The role of cyclins in the development and progression of prostate cancer.

The role of cyclins in hormone-dependent neoplasms is crucial in the development of the disease that is resistant to first-line therapy, as the example of breast cancer shows. However, in prostate cancer, cyclins are studied to a lesser extent. There are some well-described molecular pathways, including cyclins A1 and D1 signaling, however the role of other cyclins, e.g., D2, D3, E, and H, still requires further investigation. Recent studies indicate that cyclins regulate various cellular processes, not only the cell cycle. Furthermore, they remain in cross-talk with many other signaling pathways, e.g., MAPK/ERK, PI3K/Akt, and Notch. The androgen signaling axis, which is pivotal in prostate cancer progression, interferes with cyclin pathways at many levels. This article summarizes current knowledge on the influence of cyclins on prostate cancer progression by describing interactions between the androgen receptor and cyclins, as well as mechanisms underlying the development of resistance to currently used therapies.

Cinnamamide derivatives with 4-hydroxypiperidine moiety enhance effect of doxorubicin to cancer cells and protect cardiomyocytes against drug-induced toxicity through CBR1 inhibition mechanism.

Doxorubicin (DOX) is classified by World Health Organization (WHO) as an essential medicine for cancer. However, its clinical application is limited due to resistance development and cardiotoxicity. Many attempts have been made to address these issues with some focused on finding a potential adjuvant therapy. Recently, inhibition of carbonyl reduction of anthracyclines (ANTs), catalyzed by enzymes from carbonyl reductase (CBR) and aldo-keto reductase (AKR) families, emerged as a potential way to simultaneously bypass cancer resistance and alleviate cardiotoxicity of ANTs. In this context, we evaluated the potential application of l synthetic cinnamic acid derivatives (CA) - 1a (2E)-3-(4- chlorophenyl)-1-(4-hydroxypiperidin-1-yl)prop-2-en-1 and 1b (2E)-1-(4-hydroxypiperidin-1-yl)-3-(2-methylphenyl)prop-2-en-1-one. The tested compounds were found to chemosensitize A549 human lung cancer cell line towards DOX-induced viability reduction and apoptosis, while having no effect in non-cancerous lung fibroblasts. Co-treatment with DOX + 1a/1b significantly inhibited the migration of A549 in a Transwell assay. The addition of 1a/1b alleviated menadione-induced viability reduction in H9c2 rat cardiomyoblast cell line. Accordingly, 1a/1b reduced DOX-induced reactive oxygen species (ROS) generation and increased glutathione levels. The compounds were also found to moderate autophagy process and limit inflammatory response in RAW 264.7 macrophage cell line. Inhibitory properties of the compounds towards CBR1 were simulated by molecular modeling and confirmed in vitro in enzyme inhibition assay with recombinant CBR1 protein. In contrast to 1b, 1a has strong CBR1 inhibition, which correlates well with more profound effect elicited by 1a uniformly throughout the other experiments. Finally, no mutagenic, genotoxic or hepatotoxic activity of the compounds were found. The possible products of cytochrome P450 mediated metabolism of 1a and 1b were also established to evaluate the potential impact of first pass effect. Our results suggest that 1a and 1b are promising candidates for DOX adjuvant therapy that may simultaneously chemosensitize cancer cells and alleviate cardiotoxicity. The higher activity of 1a may be linked with CBR1 inhibition.

Recent Progress in Discovering the Role of Carotenoids and Their Metabolites in Prostatic Physiology and Pathology with a Focus on Prostate Cancer-A Review-Part I: Molecular Mechanisms of Carotenoid Action.

Among the vast variety of plant-derived phytochemicals, the group of carotenoids has continuously been investigated in order to optimize their potential application in the area of dietary intervention and medicine. One organ which has been especially targeted in many of these studies and clinical trials is the human prostate. Without doubt, carotenoids (and their endogenous derivatives-retinoids and other apo-carotenoids) are involved in intra- and intercellular signaling, cell growth and differentiation of prostate tissue. Due to the accumulation of new data on the role of different carotenoids such as lycopene (LC) and ß-carotene (BC) in prostatic physiology and pathology, the present review aims to cover the past ten years of research in this area. Data from experimental studies are presented in the first part of the review, while epidemiological studies are disclosed and discussed in the second part. The objective of this compilation is to emphasize the present state of knowledge regarding the most potent molecular targets of carotenoids and their main metabolites, as well as to propose promising carotenoid agents for the prevention and treatment of prostatic diseases.

Recent Progress in Discovering the Role of Carotenoids and Metabolites in Prostatic Physiology and Pathology-A Review-Part II: Carotenoids in the Human Studies.

Among the vast variety of plant-derived phytochemicals, the group of carotenoids has continuously been investigated in order to optimize their potential application in the area of dietary intervention related to chronic diseases. One organ that has been especially targeted in many of these studies and clinical trials is the human prostate. Without doubt, carotenoids (and their endogenous derivatives-retinoids and apo-carotenoids) are involved in a plethora of intra- and intercellular signaling, cell growth, and differentiation of prostate tissue. Due to the accumulation of new data on the role of different carotenoids, such as lycopene (LYC) and ß-carotene (BC), in prostatic physiology and pathology, the present review aimed to cover the past ten years of research in this regard. Data from experimental studies are presented in the first part of the review, while epidemiological studies are disclosed in this second part. The objective of this compilation was to emphasize the present state of knowledge about the most potent molecular targets of carotenoids, as well as to propose promising carotenoid agents for the prevention and possible treatment of prostatic diseases.

Autophagy modulating agents as chemosensitizers for cisplatin therapy in cancer.

Although cisplatin is one of the most common antineoplastic drug, its successful utilisation in cancer treatment is limited by the drug resistance. Multiple attempts have been made to find potential cisplatin chemosensitisers which would overcome cancer cells resistance thus improving antineoplastic efficacy. Autophagy modulation has become an important area of interest regarding the aforementioned topic. Autophagy is a highly conservative cellular self-digestive process implicated in response to multiple environmental stressors. The high basal level of autophagy is a common phenomenon in cisplatin-resistant cancer cells which is thought to grant survival benefit. However current evidence supports the role of autophagy in either promoting or limiting carcinogenesis depending on the context. This encourages the search of substances modulating the process to alleviate cisplatin resistance. Such a strategy encompasses not only simple autophagy inhibition but also harnessing the process to induce autophagy-dependent cell death. In this paper, we briefly describe the mechanism of cisplatin resistance with a special emphasis on autophagy and we give an extensive literature review of potential substances with cisplatin chemosensitising properties related to autophagy modulation.

Could the kinetin riboside be used to inhibit human prostate cell epithelial-mesenchymal transition?

The epithelial-mesenchymal transition (EMT) is a molecular process connected to higher expression of vimentin and increased activity of transcription factors (Snail, Twist) which restrains E-cadherin. EMT has been linked to prostate cancer metastatic potential, therapy resistance, and poor outcomes. Kinetin riboside (9-(b-dribofuranosyl)-6-furfurylaminopurine, KR) is a naturally occurring cytokinin, which induces apoptosis and shows strong antiproliferative activity against various human cancer cell lines. To establish the effect of KR on human prostate cell lines, expression of, e.g. AR, E-, N-cadherins, Vimentin, Snail, Twist, and MMPs, was analysed at mRNA and protein levels using Western Blot and RT-PCR and/or RQ-PCR techniques. KR inhibited the growth of human prostate cancer cells, but also, to a small extent, of normal cells. This effect depended on the type of the cells and their androgen sensitivity. KR also decreased the level of p-Akt, which takes part in androgen signalling modulation. The antiapoptotic Bcl-2 protein was down-regulated in cancer cell lines, while that of Bax is up-regulated upon KR exposure. KR contributed to re-expression of the E-cadherin as well as to significant changes in cell migration. Taken together, our results indicate for the first time that KR can be proposed as a factor for signalling pathways regulation that participates in the inhibition of development of aggressive forms of prostate cancer, and may alter the approach to therapeutic interventions. We propose KR as a potent inhibitor of EMT in human prostate cells.