in the muM range. CDK1-cyclin B, CDK2-cyclin A and CDK2/cylin E complexes were inhibited in a range of concentrations lower than those required to inhibit the activity of CDK4/cyclin D or CDK7/cyclin H complexes. In conclusion, these variolins are a new class of CDK inhibitors that activate apoptosis in a p53-independent fashion and thus they may be effective against tumours with p53 mutations or deletions.

Adenocarcinoma↗
PubMed2005

Selective effects of the anticancer drug Yondelis (ET-743) on cell-cycle promoters.

Yondelis is a potent DNA-binding anticancer drug isolated from the tunicate Ecteinascidia turbinata currently undergoing phase III clinical trials. We and others have shown selective inhibition to the transcriptional induction of several genes. We tested the hypothesis that Yondelis specifically targets cell-cycle genes. Our analysis on endogenous and transfected reporter systems revealed complex patterns of transcriptional inhibition and, surprisingly, activation. Other inducible systems-the metallothionein and the CYP3A4 promoters-were little affected. We assayed whether interference of DNA binding of the common nuclear factor Y (NF-Y) activator was responsible for the observed inhibition: in vivo chromatin immunoprecipitation analysis in NIH3T3 and HCT116 cells indicates that NF-Y binding is little affected by Yondelis addition. Finally, histone acetylation was modestly affected only on Cdc2 and cyclin B2 but not on other repressed promoters. These data prove that Yondelis is not a general inhibitor of inducible genes, and its selective effects are exerted downstream from transcription factors binding and histone acetyl transferases recruitment.

Animals↗
PubMed2005

Anti-inflammatory properties of the novel antitumor agent yondelis (trabectedin): inhibition of macrophage differentiation and cytokine production.

Yondelis (Trabectedin) is a novel antitumor agent of marine origin extracted from the tunicate Ecteinascidia turbinata. This original compound is active against several human tumors including sarcoma and ovarian and breast adenocarcinoma, as evidenced in phase II clinical trials in advanced multitreated patients. Yondelis is a DNA minor groove binder that blocks cell cycle and interferes with inducible gene transcription in a selective manner. In this study, we investigated the immunomodulatory properties of Yondelis on leukocytes. Human blood monocytes were highly susceptible in vitro to its cytotoxic effect and underwent apoptosis at pharmacologically relevant concentrations (5 nmol/L), whereas lymphocytes were up to 5-fold less sensitive. Macrophages differentiated in vitro with macrophage colony-stimulating factor and tumor-associated macrophages (TAM), isolated from patients with ovarian cancer, were also susceptible. At subcytotoxic concentrations, Yondelis inhibited the in vitro differentiation of monocytes to macrophages. In tumor-treated patients, drug infusion caused a selective decrease of monocyte counts and of ex vivo macrophage differentiation. The in vitro production of two proinflammatory mediators, CCL2 and IL-6, was markedly reduced by Yondelis in monocytes, macrophages, TAM, and freshly isolated ovarian tumor cells. The chemokine CCL2 is the major determinant of monocyte recruitment at tumor sites, whereas IL-6 is a growth factor for ovarian tumors. In view of the protumor activity of TAM and of the strong association between chronic inflammation and cancer progression, the inhibitory effect of Yondelis on macrophage viability, differentiation, and cytokine production is likely to contribute to the antitumor activity of this agent in inflammation-associated human tumors.

Antineoplastic Agents, Alkylating↗
PubMed2004

Chk1, but not Chk2, is involved in the cellular response to DNA damaging agents: differential activity in cells expressing or not p53.

Mammalian Chk1 and Chk2 protein kinases are two important components of the G(2) DNA damage checkpoint. They are activated by upstream kinases (ataxia telangectasia mutated gene and ATM and Rad 3 related gene) and interfere with the activity of the cdc2/cyclinB1 complex, necessary for the G(2)-M transition, through the inactivation of the cdc25 phosphatases (cdc25A and cdc25C). To understand the role of Chk1 and Chk2 in the cellular response to different anticancer agents, we knocked down the expression of each protein or simultaneously of both proteins by using the small interfering RNA technique in the HCT-116 colon carcinoma cell line and in its isogenic systems in which p53 and p21 have been inactivated by targeted homologous recombination. We here show that inhibition of Chk1 but not of Chk2 in p21(-/-) and p53(-/-) cells caused a greater abrogation of G(2) block induced by ionizing radiation and cis-diamine-dichloroplatinum treatments and a greater sensitization to the same treatments than in the parental cell line with p53 and p21 wild type proteins. These data further emphasise the role of Chk1 as a molecular target to inhibit in tumors with a defect in the G(1) checkpoint with the aim of increasing the selectivity and specificity of anticancer drug treatments.

Antineoplastic Agents↗
PubMed2004

Gene expression correlating with response to paclitaxel in ovarian carcinoma xenografts.

We have investigated gene expression profiles of human ovarian carcinomas in vivo during Taxol(R) (paclitaxel) treatment and observed a difference in expression. Nude mice bearing 1A9 or 1A9PTX22 xenografts were given 60 mg/kg of paclitaxel. Therapeutic efficacy was achieved for 1A9, while 1A9PTX22 did not respond. Tumor tissues harvested 4 and 24 h after treatment were evaluated by cDNA microarray against untreated tumors. Paclitaxel caused the modulation of more genes in 1A9 than in 1A9PTX22 tumors, in accordance to their therapeutic response. Most gene expression alterations were detected 24 h after paclitaxel administration and affected genes involved in various biological functions including cell cycle regulation and cell proliferation (CDC2, CDKN1A, PLAB, and TOP2A), apoptosis (BNIP3 and PIG8), signal transduction and transcriptional regulation (ARF1, ATF2, FOS, GNA11, HDAC3, MADH2, SLUG, and SPRY4), fatty acid biosynthesis and sterol metabolism (FDPS, IDI1, LIPA, and SC5D), and IFN-mediated signaling (G1P3, IFI16, IFI27, IFITM1, and ISG15). The modulation of two representative genes, CDKN1A and TOP2A, was validated by Northern analyses on a panel of seven ovarian carcinoma xenograft models undergoing treatment with paclitaxel. We found that the changes in expression level of these genes was strictly associated with the responsiveness to paclitaxel. Our study shows the feasibility of obtaining gene expression profiles of xenografted tumor models as a result of drug exposure. This in turn might provide insights related to the drugs' action in vivo that will anticipate the response to treatment manifested by tumors and could be the basis for novel approaches to molecular pharmacodynamics.

Animals↗
PubMed2003

Differential response of human acute myeloid leukemia cells to gemtuzumab ozogamicin in vitro: role of Chk1 and Chk2 phosphorylation and caspase 3.

Gemtuzumab ozogamicin (GO) is a humanized anti-CD33 antibody conjugated to the anticancer agent calicheamicin, approved for the treatment of CD33+-relapsed acute myeloid leukemia. We have investigated the effects of GO on 4 human myeloid leukemia lines of different French-American-British (FAB) types (KG-1, THP-1, HL-60, and NB-4), observing 3 different types of response. Exposure to GO (10-1000 ng/mL) induced G2 arrest (up to 80% of the cells) followed by apoptosis (45% of the cells) in HL-60 and NB-4 cells. By contrast, in THP-1 cells we observed a strong G2 arrest (up to 75% of the cells) with little apoptosis. Finally, the KG-1 line was completely resistant to the same concentrations of GO. These different responses did not correlate with the levels of expression of either CD33 or multiple-drug resistance proteins, although the higher cyclosporin A (CsA)-inhibitable efflux activity of KG-1 cells may play a role in the resistance of this line to the drug. We could show that Chk1 and Chk2 phosphorylation, but not p53 or p21 expression, correlated with G2 arrest, implicating the ataxia-telangiectasia mutated/ataxia-telangiectasia related (ATM/ATR)-Chk1/Chk2 pathway in the cell cycle response to GO. However, apoptosis was associated with caspase 3 activation. Freshly isolated acute myeloid leukemia (AML) cells showed patterns of response to GO in vitro similar to those observed with the cell lines, including phosphorylation of Chk2 and caspase 3 activation. Our results suggest that the different molecular pathways induced by the drug in vitro may reflect, at least in part, the variable response to GO obtained in vivo.

Acute Disease↗
PubMed2003

Inhibition of nuclear factor-kappaB by a nitro-derivative of flurbiprofen: a possible mechanism for antiinflammatory and antiproliferative effect.

Nonsteroidal antiinflammatory drugs (NSAIDs) are widely used in the treatment of chronic inflammatory states. In addition, they show promise for the prevention and therapy of colon cancers and of Alzheimer's disease, although their gastrointestinal toxicity is of concern for these indications. Nitric oxide-releasing NSAIDs are reported to be safer than their parent compounds. We report here that flurbiprofen nitroxybutyl ester inhibits nuclear factor-kappaB (NF-kappaB) activity and cell growth in L929 cells at a concentration of 100 microM, whereas flurbiprofen is inactive. Inhibition of cell growth is not due to the induction of apoptosis, but to a retardation of all phases of the cell cycle. NF-kappaB is implicated both in the control of immune and inflammatory response and in the control of cell proliferation and apoptosis. Therefore, its inhibition at low concentrations by an NSAID with low gastrointestinal toxicity could be important for all the above-mentioned therapeutic indications.

Animals↗
PubMed2002

A human immunodeficiency virus type 1 pol gene-derived sequence (cPPT/CTS) increases the efficiency of transduction of human nondividing monocytes and T lymphocytes by lentiviral vectors.

We have investigated the capacity of two human immunodeficiency virus type 1-derived lentivectors, differing in the presence of a 118-bp pol fragment containing the cPPT/CTS element, to transduce human normal primary cells of different hematopoietic lineages. Infection of resting monocytes with a high multiplicity of infection (MOI > 10) revealed that the lentivirus carrying the pol fragment (cPPT) is effective, transducing 75% of cells compared with 36% for the no-cPPT vector. Even at low MOIs (< or =1) the cPPT vector still shows a better transduction efficiency than the no-cPPT vector. Moreover, transduction does not require dendritic cell differentiation. In contrast, infection of nonactivated T lymphocytes showed that both vectors, tested at high MOIs, can transduce a small, although measurable, percentage of cells (up to 10%), which may correspond to G(1a) "activated" cells as detected by simultaneous staining of DNA and RNA, in our cultures in the presence of medium alone. Furthermore, we show that the sole addition of interleukin 2 or interleukin 15 represents a full proliferative signal under our conditions and permits high transduction efficiency (up to 30% with the cPPT vector and 15% with the no-cPPT vector). Still higher transduction of T lymphocytes can be achieved after stimulation with phytohemagglutinin and interleukin 2 (up to 78% with the cPPT vector vs. 42% with the no-cPPT vector). Finally, both viruses do not transduce either resting or proliferating tonsillar B lymphocytes.

B-Lymphocytes↗
PubMed2002

The expression of the non-receptor tyrosine kinases Arg and c-abl is differently modulated in B lymphoid cells at different stages of differentiation.

The products of the human ARG gene and the human ABL gene characterize the Abelson family of non-receptor tyrosine protein kinases. Both genes are ubiquitously expressed. The interactions of these two similar protein kinases are still not well known, although it has been suggested that they could cooperate, with redundant actions, to provide intracellular signals in the cells. Lymphopenia occurs in mice with homozygous disruption of c-abl, indicating that in certain tissues Arg is unable to substitute c-abl functions. In B and T lymphoid cell lines at different stages of differentiation, we studied, by a reverse transcriptase-competitive polymerase chain reaction and Western blotting, Arg and c-abl in order to evaluate whether the expression pattern of the two genes could give insight as to why they do not exhibit overlapping roles in lymphocytes and whether the product levels of the two genes are related to lymphoid differentiation. The data showed that their expression is differently modified in lymphoid B cell lines. The highest Arg transcript and protein levels are in the mature B cells.

Actins↗
PubMed2002

Unique features of the mode of action of ET-743.

This paper describes the current knowledge of the primary mode of action of a natural product, ecteinascidin 743 (ET-743), derived from the marine tunicate Ecteinascidia turbinata. ET-743 was initially selected for preclinical development because of its potent antitumor activity observed against several human solid tumor types. In vitro, the drug is cytotoxic in the nanomolar range, and in the case of some very sensitive cell lines, in the picomolar range. The large potency differences observed among several solid tumor types indicate that this compound possesses some tumor selectivity, but the molecular basis of these differential effects remains to be elucidated. The present studies were undertaken to evaluate the mechanism of action of ET-743 in this context. The available information on ET-743 binding to DNA and its effects on transcriptional regulation point to a unique behavior of this drug, as it independently affects specific gene transcription in a promoter-dependent way. In addition, ET-743 shows a peculiar pattern of selectivity in cells with different defects in their DNA-repair pathways. These results highlight a unique property of ET-743, possibly explaining why it possesses antitumor activity against tumors that are refractory to standard anticancer drugs, all of which certainly act by mechanisms that are different from that of ET-743.

Antineoplastic Agents, Alkylating↗