ZONAB promotes proliferation and represses differentiation of proximal tubule epithelial cells.

Epithelial polarization modulates gene expression. The transcription factor zonula occludens 1 (ZO-1)-associated nucleic acid binding protein (ZONAB) can shuttle between tight junctions and nuclei, promoting cell proliferation and expression of cyclin D1 and proliferating cell nuclear antigen (PCNA), but whether it also represses epithelial differentiation is unknown. Here, during mouse kidney ontogeny and polarization of proximal tubular cells (OK cells), ZONAB and PCNA levels decreased in parallel and inversely correlated with increasing apical differentiation, reflected by expression of megalin/cubilin, maturation of the brush border, and extension of the primary cilium. Conversely, ZONAB reexpression and loss of apical differentiation markers provided a signature for renal clear cell carcinoma. In confluent OK cells, ZONAB overexpression increased proliferation and PCNA while repressing megalin/cubilin expression and impairing differentiation of the brush border and primary cilium. Reporter and chromatin immunoprecipitation assays demonstrated that megalin and cubilin are ZONAB target genes. Sparsely plated OK cells formed small islands composed of distinct populations: Cells on the periphery, which lacked external tight junctions, strongly expressed nuclear ZONAB, proliferated, and failed to differentiate; central cells, surrounded by continuous junctions, lost nuclear ZONAB, stopped proliferating, and engaged in apical differentiation. Taken together, these data suggest that ZONAB is an important component of the mechanisms that sense epithelial density and participates in the complex transcriptional networks that regulate the switch between proliferation and differentiation.

Empatia e ser-para-outrem: Husserl e Sartre perante o problema da intersubjectividade / Empathy and being-to-another: Husserl and Sartre before the intersubjectivity issue

O artigo propõe a discussão sobre o problema da intersubjetividade em Husserl e Sartre. São examinadas a teoria sartriana do être-pour-autrui, do ser-para-outrem, e a teoria husserliana da Einfühlung, da “intropatia” (ou, para utilizar uma expressão mais corrente, da empa­tia), enquanto forma de fundo da experiência de um outro sujeito. O autor analisa, em Husserl, a existência de um “solipsismo” metodológico destinado a mostrar que o sentido da subjectividade é a intersubjectividade comunitária, na empatia e na comunicação. Em Sartre, ao invés, constata-se uma afirmação inicial de outrem como a inul­trapassável presença de uma liberdade que aniquila a minha própria, deixando-me ver nela, apenas, a minha própria imagem como objecto, e que para sempre me enclausura numa som­bria solidão.(AU)

This article discusses the intersubjectivity issue in Husserl and Sartre. It goes over Sartre’s être-pour-autrui (being-to-another) theory and Husserl’s Einfühlung, of “intropathy” theory (or the empathy theory, to use a term of current use), as background form of another subject’s experience. As for Husserl’s thoughts, the author examines the existence of a methodological “solipsism”, meant to demonstrate the meaning of subjectivity is communitarian intersubjectivity, in both empathy and communication. In Sartre’s writings, however, there is an opening affirmative of another with the unsurpassable presence of a liberty which annihilates my own, allowing me to see in it just my own image as an object, and which, encapsules me forever in gloomy loneliness.(AU)

Empatia e ser-para-outrem: Husserl e Sartre perante o problema da intersubjectividade / Empathy and being-to-another: Husserl and Sartre before the intersubjectivity issue

O artigo propõe a discussão sobre o problema da intersubjetividade em Husserl e Sartre. São examinadas a teoria sartriana do être-pour-autrui, do ser-para-outrem, e a teoria husserliana da Einfühlung, da “intropatia” (ou, para utilizar uma expressão mais corrente, da empa­tia), enquanto forma de fundo da experiência de um outro sujeito. O autor analisa, em Husserl, a existência de um “solipsismo” metodológico destinado a mostrar que o sentido da subjectividade é a intersubjectividade comunitária, na empatia e na comunicação. Em Sartre, ao invés, constata-se uma afirmação inicial de outrem como a inul­trapassável presença de uma liberdade que aniquila a minha própria, deixando-me ver nela, apenas, a minha própria imagem como objecto, e que para sempre me enclausura numa som­bria solidão

This article discusses the intersubjectivity issue in Husserl and Sartre. It goes over Sartre’s être-pour-autrui (being-to-another) theory and Husserl’s Einfühlung, of “intropathy” theory (or the empathy theory, to use a term of current use), as background form of another subject’s experience. As for Husserl’s thoughts, the author examines the existence of a methodological “solipsism”, meant to demonstrate the meaning of subjectivity is communitarian intersubjectivity, in both empathy and communication. In Sartre’s writings, however, there is an opening affirmative of another with the unsurpassable presence of a liberty which annihilates my own, allowing me to see in it just my own image as an object, and which, encapsules me forever in gloomy loneliness

Identification of tumor-associated antigens by large-scale analysis of genes expressed in human colorectal cancer.

Despite the high prevalence of colon cancer in the world and the great interest in targeted anti-cancer therapy, only few tumor-specific gene products have been identified that could serve as targets for the immunological treatment of colorectal cancers. The aim of our study was therefore to identify frequently expressed colon cancer-specific antigens. We performed a large-scale analysis of genes expressed in normal colon and colon cancer tissues isolated from colorectal cancer patients using massively parallel signal sequencing (MPSS). Candidates were additionally subjected to experimental evaluation by semi-quantitative RT-PCR on a cohort of colorectal cancer patients. From a pool of more than 6000 genes identified unambiguously in the analysis, we found 2124 genes that were selectively expressed in colon cancer tissue and 147 genes that were differentially expressed to a significant degree between normal and cancer cells. Differential expression of many genes was confirmed by RT-PCR on a cohort of patients. Despite the fact that deregulated genes were involved in many different cellular pathways, we found that genes expressed in the extracellular space were significantly over-represented in colorectal cancer. Strikingly, we identified a transcript from a chromosome X-linked member of the human endogenous retrovirus (HERV) H family that was frequently and selectively expressed in colon cancer but not in normal tissues. Our data suggest that this sequence should be considered as a target of immunological interventions against colorectal cancer.

Subjectividade e intersubjectividade: Sartre perante Hegel e Husserl / xxx

Neste artigo, examino a teoria sartreana do conflito. Ela é a tese fundamental de Sartre no que se refere à descrição fenomenológica das relações interpessoais. Sublinho as dívidas de Sartre relativamente a Hegel e a Husserl, e sigo a evolução da tese sartreana desde La Transcendance de l’Ego até L’Être et le Néant. O artigo procura mostrar alguns dos problemas da Teoria do Conflito de Sartre. Primeiramente, há um problema no que diz respeito à maneira como Sartre focaliza suas descrições exclusivamente no relacionamento “face-a-face”. Em segundo lugar, há um outro problema no modo como Sartre tenta descrever a consciência de um alter-ego como um tipo de consciência de si ou de autoconsciência (a consciência de um alter-ego é, para Sartre, o mesmo que a consciência de si próprio como um “ser-para-o-outrem”), em vez de uma intenção direta no plano pré-reflexivo. Termino com uma apreciação negativa da tese de Sartre.(AU)

In this paper, I examine conflict theory as the fundamental thesis of Sartre’s phenomenological description of interpersonal relationships. I stress Sartre’s debts toward Hegel and Husserl, and I follow his evolution from La transcendance de l’ego till L’être et le néant. I intend to show several problems in Sartre’s conflict thesis. First, there is a problem regarding the way Sartre focuses his descriptions exclusively on the face-to-face relationship. Second, there is another problem regarding Sartre’s attempt to describe the relation to an alter ego as a kind of self-consciousness (consciousness of an alter ego is the same as self-consciousness as a “being-for-other”), instead of a direct intention in the pre-reflexive area. I finish with a negative appraisal of Sartre’s thesis.(AU)

En este articulo, examino la teoría del conflicto de Sartre. Esta es la tesis fundamental de Sartre en lo que se refire a la descripción fenomenológica de las relaciones interpersonales. Dando enfasis en las influencias de Hegel y Husserl sobre Sartre, sigo la evolución de la tesis sartreana desde La Transcendance de l’Ego hasta L’Être et le Néant. El articulo apresenta algunos de los problemas de la Teoria del Conflicto de Sartre. En primer lugar tenemos el problema de la manera como Sartre foca sus descripciones en la relación de uno a otro. En segundo lugar, tenemos el problema de la descripción de la consciência de un alter-ego como una consciência de si o autoconsciência (la consciência de un alter-ego es, para Sartre, lo mismo que la consciência de si-mismo como un “serpara- el-otro”). El texto finda con la apreciación negativa de la tesis de Sartre.(AU)

Immunogenicity of the carcinoembryonic antigen derived peptide 694 in HLA-A2 healthy donors and colorectal carcinoma patients.

Carcinoembryonic antigen (CEACAM5) is commonly overexpressed in human colon cancer. Several antigenic peptides recognized by cytolytic CD8+ T-cells have been identified and used in colon cancer phase-I vaccination clinical trials. The HLA-A*0201-binding CEA(694-702) peptide was recently isolated from acid eluted MHC-I associated peptides from a human colon tumor cell line. However, the immunogenicity of this peptide in humans remains unknown. We found that the peptide CEA(694-702) binds weakly to HLA-A*0201 molecules and is ineffective at inducing specific CD8+ T-cell responses in healthy donors. Immunogenic-altered peptide ligands with increased affinity for HLA-A*0201 were identified. Importantly, the elicited cytolytic T lymphocyte (CTL) lines and clones cross-reacted with the wild-type CEA(694-702) peptide. Tumor cells expressing CEA were recognized in a peptide and HLA-A*0201 restricted fashion, but high-CEA expression levels appear to be required for CTL recognition. Finally, CEA-specific T-cell precursors could be readily expanded by in vitro stimulation of peripheral blood mononuclear cell (PBMC) from colon cancer patients with altered CEA peptide. However, the CEA-specific CD8+ T-cell clones derived from cancer patients revealed low-functional avidity and impaired tumor-cell recognition. Together, using T-cells to demonstrate the processing and presentation of the peptide CEA694-702, we were able to corroborate its presentation by tumor cells. However, the low avidity of the specific CTLs generated from cancer patients as well as the high-antigen expression levels required for CTL recognition pose serious concerns for the use of CEA694-702 in cancer immunotherapy.

Induction of multiple CD8+ T cell responses against the inducible Hsp70 employing an Hsp70 oligoepitope peptide.

The inducible heat shock protein Hsp70 has been described as a tumour antigen being frequently overexpressed in tumours of various histologic origins, with a role in tumourigenicity, as a critical event in tumour progression. A strategy to enhance the immune response to an antigen is the identification of multiple epitopes and the induction of a polyspecific response. Applied to tumour vaccination, such a polyspecific response should lead to a more robust antitumour efficacy. The long peptide Hsp70380-402 encompasses three nonamer peptides with a high affinity for HLA-A *0201. In a previous paper, we have shown that two of these nonamer peptides, p391 and p393, can raise CTL to recognize tumour cells overexpressing Hsp70. In the present paper, we demonstrate that the third nonamer peptide, p380, is a new epitope efficient in raising an antitumour immune response. The p380-402 polypeptide was able to induce an immune response against each of the three constituent epitopes both in vivo in HLA-A *0201 transgenic mice and in vitro with human PBMC. This polypeptide therefore constitutes an interesting candidate for the induction of multiple HLA-A *0201-restricted anti-Hsp70 antitumour CTL responses.

Molecular and immunological evaluation of the expression of cancer/testis gene products in human colorectal cancer.

Tumor-specific gene products, such as cancer/testis (CT) antigens, constitute promising targets for the development of T cell vaccines. Whereas CT antigens are frequently expressed in melanoma, their expression in colorectal cancers (CRC) remains poorly characterized. Here, we have studied the expression of the CT antigens MAGE-A3, MAGE-A4, MAGE-A10, NY-ESO-1 and SSX2 in CRC because of the presence of well-described HLA-A2-restricted epitopes in their sequences. Our analyses of 41 primary CRC and 14 metastatic liver lesions confirmed the low frequency of expression of these CT antigens. No increased expression frequencies were observed in metastatic tumors compared to primary tumors. Histological analyses of CRC samples revealed heterogeneous expression of individual CT antigens. Finally, evidence of a naturally acquired CT antigen-specific CD8(+) T cell response could be demonstrated. These results show that the expression of CT antigens in a subset of CRC patients induces readily detectable T cell responses.

STEAP, a prostate tumor antigen, is a target of human CD8+ T cells.

STEAP is a recently identified protein shown to be particularly overexpressed in prostate cancer and also present in numerous human cancer cell lines from prostate, pancreas, colon, breast, testicular, cervical, bladder and ovarian carcinoma, acute lymphocytic leukemia and Ewing sarcoma. This expression profile renders STEAP an appealing candidate for broad cancer immunotherapy. In order to investigate if STEAP is a tumor antigen that can be targeted by specific CD8(+) T cells, we identified two high affinity HLA-A*0201 restricted peptides (STEAP(86-94) and STEAP(262-270)). These peptides were immunogenic in vivo in HLA-A*0201 transgenic HHD mice. Peptide specific murine CD8 T cells recognized COS-7 cells co-transfected with HHD (HLA-A*0201) and STEAP cDNA constructs and also HLA-A*0201(+) STEAP(+) human tumor cells. Furthermore, STEAP(86-94) and STEAP(262-270) stimulated specific CD8(+) T cells from HLA-A*0201(+) healthy donors, and these peptide specific CD8(+) T cells recognized STEAP positive human tumor cells in an HLA-A*0201-restricted manner. Importantly, STEAP(86-94)-specific T cells were detected and reactive in the peripheral blood mononuclear cells in NSCLC and prostate cancer patients ex vivo. These results show that STEAP can be a target of anti-tumor CD8(+) T cells and that STEAP peptides can be used for a broad-spectrum-tumor immunotherapy.

Inducible Hsp70 as target of anticancer immunotherapy: Identification of HLA-A*0201-restricted epitopes.

The design of a broad application tumor vaccine requires the identification of tumor antigens expressed in a majority of tumors of various origins. We questioned whether the major stress-inducible heat shock protein Hsp70 (also known as Hsp72), a protein frequently overexpressed in human tumors of various histological origins, but not in most physiological normal tissues, constitutes a tumor antigen. We selected the p391 and p393 peptides from the sequence of the human inducible Hsp70 that had a high affinity for HLA-A*0201. These peptides were able to trigger a CTL response in vivo in HLA-A*0201-transgenic HHD mice and in vitro in HLA-A*0201+ healthy donors. p391- and p393-specific human and murine CTL recognized human tumor cells overexpressing Hsp70 in a HLA-A*0201-restricted manner. Tetramer analysis of TILs showed that these Hsp70 epitopes are targets of an immune response in many HLA-A*0201+ breast cancer patients. Hsp70 is a tumor antigen and the Hsp70-derived peptides p391 and p393 could be used to raise a cytotoxic response against tumors of various origins.

EphA2 as target of anticancer immunotherapy: identification of HLA-A*0201-restricted epitopes.

EphA2 (Eck) is a tyrosine kinase receptor that is overexpressed in several human cancers such as breast, colon, lung, prostate, gastric carcinoma, and metastatic melanoma but not in nonmalignant counterparts. To validate EphA2 as a tumor antigen recognized by CD8+ T lymphocytes, we used reverse immunology approach to identify HLA-A*0201-restricted epitopes. Peptides bearing the HLA-A*0201-specific anchor motifs were analyzed for their capacity to bind and stabilize the HLA-A*0201 molecules. Two peptides, EphA2(58) and EphA2(550), with a high affinity for HLA-A*0201 were selected. Both peptides were immunogenic in the HLA-A*0201-transgenic HHD mice. Interestingly, peptide-specific murine CTLs cell lines responded to COS-7 cells coexpressing HLA-A*0201 and EphA2 and to EphA2-positive human tumor cells of various origin (renal cell, lung, and colon carcinoma and sarcoma). This demonstrates that EphA2(58) and EphA2(550) are naturally processed from endogenous EphA2. In addition, EphA2(58) and EphA2(550) stimulated specific CD8(+) T cells from healthy donor peripheral blood mononuclear cells. These T cells recognized EphA2-positive human tumor cells in an HLA-A*0201-restricted manner. Interestingly, EphA2-specific CD8+ T cells were detected in the peripheral blood mononuclear cells of prostate cancer patients. These results show for the first time that EphA2 is a tumor rejection antigen and lead us to propose EphA2(58) and EphA2(550) peptides for a broad-spectrum-tumor immunotherapy.