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Apoptosis of cardiomyocytes is a critical outcome of myocardial ischemia-reperfusion injury (MIRI), which leads to the permanent impairment of cardiac function. Upregulated E2F1 is implicated in inducing cardiomyocyte apoptosis, and thus intervention of the E2F1 signaling pathway

Background Few clinical research studies with long‐term follow‐up have revealed whether cardiopulmonary bypass (CPB) increases the risk of postoperative distant metastasis in patients with giant refractory thoracic tumors. The present study evaluated the risk of distant metastasis after surgery utilizing CPB with long‐term follow‐up. Methods Clinical data for patients with giant refractory thoracic tumors who underwent resection with the use of CPB in the Second Affiliated Hospital of Soochow University during the past 11 years were retrospectively reviewed. Results Of the 14 patients with giant refractory thoracic tumors who had undergone surgery under CPB, 10 patients (71.4%) were completely resected. Twelve patients were followed up for 13–127 months with 10 patients were completely resected and two patients could not be completely resected due to severe tissue invasion. Three patients (25%) suffered from distant metastasis, and four patients (33.3%) experienced local recurrence. Only one patient (1/10) with complete resection suffered from distant metastasis, while two patients (2/10) experienced local recurrence. Two patients (2/2) with major resection suffered from both distant metastasis and local recurrence. Median overall survival for patients who have been regularly followed up was 50 months with 1‐, 5‐, and 10‐year survival of 100%, 75%, and 66.7%. No difference was found between the distant metastasis survival and the local recurrence survival. (p = 0.99). Conclusions CPB is an effective strategy for complete resection of the giant refractory thoracic tumors with an acceptable risk of postoperative distant metastasis for some patients., Giant refractory thoracic tumors of various pathological types invade the surrounding tissues and organs with serious consequences. The main risks during the conventional thoracic surgery are the damage to the surrounding important tissues and organs and instability of the respiratory and circulation systems. Cardiopulmonary bypass is an effective strategy for complete resection of giant refractory thoracic tumors without an extremely high risk of postoperative distant metastasis for some patients.

Manipulating intracellular levels of reactive oxygen and nitrogen species (RONS) is of great potential for cancer treatment. Inspired by the natural mechanism of a radical storm in inflammatory cells via activated and regulatable biocatalysis, the authors herein report a self-powered nanozyme that can enable RONS production in tumor cells via cascade reactions. The nanozymes are constructed via glucose oxidase (GOx)-templated inverse microemulsion polymerization from acrylamide, arginine-acrylamide, ferrocene-acrylate, and N,N'-bis(acryloyl)cystamine, followed by surface coating with hyaluronic acid. After targeted delivery into cancer cells, the nanozymes are dissociated by intracellular glutathione to release GOx, which decomposed glucose to generate gluconic acid and H

Cytosolic protein delivery holds great potential for the development of protein-based biotechnologies and therapeutics. Currently, cytosolic protein delivery is mainly achieved with the assistance of various carriers. Herein, we present a universal and effective strategy for carrier-free cytosolic protein delivery via metabolic glycoengineering and bioorthogonal click reactions. Ac4ManNAz (AAM), an azido-modified N-acetylmannosamine analogue, was first employed to label tumor cell surfaces with abundant azido groups via glycometabolism. Then, proteins including RNase A, cytochrome C (Cyt C), and bovine serum albumin (BSA) were covalently modified with dibenzocyclooctyne (DBCO). Based on the highly efficient bioorthogonal click reactions between DBCO and azido, DBCO-modified proteins could be efficiently internalized by azido-labeled cancer cells. RNase A-DBCO could largely maintain its enzymatic activity and, thus, led to notable anti-tumor efficacy in HeLa and B16F10 cells in vitro and in B16F10 xenograft tumors in vivo. This study therefore provides a simple and powerful approach for carrier-free protein delivery and would have broad applicability in anti-tumor protein therapy.

It remains a huge challenge to develop methanol oxidation electrocatalysts with remarkable catalytic activity and anti-CO poisoning capability. Herein, PtIrNi and PtIrCo jagged nanowires are successfully synthesized via a facile wet-chemical approach. Pt and Ir components are concentrated in the exterior and Ni is concentrated in the interior of PtIrNi jagged nanowires, while PtIrCo jagged nanowires feature the homogeneous distribution of constituent metals. The PtIrNi and PtIrCo jagged nanowires exhibit mass activities of 1.88 A/mg

Insufficient intratumoral penetration greatly hurdles the anticancer performance of nanomedicine. To realize highly efficient tumor penetration in a precisely and spatiotemporally controlled manner, far-red light-responsive nanoclusters (NCs) capable of size shrinkage and charge conversion were developed and co-administered with iRGD to synergistically improve the intratumoral penetration and the anticancer efficacy. The NCs were constructed using the singlet oxygen-sensitive (SOS) polyethylene glycolpolyurethane-polyethylene glycol (PEG-(1O2)PU-PEG) triblock copolymer to encapsulate the doxorubicin (DOX)-loaded, chlorin e6 (Ce6)-conjugated polyamindoamine (PAMAM) dendrimer (DCD) via the double-emulsion method. Co-administration of iRGD notably increased the permeability of NCs within tumor vasculature and tumor tissues. In addition, upon far-red light irradiation (660 nm) of tumors at low optical density (10 mW/cm2), the generated 1O2 could disintegrate the NCs and release the DCD with positive surface charge and ultra-small size (∼5 nm), which synergized with iRGD to enable deep intratumoral penetration. Consequently, the local 1O2 at lethal concentrations along with the released DOX efficiently and cooperatively eradicated tumor cells. This study provides a convenient approach to spatiotemporally promote the intratumoral penetration of nanomedicine and mediate programmed anticancer therapy.

siRNA-mediated RNA interference (RNAi) against inflammation-related genes provides a promising modality for the treatment of myocardial ischemia reperfusion (IR) injury, and its success is critically dependent on the development of efficient yet safe siRNA delivery vehicles. Herein, we developed a bioreducible, branched poly(β-amino ester) with built-in redox-responsive domains (BPAE-SS) for the effective ICAM-1 siRNA delivery into injured rat cardiac microvascular endothelial cells (RCMECs). The branched BPAE-SS with a multivalent structure afforded potent siRNA binding affinity compared to its linear analogue, while upon internalization into RCMECs it was instantaneously degraded by intracellular glutathione (GSH) into small segments to mediate "on-demand" siRNA release and diminish the toxicity of post-transfection materials. By synchronizingly overcoming these critical barriers, BPAE-SS mediated remarkable ICAM-1 knockdown in IR-injured rats at 400 μg siRNA per kg via single i.v. injection, and subsequently suppressed myocardial inflammation, apoptosis, and fibrosis to recover the cardiac function. This study therefore provides a unique delivery system that can address the multiple critical challenges against non-viral siRNA delivery, and the potent therapeutic efficacy of BPAE-SS-mediated ICAM-1 silencing provides a promising strategy for the anti-inflammatory treatment of myocardial IR injury.

Stimuli-responsive drug delivery has rendered promising utilities in cancer treatment. Nevertheless, cancer selectivity as well as sensitivity still remains critical challenges that would undermine the therapeutic efficacy of chemodrugs and cause undesired systemic toxicity. Herein, a dual hypoxia-responsive drug delivery system was developed to enable photodynamic therapy (PDT)-induced drug release and drug activation intermediated via PDT-induced hypoxia. Particularly, tumor-targeting and hypoxia-dissociable nanoparticles (NPs) were self-assembled from the amphiphilic polyethylenimine-alkyl nitroimidazole [PEI-ANL (PA)] and hyaluronic acid-chlorin e6 (HA-Ce6) to encapsulate bioreductive chemodrug, tirapazamine (TPZ). After systemic administration, the obtained PA/HA-Ce6@TPZ NPs enabled effective tumor accumulation due to HA-mediated cancer targeting. Upon receptor-mediated endocytosis, light irradiation (660 nm, 10 mW/cm(2)) produced high levels of reactive oxygen species to mediate PDT and generated a severe local hypoxic environment to dissociate the NPs and selectively release TPZ, as a consequence of hypoxia-triggered hydrophobic-to-hydrophilic transformation of ANI. In the meantime, TPZ was activated under hypoxia, finally contributing to a synergistic anticancer treatment between PDT and hypoxia-strengthened bioreductive chemotherapy. This study, therefore, demonstrates a suitable strategy for cancer-selective drug delivery as well as programmed combination therapy.

Systemic immunosuppression mediated by tumor-derived exosomes is an important cause for the resistance of immune checkpoint blockade (ICB) therapy. Herein, self-adaptive platelet (PLT) pharmacytes are engineered to mediate cascaded delivery of exosome-inhibiting siRNA and anti-PD-L1 (aPDL1) toward synergized antitumor immunity. In the pharmacytes, polycationic nanocomplexes (NCs) assembled from Rab27 siRNA (siRab) and a membrane-penetrating polypeptide are encapsulated inside the open canalicular system of PLTs, and cytotoxic T lymphocytes (CTLs)-responsive aPDL1 nanogels (NGs) are covalently backpacked on the PLT surface. Upon systemic administration, the pharmacytes enable prolonged blood circulation and active accumulation to tumors, wherein PLTs are activated to liberate siRab NCs, which efficiently transfect tumor cells, silence Rab27a, and inhibit exosome secretion. The immunosuppression is thus relieved, leading to the activation, proliferation, and tumoral infiltration of cytotoxic T cells, which trigger latent aPDL1 release. As such, the competitive aPDL1 exhaustion by PD-L1-expressing exosomes is minimized to sensitize ICB. Synergistically, siRab and aPDL1 induce strong antitumor immunological response and memory against syngeneic murine melanoma. This study reports a bioinspired mechanism to resolve the blood circulation/cell internalization contradiction of polycationic siRNA delivery systems, and renders an enlightened approach for the spatiotemporal enhancement of antitumor immunity.

Oxygen reduction reaction (ORR) is one of the most important reactions in practical electrochemical energy devices such as fuel cells and metal-air batteries. In this paper, the recent advancements in platinum-group-metals-based alloys including Pt and/or Pd alloys with the late transitional metals for ORR electrocatalysis are reviewed in terms of catalyst synthesis, characterization, functional mechanism and the validation of performance (activities and stabilities) in both acidic and alkaline electrolytes. The electronic tuning and structural design/engineering for inducing lattice strain, favorable coordination environment, defects, vacancies, etc. for catalytic ORR active sites are emphasized. Morphologically, zero- to three-dimensional ORR catalysts with remarkable performances are introduced. For facilitating further research and development, several challenges are analyzed and the corresponding research directions for overcoming the challenges are also proposed.

The performance of non-viral gene delivery vehicles, especially cationic polymers, is often challenged by the multiple cellular barriers that pose inconsistent requirements for material properties. A most pronounced inconsistency is exemplified by the molecular weight (MW)-related transfection efficiency and cytotoxicity. In this study, we report the development of photo-degradable, branched poly(β-amino ester)s (BPAE-NB) to realize efficient and photo-controlled DNA and siRNA delivery. BPAE-NB possessing built-in light-responsive 2-nitrobenzene moieties in the polymer backbone was synthesized via the A2 (amine) + B3 (triacrylate) + C2 (diacrylate) polycondensation reaction from 4-amino-1-butanol (A2), trimethylolpropane triacrylate (B3), and (2-nitro-1,3-phenylene)bis(methylene) diacrylate (NPBMDA, C2). The highly branched BPAE-NB with the multivalent arrangement of cationic groups provides stronger nucleic acid binding capacity than its linear analogue LPAE-NB, and thus features stronger trans-membrane gene delivery capabilities and higher transfection efficiencies. Upon UV light irradiation, the backbone of BPAE-NB can quickly degrade into low-MW fragments as a consequence of the cleavage of the light-responsive 2-nitrobenzene, thus promoting intracellular gene release and diminishing the toxicity of materials at the post-transfection state. As such, in multiple mammalian cells, BPAE-NB exhibited remarkably higher DNA/siRNA transfection efficiency yet lower cytotoxicity than its non-responsive analogue BPAE-CC upon light irradiation, notably outperforming commercial reagents PEI 25k and Lipofectamine 2000. This study therefore provides an effective topology- and photo-controlled approach to precisely manipulate the transfection efficiency and toxicity of polycationic gene vectors, and may also provide promising additions to the existing non-viral gene delivery vectors.

Cisplatin remains the most effective therapy for non-small cell lung cancer (NSCLC). We previously have found cisplatin-resistant lung cancer cells (A549CisR and H157CisR) were more resistant to natural killer (NK) cell-mediated cytotoxicity than parental cells. We also discovered that fatty acid synthase (FASN) levels in cisplatin-resistant cells were significantly higher than in parental cells. To reveal whether a link exists between the up-regulated FASN levels and higher resistance to NK cell cytotoxicity, we performed inhibition studies using a FASN inhibitor and applied the FASN knockdown approach. In both approaches, we found that the FASN inhibition/knockdown significantly increased the susceptibility of cisplatin-resistant cells to NK cell cytotoxicity. We further found such decreased susceptibility was associated with an increased programmed death receptor ligand (PD-L1) level in cisplatin-resistant cells. In mechanisms studies, TGF-β1 was found to be the FASN downstream signaling molecule that was responsible for modulating the PD-L1 levels in cisplatin-resistant cells. Accordingly, TGF-β1 inhibition resulted in significantly increased susceptibility of cisplatin-resistant cells to NK cell cytotoxicity. We suggest that the inhibition of FASN-TGFβ1-PD-L1 axis may improve the efficacy of immunotherapy in treating cisplatin-resistant lung cancer.

Background Obesity affects prostate cancer (PCa) progression, and the periprostatic adipose tissue adjacent to the prostate is considered a driving force of disease progression. Adipocytes are the main cell population in adipose tissues and their paracrine role contributes to PCa progression, however its implication in modulating immune reactions remains largely unknown. We investigated the adipocyte role in controlling the susceptibility of castration-resistant PCa (CRPC) cells to the cytotoxic action of natural killer (NK) cells. Methods Using primary NK cells as the NK cell source, NK cell cytotoxicities to CRPC cells, either control media treated or adipocyte-conditioned media (CM) treated, were tested in lactate dehydrogenase (LDH) release-based assays. The levels of programmed death receptor ligand (PD-L1) and NK group 2D (NKG2D) ligands in adipocyte CM-treated CRPC cells were analyzed in qPCR analyses. Effects of blocking adipocyte action on altering PD-L1/NKG2D ligand levels and the susceptibility of CRPC cells to NK cell cytotoxicity were investigated. Results We found NK cell cytotoxicity to CRPC cells decreases when tumor cells are treated with adipocyte CM associated with PD-L1 and NKG2D ligand level alterations. Further, we discovered that the JAK/Stat3 signaling pathway was responsible for the adipocyte CM effect. Two adipokine molecules, IL-6 and leptin, were shown to be important in activation of the JAK/Stat3 signaling in CRPC cells to modulate the PD-L1/NKG2D ligand level alteration. Adding the inhibitors of JAK/Stat3 signaling or neutralizing antibodies of IL-6 or leptin increased the susceptibility of CRPC cells to NK cell action. Conclusions Blocking the adipocyte effect by inhibiting the IL-6/leptin-JAK/Stat3 signaling axis may enhance NK cell mediated immunity to CRPC cells and this strategy may help to develop future therapeutics to treat obese PCa patients.

Drug resistance diminishes the efficacies of anticancer therapeutics and causes the failure of clinical cancer chemotherapy. Herein, we reported a promising strategy to reverse drug resistance via RNA interference (RNAi)-assisted intervention of cancer bioenergetics. Densely packed, guanidine-rich, spherical helical polypeptide (DPP) was developed to encapsulate doxorubicin (DOX) inside its hydrophobic cavity and form polyelectrolyte nanocomplexes (NCs) with PKM2 siRNA. The NCs were further surface-decorated with hyaluronic acid (HA) to enhance the serum stability and promote tumor targeting via binding to over-expressed CD44 on cancer cell membranes. DPP with multivalent topology mediated potent trans-membrane delivery of PKM2 siRNA into DOX-resistance cancer cells. PKM2 down-regulation suppressed the glycolysis metabolism and depleted energy supply for ATP-binding cassette (ABC) transporters, thus inhibiting drug efflux to reverse drug resistance. Meanwhile, PKM2 silencing starved tumor cells, induced intracellular reactive oxygen species (ROS) generation, and triggered mitochondrial collapse, which aggravated cell apoptosis to achieve potent and cooperative anti-cancer effect with chemotherapy. This study thus provides an effective topology-controlled approach for designing trans-membrane siRNA delivery vehicles, and it also renders a promising tool in rejuvenating chemotherapy against drug-resistant tumors via a unique anti-bioenergetics mechanism.

In this study, in order to investigate the effects of increased macrophage infiltration to radioresistant lung tumors in regulating natural killer (NK) cell-mediated immunity, we examined whether the treatment of radioresistant cells with conditioned medium (CM) from phorbol myristate acetate (PMA)/interleukin (IL)-4 treated THP-1 cells (used as a tumor-associated macrophage source) leads to the development of the additional resistance of tumor cells to NK cell cytotoxicity. We found that the susceptibility of THP-1 CM-treated radioresistant cells to NK cell cytotoxicity was decreased compared to the non-treated cells. In addition, it was found that such a decreased susceptibility was associated with increased programmed death receptor ligand 1 (PD-L1) and decreased natural killer group 2D (NKG2D) ligand levels in tumor cells. We further discovered that the THP-1 cells secreted a high level of IL-6, and that blocking IL-6 action by the addition of a neutralizing antibody (Ab) for IL-6 into the THP-1 CM decreased the resistance of THP-1 CM-treated radioresistant cells to NK cell cytotoxicity. Moreover, we discovered that MEK/Erk was the most critical IL-6 downstream signaling pathway in triggering the THP-1 CM effect; thus, the addition of MEK/Erk inhibitor to THP-1 CM enhanced the susceptibility of the THP-1 CM-treated radioresistant cells to NK cell cytotoxicity. On the whole, the findings of this study suggest the existence of a malignant loop characterized by increased macrophage infiltration into radioresistant cells which, in turn, promotes the development of the additional resistance of these cells to NK cell cytotoxicity.

Purpose/Objective(s): Treatments for superior sulcus non-small cell lung cancer (SS-NSCLC) have evolved, but adequate treatments of T4 disease have not been found. The aim of our study was to evaluate the prognostic factors and optimal treatment strategy for patients with T4 SS-NSCLC. Materials/Methods: We utilized the Surveillance, Epidemiology, and End Results (SEER) database (1973–2015) to identify patients diagnosed with T4 stage SS-NSCLC (according to the 7th edition American Joint Committee on Cancer (AJCC) staging system) from 2004 to 2015; those with M1 disease were excluded. Propensity score matching (PSM) with Kaplan–Meier and Cox proportional hazards’ models was performed to estimate prognosis. Results: A total of 384 patients were included. The majority was male (59.4%) at stage IIIB (56.6%), with N2 accounting for 45.3%. A total of 47 patients underwent cancer-directed surgery, while radiotherapy alone was received by 60.2% of patients. Median overall survival (OS) and lung cancer-specific survival (LCSS) were 12 and 17 months, respectively, and the 5-year OS and LCSS rates were 15.8 and 25.4%, respectively. In the matched population, the median survival outcomes were better following surgery (OS: 25 compared with 9.0 months, P

Background: Erlotinib (ELTN)-based targeted therapy as first-line treatment for epidermal growth factor receptor (EGFR)-mutant lung cancers suffers from insufficient selectivity, side effects, and drug resistance, which poses critical challenges in the clinical setting. Acquired resistance of ELTN results in extremely poor prognoses of non-small cell lung cancer (NSCLC) patients, wherein activation of the JAK2/STAT3 signaling pathway has been proven to induce acquired ELTN resistance.Methods: In this study, we developed a nanoparticle (NP) delivery system based on Food and Drug Administration (FDA)-approved poly(ethylene glycol) (PEG)-poly(lactic acid) (PLA) for the co-delivery of ELTN and fedratinib (FDTN, a small-molecular, highly selective JAK2 inhibitor). Both ELTN and FDTN could be encapsulated into the PEG-PLA NPs via optimization of the encapsulation method. The effect of NPs on NSCLC cells was evaluated by MTT assay. Western blotting was performed to study the molecular mechanisms of NPs inhibiting the downstream pathways of EGFR in vitro. The histological analysis and protein expression in vivo were assessed by hematoxylin/eosin (H&E) staining and immunohistochemistry, respectively.Results: The drug cargoes exhibited great stability, and could be released more efficiently in the acidic tumorous condition. Mechanistic study showed that FDTN notably down-regulated the expression levels of proteins in the JAK2/STAT3 signaling pathway, including p-EGFR, p-JAK2, p-STAT3 and Survivin, therefore reversing the ELTN resistance. As a result, synergistic anti-cancer effect was achieved by PEG-PLA NPs encapsulating both ELTN and FDTN in ELTN-resistant NSCLC tumors both in vitro and in vivo, and lower systemic side effect was noted for the co-delivery NPs compared to free drugs.Conclusion: This study provides a promising approach to overcome the ELTN resistance in the treatment of NSCLC, and the use of FDA-approved materials with clinically applied/investigated chemical drugs may facilitate the translation of the current delivery system.

Cisplatin-resistant (A549CisR and H292CisR) and radioresistant (A549R26 and H292R22) sub-line non-small cell lung cancer (NSCLC) cells were developed in our lab by long term treatment of parental cells with cisplatin or radiation. Our data showed no cross-resistance between these two sets of cell lines, indicating that molecular mechanisms of developing each resistance may be different. Using these sub-line cells, we sought to reveal the most significantly up-regulated molecules in cisplatin-resistant and radioresistant lung cancer cells, compared with parental cells. In qPCR analyses of screening DNA repair and cell survival-associated molecules, we identified NFκB and TNFα as the most significantly up-regulated molecules in cisplatin-resistant and radioresistant lung cancer cells, respectively, compared with parental cells. Western blot analysis of parental vs. resistant cells and the IHC staining of tumor tissues of A549P, A549CisR, and A549R26 cell-derived xenografts in mice confirmed such results. Next, studies using specific inhibitors of NFκB and TNFα and experiments using NFκB and TNFα-knocked down cells showed that inhibition or knockdown of NFκB overcame cisplatin-resistance, while inhibition or knockdown of TNFα increased radiosensitivity of radioresistant lung cancer cells. Therefore, these two molecules may be used as markers of the prognosis/diagnosis of individual resistance development during lung cancer treatment.

As one of the intractable challenges in the clinic, the treatment of acute liver failure (ALF) is limited due to high mortality and resource cost. RNA interference (RNAi) provides a new modality for the anti-inflammatory therapy of ALF, while its therapeutic efficacy is greatly hampered by the lack of effective carriers to cooperatively overcome the various systemic barriers. Herein, we developed macrophage-targeting and reactive oxygen species (ROS)-responsive polyplexes to enable efficient systemic delivery of TNF-α siRNA (siTNF-α) to attenuate hepatic inflammation in mice bearing ALF. Se-PEI, obtained from the cross-linking of 600 Da polyethylenimine (PEI) via the ROS-responsive diselenide bond, was developed to condense siTNF-α, and the obtained polyplexes were further coated with carboxylated mannan (Man-COOH). Man-COOH coating allowed active targeting of polyplexes to macrophages with over-expressed mannose receptors (MRs), and it shielded the surface positive charges to enhance the serum stability of polyplexes. Se-PEI could be degraded by ROS in inflammatory macrophages to promote intracellular siRNA release to potentiate the gene knockdown efficiency, and in the meantime reduce the material cytotoxicity associated with high molecular weight. As such, i.v. injected Man-COOH/Se-PEI/siTNF-α polyplexes afforded notable TNF-α silencing by ∼80% in inflamed liver tissues at 500 μg siRNA per kg, and notably reduced serum TNF-α levels to achieve potent anti-inflammatory performance against ALF.

Radiation treatment induces neuroendocrine differentiation (NED) in non-small cell lung cancer (NSCLC) A549 and H157 cells, so higher NE-like features in radioresistant A549 (A549R26-1) and H157 (H157R24-1) cells are observed than in parental cells. We detected higher NED marker expressions in A549R26-1 cell-derived tumors than in A549 cell-derived tumors. In mechanism studies, we found that NED induction in A549R26-1 and H157R24-1 cells was accompanied by increased intracellular cAMP and IL-6 levels. Treatment of radioresistant lung cancer cells with the inhibitor (SQ22536) of adenylate cyclase (AC) which is the enzyme responsible for the cAMP production, or the neutralizing antibody (Ab) of IL-6, resulted in decreased NE-like features in radioresistant lung cancer cells. In addition, we found MEK/Erk is the signaling pathway that triggers the cAMP- and IL-6-mediated NED induction in radioresistant lung cancer cells. Also, we found that MEK/Erk signaling pathway inhibition decreased NED in radioresistant cells. Radioresistant lung cancer cells exhibiting high NE-like features also showed higher radioresistance and higher metastatic potential than parental cells. When we inhibited cAMP-, or IL-6-mediated pathways, or the downstream MEK/Erk signaling pathway, radiosensitivity of radioresistant lung cancer cells was significantly increased and their metastatic potential was significantly reduced. In in vivo mouse studies, reducing NED by treating mice with the MEK/Erk inhibitor increased radiosensitivity. Immunohistochemical staining of tumor tissues lowered expressions of the NED/epithelial-mesenchymal transition (EMT)/metastatic markers when mice were treated with the MEK/Erk inhibitor.

The precise and selective delivery of chemodrugs into tumors represents a critical requirement for anti-cancer therapy. Intelligent delivery systems that are responsive to a single internal or external stimulus often lack sufficient cancer selectivity, which compromises the drug efficacy and induces undesired side effects. To overcome this dilemma, we herein report a cancer-targeting vehicle which allows highly cancer-selective drug release in response to cascaded external (light) and internal (hypoxia) dual triggers. In particular, doxorubicin (DOX)-loaded, hypoxia-dissociable nanoparticles (NPs) were prepared from self-assembled polyethylenimine-nitroimidazole (PEI-NI) micelles that were further co-assembled with hyaluronic acid-Ce6 (HC). Upon accumulation in tumor cells, tumor site-specific light irradiation (660 nm, 10 mW cm−2) generated high levels of reactive oxygen species (ROS) and greatly enhanced the hypoxic levels to induce NP dissociation and accordingly DOX release. A synergistic anti-cancer efficacy between DOX-mediated chemotherapy and Ce6-mediated photodynamic therapy (PDT) was thus achieved, resulting in reduced side effects to normal tissues/cells. This study therefore provides an effective method to control the cancer-specific drug delivery by responding to cascaded multiple triggers, and it renders promising applications for the programmed combination of chemotherapy and PDT toward cancer treatment.

Background: We previously reported that IL-6 was associated with therapy resistance to radiotherapy and cisplatin chemotherapy, the two most common treatments for non-small cell lung cancer (NSCLC). Emerging in vivo evidence shows that natural killer (NK) cells have an important role in immune defense. In this study, we examined the role of IL-6 modulation in lung cancer PD-L1 expression and the impact on NK cell cytotoxicity. We also revealed the key molecular signaling pathway involved in this process, which serves as the potential therapeutic target to improve clinical lung cancer treatments. Methods: We examined the prevalence of IL-6 in tumors of NSCLC in immunohistochemical staining. The susceptibility of IL-6 expressing scramble control (A549sc and H157sc) cells and IL-6 knocked down (A549siIL-6 and H157siIL-6) cells were investigated in in vitro and in vivo human tumor xenograft studies in mice. In in vivostudies, tumors were developed by luciferase tagged A549siIL-6 vs. A549sc cell injection, and primary human NK cells were injected intravenously at the early stage of tumor development. IL-6 regulation of PD-L1 at the transcriptional level was investigated and NK cell binding to tumor cells was also examined. Results: We found the ubiquitous presence of IL-6 in NSCLC. We found IL-6 expressing lung cancer cells were more resistant to NK cell cytotoxicity than IL-6 knocked-down cells. In addition, we found higher expressions of programmed death receptor 1 ligand (PD-L1) in IL-6 expressing lung cancer cells than IL-6 knocked-down cells. In excised human tumor xenografts and in human NSCLC tumors, co-localization of IL-6 signaling and PD-L1 expression was observed. Furthermore, we discovered that IL-6 promoted PD-L1 expression at the transcriptional level via the regulation of its downstream MEK/Erk signaling pathway. In addition, we found that IL-6-MEK/Erk signaling also contributed to diverting NK cells away from binding to tumor cells. Conclusions and Impact: In conclusion, we found that IL-6 develops the resistance to NK cell actions by inducing PD-L1 in NSCLC cells and diverts NK cells away from tumor cells via its downstream MEK/Erk signaling. NK cell-mediated immune function plays an important role in cancer surveillance, invasion, and metastasis, but its role in lung cancer is not clear. In in vivo studies, we proved the importance of NK cell-mediated immune reaction. Our discovery of revealing the IL-6 downstream signaling, MEK/Erk, in triggering the PD-L1 up-regulation and in blocking NK cell binding with lung cancer cells is novel. Data from this investigation support that blocking MEK/Erk signaling pathway has the potential to enhance NK cell immune function to NSCLC by overcoming IL-6 mediated NK cell resistance. Citation Format: Soo Ok Lee, Rongying Zhu, Xiang Xue, Donglai Cchen, Shanzhou Duan, Mingjing Shen, Feng Chen, Ying Tsai, Peter Keng, Yongbing Chen, Yuhchyau chen. IL-6 up-regulates pd-l1 and facilitates lung cancer escape from NK cell immune function through its downstream MEK-ERK signaling [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1520.

Background Metastasis to regional lymph nodes represents the first step of dissemination in esophageal cancer and serves as an unfavorable prognostic indicator for disease progression. The formation of tumor lymphatic microvessels is dependent on the production of lymphangiogenic growth factors by tumor cells, such as vascular endothelial growth factor C (VEGF-C), metastasis-associated gene 1 (MTA1), and hypoxia inducible-factor l alpha (HIF-1α). The degree of intratumoral lymphatic microvessel density (LMVD) by immunohistochemistry is thought to influence tumor lymph node metastasis (LNM) and prognosis in various solid tumors. The aim of this study was to investigate the expression of MTA1 and HIF-1α in human esophageal cancer and to explore the relationship between their expression and lymphangiogenesis. Method The expression of MTA1 and HIF-1α, and LMVD marked by D2-40 were detected using immunohistochemical staining in eighty-two human esophageal cancer cases. Results The positive rates of MTA1 and HIF-1α expression were 69.5% and 59.8%, respectively. The expression of MTA1 and HIF-1α were both correlated with LNM. In addition, MTA1 and HIF-1α expression has a positive correlation in human esophageal cancer; LMVD correlated significantly with LNM. LMVD in MTA1 and HIF-1α over-expression cases was higher than that in none or weak cases, and this difference has statistical significance. Conclusion Our findings suggest that MTA1 plays an important role in lymphangiogenesis and LNM by stabilizing HIF-1α in esophageal cancer. The inhibition of lymphangiogenesis, MTA1, or HIF-1α activity may have an important therapeutic benefit in the control of esophageal cancer.

Background: One-third of US population is obese. The mortality of obese prostate cancer (PCa) patients is higher than non-obese patients, thus studying molecular mechanism of how obesity affects PCa progression has clinical relevance. The periprostatic adipose tissue adjacent to the prostate is considered a driving force of disease progression and adipocytes are the main cell population in adipose tissues. The paracrine role of adipocytes in PCa progression has been emphasized, but its implication in modulating immune reactions remains unknown. We investigated the role of adipocytes in the surveillance of castration-resistant PCa (CRPC) cells to immune actions. Especially we investigated the role of adipocytes in affecting tumor cell susceptibility to cytotoxic action of natural killer (NK) cells, as the strategy of improving the NK cell-mediated immunity is emerging as an immunotherapeutic option. Methods: Using primary NK cells as the NK cell source, NK cell cytotoxicities to CRPC cells, either control media treated or adipocyte-conditioned media (CM) treated, were tested in lactate dehydrogenase (LDH) release-based assays. The levels of programmed death receptor ligand (PD-L1) and NK group 2D (NKG2D) ligands in adipocyte CM-treated CRPC cells were analyzed in qPCR analyses. Effects of blocking adipocyte action on altering PD-L1/NKG2D ligand levels and the susceptibility of CRPC cells to NK cell cytotoxicity were investigated. Results: We found NK cell cytotoxicity to CRPC cells decreased when tumor cells were treated with adipocyte CM, and was associated with PD-L1 (up-regulation) and NKG2D ligand level (down-regulation) alterations. Further, we discovered that the JAK/Stat3 signaling pathway was activated by adipocyte CM. Two adipokine molecules, IL-6 and leptin, were shown to be important in the activation of the JAK/Stat3 signaling to modulate the PD-L1/NKG2D ligand level alterations in CRPC cells. Consequently, adding inhibitors of JAK/Stat3 signaling or neutralizing antibodies of IL-6 or leptin increased the susceptibility of CRPC cells to NK cell cytotoxic action. Conclusions and Impact: Results from our study showed the influence of adipocytes on tumor cells and resulted in reducing the susceptibility to NK cell-mediated antitumor immune function. This may be one of ways that adipocytes trigger CRPC cells to be more aggressive and out of immune surveillance control. Our study results showed that blocking the adipocyte effect by inhibiting the IL-6/leptin-JAK/Stat3 signaling axis enhanced the NK cell mediated immunity to CRPC cells. We suggest that this strategy can be applied to the development of future immune therapeutics to treat obese PCa patients. Citation Format: Lijun Xu, Mingjing Shen, Xiaodong Chen, Rongying Zhu, Dong-rong Yang, Ying Tsai, Peter Keng, Yuhchyau Chen, Soo Ok Lee. Adipocytes affect castration-resistant prostate cancer cells in resistance to cytotoxic action of NK cells through alterations of pd-l1/nkg2d ligand levels [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3147.

XAF1 is a factor necessary to inhibit tumor cell growth. Low XAF1 expression is associated with various tumor cells. The aim of this study is to investigate the effect and the mechanism of adenovirus vector Ad5/F35 mediated X-linked inhibitor of apoptosis protein associated factor-1 (XAF1) on the inhibition of cell proliferation and the induction of apoptosis of human lung adenocarcinoma cell A549.Recombinant virus Ad5/F35-XAF1 and controlled virus Ad5/F35-NULL exhibited different multiplicities of infection (MOI) at the same time. mRNA and protein expressions of XAF1 were determined by reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot, respectively. Cell proliferation was observed by methyl thiazolyl tetrazolium (MTT) assay, and cell apoptosis was analyzed by FACS with Annexin V-FITC/PI double staining. The expressions of apoptosis-associated proteins, such as PARP, Caspase-3, and Caspase-8, were also determined by Western blot.mRNA and protein expressions of XAF1 were significantly increased in human lung adenocarcinoma cell A549 after this cell was transfected with Ad5/F35-XAF1 for 48 h; these expressions were higher than those of the controlled group Ad5/F35-NULL. Cell proliferation was inhibited and apoptosis was induced in a dose-dependent manner in the Ad5/F35-XAF1 group. After Ad5/F35-XAF1 transfection was performed, the cleavage of apoptosis-associated proteins, such as PARP, Caspase-3, and Caspase-8, was activated.Restored XAF1 expression inhibits cell proliferation and induces cell apoptosis in human lung adenocarcinoma cell line A549. Furthermore, XAF1 may activate associated apoptotic signaling pathways in A549 cell line.背景与目的 XAF1是重要的肿瘤细胞生长抑制因子，其低表达与多种肿瘤细胞有关。研究肿瘤抑制基因XAF1对人肺腺癌细胞株A549的作用及机制。方法 利用重组腺病毒Ad5/F35-XAF1和对照腺病毒Ad5/F35-NULL瞬时转染A549细胞，用逆转录聚合酶链式反应（reverse transcriptase polymerase chain reaction, RT-PCR）和Western blot方法检测A549细胞株中XAF1 mRNA和蛋白质的表达；MTT检测细胞增殖率、流式细胞仪检测细胞凋亡率，并用Western blot法检测凋亡相关蛋白的表达。结果 腺病毒介导的XAF1瞬时转染肺腺癌A549细胞后，XAF1 mRNA及蛋白表达水平明显提高，并能明显抑制该细胞增殖和促进细胞凋亡，蛋白质印记法显示凋亡相关蛋白PARP、Caspase-3、Caspase-8的裂解条带。结论 恢复XAF1基因在人肺腺癌A549细胞中表达后，能明显抑制该肿瘤细胞增殖并促进其凋亡，其机制可能与XAF1激活肺癌细胞相关凋亡途径有关。

Non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutations are responsive to EGFR-tyrosine kinase inhibitor (EGFR-TKI). However, NSCLC patients with secondary somatic EGFR mutations are resistant to EGFR-TKI treatment. In this study, we investigated the effect of TG101348 (a JAK2 inhibitor) on the tumor growth of erlotinib-resistant NSCLC cells. Cell proliferation, apoptosis, gene expression and tumor growth were evaluated by diphenyltetrazolium bromide (MTT) assay, flow cytometry, terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling (TUNEL) staining, Western Blot and a xenograft mouse model, respectively. Results showed that erlotinib had a stronger impact on the induction of apoptosis in erlotinib-sensitive PC-9 cells but had a weaker effect on erlotinib-resistant H1975 and H1650 cells than TG101348. TG101348 significantly enhanced the cytotoxicity of erlotinib to erlotinib-resistant NSCLC cells, stimulated erlotinib-induced apoptosis and downregulated the expressions of EGFR, p-EGFR, p-STAT3, Bcl-xL and survivin in erlotinib-resistant NSCLC cells. Moreover, the combined treatment of TG101348 and erlotinib induced apoptosis, inhibited the activation of p-EGFR and p-STAT3, and inhibited tumor growth of erlotinib-resistant NSCLC cells in vivo. Our results indicate that TG101348 is a potential adjuvant for NSCLC patients during erlotinib treatment.

Metastasis to regional lymph nodes represents the first step of dissemination in esophageal cancer and serves as an unfavorable prognostic indicator for disease progression. The formation of tumor lymphatic microvessels is dependent on the production of lymphangiogenic growth factors by tumor cells, such as vascular endothelial growth factor C (VEGF-C), metastasis-associated gene 1 (MTA1), and hypoxia inducible-factor l alpha (HIF-1α). The degree of intratumoral lymphatic microvessel density (LMVD) by immunohistochemistry is thought to influence tumor lymph node metastasis (LNM) and prognosis in various solid tumors. The aim of this study was to investigate the expression of MTA1 and HIF-1α in human esophageal cancer and to explore the relationship between their expression and lymphangiogenesis.The expression of MTA1 and HIF-1α, and LMVD marked by D2-40 were detected using immunohistochemical staining in eighty-two human esophageal cancer cases.The positive rates of MTA1 and HIF-1α expression were 69.5% and 59.8%, respectively. The expression of MTA1 and HIF-1α were both correlated with LNM. In addition, MTA1 and HIF-1α expression has a positive correlation in human esophageal cancer; LMVD correlated significantly with LNM. LMVD in MTA1 and HIF-1α over-expression cases was higher than that in none or weak cases, and this difference has statistical significance.Our findings suggest that MTA1 plays an important role in lymphangiogenesis and LNM by stabilizing HIF-1α in esophageal cancer. The inhibition of lymphangiogenesis, MTA1, or HIF-1α activity may have an important therapeutic benefit in the control of esophageal cancer.