How autophagy, an evolutionarily conserved intracellular catabolic system for bulk degradation, selectively degrades protein aggregates is poorly understood. Here, we show that several maternally derived germ P granule components are selectively eliminated by autophagy in somatic cells during C. elegans embryogenesis. The activity of sepa-1 is required for the degradation of these P granule components and for their accumulation into aggregates, termed PGL granules, in autophagy mutants. SEPA-1 forms protein aggregates and is also a preferential target of autophagy. SEPA-1 directly binds to the P granule component PGL-3 and also to the autophagy protein LGG-1/Atg8. SEPA-1 aggregates consistently colocalize with PGL granules and with LGG-1 puncta. Thus, SEPA-1 functions as a bridging molecule in mediating the specific recognition and degradation of P granule components by autophagy. Our study reveals a mechanism for preferential degradation of protein aggregates by autophagy and emphasizes the physiological significance of selective autophagy during animal development.

Purpose: The aims were to assess the safety, pharmacokinetics, maximum tolerated dose, and antitumor activity of AMG 102, a fully human hepatocyte growth factor/scatter factor (HGF/SF)-neutralizing monoclonal antibody, in patients with solid tumors.Experimental Design: Patients (N = 40) with refractory advanced solid tumors were enrolled into six sequential dose-escalation cohorts (0.5, 1, 3, 5, 10, or 20 mg/kg AMG 102 i.v. every 2 weeks) and a doseexpansion cohort (20 mg/kg AMG 102 every 2 weeks). Safety, anti-AMG 102 antibody formation, pharmacokinetics, tumor response, and exploratory biomarkers were assessed.Results: AMG 102 was well tolerated up to the planned maximum dose of 20 mg/kg, and the maximum tolerated dose was not reached. Treatment-related adverse events were generally mild and included fatigue (13%), constipation (8%), nausea (8%), vomiting (5%), anorexia (5%), myalgia (5%), and hypertension (5%). Two patients experienced dose-limiting toxicities: one patient (0.5 mg/kg cohort) experienced grade 3 hypoxia and grade 3 dyspnea and one patient (1 mg/kg cohort) experienced grade 3 upper gastrointestinal hemorrhage. No anti-AMG 102 antibodies were detected, and AMG 102 had linear pharmacokinetics within the dose range investigated. Sixteen of 23 (70%) evaluable patients had a best response of stable disease with progression-free survival ranging from 7.9 to 40 weeks. Circulating levels of the biomarker HGF/SF (bound and unbound) increased in a dose-dependent manner, whereas soluble c-Met concentrations were generally similar across doses.Conclusions: AMG 102 is safe and well tolerated, has a favorable pharmacokinetic profile, and will be further investigated as a monotherapy and in combination with other agents.

High-grade serous ovarian cancer (HGS-OvCA) is an aggressive form of epithelial ovarian cancer (EOC), and accounts for the majority of deaths due to EOC. The critical cellular processes and underlying molecular mechanisms that define this malignancy remain poorly understood. Using a syngeneic murine model, we investigated the changes that accompanied the progression to increased aggressiveness induced by in vivo passage of mouse EOC cells. We found that enhanced anoikis resistance was a key cellular process associated with greater aggressiveness and tumorigenicity in vivo. Biochemical studies revealed that the enhanced anoikis resistance was associated with the activation of the Src/Akt/Erk signaling pathway. A higher rate of metabolism and autophagy were also associated with increased anoikis resistance. Blocking these pathways with specific inhibitors and/or genetic modifications significantly increased anoikis in vitro and inhibited tumor development in vivo. In addition, we demonstrated that similar signaling pathways were also involved in a human EOC cell line model. Collectively, our data suggest that anoikis resistance represents a critical and a distinguishing feature underlying the aggressiveness of ovarian cancer cells.

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PurposeCapsaicin-induced dermal blood flow (CIDBF) is a validated biomarker used to evaluate the target engagement of potential calcitonin gene-related peptide-blocking therapeutics for migraine. To characterize the pharmacokinetics (PK) and quantify the inhibitory effects of erenumab (AMG 334) on CIDBF, CIDBF data were pooled from a single- and a multiple-dose study in healthy and migraine subjects.MethodsRepeated capsaicin challenges and DBF measurements were performed and serum erenumab concentrations determined. A population analysis was conducted using a nonlinear mixed-effects modeling approach. Effects of body weight, gender, and age on model parameters were evaluated.ResultsTwo-compartment target-mediated drug disposition (TMDD) model assuming binding of erenumab in the central compartment best described the nonlinear PK of erenumab. Subcutaneous absorption half-life was 1.6 days and bioavailability was 74%. Erenumab produced a maximum inhibition of 89% (95% confidence interval: 87–91%). Erenumab concentrations required for 50% and 99% of maximum inhibition were 255 ng/mL and 1134 ng/mL, respectively. Increased body weight was associated with increased erenumab clearance but had no effect on the inhibitory effect on CIDBF.ConclusionsOur results show that erenumab pharmacokinetics was best characterized by a TMDD model and resulted in potent inhibition of CIDBF.Electronic supplementary materialThe online version of this article (doi:10.1007/s11095-017-2183-6) contains supplementary material, which is available to authorized users.

Recently, hepatitis B core-related antigen (HBcrAg) has been suggested as an additional marker of hepatitis B virus (HBV) infection. This study aimed to investigate whether serum quantitative HBcrAg (qHBcrAg) was a satisfactory surrogate marker of intrahepatic covalently closed circular DNA (cccDNA). A total of 139 patients with liver biopsy were enrolled, consisting of 59 patients in immune tolerance (IT) phase, 52 patients in immune clearance (IC) phase, 18 patients in low-replication (LR) phase, and 10 patients in reactivation phase. All patients in IC phase have received entecavir (ETV) therapy, and 32 of them undergone a second liver biopsy at 24 months. Among those patients, qHBcrAg was strongly correlated with intrahepatic cccDNA, which is superior to that of qHBsAg and HBV DNA. And similar findings were also observed in patients in IT, IC, LR and reactivation phases. Among the 32 ETV-treated patients with a second liver biopsy in IC phase, the decline of intrahepatic cccDNA was accompanied by changes in both qHBcrAg and qHBsAg. However, as compared to qHBsAg, the change of qHBcrAg was more strongly associated with intrahepatic cccDNA-decline. In summary, serum qHBcrAg should be a satisfactory surrogate of intrahepatic HBV cccDNA in CHB patients.

Monoclonal antibodies (mAbs) targeting calcitonin gene-related peptide (CGRP) signaling are being explored as prophylactic treatments for migraine. Erenumab (AMG 334) is the first potent, selective, and competitive human mAb antagonist of the CGRP receptor. We report the data from two phase I studies assessing the safety, pharmacokinetics (PK), and pharmacodynamics of single and multiple administrations of erenumab in healthy subjects and patients with migraine. The results indicate that the PK profile of erenumab is nonlinear from 1 mg to 70 mg and the linear portion of the clearance from 70 mg to 210 mg is consistent with other human immunoglobulin G2 antibodies. Single doses of erenumab resulted in >75% inhibition of capsaicin-induced dermal blood flow, with no apparent dose-dependency for erenumab ≥21 mg. Erenumab was generally well tolerated, with an acceptable safety profile, supporting further clinical development of erenumab for migraine prevention.

Purpose Our goals are to test the effect of acute lung infection on tumor metastasis and to investigate the underlying mechanisms. Experimental Design We combined bacteria- and lipopolysaccharide (LPS)-induced acute lung injury/inflammation (ALI) mouse models with mouse metastatic models to study the effect of acute inflammation on lung metastasis in mice. The mechanisms were invested in ex vivo, in vitro, and in vivo studies. Results Both bacteria- and LPS-induced acute lung injury/inflammation significantly enhanced lung metastasis of four tail vein-injected mouse tumor cell lines. Bacteria also enhanced lung metastasis when 4T1 cells orthotopically injected. The broncheoalveolar lavage fluid (BALF) from LPS- or bacteria- injected mice stimulated migration of tumor cells. In vivo tracking of metastatic RM-9 cells showed that bacterial injection enhanced early dissemination of tumor cells to the lung. The majority of the BALF migratory activity could be blocked by AMD3100, a CXCR4 inhibitor. All tested cell lines expressed CXCR4. The levels of extracellular ubiquitin (Ub), but not SDF-1, in BALF were significantly increased by LPS. Ub was able to induce AMD3100-sensitive migration of tumor cells. Finally, the anti-bacterial amoxicillin and AMD3100 blocked the enhancement effect of bacterial infection on tumor metastasis. Conclusions Acute lung infection dramatically increased cancer cell homing to the lung and lung metastasis. This may be due to an alteration of the lung microenvironment and preparation of a favorable metastatic “niche”. This effect was seen in multiple cancer types and thus may have broad applications for cancer patients in prevention and/or treatment of metastasis.