TY - JOUR
T1 - HSP70 inhibition synergistically enhances the effects of magnetic fluid hyperthermia in ovarian cancer
AU - Court, Karem A.
AU - Hatakeyama, Hiroto
AU - Wu, Sherry Y.
AU - Lingegowda, Mangala S.
AU - Rodríguez-Aguayo, Cristian
AU - López-Berestein, Gabriel
AU - Ju-Seog, Lee
AU - Rinaldi, Carlos
AU - Juan, Eduardo J.
AU - Sood, Anil K.
AU - Torres-Lugo, Madeline
N1 - Publisher Copyright:
© 2017 AACR.
PY - 2017/5/1
Y1 - 2017/5/1
N2 - Hyperthermia has been investigated as a potential treatment for cancer. However, specificity in hyperthermia application remains a significant challenge. Magnetic fluid hyperthermia (MFH) may be an alternative to surpass such a challenge, but implications of MFH at the cellular level are not well understood. Therefore, the present work focused on the examination of gene expression after MFH treatment and using such information to identify target genes that wheninhibited could produce an enhanced therapeutic outcome after MFH. Genomic analyzes were performed using ovarian cancer cells exposed to MFH for 30 minutes at 43°C, which revealed that heat shock protein (HSP) genes, including HSPA6, were upregulated. HSPA6 encodes the Hsp70, and its expression was confirmed by PCR in HeyA8 and A2780cp20 ovarian cancer cells. Two strategies were investigated to inhibit Hsp70-related genes, siRNA and Hsp70 protein function inhibition by 2-phenylethyenesulfonamide (PES). Both strategies resulted in decreased cell viability following exposure to MFH. Combination index was calculated for PES treatment reporting a synergistic effect. In vivo efficacy experiments with HSPA6 siRNA and MFH were performed using the A2780cp20 and HeyA8 ovarian cancer mouse models. A significantly reduction in tumor growth rate was observed with combination therapy. PES and MFH efficacy were also evaluated in the HeyA8 intraperitoneal tumor model, and resulted in robust antitumor effects. This work demonstrated that HSP70 inhibition combination with MFH generate a synergistic effect and could be a promising target to enhance MFH therapeutic outcomes in ovarian cancer.
AB - Hyperthermia has been investigated as a potential treatment for cancer. However, specificity in hyperthermia application remains a significant challenge. Magnetic fluid hyperthermia (MFH) may be an alternative to surpass such a challenge, but implications of MFH at the cellular level are not well understood. Therefore, the present work focused on the examination of gene expression after MFH treatment and using such information to identify target genes that wheninhibited could produce an enhanced therapeutic outcome after MFH. Genomic analyzes were performed using ovarian cancer cells exposed to MFH for 30 minutes at 43°C, which revealed that heat shock protein (HSP) genes, including HSPA6, were upregulated. HSPA6 encodes the Hsp70, and its expression was confirmed by PCR in HeyA8 and A2780cp20 ovarian cancer cells. Two strategies were investigated to inhibit Hsp70-related genes, siRNA and Hsp70 protein function inhibition by 2-phenylethyenesulfonamide (PES). Both strategies resulted in decreased cell viability following exposure to MFH. Combination index was calculated for PES treatment reporting a synergistic effect. In vivo efficacy experiments with HSPA6 siRNA and MFH were performed using the A2780cp20 and HeyA8 ovarian cancer mouse models. A significantly reduction in tumor growth rate was observed with combination therapy. PES and MFH efficacy were also evaluated in the HeyA8 intraperitoneal tumor model, and resulted in robust antitumor effects. This work demonstrated that HSP70 inhibition combination with MFH generate a synergistic effect and could be a promising target to enhance MFH therapeutic outcomes in ovarian cancer.
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U2 - 10.1158/1535-7163.MCT-16-0519
DO - 10.1158/1535-7163.MCT-16-0519
M3 - Article
C2 - 28223424
AN - SCOPUS:85020009459
SN - 1535-7163
VL - 16
SP - 966
EP - 976
JO - Molecular cancer therapeutics
JF - Molecular cancer therapeutics
IS - 5
ER -