The association between childhood maltreatment and pain catastrophizing in individuals with immune-mediated inflammatory diseases.

OBJECTIVE: Childhood maltreatment is associated with pain catastrophizing. Both childhood maltreatment and pain catastrophizing are prevalent in certain immune-mediated inflammatory disease (IMID) populations. However, it is unknown whether childhood maltreatment contributes to the high rates of pain catastrophizing in IMID cohorts. We assessed the relationship between childhood maltreatment and pain catastrophizing in individuals with IMID, and whether this differed across IMID. METHODS: Between November 2014 and July 2016 we recruited individuals with multiple sclerosis (MS), inflammatory bowel disease (IBD), and rheumatoid arthritis (RA). Participants completed the Childhood Trauma Questionnaire-Short Form, the Pain Catastrophizing Scale, and Hospital Anxiety and Depression Scale. We tested the association between childhood maltreatment and pain catastrophizing using multivariable logistic regression. RESULTS: We included 577 individuals with IMID (MS: 232, IBD: 215, RA: 130). Overall, 265 (46%) participants with IMID reported any childhood maltreatment, with the most common type of maltreatment being emotional neglect. Childhood maltreatment was associated with pain catastrophizing (OR 3.32; 95% CI 1.89-5.85) independent of other risk factors, including sociodemographics and symptoms of anxiety and depression. CONCLUSION: Pain catastrophizing is highly prevalent in our IMID population, and strongly associated with childhood maltreatment in this population. Interventions that consider childhood maltreatment and pain catastrophizing should be incorporated into the clinical management of IMID patients.

Prolactin and androgen R1881 induce pro-survival carboxypeptidase-D and EDD E3 ligase in triple-negative and HER2+ breast cancer.

Plasma membrane carboxypeptidase-D (CPD) hydrolyzes C-terminal arginine (Arg) from extracellular substrates, and Arg is converted into nitric oxide (NO) in the cell. CPD is upregulated by prolactin (PRL) and androgens in breast cancer (BCa) cells, increasing NO production to promote cell survival. EDD E3 ubiquitin ligase, upregulated by PRL/androgens, is implicated in TORC1 signaling. This study investigated CPD and EDD in triple-negative (TNBC) and HER2+ BCa. Kaplan-Meier analysis showed a negative correlation between CPD or EDD mRNA expression in TNBC patients and relapse-free survival. Immunohistochemistry showed that benign and malignant breast tissues stained abundantly for the PRL receptor (PRLR) and androgen receptor (AR). CPD and EDD staining were elevated in TNBC and HER2+ tumors as compared to benign tissues. In TNBC/HER2+ cell lines, CPD and EDD protein expression were upregulated by PRL or synthetic androgen methyltrienolone (R1881) at 3-6 h. PRL/R1881-induced CPD in TNBC and HER2+ cells increased intracellular NO production, which was abolished by PRLR antagonist ∆1-9-G129R-hPRL and AR antagonist flutamide. In turn, treatment with NO increased viability and decreased apoptosis in Arg-deprived TNBC cells. Cell viability and apoptosis were also affected in HER2+ cells with CPD knockdown. Lastly, EDD knockdown decreased PRL/R1881-induced phosphorylation of initiation factor 4E binding protein-1 and decreased 4E release in TNBC cells. In summary, PRL/R1881-induced CPD promotes TNBC/HER2+ cell survival through production of NO, and EDD promotes TNBC cell survival by TORC1 activation. This study implicates CPD and EDD as useful therapeutic targets for TNBC/HER2+ tumors, and suggests that PRLR and AR blockade are also beneficial to these patients.

Prolactin-inducible EDD E3 ubiquitin ligase promotes TORC1 signalling, anti-apoptotic protein expression, and drug resistance in breast cancer cells.

Previously, we identified a prolactin (PRL)-inducible gene encoding EDD E3 ubiquitin ligase in human breast cancer (BCa) cells. We reported that EDD binds the mTOR (TORC1)-associated α4 phosphoprotein-PP2Ac protein phosphatase complex that regulates initiation of translation and cell cycle progression, and that EDD targets PP2Ac for proteasomal degradation. The present study showed that EDD immunostaining was low in benign human breast tissues, but increased progressively in ductal carcinoma in-situ, low-grade, and high-grade BCa, and in triple-negative BCa (TNBC). EDD mRNA and protein levels varied in human BCa cell lines. In high-EDD expressing MCF-7 and T47D cells, siRNA knockdown of EDD arrested cells in the G2-phase of the cell cycle, decreased cell viability, and increased apoptosis. EDD siRNA-induced apoptosis in MCF-7 cells correlated with significantly increased levels of pro-apoptotic Bim and Bak mRNAs and proteins (P < 0.05, n = 3-6), and increased levels of pro-apoptotic Bax and MOAP-1 proteins (P < 0.001, n = 3-6), leading to increased cleavage of caspase-7 and caspase substrate poly-ADP-ribose polymerase-1 (PARP-1), as compared to control cells. Loss of EDD in MCF-7 cells decreased PRL-induced phosphorylation of eukaryotic initiation factor 4E-binding protein-1, a mediator of TORC1 signaling, resulting in decreased binding of 4E to γ-aminophenyl-m7GTP agarose in Cap-binding assays. In low-EDD expressing MDA-MB-436 TNBC cell line, gain of EDD following pCMV-Tag2B.EDD transfection increased cell resistance to chemotherapeutic drugs cisplatin and doxorubicin, TORC1 inhibitor rapamycin, and TORC1/TORC2 inhibitor INK128, as compared to controls. In contrast, loss of EDD in MCF-7 cells increased cell sensitivity to cisplatin, doxorubicin, rapamycin, and selective estrogen receptor modulator tamoxifen. In summary, EDD levels increase with BCa progression in vivo. PRL-inducible EDD in BCa cells promotes TORC1 signaling, anti-apoptotic protein expression, and drug resistance in vitro. These findings implicate EDD as a potential therapeutic target and support PRL receptor blockade as an additional therapy for BCa.