Related Experiment Videos
Multiple drug-resistance in variant of a human non-small cell lung carcinoma cell line, DLKP-A
1National Cell and Tissue Culture Centre/Bioresearch Ireland, Dublin City University, Glasnevin.
Abstract:
A 300-fold adriamycin resistant variant (DLKP-A) of the human lung squamous cell carcinoma line DLKP was established by stepwise selection in increasing concentrations of adriamycin. Different levels of cross-resistance were observed towards VP-16, VM-26, colchicine, vincristine and, somewhat unexpectedly, cis-platin. Resistance was stable for at least 3 months in culture in the absence of drug. P-glycoprotein overexpression was detected by immunofluorescence and Western Blotting, and a direct causal role for P-glycoprotein overexpression in the resistant phenotype was established by transfection with an mdr1 specific antisense oligonucleotide. A modified cryopreservation procedure was necessary for the resistant variant line. The resistant population displays clonal heterogeneity with respect to resistance level. A higher frequency of double minute chromosomes was observed in DLKP-A when compared with the parental cell line.
Insights
A new Adriamycin-resistant lung cancer cell line (DLKP-A) was developed, exhibiting cross-resistance to multiple chemotherapy drugs. P-glycoprotein overexpression was identified as the key driver of this drug resistance.
Area of Science:
- Oncology
- Cancer Cell Biology
- Pharmacology
Background:
- Acquired multidrug resistance (MDR) is a major obstacle in cancer chemotherapy.
- Lung squamous cell carcinoma (LSCC) remains a significant health concern, necessitating research into resistance mechanisms.
Purpose of the Study:
- To establish and characterize an Adriamycin-resistant variant of the human LSCC cell line DLKP.
- To investigate the mechanisms underlying the observed drug resistance, including cross-resistance patterns and molecular alterations.
Main Methods:
- Stepwise selection of DLKP cells with increasing Adriamycin concentrations to generate the resistant DLKP-A variant.
- Assessment of cross-resistance profiles against various chemotherapeutic agents (VP-16, VM-26, colchicine, vincristine, cis-platin).
- Detection of P-glycoprotein (P-gp) overexpression using immunofluorescence and Western Blotting; functional validation via antisense oligonucleotide transfection.
Main Results:
- The DLKP-A variant demonstrated a 300-fold resistance to Adriamycin, with stable resistance in vitro for over 3 months.
- Significant cross-resistance was observed towards VP-16, VM-26, colchicine, vincristine, and cis-platin.
- P-glycoprotein overexpression was confirmed, and its causal role in the resistant phenotype was established using mdr1 antisense oligonucleotides.
- The resistant cell line required a modified cryopreservation protocol and exhibited clonal heterogeneity and increased double minute chromosomes.
Conclusions:
- P-glycoprotein overexpression is a critical factor in the Adriamycin-resistant phenotype of the DLKP-A lung cancer cell line.
- The DLKP-A model provides a valuable tool for studying multidrug resistance mechanisms in lung squamous cell carcinoma.
- Understanding resistance mechanisms, including genetic alterations like double minutes, is crucial for developing strategies to overcome therapeutic failures.