Novel biomarker of specific castration-resistant prostate cancer (CRPC) by exploring the proteome analysis.

2017 ◽  
Vol 35 (6_suppl) ◽  
pp. 247-247 ◽  
Author(s):  
Hiroji Uemura ◽  
Noriaki Arakawa ◽  
Yusuke Itoh ◽  
Takashi Kawahara ◽  
Yasuhide Miyoshi ◽  
...  

247 Background: It is well known that prostate specific antigen (PSA) level has no reliable correlation with pathological malignancy of prostate cancer and is not a predictor for the development of castration resistant prostate cancer (CRPC). The aim of this study is to explore novel biomarkers to predict the development of CRPC by using proteomics from secreted proteins from human prostate cancer cells. Methods: The proteins secreted from 6 prostate cancers in culture medium were analyzed and compared with 8 other cancer cells including renal and urothelial cancers using LTQ Orbitrap mass spectrometer. With the focus on high tissue specificity, the candidate biomarker proteins were then identified through analysis of gene expressions in proteins common to human prostate cancers by real time qPCR. Next, a system to measure the identified mouse monoclonal antibodies against the focused proteins was established. Finally, serum levels of these proteins from 33 patients with benign prostate hyperplasia (BPH), 31 with untreated prostate cancer (PCa) and 35 with CRPC, were measured. Results: The proteome analysis identified 12 candidates of secreted cell membrane proteins as new biomarkers. The proteome analysis indicated that not only matured GDF15, but pro-peptide as well as fragments (GDDP) are released from prostate cancer cells. Patients’ serum was analyzed for matured and pro-peptide GDF15 using ELISA and immunoprecipitation-MRM mass spectrometry. The results showed that the serum level of GDDP-1, one of the processing forms of GDDP, was significantly higher in CRPC than those in BPH and untreated PCa (P < 0.01). ROC analysis also showed that the AUC of GDDP-1(0.86) was higher than that of matured GDF15 (0.76). When the cutoff value of GDDP-1 was set at 4.0 ng/mL, there was a significant difference of overall survival (OS) in CRPC patients between those with more than 4.0 ng/mL compared to less than 4.0 ng/mL of GDDP-1, whereas there was no significant difference of OS measurable by PSA in CRPC patients. These data suggest that GDDP-1 may be a novel biomarker for CRPC. Conclusions: GDDP-1 shows potential as a novel biomarker for CRPC.

2011 ◽  
Vol 29 (7_suppl) ◽  
pp. 17-17
Author(s):  
Z. Liao ◽  
L. Gu ◽  
F. Shen ◽  
A. Dagvadorj ◽  
S. Gupta ◽  
...  

17 Background: There are no effective treatments for metastatic or castration resistant prostate cancer. We have shown that transcription factor Stat5a/b is constitutively active in high-grade prostate cancer, but not in normal human prostate epithelium. Stat5a/b is active in 95% of clinical castration resistant prostate cancers, and the expression of active Stat5a/b in primary prostate cancer predicts early disease recurrence. Stat5a/b is critical for the viability of prostate cancer cells in vitro and for growth of prostate xenograft tumors in nude mice. Stat5a/b synergizes with androgen receptor (AR) and Stat5a/b promotes metastatic behavior of human prostate cancer cells in vitro and in vivo. Here, we hypothesize that Stat5a/b is a molecular target for rational drug design for prostate cancer. Methods: We identified a small- molecule inhibitor of Stat5a/b dimerization by structure-based virtual screen from a database of 30 million chemical structures. The efficacy of the Stat5a/b inhibitor was determined by reporter gene assays, dimerization by co-immunoprecipitations, nuclear translocation by cytochemistry and binding to DNA by EMSA. Cell viability was analyzed by MTT assay. Results: The novel Stat5a/b inhibitor IST5-002 inhibited transcriptional activity of Stat5a/b at IC50 of 1.5 μ M for Stat5a and 3.5 μ M for Stat5b, but not of Stat3 in prostate cancer cells. IST5-002 inhibited dimerization, nuclear translocation, and binding of Stat5a/b to the Stat5 DNA consensus sequence. Furthermore, IST5-002 inhibited expression of Stat5a/b target gene cyclin D1, and induced massive apoptosis of DU145, CWR22Rv1 and LNCaP human prostate cancer cells. IST5-002 blocked prostate cancer xenograft tumor growth in nude mice and induced death in clinical prostate cancers ex vivo in 3D organ cultures. Conclusions: We have identified a small molecule Stat5a/b inhibitor IST5-002 for therapy development for prostate cancer. Future work will focus on chemical modifications of IST5-002 to achieve IC50 below 1 μ M and oral administration. No significant financial relationships to disclose.


2021 ◽  
Vol 11 ◽  
Author(s):  
I Gusti Md Gde Surya C. Trapika ◽  
Xin Tracy Liu ◽  
Long Hoa Chung ◽  
Felcia Lai ◽  
Chanlu Xie ◽  
...  

Prostate cancer is the second most prevalent malignancy worldwide. In the early stages, the development of prostate cancer is dependent on androgens. Over time with androgen deprivation therapy, 20% of prostate cancers progress to a castration-resistant form. Novel treatments for prostate cancers are still urgently needed. Erianin is a plant-derived bibenzyl compound. We report herein that erianin exhibits anti-tumor effects in androgen-sensitive and castration-resistant prostate cancer cells through different mechanisms. Erianin induces endoplasmic reticulum stress-associated apoptosis in androgen-sensitive prostate cancer cells. It also triggers pro-survival autophagic responses, as inhibition of autophagy predisposes to apoptosis. In contrast, erianin fails to induce apoptosis in castration-resistant prostate cancer cells. Instead, it results in cell cycle arrest at the M phase. Mechanistically, C16 ceramide dictates differential responses of androgen-sensitive and castration-resistant prostate cancer cells to erianin. Erianin elevates C16 ceramide level in androgen-sensitive but not castration-resistant prostate cancer cells. Overexpression of ceramide synthase 5 that specifically produces C16 ceramide enables erianin to induce apoptosis in castration-resistant prostate cancer cells. Our study provides both experimental evidence and mechanistic data showing that erianin is a potential treatment option for prostate cancers.


Cancers ◽  
2019 ◽  
Vol 11 (7) ◽  
pp. 945 ◽  
Author(s):  
Luna Laera ◽  
Nicoletta Guaragnella ◽  
Sergio Giannattasio ◽  
Loredana Moro

Background: Mutations in the oncosuppressor gene BReast CAncer susceptibility gene 2 (BRCA2) predispose to aggressive forms of prostate cancer which show poor response to taxane-based therapy, the standard treatment for castration-resistant, aggressive prostate cancer. Herein, we addressed the question whether changes in BRCA2 expression, a potential surrogate marker for BRCA2 activity, may affect the response of castration-resistant prostate cancer cells to 6-thioguanine (6-TG), a thiopurine used in the treatment of haematological malignancies. Methods: Yeast, normal prostate cells and castration-resistant prostate cancer cells were treated with 6-TG or its analogues, in presence or absence of paclitaxel, or with olaparib, a poly-(ADP-ribose) polymerase (PARP) inhibitor currently in clinical trials for treatment of metastatic castration-resistant prostate cancer, and cell proliferation, apoptosis and androgen receptor (AR) levels were measured. Results: 6-TG inhibited cell proliferation in yeast, normal and castration-resistant prostate cancer cells but promoted apoptosis only in cancer cells. Suppression of BRCA2 expression by siRNA or shRNA increased the sensitivity to 6-TG- and olaparib-induced apoptosis but did not affect cancer cell response to taxane. Intriguingly, 6-TG reduced AR expression levels independently on BRCA2 expression. Instead, olaparib decreased AR levels only in BRCA2-knockdown prostate cancer cells. Notably, overexpression of BRCA2 resulted in resistance of castration-resistant prostate cancer cells to 6-TG-, taxane- and olaparib-based treatment but promoted sensitivity to apoptosis induced by 2-amino-6-bromopurine and 2,6–dithiopurine, two 6-TG analogues. Conclusions: Our results provide a pre-clinical rationale for the use of 6-TG in the treatment of BRCA2-deficient castration-resistant prostate cancers, and of certain 6-TG analogues for treatment of BRCA2-proficient prostate cancers.


2010 ◽  
Vol 33 (2) ◽  
pp. 55-59 ◽  
Author(s):  
Lei Gu ◽  
Xian-Hua Zhu ◽  
Tapio Visakorpi ◽  
Kalle Alanen ◽  
Tuomas Mirtti ◽  
...  

Background: Transcription factor Stat5a/b is highly critical for the viability of human prostate cancer cells in vitro and for prostate tumor growthin vivo. Stat5 is constitutively active in clinical prostate cancers but not in the normal human prostate epithelium. Moreover, Stat5a/b activation in prostate cancer is associated with high histological grade of prostate cancer. However, the molecular mechanisms underlying constitutive activation of Stat5a/b in prostate cancer are unclear. The receptor-associated tyrosine kinase Jak2 is a known key activator of Stat5a/b in prostate cancer cells in response to ligand stimulation. Recently, a single gain-of-function point mutation ofJAK2was described in myeloproliferative diseases leading to constitutive Jak2 kinase activity, subsequent Stat5a/b activation and involvement of V617F Jak2 in the pathogenesis of myeloproliferative disorders.Materials and Methods: We determined whetherJAK2undergoes the V617F activating mutation during clinical progression of human prostate cancer using a highly sensitive assay (amplification refractory mutation system) and a unique material of fresh specimens from organ-confined or castration-resistant prostate cancers.Results: TheJAK2V617F mutation was not found in any of the normal or malignant prostate samples analyzed in this study.Conclusions: Future work should focus on determining the molecular mechanisms other than V617F mutation of Jak2 resulting in continuous Stat5 activation in clinical prostate cancers.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Ding-fang Zhang ◽  
Zhi-chun Yang ◽  
Jian-qiang Chen ◽  
Xiang-xiang Jin ◽  
Yin-da Qiu ◽  
...  

Abstract Background Metastatic castration-resistant prostate cancer (CRPC) is the leading cause of death among men diagnosed with prostate cancer. Piperlongumine (PL) is a novel potential anticancer agent that has been demonstrated to exhibit anticancer efficacy against prostate cancer cells. However, the effects of PL on DNA damage and repair against CRPC have remained unclear. The aim of this study was to further explore the anticancer activity and mechanisms of action of PL against CRPC in terms of DNA damage and repair processes. Methods The effect of PL on CRPC was evaluated by MTT assay, long-term cell proliferation, reactive oxygen species assay, western blot assay, flow cytometry assay (annexin V/PI staining), β-gal staining assay and DAPI staining assay. The capacity of PL to inhibit the invasion and migration of CRPC cells was assessed by scratch-wound assay, cell adhesion assay, transwell assay and immunofluorescence (IF) assay. The effect of PL on DNA damage and repair was determined via IF assay and comet assay. Results The results showed that PL exhibited stronger anticancer activity against CRPC compared to that of taxol, cisplatin (DDP), doxorubicin (Dox), or 5-Fluorouracil (5-FU), with fewer side effects in normal cells. Importantly, PL treatment significantly decreased cell adhesion to the extracellular matrix and inhibited the migration of CRPC cells through affecting the expression and distribution of focal adhesion kinase (FAK), leading to concentration-dependent inhibition of CRPC cell proliferation and concomitantly increased cell death. Moreover, PL treatment triggered persistent DNA damage and provoked strong DNA damage responses in CRPC cells. Conclusion Collectively, our findings demonstrate that PL potently inhibited proliferation, migration, and invasion of CRPC cells and that these potent anticancer effects were potentially achieved via triggering persistent DNA damage in CRPC cells.


Endocrinology ◽  
2015 ◽  
Vol 156 (1) ◽  
pp. 58-70 ◽  
Author(s):  
Ryuta Tanimoto ◽  
Alaide Morcavallo ◽  
Mario Terracciano ◽  
Shi-Qiong Xu ◽  
Manuela Stefanello ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document