Gene expression profiling of drug-resistant small cell lung cancer cells by combining microRNA and cDNA expression analysis

Linlang Guo, Yongguang Liu, Yifeng Bai, Yanqin Sun, Faman Xiao, Ying Guo
European Journal of Cancer 2010, 46 (9): 1692-702
MicroRNAs (miRNAs) are now known to play important roles in the regulation of gene expression for developmental timing, cell proliferation and apoptosis. Therefore, it is likely that they also modulate sensitivity and resistance to anti-cancer drugs. To better understand the molecular mechanisms of multidrug resistance in SCLC and identify novel molecular markers, we evaluated the expression of 856 miRNAs and approximately 22,000 genes using miRNA microarray and cDNA microarray in cellular models of SCLC which were widely used as sensitive (NCI-H69) and resistant cell lines (NCI-H69AR) to chemotherapy. We also analysed the correlations between miRNA and mRNA expression patterns. Further studies were tested to determine whether the differentially expressed miRNAs were involved in multidrug resistance in SCLC. Our results showed that 61 miRNAs are presented significantly (>3-fold) including up-regulation of 24 miRNAs and down-regulation of 37 miRNAs. Among these miRNAs, 48 of 61 differentially expressed miRNAs were firstly reported to be closely associated with drug resistance and 37.7% (24/61) of miRNA genes were organised as 10 clusters in total 61 significantly expressed miRNAs. We also found that only 27 of 69 miRNAs were significantly correlated with 604 of 21,522 70 mRNA transcripts by MAS database. The sensitivity to anti-cancer drugs Cisplatin, Etoposide and Doxorubicin greatly increased or reduced following transfection of the drug-resistant H69AR cells with the mimics or antagomirs of miR-134, miR-379 and miR-495, respectively. miR-134 increases the cell survival by inducing G1 arrest in H69AR cells. MRP1/ABCC1 is negatively regulated by miR-134 and down-regulation of MRP1/ABCC1 at the protein level largely correlates with elevated levels of miR-134 in H69AR cells. Our results support for the first time a substantial role for miRNAs in multidrug resistance in SCLC. miR-134 could be a causal factor of the down-regulation of MRP1/ABCC1 in H69AR cells. These findings provide valuable information for potential utility of these miRNAs as specific diagnostic biomarkers and novel therapeutic approaches for drug resistance of SCLC.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Trending Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"