18 research outputs found
GLI1 confers profound phenotypic changes upon LNCaP prostate cancer cells that include the acquisition of a hormone independent state
The GLI (GLI1/GLI2) transcription factors have been implicated in the development and progression of prostate cancer although our understanding of how they actually contribute to the biology of these common tumours is limited. We observed that GLI reporter activity was higher in normal (PNT-2) and tumourigenic (DU145 and PC-3) androgen-independent cells compared to androgen-dependent LNCaP prostate cancer cells and, accordingly, GLI mRNA levels were also elevated. Ectopic expression of GLI1 or the constitutively active NGLI2 mutant induced a distinct cobblestone-like morphology in LNCaP cells that, regarding the former, correlated with increased GLI2 as well as expression of the basal/stem-like markers CD44, beta1-integrin, Np63 and BMI1, and decreased expression of the luminal marker AR (androgen receptor). LNCaP-GLI1 cells were viable in the presence of the AR inhibitor bicalutamide and gene expression profiling revealed that the transcriptome of LNCaP-GLI1 cells was significantly closer to DU145 and PC-3 cells than to control LNCaP-pBP (empty vector) cells, as well as identifying LCN2/NGAL as a highly induced transcript which is associated with hormone independence in breast and prostate cancer. Functionally, LNCaP-GLI1 cells displayed greater clonal growth and were more invasive than control cells but they did not form colonies in soft agar or prostaspheres in suspension suggesting that they do not possess inherent stem cell properties. Moreover, targeted suppression of GLI1 or GLI2 with siRNA did not reverse the transformed phenotype of LNCaP-GLI1 cells nor did double GLI1/GLI2 knockdowns activate AR expression in DU145 or PC-3 cells. As such, early targeting of the GLI oncoproteins may hinder progression to a hormone independent state but a more detailed understanding of the mechanisms that maintain this phenotype is required to determine if their inhibition will enhance the efficacy of anti-hormonal therapy through the induction of a luminal phenotype and increased dependency upon AR function
Aortic stiffness as a marker of cardiac function and myocardial strain in patients undergoing aortic valve replacement
Background: Cardiac function and myocardial strain are affected by cardiac afterload, which is in part due to the
stiffness of the aortic wall. In this study, we hypothesize that aortic pulse wave velocity (PWV) as a marker of aortic
stiffness correlates with conventional clinical and biochemical markers of cardiac function and perioperative
myocardial strain in aortic valve replacement (AVR).
Methods: Patients undergoing AVR for aortic stenosis between June 2010 and August 2012 were recruited for
inclusion in this study. PWV, NYHA class and left ventricular (LV) function were assessed pre-operatively. PWV was
analysed both as a continuous and dichotomous variable according to age-standardized reference values. B-type
natriuretic peptide (BNP) was measured pre-operatively, and at 3 h and 18-24 h after cardiopulmonary bypass (CPB).
NYHA class, leg edema, and LV function were recorded at follow-up (409 Β± 159 days).
Results: Fifty-six patients (16 females) with a mean age of 71 Β± 8.4 years were included, with 50 (89%) patients
completing follow-up. The NYHA class of PWV-norm patients was significantly lower than PWV-high patients both
pre- and post-operatively. Multiple logistic regression also highlighted PWV-cut off as an independent predictor of
NYHA class pre- and post-operatively (OR 8.3, 95%CI [2.27,33.33] and OR 14.44, 95%CI [1.49,139.31] respectively). No
significant relationship was observed between PWV and either LV function or plasma BNP.
Conclusion: In patients undergoing AVR for aortic stenosis, PWV is independently related to pre- and post-operative
NYHA class but not to LV function or BNP. These findings provisionally support the use of perioperative PWV as a
non-invasive marker of clinical functional status, which when used in conjunction with biomarkers of myocardial strain
such as BNP, may provide a holistic functional assessment of patients undergoing aortic valve surgery. However, in
order for PWV assessment to be translated into clinical practice and utilised as more than simply a research tool, further
validation is required in the form of larger prospective studies specifically designed to assess the relationship between
PWV and these functional clinical outcomes
GLI1 Confers Profound Phenotypic Changes upon LNCaP Prostate Cancer Cells That Include the Acquisition of a Hormone Independent State
The GLI (GLI1/GLI2) transcription factors have been implicated in the development
and progression of prostate cancer although our understanding of how they
actually contribute to the biology of these common tumours is limited. We
observed that GLI reporter activity was higher in normal (PNT-2) and
tumourigenic (DU145 and PC-3) androgen-independent cells compared to
androgen-dependent LNCaP prostate cancer cells and, accordingly, GLI mRNA levels
were also elevated. Ectopic expression of GLI1 or the constitutively active
ΞNGLI2 mutant induced a distinct cobblestone-like morphology in LNCaP cells
that, regarding the former, correlated with increased GLI2 as well as expression
of the basal/stem-like markers CD44, Ξ²1-integrin, ΞNp63 and BMI1, and
decreased expression of the luminal marker AR (androgen receptor). LNCaP-GLI1
cells were viable in the presence of the AR inhibitor bicalutamide and gene
expression profiling revealed that the transcriptome of LNCaP-GLI1 cells was
significantly closer to DU145 and PC-3 cells than to control LNCaP-pBP (empty
vector) cells, as well as identifying LCN2/NGAL as a highly induced transcript
which is associated with hormone independence in breast and prostate cancer.
Functionally, LNCaP-GLI1 cells displayed greater clonal growth and were more
invasive than control cells but they did not form colonies in soft agar or
prostaspheres in suspension suggesting that they do not possess inherent stem
cell properties. Moreover, targeted suppression of GLI1 or GLI2 with siRNA did
not reverse the transformed phenotype of LNCaP-GLI1 cells nor did double
GLI1/GLI2 knockdowns activate AR expression in DU145 or PC-3 cells. As such,
early targeting of the GLI oncoproteins may hinder progression to a hormone
independent state but a more detailed understanding of the mechanisms that
maintain this phenotype is required to determine if their inhibition will
enhance the efficacy of anti-hormonal therapy through the induction of a luminal
phenotype and increased dependency upon AR function
Gonadotropins and prostate cancer: revisited.
Luteinizing hormone and follicle-stimulating hormone are called gonadotropins, because they stimulate the gonads β in males the testes and in females the ovaries. They are not necessary for life, but are essential for reproduction. In addition, the association of these hormones with prostate cancer has been the interest of many researchers. Their detection in the human prostate has been investigated using different methods, including immunologic and RT-PCR techniques. In addition, the increasing evidence of paracrine/autocrine functions of the gonadotropic glycoprotein hormones, their allocation to the superfamily of cystine knot growth factors, and luteinizing hormone/chorionic gonadotropin receptor gene expression in non-gonadal tissues led many researchers to investigate intraprostatic glycoprotein hormones and their receptor gene expression. We aim in this review to shed light on the physiology of the gonadotropins and their association with prostate cancer and highlight the future possibilities of their use as targets in treating this disease