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XAV939-mediated ARTD activity inhibition in human MB cell lines.

Renna C, Salaroli R, Cocchi C, Cenacchi G - PLoS ONE (2015)

Bottom Line: XAV939 inhibited the WNT pathway and DNA-PKcs in our MB cells, with many biological consequences.The co-administration of XAV939 and ionizing radiations (IR) inhibited MB cells proliferation and clonogenic capacity, decreased their efficacy in repairing DNA damage, and increased IR-induced cell mortality.In conclusion, our in vitro data show that XAV939 could be a very promising small molecule in MB treatment, and these results lay the basis for further in vivo studies with the aim of improving the current therapy available for MB patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum University of Bologna, Bologna, Italy.

ABSTRACT
Diphtheria toxin-like ADP-ribosyltransferases 1 and 5 (ARTD-1, ARTD-5) are poly ADP-ribose enzymes (PARP) involved in non-homologous end-joining (NHEJ), which is the major pathway of double-strand break (DSB) repair. In addition, ARTD-5, or Tankyrase (TNKS), is a positive regulator of the WNT signaling implicated in the development and biological behavior of many neoplasms, such as Medulloblastoma (MB), in which radiotherapy is an essential part of the treatment. The use of radiosensitizing agents may improve the therapeutic index in MB patients by increasing the efficacy of radiotherapy, while reducing toxicity to the neuroaxis. ARTD-5 seems to be a good molecular target for improving the current treatment of MB. In this study, we used the small molecule XAV939, a potent ARTD-5 inhibitor with a slight affinity for ARTD-1, in different human MB cell lines. XAV939 inhibited the WNT pathway and DNA-PKcs in our MB cells, with many biological consequences. The co-administration of XAV939 and ionizing radiations (IR) inhibited MB cells proliferation and clonogenic capacity, decreased their efficacy in repairing DNA damage, and increased IR-induced cell mortality. In conclusion, our in vitro data show that XAV939 could be a very promising small molecule in MB treatment, and these results lay the basis for further in vivo studies with the aim of improving the current therapy available for MB patients.

No MeSH data available.


Related in: MedlinePlus

XAV939 inhibits TNKS PARP-activity in MB cell lines.WB analysis and densitometry of total and nuclear MB cells extracts after XAV939 treatment: MB cell lines (DAOY, ONS-76) were treated with 5 μM XAV939 or with an equal volume of DMSO. A. Both cell lines showed an increase in total Axin protein levels at 8 h after treatment (80% and 70% respectively in ONS-76 and DAOY compared to DMSO treated control, p <. 05), followed by a β-catenin decrease in total (30%, p <. 05) and, in particular, in nuclear extracts, at 16 h after drug administration (80% reduction compared with control, p <. 001). B. XAV939 induced a DNA-PKcs protein level reduction of about 40% at 8 h and 16 h after treatment compared to non-treated control cells (p <. 05 in A, p <. 01 in B). Densitometry data (mean ± s.e.) were normalized with β-actin (for total extracts) and lamin-b (for nuclear extracts) and are representative of the results derived from three independent experiments.
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pone.0124149.g001: XAV939 inhibits TNKS PARP-activity in MB cell lines.WB analysis and densitometry of total and nuclear MB cells extracts after XAV939 treatment: MB cell lines (DAOY, ONS-76) were treated with 5 μM XAV939 or with an equal volume of DMSO. A. Both cell lines showed an increase in total Axin protein levels at 8 h after treatment (80% and 70% respectively in ONS-76 and DAOY compared to DMSO treated control, p <. 05), followed by a β-catenin decrease in total (30%, p <. 05) and, in particular, in nuclear extracts, at 16 h after drug administration (80% reduction compared with control, p <. 001). B. XAV939 induced a DNA-PKcs protein level reduction of about 40% at 8 h and 16 h after treatment compared to non-treated control cells (p <. 05 in A, p <. 01 in B). Densitometry data (mean ± s.e.) were normalized with β-actin (for total extracts) and lamin-b (for nuclear extracts) and are representative of the results derived from three independent experiments.

Mentions: XAV939 is known to induce WNT signaling inhibition by increasing Axin protein levels, thereby promoting β-catenin degradation [14]. We found an effective increase in total Axin levels, 8 h after treatment with XAV939 (5 μM) and a decrease in β-catenin protein levels, both in total and in nuclear extracts, at 16 h. Densitometry analyses revealed a 70% increase of total Axin protein levels in DAOY cells and an 80% increase in ONS-76 cells, treated with XAV939 (5 μM) compared to DMSO treated control cells. Total β-catenin protein levels decreased by about 30% in both cell lines compared to controls; whereas, in nuclear fraction, we found an 80% reduction of β-catenin levels (Fig 1A).


XAV939-mediated ARTD activity inhibition in human MB cell lines.

Renna C, Salaroli R, Cocchi C, Cenacchi G - PLoS ONE (2015)

XAV939 inhibits TNKS PARP-activity in MB cell lines.WB analysis and densitometry of total and nuclear MB cells extracts after XAV939 treatment: MB cell lines (DAOY, ONS-76) were treated with 5 μM XAV939 or with an equal volume of DMSO. A. Both cell lines showed an increase in total Axin protein levels at 8 h after treatment (80% and 70% respectively in ONS-76 and DAOY compared to DMSO treated control, p <. 05), followed by a β-catenin decrease in total (30%, p <. 05) and, in particular, in nuclear extracts, at 16 h after drug administration (80% reduction compared with control, p <. 001). B. XAV939 induced a DNA-PKcs protein level reduction of about 40% at 8 h and 16 h after treatment compared to non-treated control cells (p <. 05 in A, p <. 01 in B). Densitometry data (mean ± s.e.) were normalized with β-actin (for total extracts) and lamin-b (for nuclear extracts) and are representative of the results derived from three independent experiments.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4383513&req=5

pone.0124149.g001: XAV939 inhibits TNKS PARP-activity in MB cell lines.WB analysis and densitometry of total and nuclear MB cells extracts after XAV939 treatment: MB cell lines (DAOY, ONS-76) were treated with 5 μM XAV939 or with an equal volume of DMSO. A. Both cell lines showed an increase in total Axin protein levels at 8 h after treatment (80% and 70% respectively in ONS-76 and DAOY compared to DMSO treated control, p <. 05), followed by a β-catenin decrease in total (30%, p <. 05) and, in particular, in nuclear extracts, at 16 h after drug administration (80% reduction compared with control, p <. 001). B. XAV939 induced a DNA-PKcs protein level reduction of about 40% at 8 h and 16 h after treatment compared to non-treated control cells (p <. 05 in A, p <. 01 in B). Densitometry data (mean ± s.e.) were normalized with β-actin (for total extracts) and lamin-b (for nuclear extracts) and are representative of the results derived from three independent experiments.
Mentions: XAV939 is known to induce WNT signaling inhibition by increasing Axin protein levels, thereby promoting β-catenin degradation [14]. We found an effective increase in total Axin levels, 8 h after treatment with XAV939 (5 μM) and a decrease in β-catenin protein levels, both in total and in nuclear extracts, at 16 h. Densitometry analyses revealed a 70% increase of total Axin protein levels in DAOY cells and an 80% increase in ONS-76 cells, treated with XAV939 (5 μM) compared to DMSO treated control cells. Total β-catenin protein levels decreased by about 30% in both cell lines compared to controls; whereas, in nuclear fraction, we found an 80% reduction of β-catenin levels (Fig 1A).

Bottom Line: XAV939 inhibited the WNT pathway and DNA-PKcs in our MB cells, with many biological consequences.The co-administration of XAV939 and ionizing radiations (IR) inhibited MB cells proliferation and clonogenic capacity, decreased their efficacy in repairing DNA damage, and increased IR-induced cell mortality.In conclusion, our in vitro data show that XAV939 could be a very promising small molecule in MB treatment, and these results lay the basis for further in vivo studies with the aim of improving the current therapy available for MB patients.

View Article: PubMed Central - PubMed

Affiliation: Department of Biomedical and Neuromotor Sciences, Alma Mater Studiorum University of Bologna, Bologna, Italy.

ABSTRACT
Diphtheria toxin-like ADP-ribosyltransferases 1 and 5 (ARTD-1, ARTD-5) are poly ADP-ribose enzymes (PARP) involved in non-homologous end-joining (NHEJ), which is the major pathway of double-strand break (DSB) repair. In addition, ARTD-5, or Tankyrase (TNKS), is a positive regulator of the WNT signaling implicated in the development and biological behavior of many neoplasms, such as Medulloblastoma (MB), in which radiotherapy is an essential part of the treatment. The use of radiosensitizing agents may improve the therapeutic index in MB patients by increasing the efficacy of radiotherapy, while reducing toxicity to the neuroaxis. ARTD-5 seems to be a good molecular target for improving the current treatment of MB. In this study, we used the small molecule XAV939, a potent ARTD-5 inhibitor with a slight affinity for ARTD-1, in different human MB cell lines. XAV939 inhibited the WNT pathway and DNA-PKcs in our MB cells, with many biological consequences. The co-administration of XAV939 and ionizing radiations (IR) inhibited MB cells proliferation and clonogenic capacity, decreased their efficacy in repairing DNA damage, and increased IR-induced cell mortality. In conclusion, our in vitro data show that XAV939 could be a very promising small molecule in MB treatment, and these results lay the basis for further in vivo studies with the aim of improving the current therapy available for MB patients.

No MeSH data available.


Related in: MedlinePlus