scholarly journals The role of ROS and subsequent DNA-damage response in PUMA-induced apoptosis of ovarian cancer cells

Oncotarget ◽  
2017 ◽  
Vol 8 (14) ◽  
pp. 23492-23506 ◽  
Author(s):  
Jun Yang ◽  
Xinyu Zhao ◽  
Mei Tang ◽  
Lei Li ◽  
Yi Lei ◽  
...  
2020 ◽  
Vol 12 ◽  
pp. 175883592098285
Author(s):  
Wenlong Feng ◽  
Dylan C. Dean ◽  
Francis J. Hornicek ◽  
Jinglu Wang ◽  
Yanyan Jia ◽  
...  

Background: Although ataxia-telangiectasia and Rad3 related (ATR) has an established role in the DNA damage response of various cancers, its clinical and prognostic significance in ovarian cancer remains largely unknown. The aims of this study were to assess the expression, function, and clinical prognostic relationship of ATR and phospho-ATR ser428 (p-ATR) in ovarian cancer. Methods: We confirmed ATR and p-ATR expression by immunohistochemistry (IHC) in a unique ovarian cancer tissue microarray constructed of paired primary, recurrent, and metastatic tumor tissues from 26 individual patients. ATR-specific small interfering RNA (siRNA) and ATR inhibitor VE-822 were applied to determine the effects of ATR inhibition on ovarian cancer cell proliferation, apoptosis, and DNA damage. ATR expression and the associated proteins of the ATR/Chk1 pathway in ovarian cancer cell lines were evaluated by Western blotting. The clonogenicity was also examined using clonogenic assays. A three dimensional (3D) cell culture model was performed to mimic the in vivo ovarian cancer environment to further validate the effects of ATR inhibition on ovarian cancer cells. Results: We show recurrent ovarian cancer tissues express higher levels of ATR and p-ATR than their patient-matched primary tumor counterparts. Additionally, higher expression of p-ATR correlates with decreased survival in ovarian cancer patients. Treatment of ovarian cancer cells with ATR specific siRNA or ATR inhibitor VE-822 led to significant apoptosis and inhibition of cellular proliferation, with reduced phosphorylation of Chk1 (p-Chk1), Cdc25c (p-Cdc25c), Cdc2 (p-Cdc2), and increased expression of cleaved PARP and γH2AX. Inhibition of ATR also suppressed clonogenicity and spheroid growth of ovarian cancer cells. Conclusion: Our results support the ATR and p-ATR pathway as a prognostic biomarker, and targeting the ATR machinery is an emerging therapeutic approach in the treatment of ovarian cancer.


2020 ◽  
Author(s):  
wenlong feng ◽  
Dylan C. Dean ◽  
Francis J. Hornicek ◽  
Jinglu Wang ◽  
Yanyan Jia ◽  
...  

Abstract Background: Although ATR has an established role in DNA damage response in various cancers, its clinical and prognostic significance in ovarian cancer remains largely unknown. The aims of this study are to assess the expression, function and clinical prognostic relationship of ATR, p-ATR in ovarian cancer. Methods: We confirmed ATR and p-ATR expressions by immunohistochemistry in a unique ovarian cancer tissue microarray constructed of paired primary, recurrent and metastatic tumor tissues from 26 individual patients. ATR specific siRNA and ATR inhibitor VE-822 were applied to determine the effect of ATR inhibition on ovarian cancer cell proliferation, apoptosis, and DNA damage. ATR expression and the associated proteins of the ATR/Chk1 pathway in ovarian cancer cell lines were evaluated by Western blotting. The clonogenicity was also examined using clonogenic assays. A 3D cell culture model was performed to mimic the in vivo ovarian cancer environment to further validate the effect of ATR inhibition on ovarian cancer cells. Results: We show recurrent ovarian cancer tissues express higher levels of ATR and p-ATR than their patient-matched primary tumor counterparts. Additionally, higher expression of p-ATR correlates with decreased survival in ovarian cancer patients. Treatment of ovarian cancer cells with ATR specific siRNA or ATR inhibitor VE-822 led to significant apoptosis and inhibition of cellular proliferation, with reduced phosphorylation of Chk1 (p-Chk1), Cdc25c (p-Cdc25c), Cdc2 (p-Cdc2), and increased expression of cleaved PARP and γH2AX. Inhibition of ATR also suppressed clonogenicity and spheroid growth of ovarian cancer cells. Conclusion: Our results support the ATR and p-ATR pathway as a prognostic biomarker, and targeting the ATR machinery is an emerging therapeutic approach in the treatment of ovarian cancer.


2018 ◽  
Vol 315 (3) ◽  
pp. F469-F478 ◽  
Author(s):  
Liping Sun ◽  
Jing Liu ◽  
Yanggang Yuan ◽  
Xinzhou Zhang ◽  
Zheng Dong

As a potent chemotherapy drug, cisplatin is also notorious for its side-effects including nephrotoxicity in kidneys, presenting a pressing need to identify renoprotective agents. Cisplatin nephrotoxicity involves epigenetic regulations, including changes in histone acetylation. Bromodomain and extraterminal (BET) proteins are “readers” of the epigenetic code of histone acetylation. Here, we investigated the potential renoprotective effects of JQ1, a small molecule inhibitor of BET proteins. We show that JQ1 significantly ameliorated cisplatin-induced nephrotoxicity in mice as indicated by the measurements of kidney function, histopathology, and renal tubular apoptosis. JQ1 also partially prevented the body weight loss during cisplatin treatment in mice. Consistently, JQ1 inhibited cisplatin-induced apoptosis in renal proximal tubular cells. Mechanistically, JQ1 suppressed cisplatin-induced phosphorylation or activation of p53 and Chk2, key events in DNA damage response. JQ1 also attenuated cisplatin-induced MAP kinase (p38, ERK1/2, and JNK) activation. In addition, JQ1 enhanced the expression of antioxidant genes including nuclear factor erythroid 2-related factor 2 and heme oxygenase-1, while diminishing the expression of the nitrosative protein inducible nitric oxide synthase. JQ1 did not suppress cisplatin-induced apoptosis in A549 nonsmall cell lung cancer cells and AGS gastric cancer cells. These results suggest that JQ1 may protect against cisplatin nephrotoxicity by suppressing DNA damage response, p53, MAP kinases, and oxidative/nitrosative stress pathways.


Chemotherapy ◽  
2018 ◽  
Vol 63 (5) ◽  
pp. 262-271 ◽  
Author(s):  
Yajie Cui ◽  
Li Qin ◽  
Defu Tian ◽  
Ting Wang ◽  
Lijing Fan ◽  
...  

Ovarian cancer is one of the deadliest gynecological malignancies in women. Chemoresistance has been a major obstacle for ovarian cancer treatment. Zinc finger E-box-binding homeobox 1 (ZEB1) is an important regulator of tumor development in various types of cancer. Abnormal expression of SLC3A2 (CD98hc), a type 2 transmembrane cell surface molecule, has been described in several cancers. This study was designed to investigate the role of ZEB1 and SLC3A2 in the chemoresistance to cisplatin in ovarian cancer cells. We found that ZEB1 was increased in cisplatin-resistant SKOV3/DPP cells. Downregulation of ZEB1 significantly decreased cell viability in response to cisplatin, increased cis­platin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. In addition, downregulation of ZEB1 decreased the volume and weight of implanted tumors. SLC3A2 was decreased in cisplatin-resistant SKOV3/DPP cells. Upregulation of SLC3A2 significantly decreased cell viability in response to cisplatin, increased cisplatin-induced apoptosis, and decreased migration and invasion in the presence of cisplatin. Moreover, upregulation of SLC3A2 decreased the volume and weight of implanted tumors. Downregulation of ZEB1 resulted in a significant increase of SLC3A2 expression. Moreover, downregulation of SLC3A2 significantly inhibited ZEB1 knockdown-mediated inhibition of cisplatin-resistance. ZEB1-mediated regulation of SLC3A2 was involved in the chemoresistance to cisplatin in ovarian cancer cells. Overall, we provide new insights into the mechanism of chemoresistance to cisplatin in ovarian cancer cells. ZEB1/SLC3A2 may be promising therapeutic targets for enhancement of the sensitivity of ovarian cancer cells to cisplatin-mediated chemotherapy.


Sign in / Sign up

Export Citation Format

Share Document