Antisense-mediated downregulation of anti-apoptotic proteins induces apoptosis and sensitizes head and neck squamous cell carcinoma cells to chemotherapy.
We have earlier reported that the inhibition of apoptosis in head and neck squamous cell carcinomas (HNSCC) is because of upregulated expression of Bcl-2, Bcl-X(L) and Survivin. Hence, we addressed the question whether antisense approach towards these inhibitors of apoptosis could restore the apoptosis in HNSCC. Further, we wanted to see whether chemotherapeutic efficacy of Cisplatin and Etoposide could be enhanced by using these drugs in combination with antisense oligonucleotides in human laryngeal carcinoma HeP2 and tongue carcinoma Cal27 cells. The effect of these antisense oligonucleotides was examined on the mRNA expression by RT-PCR and on protein expression by Western blotting. Apoptosis was measured by flowcytometry, TUNEL assay and caspase-3 activity assay. Treatment of HeP2 and Cal27 cells with 400 nM antisense oligonucleotides against Bcl-2, Bcl-X(L) and Survivin for 48 hrs decreased their expression both at the mRNA as well as at the protein level, resulting in the induction of apoptosis. Treatment of HeP2 and Cal27 cells with these antisense oligonucleotides augmented Cisplatin and Etoposide induced apoptosis. Our findings emphasize the importance of Bcl-2, Bcl-X(L) and Survivin as survival factors in HNSCC cells. Antisense treatment against these survival factors in combination with lower doses of chemotherapy offers potential as a less toxic chemoadjuvant therapy.
Sharma
Himani
H
Department of Biochemistry, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
Sen
Sudip
S
Lo Muzio
Lorenzo
L
Mariggiò
Ada
A
Singh
Neeta
N
D000970:Antineoplastic Agents / Q000494:pharmacology; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D053148:Caspase 3; D020169:Caspases / Q000378:metabolism; D002945:Cisplatin / Q000494:pharmacology; D015536:Down-Regulation; D019008:Drug Resistance, Neoplasm; D005047:Etoposide / Q000494:pharmacology; D005434:Flow Cytometry; D006801:Humans; D020287:In Situ Nick-End Labeling; D051034:Inhibitor of Apoptosis Proteins; D007822:Laryngeal Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D008869:Microtubule-Associated Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D009363:Neoplasm Proteins / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077022:Survivin; D014062:Tongue Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D014407:Tumor Cells, Cultured; D051020:bcl-X Protein / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism
D000970:Antineoplastic Agents; D000972:Antineoplastic Agents, Phytogenic; C107489:BIRC5 protein, human; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D016376:Oligonucleotides, Antisense; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D000077022:Survivin; D051020:bcl-X Protein; D005047:Etoposide; C505407:CASP3 protein, human; D053148:Caspase 3; D020169:Caspases; D002945:Cisplatin