Abstract
Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) have been strikingly effective in lung cancers harboring activating EGFR mutations. Unfortunately, the cancer cells eventually acquire resistance to EGFR-TKI. Approximately 50% of the acquired resistance involves a secondary T790M mutation. To overcome the resistance, we focused on EGFR suppression using microRNA-7 (miR-7), targeting multiple sites in the 3′-untranslated region of EGFR mRNA. Two EGFR-TKI-sensitive cell lines (PC-9 and H3255) and two EGFR-TKI-resistant cell lines harboring T790M (RPC-9 and H1975) were used. We constructed miR-7-2 containing miR-7-expressing plasmid. After transfection of the miR-7-expressing plasmid, using cationic liposomes, a quantitative PCR and dual luciferase assay were conducted to examine the efficacy. The antiproliferative effect was evaluated using a cell count assay and xenograft model. Protein expression was examined by Western blotting. The miR-7 expression level of the transfectants was approximately 30-fold higher, and the luciferase activity was ablated by 92%. miR-7 significantly inhibited cell growth not only in PC-9 and H3255 but also in RPC-9 and H1975. Expression of insulin receptor substrate-1 (IRS-1), RAF-1, and EGFR was suppressed in the four cell lines. Injection of the miR-7-expressing plasmid revealed marked tumor regression in a mouse xenograft model using RPC-9 and H1975. EGFR, RAF-1, and IRS-1 were suppressed in the residual tumors. These findings indicate promising therapeutic applications of miR-7-expressing plasmids against EGFR oncogene-addicted lung cancers including T790M resistance by liposomal delivery.
| Original language | English |
|---|---|
| Pages (from-to) | 1720-1727 |
| Number of pages | 8 |
| Journal | Molecular Cancer Therapeutics |
| Volume | 10 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - Sep 2011 |
Fingerprint
ASJC Scopus subject areas
- Oncology
- Cancer Research
Cite this
Liposomal delivery of MicroRNA-7-expressing plasmid overcomes epidermal growth factor receptor tyrosine kinase inhibitor-resistance in lung cancer cells. / Rai, Kanmei; Takigawa, Nagio; Itou, Sachio; Kashihara, Hiromi; Ichihara, Eiki; Yasuda, Tatsuji; Shimizu, Kenji; Tanimoto, Mitsune; Kiura, Katsuyuki.
In: Molecular Cancer Therapeutics, Vol. 10, No. 9, 09.2011, p. 1720-1727.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Liposomal delivery of MicroRNA-7-expressing plasmid overcomes epidermal growth factor receptor tyrosine kinase inhibitor-resistance in lung cancer cells
AU - Rai, Kanmei
AU - Takigawa, Nagio
AU - Itou, Sachio
AU - Kashihara, Hiromi
AU - Ichihara, Eiki
AU - Yasuda, Tatsuji
AU - Shimizu, Kenji
AU - Tanimoto, Mitsune
AU - Kiura, Katsuyuki
PY - 2011/9
Y1 - 2011/9
N2 - Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) have been strikingly effective in lung cancers harboring activating EGFR mutations. Unfortunately, the cancer cells eventually acquire resistance to EGFR-TKI. Approximately 50% of the acquired resistance involves a secondary T790M mutation. To overcome the resistance, we focused on EGFR suppression using microRNA-7 (miR-7), targeting multiple sites in the 3′-untranslated region of EGFR mRNA. Two EGFR-TKI-sensitive cell lines (PC-9 and H3255) and two EGFR-TKI-resistant cell lines harboring T790M (RPC-9 and H1975) were used. We constructed miR-7-2 containing miR-7-expressing plasmid. After transfection of the miR-7-expressing plasmid, using cationic liposomes, a quantitative PCR and dual luciferase assay were conducted to examine the efficacy. The antiproliferative effect was evaluated using a cell count assay and xenograft model. Protein expression was examined by Western blotting. The miR-7 expression level of the transfectants was approximately 30-fold higher, and the luciferase activity was ablated by 92%. miR-7 significantly inhibited cell growth not only in PC-9 and H3255 but also in RPC-9 and H1975. Expression of insulin receptor substrate-1 (IRS-1), RAF-1, and EGFR was suppressed in the four cell lines. Injection of the miR-7-expressing plasmid revealed marked tumor regression in a mouse xenograft model using RPC-9 and H1975. EGFR, RAF-1, and IRS-1 were suppressed in the residual tumors. These findings indicate promising therapeutic applications of miR-7-expressing plasmids against EGFR oncogene-addicted lung cancers including T790M resistance by liposomal delivery.
AB - Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) have been strikingly effective in lung cancers harboring activating EGFR mutations. Unfortunately, the cancer cells eventually acquire resistance to EGFR-TKI. Approximately 50% of the acquired resistance involves a secondary T790M mutation. To overcome the resistance, we focused on EGFR suppression using microRNA-7 (miR-7), targeting multiple sites in the 3′-untranslated region of EGFR mRNA. Two EGFR-TKI-sensitive cell lines (PC-9 and H3255) and two EGFR-TKI-resistant cell lines harboring T790M (RPC-9 and H1975) were used. We constructed miR-7-2 containing miR-7-expressing plasmid. After transfection of the miR-7-expressing plasmid, using cationic liposomes, a quantitative PCR and dual luciferase assay were conducted to examine the efficacy. The antiproliferative effect was evaluated using a cell count assay and xenograft model. Protein expression was examined by Western blotting. The miR-7 expression level of the transfectants was approximately 30-fold higher, and the luciferase activity was ablated by 92%. miR-7 significantly inhibited cell growth not only in PC-9 and H3255 but also in RPC-9 and H1975. Expression of insulin receptor substrate-1 (IRS-1), RAF-1, and EGFR was suppressed in the four cell lines. Injection of the miR-7-expressing plasmid revealed marked tumor regression in a mouse xenograft model using RPC-9 and H1975. EGFR, RAF-1, and IRS-1 were suppressed in the residual tumors. These findings indicate promising therapeutic applications of miR-7-expressing plasmids against EGFR oncogene-addicted lung cancers including T790M resistance by liposomal delivery.
UR - http://www.scopus.com/inward/record.url?scp=80052698948&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80052698948&partnerID=8YFLogxK
U2 - 10.1158/1535-7163.MCT-11-0220
DO - 10.1158/1535-7163.MCT-11-0220
M3 - Article
C2 - 21712475
AN - SCOPUS:80052698948
VL - 10
SP - 1720
EP - 1727
JO - Molecular Cancer Therapeutics
JF - Molecular Cancer Therapeutics
SN - 1535-7163
IS - 9
ER -