Acquisition of an immunosuppressive protumorigenic macrophage phenotype depending on c-Jun phosphorylation

The inflamed tumor microenvironment plays a critical role in tumorigenesis. However, the mechanisms through which immune cells, particularly macrophages, promote tumorigenesis have only been partially elucidated, and the full scope of signaling pathways supplying macrophages with protumorigenic phenotypes still remain largely unknown. Here we report that germ-line absence of c-Jun N-terminal phosphorylation at serines 63 and 73 impedes inflammation-associated hepatocarcinogenesis, yet deleting c-Jun only in hepatocytes does not inhibit hepatocellular carcinoma (HCC) formation. Moreover, in human HCC-bearing livers, c-Jun phosphorylation is found in inflammatory cells, whereas it is mostly absent from malignant hepatocytes. Interestingly, macrophages in livers of mice with chronic hepatitis gradually switch their phenotype along the course of disease. Macrophage phenotype and density are dictated by c-Jun phosphorylation, in vitro and in vivo. Transition of macrophage phenotype, from antitumorigenic to protumorigenic, occurs before tumorigenesis, resulting in the production of various chemokines, including chemokine (C-C motif) ligand 17 (CCL17) and CCL22. Such signals, emanating from the liver microenvironment, direct the recruitment of regulatory T cells, which are known to facilitate HCC growth. Our findings identify c-Jun phosphorylation as a key mediator of macrophage education and point to the recruitment of immunosuppressive regulatory T cells as a possible protumorigenic mechanism.The network of interactions among cells that comprise tumors has a major influence on tumor progression. Tumor-associated macrophages (TAMs) are singled out as possibly the most significant ones, other than the malignant cells per se. Importantly, macrophages can assume both antitumorigenic (designated M1 macrophages) and protumorigenic (designated M2) phenotypes, yet the mechanisms that modulate this switch are largely unknown (1, 2). It is generally maintained that this switch is mediated by signals that emanate from the tumor cells, hence the term “tumor-educated macrophages.” Chronic inflammation plays a key pathogenetic role in hepatocellular carcinoma (HCC). However, chronic inflammation is a complex process, which may play both protumorigenic and antitumorigenic roles via the action of many cytokines and various effects of different protumorigenic and antitumorigenic innate and adaptive immune cells (3).Experimental proof for a protumorigenic role of microenvironment residents was shown for invasive and metastatic tumors. For example, Budhu et al. identified a specific immune signature that drives the metastatic spread of HCC (4), and Qian et al. showed that chemokine (C-C motif) ligand 2 (CCL2) facilitates breast cancer metastasis (5). Furthermore, we and others have shown that inflammatory-cell–induced signaling events in epithelial cells promote carcinogenesis (6, 7). Epithelial–stroma interactions may also be important in the very initial phases of tumor generation (8), and it is possible that immunosurveillance could resist tumorigenesis at these early stages (9). We hypothesized that, in specific pathological states, macrophage education may occur before tumorigenesis, perhaps even as a prerequisite for it. This hypothesis could form the foundation for new preventive treatments aimed at the reeducation of immune cells in individuals susceptible to developing cancer.Many reports support the existence of immunosurveillance against nonviral cancers (10). A distinction can now be made between protumorigenic inflammation, characterized by tumor infiltration by Th2 cells, Foxp3-positive regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and M2 macrophages, and antitumorigenic inflammation, characterized by infiltration with Th1 cells, CD8⁺ cytotoxic T lymphocytes, and M1 macrophages (11). Previous studies have identified several factors that are secreted by TAMs and promote tumor progression, including EGF, VEGF, MMP7/9, and CCL18 (12–15), which are thought to affect tumor cell phenotype and tumor vasculature.Patients with active chronic hepatitis are a unique example of a patient group carrying an extremely high risk for developing HCC, one of the deadliest human tumors (16, 17). Multiple signaling pathways are known to regulate diverse aspects of immune cell phenotype and function; among these pathways, the c-Jun NH₂ kinase (JNK)/c-Jun signaling pathway is known to be involved in both inflammatory and cancer processes (18). JNK kinases are responsible for phosphorylating c-Jun at Ser-63 and -73, which are essential for stimulation of c-Jun activity. However, JNK functions in cancer have been difficult to predict because JNK is involved both in cell proliferation and cell survival as well as in cell death (19). The role of JNK kinases in HCC is controversial, with different models showing protumorigenic and antitumorigenic roles for JNK (20). We therefore set out to study the role of c-Jun N-terminal phosphorylation (JNP) in inflammation-associated HCC.     

Catheter Aspiration after Every Stage during Primary Percutaneous Angioplasty; ADMIT Trial

We assess the epicardial and microcirculation flow characteristics, and clinical outcome by using catheter aspiration after each stage of primary percutaneous coronary intervention (PPCI). Conflicting data are reported regarding early and late benefit of using aspiration catheter in the initial phase PPCI. A total of 100 patients with ST-segment elevation acute myocardial infarction (STEMI) were included: 51 underwent PPCI without using an aspiration device (SA group) and 49 underwent PPCI by activating an aspiration catheter after each stage of procedure; wiring, ballooning and stenting, respectively (MA group). Thrombolysis in myocardial infarction (TIMI) flow grade, TIMI frame counts and myocardial blush grade (MBG) were evaluated in each group during every stage of procedure. Major adverse cardiac events were evaluated in the index hospitalization and during 30 and 180 days of follow-up.A TIMI flow grade 2–3 was more prevalent in the MA group compared with the SA group only after wiring: 65.9 versus 39.1% (p = 0.01), but TIMI frame counts were lower in the MA versus SA group throughout all procedural steps. MBG 2–3 was statistically higher in the MA group compared with the SA group mainly after wiring. After stenting there were no significant changes in both epicardial and microcirculation flow parameters. There were no significant differences between the groups in early and late clinical outcomes. Improved flow parameters were noticed in the MA group only by activating the aspiration device after wiring. This early advantage disappeared after stenting. The initial better flow characteristic in the MA group was not translated into a better early or late clinical outcome.     

The prevalence and risk factors for atrioesophageal fistula after percutaneous radiofrequency catheter ablation for atrial fibrillation: the Canadian experience

Purpose

Atrioesophageal fistula (AEF) is an infrequent complication of radiofrequency (RF) ablation for atrial fibrillation (AF). The aim of this study was to determine the prevalence and operator-dependent factors associated with AEF using a nationwide survey of electrophysiologists (EP).

Methods

Thirty-eight EPs performing AF ablation between 2008 and 2012 were invited to complete a web-based questionnaire assessing the prevalence and factors associated with AEF.

Results

Responses were obtained from 25 EPs (68 %) accounting for 7,016 AF ablations. Five cases of proven AEF (0.07 %) were reported. Operators who reported AEF [AEF (+)] more often used general anesthesia (GA) [90 % AEF (+) vs. 44 % AEF (?), p?=?0.046]. AEF (+) operators were also more likely to be users of the non-brushing technique in the posterior wall of the LA [5 (100 %) AEF (+) vs. 5 (25 %) AEF (?), p?=?0.005]. The combined usage of GA and non-brushing technique during LA posterior wall ablation had a strong association with AEF (+) operators [4 (80 %) AEF (+) vs. 2 (10 %) AEF (?), p?=?0.002]. There was a trend towards higher maximal RF energy setting in the posterior wall [47.4 + 7.6 AEF (+) vs. 40.2 + 8 AEF (?), p?=?0.09]. Other procedure parameters were similar.

Conclusions

The reported prevalence of AEF among Canadian AF ablators is 0.07 %. AEF was associated with high mortality. The use of GA and non-brushing movements during posterior wall ablation were two factors associated with AEF.     

Male prolactinomas presenting with normal testosterone levels

In men harboring prolactinoma the most common symptoms are related to hypogonadism, including decreased libido, erectile dysfunction, and gynecomastia. These men characteristically present with elevated serum prolactin (PRL) levels, suppressed gonadotropins, and low testosterone levels. We studied a group of 11 unique men with prolactinomas presenting with testosterone levels within the normal range (≥2.6 ng/ml; cohort A), and compared them to 11 prolactinoma men with borderline baseline testosterone (2.1–2.5 ng/ml; cohort B) and to a cohort of 34 prolactinoma patients with low testosterone levels (≤2 ng/ml; cohort C). Mean testosterone levels at presentation were 3.91 ± 0.9 ng/ml in cohort A (range, 2.6–5.2 ng/ml), 2.44 ± 0.16 ng/ml in cohort B and 0.96 ± 0.6 in cohort C (p < 0.001). Mean baseline PRL levels were >20 times above normal in cohort A compared to >100 times above normal in cohorts B and C. Symptoms of hypogonadism were present in 55, 64 and 76 % of men in groups A, B and C, respectively. There was a trend towards a larger tumor size in the low testosterone group (p = 0.06). Visual fields defects at presentation were more prevalent in this cohort (C). With cabergoline, testosterone level increased from 3.91 to 6.42 ng/ml (Δ = 2.51 ng/ml) in cohort A, from 2.44 to 5.63 ng/ml (Δ = 3.19 ng/ml) in cohort B, and from 0.96 to 3.30 ng/ml (Δ = 2.34 ng/ml) in cohort C (p < 0.05 for each group). Symptoms of hypogonadism improved following treatment in 83 % of symptomatic men in cohort A. Normal testosterone does not exclude the likelihood of prolactinoma in men. When treated with cabergoline, testosterone levels in these men can increase higher within the normal range together with clinical improvement.     

Elevated white blood cell counts in Cushing’s disease: association with hypercortisolism

Background

Glucocorticoid receptors are expressed in white blood cells (WBC’s) and are known to play a role in cell adhesion and WBC’s recruitment from bone marrow. In Cushing’s disease leukocytosis is frequently mentioned as laboratory finding. However, there is no data on the prevalence of this finding among patients, or correlation with disease severity.

Purpose

To investigate the prevalence of leukocytosis in patients with Cushing’s disease, alterations in other blood count parameters and correlation with degree of hypercortisolism.

Methods

Data of 26 patients diagnosed and followed for Cushing’s disease at our clinic was reviewed. Two patients had disease relapse after complete remission and were studied as 2 separate events.

Results

Of the 26 patients, 17 were women (71 %), with a mean age of 39.8 ± 12.7 years. Mean baseline WBC count was 10,500 ± 2,600 cells/μl and dropped to 8,400 ± 1,900 cells/μl (p < 0.05) after treatment, mean neutrophil count at baseline was 7,600 ± 2,600 cells/μl and dropped to 5,300 ± 1,700 cells/μl (p < 0.05), lymphocyte count was 2,000 ± 600 cells/μl and raised to 2,300 ± 600 cells/μl (p < 0.05), hemoglobin was 13.7 ± 1.2 g/dl and dropped to 12.8 ± 1.4 g/dl (p < 0.05), and platelet number did not change. Elevated WBC count was present in 11/28 cases (40 %). Those patients with normal baseline WBC (mean 9,000 ± 1,500 cells/μl) dropped also to 7,700 ± 1,300 cells/μl after treatment (p < 0. 05). There was a significant positive correlation between decrease in UFC secretion and change in WBC’s following treatment (r = 0.67, p < 0.01).

Conclusions

Patients with Cushing’s disease present with leukocytosis in approximately 40 % of cases. In most cases, including those without elevated baseline count, the WBC’s decreased with disease remission, demonstrating the effect of glucocorticoids on these blood cells.