Emerging Role of IL-4-Induced Gene 1 as a Prognostic Biomarker Affecting the Local T-Cell Response in Human Cutaneous Melanoma.

Several studies have emphasized the importance of immune composition of the melanoma microenvironment for clinical outcome. The contribution of IL4I1, a phenylalanine oxidase with immunoregulatory functions, has not been yet explored. Here we studied a primary cutaneous melanoma series from stage I-III patients to investigate the association between in situ IL4I1 expression and clinical parameters or tumor-infiltrating T-cell subsets. IL4I1 was detected in 87% of tumors and was mainly expressed by tumor-associated macrophages and very rare FoxP3+ regulatory T cells. The proportion of IL4I1+ cells was higher in patients with an ulcerated melanoma or with a positive sentinel lymph node and tended to correlate with a rapid relapse and shorter overall survival. This proportion also correlated positively with the presence of regulatory T cells and negatively with the presence of cytotoxic CD8+ T cells. The location of IL4I1+ cells may also be relevant to predict prognosis, because their presence near tumor cells was associated with sentinel lymph node invasion and higher melanoma stage. Collectively, our data show that IL4I1+ cells shape the T-cell compartment and are associated with a higher risk of poor outcome in melanoma, supporting a key role for IL4I1 in immune evasion.

Lipopolysaccharide (LPS) Promotes Apoptosis in Human Breast Epithelial × Breast Cancer Hybrids, but Not in Parental Cells.

Toll-like receptors (TLRs) belong to the group of pathogen recognition receptors known to play a crucial role in the innate immune system. In cancer, TLR expression is still debated controversially due to contradictory results reporting that both induction of apoptosis as well as tumor progression could depend on TLR signaling, whereby recent data rather indicate a pro-tumorigenic effect. The biological phenomenon of cell fusion has been associated with cancer progression due to findings revealing that fusion-derived hybrid cells could exhibit properties like an increased metastatogenic capacity and an increased drug resistance. Thus, M13MDA435 hybrid cell lines, which derived from spontaneous fusion events between human M13SV1-EGFP-Neo breast epithelial cells and human MDA-MB-435-Hyg breast cancer cells, were investigated. Cultivation of cells in the presence of the TLR4 ligand LPS potently induced apoptosis in all hybrid clones, but not in parental cells, which was most likely attributed to differential kinetics of the TLR4 signal transduction cascade. Activation of this pathway concomitant with NF-κB nuclear translocation and TNF-α expression was solely observed in hybrid cells. However, induction of LPS mediated apoptosis was not TNF-α dependent since TNF-α neutralization was not correlated to a decreased amount of dead cells. In addition to TNF-α, LPS also caused IFN-ß expression in hybrid clones 1 and 3. Interestingly, hybrid clones differ in the mode of LPS induced apoptosis. While neutralization of IFN-ß was sufficient to impair the LPS induced apoptosis in M13MDA435-1 and -3 hybrids, the amount of apoptotic M13MDA435-2 and -4 hybrid cells remained unchanged in the presence of neutralizing IFN-ß antibodies. In summary, the fusion of non-LPS susceptible parental human breast epithelial cells and human breast cancer cells gave rise to LPS susceptible hybrid cells, which is in view with the cell fusion hypothesis that hybrid cells could exhibit novel properties.

Fusion in cancer: an explanatory model for aneuploidy, metastasis formation, and drug resistance.

Aneuploidy, metastasis formation, and drug resistance are major issues to overcome in most cancers. If there exists common underlying proceedings for the formation of these phenomena is still unknown. The searching and thereby better understanding of causal mechanisms could promote the generation of drugs targeting the ultimate cause of these cancer promoting events. The merging of a cancer cell with another cancer cell or normal cell could be one explanation how cancer cells could gain advantageous properties and escape eliminating cell fates thereby foster cancer progression. This chapter summarizes how cell-cell fusion could directly be involved in the pathogenesis of cancer and which often cancer associated mechanisms, like viral infections or chronic inflammation, are hitherto proposed to trigger cell fusion in cancer context.

Personalized Cancer Medicine 2011: Toward Individualized Cancer Treatments. XV International Fritz Bender Symposium Held on February 21 to 23, 2011 at Matrix, Biopolis, Singapore.

At the symposium, approaches to individualized cancer medicine were considered, from basic sciences (genetics, epigenetics, biological tumor signatures) to clinical investigations, including strategies about how best to undertake the clinical development of targeted agents.

Neutrophil granulocytes promote the migratory activity of MDA-MB-468 human breast carcinoma cells via ICAM-1.

Tumor infiltrating neutrophil granulocytes do not only exhibit tumor eliminating functions but also promote tumor progression. We have recently shown that neutrophil granulocytes can serve as linking cells for the adhesion of MDA-MB-468 breast carcinoma cells to pulmonary endothelium. Neutrophil granulocytes but not MDA-MB-468 cells express beta(2)-integrins, the ligands of the intercellular adhesion molecule (ICAM)-1, whereas ICAM-1 is strongly expressed on MDA-MB-468 cells. Consequently, the herein presented study was performed to investigate if this interaction has also an influence on the migratory activity of the tumor cells and whether ICAM-1 signaling plays a role in this process, too. We found that the continuous release of interleukin-8 (IL-8) and GRO-alpha by MDA-MB-468 cells increases the migratory activity of neutrophil granulocytes and attracts these cells towards the tumor cells which enables direct cell-cell interactions. These interactions in turn increase the migratory activity of the tumor cells in an ICAM-1 clustering-dependent mechanism since transfection of the tumor cells with specific siRNA against ICAM-1 abolished the effect. Moreover, ICAM-1 cross-linking on tumor cells induces the phosphorylation of focal adhesion components such as focal adhesion kinase and paxillin via src kinase as well as the activation of the p38 MAPK pathway via Rho kinase in a time-dependent manner. Our results provide evidence that ICAM-1 is coupled to intracellular signaling pathways involved in tumor cell migration. Thus, neutrophil granulocytes can act as modulators of the metastatic capability of tumor cells by ligation of ICAM-1.

Enhanced dendritic cell-induced immune responses mediated by the novel C-type lectin receptor mDCAR1.

The dendritic cell (DC) immunoreceptors (DCIR) and DC-immunoactivating receptors (DCAR) represent a subfamily of cell surface C-type lectin receptors (CLR), whose multifunctional capacities range from classical Ag uptake and immunoregulatory mechanisms to the involvement in DC ontogeny. On the basis of the generation of specific mAbs, we functionally characterized mouse DCAR1 (mDCAR1) as a member of the DCIR/DCAR family. Expression of mDCAR1 was strongly tissue dependent. mDCAR1 expression on DCs was restricted to the CD8(+) DC subset in spleen and thymus and on subpopulations of CD11b(+) myeloid cells in bone marrow and spleen, whereas the molecule was not detectable on both cell types in lymph nodes and peripheral blood. With respect to the function of CLRs as pattern recognition receptors, Ag delivered via mDCAR1 was internalized, was trafficked to early and late endosomes/lysosomes and, as a consequence, induced cellular and humoral responses in vivo even in the absence of CD40 stimulation. Intriguingly, upon triggering mDCAR1, CD8(+) DCs increased the secretion of bioactive IL-12, whereas IL-10 release is markedly reduced, thereby indicating that Ag recognized by mDCAR1 induces enhanced proinflammatory responses. These data indicate that mDCAR1 is a functional receptor on cells of the immune system and provides further insights into the regulation of immune responses by CLRs.

Paving roads for new drugs in oncology.

Low productivity and the escalating costs of drug development have been well documented over the past years. A fraction of new pre-clinical compounds successfully pass experimental test batteries, and less than 10% of these compounds that enter clinical trials ultimately make it to the market. These challenges in the "critical path" of drug development will be discussed for drugs in the field of oncology, regarding the i) the impact of FDA and EMEA guidelines, and ii) microdosing studies/phase 0 trials before a drug enters phase I to III, to inform drug development, compressing drug development timelines and decision-making for continuation into clinical trials. Moreover, this review should embark on i) how to find new key molecules involved in life-and-death decision of a cell, how ii) old drugs will have a revival for new indications, because of novel information for their mode of action, and iii) how the revolutionary advances - high-throughput technologies, gene therapy and the deciphering of the human genome - do have their potential to develop personalized therapy. Therapy has progressed from an age of administering herbal remedies and organ extracts to an era of meticulously planned drug discovery, when pharmaceutical industry was born in a Western understanding. The relevant patents are discussed.