Oxidized low density lipoprotein inhibits interleukin-12 production in lipopolysaccharide-activated mouse macrophages via direct interactions between peroxisome proliferator-activated receptor-gamma and nuclear factor-kappa B

Lipopolysaccharide (LPS) increases the production of interleukin-12 (IL-12) from mouse macrophages via a kappaB site within the IL-12 p40 promoter. In this study, we found that oxidized low density lipoprotein (oxLDL) inhibited this LPS-stimulated production of IL-12 in a dose-dependent manner while native LDL did not. OxLDL inhibited p40 promoter activation in monocytic RAW264.7 cells transiently transfected with p40 promoter/reporter constructs, and the repressive effect mapped to a region in the p40 promoter containing a binding site for nuclear factor-kappaB (NF-kappaB) (p40-kappaB). Activation of macrophages by LPS in the presence of oxLDL resulted in markedly reduced binding to the kappaB site, as demonstrated by the electrophoretic mobility shift assays. In contrast, native LDL did not inhibit the IL-12 p40 promoter activation and NF-kappaB binding to the kappaB sites, suggesting that oxidative modification of LDL was crucial for the inhibition of NF-kappaB-mediated IL-12 production. 9-Hydroxyoctadecadienoic acid, a major oxidized lipid component of oxLDL, significantly inhibited IL-12 production in LPS-stimulated mouse macrophages and also suppressed NF-kappaB-mediated activation in IL-12 p40 promoter. The NF-kappaB components p50 and p65 directly bound peroxisome proliferator-activated receptor-gamma (PPAR-gamma) in vitro. In cotransfections of CV-1 and HeLa cells, PPAR-gamma inhibited the NF-kappaB transactivation in an oxLDL-dependent manner. From these results, we propose that oxLDL-mediated suppression of the IL-12 production from LPS-activated mouse macrophages may, at least in part, involve both inhibition of the NF-kappaB-DNA interactions and physical interactions between NF-kappaB and PPAR-gamma.

Key chemokines direct migration of immune cells in solid tumors

Immune cell infiltration into solid tumors, their movement within the tumor microenvironment (TME), and interaction with other immune cells are controlled by their directed migration towards gradients of chemokines. Dysregulated chemokine signaling in TME favors the growth of tumors, exclusion of effector immune cells, and abundance of immunosuppressive cells. Key chemokines directing the migration of immune cells into tumor tissue have been identified. In this review, we discuss well-studied chemokine receptors that regulate migration of effector and immunosuppressive immune cells in the context of cancer immunology. We discuss preclinical models that have described the role of respective chemokine receptors in immune cell migration into TME and review preclinical and clinical studies that target chemokine signaling as standalone or combination therapies.

Retinoids inhibit interleukin-12 production in macrophages through physical associations of retinoid X receptor and NFkappaB

Lipopolysaccharide (LPS) increases the production of interleukin-12 (IL-12) from mouse macrophages via a kappaB site within the IL-12 p40 promoter. In this study, we found that retinoids inhibit this LPS-stimulated production of IL-12 in a dose-dependent manner. The NFkappaB components p50 and p65 bound retinoid X receptor (RXR) in a ligand-independent manner in vitro, and the interaction interfaces involved the p50 residues 1-245, the p65 residues 194-441, and the N-terminal A/B/C domains of RXR. Activation of macrophages by LPS resulted in markedly enhanced binding activities to the kappaB site, which significantly decreased upon addition of retinoids, as demonstrated by the electrophoretic mobility shift assays. In cotransfections of CV-1 and HeLa cells, RXR also inhibited the NFkappaB transactivation in a ligand-dependent manner, whereas a mutant RXR lacking the AF2 transactivation domain, which serves as ligand-dependent binding sites for transcription integrators SRC-1 and p300, was without any effect. In addition, coexpression of increasing amounts of SRC-1 or p300 relieved the retinoid-mediated inhibition of the NFkappaB transactivation. From these results, we propose that retinoid-mediated suppression of the IL-12 production from LPS-activated macrophages may involve both inhibition of the NFkappaB-DNA interactions and competitive recruitment of transcription integrators between NFkappaB and RXR.

Histologic Analysis of Retrieved Clots in Acute Ischemic Stroke: Correlation with Stroke Etiology and Gradient-Echo MRI

BACKGROUND AND PURPOSE

It is unclear whether clot composition analysis is helpful to predict a stroke mechanism in acute large vessel occlusion. In addition, the relationship between early vessel signs on imaging studies and clot compositions has been poorly understood. The purpose of this study was to elucidate the relationship between clot composition and stroke etiology following mechanical thrombectomy and to investigate the effect of varied clot compositions on gradient-echo MR imaging of clots.

MATERIALS AND METHODS

Histopathologic analysis of retrieved clots from 37 patients with acute MCA occlusion was performed. Patients underwent gradient-echo imaging before endovascular therapy. Retrieved clots underwent semiquantitative proportion analysis to quantify red blood cells, fibrin, platelets, and white blood cells by area. Correlations between clot compositions and stroke subtypes and susceptibility vessel signs on gradient-echo imaging were assessed.

RESULTS

Stroke etiology was classified as cardioembolism in 22 patients (59.4%), large-artery atherosclerosis in 8 (21.6%), and undetermined in 7 (18.9%). The clots from cardioembolism had a significantly higher proportion of red blood cells (37.8% versus 16.9%, P = .031) and a lower proportion of fibrin (32.3% versus 48.5%, P = .044) compared with those from large-artery atherosclerosis. The proportion of red blood cells was significantly higher in clots with a susceptibility vessel sign than in those without it (48.0% versus 1.9%, P < .001), whereas the proportions of fibrin (26.4% versus 57.0%, P < .001) and platelets (22.6% versus 36.9%, P = .011) were significantly higher in clots without a susceptibility vessel sign than those with it.

CONCLUSIONS

The histologic composition of clots retrieved from cerebral arteries in patients with acute stroke differs between those with cardioembolism and large-artery atherosclerosis. In addition, a susceptibility vessel sign on gradient-echo imaging is strongly associated with a high proportion of red blood cells and a low proportion of fibrin and platelets in retrieved clots.

Mobilization of CD8+ T Cells via CXCR4 Blockade Facilitates PD-1 Checkpoint Therapy in Human Pancreatic Cancer

PURPOSE

Pancreatic ductal adenocarcinoma (PDA) is rarely cured, and single-agent immune checkpoint inhibition has not demonstrated clinical benefit despite the presence of large numbers of CD8+ T cells. We hypothesized that tumor-infiltrating CD8+ T cells harbor latent antitumor activity that can be reactivated using combination immunotherapy.

EXPERIMENTAL DESIGN

Preserved human PDA specimens were analyzed using multiplex IHC (mIHC) and T-cell receptor (TCR) sequencing. Fresh tumor was treated in organotypic slice culture to test the effects of combination PD-1 and CXCR4 blockade. Slices were analyzed using IHC, flow cytometry, and live fluorescent microscopy to assess tumor kill, in addition to T-cell expansion and mobilization.

RESULTS

mIHC demonstrated fewer CD8+ T cells in juxtatumoral stroma containing carcinoma cells than in stroma devoid of them. Using TCR sequencing, we found clonal expansion in each tumor; high-frequency clones had multiple DNA rearrangements coding for the same amino acid binding sequence, which suggests response to common tumor antigens. Treatment of fresh human PDA slices with combination PD-1 and CXCR4 blockade led to increased tumor cell death concomitant with lymphocyte expansion. Live microscopy after combination therapy demonstrated CD8+ T-cell migration into the juxtatumoral compartment and rapid increase in tumor cell apoptosis.

CONCLUSIONS

Endogenous tumor-reactive T cells are present within the human PDA tumor microenvironment and can be reactivated by combined blockade of PD-1 and CXCR4. This provides a new basis for the rational selection of combination immunotherapy for PDA.See related commentary by Medina and Miller, p. 3747.

RETRACTED: CD44 expression denotes a subpopulation of gastric cancer cells in which Hedgehog signaling promotes chemotherapy resistance

PURPOSE

Gastric cancers may harbor a subset of cells with cancer stem cell (CSC) properties, including chemotherapy resistance, and CD44 is a gastric CSC marker. The Hedgehog (HH) pathway is a key developmental pathway that can be subverted by CSCs during tumorigenesis. Here, we examine the role of HH signaling in CD44(+) gastric cancer cells.

EXPERIMENTAL DESIGN

Gastric cancer cell lines, tumor xenografts, and patient tumors were examined.

RESULTS

Gastric cancer cell lines AGS, MKN-45, and NCI-N87 grown as spheroids or sorted for CD44(+) were found to have upregulation of HH pathway proteins. HH inhibition using Smoothened (Smo) shRNA or vismodegib (VIS) decreased spheroid formation and colony formation. CD44(+) cells, compared with unselected cells, were also resistant to 5-fluorouracil and cisplatin chemotherapy, and this resistance was reversed in vitro and in xenografts with Smo shRNA or VIS. CD44(+) cells also had significantly more migration, invasion, and anchorage-independent growth, and these properties could all be blocked with HH inhibition. Clinical tumor samples from a phase II trial of chemotherapy with or without VIS for advanced gastric cancer were analyzed for CD44 expression. In the chemotherapy alone group, high CD44 expression was associated with decreased survival, whereas in the chemotherapy plus VIS group, high CD44 expression was associated with improved survival.

CONCLUSIONS

HH signaling maintains CSC phenotypes and malignant transformation phenotypes in CD44(+) gastric cancer cells, and HH inhibition can reverse chemotherapy resistance in CD44(+) cells. Gastric cancer is a heterogeneous disease, and the strategy of combining chemotherapy with HH inhibition may only be effective in tumors with high CD44 levels.

Steroid receptor coactivator-1 coactivates activating protein-1-mediated transactivations through interaction with the c-Jun and c-Fos subunits

Steroid receptor coactivator-1 (SRC-1) specifically bound to the transcription factor AP-1 subunits c-Jun and c-Fos, as demonstrated by the yeast two-hybrid tests and glutathione S-transferase pull down assays. The c-Jun and c-Fos binding sites were localized to the C-terminal subregion of SRC-1 (amino acids 1101-1441) that encompasses the previously described histone acetyltransferase and receptor-binding domains. In mammalian cells, SRC-1, similar to the previous results with CBP-p300 (Arias, J., Alberts, A. S., Brindle, P., Claret, F. X., Smeal, T., Karin, M., Feramisco, J., and Montminy, M. (1994) Nature 370, 226-229; Bannister, A. J., and Kouzarides, T. (1995) EMBO J. 14, 4758-4762), potentiated the AP-1-mediated transactivations in a dose-dependent manner and derepressed the mutual inhibitions between nuclear receptors and AP-1. Furthermore, coexpression of p300 further enhanced this SRC-1-potentiated level of transactivations. Thus, we concluded that at least two distinct coactivator molecules may cooperate to regulate AP-1-dependent transactivations and mediate transrepression between AP-1 and nuclear receptors in vivo.

Nonspecific interstitial pneumonia with fibrosis: high-resolution CT and pathologic findings

OBJECTIVE

The purpose of our study was to describe high-resolution CT findings of nonspecific interstitial pneumonia with fibrosis and to compare findings seen on CT with pathologic findings.

MATERIALS AND METHODS

High-resolution CT findings of biopsy-proven non-specific interstitial pneumonia with fibrosis from 23 consecutive patients (one man and 22 women) were analyzed retrospectively by two chest radiologists. CT findings were compared with pathologic findings.

RESULTS

The predominant high-resolution CT finding, seen in all patients, was bilateral patchy areas of ground-glass opacity with (35%) or without (65%) areas of consolidation. Irregular linear opacities (87%), thickening of bronchovascular bundles (65%), and bronchial dilatation (52%) were also frequently seen. Honeycombing was not seen in any patient. All parenchymal abnormalities showed subpleural predominance. Areas of ground-glass opacity with or without irregular linear opacity or bronchial dilatation on CT corresponded pathologically to areas of interstitial thickening caused by varying degrees of interstitial inflammation and fibrosis showing temporal uniformity. Areas of consolidation, seen at five biopsy sites, represented the areas of bronchiolitis obliterans organizing pneumonia, foamy cell collections in alveolar spaces, or microscopic honeycombing with mucin stasis.

CONCLUSION

On high-resolution CT, nonspecific interstitial pneumonia with fibrosis is most commonly revealed as patchy subpleural areas of ground-glass opacity mixed with irregular linear opacity or bronchial dilatation. These areas represent interstitial thickening caused by varying degrees of interstitial inflammation, fibrosis, or both.

Anti-allergic and anti-inflammatory triterpenes from the herb of Prunella vulgaris

The activity-guided fractionation of the extract of the herb of Prunella vulgaris (Labiatae) led to the isolation of four triterpenes, i.e., betulinic acid, ursolic acid, 2 alpha,3 alpha-dihydroxyurs-12-en-28-oic acid, and 2 alpha-hydroxyursolic acid. One of these compounds, 2 alpha,3 alpha-dihydroxyursolic acid, demonstrated significant inhibition on the release of beta-hexosaminidase from the cultured RBL-2H3 cells in a dose-dependent manner; the IC50 value was calculated to be 57 microM. When the isolated compounds were tested for their effects on the production of nitric oxide from cultured murine macrophages, RAW 264.7 cells, ursolic acid and 2 alpha-hydroxyursolic acid exhibited strong inhibitory activities (IC50 values, 17 and 27 microM, respectively).

Stroke in pediatric acquired immunodeficiency syndrome

In a 4 1/2-year period, 4 of 68 children in a longitudinal study of neurological complications of human immunodeficiency virus (HIV) infection had clinical and/or neuroradiological evidence of stroke, yielding a clinical incidence of stroke in this population of 1.3% per year. During this period, 32 subjects died, and permission for autopsy was granted in 18 of the patients, including 3 of 4 who had clinical evidence of stroke. The prevalence of cerebrovascular pathological features in our consecutive autopsy series was higher than the clinical incidence. At autopsy cerebrovascular disease was documented in 6 (24%) of 25 children with HIV infection, including all 3 children who had clinical evidence of stroke. Four patients had intracerebral hemorrhages, 6 patients had nonhemorrhagic infarcts, and 3 had both. Hemorrhage was catastrophic in 1 child and clinically silent in 3 children, all of whom had immune thrombocytopenia. One child had an arteriopathy that affected meningocerebral arteries. In another child, the arteries of the circle of Willis were aneurysmally dilated. Two children had coexisting cardiomyopathy and subacute necrotizing encephalomyelopathy with vascular proliferation. These results suggest that stroke should be considered when children with HIV infection develop focal neurological signs.

Age-Specific Incidence of Melanoma in the United States

Importance

Melanoma is epidemiologically linked to UV exposure, particularly childhood sunburn. Public health campaigns are increasing sun-protective behavior in the United States, but the effect on melanoma incidence is unknown.

Objective

To examine the incidence of melanoma in the United States and whether any age-specific differences are present.

Design, Setting, and Participants

Observational, population-based registry data were extracted on July 3, 2018, from the combined National Program of Cancer Registries-Surveillance Epidemiology and End Results United States Cancer Statistics database for 2001-2015. Deidentified data for 988 103 cases of invasive melanoma, with International Classification of Diseases for Oncology histologic categorization codes 8720 to 8790, were used for analysis. Data analysis was performed from July 1, 2018, to March 1, 2019.

Main Outcomes and Measures

The annual rates of melanoma in pediatric, adolescent, young adult, and adult age groups were determined. Analyses were stratified by sex, and incidence rates were age-adjusted to the 2000 US standard population. Annual percentage change (APC) in incidence rate was calculated over the most recent decade for which data were available (2006-2015) using the weighted least squares method.

Results

In 2015, 83 362 cases of invasive melanoma were reported in the United States, including 67 in children younger than 10 years, 251 in adolescents (10-19 years), and 1973 in young adults (20-29 years). Between 2006 and 2015, the overall incidence rate increased from 200.1 to 229.1 cases per million person-years. In adults aged 40 years or older, melanoma rates increased by an APC of 1.8% in both men (95% CI, 1.4%-2.1%) and women (95% CI, 1.4%-2.2%). In contrast, clinically and statistically significant decreases were seen in melanoma incidence for adolescents and young adults. Specifically, incidence rates decreased by an APC of -4.4% for male adolescents (95% CI, -1.7% to -7.0%), -5.4% for female adolescents (95% CI, -3.3% to -7.4%), -3.7% for male young adults (95% CI, -2.5% to -4.8%), and -3.6% for female young adults (95% CI, -2.8% to -4.5%). Data on skin pigmentation and sun protection history were unavailable; similar trends were observed with data limited to non-Hispanic whites. Young adult women appeared to have twice the risk of melanoma as young adult men.

Conclusions and Relevance

The incidence of invasive melanoma in the United States appeared to decrease in adolescents and young adults from 2006 to 2015, and this finding contrasted with increases in older populations. These incidence trends suggest that public health efforts may be favorably influencing melanoma incidence in the United States.

Correlates of survival and the Daumas-Duport grading system for astrocytomas

In order to examine the correlation between prognosis and the histological features of nuclear atypia, mitosis, endothelial proliferation, and necrosis in supratentorial adult astrocytomas, the authors reviewed 251 such cases treated at the Massachusetts General Hospital between 1972 and 1980. One point was given for the presence of each feature. The total number of features was translated into a grade as follows: none of the four features = Grade 1 (one patient), one feature = Grade 2 (36 patients), two features = Grade 3 (33 patients), and three or four features = Grade 4 (181 patients). The period of survival was significantly associated with grade, the presence or absence of each of the four histological features, patient's age, type of operation, radiation therapy, and extent of tumor (log rank, p less than 0.05). The variables associated with grade were age (p less than 0.001) and radiation therapy (p less than 0.02). After adjustment for these variables using a Cox proportional-hazards model, the difference in overall survival time between patients in Grades 2 and 3 was not statistically significant. When comparable groups of patients were examined in terms of age or receipt of radiation therapy, the median survival times differed markedly. Patients 50 years of age or less had a median survival time of 68 months (Grade 2 tumors), 29 months (Grade 3 tumors), and 13 months (Grade 4 tumors). Patients over 50 years of age had a median survival time of 6 months (Grade 2 and 4 tumors) and 9 months (Grade 3 tumors). Those patients who had received radiation therapy had a median survival time of 68 months (Grade 2 tumors), 21 months (Grade 3 tumors), and 11 months (Grade 4 tumors). Those patients who did not receive radiation therapy had a median survival time of 1 month (Grade 2 tumors) and 2 months (Grade 3 and 4 tumors); over half of these patients died within 2 months of surgery. This grading system, originally proposed by Daumas-Duport, et al., is simple, objective, and reproducible, and correlates well with survival times. The authors recommend that astrocytomas be graded on a scale of 1 to 4, with Grade 1 reserved for the rare adult supratentorial astrocytoma with none of the four histological features.

Osteoporosis after cardiac transplantation

PURPOSE

The purpose of this study was to determine the prevalence of osteopenia and fractures and to describe the biochemical indices of mineral metabolism in patients who have undergone cardiac transplantation.

PATIENTS AND METHODS

Forty adult patients who had received a cardiac transplant between 1982 and 1990 and who were receiving immunosuppressive therapy with prednisone and cyclosporine A were studied. Bone densitometric measurements by dual-energy x-ray absorptiometry of the lumbar spine and femoral neck and radiographs of the thoracic and lumbar spine were obtained for all patients. Routine serum and urine biochemical values as well as more specialized biochemical analyses (intact parathyroid hormone, metabolites of vitamin D, and osteocalcin) were obtained.

RESULTS

Osteopenia was present in 28% of the patients at the lumbar spine and 20% of the patients at the femoral neck. Vertebral fractures were present in 35% of patients. In contrast to other patients receiving glucocorticoids, serum osteocalcin, a marker of bone formation, was elevated in 60% of patients.

CONCLUSIONS

Osteopenia and vertebral fractures are common in patients after cardiac transplantation. The presence of elevated osteocalcin levels suggests that the pathogenesis of the osteoporosis in these patients differs from that of glucocorticoid-induced osteoporosis.

KIT oncogene inhibition drives intratumoral macrophage M2 polarization

Imatinib reduces tumor cell KIT signaling and causes tumor cell apoptosis, which drives TAMs to shift from M1- to M2-like in mouse and human GIST.

Tumor-associated macrophages (TAMs) are a major component of the cancer microenvironment. Modulation of TAMs is under intense investigation because they are thought to be nearly always of the M2 subtype, which supports tumor growth. Gastrointestinal stromal tumor (GIST) is the most common human sarcoma and typically results from an activating mutation in the KIT oncogene. Using a spontaneous mouse model of GIST and 57 freshly procured human GISTs, we discovered that TAMs displayed an M1-like phenotype and function at baseline. In both mice and humans, the KIT oncoprotein inhibitor imatinib polarized TAMs to become M2-like, a process which involved TAM interaction with apoptotic tumor cells leading to the induction of CCAAT/enhancer binding protein (C/EBP) transcription factors. In human GISTs that eventually developed resistance to imatinib, TAMs reverted to an M1-like phenotype and had a similar gene expression profile as TAMs from untreated human GISTs. Therefore, TAM polarization depends on tumor cell oncogene activity and has important implications for immunotherapeutic strategies in human cancers.

Identification of a human cDNA clone for lysosomal type Ca2+-independent phospholipase A2 and properties of the expressed protein

A Ca2+-independent phospholipase A2 (PLA2) maximally active at pH 4 and specifically inhibited by the transition-state analogue 1-hexadecyl-3-trifluoroethylglycero-sn-2-phosphomethanol (MJ33) was isolated from rat lungs. The sequence for three internal peptides (35 amino acids) was used to identify a 1653-base pair cDNA clone (HA0683) from a human myeloblast cell line. The deduced protein sequence of 224 amino acids contained a putative motif (GXSXG) for the catalytic site of a serine hydrolase, but showed no significant homology to known phospholipases. Translation of mRNA produced from this clone in both a wheat germ system and Xenopus oocytes showed expression of PLA2 activity with properties similar to the rat lung enzyme. Apparent kinetic constants for PLA2 with dipalmitoylphosphatidylcholine as substrate were Km = 0.25 mM and Vmax = 1.89 nmol/h. Activity with alkyl ether phosphatidylcholine as substrate was decreased significantly compared with diacylphosphatidylcholine. Significant lysophospholipase, phospholipase A1, or 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine acetylhydrolase activity was not observed. Enzyme activity was insensitive to p-bromophenacyl bromide, bromoenol lactone, trifluoromethylarachidonoyl ketone, mercaptoethanol, and ATP, but was inhibited by MJ33 and diethyl p-nitrophenyl phosphate, a serine protease inhibitor. SDS-polyacrylamide gel electrophoresis with autoradiography of the translated [35S]methionine-labeled protein confirmed a molecular mass of 25.8 kDa, in good agreement with the enzyme isolated from rat lung. By Northern blot analysis, mRNA corresponding to this clone was present in both rat lung and isolated rat granular pneumocytes. These results represent the first molecular cloning of a cDNA for the lysosomal type Ca2+-independent phospholipase A2 group of enzymes.

PD-1/PD-L1 Blockade Enhances T-cell Activity and Antitumor Efficacy of Imatinib in Gastrointestinal Stromal Tumors

PURPOSE

Tyrosine kinase inhibitors are effective in gastrointestinal stromal tumors (GISTs) but often are of transient benefit as resistance commonly develops. Immunotherapy, particularly blockade of the inhibitory receptor programmed death 1 (PD-1) or the ligand programmed death ligand 1 (PD-L1), has shown effectiveness in a variety of cancers. The functional effects of PD-1/PD-L1 blockade are unknown in GISTs.

EXPERIMENTAL DESIGN

We analyzed tumor and matched blood samples from 85 patients with GISTs and determined the expression of immune checkpoint molecules using flow cytometry. We investigated the combination of imatinib with PD-1/PD-L1 blockade in Kit^V558Δ/+ mice that develop GISTs.

RESULTS

The inhibitory receptors PD-1, lymphocyte activation gene 3, and T-cell immunoglobulin mucin-3 were upregulated on tumor-infiltrating T cells compared with T cells from matched blood. PD-1 expression on T cells was highest in imatinib-treated human GISTs. Meanwhile, intratumoral PD-L1 expression was variable. In human GIST cell lines, treatment with imatinib abrogated the IFNγ-induced upregulation of PD-L1 via STAT1 inhibition. In Kit^V558Δ/+ mice, imatinib downregulated IFNγ-related genes and reduced PD-L1 expression on tumor cells. PD-1 and PD-L1 blockade in vivo each had no efficacy alone but enhanced the antitumor effects of imatinib by increasing T-cell effector function in the presence of KIT and IDO inhibition.

CONCLUSIONS

PD-1/PD-L1 blockade is a promising strategy to improve the effects of targeted therapy in GISTs. Collectively, our results provide the rationale to combine these agents in human GISTs. Clin Cancer Res; 23(2); 454-65. ©2016 AACR.

Spectral indices of cardiac autonomic function in obstructive sleep apnea

Spectral analysis of heart rate variability (HRV) is useful as a noninvasive means of assessing autonomic function in patients with obstructive sleep apnea (OSA). However, standard spectral measures, such as the ratio of low-frequency to high-frequency power (LHR) and normalized high-frequency power (NHFP), can be confounded by the abnormal breathing patterns that occur during sleep. To circumvent this limitation, we employed an autoregressive modeling approach to partition the RR time-series into a component that is correlated with respiration and a respiration-independent component. From these components, we derived two new spectral indices: the modified LHR (MLHR) and the average gain relating respiration to RR changes (GRSA). Six normals and seven OSA patients were studied in relaxed wakefulness and stage 2 sleep; during sleep, the OSA patients were studied without and with continuous positive airway pressure (CPAP) therapy. All four spectral indices showed significant differences between OSA patients and normals in both wakefulness and sleep, although the changes in MLHR and GRSA were substantially larger and less variable: MLHR (p < 0.0003) and GRSA (p < 0.0001) vs. LHR (p < 0.005) and NHFP (p < 0.004). However, in the OSA subjects, LHR and NHFP were unchanged by CPAP. By contrast, CPAP produced a highly significant increase in GRSA (p < 0.0004), as well as a decrease in MLHR (p < 0.03). Thus, by compensating for the effects of breathing pattern differences, MLHR and GRSA unmasked the effects of CPAP therapy, which has been shown in previous studies to reduce sympathetic activity and increase vagal cardiac modulation.

Inhibition of interleukin-12 and interferon-gamma production in immune cells by tanshinones from Salvia miltiorrhiza

Pharmacological control of interleukin-12 (IL-12) and interferon-gamma (IFN-gamma) production may be a key therapeutic strategy for modulating immunological diseases dominated by Th1-derived cytokine responses. In this study, we investigated the effects of three different tanshinone pigments from Salvia miltiorrhiza (tanshinone I, dihydrotanshinone, and cryptotanshinone) on IL-12 production in mouse macrophages and on IFN-gamma production in lymph node cells. All tested tanshinones significantly inhibited IL-12 production in lipopolysaccharide (LPS)-activated macrophages and also IFN-gamma production in keyhole limpet hemocyanin (KLH)-primed lymph node cells in a dose-dependent manner. Dihydrotanshinone was more effective than tanshinone I or cryptotanshinone. Tanshinones significantly inhibited the expression of IL-12 p40 gene at the mRNA level. Furthermore, tanshinones potently inhibited the promoter activation of IL-12 p40 gene and nuclear factor (NF)-kappaB binding to the kappaB site, suggesting that tanshinones may negatively regulate IL-12 production at the transcription level. These results may explain some known biological activities of tanshinones including their anti-inflammatory effect, and suggest a possible use of tanshinones in the treatment of immunological diseases dominated by Th1-derived cytokine responses.

Four years' experiences in the treatment of pituitary adenomas with gamma knife radiosurgery

To determine the tumor control rates and endocrinological responses after stereotactic radiosurgery for pituitary adenomas, we reviewed our experience in 65 patients (40 men, 25 women) treated in the Gamma Knife during the last 4 years. The mean age was 41.6 years (range 19-69 years). 43 patients had endocrinologically active tumors (20 growth hormone-secreting, 19 prolactin-secreting and 4 ACTH-secreting adenomas). 22 had nonfunctioning adenomas. 39 patients had a macroadenoma and 26 patients had a microadenoma. 33 patients underwent Gamma Knife radiosurgery for recurrent or residual tumors after microsurgery. 50 patients have had follow-up neuroimaging studies and/or hormonal evaluation. The follow-up period was 25.5 months (range 3 to 54 months). The margin of the tumor was incorporated within the 50 to 90% isodose. The mean number of isocenters was 3.8 and the mean marginal dose was 25.4 Gy (range 15 to 36 Gy). 27 out of 40 patients (65.7%) showed decreased tumor volume to less than 50% of the initial volume. In 17 out of 38 patients (44.7%) with endocrinologically active tumors, the hormonal level fell to within the normal range. Two patients had delayed complications: in one case there was pituitary insufficiency and in the other a visual disturbance. Gamma Knife radiosurgery seems to be effective adjuvant therapy for pituitary adenoma in selected cases. More long-term follow-up is required to evaluate the efficacy and side effects further.

Synthesis, topoisomerase I inhibition and antitumor cytotoxicity of 2,2':6',2"-, 2,2':6',3"- and 2,2':6',4"-terpyridine derivatives

For the development of new anticancer agents, 2,2':6',2"-, 2,2':6',3"- and 2,2':6',4"-terpyridine derivatives were designed and evaluated for their topoisomerase I inhibitory activity and antitumor cytotoxicity. Structure-activity relationship studies indicated that 2,2':6',2"-terpyridine derivatives were highly cytotoxic toward several human tumor cell lines, whereas 2,2':6',3"- and 2,2':6',4"-terpyridine derivatives were potent topoisomerase I inhibitors.

Curcumin inhibits Th1 cytokine profile in CD4+ T cells by suppressing interleukin-12 production in macrophages

1 Interleukin-12 (IL-12) plays a central role in the immune system by driving the immune response towards T helper 1 (Th1) type responses which are characterized by high IFN-gamma and low IL-4 production. In this study we investigated the effects of curcumin, a natural product of plants obtained from Curcuma longa (turmeric), on IL-12 production by mouse splenic macrophages and the subsequent ability of these cells to regulate cytokine production by CD4+ T cells. 2 Pretreatment with curcumin significantly inhibited IL-12 production by macrophages stimulated with either lipopolysaccharide (LPS) or head-killed Listeria monocytogenes (HKL). 3 Curcumin-pretreated macrophages reduced their ability to induce IFN-gamma and increased the ability to induce IL-4 in Ag-primed CD4+ T cells. Addition of recombinant IL-12 to cultures of curcumin-pretreated macrophages and CD4+ T cells restored IFN-gamma production in CD4+ T cells. 4 The in vivo administration of curcumin resulted in the inhibition of IL-12 production by macrophages stimulated in vitro with either LPS or HKL, leading to the inhibition of Th1 cytokine profile (decreased IFN-gamma and increased IL-4 production) in CD4+ T cells. 5 These findings suggest that curcumin may inhibit Th1 cytokine profile in CD4+ T cells by suppressing IL-12 production in macrophages, and points to a possible therapeutic use of curcumin in the Th1-mediated immune diseases.

Inhibition of porcine reproductive and respiratory syndrome virus by interferon-gamma and recovery of virus replication with 2-aminopurine

Porcine reproductive and respiratory syndrome virus (PRRSV) belongs to a group of RNA viruses that establish persistent infections. A proposed strategy for evading immunity during persistent PRRSV infection is by preventing the induction of IFN activity in pigs and/or by blocking the activation of antiviral proteins in permissive cells. IFN-gamma mRNA expression was observed in the lymph nodes and lungs of pigs infected with wild-type PRRSV strain SDSU-23983. Pretreatment of MARC-145 cells with IFN-gamma inhibited wild-type (SDSU-23983 P6) and culture-adapted (SDSU-23983 P136) PRRS viruses in a dose-dependent manner and at relatively low concentrations. The effect of IFN-gamma on virus replication included reductions in the number of infected cells, virus yield, and RNA content in single cells. Virus replication was partially restored by the addition of 2-aminopurine (2-AP), an inhibitor of dsRNA inducible protein kinase (PKR). The addition of 2-AP also restored the viral RNA content per cell to near normal levels, suggesting that inhibition of viral RNA synthesis was through PKR. The principal difference between P6 and P136 isolates was the recovery of P136 replication with lower concentrations of 2-AP. Immunostaining with anti-PKR antibody showed a redistribution of PKR from the cytoplasm into nucleoli of infected cells.

Neoantigen-specific CD4+ T cells in human melanoma have diverse differentiation states and correlate with CD8+ T cell, macrophage, and B cell function

CD4⁺ T cells that recognize tumor antigens are required for immune checkpoint inhibitor efficacy in murine models, but their contributions in human cancer are unclear. We used single-cell RNA sequencing and T cell receptor sequences to identify signatures and functional correlates of tumor-specific CD4⁺ T cells infiltrating human melanoma. Conventional CD4⁺ T cells that recognize tumor neoantigens express CXCL13 and are subdivided into clusters expressing memory and T follicular helper markers, and those expressing cytolytic markers, inhibitory receptors, and IFN-γ. The frequency of CXCL13⁺ CD4⁺ T cells in the tumor correlated with the transcriptional states of CD8⁺ T cells and macrophages, maturation of B cells, and patient survival. Similar correlations were observed in a breast cancer cohort. These results identify phenotypes and functional correlates of tumor-specific CD4⁺ T cells in melanoma and suggest the possibility of using such cells to modify the tumor microenvironment.

Blockade of interleukin 10 potentiates antitumour immune function in human colorectal cancer liver metastases

OBJECTIVE

Programmed cell death protein 1 (PD-1) checkpoint inhibition and adoptive cellular therapy have had limited success in patients with microsatellite stable colorectal cancer liver metastases (CRLM). We sought to evaluate the effect of interleukin 10 (IL-10) blockade on endogenous T cell and chimeric antigen receptor T (CAR-T) cell antitumour function in CRLM slice cultures.

DESIGN

We created organotypic slice cultures from human CRLM (n=38 patients' tumours) and tested the antitumour effects of a neutralising antibody against IL-10 (αIL-10) both alone as treatment and in combination with exogenously administered carcinoembryonic antigen (CEA)-specific CAR-T cells. We evaluated slice cultures with single and multiplex immunohistochemistry, in situ hybridisation, single-cell RNA sequencing, reverse-phase protein arrays and time-lapse fluorescent microscopy.

RESULTS

αIL-10 generated a 1.8-fold increase in T cell-mediated carcinoma cell death in human CRLM slice cultures. αIL-10 significantly increased proportions of CD8⁺ T cells without exhaustion transcription changes, and increased human leukocyte antigen - DR isotype (HLA-DR) expression of macrophages. The antitumour effects of αIL-10 were reversed by major histocompatibility complex class I or II (MHC-I or MHC-II) blockade, confirming the essential role of antigen presenting cells. Interrupting IL-10 signalling also rescued murine CAR-T cell proliferation and cytotoxicity from myeloid cell-mediated immunosuppression. In human CRLM slices, αIL-10 increased CEA-specific CAR-T cell activation and CAR-T cell-mediated cytotoxicity, with nearly 70% carcinoma cell apoptosis across multiple human tumours. Pretreatment with an IL-10 receptor blocking antibody also potentiated CAR-T function.

CONCLUSION

Neutralising the effects of IL-10 in human CRLM has therapeutic potential as a stand-alone treatment and to augment the function of adoptively transferred CAR-T cells.

Mucoepidermoid carcinoma of the tracheobronchial tree: radiographic and CT findings in 12 patients

PURPOSE

To determine the radiographic and computed tomographic (CT) findings and clinical features of mucoepidermoid carcinoma of the tracheobronchial tree.

MATERIALS AND METHODS

Chest radiographic and CT findings and clinical features of 12 histopathologically proved mucoepidermoid carcinomas in 12 consecutive patients (five male, seven female; age range, 9-72 years; mean age, 36 years) were reviewed retrospectively.

RESULTS

The tumors were located at the distal trachea (n = 1) or at a main (n = 2), lobar (n = 1), or segmental (n = 8) bronchus. On chest radiographs, the tumors appeared as central masses with post-obstructive pneumonia or peripheral atelectasis in four patients and as solitary pulmonary or endotracheobronchial nodules in eight. At CT, the tumors were all smoothly oval (n = 6) or lobulated (n = 6) in shape (ranging 9-40 mm in diameter), adapting to the branching features of the airways. Punctate calcification within the tumor was seen in six patients. Neither metastasis nor recurrence was seen after the surgical resection (follow-up of 8-103 months; mean, 30 months).

CONCLUSION

Mucoepidermoid carcinoma of the tracheobronchial tree, usually located in a segmental bronchus, appears at CT as a smoothly oval or lobulated airway mass. It adapts to the branching features of the airways.