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KSP inhibitor ARRY-520 as a substitute for Paclitaxel in Type I ovarian cancer cells.

Kim KH, Xie Y, Tytler EM, Woessner R, Mor G, Alvero AB - J Transl Med (2009)

Bottom Line: ARRY-520 and Paclitaxel exhibited the same cytotoxic effect on Type I and II cells.Unlike Paclitaxel, ARRY-520 did not induce NF-kappaB activation, did not enhance cytokine secretion, nor induce ERK phosphorylation in Type I EOC cells.However, unlike Paclitaxel, it does not induce these pro-tumor effects in Type I cells.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA. ghkim@pusan.ac.kr

ABSTRACT

Background: We previously described a sub-population of epithelial ovarian cancer (EOC) cells with a functional TLR-4/MyD88/NF-kappaB pathway (Type I EOC cells), which confers the capacity to respond to Paclitaxel, a known TLR-4 ligand, by enhancing NF-kappaB activity and upregulating cytokine secretion - events that are known to promote tumor progression. It is therefore important to distinguish those patients that should not receive Paclitaxel; it is also important to identify alternative chemotherapy options that would benefit this sub-group of patients. The objective of this study is to determine if the KSP inhibitor, ARRY-520, can be a substitute for Paclitaxel in patients with Type I EOC.

Methods: EOC cells isolated from either ascites or tumor tissue were treated with increasing concentrations of ARRY-520 or Paclitaxel and cell viability determined. Activation of the apoptotic pathway was determined using Western blot analysis. Mitochondrial integrity was quantified using JC1 dye. Cytokine profiling was performed from supernatants using xMAP technology. NF-kappaB activity was measured using a Luciferase reporter system. In vivo activity was determined using a subcutaneous xenograft mouse model.

Results: ARRY-520 and Paclitaxel exhibited the same cytotoxic effect on Type I and II cells. The GI50 at 48 h for Type II EOC cells was 0.0015 microM and 0.2 microM for ARRY-520 and Paclitaxel, respectively. For Type I EOC cells, the GI50 at 48 h was > 3 microM and >20 microM for ARRY-520 and Paclitaxel, respectively. Decrease in the number of viable cells was accompanied by mitochondrial depolarization and caspase activation. Unlike Paclitaxel, ARRY-520 did not induce NF-kappaB activation, did not enhance cytokine secretion, nor induce ERK phosphorylation in Type I EOC cells.

Conclusion: Administration of Paclitaxel to patients with high percentage Type I cancer cells could have detrimental effects due to Paclitaxel-induced enhancement of NF-kappaB and ERK activities, and cytokine production (e.g. IL-6), which promote chemoresistance and tumor progression. ARRY-520 has similar anti-tumor activity in EOC cells as that of Paclitaxel. However, unlike Paclitaxel, it does not induce these pro-tumor effects in Type I cells. Therefore, the KSP inhibitor ARRY-520 may represent an alternative to Paclitaxel in this subgroup of EOC patients.

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ARRY-520 significantly decreases the number of viable Type II EOC cells. The viability (in percentage, normalized to untreated cells) of EOC cells after treatment with increasing concentrations of ARRY-520 for (a) 24 and (b) 48 hours. Data were compiled from at least three independent experiments, each done in triplicate. Type I cells – R182, 01–19b, R1140; Type II cells – A2780, CP70, 01–28; dotted line corresponds to 50% viability.
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Figure 1: ARRY-520 significantly decreases the number of viable Type II EOC cells. The viability (in percentage, normalized to untreated cells) of EOC cells after treatment with increasing concentrations of ARRY-520 for (a) 24 and (b) 48 hours. Data were compiled from at least three independent experiments, each done in triplicate. Type I cells – R182, 01–19b, R1140; Type II cells – A2780, CP70, 01–28; dotted line corresponds to 50% viability.

Mentions: Our first objective was to determine the effect of ARRY-520 on EOC cells. Thus, two established EOC cell lines (A2780, CP70) and four EOC cell cultures isolated from malignant ovarian ascites (R182, 01–28, 01–19b, R1140) were treated with increasing concentrations of ARRY-520 (up to 3 μM) or Paclitaxel (up to 20 μM) for 24 and 48 hours and cell viability was determined using the CellTiter 96 AQueous One Solution Cell Proliferation Assay. ARRY-520 effectively decreased cell viability in a time-dependent manner in the Type II EOC cell lines A2780, CP70, and 01–28 but had minimal effect on Paclitaxel-resistant Type I EOC cell lines R182, 01–19b, and R1140 (Fig. 1A–B). In Type II cell lines, the most prominent effect on cell viability was observed following 48 hours of treatment, with 50% growth inhibition (GI50) observed at 1.5 nM. At the same time-point, the GI50 for Type I cells was > 3,000 nM. Interestingly, we saw a similar pattern of response with equivalent pharmacologic doses of Paclitaxel. As shown in Table 1, GI50 was not reached in either compound in Type I EOC cells.


KSP inhibitor ARRY-520 as a substitute for Paclitaxel in Type I ovarian cancer cells.

Kim KH, Xie Y, Tytler EM, Woessner R, Mor G, Alvero AB - J Transl Med (2009)

ARRY-520 significantly decreases the number of viable Type II EOC cells. The viability (in percentage, normalized to untreated cells) of EOC cells after treatment with increasing concentrations of ARRY-520 for (a) 24 and (b) 48 hours. Data were compiled from at least three independent experiments, each done in triplicate. Type I cells – R182, 01–19b, R1140; Type II cells – A2780, CP70, 01–28; dotted line corresponds to 50% viability.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2719595&req=5

Figure 1: ARRY-520 significantly decreases the number of viable Type II EOC cells. The viability (in percentage, normalized to untreated cells) of EOC cells after treatment with increasing concentrations of ARRY-520 for (a) 24 and (b) 48 hours. Data were compiled from at least three independent experiments, each done in triplicate. Type I cells – R182, 01–19b, R1140; Type II cells – A2780, CP70, 01–28; dotted line corresponds to 50% viability.
Mentions: Our first objective was to determine the effect of ARRY-520 on EOC cells. Thus, two established EOC cell lines (A2780, CP70) and four EOC cell cultures isolated from malignant ovarian ascites (R182, 01–28, 01–19b, R1140) were treated with increasing concentrations of ARRY-520 (up to 3 μM) or Paclitaxel (up to 20 μM) for 24 and 48 hours and cell viability was determined using the CellTiter 96 AQueous One Solution Cell Proliferation Assay. ARRY-520 effectively decreased cell viability in a time-dependent manner in the Type II EOC cell lines A2780, CP70, and 01–28 but had minimal effect on Paclitaxel-resistant Type I EOC cell lines R182, 01–19b, and R1140 (Fig. 1A–B). In Type II cell lines, the most prominent effect on cell viability was observed following 48 hours of treatment, with 50% growth inhibition (GI50) observed at 1.5 nM. At the same time-point, the GI50 for Type I cells was > 3,000 nM. Interestingly, we saw a similar pattern of response with equivalent pharmacologic doses of Paclitaxel. As shown in Table 1, GI50 was not reached in either compound in Type I EOC cells.

Bottom Line: ARRY-520 and Paclitaxel exhibited the same cytotoxic effect on Type I and II cells.Unlike Paclitaxel, ARRY-520 did not induce NF-kappaB activation, did not enhance cytokine secretion, nor induce ERK phosphorylation in Type I EOC cells.However, unlike Paclitaxel, it does not induce these pro-tumor effects in Type I cells.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA. ghkim@pusan.ac.kr

ABSTRACT

Background: We previously described a sub-population of epithelial ovarian cancer (EOC) cells with a functional TLR-4/MyD88/NF-kappaB pathway (Type I EOC cells), which confers the capacity to respond to Paclitaxel, a known TLR-4 ligand, by enhancing NF-kappaB activity and upregulating cytokine secretion - events that are known to promote tumor progression. It is therefore important to distinguish those patients that should not receive Paclitaxel; it is also important to identify alternative chemotherapy options that would benefit this sub-group of patients. The objective of this study is to determine if the KSP inhibitor, ARRY-520, can be a substitute for Paclitaxel in patients with Type I EOC.

Methods: EOC cells isolated from either ascites or tumor tissue were treated with increasing concentrations of ARRY-520 or Paclitaxel and cell viability determined. Activation of the apoptotic pathway was determined using Western blot analysis. Mitochondrial integrity was quantified using JC1 dye. Cytokine profiling was performed from supernatants using xMAP technology. NF-kappaB activity was measured using a Luciferase reporter system. In vivo activity was determined using a subcutaneous xenograft mouse model.

Results: ARRY-520 and Paclitaxel exhibited the same cytotoxic effect on Type I and II cells. The GI50 at 48 h for Type II EOC cells was 0.0015 microM and 0.2 microM for ARRY-520 and Paclitaxel, respectively. For Type I EOC cells, the GI50 at 48 h was > 3 microM and >20 microM for ARRY-520 and Paclitaxel, respectively. Decrease in the number of viable cells was accompanied by mitochondrial depolarization and caspase activation. Unlike Paclitaxel, ARRY-520 did not induce NF-kappaB activation, did not enhance cytokine secretion, nor induce ERK phosphorylation in Type I EOC cells.

Conclusion: Administration of Paclitaxel to patients with high percentage Type I cancer cells could have detrimental effects due to Paclitaxel-induced enhancement of NF-kappaB and ERK activities, and cytokine production (e.g. IL-6), which promote chemoresistance and tumor progression. ARRY-520 has similar anti-tumor activity in EOC cells as that of Paclitaxel. However, unlike Paclitaxel, it does not induce these pro-tumor effects in Type I cells. Therefore, the KSP inhibitor ARRY-520 may represent an alternative to Paclitaxel in this subgroup of EOC patients.

Show MeSH
Related in: MedlinePlus