Sjögren's Syndrome (SjS) results in loss of salivary and lacrimal gland excretion due to an autoimmune attack on these secretory glands. Conventional SjS treatments address the symptoms, but not the ...cause of disease. Recognizing this deficit of treatments to reverse SjS disease, studies were pursued using the fimbriae from enterotoxigenic E. coli, colonization factor antigen I (CFA/I), which has anti-inflammatory properties. To determine if CFA/I fimbriae could attenuate SjS-like disease in C57BL/6.NOD-Aec1Aec2 (SjS) females, the Lactococcus lactis (LL) 301 strain was developed to chromosomally express the cfaI operon. Western blot analysis confirmed CFA/I protein expression, and this was tested in SjS females at different stages of disease. Repeated dosing with LL 301 proved effective in mitigating salivary flow loss and in reducing anti-nuclear antibodies (ANA) and inflammation in the submandibular glands (SMGs) in SjS females and in restoring salivary flow in diseased mice. LL 301 treatment reduced proinflammatory cytokine production with concomitant increases in TGF-β
CD25
CD4
T cells. Moreover, LL 301 treatment reduced draining lymph and SMG follicular T helper (Tfh) cell levels and proinflammatory cytokines, IFN-γ, IL-6, IL-17, and IL-21. Such evidence points to the therapeutic capacity of CFA/I protein to suppress SjS disease and to have restorative properties in combating autoimmune disease.
The antitumor efficacy of cancer immunotherapy can correlate with the presence of certain bacterial species within the gut microbiome. However, many of the molecular mechanisms that influence host ...response to immunotherapy remain elusive. In this study, we show that members of the bacterial genus
improve checkpoint inhibitor immunotherapy in mouse tumor models. Active enterococci express and secrete orthologs of the NlpC/p60 peptidoglycan hydrolase SagA that generate immune-active muropeptides. Expression of SagA in nonprotective
was sufficient to promote immunotherapy response, and its activity required the peptidoglycan sensor NOD2. Notably, SagA-engineered probiotics or synthetic muropeptides also augmented anti-PD-L1 antitumor efficacy. Taken together, our data suggest that microbiota species with specialized peptidoglycan remodeling activity and muropeptide-based therapeutics may enhance cancer immunotherapy and could be leveraged as next-generation adjuvants.
As early as the 1920s, the eminent physician and chemist, Otto Warburg, nominated for a second Nobel Prize for his work on fermentation, observed that the core metabolic signature of cancer cells is ...a high glycolytic flux. Warburg averred that the prime mover of cancer is defective mitochondrial respiration, which drives a switch to an alternative energy source, aerobic glycolysis in lieu of Oxidative Phosphorylation (OXPHOS), in an attempt to maintain cellular viability and support critical macromolecular needs. The cell, deprived of mitochondrial ATP production, must reprogram its metabolism as a secondary survival mechanism to maintain sufficient ATP and NADH levels for macromolecule production, membrane integrity and DNA synthesis as well as maintenance of membrane ionic gradients. A time-tested method to identify and disrupt criminal activity is to "follow the money" since the illicit proceeds from crime are required to underwrite it. By analogy, strategies to target cancer involve following and disrupting the flow of ATP and NADH, the energetic and redox "currencies" of the cell, respectively, since the tumor requires high levels of ATP and NADH, not only for metastasis and proliferation, but also, on a more basic level, for survival. Accordingly, four broad ATP reduction strategies to impact and potentially derail cancer energy production are highlighted herein: 1) small molecule energy-restriction mimetic agents (ERMAs) that target various aspects of energy metabolism, 2) reduction of energy 'subsidization' with autophagy inhibitors, 3) acceleration of ATP turnover to increase energy inefficiency, and 4) dietary energy restriction to limit the energy supply.
Oncolytic viruses have had a tumultuous course, from the initial anecdotal reports of patients having antineoplastic effects after natural viral infections a century ago to the development of current ...cutting-edge therapies in clinical trials. Adenoviruses have long been the workhorse of virotherapy, and we review both the scientific and the not-so-scientific forces that have shaped the development of these therapeutics from wild-type viral pathogens, turning an old foe into a new friend. After a brief review of the mechanics of viral replication and how it has been modified to engineer tumor selectivity, we give particular attention to ONYX-015, the forerunner of virotherapy with extensive clinical testing that pioneered the field. The findings from those as well as other oncolytic trials have shaped how we now view these viruses, which our immune system has evolved to vigorously attack, as promising immunotherapy agents.
Summary Background Epigenetic alterations have been strongly associated with tumour formation and resistance to chemotherapeutic drugs, and epigenetic modifications are an attractive target in cancer ...research. RRx-001 is activated by hypoxia and induces the generation of reactive oxygen and nitrogen species that can epigenetically modulate DNA methylation, histone deacetylation, and lysine demethylation. The aim of this phase 1 study was to assess the safety, tolerability, and pharmacokinetics of RRx-001. Methods In this open-label, dose-escalation, phase 1 study, we recruited adult patients (aged >18 years) with histologically or cytologically confirmed diagnosis of advanced, malignant, incurable solid tumours from University of California at San Diego, CA, USA, and Sarah Cannon Research Institute, Nashville, TN, USA. Key eligibility criteria included evaluable disease, Eastern Cooperative Group performance status of 2 or less, an estimated life expectancy of at least 12 weeks, adequate laboratory parameters, discontinuation of all previous antineoplastic therapies at least 6 weeks before intervention, and no residual side-effects from previous therapies. Patients were assigned to receive intravenous infusions of RRx-001 at increasing doses (10 mg/m2 , 16·7 mg/m2 , 24·6 mg/m2 , 33 mg/m2 , 55 mg/m2 , and 83 mg/m2 ) either once or twice-weekly for at least 4 weeks, with at least three patients per dose cohort and allowing a 2-week observation period before dose escalation. Samples for safety and pharmacokinetics analysis, including standard chemistry and haematological panels, were taken on each treatment day. The primary objective was to assess safety, tolerability, and dose-limiting toxic effects of RRx-001, to determine single-dose pharmacokinetics, and to identify a recommended dose for phase 2 trials. All analyses were done per protocol. Accrual is complete and follow-up is still on-going. This trial is registered with ClinicalTrials.gov , number NCT01359982. Findings Between Oct 10, 2011, and March 18, 2013, we enrolled 25 patients and treated six patients in the 10 mg/m2 cohort, three patients in the 16·7 mg/m2 cohort, three patients in the 24·6 mg/m2 cohort, four patients in the 33 mg/m2 cohort, three patients in the 55 mg/m2 , and six patients in the 83 mg/m2 cohort. Pain at the injection site, mostly grade 1 and grade 2, was the most common adverse event related to treatment, experienced by 21 (84%) patients. Other common drug-related adverse events included arm swelling or oedema (eight 32% patients), and vein hardening (seven 28% patients). No dose-limiting toxicities were observed. Time constraints related to management of infusion pain from RRx-001 resulted in a maximally feasible dose of 83 mg/m2 . Of the 21 evaluable patients, one (5%) patient had a partial response, 14 (67%) patients had stable disease, and six (29%) patients had progressive disease; all responses were across a variety of tumour types. Four patients who had received RRx-001 were subsequently rechallenged with a treatment that they had become refractory to; all four responded to the rechallenge. Interpretation RRx-001 is a well-tolerated novel compound without clinically significant toxic effects at the tested doses. Preliminary evidence of activity is promising and, on the basis of all findings, a dose of 16·7 mg/m2 was recommended as the targeted dose for phase 2 trials. Funding EpicentRx (formerly RadioRx).
Inflammatory bowel disease (IBD) is characterized by gastrointestinal inflammation comprised of Crohn’s disease and ulcerative colitis. Centers for Disease Control and Prevention report that 1.3% of ...the population of the United States (approximately 3 million people) were affected by the disease in 2015, and the number keeps increasing over time. IBD has a multifactorial etiology, from genetic to environmental factors. Most of the IBD treatments revolve around disease management, by reducing the inflammatory signals. We previously identified the surface layer protein A (SlpA) of Lactobacillus acidophilus that possesses anti-inflammatory properties to mitigate murine colitis. Herein, we expressed SlpA in a clinically relevant, food-grade Lactococcus lactis to further investigate and characterize the protective mechanisms of the actions of SlpA. Oral administration of SlpA-expressing L. lactis (R110) mitigated the symptoms of murine colitis. Oral delivery of R110 resulted in a higher expression of IL-27 by myeloid cells, with a synchronous increase in IL-10 and cMAF in T cells. Consistent with murine studies, human dendritic cells exposed to R110 showed exquisite differential gene regulation, including IL-27 transcription, suggesting a shared mechanism between the two species, hence positioning R110 as potentially effective at treating colitis in humans.
Targeted disruption of the gene encoding MEK kinase 1 (MEKK1), a mitogen-activated protein kinase (MAPK) kinase kinase, defined its function in the regulation of MAPK pathways and cell survival. ...MEKK1$^{-/-}$ embryonic stem cells from mice had lost or altered responses of the c-Jun amino-terminal kinase (JNK) to microtubule disruption and cold stress but activated JNK normally in response to heat shock, anisomycin, and ultraviolet irradiation. Activation of JNK was lost and that of extracellular signal-regulated protein kinase (ERK) was diminished in response to hyperosmolarity and serum factors in MEKK1$^{-/-}$ cells. Loss of MEKK1 expression resulted in a greater apoptotic response of cells to hyperosmolarity and microtubule disruption. When activated by specific stresses that alter cell shape and the cytoskeleton, MEKK1 signals to protect cells from apoptosis.
The ability to diagnose prostate carcinoma would be improved by the detection of a tumor-associated antigen. P504S, a cytoplasmic protein, was recently identified by cDNA library subtraction in ...conjunction with high throughput microarray screening from prostate carcinoma. The aim of this study was to establish the pattern of expression of P504S in prostate carcinoma and benign prostatic tissue. A total of 207 cases, including 137 cases of prostate carcinoma and 70 cases of benign prostate, from prostatectomies (n = 77), prostate needle biopsies (n = 112), and transurethral prostate resections (n = 18) were examined by immunocytochemistry for P504S. P504S showed strong cytoplasmic granular staining in 100% of prostate carcinomas regardless of Gleason scores and diffuse (>75% of tumor) staining in 92% of cases. In contrast, 171 of 194 (88%) of benign prostates, including 56 of 67 (84%) benign prostate cases and 115 of 127 (91%) cases of benign glands adjacent to cancers were negative for P504S. The remainders of benign prostates were focally and weakly positive for P504S. The staining pattern of these normal glands was different and easily distinguishable from that observed in prostate carcinoma. Expression of P504S was not found in basal cell hyperplasia, urothelial cells/metaplasia and small atrophic glands that may mimic prostate carcinoma. Our findings indicate that P504S is a highly sensitive and specific positive marker for prostate carcinoma.
MEK kinases (MEKKs) 1, 2, 3 and 4 are members of sequential kinase pathways that regulate MAP kinases including c‐Jun NH2‐terminal kinases (JNKs) and extracellular regulated kinases (ERKs). Confocal ...immunofluorescence microscopy of COS cells demonstrated differential MEKK subcellular localization: MEKK1 was nuclear and in post‐Golgi vesicular‐like structures; MEKK2 and 4 were localized to distinct Golgi‐associated vesicles that were dispersed by brefeldin A. MEKK1 and 2 were activated by EGF, and kinase‐inactive mutants of each MEKK partially inhibited EGF‐stimulated JNK activity. Kinase‐inactive MEKK1, but not MEKK2, 3 or 4, strongly inhibited EGF‐stimulated ERK activity. In contrast to MEKK2 and 3, MEKK1 and 4 specifically associated with Rac and Cdc42 and kinase‐inactive mutants blocked Rac/Cdc42 stimulation of JNK activity. Inhibitory mutants of MEKK1–4 did not affect p21‐activated kinase (PAK) activation of JNK, indicating that the PAK‐regulated JNK pathway is independent of MEKKs. Thus, in different cellular locations, specific MEKKs are required for the regulation of MAPK family members, and MEKK1 and 4 are involved in the regulation of JNK activation by Rac/Cdc42 independent of PAK. Differential MEKK subcellular distribution and interaction with small GTP‐binding proteins provides a mechanism to regulate MAP kinase responses in localized regions of the cell and to different upstream stimuli.
PDF
