DNA adduct formation is assumed to be a major carcinogenic event, leading to the development of endometrial cancer in breast cancer patients taking tamoxifen and healthy women enrolled in a tamoxifen chemopreventive trial. To determine whether DNA adducts were formed by tamoxifen, trans- and cis-alpha-acetoxytamoxifen N-oxides were synthesized as model-activated forms via major tamoxifen metabolites, tamoxifen N-oxide and alpha-hydroxytamoxifen N-oxide. When alpha-acetoxytamoxifen N-oxide was reacted with human DNA, at least three DNA adducts were detected by (32)P-postlabeling coupled with HPLC. The total amount of DNA adducts formed by trans-alpha-hydroxytamoxifen N-oxide was 1.5-fold higher than that formed by the cis form. Both trans- and cis-alpha-acetoxytamoxifen N-oxide reacted with 2'-deoxyguanosine, resulting in the formation of three adducts (fr-1, fr-2-1, and fr-2-2). These products were studied using mass spectroscopy and proton magnetic resonance spectroscopy. fr-1 was identified as a mixture of the epimers of trans-alpha-(N(2)-deoxyguanosinyl)tamoxifen N-oxide. fr-2-1 and fr-2-2 were determined to be epimers of cis-alpha-(N(2)-deoxyguanosinyl)tamoxifen N-oxide.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1021/tx990132+ | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Upcycling Poly(vinyl chloride) and Polystyrene Plastics Using Photothermal Conversion.
J Am Chem Soc
January 2025
Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Poly(vinyl chloride) (PVC) and polystyrene (PS) are among the least recycled plastics. In this work, we developed a simple and novel strategy to valorize PVC and PS plastics via photothermal conversion to (1-chloroethyl)benzene, a commodity chemical with excellent versatility. As PVC is known to release HCl gas and decompose into conjugated polyenes, we envisioned a dual role for PVC plastics.
View Article and Find Full Text PDFPlatinum micromotors for mucosal penetration and colorectal cancer therapy.
Int J Pharm
January 2025
Clinical Center for Tumor Therapy, The Second Affiliated Hospital of Chongqing Medical University, Chongqing 400010, China. Electronic address:
The therapeutic outcomes of medications were restricted by the colonic mucosal barrier during the treatment of colorectal cancer (CRC). Micro/nanomotors can overcome the mucus barriers to reach deep colorectal tumors. In this study, we constructed a novel microsized PLGA-Pt micromotor (MM) driven by hydrogen peroxide (HO) to enhance drug delivery to the CRC tissues and achieve effective antitumor therapy.
View Article and Find Full Text PDFPromoted read-through and mutation against pseudouridine-CMC by an evolved reverse transcriptase.
Commun Biol
January 2025
Department of Chemistry, Merkert Chemistry Center, Boston College, Chestnut Hill, MA, USA.
Pseudouridine (Ψ) is an abundant RNA chemical modification that plays critical biological functions. Current Ψ detection methods are limited in identifying Ψs at base-resolution in U-rich sequence contexts, where Ψ occurs frequently. Here we report "Mut-Ψ-seq" that utilizes the classic N-cyclohexyl N'-(2-morpholinoethyl)carbodiimide (CMC) agent and an evolved reverse transcriptase ("RT-1306") for Ψ mapping at base-resolution.
View Article and Find Full Text PDFMethionine thioether reduces the content of 4-hydroxy-2-nonenal in high-temperature soybean oil by preventing the radical chain reaction.
Food Chem
January 2025
National Key Laboratory, School of Food Science and Technology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, China.
This study investigated how methionine (Met) reduced 4-hydroxy-2-nonenal (4-HNE) generation during the heating of soybean oil. The results showed that Met at 5 mM, 10 mM, 15 mM, 20 mM and 30 mM reduced the 4-HNE content by 0.67 %, 58.
View Article and Find Full Text PDFMicrocapsule-Containing Self-Reporting Materials Based on Donor-acceptor Stenhouse Adducts.
ACS Macro Lett
January 2025
Department of Chemical Engineering, Key Laboratory of Advanced Materials (MOE), Tsinghua University, Beijing 100084, China.
The microcapsule-containing self-reporting system has attracted attention for its excellent characteristics in visualizing microdamage. In this study, we developed self-reporting materials based on the formation of donor-acceptor Stenhouse adducts (DASA) from microcapsules containing Meldrum's acid furfural conjugate (MAFC). Under mechanical force, MAFC is released from broken microcapsules and forms highly colored DASA with secondary amines in the matrix to indicate the small cracks or deformations.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!