Progenitor cells are responsible for formation primary epithelial cultures in the prostate epithelial model

Secreting oviduct epithelial cells of Coturnix coturnix japonica (QOEC) and changes to their proteome after nonviral transfection

The quail oviduct (Coturnix c. japonica) is a natural candidate avian bioreactor, while the secretive quail oviduct epithelial cells (QOECs) are potential in vitro producers of recombinant proteins and vaccines. In view of the need for highly performing and transformable cell lines, QOEC may potentially act as an alternative bioreactor platform to the existing ones, for example, to the Chinese hamster ovary. The aim of this work was to characterize QOECs and their response to nucleofection with a nonviral plasmid DNA carrying the human interferon-α 2a gene (hIFNλ2a), in vitro. Primary QOEC cultures from laying quails (10-15 weeks old) were characterized by their proliferation rate, doubling time, and multilineage differentiation. Electroporation to cell nuclei (nucleofection) was used to deliver nonviral plasmid DNA containing a reporter GFP and hIFN under the ovalbumin promoter. The posttransfection analysis included polymerase chain reaction, Western blot analysis, and liquid chromatography coupled to tandem mass spectrometry. QOEC showed a typical epithelial characteristic in a primary 2D monolayer culture system and retained secretive potential up to the first passage. QOEC showed differentiation into osteoblastic lineage after stimulation. The nucleofection mean efficiency was low (2.3%). Differences of up to 10% in the proteomic profiles between nontransfected and transfected QOEC were found, the most important of these were related to the absence of keratins and cell-adhesion proteins in the transfected QOEC. Concluding, with the practical information provided here, QOEC have the potential to serve as an avian secreting cellular platform. QOEC may be further transformed to cell lineage to meet the requirement for a stable, electrocompetent, and transfectable model. The first proteomic comparison of QOEC delivered in this study showed, in the majority, a stable proteome of the nontransfected vs transfected QOEC.

Prostate epithelial stem cells are resistant to apoptosis after α1-antagonist treatment. The impact for BPH patients

INTRODUCTION

Induction of apoptosis in prostatic epithelial cells by doxazosin, terazosin and prazosin has been well documented. However, the biochemical pathways of doxazosin action is still unclear. Aforementioned drugs should lead to decrease of prostate volume, although this effect was never observed in patients suffering from BPH after treatment with α1-antagonists. Probably, it is connected with cancer stem cells' resistance on chemotherapeutic agents. The aim of this study was to compare incidence of apoptosis induced by doxazosin in progenitor and differentiated cells isolated from human prostate epithelium.

MATERIAL AND METHODS

For this purpose tissue specimens were obtained from 10 patients suffering from BPH, the primary cultures of prostate epithelium were established and CD133 MicroBeads sorting was prepared. Both, CD133(+)/CD133(-) co-cultures and CD133(+) cells were incubated with different concentration of doxazosin for 12 h. Cell viability and apoptosis was estimated with Annexin V-FITC.

RESULTS

12 h incubation of CD133(+)/CD133(-) co-cultures with doxazosin resulted in increase of apoptotic cells, while in CD133(+) cultures no changes were observed. Correlation between apoptotic cell number and doxazosin concentration in CD133(+)/ CD133(-) co-cultures group was high (R = 0.99).

CONCLUSION

Doxazosin induced apoptosis in co-cultures of progenitor and differentiated epithelial cells. However, progenitor cells were not susceptible to apoptosis, what can be a reason of treatment failure in BPH patients.

Resistance of stem-like cells from neuroblastoma cell lines to commonly used chemotherapeutic agents

BACKGROUND

Cancer stem cell theory suggests that the presence of tumor initiating stem-like cells in cancers may be responsible for cancer progression and relapse. CD133 cell surface maker expression has been used to identify stem-like cells in cancer cell lines. Our goal was to identify such cells in neuroblastoma cell lines and to study the cytotoxicity of common anticancer drugs for those cells.

MATERIALS AND METHODS

CD133+ cells from SK-N-SH and SK-N-BE cell lines were isolated using magnetic microbeads. Cytotoxicity of four anticancer drugs was studied on CD133+ and CD133- populations. The percentage of live, apoptotic, and dead cells in each population after drug treatment was estimated by MTT and PI/Annexin-binding assays. Western blot analyses were used to identify differences in the expression of kinases.

RESULTS

Eight to 10% of SK-N-SH and 3-5% of SK-N-BE cells were CD133+. These cells were more resistant than CD133- cells to all four chemotherapeutic agents tested in the MTT assay. Decreased apoptosis was observed in CD133+ cells compared to CD133- cells by PI/Annexin V-binding assay. Western blot analysis showed that CD133+ cells expressed less MKP-1. Phosphorylated forms of both ERK and P-38 kinases were expressed at higher levels in CD133+ cells than in CD133- cells.

CONCLUSIONS

This study suggests that CD133+ cells are more resistant to anticancer drugs than CD133- cells. Differences in the expression and phosphorylation of kinases could be partially responsible for this difference. Targeting CD133-expressing cells could be a strategy to develop more effective treatments for neuroblastoma.

Cancer stem cells in prostate adenocarcinoma: a target for new anticancer strategies

Prostate cancer (PC) is major common malignancy in males in most industrialized Western countries, where it is the most commonly diagnosed cancer affecting men after middle age (>50 years). Over 90% of PC patients with incurable disease respond to primary treatment, which consists of intervention to lower serum testosterone. However, the duration of response is short (12-33 months) and in almost all patients, is followed by the emergence of a phenotype resistant to androgen deprivation in therapy (known as hormone or androgen-resistant PC). Considerable research efforts have been directed towards the identification of markers associated with the initiation and progression of PC, yet there is little consensus about the target cell within prostate epithelium that is susceptible to malignant transformation. Stem cells may represent a major target for mutations leading to cancer as their longevity assures continued presence during the long latency between carcinogenic agents exposure and cancer development. Therefore in order to allow the development of more effective treatment strategies for PC, a better understanding of the molecular changes that underlie cancer stem cells is required.

Can conception of prostate cancer stem cells influence treatment dedicated to patients with disseminated disease?

No survival profit has been achieved for patients with disseminated prostate cancer since hormonal therapy was introduced. It is proposed that dissemination of rare prostatic cancer stem cells may lead to metastatic disease and that resistance of these cells to androgen ablation makes them responsible for failure of current treatments. In this paper, we will discuss the significance of the stem cell model for understanding prostate cancer pathogenesis. The concept of prostate cancer as a stem cell disease has the potential to change our view of its treatment in the particular case of disseminated disease. The major cellular target of prostate cancer therapy has to be directed against neoplastic stem cells. The combination of molecular-targeted therapy with the concept of the cancer stem cells should be introduced for the treatment of disseminated prostate cancer. Disseminated prostate cancer must be treated with agents directed toward stem cells, while hormone-therapy must be only an additional treatment leading to the decrease of tumor burden.