Limits...
Adenosine uptake is the major effector of extracellular ATP toxicity in human cervical cancer cells.

Mello Pde A, Filippi-Chiela EC, Nascimento J, Beckenkamp A, Santana DB, Kipper F, Casali EA, Nejar Bruno A, Paccez JD, Zerbini LF, Wink MR, Lenz G, Buffon A - Mol. Biol. Cell (2014)

Bottom Line: Corroborating these data, blockage or knockdown of P2 × 7 only slightly reduced ATP cytotoxicity.Moreover, ATP-induced apoptosis and signaling-p53 increase, AMPK activation, and PARP cleavage-as well as autophagy induction were also inhibited by dipyridamole.In addition, inhibition of adenosine conversion into AMP also blocked cell death, indicating that metabolization of intracellular adenosine originating from extracellular ATP is responsible for the main effects of the latter in human cervical cancer cells.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil.

Show MeSH

Related in: MedlinePlus

P2×7 receptor contributes little to the total cytotoxic effect of extracellular ATP in SiHa cells. (A) Blockage of 5 mM ATP induces cell death by the P2×7 antagonist oATP at two concentrations (300 and 600 μM). Control represents cells without treatment. *p < 0.05 for comparison vs. control and #p < 0.05 for comparison vs. respective group (two-way ANOVA, followed by Bonferroni posttest). (B) Knockdown for P2×7 confirmed by Western blot. SiHa WT, SiHa wild type; SiHa KD ctrl, SiHa cells transduced with nontarget sequence (knockdown control); SiHa KD P2×7, SiHa knockdown for P2×7. Loading control (LC) represents PVDF membrane stained with Coomassie blue. Numbers represent P2×7 protein amount in relation to SiHa WT. (C) Number of viable cells not marked by trypan blue after 5 mM ATP treatment for 24, 48, and 72 h. *p < 0.05 vs. SiHa KD Ctrl and WT at the respective times (one-way ANOVA, followed by Tukey's test).
© Copyright Policy - creative-commons
Related In: Results  -  Collection


getmorefigures.php?uid=PMC4230581&req=5

Figure 4: P2×7 receptor contributes little to the total cytotoxic effect of extracellular ATP in SiHa cells. (A) Blockage of 5 mM ATP induces cell death by the P2×7 antagonist oATP at two concentrations (300 and 600 μM). Control represents cells without treatment. *p < 0.05 for comparison vs. control and #p < 0.05 for comparison vs. respective group (two-way ANOVA, followed by Bonferroni posttest). (B) Knockdown for P2×7 confirmed by Western blot. SiHa WT, SiHa wild type; SiHa KD ctrl, SiHa cells transduced with nontarget sequence (knockdown control); SiHa KD P2×7, SiHa knockdown for P2×7. Loading control (LC) represents PVDF membrane stained with Coomassie blue. Numbers represent P2×7 protein amount in relation to SiHa WT. (C) Number of viable cells not marked by trypan blue after 5 mM ATP treatment for 24, 48, and 72 h. *p < 0.05 vs. SiHa KD Ctrl and WT at the respective times (one-way ANOVA, followed by Tukey's test).

Mentions: This relatively small contribution of P2×7 to cell death was confirmed with the use of a P2×7 antagonist, oxidized ATP (oATP), which only partially prevented the effect of ATP (Figure 4A). To reinforce these findings, P2×7 knockdown (KD) SiHa cells (Figure 4B) were slightly more resistant to ATP than were wild-type (WT) or KD control cells (Figure 4C), confirming the partial role of this receptor in the cytotoxic effect of ATP.


Adenosine uptake is the major effector of extracellular ATP toxicity in human cervical cancer cells.

Mello Pde A, Filippi-Chiela EC, Nascimento J, Beckenkamp A, Santana DB, Kipper F, Casali EA, Nejar Bruno A, Paccez JD, Zerbini LF, Wink MR, Lenz G, Buffon A - Mol. Biol. Cell (2014)

P2×7 receptor contributes little to the total cytotoxic effect of extracellular ATP in SiHa cells. (A) Blockage of 5 mM ATP induces cell death by the P2×7 antagonist oATP at two concentrations (300 and 600 μM). Control represents cells without treatment. *p < 0.05 for comparison vs. control and #p < 0.05 for comparison vs. respective group (two-way ANOVA, followed by Bonferroni posttest). (B) Knockdown for P2×7 confirmed by Western blot. SiHa WT, SiHa wild type; SiHa KD ctrl, SiHa cells transduced with nontarget sequence (knockdown control); SiHa KD P2×7, SiHa knockdown for P2×7. Loading control (LC) represents PVDF membrane stained with Coomassie blue. Numbers represent P2×7 protein amount in relation to SiHa WT. (C) Number of viable cells not marked by trypan blue after 5 mM ATP treatment for 24, 48, and 72 h. *p < 0.05 vs. SiHa KD Ctrl and WT at the respective times (one-way ANOVA, followed by Tukey's test).
© Copyright Policy - creative-commons
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4230581&req=5

Figure 4: P2×7 receptor contributes little to the total cytotoxic effect of extracellular ATP in SiHa cells. (A) Blockage of 5 mM ATP induces cell death by the P2×7 antagonist oATP at two concentrations (300 and 600 μM). Control represents cells without treatment. *p < 0.05 for comparison vs. control and #p < 0.05 for comparison vs. respective group (two-way ANOVA, followed by Bonferroni posttest). (B) Knockdown for P2×7 confirmed by Western blot. SiHa WT, SiHa wild type; SiHa KD ctrl, SiHa cells transduced with nontarget sequence (knockdown control); SiHa KD P2×7, SiHa knockdown for P2×7. Loading control (LC) represents PVDF membrane stained with Coomassie blue. Numbers represent P2×7 protein amount in relation to SiHa WT. (C) Number of viable cells not marked by trypan blue after 5 mM ATP treatment for 24, 48, and 72 h. *p < 0.05 vs. SiHa KD Ctrl and WT at the respective times (one-way ANOVA, followed by Tukey's test).
Mentions: This relatively small contribution of P2×7 to cell death was confirmed with the use of a P2×7 antagonist, oxidized ATP (oATP), which only partially prevented the effect of ATP (Figure 4A). To reinforce these findings, P2×7 knockdown (KD) SiHa cells (Figure 4B) were slightly more resistant to ATP than were wild-type (WT) or KD control cells (Figure 4C), confirming the partial role of this receptor in the cytotoxic effect of ATP.

Bottom Line: Corroborating these data, blockage or knockdown of P2 × 7 only slightly reduced ATP cytotoxicity.Moreover, ATP-induced apoptosis and signaling-p53 increase, AMPK activation, and PARP cleavage-as well as autophagy induction were also inhibited by dipyridamole.In addition, inhibition of adenosine conversion into AMP also blocked cell death, indicating that metabolization of intracellular adenosine originating from extracellular ATP is responsible for the main effects of the latter in human cervical cancer cells.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Biochemical and Cytological Analysis, Faculty of Pharmacy, Federal University of Rio Grande do Sul, Porto Alegre, RS 90610-000, Brazil.

Show MeSH
Related in: MedlinePlus