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Inflammation contributes to pain hypersensitivity through multiple mechanisms. Among the most well characterized of these is the sensitization of primary nociceptive neurons by arachidonic acid metabolites such as prostaglandins through G protein-coupled receptors. However, in light of the recent discovery that the nociceptor-specific ion channel transient receptor potential A1 (TRPA1) can be activated by exogenous electrophilic irritants through direct covalent modification, we reasoned that electrophilic carbon-containing A-and J-series prostaglandins, metabolites of prostaglandins (PG) E 2 and D 2 , respectively, would excite nociceptive neurons through direct activation of TRPA1. Consistent with this prediction, the PGD 2 metabolite 15-deoxy-⌬ 12,14 -prostaglandin J 2 (15dPGJ 2 ) activated heterologously expressed human TRPA1 (hTRPA1-HEK), as well as a subset of chemosensitive mouse trigeminal neurons. The effects of 15dPGJ 2 on neurons were blocked by both the nonselective TRP channel blocker ruthenium red and the TRPA1 inhibitor (HC-030031), but unaffected by the TRPV1 blocker iodo-resiniferatoxin. In whole-cell patch-clamp studies on hTRPA1-HEK cells, 15dPGJ 2 evoked currents similar to equimolar allyl isothiocyanate (AITC) in the nominal absence of calcium, suggesting a direct mechanism of activation. Consistent with the hypothesis that TRPA1 activation required reactive electrophilic moieties, A-and J-series prostaglandins, and the isoprostane 8-iso-prostaglandin A 2 -evoked calcium influx in hTRPA1-HEK cells with similar potency and efficacy. It is noteworthy that this effect was not mimicked by their nonelectrophilic precursors, PGE 2 and PGD 2 , or PGB 2 , which differs from PGA 2 only in that its electrophilic carbon is rendered unreactive through steric hindrance. Taken together, these data suggest a novel mechanism through which reactive prostanoids may activate nociceptive neurons independent of prostaglandin receptors.Peripheral inflammation induces the formation of prostaglandins (PGs), both centrally and peripherally, which contribute to pain sensation and sensitivity (Woolf and Costigan, 1999;Burian and Geisslinger, 2005). During inflammation, a superfamily of phospholipase A 2 enzymes hydrolyzes membrane phospholipids to release arachidonic acid, which is subsequently converted by cyclooxygenases (COXs) into PGH 2 . Through the actions of tissue-specific isomerases, a variety of prostaglandins is formed from this intermediate; for example, PGE 2 , PGD 2 , and PGI 2 . The contribution of prostaglandins to inflammatory pain is extensively documented and is demonstrated by the analgesic properties of COX inhibitors (Burian and Geisslinger, 2005). Research has followed into the specific mechanisms and pathways through which prostaglandins contribute to inflammation and nociception and many prostaglandin receptors (including those for PGE 2 , PGD 2 , and PGI 2 ) have been demonstrated on sensory nerves (Jenkins et al., 2001;Moriyama et al., 2005).The nonselective cation channel transient ...

Background. Tisotumab vedotin (TV; HuMax-TF-ADC), is a first-in-class antibody-drug conjugate directed against tissue factor (TF), which is expressed across multiple solid tumor types and is associated with poor clinical outcomes. We hypothesize that TV could have antitumor activity in tumors known to express TF. Methods. This is a phase 1/2 open-label, dose-escalation and-expansion study (innovaTV201; NCT02001623) evaluating the safety, tolerability, pharmacokinetics (PK) profile, and antitumor activity of TV in patients with locally advanced and/or metastatic solid tumors known to express TF. In the dose-escalation phase, patients were treated with TV intravenously once every 3 weeks in a traditional 3 + 3 design to determine the maximum-tolerated dose (MTD) and recommended phase 2 dose (RP2D). Plasma was collected to characterize the PK profile of TV. In the dose-expansion phase, patients are treated at the RP2D in seven advanced solid tumor-type cohorts, including bladder, cervix, endometrium, esophagus, lung, ovary, and prostate cancers. Findings. In the dose-escalation phase, 27 patients with advanced solid tumors received TV in eight sequential dose cohorts between 0•3 and 2•2 mg/kg. Dose-limiting toxicities, including grade 3 type 2 diabetes mellitus, mucositis, and neutropenic fever, were observed at TV 2•2 mg/kg. TV at 2•0 mg/kg was identified as the MTD and the RP2D. The PK profile of TV was dose proportional. In the dose-expansion phase, 147 patients with solid tumors were treated with TV at 2•0 mg/kg. The most common (≥20%) treatment-emergent adverse events (AEs) of any grade included epistaxis, fatigue, nausea, alopecia, conjunctivitis, decreased appetite, and constipation. Across tumor

Transient Receptor Potential A1 (TRPA1) is a nonselective cation channel, preferentially expressed on a subset of nociceptive sensory neurons, that is activated by a variety of reactive irritants via the covalent modification of cysteine residues. Excessive nitric oxide during inflammation (nitrative stress), leads to the nitration of phospholipids, resulting in the formation of highly reactive cysteine modifying agents, such as nitrooleic acid (9-OA-NO 2 ). Using calcium imaging and electrophysiology, we have shown that 9-OA-NO 2 activates human TRPA1 channels (EC 50 , 1 M), whereas oleic acid had no effect on TRPA1. 9-OA-NO 2 failed to activate TRPA1 in which the cysteines at positions 619, 639, and 663 and the lysine at 708 had been mutated. TRPA1 activation by 9-OA-NO 2 was not inhibited by the NO scavenger carboxy-PTIO. 9-OA-NO 2 had no effect on another nociceptive-specific ion channel, TRPV1. 9-OA-NO 2 activated a subset of mouse vagal and trigeminal sensory neurons, which also responded to the TRPA1 agonist allyl isothiocyanate and the TRPV1 agonist capsaicin. 9-OA-NO 2 failed to activate neurons derived from TRPA1(Ϫ/Ϫ) mice. The action of 9-OA-NO 2 at nociceptive nerve terminals was investigated using an ex vivo extracellular recording preparation of individual bronchopulmonary C fibers in the mouse. 9-OA-NO 2 evoked robust action potential discharge from capsaicin-sensitive fibers with slow conduction velocities (0.4 -0.7 m/s), which was inhibited by the TRPA1 antagonist AP-18. These data demonstrate that nitrooleic acid, a product of nitrative stress, can induce substantial nociceptive nerve activation through the selective and direct activation of TRPA1 channels.Oxidative stress and nitrative stress have been implicated as contributing to acute and chronic inflammation (Radi, 2004;Szabó et al., 2007;Valko et al., 2007). Nitric oxide (NO) is an endogenous mediator with multiple cellular functions that is produced by many cell types including vascular endothelium, neutrophils, fibroblasts, and nerves (Bian and Murad, 2003). NO, generated from L-arginine by NO synthases (NOS), reacts with the reactive oxygen species (ROS) superoxide-which is formed through multiple pathways in inflammation, including NADPH oxidase, xanthine oxidase, and perverted mitochondrial function-to produce the reactive nitrogen species (RNS), peroxynitrite (ONOOϪ), and nitrogen dioxide (*NO 2 ). RNS are potent inflammatory molecules that can react with lipids, proteins, and DNA (Szabó et al., 2007). Within membranes, where the hydrophobic environment maximizes RNS production (Möller et al., 2007), RNS react with unsaturated fatty acids (e.g., oleic acid), causing the addition of an NO 2 group (nitration) Jain et al., 2008;Trostchansky and Rubbo, 2008). Nitrated fatty acids (e.g., nitrooleic acid) are highly reactive electrophilic compounds that can modulate a variety of cellular targets, including thiol residues and peroxisome proliferator-activated receptor ␥ Trostchansky and Rubbo, 2008 ABBREVIATIONS: NOS, nitric-oxide ...

◥Purpose: Tissue factor (TF) is a potential target in cervical cancer, as it is frequently highly expressed and associated with poor prognosis. Tisotumab vedotin, a first-in-class investigational antibody-drug conjugate targeting TF, has demonstrated encouraging activity in solid tumors. Here we report data from the cervical cancer cohort of innovaTV 201 phase I/II study (NCT02001623).Patients and Methods: Patients with recurrent or metastatic cervical cancer received tisotumab vedotin 2.0 mg/kg every 3 weeks until progressive disease, unacceptable toxicity, or consent withdrawal. The primary objective was safety and tolerability. Secondary objectives included antitumor activity.Results: Of the 55 patients, 51% had received !2 prior lines of treatment in the recurrent or metastatic setting; 67% had prior bevacizumab þ doublet chemotherapy. Fifty-one percent of patients had squamous cell carcinoma. The most common grade 3/4 treatment-emergent adverse events (AEs) were anemia (11%), fatigue (9%), and vomiting (7%). No grade 5 treatment-related AEs occurred. Investigator-assessed confirmed objective response rate (ORR) was 24% [95% confidence interval (CI): 13%À37%]. Median duration of response (DOR) was 4.2 months (range: 1.0 þ À9.7); four patients responded for >8 months. The 6-month progression-free survival (PFS) rate was 29% (95% CI: 17%À43%). Independent review outcomes were comparable, with confirmed ORR of 22% (95% CI: 12%À35%), median DOR of 6.0 months (range: 1.0 þ À9.7), and 6-month PFS rate of 40% (95% CI: 24%À55%). Tissue factor expression was confirmed in most patients; no significant association with response was observed.Conclusions: Tisotumab vedotin demonstrated a manageable safety profile and encouraging antitumor activity in patients with previously treated recurrent or metastatic cervical cancer.Cervical cancer is a common cancer in women, with an estimated 570,000 new cases globally in 2018, and represents the third leading cause of cancer-related death in women worldwide (1). Approximately 15,500 and 61,000 new cases of cervical cancer were estimated in North America and in Europe in 2018, respectively, resulting in approximately 5,800 and 25,800 deaths (2). Recurrent or metastatic cervical cancer has a poor prognosis, with a 5-year survival rate of 17% (3). Bevacizumab and doublet chemotherapy (paclitaxel and cisplatin or paclitaxel and topotecan) were adopted as first-line (1L) standard-ofcare therapy for recurrent or metastatic cervical cancer in the past 5 years (4-6). However, nearly all patients relapse after 1L treatment, and single-institution experiences indicate that the percentage of patients who receive a second-line (2L) therapy varies (30%-70%) as many patients die before receiving treatment (7,8).Available 2Lþ therapies for recurrent or metastatic cervical cancer are characterized by low response rates (5,6). Before adoption of bevacizumab plus doublet chemotherapy in 1L, therapies administered in the 2Lþ setting reported response rates in the range of 4.5% to 15%, with median s...