Limits...
Combined treatment with an oncolytic adenovirus and antitumor activity of vincristine against retinoblastoma cells.

Song X, Wang H, Jia R, Cun B, Zhao X, Zhou Y, Xu X, Qian G, Ge S, Fan X - Int J Mol Sci (2012)

Bottom Line: The combination therapy exerted a synergistic antitumor effect via a type of G(2)/M and S phase arrest rather than the induction of apoptosis.The combination of VCR and SG600 further reduced Akt phosphorylation compared with cells treated with VCR alone, suggesting that SG600 could overcome chemoresistance, perhaps by down-regulating Akt in RB cells.An increase in the expression of p-p53 and decrease in p-Rb expression in HXO-RB(44) after co-treatment might be associated with cell cycle block.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China; E-Mails: songxin0521@hotmail.com (X.S.); jrb6@sina.com (R.J.); catherine1_2_3@163.com (B.C.); zxp0856@sina.com (X.Z.); zhouyixiong21@gmail.com (Y.Z.); xuxu0139@hotmail.com (X.X.).

ABSTRACT
Treatment trends of retinoblastoma (RB) have gradually evolved from eye enucleation and external radiation to local treatment. Combined treatment with an oncolytic virus and chemotherapy is currently a new method in RB treatment. To investigate the therapeutic effect of oncolytic adenovirus SG600 in combination with vincristine (VCR) on retinoblastoma in vitro, the cell viability, cell cycle effects and apoptotic activity of HXO-RB(44) cells treated with SG600, VCR or SG600 plus VCR were measured using a cell counting kit-8-based procedure and flow cytometry. Western blot analysis for Akt, p-Akt, p-p53 and p-Rb protein was performed to investigate the underlying mechanisms of combined therapy. The combination therapy exerted a synergistic antitumor effect via a type of G(2)/M and S phase arrest rather than the induction of apoptosis. The combination of VCR and SG600 further reduced Akt phosphorylation compared with cells treated with VCR alone, suggesting that SG600 could overcome chemoresistance, perhaps by down-regulating Akt in RB cells. An increase in the expression of p-p53 and decrease in p-Rb expression in HXO-RB(44) after co-treatment might be associated with cell cycle block. Western blot examination revealed that VCR might enhance SG600 replication. These results suggest that viro-chemo combination therapy is a feasible and potentially promising approach for the treatment of retinoblastoma.

No MeSH data available.


Related in: MedlinePlus

Representative FACS histograms showing the cell cycle distribution in HXO-RB44 cells following different treatments. (A) Cell cycle analysis was performed by quantifying propidium iodide (PI) incorporation by flow cytometry. DNA content and number of events were analyzed after different treatments for 48 h; (B) relative changes in the percentage in each cell cycle phase were plotted after PI staining and FACS analysis. Results are representative of three independent experiments (** p < 0.01, compared with S and G2/M phases of HXO-RB44 treated with 5 nM VCR). NC (negative control): treatment with PBS.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC3472711&req=5

f3-ijms-13-10736: Representative FACS histograms showing the cell cycle distribution in HXO-RB44 cells following different treatments. (A) Cell cycle analysis was performed by quantifying propidium iodide (PI) incorporation by flow cytometry. DNA content and number of events were analyzed after different treatments for 48 h; (B) relative changes in the percentage in each cell cycle phase were plotted after PI staining and FACS analysis. Results are representative of three independent experiments (** p < 0.01, compared with S and G2/M phases of HXO-RB44 treated with 5 nM VCR). NC (negative control): treatment with PBS.

Mentions: We next investigated whether our treatment scheme would affect the cell cycle. Following PI staining, cell cycle distribution analysis of HXO-RB44 cells was conducted 48 h later by flow cytometry. As shown in Figure 3, VCR (5 nM) led to increased cell cycle arrest in the S phase at 48 h post-treatment, whereas SG600 induced cell cycle arrest in the G2/M phase at 48 h post-treatment. In the co-treatment group, the cell cycle distribution exhibited a combination of the findings seen in the two monotherapy groups, with a moderate increase in the G2/M phase compared with the group treated with VCR (** p < 0.01).


Combined treatment with an oncolytic adenovirus and antitumor activity of vincristine against retinoblastoma cells.

Song X, Wang H, Jia R, Cun B, Zhao X, Zhou Y, Xu X, Qian G, Ge S, Fan X - Int J Mol Sci (2012)

Representative FACS histograms showing the cell cycle distribution in HXO-RB44 cells following different treatments. (A) Cell cycle analysis was performed by quantifying propidium iodide (PI) incorporation by flow cytometry. DNA content and number of events were analyzed after different treatments for 48 h; (B) relative changes in the percentage in each cell cycle phase were plotted after PI staining and FACS analysis. Results are representative of three independent experiments (** p < 0.01, compared with S and G2/M phases of HXO-RB44 treated with 5 nM VCR). NC (negative control): treatment with PBS.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC3472711&req=5

f3-ijms-13-10736: Representative FACS histograms showing the cell cycle distribution in HXO-RB44 cells following different treatments. (A) Cell cycle analysis was performed by quantifying propidium iodide (PI) incorporation by flow cytometry. DNA content and number of events were analyzed after different treatments for 48 h; (B) relative changes in the percentage in each cell cycle phase were plotted after PI staining and FACS analysis. Results are representative of three independent experiments (** p < 0.01, compared with S and G2/M phases of HXO-RB44 treated with 5 nM VCR). NC (negative control): treatment with PBS.
Mentions: We next investigated whether our treatment scheme would affect the cell cycle. Following PI staining, cell cycle distribution analysis of HXO-RB44 cells was conducted 48 h later by flow cytometry. As shown in Figure 3, VCR (5 nM) led to increased cell cycle arrest in the S phase at 48 h post-treatment, whereas SG600 induced cell cycle arrest in the G2/M phase at 48 h post-treatment. In the co-treatment group, the cell cycle distribution exhibited a combination of the findings seen in the two monotherapy groups, with a moderate increase in the G2/M phase compared with the group treated with VCR (** p < 0.01).

Bottom Line: The combination therapy exerted a synergistic antitumor effect via a type of G(2)/M and S phase arrest rather than the induction of apoptosis.The combination of VCR and SG600 further reduced Akt phosphorylation compared with cells treated with VCR alone, suggesting that SG600 could overcome chemoresistance, perhaps by down-regulating Akt in RB cells.An increase in the expression of p-p53 and decrease in p-Rb expression in HXO-RB(44) after co-treatment might be associated with cell cycle block.

View Article: PubMed Central - PubMed

Affiliation: Department of Ophthalmology, Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011, China; E-Mails: songxin0521@hotmail.com (X.S.); jrb6@sina.com (R.J.); catherine1_2_3@163.com (B.C.); zxp0856@sina.com (X.Z.); zhouyixiong21@gmail.com (Y.Z.); xuxu0139@hotmail.com (X.X.).

ABSTRACT
Treatment trends of retinoblastoma (RB) have gradually evolved from eye enucleation and external radiation to local treatment. Combined treatment with an oncolytic virus and chemotherapy is currently a new method in RB treatment. To investigate the therapeutic effect of oncolytic adenovirus SG600 in combination with vincristine (VCR) on retinoblastoma in vitro, the cell viability, cell cycle effects and apoptotic activity of HXO-RB(44) cells treated with SG600, VCR or SG600 plus VCR were measured using a cell counting kit-8-based procedure and flow cytometry. Western blot analysis for Akt, p-Akt, p-p53 and p-Rb protein was performed to investigate the underlying mechanisms of combined therapy. The combination therapy exerted a synergistic antitumor effect via a type of G(2)/M and S phase arrest rather than the induction of apoptosis. The combination of VCR and SG600 further reduced Akt phosphorylation compared with cells treated with VCR alone, suggesting that SG600 could overcome chemoresistance, perhaps by down-regulating Akt in RB cells. An increase in the expression of p-p53 and decrease in p-Rb expression in HXO-RB(44) after co-treatment might be associated with cell cycle block. Western blot examination revealed that VCR might enhance SG600 replication. These results suggest that viro-chemo combination therapy is a feasible and potentially promising approach for the treatment of retinoblastoma.

No MeSH data available.


Related in: MedlinePlus