Ovarian Function Preservation in Patients With Cervical Cancer Undergoing Hysterectomy and Ovarian Transposition Before Pelvic Radiotherapy.

To examine the factors associated with ovarian failure (OF) and assess the effectiveness of ovarian transposition (OT) before pelvic irradiation for preserving ovarian function in patients with cervical cancer (CC) undergoing hysterectomy. During 2003 to 2017, patients who underwent hysterectomy with preservation of one or both ovaries were retrospectively enrolled. Patients were divided into 4 groups, depending on whether radiotherapy (RT) and OT were performed: group 1, RT(+) and OT(+); group 2, RT(+) and OT(-); group 3, RT(-) and OT(+); group 4, RT(-) and OT(-). OF was defined as serum follicle-stimulating hormone levels of ≥30 mIU/mL. Sixty-six patients (59 [89.4%] invasive CC and 7 [10.6%] cervical intraepithelial neoplasia) were included. The 2-year OF-free survival rate was 61.4% (95% confidence interval [CI] 37.8-86.0), 0%, 91.7% (95% CI 76.0-100), and 75.8% (95% CI 58.2-93.4) for groups 1, 2, 3, and 4, respectively. In groups 1 and 2 receiving RT, OT, and combination of external beam radiotherapy and vaginal brachytherapy were associated with OF on multivariate analysis (MVA) (P-value = .002 and .046, respectively). In groups 3 and 4 without RT, older age (40 years old) and OT did not affect OF; however, the number of remaining ovaries was independently associated with OF in MVA (P = .035). OT could effectively preserve ovarian function in patients treated with adjuvant RT, while OT procedure itself did not affect ovarian failure. OT should be considered in the management of premenopausal cervical cancer patients.

SIRT1 attenuates PAF-induced MMP-2 production via down-regulation of PAF receptor expression in vascular smooth muscle cells.

Silent mating type information regulation 2 homolog 1 (SIRT1) is known as a key regulator in the protection of various vascular disorders, however, no direct evidences have been reported in the progression of atherosclerosis. Considering the pivotal role of matrix metalloproteinase-2 (MMP-2) in plaque destabilization, this study investigated the role of SIRT1 on MMP-2 production in vascular smooth muscle cells (VSMCs) induced by platelet activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine). In VSMCs stimulated with resveratrol, SIRT1 activator, PAF receptor (PAFR) was internalized and then its protein levels were diminished. It was attenuated in cells pretreated with proteasome or lysosome inhibitor. Also, the degradation of PAFR in SIRT1-stimulated cells was significantly attenuated by ß-arrestin2 depletion. In cells treated with nicotinamide, SIRT1 deacetylase inhibitor, PAFR internalization by resveratrol or reSIRT1 was inhibited, demonstrating that deacetylation of SIRT1 is an important step in SIRT1-induced PAFR down-regulation. Moreover, PAF-induced MMP-2 production in VSMCs and aorta was attenuated by resveratrol. In the aorta of SIRT1 transgenic mice, the PAF-induced MMP-2 expression was prominently attenuated compared to that in wild type mice. Taken together, it was suggested that SIRT1 down-regulated PAFR in VSMCs via ß-arrestin2-mediated internalization and degradation, leading to an inhibition of PAF-induced MMP-2 production.

PAF enhances MMP-2 production in rat aortic VSMCs via a ß-arrestin2-dependent ERK signaling pathway.

Platelet-activating factor (PAF), 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine, is a potent phospholipid mediator and has been reported to be localized in atherosclerotic plaque. However, its role in the progression of atherosclerosis remains unclear. In the present study, we investigated the role of PAF in the production of matrix metalloproteinase (MMP) in primary vascular smooth muscle cells (VSMCs). When rat aortic primary VSMCs were stimulated with PAF (1 nmol/l), the expressions of MMP-2 mRNA and protein, but not of MMP-9, were significantly increased, and these upregulations were markedly attenuated by inhibiting extracellular signal-regulated kinases (ERKs) using molecular and pharmacological inhibitors, but not by using inhibitors of p38 mitogen-activated protein kinase or c-Jun N-terminal kinase. Likewise, ERK phosphorylation was markedly enhanced in PAF-stimulated VSMCs, and this was attenuated by WEB2086, but not by EGF receptor inhibitor, demonstrating the specificity of PAF receptor (PAFR) in PAF-induced ERK phosphorylation. In immunofluorescence studies, ß-arrestin2 in PAF-stimulated VSMCs colocalized with PAFR and phosphorylated ERK (P-ERK). Coimmunoprecipitation results suggest that ß-arrestin2-bound PAFRs existed as a complex with P-ERK. In addition, PAF-induced ERK phosphorylation and MMP-2 production were significantly attenuated by ß-arrestin2 depletion. Taken together, the study shows that PAF enhances MMP-2 production in VSMCs via a ß-arrestin2-dependent ERK signaling pathway.

Cyclosporin A and sanglifehrin A enhance chemotherapeutic effect of cisplatin in C6 glioma cells.

Glioma is the most common type of brain tumors in adults, and treatment of high-grade gliomas is still palliative. Studies to date have revealed only modest effect in attenuating growth of these tumors with single agent therapy, but combination treatment appears to be more effective. Cyclophilin A (CypA), a target of immunosuppressive drugs cyclosporin A (CsA) and sanglifehrin A (SFA), is an intracellular protein that has peptidyl-prolyl cis-trans isomerase (PPIase) enzymatic activity. Previously, we showed that overexpressed CypA induced chemoresistance in cancer cells. Here we provide evidence that combination of cisplatin with either CsA or SFA synergistically enhances apoptotic cell death in C6 glioma cells, compared with single agent treatment. Enhanced apoptotic cell death is a result of an increase in ROS generation and a decrease in intracellular glutathione levels. Consistently, CypA knockdown by siRNA also enhances cisplatin-induced apoptosis. Immunohistochemical analysis showed increased expression of CypA in human glioblastoma multiforme, but not in normal human astrocytes. CypA was also shown to be up-regulated in C6 glioma cells during hypoxia. In conclusion, CsA or SFA in combination with cisplatin synergistically enhances cisplatin-induced apoptosis in C6 glioma cells via inhibition of PPIase activity of CypA, indicating that development of new drugs that selectively inhibit the CypA PPIase activity without immune suppression may facilitate alleviation of chemoresistance in treatment of high-grade glioma.