Introduction: Methotrexate as a single agent chemotherapy in most women with low risk gestational trophoblastic neoplasia (GTN) has been associated with high treatment rate. Combination of methotrexate with Vitamin A due to reduced number of chemotherapy regime courses is one of the treatment options for patients with low-risk GTN. Therefore, this study was performed with aim to determine the e...

WR99210 but does not affect the intrinsic activity of proguanil. Proc. Natl. Acad. Sci. U. S. A. 94, 10931–10936 30 Walter, R. etal. (1991) Pyrimethamine-resistantPlasmodiumfalciparum lack cross-resistance to methotrexate and 2,4-diamino-5-(substituted benzyl) pyrimidines. Parasitol. Res. 77, 346–350 31 Cunningham, R.F. et al. (1981) Clinical pharmacokinetics of probenecid. Clin. Pharmacokinet....

P-glycoprotein (Pgp), a transmembrane efflux pump encoded by the MDR1 gene, transports various lipophilic drugs that enter the cell by passive diffusion through the lipid bilayer. Pgp-expressing multidrug-resistant cell lines are not usually cross-resistant to a hydrophilic antifolate methotrexate (MTX). MTX enters cells primarily through a folate carrier, but passive diffusion becomes the prim...

BACKGROUND This study aimed to better understand the mechanisms underlying methotrexate (MTX)-resistance in osteosarcoma. METHODS The raw transcription microarray data GSE16089 collected from three MTX-sensitive osteosarcoma (Saos-2) cell samples and three MTX-resistant osteosarcoma (Saos-2) cell samples were downloaded from Gene Expression Omnibus. After data processing, the differentially e...

Series of strains of Streptococcus faecium ATCC 8043, Lactobacillus casei ATCC 7469, and Pediococcus cerevisiae ATCC 8081 with increasing resistance to the active antifolate antimalarial drugs chlorguanide triazine (CGT), pyrimethamine (PM), and trimethoprim (TMP) were isolated. These mutant strains, stable for at least 3 to 5 years, were examined for cross-resistance and collateral susceptibil...

The multidrug resistance-associated protein 1 (MRP1) and the canalicular multispecific organic anion transporter (cMOAT or MRP2) are ATP-binding cassette transporters that confer resistance to some anticancer drugs and efflux glutathione and glucuronate conjugates from the cell. The MRP subfamily of ABC transporters, however, contains at least four other members of which MRP3 (MOAT-D) bears the...

The tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) has been shown in cell cultures to enhance the frequency of resistance to methotrexate. However, we found that TPA could also partially protect human KB cells over a short time (72 h) from the cytotoxicity of several antitumor agents, including 4'-demethylepipodophyllotoxin 9-(4,6-O-ethylidene)-beta-D-glucopyranoside (VP-16), vincris...

A gemcitabine (GEM)-resistant human pancreatic cancer cell line (PANC-1RG7) was established in vitro by gradually increasing GEM concentrations and cloning cell cultures to develop a cellular model of acquired drug resistance studies. We found that PANC-1RG7 cells exhibited significantly different morphological characteristics from parental cells. PANC-1RG7 cells grew slowly (p<0.05), yet the c...

The multidrug resistance-associated protein 1 (MRP1) and the canalicular multispecific organic anion transporter (cMOAT or MRP2) are ATP-binding cassette transporters that confer resistance to some anticancer drugs and efflux glutathione and glucuronate conjugates from the cell. The MRP subfamily of ABC transporters, however, contains at least four other members of which MRP3 (MOAT-D) bears the...