Introduction. Matrix metalloproteinase enzymes (MMPs) play important role in inflammation, malignant cell proliferation, invasion and angiogenesis by mediating extracellular matrix degradation. Doxycycline, a synthetic tetracycline, behaves as a MMP inhibitor at a subantimicrobial dose and inhibits tumor cell proliferation, invasion and angiogenesis. The aberrant activity of nuclear factor kappa B (NF-kB) causes activation of MMPs and thereby proliferation and invasion of cancer cells. The aim of this study was to investigate the effects of doxycycline on the expression of MMPs in lipopolysaccharide (LPS)-induced PC3 human prostate cancer cells and the possible role of NF-kB signaling. Material and methods. PC3 cells were incubated with LPS (0.5 µg/mL) for 24 h in the presence or absence of doxycycline (5 µg/mL). The effects of LPS and doxycycline on the expressions of MMP-2, MMP-8, MMP-9, MMP-10, NF-kB/p65, IkB-a, p-IkB-a, IKK-b were examined by Western blotting and immunohistochemistry in PC3 cells. Furthermore, relative proteinase activities of MMP-2 and MMP-9 were determined by gelatin zymography. Results. LPS increased expression and activity of MMP-9 and expression of MMP-8, MMP-10, NF-kB/p65, p-IkB-a, IKK-b and doxycycline down-regulated its effects with the exception of MMP-10 expression. The expression of MMP-2 and IkB-a was affected by neither LPS nor doxycycline. Conclusions. Our findings indicate that doxycycline inhibits the expression of various MMPs and NF-kB signaling may play a role in the regulation of MMPs expression in LPS-induced PC3 human prostate cancer cells.

Discoidin Domain Receptors (DDR1/DDR2) are tyrosine kinase receptors which are activated by collagen. DDR signalling regulates cell migration, proliferation, apoptosis and matrix metalloproteinase (MMP) production. MMPs degrade extracellular matrix (ECM) and play essential role in tumor growth, invasion and metastasis. Nitrogen-containing bisphosphonates (N-BPs) which strongly inhibit osteoclastic activity are commonly used for osteoporosis treatment. They also have MMP inhibitory effect. In this study, we aimed to investigate the effects of zoledronate in PC3 cells and the possible role of DDR signalling and downstream pathways in these inhibitory effects.We studied messenger RNA (mRNA) and protein expressions of MMP-2,-9,-8, DDR1/DDR2 type I procollagen (TIP) and mRNA levels of PCA-1, MMP-13 and DDR-initiated signalling pathway players including K-Ras oncogene, ERK1, JNK1, p38, AKT-1 and BCLX in PC3 cells in the presence or absence of zoledronate (10-100 μM) for 2-3 days.Zoledronate (100 μM) down-regulated DDR1/ DDR2, TIP mRNAs but did not change MMP-13 (collagenase-3) mRNA. However, zoledronate up-regulated MMP-8 (collagenase-2) mRNA. Zoledronate also inhibited mRNA expressions of K-Ras, ERK1, AKT-1, BCLX and PCA-1; but did not change JNK1, p38 mRNA levels. Zoledronate (100 μM) supressed DDR1/DDR2, TIP expressions; and gelatinase (MMP-2/MMP-9) expressions/activities. Conversely, zoledronate up-regulated MMP-8 expression in PC3 cells.Zoledronate down-regulates MMP-2/-9 expressions in PC3 prostate cancer cells. DDR1/DDR2 signalling and DDR-initiated downstream Ras/Raf/ERK and PI3K/AKT pathways may at least partially responsible for MMP inhibitory effect of zoledronate.

Prostate cancer is the second leading cause of morbidity and mortality in males in the Western world. In the present study, LNCaP, which is an androgen receptor-positive and androgen-responsive prostate cancer cell line derived from lymph node metastasis, and DU145, which is an androgen receptor-negative prostate cancer cell line derived from brain metastasis, were investigated. TNFα treatment decreased p105 and p50 expression and R1881 treatment slightly decreased p105 expression but increased p50 expression with or without TNFα induction. As an aggressive prostate cancer cell line, DU145 transfected with six transmembrane protein of prostate (STAMP)1 or STAMP2 was also exposed to TNFα. Western blotting indicated that transfection with either STAMP gene caused a significant increase in NFκB expression following TNFα induction. In addition, following the treatment of LNCaP cells with TNFα, reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed with a panel of apoptosis-related gene primers. The apoptosis-related genes p53, p73, caspase 7 and caspase 9 showed statistically significant increases in expression levels while the expression levels of MDM2 and STAMP1 decreased following TNFα induction. Furthermore, LNCaP cells were transfected with a small interfering NFκB (siNFκB) construct for 1 and 4 days and induced with TNFα for the final 24 h. RT-qPCR amplifications were performed with apoptosis-related gene primers, including p53, caspases and STAMPs. However, no changes in the level of STAMP2 were observed between cells in the presence or absence of TNFα induction or between those transfected or not transfected with siNFκB; however, the level of STAMP1 was significantly decreased by TNFα induction, and significantly increased with siNFκB transfection. Silencing of the survival gene NFκB caused anti-apoptotic STAMP1 expression to increase, which repressed p53, together with MDM2. NFκB silencing had varying effects on a panel of cancer regulatory genes. Therefore, the effective inhibition of NFκB may be critical in providing a targeted pathway for prostate cancer prevention.

Prostate cancer is the second leading reason of morbidity and mortality in men in the Western World. Androgen receptor positive and androgen responsive lymph‐node metastasis of prostate cancer cell line LNCaP was used in all further experiments. Western with NFkB specific antibody was done after TNFa induction at LNCaP cells and a significant increase was taken.LNCaP cells transfected with siNFkB construct for 1,2 and 4 days and induced with TNFa for 24 hours. RNAisolation, cDNA conversion and RT‐PCR amplifications were done with apoptosis related gene primers such as p53, Bcl‐2, STAMP family primers. Chromatine immunoprecipitation (ChIP) assay was done with NFkB specific antibody before and after TNF induction at LNCaP and normal prostate cell line WPMY1. Since both cell lines express STAMP1 and 2, promoter region located NFkB response‐elements were identified and shown with specific primers. However, no change was shown at STAMP2 RT‐PCR amplification at −/+ TNFa native/siNFkB; STAMP1 showed a significant decrease with TNFa induction, while a significant increase with siNFkB.Survival gene NFkB silencing caused anti‐apoptotic STAMP1 increase that repress p53, together with MDM2.Gene silencing differed a panel of cancer regulatory genes.

This study includes the results of a 2-day education project titled "Molecular Biology Laboratory Summer School, MoBiLYO." The project was held at a University Research Center by scientists from Department of Pharmacology and graduate students. The project was composed of introductory lectures, model construction, DNA isolation, polymerase chain reaction (PCR), and gel electrophoresis. The participants were 13-year-old eighth-graders attending primary schools affiliated with Ministry of National Education in urban and rural areas of Izmir, Turkey. The purpose of this study was to introduce basic molecular biology concepts through individually performed experiments such as PCR and gel electrophoresis integrated with creative drama. The students were assessed at the beginning and the end of each project day via mini-tests, experimental and presentation skills evaluation forms. Data showed that students' knowledge about DNA structure and basic molecular biology techniques significantly increased. On the basis of experimental and presentational skills, there was no significant difference between kids from urban and rural schools or between public and boarding public schools, whereas the average score of girls was significantly higher than that of boys. In conclusion, individually performed experiments integrated with creative drama significantly increased students' perception of complex experimental procedures on basic molecular biology concepts. Data suggests that integration of these concepts into the science and technology curriculum of Turkish primary education may support the recruitment of future scientists who can handle rapidly developing genomic techniques that will affect our everyday life.