Evaluation of metastatic potential in prostate carcinoma: an in vivo model.

Prostate cancer is frequently associated with bone metastases, which are in fact the main cause of morbidity and mortality for this tumor. To better investigate this process, animal models of bone and bone marrow metastases need to be developed. However, experimental prostate cancer bone metastases are difficult to be obtained in vivo, and some typical clinical patterns remain irreproducible.

Long-term presence of androgens and anti-androgens modulate EGF-receptor expression and MAP-kinase phosphorylation in androgen receptor-prostate positive cancer cells.

Prostate cancer (Pca) progression from an androgen-dependent to an androgen-independent state occurs in patients who undergo hormonal therapy. There is evidence indicating that deregulation of the epidermal growth factor receptor (EGFR) pathway plays a critical role in this phenomenon. In this study we addressed the question by stably transfecting the androgen receptor (AR) cDNA into the AR-negative Pca cell line DU145 that expresses high levels of EGFR.

Osteopontin enhances the cell proliferation induced by the epidermal growth factor in human prostate cancer cells.

Background: Susceptibility to extracellular matrix and growth factors has been demonstrated to play a critical role in the development of prostate cancer (PCa) metastases. The aim of this study was to elucidate some mechanisms by which stroma controls tumor progression.

Methods: In our study we tested the growth ability of the LNCaP human prostatic cell line in steroid-free culture conditions in response to osteopontin (OPN), a non-collageneous matrix protein, localized in large amounts in the bone.

Prostate cancer cell proliferation is strongly reduced by the epidermal growth factor receptor tyrosine kinase inhibitor ZD1839 in vitro on human cell lines and primary cultures.

Purpose: To investigate the effects of the epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) ZD1839 ('Iressa') on the cellular proliferation of androgen-sensitive and androgen-independent human prostatic cancer cell lines and primary cultures in vitro.

Experimental Design: In this study, we investigated the effects of the quinazoline ZD1839, a potent, selective EGFR-TKI, on the EGFR autophosphorylation and cellular proliferation of androgen-sensitive (ND1, LNCaP, and ALVA-31) and androgen-independent (PC3, DU145, and TSU-Pr1) human prostatic cancer cell lines and 20 primary cultures derived from human prostatic cancer tissue.

Results: EGFR was present and phosphorylated in all cell lines tested.

Bicalutamide dose-dependently inhibits proliferation in human prostatic carcinoma cell lines and primary cultures.

Objective: Androgen antagonists inhibit prostatic cell proliferation in normal and pathological conditions and are useful antitumor agents in prostatic carcinoma (PCa). Bicalutamide (BCLT) is a well-known non-steroidal antiandrogenic agent able to interfere with androgen receptor (AR). We tested the efficacy of BCLT in inhibiting proliferation of human PCa cell lines and of primary cultures from biopsies of PCa patients.

Bombesin-dependent pro-MMP-9 activation in prostatic cancer cells requires beta1 integrin engagement.

Bombesin-like peptides, including the mammalian homologue gastrin-releasing peptide, are highly expressed and secreted by neuroendocrine cells in prostate carcinoma tissues and are likely to be related to the progression of this neoplastic disease. Previously, we demonstrated that bombesin increased migration and protease expression in androgen-independent cells. In this work we show that bombesin is able to activate pro-MMP-9 through a mechanism involving the beta1 integrin subunit.

Vesicle-associated urokinase plasminogen activator promotes invasion in prostate cancer cell lines.

The ability of a cell to modify the extracellular matrix is important in several pathophysiological alterations including tumorigenesis. Cell transformation is accompanied by changes in the surrounding stroma as a result of the action of specific proteases such as the urokinase plasminogen activator (uPA), which has been associated with invasive potential in many tumor types. In this study, we analyzed the release of vesicle-associated uPA by the aggressive prostatic carcinoma cell line PC3 and the implications of this release for the invasive behaviour of prostatic tumor cells.

Culture conditions modulate cell phenotype and cause selection of subpopulations in PC3 prostate cancer cell line.

PC3 cell line contains different cell variants. A first variant grows as spherical multicellular aggregates and shows anchorage-independent growth. A second variant grows as single small rounds and shows anchorage-dependent growth without cell spreading.

Osteoblast-derived TGF-beta1 modulates matrix degrading protease expression and activity in prostate cancer cells.

Tumor progression and metastasis may result in part from the selection of cell clones competent for survival, invasion and growth at secondary sites and characterized by loss of growth inhibitory responses, acquisition of increased adhesiveness and enhanced motility and protease expression. Transforming growth factor-beta1 (TGF-beta1) is produced by osteoblasts (OB) in a latent form and is activated by proteases in a cell-dependent manner. We show here that OB conditioned medium (OB CM) modulates Matrigel invasion of a bone metastatic prostate cancer cell line (PC3) and that this effect is blocked by antibody against TGF-beta1 and by uPA/plasmin inhibitors, suggesting that TGF-beta1 can modulate OB-mediated cell recruitment and that PC3 cells can activate TGF-beta1.

Osteoblast conditioned media contain TGF-beta1 and modulate the migration of prostate tumor cells and their interactions with extracellular matrix components.

Prostate cancers (PRCAs) frequently metastasize to bone. We show here that this process is facilitated by osteoblast-mediated tumor cell recruitment. Transforming growth factor-beta1 (TGF-beta1) is produced by osteoblasts in a latent form and is activated by proteases in a cell-dependent manner.

[The superior median frenulum. Surgical-orthodontic treatment of a recurrence].

The authors illustrate the etiopathogenic factors of the pathology resulting from superior inter-incisal diastema combined with labial frenulum. They point out that it is not possible to solve the examined pathology without an adequate program set out in close cooperation between orthodontist and periodontal surgeon. They also describe a case of relapse after frenectomy carried out before the suitable age for obtaining a final result which is lasting and constant.

Treatment of complicated benign prostatic hyperplasia with LHRH-analogues in aged patients.

The effect of administration of an LHRH-analogue (LHRH-a) was evaluated in 11 patients with benign prostatic hyperplasia (BPH) in whom there were contraindications for surgery. These patients, who already had impaired potency due to age or serious illness, were given 1500 micrograms LHRH-a in the first week and 1200 micrograms from the eighth day onwards. They all improved significantly (P less than 0.

Prolactin unresponsiveness to repeated sulpiride administration in man: recent findings.

The mechanism of prolactin (PRL) unresponsiveness to repeated sulpiride (SUL) administration was investigated by means of two experimental protocols. The first one was carried on in seven male volunteers (age 24 to 34 yr) and consisted of two phases separated by a 5-day interval. In both phases 1 mg/kg of SUL was given im and repeated, 24 h later, together with either placebo (PL, 2 ml saline iv) or TRH (200 micrograms iv).

Radio-immunoassay of salivary progesterone for monitoring ovarian function in female infertility.

Fifty-two women, aged from 25 to 41 years, with infertility due to chronic anovulation were admitted to the study together with 36 age-matched controls with proven ovulatory cycles. Paired plasma (3 ml) and whole unstimulated saliva (10 ml) samples were collected over a 30 day period, starting from the first day of a menstrual bleeding, in patients, and throughout the menstrual cycle, in controls. Salivary progesterone levels, measured in women with infertility, ranged from undetectable values to 16 pmol/l during the first, and from 36 to 98 pmol/l during the second half of the monitoring period.