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Drug-related laboratory test interference or drug/laboratory test interactions (DLTI) are a major source of laboratory errors. DLTI is of concern with regard to both the clinical diagnosis and the monitoring of patients. Although there have been numerous reports about specific drugs that interfere with laboratory tests, there has not been a recent review on the topic. We herein provide a review of the known DLTI of US FDA-approved drugs based on a systematic search of DailyMed, a website containing the labels of US FDA-approved drugs. The labels for all human single-ingredient prescription drugs included in the database (1368) were searched using stemmed keywords and were manually reviewed for their relevance to DLTI. A total of 134 labels were positive, which indicated that the drug interferes with at least one clinical laboratory test. Antibacterial agents, psychotropic drugs and contrast media are the classes of drugs most likely to lead to DLTI. Urine was the clinical sample most frequently affected by DLTI. The FDA drug label is a source of information for studies of DLTI, although information is still lacking for most drugs, and additional improvements are needed for many of the existing records. Medical professionals, clinicians and laboratory staff should keep these possible interactions in mind when interpreting the results of laboratory tests, and should ensure that they obtain a complete and accurate record of all drugs being used by patients in order to anticipate potential DLTI. The development of a reporting system to address potential DLTI is warranted. [ABSTRACT FROM AUTHOR]

The purpose of the present study was to determine the in vitro and in vivo anti-cancer activity and pharmacological properties of 3,4-dimethoxy-N-[(2,2-dimethyl-2H-chromen-6-yl)methyl]-N-phenylbenzenesulfonamide, KCN1. In the present study, we investigated the in vitro activity of KCN1 on cell proliferation and cell cycle distribution of pancreatic cancer cells, using the MTT and BrdUrd assays, and flow cytometry. The in vivo anti-cancer effects of KCN1 were evaluated in two distinct xenograft models of pancreatic cancer. We also developed an HPLC method for the quantitation of the compound, and examined its stability in mouse plasma, plasma protein binding, and degradation by mouse S9 microsomal enzymes. Furthermore, we examined the pharmacokinetics of KCN1 following intravenous or intraperitoneal injection in mice. Results showed that, in a dose-dependent manner, KCN1 inhibited cell growth and induced cell cycle arrest in human pancreatic cancer cells in vitro, and showed in vivo anticancer efficacy in mice bearing Panc-1 or Mia Paca-2 tumor xenografts. The HPLC method provided linear detection of KCN1 in all of the matrices in the range from 0.1 to 100 µM, and had a lower limit of detection of 0.085 µM in mouse plasma. KCN1 was very stable in mouse plasma, extensively plasma bound, and metabolized by S9 microsomal enzymes. The pharmacokinetic studies indicated that KCN1 could be detected in all of the tissues examined, most for at least 24 h. In conclusion, our preclinical data indicate that KCN1 is a potential therapeutic agent for pancreatic cancer, providing a basis for its future development. [ABSTRACT FROM AUTHOR]

Abstract: 20(S)-25-methoxyl-dammarane-3β, 12β, 20-triol (25-OCH3-PPD), a newly identified natural product from Panax notoginseng, exhibits activity against a variety of cancer cells. Herein, we report the effects of this compound on human A549, H358, and H838 lung cancer cells, and compare these effects with a control lung epithelial cell line, BEAS-2B. 25-OCH3-PPD decreased survival, inhibited proliferation, and induced apoptosis and G1 cell cycle arrest in the lung cancer cell lines. The P. notoginseng compound also decreased the levels of proteins associated with cell proliferation and cell survival. Moreover, 25-OCH3-PPD inhibited the growth of A549 lung cancer xenograft tumors. 25-OCH3-PPD demonstrated low toxicity to non-cancer cells, and no observable toxicity was seen when the compound was administered to animals. In conclusion, our preclinical data indicate that 25-OCH3-PPD is a potential therapeutic agent in vitro and in vivo, and further preclinical and clinical development of this agent for lung cancer is warranted. [Copyright &y& Elsevier]

Abstract: We recently isolated and characterized two novel ginsenosides, 25-OH-PPD and 25-OCH3-PPD. We investigated whether these ginsenosides could represent safe and effective therapeutic agents for pancreatic cancer. In vitro and in vivo studies demonstrated that both compounds inhibited proliferation, caused cell cycle arrest, and induced apoptosis. They also both inhibited the growth of xenograft tumors without any host toxicity. Preliminary investigations into the mechanisms of action of the compounds suggest that their effects may be partially mediated by their inhibition of the MDM2 oncogene and related pathways. The data presented here support further evaluation of the ginsenosides for pancreatic cancer therapy. [Copyright &y& Elsevier]

The mouse double minute 2 (MDM2)–p53 interaction regulates the activity of p53 and is a potential target for human cancer therapy. Here, we report that RYBP (RING1- and YY1-binding protein), a member of the polycomb group (PcG), interacts with MDM2 and decreases MDM2-mediated p53 ubiquitination, leading to stabilization of p53 and an increase in p53 activity. RYBP induces cell-cycle arrest and is involved in the p53 response to DNA damage. Expression of RYBP is decreased in human cancer tissues compared with adjacent normal tissues. These results show that RYBP is a new regulator of the MDM2–p53 loop and that it has tumour suppressor activity. [ABSTRACT FROM AUTHOR]

Panax ginseng and its extracts have long been used for medical purposes; there is increasing interest in developing ginseng products as cancer preventive or therapeutic agents. The present study was designed to determine biological structure–activity relationships (SAR) for saponins present in Panax ginseng fruits. Eleven saponins were extracted from P. ginseng fruits and purified by use of D101 resin and ordinary and reverse-phase silica gel column chromatography. Their chemical structures were elucidated on the basis of physicochemical constants and NMR spectra. Compounds were then evaluated for SAR with their in vitro cytotoxicity against several human cancer cell lines. The 11 compounds were identified as 20( R)-dammarane-3β,12β,20,25-tetrol (25-OH-PPD, 1); 20( R)-dammarane-3β,6α,12β,20,25-pentol (25-OH-PPT, 2); 20( S)-protopanaxadiol (PPD, 3); daucosterine 4, 20( S)-ginsenoside-Rh2 (Rh2, 5); 20( S)-ginsenoside-Rg3 (Rg3, 6); 20( S)-ginsenoside-Rg2 (Rg2, 7); 20( S)-ginsenoside-Rg1 (Rg1, 8); 20( S)-ginsenoside-Rd (Rd, 9); 20( S)-ginsenoside-Re (Re, 10); and 20( S)-ginsenoside-Rb1 (Rb1, 11). Among the eleven compounds, 1, 3 and 5 were the most effective inhibitors of cell growth and proliferation and inducers of apoptosis and cell cycle arrest. For 1, the IC50 values for most cell lines were in the range of 10–60 μM, at least twofold lower than for any of the other compounds. Compounds 1 and 3 had significant, dose-dependent effects on apoptosis, proliferation, and cell cycle progression. The results suggest that the type of dammarane, the number of sugar moieties, and differences in the substituent groups affect their anti-cancer activity. This information may be useful for evaluating the structure/function relationship of other ginsenosides and their aglycones and for development of novel anticancer agents. [ABSTRACT FROM AUTHOR]

The article discusses a study on the potential value of the overexpression of cyclic adenylic acid (cAMP)-dependent protein kinase (PKA) as a cancer marker for various human cancers. With the analysis of the population distribution of the extracellular activity of cAMP-dependent protein kinase (ECPKA), the proponents noted that its combination with other biomarkers, or with imaging techniques such as computed tomography scans, could further improve its utility.

Although previous studies suggested that the tumorigenicity of mouse double minute 2 (MDM2) was due to its negative regulation of p53, the p53-independent interactions may be equally as important. During recent studies utilizing MDM2 inhibitors, we noted that E2F transcription factor 1 (E2F1) was downregulated upon inhibition of MDM2, regardless of the p53 status of the cancer. The present study investigated the mechanisms responsible for the MDM2-mediated increase in E2F1 expression. MDM2 prolongs the half-life of the E2F1 protein by inhibiting its ubiquitination. MDM2 displaces SCFSKP2, the E2F1 E3 ligase. Direct binding between MDM2 and E2F1 is necessary for the negative effects of MDM2 on E2F1 ubiquitination, and deletion of the MDM2 nuclear localization signal does not result in loss of the ability to increase the E2F1 protein level. The downregulation of E2F1 upon MDM2 inhibition was not due to either pRB or p14Arf. In addition, E2F1 was responsible for at least part of the inhibition of cell proliferation induced by MDM2 knockdown. In conclusion, the present study provides evidence that stabilization of the E2F1 protein is likely another p53-independent component of MDM2-mediated tumorigenesis. More knowledge about the MDM2–E2F1 interaction may be helpful in developing novel anticancer therapies.Oncogene (2005) 24, 7238–7247. doi:10.1038/sj.onc.1208814; published online 19 September 2005 [ABSTRACT FROM AUTHOR]

This is the final part of a four-part serial review on oncogenes and their potential use as targets for cancer therapy. Previous sections discussed various categories of oncogenes (growth factors, tyrosine kinases, intermediate signaling molecules, and transcription factors) and the advances made in various strategies being used to alter their actions. This part describes four oncogenes, MDM2, BCL2, XIAP, and Survivin, that are involved in regulation of the cell cycle and apoptosis. [ABSTRACT FROM AUTHOR]

This is the third paper in a four-part serial review on potential therapeutic targeting of oncogenes. The previous parts described the involvement of oncogenes in different aspects of cancer growth and development, and considered the new technologies responsible for the advancement of oncogene identification, target validation, and drug design. Because of such advances, new specific and more efficient therapeutic agents can be developed for cancer. This part of the review continues the exploration of various oncogenes that we have grouped within seven categories: growth factors, tyrosine kinases, intermediate signaling molecules, transcription factors, cell cycle regulators, DNA damage repair genes, and genes involved in apoptosis. Part one discussed growth factors and tyrosine kinases and part two discussed intermediate signaling molecules. This portion of the review covers transcription factors and the various strategies being used to inhibit their expression or decrease their activities. [ABSTRACT FROM AUTHOR]

This is the second part of a four-part review on potential therapeutic targeting of oncogenes. The previous part introduced the new technologies responsible for the advancement of oncogene identification, target validation, and drug design. Because of such advances, new specific and more efficient therapeutic agents can be developed for cancer. This part of the review continues the exploration of various oncogenes, which we have grouped within seven categories: growth factors, tyrosine kinases, intermediate signaling molecules, transcription factors, cell cycle regulators, DNA damage repair genes, and genes involved in apoptosis. Part I included a discussion of growth factors and tyrosine kinases. This portion of the review covers intermediate signaling molecules and the various strategies used to inhibit their expression or decrease their activities. [ABSTRACT FROM AUTHOR]

In the past 10 years, progress made in cancer biology, genetics, and biotechnology has led to a major transition in cancer drug design and development. There has been a change from an emphasis on non-specific, cytotoxic agents to specific, molecular-based therapeutics. Mechanism-based therapy is designed to act on cellular and molecular targets that are causally involved in the formation, growth, and progression of human cancers. These agents, which may have greater selectivity for cancer versus normal cells, and which may produce better anti-tumor efficacy and lower host toxicity, can be small molecules, natural or engineered peptides, proteins, antibodies, or synthetic nucleic acids (e.g. antisense oligonucleotides, ribozymes, and siRNAs). Novel targets are identified and validated by state-of-the-art approaches, including high-throughput screening, combinatorial chemistry, and gene expression arrays, which increase the speed and efficiency of drug discovery and development. Examples of oncogene-based, molecular therapeutics that show promising clinical activity include trastuzumab (Herceptin®), imatinib (Gleevec®), and gefitinib (Iressa®). However, the full potential of oncogenes as novel targets for cancer therapy has not been realized and many challenges remain, from the validation of novel targets, to the design of specific agents, to the evaluation of these agents in both preclinical and clinical settings. In maximizing the benefits of molecular therapeutics in monotherapy or combination therapy of cancer, it is necessary to have an understanding of the underlying molecular abnormalities and mechanisms involved. This is the first part of a four-part review in which we discuss progress made in the last decade as it relates to the discovery of novel oncogenes and signal transduction pathways, in the context of their potential as targets for cancer therapy. This part delineates the latest discoveries about the potential use of growth factors and protein tyrosine kinases as targets for therapy. Later parts focus on intermediate signaling pathways, transcription factors, and proteins involved in cell cycle, DNA damage, and apoptotic pathways. [ABSTRACT FROM AUTHOR]

We herein provide an overview of the single-ingredient U.S. Food and Drug Administration (FDA)-approved drugs that affect human spermatogenesis, potentially resulting in a negative impact on male fertility. To provide this information, we performed an in-depth search of DailyMed, the official website for FDA-approved drug labels. Not surprisingly, hormone-based agents were found to be the drugs most likely to affect human spermatogenesis. The next category of drugs most likely to have effects on spermatogenesis was the antineoplastic agents. Interestingly, the DailyMed labels indicated that several anti-inflammatory drugs affect spermatogenesis, which is not supported by the peer-reviewed literature. Overall, there were a total of 65 labels for drugs of various classes that showed that they have the potential to affect human sperm production and maturation. We identified several drugs indicated to be spermatotoxic in the drug labels that were not reported in the peer-reviewed literature. However, the details about the effects of these drugs on human spermatogenesis are largely lacking, the mechanisms are often unknown, and the clinical impact of many of the findings is currently unclear. Therefore, additional work is needed at both the basic research level and during clinical trials and post-marketing surveillance to fill the gaps in the current knowledge. The present findings will be of interest to physicians and pharmacists, researchers, and those involved in drug development and health care policy.

The MDM2 oncogene is overexpressed in various human cancers. Its expression correlates with the phenotypes of high-grade, late-stage, and more resistant tumors. The auto-regulatory loop between MDM2 and the tumor suppressor p53 has long been considered the epitome of a rational target for cancer therapy. As such, many novel agents have been generated to interfere with the interaction of the two proteins, which results in the activation of p53. Among these agents are several small molecule inhibitors synthesized based upon the crystal structures of the MDM2-p53 complex. With use of high-throughput screening, several specific and effective agents for inhibition of the protein-protein interaction were discovered. Recent investigations, however, have demonstrated that many proteins regulate the MDM2-p53 interaction, and that MDM2 may have p53-independent oncogenic functions. In order for novel MDM2 inhibitors to be translated to the clinic, it is necessary to obtain a better understanding of the regulation of MDM2 and of the MDM2-p53 interaction. In particular, the implications of various interactions between certain regulator(s) and MDM2/p53 under different circumstances need to be elucidated to determine which pathway(s) represent the best targets for therapy. Targeting both MDM2 itself and regulators of MDM2 and the MDM2-p53 interaction, or use of MDM2 inhibitors in combination with conventional treatments, may improve prospects for tumor eradication.

The high mortality rate and lack of effective therapies make lung cancer an ideal target for novel therapeutic agents. The present study was designed to implement a novel chemical synthesis pathway and to determine the biological activities of synthetic makaluvamine analogs in human lung cancer. Seventeen compounds were synthesized and purified, and their chemical structures were elucidated on the basis of physicochemical constants and NMR spectra. Their in vitro activity was determined in human lung cancer cell lines. Based on initial screens, compound Ic was found to be the most potent, and was therefore used as a model for further studies in lung cancer cells. Ic induced both apoptosis and S-phase cell cycle arrest. Furthermore, it activated p53 and induced cleavage of PARP and caspases 8 and 9. Our preclinical data indicate that the makaluvamine analogs are potential therapeutic agents against lung cancer, providing a basis for further development of Ic (and perhaps other analogs) as a novel anti-cancer agent.

Inflammation is closely linked to cancer, and many anti-cancer agents are also used to treat inflammatory diseases, such as rheumatoid arthritis. Moreover, chronic inflammation increases the risk for various cancers, indicating that eliminating inflammation may represent a valid strategy for cancer prevention and therapy. This article explores the relationship between inflammation and cancer with an emphasis on epidemiological evidence, summarizes the current use of anti-inflammatory agents for cancer prevention and therapy, and describes the mechanisms underlying the anti-cancer effects of anti-inflammatory agents. Since monotherapy is generally insufficient for treating cancer, the combined use of anti-inflammatory agents and conventional cancer therapy is also a focal point in discussion. In addition, we also briefly describe future directions that should be explored for anti-cancer anti-inflammatory agents.

The present study demonstrates the efficacy of utilizing TLR9 (toll-like receptor 9) agonism as a potential therapy for colon cancer. We examined the effects of two types of TLR9 agonists: a traditional CpG oligonucleotide and a novel immunomodulatory oligonucleotide in models of colon cancer, both alone and in combination with conventional cancer therapies. Because the tumor suppressor p53 is involved in many anti-cancer pathways, and is mutated in more than 50% of cancers, we determined whether p53 is necessary for the anti-tumor effects observed following treatment with TLR9 agonists. We also established that colon cancer cells express TLR9, which has not been demonstrated previously. The effects of TLR9 agonism on the growth, proliferation and apoptosis of colon cancer cells in vitro was then examined. We report five major discoveries: i) TLR9 agonism results in significant activity in models of colon cancer, ii) TLR9 agonists increase the anti-tumor effects of radiation and chemotherapy, iii) p53 is not required for the anti-cancer effects of TLR9 agonism, iv) human colon cancer cells express TLR9, and v) TLR9 agonism leads to decreased cell survival and proliferation and induces apoptosis of colon cancer cells in vitro. These results provide a basis for future studies determining the potential of utilizing TLR9 agonists for human colon cancer therapy.