Dendritic cells regulate T-cell deattachment through the integrin-interacting protein CYTIP.

When T cells are primed by dendritic cells (DCs) to initiate antigen-specific immune responses screening for matching antigen receptor-MHC/peptide pairs takes place in DC-T-cell conjugates. For an immune response DC-T-cell conjugates formed during priming events need to dissolve. Although detailed knowledge on molecules involved in the conjugate formation is available, dissolving of them has not been considered to be an active process.

Small G-protein RhoE is underexpressed in prostate cancer and induces cell cycle arrest and apoptosis.

Background: RhoE/Rnd3, a recently described novel member of the Rho GTPases family, was discussed as a possible antagonist of the RhoA protein that stimulates cell cycle progression and is overexpressed and/or overactivated in prostate cancer. We investigated the expression of RhoE and its role in cell cycle regulation and apoptosis in the human prostate.

Methods: RhoE expression in cell lines and tissue specimens was assessed by immunoblot analysis, real-time PCR (RT-PCR), and immunohistochemistry.

Long-term androgen-ablation causes increased resistance to PI3K/Akt pathway inhibition in prostate cancer cells.

Background: In advanced stages of prostate cancer, the phosphatidylinositol-3' kinase (PI3K)/Akt signaling cascade, one of the major survival pathways in the cell, is frequently constitutively activated due to mutation or loss of the tumor suppressor protein phosphatase and tensin homolog deleted on chromosome 10 (PTEN). Using cell culture models representing different tumor stages, we explored the effect of inhibition of this survival pathway on the induction of apoptosis.

Methods: Inhibition of the survival kinase Akt and induction of apoptosis was analyzed in androgen-insensitive DU145 and PC-3 cells, in androgen-responsive LNCaP, and in androgen-independent long-term androgen-ablated LNCaP-abl cells representing therapy-resistant prostate cancer cells.

Androgen receptor regulation by physiological concentrations of the isoflavonoid genistein in androgen-dependent LNCaP cells is mediated by estrogen receptor beta.

Objectives: Isoflavonoids are discussed for use in chemoprevention and treatment of prostate cancer. We investigated the potential of genistein to modulate androgen receptor (AR) expression and transcriptional activity in the human androgen-sensitive prostate cancer cell line LNCaP.

Materials And Methods: AR expression at mRNA and protein level was analyzed by real-time RT-PCR and immunoblot, respectively.

Acquisition of agonistic properties of nonsteroidal antiandrogens after treatment with oncostatin M in prostate cancer cells.

Purpose: Interleukin-6 (IL-6), a proinflammatory cytokine the serum andtissue levels of which are elevated in prostate cancer patients, activates the androgen receptor (AR) in a ligand-independent and synergistic manner. Oncostatin M (OSM) is an IL-6 type cytokine that regulates the growth of prostate cancer cells in a paracrine fashion. The present study was designed to investigate the regulation of AR expression and function by OSM, as well as the efficacy of the nonsteroidal antiandrogens hydroxyflutamide and bicalutamide in the inhibition of AR-mediated signal transduction.