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CRISPR/Cas gene studies were conducted in HeLa cells where either PGRMC1, TMEM97 or both proteins were removed via gene editing. A series of radioligand binding studies, confocal microscopy studies, and internalization of radiolabeled or fluorescently tagged LDL particles were then conducted in these cells. The results indicate that PGRMC1 knockout (KO) did not reduce the density of binding sites for the sigma-2 receptor (σ2R) radioligands, [125I]RHM-4 or [3H]DTG, but a reduction in the receptor affinity of both radioligands was observed. TMEM97 KO resulted in a complete loss of binding of [125I]RHM-4 and a significant reduction in binding of [3H]DTG. TMEM97 KO and PGRMC1 KO resulted in an equal reduction in the rate of uptake of fluorescently-tagged or 3H-labeled LDL, and knocking out both proteins did not result in a further rate of reduction of LDL uptake. Confocal microscopy and Proximity Ligation Assay studies indicated a clear co-localization of LDLR, PGRMC1 and TMEM97. These data indicate that the formation of a ternary complex of LDLR-PGRMC1-TMEM97 is necessary for the rapid internalization of LDL by LDLR.

In China, the social risks associated with housing demolition increasingly present a challenge to the success of urban redevelopment projects. In practice, these risks are interacting and are associated with various stakeholders. Previous studies have largely focused on what the risks are and how they affect redevelopment projects without giving sufficient consideration to key stakeholders and their linkages with risks. Therefore, we sought to use social network analysis to investigate social risks related to housing demolition, based on a stakeholder perspective. Stakeholder-associated risks and their interrelations were identified and subsequently quantified based on a literature analysis and interviews with key stakeholders. Using a network analysis we identified critical risks and their corresponding stakeholders. Social security schemes, efficient financial management, multi-dimensional impact assessments, policy analyses and adherence to laws, as well as public participation were proposed to mitigate social risks during housing demolition. The This is the Pre-Published Version.

50% of patients with HRD respond to PARPi therapy (3). Moreover, patients without known HRD have also shown a clinical benefit from PARPis, as seen in recent trials assessing niraparib, olaparib, or rucaparib, as maintenance therapy in platinum-sensitive recurrent ovarian cancer (5-8). Given that not all patients will respond to PARPi therapy, improved clinical tools for predicting which patients will respond are urgently needed.Numerous clinical trials have led to FDA approval of 3 PARPis since 2014 and there is continued development of 2 additional drugs within this class (9-13). Despite growth in the BACKGROUND. Poly(ADP-ribose) polymerase (PARP) inhibitors are effective in a broad population of patients with ovarian cancer; however, resistance caused by low enzyme expression of the drug target PARP-1 remains to be clinically evaluated in this context. We hypothesize that PARP-1 expression is variable in ovarian cancer and can be quantified in primary and metastatic disease using a novel PET imaging agent. METHODS.We used a translational approach to describe the significance of PET imaging of PARP-1 in ovarian cancer. First, we produced PARP1-KO ovarian cancer cell lines using CRISPR/Cas9 gene editing to test the loss of PARP-1 as a resistance mechanism to all clinically used PARP inhibitors. Next, we performed preclinical microPET imaging studies using ovarian cancer patient-derived xenografts in mouse models. Finally, in a phase I PET imaging clinical trial we explored PET imaging as a regional marker of PARP-1 expression in primary and metastatic disease through correlative tissue histology. RESULTS.We found that deletion of PARP1 causes resistance to all PARP inhibitors in vitro, and microPET imaging provides proof of concept as an approach to quantify PARP-1 in vivo. Clinically, we observed a spectrum of standard uptake values (SUVs) ranging from 2-12 for PARP-1 in tumors. In addition, we found a positive correlation between PET SUVs and fluorescent immunohistochemistry for PARP-1 (r 2 = 0.60).CONCLUSION. This work confirms the translational potential of a PARP-1 PET imaging agent and supports future clinical trials to test PARP-1 expression as a method to stratify patients for PARP inhibitor therapy.TRIAL REGISTRATION. Clinicaltrials.gov NCT02637934. 22-24). Furthermore, PARP-1 has been development and application of PARPis, the primary drug target poly(ADP-ribose) polymerase 1 (PARP-1) has never been evaluated in vivo, even though loss of expression in vitro is a wellcharacterized resistance mechanism (3,(14)(15)(16)(17)(18)(19). It was first hypothesized that PARPis work primarily through a synthetic lethality pathway where loss of BRCA1 or BRCA2 combined with chemical inhibition of PARP-1 results in cell death (20, 21). However, it was later shown that deletion of PARP1 did not result in BRCA1-restored cells showed no increase in γH2AX compared with DMSO controls. Olaparib-treated OVCAR8 PARP1-KO G1 and G3 cells showed a 1.3 times increase (ANOVA, **P < 0.01 and ***P < 0.001, respectively) in γH2AX...

Reactive oxygen species (ROS) are believed to play a major role in the proinflammatory, M1-polarized form of neuroinflammation. However, it has been difficult to assess the role of ROS and their role in neuroinflammation in animal models of disease because of the absence of probes capable of measuring their presence with the functional imaging technique positron emission tomography (PET). This study describes the synthesis and in vivo evaluation of [18F]ROStrace, a radiotracer for imaging superoxide in vivo with PET, in an LPS model of neuroinflammation. [18F]ROStrace was found to rapidly cross the blood–brain barrier (BBB) and was trapped in the brain of LPS-treated animals but not the control group. [18F]ox-ROStrace, the oxidized form of [18F]ROStrace, did not cross the BBB. These data suggest that [18F]ROStrace is a suitable radiotracer for imaging superoxide levels in the central nervous system with PET.