Increased adenoviral transduction efficacy in human laryngeal carcinoma cells resistant to cisplatin is associated with increased expression of integrin αvβ3 and coxsackie adenovirus receptor

✍ Scribed by Andreja Ambriović-Ristov; Jelka Gabrilovac; Tamara Čimbora-Zovko; Maja Osmak

• Publisher: John Wiley and Sons
• Year: 2004
• Tongue: French
• Weight: 206 KB
• Volume: 110
• Category: Article
• ISSN: 0020-7136
• DOI: 10.1002/ijc.20176

✦ Synopsis

In our study, we investigated molecular mechanisms of increased adenoviral transduction efficacy in cisplatin-resistant human laryngeal carcinoma cells CA3 ST as compared to parental cells HEp2. Using reverse transcription-PCR, the genes potentially implicated in adenoviral entry were screened. In cisplatin-resistant cells, only upregulation of ␣ v ␤ 3 integrin was detected, which was additionally confirmed by flow cytometry. Moderately increased expression of CAR was determined in cisplatin-resistant CA3 ST cells using flow cytometry and measurement of wild-type adenovirus Ad5CMV␤gal attachment. In order to test the implication of ␣ v ␤ 3 integrin in transduction efficacy, 6 HEp2-derived ␣ v ␤ 3expressing clones with graded expression of ␣ v ␤ 3 were isolated. To a certain degree of density, expression of ␣ v ␤ 3 positively correlated with Ad5CMV␤gal transduction efficacy (i.e., increased viral transduction), suggesting a role of ␣ v ␤ 3 in transduction efficacy. However, HEp2 clones with the highest ␣ v ␤ 3 expression were negatively correlated with transduction efficacy (i.e., decreased viral transduction). This was shown to be associated with downregulation of ␣ v ␤ 5 integrin, also involved in viral transduction, in clones with the highest ␣ v ␤ 3 expression. The implication of CAR in increased adenoviral transduction efficacy in cisplatin resistant CA3 ST cells was further assessed by transduction experiments using adenoviral mutant Ad5Fb⌬639 whose entry is only to a very small extent dependent on the presence of CAR. Indeed, Ad5Fb⌬639 infected 2.5-fold more, in comparison to wildtype adenovirus, which infected 5-fold more efficiently resistant CA3 ST cells than parental HEp2 cells, indicating that increased expression of CAR contributes to increased efficacy of adenoviral transduction. Thus, the data presented provide evidence that both ␣ v ␤ 3 integrin and CAR are involved in increased adenoviral transduction efficacy in cisplatin resistant CA3 ST cells. These findings may have significant implications in human gene therapy using adenoviruses, especially in patients after unsuccessful cisplatin treatment.