Limited Significance of Activated Akt-Mammalian Target of Rapamycin Signaling Pathway in Prostate Cancer Progression

Abstract

Objective: The objective of this study was to investigate the significance of the activated Akt-mammalian target of rapamycin (Akt-mTOR) signaling pathway in the progression of prostate cancer. Materials and Methods: The expression levels of Akt, phosphorylated Akt (p-Akt), mTOR and phosphorylated mTOR (p-mTOR) in 175 prostate specimens, including 61 normal prostate tissues as a control, 24 high-grade prostatic intraepithelial neoplasias (HGPINs) and 90 clinically localized prostate cancers, were evaluated by immunohistochemical staining. p-Akt and p-mTOR ratios, which were defined as the expression level of p-Akt in relation to that of Akt and the expression level of p-mTOR in relation to that of mTOR, respectively, in these specimens were calculated. Results: Expression levels of all four molecules, including Akt, p-Akt, mTOR and p-mTOR, were significantly greater in the HGPIN group compared with the normal control and prostate cancer groups. Furthermore, the p-Akt ratio in the prostate cancer group was significantly lower than that in the HGPIN group, while there was no significant difference in the p-mTOR ratio between the HGPIN and prostate cancer groups. In the prostate cancer group, no significant relationships were observed between major clinicopathological parameters and the expression levels as well as the ratios of p-Akt or p-mTOR. Conclusions: The Akt-mTOR signaling pathway may play a limited role in the progression of prostate cancer.

AMD3100 inhibits epithelial–mesenchymal transition, cell invasion, and metastasis in the liver and the lung through blocking the SDF‐1α/CXCR4 signaling pathway in prostate cancer

“…Recently, the Akt-mammalian target of rapamycin and the Hedgehog signaling pathways have been implicated in the development and progression of PC (Ko, Miyake, Behnsawy, Cheon, & Fujisawa, 2014, Slusarz et al, 2010. In this study, we demonstrate that AMD3100…”

“…PC is one of the most common malignant tumors in men with increasing incidence and mortality rates in China (Ye & Zhu, ). Recently, the Akt‐mammalian target of rapamycin and the Hedgehog signaling pathways have been implicated in the development and progression of PC (Ko, Miyake, Behnsawy, Cheon, & Fujisawa, , Slusarz et al, ). In this study, we demonstrate that AMD3100 inhibits EMT and metastasis of PC cells by blocking the SDF‐1α/CXCR4 signaling pathway.…”

Intratumoral Heterogeneity Determines the Expression of mTOR-pathway Proteins in Prostate Cancer

“…In the meta-analysis, 4 studies [14, 16–18] with 736 patients with PCa were identified as eligible for the forest plot after the evaluation of the association between immunostaining and BCR.…”

XAGE-1b Cancer/Testis Antigen Is a Potential Target for Immunotherapy in Prostate Cancer

“…Furthermore, because of their very restricted normal tissue expression, immunotherapy targeting CTAs is expected to be more specific and less toxic. Like other members of the CTA family such as MAGE, NY-ESO-1 and SSX2, XAGE-1 has been identified and shown to be expressed in various tumors [15,16,17]. Among the four transcript variants, XAGE-1a, XAGE-1b, XAGE-1c and XAGE-1d, XAGE-1b was identified as a dominant antigen recognized by serum from PCa patients.…”