SEARCH · PubMed Health

Results for “anticancer”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 235 records · Page 13Linked to original sources

PubMed2006

Mutated telomeres sensitize tumor cells to anticancer drugs independently of telomere shortening and mechanisms of telomere maintenance.

Telomerase is a ribonucleoprotein complex that maintains the stability of chromosome ends and regulates replicative potential. Telomerase is upregulated in over 85% of human tumors, but not in adjacent normal tissues and represents a promising target for anticancer therapy. Most telomerase-based therapies rely on the inhibition of telomerase activity and require extensive telomere shortening before inducing any antiproliferative effect. Disturbances of telomere structure rather than length may be more effective in inducing cell death. Telomerase RNA subunits (hTRs) with mutations in the template region reconstitute active holoenzymes that incorporate mutated telomeric sequences. Here, we analysed the feasibility of an anticancer approach based on the combination of telomere destabilization and conventional chemotherapeutic drugs. We show that a mutant template hTR dictates the synthesis of mutated telomeric repeats in telomerase-positive cancer cells, without significantly affecting their viability and proliferative ability. Nevertheless, the mutant hTR increased sensitivity to anticancer drugs in cells with different initial telomere lengths and mechanisms of telomere maintenance and without requiring overall telomere shortening. This report is the first to show that interfering with telomere structure maintenance in a telomerase-dependent manner may be used to increase the susceptibility of tumor cells to anticancer drugs and may lead to the development of a general therapy for the treatment of human cancers.

Antineoplastic Agents↗

PubMed2006

Modeling anticancer drug-DNA interactions via mixed QM/MM molecular dynamics simulations.

The development of anticancer drugs started over four decades ago, with the serendipitous discovery of the antitumor activity of cisplatin and its successful use in the treatment of various cancer types. Despite the efforts made in unraveling the mechanism of the action of cisplatin, as well as in the rational design of new anticancer compounds, in many cases detailed structural and mechanistic information is still lacking. Many of these drugs exert their anticancer activity by covalently binding to DNA inducing a distortion or simply impeding replication, thus triggering a cellular response, which eventually leads to cell death. A detailed understanding of the structural and electronic properties of drug-DNA complexes and their mechanism of binding is the key step in elucidating the principles of their anticancer activity. At the theoretical level, the description of covalent drug-DNA complexes requires the use of state-of-the-art computer simulation techniques such as hybrid quantum/classical molecular dynamics simulations. In this review we provide a general overview on: drugs which covalently bind to DNA duplexes, the basic concepts of quantum mechanics/molecular mechanics (QM/MM), molecular dynamics methods and a list of selected applications of these simulations to the study of drug-DNA adducts. Finally, the potential and the limitations of this approach to the study of such systems are critically evaluated.

Antineoplastic Agents↗

PubMed2000

The antibiotic and anticancer active aurein peptides from the Australian Bell Frogs Litoria aurea and Litoria raniformis the solution structure of aurein 1.2.

Seventeen aurein peptides are present in the secretion from the granular dorsal glands of the Green and Golden Bell Frog Litoria aurea, and 16 from the corresponding secretion of the related Southern Bell Frog L. raniformis. Ten of these peptides are common to both species. Thirteen of the aurein peptides show wide-spectrum antibiotic and anticancer activity. These peptides are named in three groups (aureins 1-3) according to their sequences. Amongst the more active peptides are aurein 1.2 (GLFDIIKKIAESF-NH2), aurein 2.2 (GLFDIVKKVVGALGSL-NH2) and aurein 3.1 (GLFDIVKKIAGHIAGSI-NH2). Both L. aurea and L. raniformis have endoproteases that deactivate the major membrane-active aurein peptides by removing residues from both the N- and C-termini of the peptides. The most abundant degradation products have two residues missing from the N-terminal end of the peptide. The solution structure of the basic peptide, aurein 1.2, has been determined by NMR spectroscopy to be an amphipathic alpha-helix with well-defined hydrophilic and hydrophobic regions. Certain of the aurein peptides (e.g. aureins 1.2 and 3.1) show anticancer activity in the NCI test regime, with LC50 values in the 10-5-10-4 M range. The aurein 1 peptides have only 13 amino-acid residues: these are the smallest antibiotic and anticancer active peptides yet reported from an anuran. The longer aurein 4 and 5 peptides, e.g. aurein 4.1 (GLIQTIKEKLKELAGGLVTGIQS-OH) and aurein 5. 1 (GLLDIVTGLLGNLIVDVLKPKTPAS-OH) show neither antibacterial nor anticancer activity.

Amino Acid Sequence↗

PubMed1999

Clinical pharmacology of anticancer agents in relation to formulations and administration routes.

In the past years, alternative administration routes and pharmaceutical formulations of anticancer agents have been investigated in order to improve conventional chemotherapy treatment. The impact of these adjustments on the pharmacokinetics and pharmacodynamics is discussed. A review of the literature shows many examples of alternative administration forms of anticancer agents with improved pharmacokinetics. Local administration routes have been investigated in order to reduce the systemic toxicity and to enhance the local efficacy of conventional chemotherapy. Oral administration of anticancer agents is preferred by patients for its convenience and its potential for outpatient treatment. In addition, oral administration facilitates a prolonged exposure to the cytotoxic agent. However, poor bioavailability and substantial interpatient variability are noted as limitations for oral chemotherapy. Increased tumour selectivity can also be achieved by the use of specific pharmaceutical formulations, such as liposomes and macromolecular drug conjugates. The composition of these formulations often determine the pharmacokinetic behaviour of the formulated drug. In conclusion, several alternative administration forms of anticancer agents have been designed in the past years, with the potential for improvement of conventional chemotherapy, however, more extensive clinical evaluation of these novel strategies is warranted to prove their real clinical value.

Administration, Oral↗

PubMed2006

New paradigms in anticancer therapy: targeting multiple signaling pathways with kinase inhibitors.

Signal transduction in cancer cells is a sophisticated process that involves receptor tyrosine kinases (RTKs) that eventually trigger multiple cytoplasmic kinases, which are often serine/threonine kinases. A number of tumor models have identified several key cellular signaling pathways that work independently, in parallel, and/or through interconnections to promote cancer development. Three major signaling pathways that have been identified as playing important roles in cancer include the phosphatidyl inositol-3-kinase (PI3K)/AKT, protein kinase C (PKC) family, and mitogen-activated protein kinase (MAPK)/Ras signaling cascades. In clinical trials, highly selective or specific blocking of only one of the kinases involved in these signaling pathways has been associated with limited or sporadic responses. Improved understanding of the complexity of signal transduction processes and their roles in cancer has suggested that simultaneous inhibition of several key kinases at the level of receptors and/or downstream serine/threonine kinases may help to optimize the overall therapeutic benefit associated with molecularly targeted anticancer agents. Using targeted agents to inhibit multiple signaling pathways has emerged as a new paradigm for anticancer treatment based on preclinical and clinical data showing potent anti-tumor activity of single drugs inhibiting multiple molecular targets or combination therapies involving multiple drugs with selective or narrow target specificity. Preclinical and clinical studies point to molecules on vascular endothelial cells and pericytes as being important targets for anticancer therapies, as well as molecules on or within tumor cells themselves. This suggests that optimal therapeutic approaches to cancer may involve targeting multiple molecules found in both the tumor and supportive tissues. In this review, we will use the most recent preclinical and clinical data to describe this emerging paradigm for anticancer therapy involving targeting multiple signaling pathways with tyrosine or serine/threonine kinase inhibitors.

Antineoplastic Agents↗

PubMed2000

Liposomal formulations of anticancer drugs: selectivity and effectiveness.

After a delay of roughly 30 years, liposomes are becoming important as drug-targeting systems especially in anticancer therapy. Two liposomal anthracycline formulations are now available for cancer treatment and more are in preclinical tests or in clinical trials. This review summarizes the possibilities to improve the anticancer activity of certain drugs by entrapment in liposomes. We will briefly examine the problems and limitations of liposomal systems, from a pharmacokinetic as well as from a manufacturing viewpoint. Moreover, the anticancer properties of the two new liposomal anthracycline formulations will be discussed with regard to anticancer activity and side effects and compared with the properties of the respective free drugs. Copyright 2000 Harcourt Publishers Ltd.

Journal Article↗

PubMed2002

Protodioscin (NSC-698 796): its spectrum of cytotoxicity against sixty human cancer cell lines in an anticancer drug screen panel.

Protodioscin (NSC-698 796) is a furostanol saponin isolated from the rhizome of Dioscorea collettii var. hypoglauca (Dioscoreaceae), a Chinese herbal remedy for the treatment of cervical carcinoma, carcinoma of urinary bladder and renal tumor for centuries. To systematically evaluate its potential anticancer activity, protodioscin was tested for cytotoxicity in vitro against 60 human cancer cell lines in the NCI's (National Cancer Institute, USA) anticancer drug screen. As a result, protodioscin was cytotoxic against most cell lines from leukemia and solid tumors in the NCI's human cancer panel, especially selectively against one leukemia line (MOLT-4), one NSCLC line (A549/ATCC), two colon cancer lines (HCT-116 and SW-620), one CNS cancer line (SNB-75), one melanoma line (LOX IMVI), and one renal cancer line (786 - 0) with GI50 < or = 2.0 microM. In the general view of mean graphs, leukemia, colon cancer and prostate cancer are the most sensitive subpanels, while ovarian cancer is the least sensitive subpanel. Based on an analysis of COMPARE computer program with protodioscin as a seed compound, no compounds in the NCI's anticancer drug screen database have cytotoxicity patterns (mean graphs) similar to those of protodioscin, indicating that a potential novel mechanism of anticancer action is involved.

Antineoplastic Agents, Phytogenic↗

PubMed2005

Tumor-specific targeting of an anticancer drug delivery system by LHRH peptide.

The central problem in cancer chemotherapy is the severe toxic side effects of anticancer drugs on healthy tissues. Invariably the side effects impose dose reduction, treatment delay, or discontinuance of therapy. To limit the adverse side effects of cancer chemotherapy on healthy organs, we proposed a drug delivery system (DDS) with specific targeting ligands for cancer cells. The proposed DDS minimizes the uptake of the drug by normal cells and enhances the influx and retention of the drug in cancer cells. This delivery system includes three main components: (i) an apoptosis-inducing agent (anticancer drug), (ii) a targeting moiety-penetration enhancer, and (iii) a carrier. We describe one of the variants of such a system, which utilizes camptothecin as an apoptosis-inducing agent and poly(ethylene glycol) as a carrier. Luteinizing hormone-releasing hormone (LHRH) was used as a targeting moiety (ligand) to LHRH receptors that are overexpressed in the plasma membrane of several types of cancer cells and are not expressed detectably in normal visceral organs. The results showed that the use of LHRH peptide as a targeting moiety in the anticancer DDS substantially enhanced the efficacy of chemotherapy, led to amplified apoptosis induction in the tumor, and minimized the side effects of the anticancer drug on healthy organs. The LHRH receptor targeting DDS did not show in vivo pituitary toxicity and did not significantly influence the time course or the plasma concentration of luteinizing hormone and its physiological effects on the reproductive functions of mice.

Animals↗

PubMed2000

Coping of parents and siblings with the death of a child with cancer: death after terminal care compared with death during active anticancer therapy.

Seventy pediatric patients with cancer treated at the Hospital for Children and Adolescents, University of Helsinki, Finland, died while in terminal care and 30 children of therapy-related complications during active anticancer therapy in the period 1987-92. The purpose of this study was to compare these groups and characterize the main problems of the families during the mourning process. The method of evaluation was a structured interview of every parent separately. Parents of 60/70 children after terminal care, and parents of 26/30 children who died during active anticancer therapy, were interviewed. Unexpectedly, differences were minimal between families who lost a child after terminal care and those whose child died during active anticancer therapy. Parents reported physical and/or mental problems with similar frequency (39% and 34%); average self-reported recovery times were similar (14 and 16 mo); return to work was similar in both groups, 70% returning doing so within 1 mo. However, pronounced differences were observed between the mothers and the fathers; the mothers requiring longer recovery times and returning to work later. Of the siblings, 18% in the terminal care group had problems compared with 32% in the active therapy group. These included fear, behavioral problems, problems with friends and school-related problems. In conclusion, when a child with cancer dies, the ability of the respective families to cope does not seem to differ whether the child dies after terminal care or during active anticancer therapy. The inevitable loss of the child is the major event. Most parents and siblings have the potential and ability to recover normally after the death of a child, although they will never be completely the same.

Adaptation, Psychological↗

PubMed2004

Communication about the ending of anticancer treatment and transition to palliative care.

BACKGROUND: Communication about the ending of anticancer treatment and transition to palliative care is a difficult task for oncologists. The primary aims of this study were to clarify family-reported degree of emotional distress and the necessity for improvement in communication methods when communicating about the ending of anticancer treatment, and to identify factors contributing to the levels of emotional distress and the necessity for improvement. METHODS: A multi-center questionnaire survey was conducted on 630 bereaved family members of cancer patents who received specialized palliative care in Japan. A total of 318 responses were analyzed (effective response rate, 62%). RESULTS: Thirty-nine percent of the bereaved family members reported that they were 'very distressed' in receiving information about the ending of anticancer treatment, and 19% reported 'considerable' or 'much' improvement was necessary in the communication methods. High-level emotional distress was significantly associated with younger patient age, female family gender, the experience of the physician stating she/he could do nothing for the patient, the physician's unwillingness to explore their feelings, and prognostic disclosure of definite survival periods without probabilities or ranges. High levels of perceived necessity for improvement in the communication methods were significantly associated with the experience of the physician stating she/he could do nothing for the patient, physicians not explaining treatment goals in specific terms, physicians not pacing the explanation with the state of family preparation, physicians not being knowledgeable about the most advanced treatments, and the atmosphere not being relaxing enough to ask questions. CONCLUSIONS: In receiving the information about ending anticancer treatment, a considerable number of families experienced high levels of emotional distress and felt a need for improvement of the communication methods. The strategies to alleviate family distress could include: (i) assuring that physicians will do their best to achieve specific goals, without saying that they can do nothing for the patient; (ii) providing information, including estimated prognosis, in careful consideration of families' preparation and the uncertainty for each patient; (iii) exploring families' emotions and providing emotional support; (iv) acquiring knowledge about advanced treatments; and (v) making the atmosphere relaxing enough to allow families to ask questions.

Aged↗

PubMed2003

Standardization of the body surface area (BSA) formula to calculate the dose of anticancer agents in Japan.

BACKGROUND: The importance of deciding the appropriate dose of anticancer agents cannot be overemphasized. Body surface area (BSA) has been used to calculate the dose in anticancer therapy since the 1950s. Japanese oncologists, often use their own Japanese BSA formula instead of western BSA formulae. However, it is not widely known that some discrepancies exist between the BSA products of the Japanese and western styles. On the other hand, recently dose-calculations according to BSA were criticized from the standpoint of pharmacokinetics (PK). Lately, we have had many opportunities for international collaborations, which make it necessary to review these BSA formulae, and the BSA-based dosing method. A unified BSA formula in cancer therapy is needed in Japan. METHODS: We searched and compiled frequently used BSA formulae across the world using the MEDLINE search, oncology text, a web search on cancer clinical trial groups, and personally communicated with medical oncologists from western countries. Using these formulae, we calculated BSA for a typical Japanese individual, and compared their products. We calculated BSA using these formulae for individuals of widely varying physique, from 140 to 185 cm in height, and from 30 to 96 kg in weight, and estimated the amount of discrepancies among them. RESULTS: Among the various BSA formulae used in western countries, the DuBois formula is the standard. In Japan, the Fujimoto formula has been used frequently. The Fujimoto formula was based on a study of 201 Japanese subjects in 1949. For the average Japanese individual, the BSA calculated using the Fujimoto formula was about 3% lower than that which was calculated by western formulae. The BSA calculated for all heights and body weights using the Fujimoto formula, ranged between 0.7 and 4.8% less than those calculated by using the DuBois formula. The other western formulae showed larger discrepancies than the Fujimoto and DuBois formulae. CONCLUSION: BSA-based dosing has failed to standardize the variation in PK for most anticancer agents, and individual dosing techniques are currently being investigated. However, until their clinical utilities are confirmed, it is necessary to depend on the BSA-based calculation for determining the dose of most anticancer agents. The DuBois formula, which is the western standard formula, is validated to a greater extent and its accuracy has been confirmed more than others, including the Fujimoto formula. We recommend the use of the DuBois formula instead of the Fujimoto formula in cancer chemotherapy and propose the standardization of this formula in Japan.

Adult↗

PubMed1989

Development of a rapid chemosensitivity test for anticancer drugs with contact-sensitive monolayers of Balb/3T3 cells.

We investigated whether lethally irradiated, contact-sensitive Balb/3T3 cell confluent monolayers, termed "cell mats," could be used for the screening of human tumors for sensitivity to anticancer drugs. Cell mats greatly inhibited the growth of normal Balb/3T3 cells and normal human fibroblasts but did not inhibit the growth of human tumor cells. To assess chemosensitivity of tumor cells, we measured the [14C]thymidine (dThd) incorporation by tumor cells that had been plated and then treated with various anticancer drugs on the cell mats. Although the [14C]dThd incorporation assay, when compared with the colony-formation assay, underestimated the toxicity of certain drugs, the assays gave similar results with regard to the degree of colony inhibition and to the decrease in [14C]dThd incorporation when various anticancer drugs were used at the same concentration ranges. Therefore, the method we used for measuring the isotope uptake in the cell mats could also be used to test for tumor-specific chemosensitivity. Because our results from this assay on various human tumor cells, including those from primary human tumors, can be obtained within 5 days, we believe that the system is potentially useful for testing anticancer drugs against human tumors in vitro.

Cell Division↗

PubMed1998

Induction of metallothionein isoforms in rat hepatoma cells by various anticancer drugs.

The induction of metallothionein (MT) isoforms (MT-1, -2) by anticancer drugs was investigated in cultured rat hepatoma H4 II E C3 cells. The steady-state expression of MT-1 mRNAs was higher than that of MT-2 mRNAs. During incubation of the cells with various anticancer drugs, namely, adriamycin, epirubicin, cis-diamminedichloroplatinum(II) (CDDP), and cis-diammine(1, 1-cyclobutyldicarboxylato)platinum(II), both MT-1 and MT-2 mRNAs were coordinately inducible: the levels of isoMT mRNA reached a maxim of approximate by 6-fold at 3 h. Immunofluorescent studies revealed that the cytosolic fluorescence in the cells exposed to 1 microM CDDP for 48 h was more intensified than that in the untreated cells. Transfer of antisense oligonucleotides resulted in marked reduction of isoMT mRNA, and upon exposure to 5 microM CDDP for 48 h, the viabilities of these cells dropped to 25.8% of the controls. These results indicate that anticancer drugs are potent inducers of MT isoforms in hepatoma cells and that a decrease in cellular MTs enhances the susceptibility of hepatoma cells to CDDP. Thus, we conclude that endogenous MTs play a role in determining the sensitivity or resistance of cancer cells to clinically important anticancer agents.

Animals↗

PubMed2001

Methyl protogracillin (NSC-698792): the spectrum of cytotoxicity against 60 human cancer cell lines in the National Cancer Institute's anticancer drug screen panel.

Methyl protogracillin (NSC-698792) was a furostanol saponin isolated from the rhizome of Dioscorea collettii var. hypoglauca (Dioscoreaceae), a Chinese herbal remedy for the treatment of cervical carcinoma, carcinoma of urinary bladder and renal tumor for centuries, in our previous studies. In order to systematically evaluate its potential anticancer activity, methyl protogracillin was tested for its cytotoxicity in vitro against 60 human cancer cell lines in the National Cancer Institute (NCI)'s anticancer drug screen. As a result, it was found that methyl protogracillin was cytotoxic against all the tested cell lines from leukemia and solid tumors in the NCI's human cancer panel; it showed particular selectivity against one colon cancer line (KM12), one central nervous system (CNS) cancer line (U251), two melanoma lines (MALME-3M and M14), two renal cancer lines (786-0 and UO-31) and one breast cancer line (MDA-MB-231) with GI50< or =2.0 microM. The selectivity between these seven most sensitive lines and the least sensitive line (CCRF-CEM) ranged from 26- to 56-fold. In the same cancer subpanel, selectivity more than 15-fold was observed between MDA-MB-231 and MCF-7, NCI-ADR-RES, BT-549 in breast cancer. From a general view of the mean graph, CNS cancer is the most sensitive subpanel, while ovarian cancer and renal cancer are the least sensitive subpanels. Based on an analysis of the COMPARE computer program with methyl protogracillin as a seed compound, no compounds in the NCI's anticancer drug screen database have similar cytotoxicity patterns (mean graph) to that of methyl protogracillin, indicating a potential novel mechanism of the anticancer action involved.

Antineoplastic Agents↗

PubMed2001

Subcellular redistribution of BAX during apoptosis induced by anticancer drugs.

BAX is the 192-amino acid, 21-kDa protein which is ubiquitously distributed in normal tissues and is regarded as a tumor suppressor sensitizing malignant cells to anticancer drugs. In spite of many studies, the molecular mechanism of BAX action is still obscure. In the present study subcellular BAX translocations in human colon adenocarcinoma COLO 205 cells exposed to various anticancer drugs [camptothecin (CPT), etoposide (ETO), staurosporine (STP), 2-chloro-2'-deoxyadenosine (2CdA) and nimesulide (NIM)] was examined. Cells were grown on coverslips under optimal conditions (10% FCS/DMEM) or were stimulated to apoptosis with the drugs examined. Laser scanning cytometry was applied for the quantitative analysis of BAX expression, and distribution in the cytoplasmic (BAX Cf) and nuclear (BAX Nf) area. BAX maximal pixel (BAX MP), the parameter corresponding to aggregation of BAX in the cell, was also measured. All examined drugs increased the number of cells with high BAX MP, reaching the peak at 60 min after drug administration. The most pronounced effect was in the case of 2CdA, CPT and STP. The increase in BAX MP was observed only when antibody recognizing the 43-61 amino acid sequence was used. When antibody binding the N-terminal epitope (11-30 amino acid sequence) was applied, the number of cells expressing high BAX MP significantly decreased. These results indicate that apoptotic stimuli delivered by anticancer drugs led to aggregation of BAX in cancer cells, which is dependent on BAX activation by its cleavage at the N-terminal epitope and exposure of the BH3 domain. It was shown that BAX Nf increased in cells treated with CPT, STP, ETO, 2CdA and NIM, whereas BAX Cf rose after STP and NIM. The increase in BAX Nf and, occurring in most treatments, the increase in the BAX Nf:Cf ratio indicates a BAX shift from the cytoplasm to the nucleus. Furthermore, staining with different antibodies showed that only the activated form of BAX was translocated to the nucleus. Immunoelectron microscopy revealed that CPT-induced apoptosis was associated with translocation of BAX from the cytosol to organellar membranes (mitochondrial, Golgi apparatus and endoplasmic reticulum) and via nuclear envelope pores to the nucleus, occurring within 60-180 min of cell exposure to the drug. The subcellular translocations of BAX preceded in time the appearance of morphological symptoms of apoptosis. In conclusion, (i) in spite of different molecular mechanisms of apoptosis induction by the anticancer drugs examined, BAX remains a common link in the chain of reactions leading to cell death, and (ii) BAX activation and subcellular translocations from the cytosol to organellar membranes and nucleus are key cellular responses to drugs bearing proapoptotic properties.

Adenocarcinoma↗

PubMed2002

Down-regulation of telomerase activity by anticancer drugs in human ovarian cancer cells.

Maintenance of telomere length is crucial for survival of cells. Telomerase, an enzyme that is responsible for elongation of shortened telomeres, is active in human germ cells as well as most tumor tissues and experimentally immortalized cells. In contrast, most mature somatic cells in human tissues express undetectable or low telomerase activity, implying the existence of a stringent and negative regulatory mechanism. In this study we report the effects of anticancer drugs on telomerase activity in human cancer cells. In assaying for telomerase activity, we basically followed the original TRAP assay system, but with some modifications. A down-regulation of telomerase activity was found when cells of a human ovarian cancer cell line, A2780, were treated with;cis-diamminedichloroplatinum(II) (CDDP; cisplatin). However, down-regulation of telomerase activity was not found in cells of a cisplatin-resistant cell line, A2780CP, treated with cisplatin. On the other hand, telomerase activity in both the cell lines A2780 and A2780CP was reduced when A2780 or A2780CP was treated with adriamycin, an anthracycline antibiotic having a broad spectrum of antineoplastic activity. The different effects on the telomerase activity of the two types of anticancer drugs may be due the distinct chemical functions of these drugs. The present results may indicate a positive relationship between anticancer effects and down-regulation of telomerase activity by anticancer drugs.

Antibiotics, Antineoplastic↗

PubMed2005

In vitro assays for anticancer drug discovery--a novel approach based on engineered mammalian cell lines.

Despite decisive progress in understanding the molecular biology of cancer development, cytotoxic anticancer drugs continue to be the cornerstone of modern antitumor therapies. The developmental therapeutics program, initiated by the US National Institutes of Health's National Cancer Institute in the early 1990s, pioneered massive-scale screening for agents able to phenotypically interfere with the growth and viability of neoplastic cell lines derived from a representative panel of human carcinogenic tissues. Capitalizing on advanced knowledge of molecular processes particular for neoplastic cell characteristics, target-specific screening scenarios became since increasingly popular. With drug targets defined, natural and synthetic (combinatorial) compound/peptide/nucleic acid libraries available and the high-throughput screening technology of the systems' biology era in place, the quo vadis of anticancer drug discovery seems to be well determined. We review recent advances in cytotoxic anticancer drug assay design with emphasis on a novel mammalian cell-based anticancer drug finder technology for the discovery of cytotoxic drugs with fewer side-effects on non-dividing cells.

Animals↗

PubMed2004

Tumor-stroma interaction of human pancreatic cancer: acquired resistance to anticancer drugs and proliferation regulation is dependent on extracellular matrix proteins.

INTRODUCTION: Pancreatic cancer is one of the major causes of cancer-related deaths in industrialized countries. It is known that pancreatic cancer is resistant to chemotherapy and that cancer cells are surrounded by extracellular matrix (ECM) proteins including collagen I, collagen IV, fibronectin, and laminin. AIMS: To examine the role of ECM proteins in acquired resistance to anticancer drugs and proliferation regulation in pancreatic cancers. METHODOLOGY AND RESULTS: We used an in vitro model of ECM-induced chemoresistance and cell proliferation of cancer cell lines (MIA PaCa-2, PANC-1, and Capan-1) with 3 different malignancy grades and found that resistance to cytotoxic drugs and proliferation regulation was dependent on ECM proteins. Pancreatic cancer cell lines, especially MIA PaCa-2 cells, adhering to any of the ECM proteins showed decreased cytotoxicity of anticancer drugs, except for gemcitabine. PANC-1 and Capan-1 cells adhering to fibronectin, collagen I, and collagen IV proliferated more than the controls. CONCLUSION: ECM proteins have important roles in acquired resistance to anticancer drugs and cell proliferation regulation of pancreatic cancer cells. Therefore, the expression of ECM proteins in pancreatic cancer specimens could provide valuable information to aid anticancer drug cytotoxicity, and gemcitabine would be useful for treatment of patients with pancreatic cancer.

Antineoplastic Agents↗