In addition, detection of ABCG2 expression may assist in predicting the chemotherapeutic outcome of patients, and serve as a target for treating lung cancer.
Here, we demonstrate upregulation of multidrug transporters ABCB1 and ABCG2 as a major mode of resistance to THZ1, a covalent inhibitor of CDKs 7, 12, and 13 in neuroblastoma and lung cancer.
Interestingly, 10 or 20 μM of cariprazine significantly decreased the expression levels of the ABCG2 protein in the colon and lung cancer cell lines, suggesting that cariprazine inhibits both the function and expression of ABCG2 transporters at nontoxic concentrations.
In the present study, we acidized the medium with 2-(N-morpholino)-ethanesulfonic acid (MES monohydrate) to mimic the acidic tumor microenvironment and observed the effects of acidification on lung cancer cell viability, the expression of ATP-binding cassette sub-family G member 2 (ABCG2) and myeloid cell leukemia‑1 (Mcl-1), and activation of the PI3K-Akt pathway.
We further found that the PI3K/Akt inhibitor LY294002 down-regulated BCRP expression, hence showing that the Akt pathway is involved in the regulation of BCRP expression but not in its localization in these lung cancer cell lines.
Lung cancer cell line NCI-H460 and its ABCG2-overexpressing NCI-H460/MX20, as well as the ABCG2-, ABCB1-, and ABCC10-overexpressing transfected cell lines were used for the reversal study.
Moreover, camptothecin and cisplatin-induced ABCG2 and MRP2 upregulation could be impaired by ATM and NF-κB inhibitors, indicating a relationship between ATM, NF-κB activation and MDR formation in lung cancer chemo-therapy.
Therefore, it might be that ABCG2, abundantly expressed in the stem cell population of A549 cells, can modulate resistance to MTX in lung cancer therapy.
This study characterized genetic variability of the ABCB1 (also known as MDR1), ABCC2 (MRP2) and ABCG2 (BCRP) genes, which are key players in the metabolism of many chemotherapeutic agents including those used in the treatment of lung cancer.
Germline polymorphisms can be easily assessed in blood samples, and polymorphisms in EGFR, AKT1 and ABCG2 have been correlated with outcome and toxicity in lung cancer patients given EGFR-TKIs therapies.
After cytological confirmation of lung cancer type, total RNA was extracted from biopsy samples and reverse transcribed to cDNA, and real-time PCR for the genes of interest [P-glycoprotein (P-gp), multidrug resistance protein 1 (MRP1), breast cancer resistance protein (BCRP), lung resistance protein (LRP) and topoisomerase IIα (TOPIIα)], was performed.
YHO-13177 potentiated the cytotoxicity of SN-38, mitoxantrone, and topotecan in both BCRP-transduced human colon cancer HCT116 (HCT116/BCRP) cells and SN-38-resistant human lung cancer A549 (A549/SN4) cells that express BCRP, but had little effect in the parental cells.
These data demonstrate that guanosine affects both the proportion of SP cells and ABCG2 transporters, but the lack of correlation between ABCG2 expression and the SP phenotype indicates that transporters other than ABCG2 are involved in maintaining the SP phenotype in A549 lung cancer cells.
Further, KLF5 knockdown in K-RAS-mutant human lung cancer cells resulted in a fivefold increase in ATP-binding cassette, subfamily G (WHITE), member 2 (ABCG2), an anthracycline drug transporter, which lead to significantly increased resistance to doxorubicin treatment, a chemotherapeutic agent clinically used to treat lung cancer.
In conclusion, this study prioritizes ABCC3 C-211T and ABCG2C421A as candidate transporter SNPs to be further investigated as possible predictors of the clinical outcome of chemotherapy in lung cancer patients.
The BCRP mRNA expression in lung cancer cells and 23 untreated non-small cell lung cancer (NSCLC) tissues was quantitated by real-time reverse transcription-PCR.