Uzi Izhar

CD4+CXCR4highCD69+ T cells accumulate in lung adenocarcinoma.

The chemokine receptor CXCR4 is involved in the growth and metastasis of tumor cells. However, the expression of its ligand, the chemokine CXCL12, in tumors and its role in regulating the accumulation of immune cells within the tumors is not clear. Using ELISA and immunohistochemistry we found that CXCL12 is expressed in the majority of nonsmall cell lung cancer tissue sections obtained from stage IA to IIB nonsmall cell lung cancer patients undergoing operation. Histopathologic examination of these sections indicated that high CXCL12 expression correlated with increased tumor inflammation. In addition, disease recurrence rates in a subgroup of adenocarcinoma patients showed a tendency to correlate with high CXCL12 expression in the tumor. Isolation of adenocarcinoma-infiltrating immune cells demonstrated an increase in the percentage of CD4+CD69+CXCR4+ T cells as compared with normal lung tissue. About 30% of these cells expressed the regulatory T cell markers CD25high and FoxP3. The percentage of CD8 T cells within the tumor did not change, however; the percentage of NK and NK T cells was significantly reduced. In correlation with CXCR4 expression, CD4 T cells showed increased migration in response to CXCL12 compared with CD8 T cells and NK cells. Overall, these observations suggest that CXCL12 expression may influence tumor progression by shaping the immune cell population infiltrating lung adenocarcinoma tumors.

CXCR4/CXCL12 Axis in Non Small Cell Lung Cancer (NSCLC) Pathologic Roles and Therapeutic Potential

Lung cancer is the second most common malignancy and the leading cause of cancer-related death in the western world. Moreover, despite advances in surgery, chemotherapy and radiotherapy, the death rate from lung cancer remains high and the reported overall five-year survival rate is only 15%. Thus, novel treatments for this devastating disease are urgently needed. Chemokines, a family of 48 chemotactic cytokines interacts with their 7 transmembrane G-protein-coupled receptors, to guide immune cell trafficking in the body under both physiologic and pathologic conditions. Tumor cells, which express a relatively restricted repertoire of chemokine and chemokine receptors, utilize and manipulate the chemokine system in a manner that benefits both local tumor growth and distant dissemination. Among the 19 chemokine receptors, CXCR4 is the receptor most widely expressed by malignant tumors and whose role in tumor biology is most thoroughly studied. The chemokine CXCL12, which is the sole ligand of CXCR4, is highly expressed in primary lung cancer as well as in the bone marrow, liver, adrenal glands and brain, which are all sites for lung cancer metastasis. This review focuses on the pathologic role of the CXCR4/CXCL12 axis in NSCLC and on the potential therapeutic implication of targeting this axis for the treatment of NSCLC.

Interaction between neoplastic cells and cancer-associated fibroblasts through the CXCL12/CXCR4 axis: Role in non–small cell lung cancer tumor proliferation

OBJECTIVES Carcinoma-associated fibroblasts are reported to communicate microenvironment-derived signals through chemokine/chemokine receptor interaction, influencing carcinogenesis. We sought to characterize roles of CXCL12/CXCR4 in crosstalk between non-small cell lung cancer epithelial cell and carcinoma-associated fibroblasts and in tumor growth. METHODS Non-small cell lung cancer tumor samples obtained at surgery and from tumor arrays, as well as primary carcinoma-associated fibroblast and epithelial cell lines generated from fresh tumors, were assessed for CXCL12/CXCR4 expression, tissue localization, and production. Colony assays, extracellular signal-regulated kinase signaling, and chemokine production were measured to assess cancer cell responsiveness to CXCL12 stimulation with or without CXCR4 antagonists. RESULTS CXCL12 and CXCR4 were detected in all major subtypes of non-small cell lung cancer. CXCL12-expressing carcinoma-associated fibroblasts were mostly located near CXCL12-negative tumor cells, whereas CXCL12-positive tumor cells were mostly surrounded by CXCL12-negative stroma. Intratumoral CXCL12 levels were significantly higher than serum levels. CXCL12 expression correlated with advanced disease stage. In vitro, tumor cell lines produced variable amounts of CXCL12 and expressed high levels of CXCR4. Carcinoma-associated fibroblasts cell lines produced high amounts of CXCL12 and expressed variable levels of CXCR4. Stimulation of non-small cell lung cancer neoplastic cells with CXCL12 increased colony-forming capacity, induced extracellular signal-regulated kinase phosphorylation, and production of the proinflammatory chemokine CCL20. CXCR4 antagonists attenuated these effects. CONCLUSIONS Interaction between carcinoma-associated fibroblasts and tumor epithelial cells through the CXCL12/CXCR4 axis plays a role in non-small cell lung cancer tumor proliferation, marking this axis as a target for immune intervention.

Involvement of CCR6/CCL20/IL-17 Axis in NSCLC Disease Progression

Objectives Autocrine and paracrine chemokine/chemokine receptor-based interactions promote non-small-cell-lung-cancer (NSCLC) carcinogenesis. CCL20/CCR6 interactions are involved in prostatic and colonic malignancy pathogenesis. The expression and function of CCL20/CCR6 and its related Th-17 type immune response in NSCLC is not yet defined. We sought to characterize the role of the CCL20/CCR6/IL-17 axis in NSCLC tumor growth. Methods A specialized histopathologist blindly assessed CCL20/CCR6 expression levels in 49 tissue samples of NSCLC patients operated in our department. Results were correlated to disease progression. Colony assays, ERK signaling and chemokine production were measured to assess cancer cell responsiveness to CCL20 and IL-17 stimulation. Results CCL20 was highly expressed in the majority (38/49, 77.5%) of tumor samples. Only a minority of samples (8/49, 16.5%) showed high CCR6 expression. High CCR6 expression was associated with a shorter disease-free survival (P = 0.008) and conferred a disease stage-independent 4.87-fold increased risk for disease recurrence (P = 0.0076, CI 95% 1.52–15.563). Cancerous cell colony-forming capacity was increased by CCL20 stimulation; this effect was dependent in part on ERK phosphorylation and signaling. IL-17 expression was detected in NSCLC; IL-17 potentiated the production of CCL20 by cancerous cells. Conclusion Our findings suggest that the CCL20/CCR6 axis promotes NSCLC disease progression. CCR6 is identified as a potential new prognostic marker and the CCL20/CCR6/IL-17 axis as a potential new therapeutic target. Larger scale studies are required to consolidate these observations.

In vitro and in vivo therapeutic efficacy of CXCR4 antagonist BKT140 against human non–small cell lung cancer

OBJECTIVES CXCR4/CXCL12 interactions promote non-small cell lung cancer (NSCLC) growth and dissemination. Furthermore, this axis might promote NSCLC resistance to chemotherapy and/or radiotherapy. Therefore, the CXCR4/CXCL12 axis constitutes an attractive therapeutic target for the treatment of NSCLC. We aimed to characterize the therapeutic efficacy of the novel CXCR4 antagonist BKT140 against human NSCLC. METHODS We determined the CXCR4 expression in 5 NSCLC cell lines (H358, A549, H460, H1299, and L4). We then tested the colony-forming capacity and proliferation of these cells in the presence of CXCL12 and BKT140. Next, we measured the in vivo growth of A549 and H460 xenografts with or without BKT140 treatment. Finally, we examined, in vitro, the potential antiproliferative effect of BKT140 combined with cisplatin or paclitaxel and after irradiation of NSCLC cells. RESULTS All tested cell lines expressed CXCR4 and showed increased colony formation in response to CXCL12 stimulation. BKT140 reduced the colony-forming capacity of NSCLC cells. Proliferation assays demonstrated both cytotoxic and cytostatic properties for this peptide. H460 cells were the most sensitive to BKT140 and A549 cells the least. Subcutaneous administration of BKT140 significantly delayed the development of H460 xenografts and showed a similar trend for A549 xenografts. Finally, the antiproliferative effects of BKT140 appears to be additive to those of chemotherapeutic drugs and radiotherapy. CONCLUSIONS Targeting the CXCL12/CXCR4 axis with BKT140 attenuated NSCLC cells tumor growth and augmented the effects of chemotherapy and radiotherapy. Future research will benefit from delineating the downstream mechanism of BKT140 action and defining BKT140 susceptibility markers.

Paraganglioma of the mediastinum: challenges in diagnosis and surgical management

Mediastinal paraganglioms are rare, highly vascularized tumors arising from chromaffin tissue located in the para-aortic ganglia. Tumors tend to invade bordering structures and may also form metastasis. Up to 50% of patients are asymptomatic and diagnosis is incidental. Presenting symptoms are related to catecholamine hypersecretion or to a mass effect. Complete surgical resection remains the standard of care due to malignant potential of the tumor and poor response to chemotherapy or radiation. Strategic location of the tumor in proximity to great vessels, trachea, and recurrent laryngeal nerve poses challenge for the surgeon. We report a case of a 59-year old asymptomatic female who was incidentally diagnosed with a middle mediastinal mass on a positron-emission tomography (PET-CT) scan performed as part of breast cancer surveillance. Complete resection of the tumor was achieved using cardiopulmonary bypass. The patient recovered uneventfully and in a ten-month follow up there is no evidence of recurrence.

Positron emission tomography in interstitial lung disease.

Background and objectives:  A high rate of glycolysis may reflect the inflammatory activity of interstitial lung disease (ILD). This prospective study investigated whether PET can distinguish IPF, a primarily fibrotic process, from other entities of ILD that have a marked inflammatory component.

Invasive Scytalidium dimidiatum Infection in an Immunocompetent Adult

ABSTRACT Scytalidium dimidiatum, a dematiaceous fungus, has been well established as an agent of dermatomycosis. There are few reports of invasive infection caused by S. dimidiatum; most infections occurred in immunocompromised hosts. We present an immunocompetent patient with pleural S. dimidiatum infection and review nine other published cases of invasive S. dimidiatum infections.

Extracellular matrix constituents interfere with Newcastle disease virus spread in solid tissue and diminish its potential oncolytic activity

Advanced melanoma cells, characterized by resistance to chemotherapy, have been shown to be highly sensitive to oncolysis by Newcastle disease virus (NDV). In the present study, we investigated the capacity of NDV to specifically infect and spread into solid tissues of human melanoma and lung carcinoma, in vivo and ex vivo. For this purpose a new model of SCID-beige mice implanted with human melanoma was developed. Surprisingly, the replication competent NDV-MTH and the attenuated, single-cycle replication NDV-HUJ strains, demonstrated a similar oncolytic activity in the melanoma-implanted mice. Further, ex vivo analysis, using organ cultures derived from the melanoma tissues indicated a limited spread of the two NDV strains in the tissue. Extracellular matrix (ECM) molecules, notably heparin sulfate and collagen, were found to limit viral spread in the tissue. This observation was validated with yet another solid tumour of human lung carcinoma. Taken together, the results indicate that the ECM acts as a barrier to virus spread within solid tumour tissues and that this restriction must be overcome to achieve effective oncolysis with NDV.

Beneficial Effect of Aspirin on Renal Function Post-Cardiopulmonary Bypass

Urine thromboxane, plasma creatinine, and creatinine clearance were determined perioperatively in 20 patients undergoing coronary bypass surgery. Ten patients took aspirin until the day of surgery, and 10 discontinued aspirin at least one week before surgery. A significant increase in urine thromboxane following establishment of cardiopulmonary bypass was observed only in the control group. Plasma creatinine increased in the control group on the 1st postoperative day (from 81.9 ± 13.2 to 97.6 ± 13.2 μmol·L−1, p = 0.02) and decreased next day to the preoperative level (82.7 ± 9 μmol·L−1, p = 0.03). In the aspirin group, creatinine remained unchanged on the 1st postoperative day (89.4 ± 14.2 vs. 87.2 ± 7.7 μmol·L−1, p = 0.6), and increased significantly on the 2nd day (101.4 ± 8.5 μmol·L−1, p = 0.01). The aspirin group had higher creatinine levels (p < 0.0001) and lower creatinine clearance (60.2 ± 16.5 vs. 82 ± 25.7 mL·min−1, p < 0.0001) than the control group on the 2nd postoperative day. A significant positive correlation was seen between urine thromboxane and creatinine on day 2 in both groups (r = 0.6). Aspirin administrated before coronary surgery may have a beneficial effect on renal function, probably mediated by its antiplatelet activity and thromboxane inhibition.