To study in detail the relation between gene expression and resistance against gemcitabine, a cell line was isolated from a tumor for which gemcitabine resistance was induced in vivo. Similar to the in vivo tumor, resistance in this cell line, C 26-G, was not related to deficiency of deoxycytidine kinase (dCK). Micro-array analysis showed increased expression of ribonucleotide reductase (RR) subunits M1 and M2 as confirmed by real time PCR analysis (28- and 2.7-fold, respectively). In cell culture, moderate cross-resistance (about 2-fold) was observed to 1-ss-D-arabinofuranosylcytosine (ara-C), 2-chloro-2'deoxyadenosine (CdA), LY231514 (ALIMTA), and cisplatin (CDDP), and pronounced cross-resistance (>23-fold) to 2',2'-difluorodeoxyuridine (dFdU) and 2',2'-difluorodeoxyguanosine (dFdG). Culture in the absence of gemcitabine reduced resistance as well as RRM1 RNA expression, demonstrating a direct relationship of RRM1 RNA expression with acquired resistance to gemcitabine.

Download full-text PDF

Source
http://dx.doi.org/10.1080/15257770600890269DOI Listing

Publication Analysis

Top Keywords

resistance gemcitabine
12
micro-array analysis
8
increased expression
8
expression ribonucleotide
8
ribonucleotide reductase
8
reductase subunits
8
rrm1 rna
8
rna expression
8
resistance
6
gemcitabine
5

Similar Publications

TP53 mutations are recognized to correlate with a worse prognosis in individuals with non-small cell lung cancer (NSCLC). There exists an immediate necessity to pinpoint selective treatment for patients carrying TP53 mutations. Potential drugs were identified by comparing drug sensitivity differences, represented by the half-maximal inhibitory concentration (IC50), between TP53 mutant and wild-type NSCLC cell lines using database analysis.

View Article and Find Full Text PDF

Background: Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal diseases. Although several chemotherapy regimens have been developed over the past decades, few targeted therapies have shown a significant improvement in overall survival, partly due to the identification of PDAC as a single disease.

Methods: Combining metabolomic analysis and immunohistochemistry staining with Oil Red O staining, analysis for the oxygen consumption rate and extracellular acidification rate, we stratified pancreatic cancer cells into two subtypes.

View Article and Find Full Text PDF

Pancreatic cancer (PC) is a highly lethal malignancy with rapid progression and poor prognosis. Despite the widespread use of gemcitabine (Gem)-based chemotherapy as the first-line treatment for PC, its efficacy is often compromised by significant drug resistance. 1,2,3,4,6-Pentagaloyl glucose (PGG), a natural polyphenol, has demonstrated potential in sensitizing PC cells to Gem.

View Article and Find Full Text PDF

: Pancreatic ductal adenocarcinoma (PDAC), expecting to be the second leading cause of cancer deaths by 2030, resists immune checkpoint therapies due to its immunosuppressive tumor microenvironment (TME). Leukemia inhibitory factor (LIF) is a key target in PDAC, promoting stemness, epithelial-mesenchymal transition (EMT), and therapy resistance. Phase 1 clinical trials showed anti-LIF therapy is safe but with limited efficacy, suggesting better outcomes when combined with chemotherapy, radiotherapy, or immunotherapy.

View Article and Find Full Text PDF

: Platinum-resistant ovarian cancer (PROC) is a major therapeutic challenge, as it responds poorly to standard platinum-based treatment, has limited treatment options, and offers a generally unfavorable prognosis. Chemotherapeutic agents like pegylated liposomal doxorubicin (PLD), topotecan (TOPO), and gemcitabine (GEM) are used for this setting, but with varying efficacy and toxicity profiles, leading to an increasing need to understand the optimal balance between treatment effectiveness and tolerability for improving patient outcomes. This study evaluates the efficacy and side effects of PLD, TOPO, and GEM, focusing on progression-free survival (PFS), overall survival (OS), and safety profiles.

View Article and Find Full Text PDF

Want 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!