BACKGROUND: In the current study, the authors sought to identify the molecular mechanisms underlying the chemoresistance of lung cancer stem or initiation cells (cancer stem cells). METHODS: A549 lung cancer cells before and after selective enrichment of a subpopulation of cancer stem cells were treated with superoxide and traditional chemotherapeutics to determine their sensitivity or resistance to these cytotoxic agents. Apoptotic activity was measured using a variety of fluorescence‐based and biochemical techniques. Specific pathways involved in the chemoresistance of cancer stem cell‐enriched lung cancer cells were analyzed with Western blotting and pharmacologic targeting therapy in a xenograft model. RESULTS: Lung cancer stem cells exhibited significantly decreased apoptotic response to treatment with superoxide, cisplatin, gemcitabine, or a combination of cisplatin and gemcitabine compared with control A549 cells. Apoptotic resistance was mediated through the inactivation of caspase‐9 and caspase‐3. Increased activation of p38MAPK, MAPKAPK2, and Hsp27 was observed in lung cancer stem cells compared with control A549 cells both before and after exposure to superoxide and chemotoxic agents. In a mouse model of lung cancer, chemotherapy‐induced cells increased in the antiapoptosis pathway, and quercetin, an inhibitor of Hsp27, combined with traditional chemotherapy was effective in blocking the pathway and in the treatment of lung tumors in vivo. CONCLUSIONS: The authors' data demonstrate that lung cancer stem cells have elevated levels of activated Hsp27 upon treatment with superoxide and traditional chemotherapy. When combined with chemotoxic agents, blockage of Hsp27 decreased the survival of lung cancer stem cells, which otherwise were resistant to traditional chemotherapy. Cancer 2011. © 2010 American Cancer Society.

BackgroundThymic epithelial tumors are PD-L1–expressing tumors of thymic epithelial origin characterized by varying degrees of lymphocytic infiltration and a predisposition towards development of paraneoplastic autoimmunity. PD-1–targeting antibodies have been evaluated, largely in patients with thymic carcinoma. We sought to evaluate the efficacy and safety of the anti-PD-L1 antibody, avelumab (MSB0010718C), in patients with relapsed, advanced thymic epithelial tumors and conduct correlative immunological studies.MethodsSeven patients with thymoma and one patient with thymic carcinoma were enrolled in a phase I, dose-escalation trial of avelumab (MSB0010718C), and treated with avelumab at doses of 10 mg/kg to 20 mg/kg every 2 weeks until disease progression or development of intolerable side effects. Tissue and blood immunological analyses were conducted.ResultsTwo of seven (29%) patients with thymoma had a confirmed Response Evaluation Criteria in Solid Tumors–defined partial response, two (29%) had an unconfirmed partial response and three patients (two thymoma; one thymic carcinoma) had stable disease (43%). Three of four responses were observed after a single dose of avelumab. All responders developed immune-related adverse events that resolved with immunosuppressive therapy. Only one of four patients without a clinical response developed immune-related adverse events. Responders had a higher absolute lymphocyte count, lower frequencies of B cells, regulatory T cells, conventional dendritic cells, and natural killer cells prior to therapy.ConclusionThese results demonstrate anti-tumor activity of PD-L1 inhibition in patients with relapsed thymoma accompanied by a high frequency of immune-related adverse events. Pre-treatment immune cell subset populations differ between responders and non-responders.Trial registrationClinicalTrials.gov - NCT01772004. Date of registration – January 21, 2013.Electronic supplementary materialThe online version of this article (10.1186/s40425-019-0723-9) contains supplementary material, which is available to authorized users.

We sought to determine the possible neural conduction blockade of tramadol and whether there is evidence of localized neural toxicity with spinal somatosensory evoked potential (SSEP) measurements. Male Wistar rats were used. SSEP, elicited by supramaximally stimulating the hind paw and recorded from the thoracolumbar and the first and second lumbar interspinous ligaments, was monitored. SSEPs were obtained before drug application as the pretreatment baseline and measured every 15 min after treatment for 2 h and at 60-min intervals thereafter until SSEP returned to baseline or for another 4 h. Two small strips of Gelfoam (0.6 x 1.0 cm(2)) soaked with the drug were placed under and over the left sciatic nerve for a 30-min period. Gelfoam was prepared with tramadol hydrochloride (Tramal; the US trade name is Ultram) 5, 2.5, and 1.25 mg, diluted if needed with saline to a total volume of 100 microL (5%, 2.5%, and 1.25%, respectively). The control data were obtained from the right side limb with normal saline by following the same method. Spinal SSEPs were measured after 48 h to detect the late neural damage. The results showed that direct tramadol application on sciatic nerves dose-dependently reduced both the amplitude and conduction velocity of SSEPs when compared with the pretreatment baseline. All SSEPs returned to pretreatment baseline, and no significant changes of SSEP between bilateral limbs were noted at the 48-h measurements. No evidence of irreversible conduction blockade indicative of local neural toxicity was seen. Pretreatment with naloxone 1 mg/kg failed to block the changes of SSEP produced by 2.5% tramadol 100 microL. We conclude that tramadol exerts a local anesthetic-type effect on peripheral nerves.

Automatic photo cropping is an important tool for improving visual quality of digital photos without resorting to tedious manual selection. Traditionally, photo cropping is accomplished by determining the best proposal window through visual quality assessment or saliency detection. In essence, the performance of an image cropper highly depends on the ability to correctly rank a number of visually similar proposal windows. Despite the ranking nature of automatic photo cropping, little attention has been paid to learning-to-rank algorithms in tackling such a problem. In this work, we conduct an extensive study on traditional approaches as well as ranking-based croppers trained on various image features. In addition, a new dataset consisting of high quality cropping and pairwise ranking annotations is presented to evaluate the performance of various baselines. The experimental results on the new dataset provide useful insights into the design of better photo cropping algorithms.

In yeast, Arl3p recruits Arl1p GTPase to regulate Golgi function and structure. However, the molecular mechanism involved in regulating activation of Arl1p at the Golgi is unknown. Here, we show that Syt1p promoted activation of Arl1p and recruitment of a golgin protein, Imh1p, to the Golgi. Deletion of SYT1 resulted in the majority of Arl1p being distributed diffusely throughout the cytosol. Overexpression of Syt1p increased Arl1p-GTP production in vivo and the Syt1-Sec7 domain promoted nucleotide exchange on Arl1p in vitro. Syt1p function required the N-terminal region, Sec7 and PH domains. Arl1p, but not Arl3p, interacted with Syt1p. Localization of Syt1p to the Golgi did not require Arl3p. Unlike arl1Δ or arl3Δ mutants, syt1Δ did not show defects in Gas1p transport, cell wall integrity or vacuolar structure. These findings reveal that activation of Arl1p is regulated in part by Syt1p, and imply that Arl1p activation, by using more than one GEF, exerts distinct biological activities at the Golgi compartment.

Purpose: Overexpression of DNA 5 0 -cytosine-methyltransferase 3A (DNMT3A), which silences genes including tumor suppressor genes (TSG), is involved in many cancers. Therefore, we examined whether the transcriptional deregulation of RB/MDM2 pathway was responsible for DNMT3A overexpression and analyzed the therapeutic potential of MDM2 antagonist for reversing aberrant DNA methylation status in lung cancer.Experimental Design: The regulation of DNMT3A expression and TSG methylation status by RB/MDM2 was assessed in cancer cell lines and patients. The effects of Nutlin-3, an MDM2 antagonist, on tumor growth in relation to DNMT3A expression and TSG methylation status were examined by xenograft model.Results: We found that RB suppressed DNMT3A promoter activity and mRNA/protein expression through binding with E2F1 protein to the DNMT3A promoter, leading to the decrease of methylation level globally and TSG specifically. In addition, MDM2 dramatically induced DNMT3A expression by negative control over RB. In clinical study, MDM2 overexpression inversely correlated with RB expression, while positively associating with overexpression of DNMT3A in samples from patients with lung cancer. Patients with high MDM2 and low RB expression showed DNMT3A overexpression with promoter hypermethylation in TSGs. Treatment with Nutlin-3, an MDM2 antagonist, significantly suppressed tumor growth and reduced DNA methylation level of TSGs through downregulation of DNMT3A expression in xenograft studies.Conclusions: This study provides the first cell, animal, and clinical evidence that DNMT3A is transcriptionally repressed, in part, by RB/E2F pathway and that the repression could be attenuated by MDM2 overexpression. MDM2 is a potent target for anticancer therapy to reverse aberrant epigenetic status in cancers.

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miRNA cluster miR-17-92 is known as oncomir-1 due to its potent oncogenic function. miR-17-92 is a polycistronic cluster that encodes 6 miRNAs, and can both facilitate and inhibit cell proliferation. Known targets of miRNAs encoded by this cluster are largely regulators of cell cycle progression and apoptosis. Here, we show that miRNAs encoded by this cluster and sharing the seed sequence of miR-17 exert their influence on one of the most essential cellular processes – endocytic trafficking. By mRNA expression analysis we identified that regulation of endocytic trafficking by miR-17 can potentially be achieved by targeting of a number of trafficking regulators. We have thoroughly validated TBC1D2/Armus, a GAP of Rab7 GTPase, as a novel target of miR-17. Our study reveals regulation of endocytic trafficking as a novel function of miR-17, which might act cooperatively with other functions of miR-17 and related miRNAs in health and disease.