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Background: Low back pain is a global health problem that originated mainly from intervertebral disc degeneration (IDD). Autophagy, negatively regulated by the phosphatidylinositol 3‐kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway, prevents metabolic and degenerative diseases by removing and recycling damaged cellular components. Despite growing evidence that autophagy occurs in the intervertebral disc, the regulation of disc cellular autophagy is still poorly understood. Methods: Annulus fibrosus (rAF) cell cultures derived from healthy female rabbit discs were used to test the effect of autophagy inhibition or activation on disc cell fate and matrix homeostasis. Specifically, different chemical inhibitors including rapamycin, 3‐methyladenine, MK‐2206, and PP242 were used to modulate activities of different proteins in the PI3K/Akt/mTOR signaling pathway to assess IL‐1β‐induced cellular senescence, apoptosis, and matrix homeostasis in rAF cells grown under nutrient‐poor culture condition. Results: Rapamycin, an inhibitor of mTOR complex 1 (mTORC1), reduced the phosphorylation of mTOR and its effector p70/S6K in rAF cell cultures. Rapamycin also induced autophagic flux as measured by increased expression of key autophagy markers, including LC3 puncta number, LC3‐II expression, and cytoplasmic HMGB1 intensity and decreased p62/SQSTM1 expression. As expected, IL‐1β stimulation promoted rAF cellular senescence, apoptosis, and matrix homeostatic imbalance with enhanced aggrecanolysis and MMP‐3 and MMP‐13 expression. Rapamycin treatment effectively mitigated IL‐1β‐mediated inflammatory stress changes, but these alleviating effects of rapamycin were abrogated by chemical inhibition of Akt and mTOR complex 2 (mTORC2). Conclusions: These findings suggest that rapamycin blunts adverse effects of inflammation on disc cells by inhibiting mTORC1 to induce autophagy through the PI3K/Akt/mTOR pathway that is dependent on Akt and mTORC2 activities. Hence, our findings identify autophagy, rapamycin, and PI3K/Akt/mTOR signaling as potential therapeutic targets for IDD treatment. [ABSTRACT FROM AUTHOR]

The immune system interacts with many nominal 'danger' signals, endogenous danger‐associated (DAMP), exogenous pathogen (PAMP) and allergen (AAMP)‐associated molecular patterns. The immune context under which these are received can promote or prevent immune activating or inflammatory mechanisms and may orchestrate diverse immune responses in allergy and cancer. Each can act either by favouring a respective pathology or by supporting the immune response to confer protective effects, depending on acuity or chronicity. In this Position Paper under the collective term danger signals or DAMPs, PAMPs and AAMPs, we consider their diverse roles in allergy and cancer and the connection between these in AllergoOncology. We focus on their interactions with different immune cells of the innate and adaptive immune system and how these promote immune responses with juxtaposing clinical outcomes in allergy and cancer. While danger signals present potential targets to overcome inflammatory responses in allergy, these may be reconsidered in relation to a history of allergy, chronic inflammation and autoimmunity linked to the risk of developing cancer, and with regard to clinical responses to anti‐cancer immune and targeted therapies. Cross‐disciplinary insights in AllergoOncology derived from dissecting clinical phenotypes of common danger signal pathways may improve allergy and cancer clinical outcomes. [ABSTRACT FROM AUTHOR]

Introduction: Preoperative autophagy inhibition with hydroxychloroquine (HCQ) in combination with gemcitabine in pancreatic adenocarcinoma (PDAC) has been shown to be safe and effective in inducing a serum biomarker response and increase resection rates in a previous phase I/II clinical trial. We aimed to analyze the long‐term outcomes of preoperative HCQ with gemcitabine for this cohort. Methods: A review of patients enrolled between July 2010 and February 2013 in the completed phase I/II single arm (two doses of fixed‐dose gemcitabine (1500 mg/m2) in combination with oral hydroxychloroquine administered for 31 consecutive days until the day of surgery for high‐risk pancreatic cancer) was undertaken. Progression‐free survival (PFS) and overall survival analysis (OS) using Kaplan–Meier estimates were performed. Results: Of 35 patients initially enrolled, 29 patients underwent surgical resection (median age at diagnosis: 62 years, 45% females). Median duration of follow‐up was 7.5 years. There was a median 15% decrease in the serum CA19‐9 levels following completion of neoadjuvant therapy and 83% of the cohort underwent a pancreaticoduodenectomy, 7 (24%) patients had a concomitant venous resection. On histopathology, 14 (48%) patients had at least a partial treatment response. The median PFS and OS were 11 months (95% Confidence interval [CI]: 7–28) and 31 months (95% CI: 13–47), respectively, while 9 (31%) patients survived beyond 5 years from diagnosis; a rate that compares very favorably with contemporaneous series. Conclusion: Compared to historical data, neoadjuvant autophagy inhibition with HCQ plus gemcitabine is associated with encouraging long‐term survival for patients with PDAC. [ABSTRACT FROM AUTHOR]

SMAD4, a tumor suppressor gene, is lost in up to 60%–90% of pancreatic adenocarcinomas (PDAs). Loss of SMAD4 allows tumor progression by upregulating autophagy, a cell survival mechanism that counteracts apoptosis and allows intracellular recycling of macromolecules. Hydroxychloroquine (HCQ) is an autophagy inhibitor. We studied whether HCQ treatment in SMAD4 deficient PDA may prevent therapeutic resistance induced by autophagy upregulation. We retrospectively analyzed the SMAD4 status of patients with PDA enrolled in two prospective clinical trials evaluating pre‐operative HCQ. The first dose escalation trial demonstrated the safety of preoperative gemcitabine with HCQ (NCT01128296). More recently, a randomized trial of gemcitabine/nab‐paclitaxel +/− HCQ evaluated Evans Grade histopathologic response (NCT01978184). The effect of SMAD4 loss on response to HCQ and chemotherapy was studied for association with clinical outcome. Fisher's exact test and log‐rank test were used to assess response and survival. Fifty‐two patients receiving HCQ with neoadjuvant chemotherapy were studied. Twenty‐five patients had SMAD4 loss (48%). 76% of HCQ‐treated patients with SMAD4 loss obtained a histopathologic response greater than or equal to 2A, compared with only 37% with SMAD4 intact (p = 0.006). Although loss of SMAD4 has been associated with worse outcomes, in the current study, loss of SMAD4 was not associated with a detriment in median overall survival in HCQ‐treated patients (34.43 months in SMAD4 loss vs. 27.27 months in SMAD4 intact, p = 0.18). The addition of HCQ to neoadjuvant chemotherapy in patients with PDA may improve treatment response in those with SMAD4 loss. Further study of the relationship among SMAD4, autophagy, and treatment outcomes in PDA is warranted. [ABSTRACT FROM AUTHOR]

Recent studies defined a potentially important role of the microbiome in modulating pancreatic ductal adenocarcinoma (PDAC) and responses to therapies. We hypothesized that antibiotic usage may predict outcomes in patients with PDAC. We retrospectively analyzed clinical data of patients with resectable or metastatic PDAC seen at MD Anderson Cancer from 2003 to 2017. Demographic, chemotherapy regimen and antibiotic use, duration, type, and reason for indication were recorded. A total of 580 patients with PDAC were studied, 342 resected and 238 metastatic patients, selected retrospectively from our database. Antibiotic use, for longer than 48 hrs, was detected in 209 resected patients (61%) and 195 metastatic ones (62%). On resectable patients, we did not find differences in overall survival (OS) or progression‐free survival (PFS), based on antibiotic intake. However, in the metastatic cohort, antibiotic consumption was associated with a significantly longer OS (13.3 months vs. 9.0 months, HR 0.48, 95% CI 0.34–0.7, p = 0.0001) and PFS (4.4 months vs. 2 months, HR 0.48, 95% CI 0.34–0.68, p = <0.0001). In multivariate analysis, the impact of ATB remained significant for PFS (HR 0.59, p = 0.005) and borderline statistically significant for OS (HR 0.69, p = 0.06). When we analyzed by chemotherapy regimen, we found that patients who received gemcitabine‐based chemotherapy as first‐line therapy (n = 118) had significantly prolonged OS (HR 0.4, p 0.0013) and PFS (HR 0.55, p 0.02) if they received antibiotics, while those receiving 5FU‐based chemotherapy (n = 98) had only prolonged PFS (HR 0.54, p = 0.03). Antibiotics‐associated modulation of the microbiome is associated with better outcomes in patients with metastatic PDAC. We have analyzed the effect of antibiotics' intake on two cohorts of patients with pancreatic adenocarcinoma, resectable, and metastatic. We have found that on the metastatic cohort, antibiotics use was significantly associated with better outcomes, particularly, on patients that received gemcitabine based‐chemotherapy as the first line. [ABSTRACT FROM AUTHOR]

Pathogen-associated molecular pattern molecules ( PAMPs) are derived from microorganisms and recognized by pattern recognition receptor ( PRR)-bearing cells of the innate immune system as well as many epithelial cells. In contrast, damage-associated molecular pattern molecules ( DAMPs) are cell-derived and initiate and perpetuate immunity in response to trauma, ischemia, and tissue damage, either in the absence or presence of pathogenic infection. Most PAMPs and DAMPs serve as so-called 'Signal 0s' that bind specific receptors [Toll-like receptors, NOD-like receptors, RIG-I-like receptors, AIM2-like receptors, and the receptor for advanced glycation end products ( RAGE)] to promote autophagy. Autophagy, a conserved lysosomal degradation pathway, is a cell survival mechanism invoked in response to environmental and cellular stress. Autophagy is inferred to have been present in the last common eukaryotic ancestor and only to have been lost by some obligatory intracellular parasites. As such, autophagy represents a unifying biology, subserving survival and the earliest host defense strategies, predating apoptosis, within eukaryotes. Here, we review recent advances in our understanding of autophagic molecular mechanisms and functions in emergent immunity. [ABSTRACT FROM AUTHOR]

Wound healing represents a highly regulated, orchestrated response of cells recruited to sites of injury. High molecular weight hyaluronic acid was conjugated with monoclonal antibodies to the cytokine interleukin-1β to create a matrix-forming polymer capable of modifying healing. Using gel electrophoresis and fluorescence immunosorbent assays, we determined a degree of antibody functionalization per hyaluronic acid chain of 13.6±1.6%. The biological activity of the conjugate in vitro, measured using a nuclear factor-κB translocation assay in activated THP-1 monocytes, was comparable in inhibiting cytokine signaling to a similar level as the unconjugated antibody. Incisional wound studies in Sprague–Dawley rats indicates that viscous hyaluronic acid solutions were immunologically active, but covalent functionalization with antibodies against tumor necrosis factor-α and interleukin-1β resulted in significant reductions in the inflammatory response. Covalent attachment of cytokine-neutralizing antibodies to matrix-forming polymers could lead to the development of materials capable of locally regulating wound healing and inflammatory responses in the setting of tissue regeneration. [ABSTRACT FROM AUTHOR]

The development of biologic therapies for patients with cancer has in part been impeded by the extraordinary complexity and intrinsic feedback mechanisms promoting homeostasis in tissue injury, repair, inflammation, and immunity. Recombinant interleukin 2 (IL-2) therapy was initiated in 1984 based on its role as the prototypic T-cell growth factor, with novel roles deduced late after its FDA approval in regulating not only effector T cells but also regulatory T cells. Complicating its application, even in the most sophisticated centers, has been the manageable but difficult toxicities attendant on its use in spite of clear evidence of complete responses in 5–10% of treated patients with melanoma and renal cell carcinoma with extraordinary durability lasting now for almost 25 years, thus tantamount to “cures.” Although efforts have been made to diminish toxicity or enhance efficacy the only substantive advance in combination therapy has been the application of tumor-infiltrating lymphocytes and the antibody to CTLA4. A deeper understanding of the “limiting” toxicity associated with mild flu-like symptoms and more debilitating cytokine “storm” not forthcoming. Here we propose the notion that the systemic syndrome associated with IL-2 administration is due to global cytokine-induced autophagy and temporally limited tissue dysfunction. The possible role of autophagy inhibitors to enhance efficacy and limit toxicity as well as possible problems with this approach are considered. [ABSTRACT FROM AUTHOR]

The response to pathogens and damage in plants and animals involves a series of carefully orchestrated, highly evolved, molecular mechanisms resulting in pathogen resistance and wound healing. In metazoans, damage- or pathogen-associated molecular pattern molecules (DAMPs, PAMPs) execute precise intracellular tasks and are also able to exert disparate functions when released into the extracellular space. The emergent consequence for both inflammation and wound healing of the abnormal extracellular persistence of these factors may underlie many clinical disorders. DAMPs/PAMPs are recognized by hereditable receptors including the Toll-like receptors, the NOD1-like receptors and retinoic-acid-inducible gene I-like receptors, as well as the receptor for advanced glycation end products. These host molecules ‘sense’ not only pathogens but also misfolded/glycated proteins or exposed hydrophobic portions of molecules, activating intracellular cascades that lead to an inflammatory response. Equally important are means to not only respond to these molecules but also to eradicate them. We have speculated that their destruction through oxidative mechanisms normally exerted by myeloid cells, such as neutrophils and eosinophils, or their persistence in the setting of pathologic extracellular reducing environments, maintained by exuberant necrotic cell death and/or oxidoreductases, represent important molecular means enabling chronic inflammatory states. [ABSTRACT FROM AUTHOR]

Aim: Adenocarcinoma of the prostate is one of the most frequently diagnosed non-cutaneous cancers and the second leading cause of cancer-related deaths among men in the United States. To fully understand the role of ceramide during apoptosis induced by androgen ablation, we modified the levels of intracellular ceramide by pharmacological agents as well as through serum deprivation in androgen-dependent and independent cell lines. Methods: Ceramide levels were modified using N-oleoylethanolamine (NOE), sphingosine-1-phosphate (S1P) as well as through serum deprivation, in LNCaP, DU145 and PC-3 prostate cancer cells. Various methods including nonyl acridine orange staining, propidium iodide staining/cell cycle analysis and lipid analysis were utilized. Results: Our results demonstrate that the inhibition of acid ceramidase by NOE enhances the intracellular ceramide levels induced by androgen ablation in androgen-dependent LNCaP cells, and is accompanied by an increase in apoptotic cells. Sphingosine 1-phosphate had no effect in rescuing LNCaP cells from apoptosis induced by androgen ablation. Our results also show that serum deprivation causes intracellular ceramide accumulation and apoptosis in androgen-independent prostate cancer cells. Conclusions: Our studies indicate that the increase in intracellular ceramide itself, but not the balance between ceramide and S1P, determines whether LNCaP cells undergo apoptosis. Our results also show that the increase in intracellular ceramide strongly correlates with apoptosis induced by serum deprivation even in androgen-independent prostate cancer cell lines. [ABSTRACT FROM AUTHOR]

Tumor immune responses, including some immunotherapy strategies, can fail because of a number of reasons, such as poor tumor cell immunogenicity or local suppressive cytokine release by dendritic cells (DC) at tumor sites. The retroviral transfer of T-cell receptor (TCR) genes encoding tumor-specific receptors into T cells is a fascinating approach to bypass antigen-presenting cells and allow T cells to directly recognize antigen. It also allows the generation and expansion of potent antitumor cytotoxic T lymphocytes with defined cancer antigen specificities more readily than naive T cells. However, interleukin-10 (IL-10)-exposed dendritic cells (IL-10-DC) have been labeled tolerogenic because of the suppressive effects they have on T cell responses. Whether TCR gene-transduced effector CD8+ T cells can break through suppressive functions mediated by IL-10-DC is not known. In the current study, we demonstrate the role of IL-10 in modifying the function of DC that otherwise would activate potent TCR gene-transduced T cells against tumor antigens. TCR gene-transduced T cells maintained their cytolytic activity in the presence of DC exposed to low doses of IL-10 during maturation; however, they lost this activity in an antigen-specific manner when exposed to DC matured with high doses of IL-10. ( Cancer Sci 2005; 96: 897–902) [ABSTRACT FROM AUTHOR]

Background The tetracycline-regulatable system is one of the most valuable tools for controlling gene expression. In its current form, however, the system is less than ideal for in vivo or gene therapy uses due to difficulties in set-up procedures, high basal leakiness, and unpredictable delivery and efficiency. Methods To address these issues, we have devised a second generation of tetracycline-regulated promoters (TREs). The second-generation TRE (SG-TRE) contains a shortened cytomegalovirus (CMV) minimal promoter together with eight tet operator sequences positioned in an optimized manner upstream of the TATA box. This construct displays far greater reduction in basal leakiness than maximal transgene expression. Conversely, maximal transgene expression is increased to a greater degree than basal leakiness by post-translational stabilization with bovine growth hormone poly A. Results In transient studies, the SG-TRE displays over 100 000-fold regulation efficiency in HeLa cells at 1:1 ratio of transactivator to reporter plasmid in the Tet-Off system. This novel promoter achieves a regulation efficiency 500- to 1000-fold higher than that of the original TRE (PhCMV*-1) in HeLa cells by displaying undetectable levels of basal leakiness without compromised maximal expression. In other cell lines, the SG-TRE proves to be more efficient than the original PhCMV*-1 in a cell-dependent manner. Furthermore, the SG-TRE preserves its enhanced regulation efficiency and its reduced basal leakiness in the context of a single positive feedback regulatory vector that presents ease of delivery of the system for use in vivo. Finally, in vivo, the biological function of granulocyte-macrophage colony stimulating factor is tightly regulated in the context of SG-TRE delivered via adeno-associated viruses. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Objectives Dendritic cells, the most potent of the antigen-presenting cells, have been widely studied as a promising tool for antitumor immunotherapies. However, little has been determined about the efficacy of dendritic cell-based therapy for the treatment of squamous cell carcinoma (SCC) because there are no known SCC-specific antigens. Recent reports indicate that dendritic cells can acquire antigens in the form of apoptotic cells and induce cytotoxic T-lymphocyte responses. The aim of this study was to test the feasibility of adoptive dendritic cell immunotherapy against SCC by using apoptotic tumor cells as a source of tumor antigens. Study Design A poorly immunogenic SCC line KLN 205 was used to make subcutaneous tumors on the flank of DBA2/J syngeneic mice. Bone marrow-derived dendritic cells were pulsed with ultraviolet B-irradiated (apoptotic) KLN 205 cells in vitro and transferred to the opposite flank subcutaneously. Some of the animals received simultaneous intraperitoneal injections of low-dose interleukin-2. Results When combined with interleukin-2, adoptive transfers of dendritic cells that were pulsed with apoptotic SCC significantly suppressed the tumor growth ( P <.001) without notable side effects. Splenic T cells of treated mice produced greater amounts of interferon-γ when restimulated with the relevant tumor ( P <.001) as compared with control groups, indicative of an effective T-cell-mediated systemic immune response. Conclusion Adoptive transfer of dendritic cells pulsed with apoptotic tumor cells as a source of tumor antigens, can elicit effective antitumor responses in the poorly immunogenic SCC model when combined with interleukin-2. [ABSTRACT FROM AUTHOR]

Interleukin-12 (IL-12) is an immunostimulatory agent with very promising antitumor activity. Using a retroviral expression vector, the authors have successfully transduced the genes encoding the two subunits of murine IL-12 to the squamous cell carcinoma cell line, SCC VII. Once IL-12 gene transcription and protein production were successfully verified, IL-12 expression was found to inhibit the establishment of SCC VII tumors in syngeneic C3H/HeJ mice inoculated with 1 x 10(6) SCC VII/IL-12 viable tumor cells. Mice immunized in this manner and rechallenged with parent SCC VII were capable of rejecting tumor up to 40% of the time. Treatment of established SCC VII tumors with irradiated IL-12-producing tumors cells led to significant tumor regression in a high percentage of animals. [ABSTRACT FROM AUTHOR]