The neutrophil-lymphocyte ratio has a role in predicting the effectiveness of nivolumab in Japanese patients with metastatic renal cell carcinoma: a multi-institutional retrospective study.

BACKGROUND: The neutrophil-lymphocyte ratio (NLR) is a well-known prognostic marker in various cancers. However, its role as a predictive marker for the effectiveness of nivolumab in patients with metastatic RCC (mRCC) remains unclear. We evaluated the relationships between the NLR and progression-free survival (PFS) or overall survival (OS) in mRCC patients treated with nivolumab. METHODS: The data of 52 mRCC patients who received nivolumab therapy were collected from seven institutes and evaluated. The median follow-up period from treatment with nivolumab was 25.2 months (IQR 15.5-33.2). RESULTS: The median duration of nivolumab therapy was 7.1 months (IQR 2.9-24.4). The objective response rate was 25% and the 1- and 2-year PFS rates were 46.2 and 25.2%, respectively. The median NLR values at baseline and 4 weeks were 3.7 (IQR 2.7-5.1) and 3.3 (IQR 2.4-5.7), respectively. In the multivariate analysis, an NLR of ≥3 at 4 weeks was an independent predictor of PFS (P = 0.013) and OS (P = 0.034). The 1-year PFS of patients with an NLR of < 3 at 4 weeks was better than that of those with an NLR of ≥3 (75% versus 29%, P = 0.011). The 1-year OS of patients with an NLR of < 3 at 4 weeks was also better than that of those with an NLR of ≥3 (95% versus 71%, P = 0.020). CONCLUSIONS: Although the baseline NLR was not associated with PFS or OS, an NLR of ≥3 at 4 weeks after the initiation of therapy might be a robust predictor of poor PFS and OS in mRCC patients undergoing sequential treatment with nivolumab.

CT and MRI findings of a stromal tumour of uncertain malignant potential of the prostate.

Cystic neoplasms arising from the prostate are rare, and stromal tumours of uncertain malignant potential and the spectrum of cystic epithelial tumours of the prostate are the major differential diagnoses of a cystic prostatic neoplasm. We report a case of a stromal tumour of uncertain malignant potential, which showed a multilocular cystic mass with some solid components. The solid component of the tumour did not show substantial diffusion restriction and uptake of 18F-FDG-PET, and this could be the critical finding suggesting a stromal tumour of uncertain malignant potential rather than a malignant cystic epithelial tumour.

SEMA3C drives cancer growth by transactivating multiple receptor tyrosine kinases via Plexin B1.

Growth factor receptor tyrosine kinase (RTK) pathway activation is a key mechanism for mediating cancer growth, survival, and treatment resistance. Cognate ligands play crucial roles in autocrine or paracrine stimulation of these RTK pathways. Here, we show SEMA3C drives activation of multiple RTKs including EGFR, ErbB2, and MET in a cognate ligand-independent manner via Plexin B1. SEMA3C expression levels increase in castration-resistant prostate cancer (CRPC), where it functions to promote cancer cell growth and resistance to androgen receptor pathway inhibition. SEMA3C inhibition delays CRPC and enzalutamide-resistant progression. Plexin B1 sema domain-containing:Fc fusion proteins suppress RTK signaling and cell growth and inhibit CRPC progression of LNCaP xenografts post-castration in vivo SEMA3C inhibition represents a novel therapeutic strategy for treatment of advanced prostate cancer.

Predicting disease progression from short biomarker series using expert advice algorithm.

Well-trained clinicians may be able to provide diagnosis and prognosis from very short biomarker series using information and experience gained from previous patients. Although mathematical methods can potentially help clinicians to predict the progression of diseases, there is no method so far that estimates the patient state from very short time-series of a biomarker for making diagnosis and/or prognosis by employing the information of previous patients. Here, we propose a mathematical framework for integrating other patients' datasets to infer and predict the state of the disease in the current patient based on their short history. We extend a machine-learning framework of "prediction with expert advice" to deal with unstable dynamics. We construct this mathematical framework by combining expert advice with a mathematical model of prostate cancer. Our model predicted well the individual biomarker series of patients with prostate cancer that are used as clinical samples.

Oxidized LDL (oxLDL) activates the angiotensin II type 1 receptor by binding to the lectin-like oxLDL receptor.

The angiotensin II type 1 receptor (AT1) is a 7-transmembrane domain GPCR that when activated by its ligand angiotensin II, generates signaling events promoting vascular dysfunction and the development of cardiovascular disease. Here, we show that the single-transmembrane oxidized LDL (oxLDL) receptor (LOX-1) resides in proximity to AT1 on cell-surface membranes and that binding of oxLDL to LOX-1 can allosterically activate AT1-dependent signaling events. oxLDL-induced signaling events in human vascular endothelial cells were abolished by knockdown of AT1 and inhibited by AT1 blockade (ARB). oxLDL increased cytosolic G protein by 350% in Chinese hamster ovary (CHO) cells with genetically induced expression of AT1 and LOX-1, whereas little increase was observed in CHO cells expressing only LOX-1. Immunoprecipitation and in situ proximity ligation assay (PLA) assays in CHO cells revealed the presence of cell-surface complexes involving LOX-1 and AT1. Chimeric analysis showed that oxLDL-induced AT1 signaling events are mediated via interactions between the intracellular domain of LOX-1 and AT1 that activate AT1. oxLDL-induced impairment of endothelium-dependent vascular relaxation of vascular ring from mouse thoracic aorta was abolished by ARB or genetic deletion of AT1. These findings reveal a novel pathway for AT1 activation and suggest a new mechanism whereby oxLDL may be promoting risk for cardiovascular disease.

En bloc vascular resection for the treatment of borderline resectable pancreatic head carcinoma.

Borderline resectable (BR) pancreatic head carcinoma (PhC) is an advanced disease, presenting with infiltration of major vessels. Major vascular resection (VR), particularly arterial resection, to achieve microscopic no residual tumor (R0) is a controversial approach, due to the potential complications. In this study, we aimed to clarify the benefit of en bloc R0 resection with VR for PhC by retrospectively evaluating 78 PhC patients who underwent pancreatoduodenectomy at our institute. The patients were divided into 4 groups as follows: R, resectable (n=20); BR-V, BR involving the superior mesenteric vein or portal vein (PV) (n=28); BR-SMA, BR involving the superior mesenteric artery (n=21); and BR-HA, BR involving the hepatic artery (n=9). In total, 65 patients underwent VR, with 63, 21 and 9 patients undergoing PV, SMA and HA resection, respectively. The R0 rates were as follows: R group, 85%; BR-V, 82%; BR-SMA, 71%; and BR-HA, 33%. The median survival time and 5-year survival rate for R0 resection were 31 months and 25% in the R group, 22 months and 28% in the BR-V group, 17 months and 27% in the BR-SMA group and 10 months and 0% in the BR-HA group, respectively. The prognosis was comparable among the BR-V, BR-SMA and R groups, but was significantly poorer in the BR-HA group. In total, 5 patients (6.4%) died perioperatively (4 from postoperative hemorrhage and 1 from suffocation due to failure of expectoration, without pneumonia or asthma). Of the 4 patients who succumbed to hemorrhage, 3 had undergone arterial resection. Therefore, en bloc resection with major VR for R0 may be suitable for BR-V and BR-SMA PhC patients.

Mid-term outcome of permanent prostate iodine-125 brachytherapy in Japanese patients.

OBJECTIVES: To analyze mid-term oncological outcomes of low-dose rate brachytherapy in Japanese patients. METHODS: Between 2003 and 2010, 604 consecutive patients with clinically localized prostate cancer were treated with low-dose rate brachytherapy at Jikei University Hospital in Tokyo, Japan. Median follow up was 48 months. Of these patients, 260 (43%) were treated with neoadjuvant therapy, 45 (7.5%) with adjuvant hormonal therapy and 75 (12.4%) with supplemental external beam radiation therapy. Biochemical recurrence was defined as the prostate-specific antigen nadir plus 2 ng/mL. RESULTS: Of the 604 patients, 219 (36.2%) were low risk, 361 (59.8%) were intermediate risk and 24 (4.0%) had high-risk disease. The median biologically effective dose was 174.4 Gy2. At 8 years, biochemical recurrence-free survival, cancer-specific survival, and overall survival were 82.2%, 100% and 95.6%, respectively. Biochemical recurrence-free survival at 8 years was 89.9%, 79.4% and 52.5%, for the low-, intermediate-, and high-risk groups, respectively. Biochemical recurrence-free survival for the high-risk group was significantly lower than the low- and intermediate-risk groups (P < 0.001). Biochemical recurrence-free survival did not differ significantly by biologically effective dose stratification. In multivariate analysis, younger age (P = 0.045), higher prostate-specific antigen (P = 0.004), higher Gleason score (P = 0.006) and higher clinical T stage (P = 0.008) were significant covariates associated with biochemical recurrence. The addition of hormonal therapy or external beam radiation therapy was associated with significantly better outcomes than low-dose rate brachytherapy monotherapy (P = 0.0021 and 0.010). Just four patients experienced G3 genitourinary or gastrointestinal toxicity. CONCLUSIONS: Low-dose rate brachytherapy results in excellent mid-term oncological outcomes and acceptable toxicity in Japanese patients. In our experience, biologically effective dose does not represent a significant predictor for biochemical recurrence.

[The prevalence of hypertension after adrenalectomy in patients with primary aldosteronism].

The cure rate of hypertension after surgery for primary aldosteronism (PA) was assessed in a single institution. In the present study, we studied the risk factors on the cure rate of hypertension after surgery in patients with PA. Thirty-five patients who underwent surgery for PA between January 2004 and December 2009, with a follow-up time of 1 year or longer were studied. The mean age at surgery was 50.7 years old. The male to female ratio was 24 : 11. Factors confounding the cure rate of hypertension after surgery were analyzed using the univariate and the multivariate analysis. Nineteen (54%) of the 35 patients were completely cured after surgery. In most cases, a complete cure was seen within 1 month after surgery. At 1 year after surgery, the dose of medication for hypertension could be decreased in 11 (13%) of the 16 non cured patients. Although hypertension in patients with PA may be curable by surgery, the cure rate of hypertension after surgery has been reported to be from 16 to 67%. In the present study, age, gender, preoperative serum creatinine, the period of hypertension, the number of medications for hypertension, and family history for hypertension were significant in the univariate analysis for the cure rate of hypertension (persistent hypertension) after surgery. Multivariate analysis showed that the age of 55 years old or older was a significant predictor for non-curable hypertension after surgery. Our result suggests that earlier surgery may contribute to a better outcome on the cure rate of postoperative hypertension in patients with PA.

Effect of tablets with a combination of telmisartan and amlodipine on patients with hypertension: the Cotalo study.

Fixed-dose combination (FDC) therapy with telmisartan 40 mg+amlodipine 5 mg (T40/A5) is expected to achieve tight blood pressure (BP) control because of the strong efficacy and long half-life of each drug. The aims of this study were to evaluate the 24-h antihypertensive efficacy of T40/A5 FDC therapy and to explore differences that may arise owing to different administration times in Japanese patients whose hypertension was not controlled by 5 mg of amlodipine per day. In this randomized clinical trial, 44 patients who had been taking amlodipine 5 mg per day and did not achieve their optimal BP target were enrolled (mean age: 67.8±10.2 years). The subjects were then randomly assigned to a T40/A5 morning or evening administration group (22 patients per group). At baseline and 8 weeks after randomization, we evaluated clinical BP and various laboratory values and performed ambulatory BP monitoring (ABPM). Clinical and mean BP evaluated with ABPM at 8 weeks (24 h, daytime, nighttime and early morning) were significantly decreased compared with BP at baseline. There were no significant differences in the diurnal BP profile change from baseline to 8 weeks between subjects in the morning and evening administration groups. There were also no significant differences in the diurnal BP profile change from baseline to 8 weeks between subjects with or without metabolic syndrome. We conclude that T40/A5 FDC therapy significantly decreased the 24-h mean and clinical BP, independent of administration time, in patients whose hypertension was not controlled by 5 mg of amlodipine.

Expression of ERG oncoprotein is associated with a less aggressive tumor phenotype in Japanese prostate cancer patients.

To investigate and characterize ERG oncoprotein expression in Japanese patients with prostate cancer (PCa), we evaluated 92 index tumors from Japanese patients who had undergone radical prostatectomy for PCa, using an antibody-based detection method to determine ERG expression. Expression status was compared with clinicopathological findings including patient age, body mass index and preoperative prostate-specific antigen (PSA) levels, specimen Gleason score, pathological stage, positive surgical margin, size of index tumor, prostatic volume, zonal origin of index tumor and biochemical failure. Overall, ERG protein was expressed in 16.3% (15/92) of the index tumors, but not in benign glands. Younger patient age, lower Gleason score and negative surgical margins were found to be independently associated with its expression in the multivariate analysis (P= 0.015, 0.003 and 0.038, respectively). ERG expression was not associated with biochemical failure. Though not statistically significant, ERG expression was more frequently observed in peripheral zone than in transition zone cancers (28.2% vs 10%, respectively). In conclusion, ERG protein was less frequently expressed in this Japanese PCa cohort compared with Western reports. ERG expression was associated with a less aggressive tumor phenotype, and its biological significance needs to be further investigated.

Transient receptor potential A1 receptor-mediated neural cross-talk and afferent sensitization induced by oxidative stress: implication for the pathogenesis of interstitial cystitis/bladder pain syndrome.

Although the pathogenesis of interstitial cystitis/bladder pain syndrome remains unknown, there is a significant correlation of interstitial cystitis/bladder pain syndrome with other chronic pain disorders, such as irritable bowel syndrome, endometriosis and fibromyalgia syndrome. In this review, we highlight evidence supporting neural cross-talk in the dorsal root ganglia, spinal cord and brain levels, which might play a role in the development of chronic pain disorders through central sensitization. In addition, we focus on transient receptor potential V1 and transient receptor potential A1 as the receptor targets for chronic pain conditions, because transient receptor potential V1 and transient receptor potential A1 act as a nocisensor to mediate not only an afferent signal to the dorsal horn of the spinal cord, but also an efferent signal in the periphery through secretion of inflammatory agents, such as substance P and calcitonin gene-related peptide in nociceptive sensory neurons. Furthermore, peripheral inflammation produces multiple inflammatory mediators that act on their cognate receptors to activate intracellular signal transduction pathways and thereby modify the expression and function of transient receptor potential V1 and transient receptor potential A1 (peripheral sensitization). During tissue damage and inflammation, oxidative stress, such as reactive oxygen species or reactive carbonyl species is also generated endogenously. The highly diffusible nature might account for the actions of free radical formation far from the site of injury, thereby producing systemic pain conditions without central sensitization through neural cross-talk. Because oxidative stress is considered to induce activation of transient receptor potential A1, we also discuss exogenous and endogenous oxidative stress to elucidate its role in the pathogenesis of interstitial cystitis/bladder pain syndrome and other chronic pain conditions.

The impact of hypertriglyceridemia on prostate cancer development in patients aged ≥60 years.

OBJECTIVE: • To investigate the relationship between serum triglyceride (TG) levels and the incidence and characteristics of prostate cancer detected on biopsy. PATIENTS AND METHODS: • We evaluated data from consecutive patients who underwent prostatic biopsy. Data analysed included age, total serum prostate-specific antigen (PSA) level, prostatic volume, body mass index (BMI), TG levels, and cholesterol-lowering medications. RESULTS: • We analysed data from 905 patients, including 528 (58.3%) with positive biopsy findings. • Using 150 mg/dL as the threshold point of TG levels, multivariate analysis yielded an adjusted odds ratio (OR) reflecting the association of higher TG levels with prostate cancer diagnosis of 1.66 (95% confidence interval (CI) 1.21-2.29, P = 0.002). • Pearson correlation coefficient analysis including age, PSA level, prostatic volume, BMI and TG, showed TG level significantly correlated with BMI (r = 0.185, P < 0.001). • In the analysis by age intervals (≤59, 60-69, and ≥70 years), the association between high TG levels and positive biopsy findings was enhanced in the age groups 60-69 and ≥70 years (OR 2.10, 95% CI 1.31-3.37, P = 0.002 and OR 1.91, 95% CI 1.03-3.53, P = 0.039, respectively), but not in the group aged ≤59 years. • In patients aged ≥60 years, high TG levels were statistically significantly associated with a Gleason score of ≥8. CONCLUSIONS: • High TG levels correlated well with a higher incidence of prostate cancer, especially in patients aged ≥60 years. • High TG levels were also associated with a Gleason score of ≥8 in this age group. • Our results suggest that elderly patients with high TG levels may be more vulnerable to the development of prostate cancer with an aggressive biology.

The counterregulating role of ACE2 and ACE2-mediated angiotensin 1-7 signaling against angiotensin II stimulation in vascular cells.

To clarify the role of endogenous angiotensin (Ang)-converting enzyme 2 (ACE2) and its cleavage product, Ang 1-7, in the atherogenic stimulation of vascular cells, we investigated the effect of pharmacological inhibition of ACE2 and Mas, an Ang 1-7 receptor, on cellular responses against Ang II stimulation. We measured extracellular signal-regulated kinase (ERK) 1/2 phosphorylation by western blot, smooth muscle cell (SMC) proliferation by WST assay and the adhesion of monocytes labeled with PKH67 to endothelial cells (ECs) by fluorescence microplate reader. Cells were pretreated with Ang 1-7, olmesartan (Ang II type 1 receptor (AT1) blocker), DX600 (ACE2 inhibitor), -Ala7-Ang1-7 (D-Ala; Mas antagonist), or combinations of treatments before the application of Ang II. Treatment with Ang II increased phosphorylated ERK 1/2 of SMC and EC, proliferation of SMC and adhesion of monocyte to EC, which were blocked by olmesartan. Pretreatment with DX600 either did not accelerate or only slightly accelerated these cellular responses. However, when Ang II signaling through AT1 was reduced by olmesartan, the additional treatment with DX600 significantly blunted some of the effect of olmesartan. Similarly, pretreatment with D-Ala reduced the inhibitory effect of olmesartan in response to Ang II stimulation. Endogenous ACE2 in vascular cells may contribute to counteracting the Ang II-mediated cellular response partly by upregulating the Ang 1-7 signaling through Mas.

Patterns of failure and influence of potential prognostic factors after surgery in transitional cell carcinoma of the upper urinary tract.

BACKGROUND: We investigated the long-term outcome of upper urinary tract transitional cell carcinoma (TCC) after surgery. METHODS: The study population comprised 114 surgically treated patients with upper urinary tract TCC treated at Jikei University Hospital between March 1990 and December 2004. All these patients underwent radical surgery without any type of neoadjuvant therapy. Patterns of failure and patient survival were compared with clinicopathological parameters. RESULTS: The 5- and 10-year overall survival (OAS) rates for the patients were 85% (95% confidence interval [CI], 81%-89%) and 76% (95% CI, 69%-83%). To date, 19 patients (16.7%) have experienced distant or lymph node metastasis at a mean of 13.3 months following surgery (range, 1 to 50 months). The site of the primary tumor did not affect patient survival (P > 0.05). Both lymphovascular involvement (LVI) and positive lymph nodes were found to have poor prognosis in univariate analysis (P = 0.004 and P < 0.0001). Multivariate analysis indicated pathological stage and bladder recurrence (bladder recurrence being a better prognostic factor) to be independent predictors of metastasis-free survival, but not of OAS or cause-specific survival (CSS). CONCLUSION: Pathological stage and bladder recurrence were found to be the predictors of metastasis-free survival in this study. Further searching for reliable biomarkers is needed to accurately predict the prognosis of this malignancy.

Staphylococcal nuclease domain-containing protein 1 as a potential tissue marker for prostate cancer.

Using high molecular-weight proteomic analysis, we previously showed that Staphylococcal nuclease domain-containing protein 1 (SND1) is highly expressed in recurrent androgen-insensitive prostate cancer tissues. SND1 is a component of the RNA-induced splicing complex that mediates RNA interference, leading to degradation of specific mRNAs. The objective of this study was to further characterize SND1 expression and to investigate its biological potential in prostate cancer. Radical prostatectomy specimens were obtained from 62 prostate cancer patients. SND1 immunohistochemical staining patterns were evaluated using an in-house polyclonal antibody. We confirmed SND1 mRNA expression in prostate cancer cells using an in situ hybridization technique. To determine the importance of SND1 mRNA, we knocked down SND1 in vitro with small interfering RNA and observed a significant decrease in cell growth. SND1 was expressed in 60 of 62 prostate cancers (97%), appearing in the cytoplasm as small, granular structures; it was also present at high levels in prostate cancer specimens, while in hyperplasia specimens and normal epithelium, it was weakly or negatively expressed. SND1 expression intensity increased with increasing grade and aggressiveness of the cancer. As SND1 mRNA was overexpressed in cancer cells, the growth of these cells was suppressed following SND1 knockdown in vitro, thus representing a promising prostate cancer biomarker and therapeutic target.

Macrophage inflammatory protein-1beta induced cell adhesion with increased intracellular reactive oxygen species.

UNLABELLED: To investigate the role of macrophage inflammatory protein-1 beta (MIP-1beta) in the development of atherosclerosis, we designed an in vitro study to elucidate the mechanisms of monocyte-endothelium adhesion via intracellular reactive oxygen species (ROS). Angiotensin II (AngII) was used as a positive control. Furthermore, we examined the efficacy of MIP-1beta as a predictor of stroke and cardiovascular events in hypertensive patients. MIP-1beta or AngII stimulation significantly increased ROS production and adhesion of THP-1 cells to inflamed human umbilical vein endothelial cells. Cell adhesion and ROS production were inhibited in stimulated THP-1 cells by: inhibition of ROS signaling with N-acetylcysteine, diphenyleneiodonium, or PEG-Catalase; inhibition of PI3Kgamma with siRNA or LY294002; and by Rac1 siRNA. The MIP-1 beta or AngII stimulation did not increase surface expression of integrins, very late antigen 4 (VLA-4) and lymphocyte function-associated antigen 1 (LFA-1), but cell adhesion was reduced by using an antiVLA-4 or an antiLFA-1 antibody. Moreover, cell adhesion and ROS production stimulated with MIP-1beta or AngII were completely inhibited by fluvastatin. In our clinical study, patients with the highest quartile of MIP-1beta showed a higher risk of stroke and cardiovascular events by a Cox proportional-hazards model. In conclusion, MIP-1beta directly induced cell adhesion to endothelial cells through oxidative stress via PI3k-Rac1 cascades. Serum MIP-1beta level might be a useful predictor for cerebro-cardiovascular events in hypertensive patients. CONDENSED ABSTRACT: We designed an in vitro investigation to examine the role of MIP-1beta on the development of atherosclerosis, including cell adhesion involving CAMs and ROS production, compared with angiotensin II. Furthermore, we investigated the prognostic impact of MIP-1beta on stroke and cardiovascular events in hypertensive patients in a small cohort study.

Chemosensitization of gemcitabine-resistant human bladder cancer cell line both in vitro and in vivo using antisense oligonucleotide targeting the anti-apoptotic gene, clusterin.

OBJECTIVE: To characterize changes in clusterin (sCLU-2) expression in bladder cancer cells after continuous treatment with gemcitabine and to determine whether knockdown of sCLU-2 can re-introduce sensitivity of gemcitabine-resistant cells to treatment with gemcitabine. MATERIALS AND METHODS: A human bladder cancer cell line, UM-UC-3, was continuously exposed to increasing doses of gemcitabine in vitro, and a gemcitabine-resistant cell line UM-UC-3R was developed. The role of sCLU-2 in chemoresistant phenotype acquired in both in vitro and in vivo was then analysed using antisense oligonucleotide targeting the sCLU-2 gene (OGX-011). RESULTS: Treatment of parental UM-UC-3 cells (UM-UC-3P) with gemcitabine induced transient up-regulation of sCLU-2 protein. There was a sustained increase in sCLU-2 expression levels in UM-UC-3R compared with UM-UC-3P cells (6.4-fold). Treatment of UM-UC-3R cells with OGX-011 resulted in a dose-dependent and sequence- specific inhibition in sCLU-2 expression. Furthermore, OGX-011 chemo-sensitized UM-UC-3R cells to gemcitabine in vitro with a reduction in the concentration that reduces the effect by 50% (IC50) from 100 nm to 10 nm. Tumour volume and the incidence of metastasis in nude mice injected with UM-UC-3R cells was significantly greater than those of nude mice injected with UM-UC-3P cells; however, systemic administration of OGX-011 plus a low dose of gemcitabine significantly suppressed tumour volume and the incidence of metastasis in both groups. CONCLUSION: These findings suggest that sCLU-2 plays a significant role in the acquisition of chemoresistant phenotype in bladder cancer cells and the knockdown of sCLU-2 using OGX-011 combined with a chemotherapeutic agent could be an attractive approach for advanced bladder cancer through the enhancement of chemosensitivity.

GLI2 knockdown using an antisense oligonucleotide induces apoptosis and chemosensitizes cells to paclitaxel in androgen-independent prostate cancer.

PURPOSE: GLI transcription factors mediate hedgehog signaling and have been implicated in several human malignancies, including prostate cancer. The objectives of this study were to characterize GLI2 expression levels in human prostate cancer cell lines and tissues to test the effect of antisense oligonucleotide (ASO) targeting GLI2 on androgen-independent (AI) prostate cancer cell lines. EXPERIMENTAL DESIGN: A tissue microarray was used to characterize differences in GLI2 expression in benign prostate hyperplasia, prostate cancer treated by neoadjuvant hormonal therapy and AI prostate cancer. The effects of GLI2 ASO on PC-3 cell growth and paclitaxel chemosensitivity were assessed in vitro and in vivo. Oligonucleotide spotted microarray analysis was used to determine alteration in GLI2 coregulated genes after ASO treatment. RESULTS: The expression of GLI2 was significantly higher in prostate cancer than in benign prostate hyperplasia, decreased after androgen ablation in a time-dependent fashion, but became highly expressed again in AI prostate cancer. GLI2 ASO treatment of PC-3 cells reduced GLI2 mRNA and protein levels in a dose-dependent manner. GLI2 knockdown increased PC-3 cell apoptotic rates and significantly decreased cell growth and modulated levels of apoptosis-related genes, such as Bcl2, Bcl-xL, and clusterin. GLI2 knockdown also changed levels of several cell cycle regulators, such as cyclin D1, p27, and PKC-eta. Systematic administration of GLI2 ASO in athymic mice significantly delayed PC-3 tumor progression and enhanced paclitaxel chemosensitivity. CONCLUSIONS: These findings suggest that increased levels of GLI2 correlates with AI progression and that GLI2 may be a therapeutic target in castrate-resistant prostate cancer.

Effects of Eg5 knockdown on human prostate cancer xenograft growth and chemosensitivity.

OBJECTIVES: Microtubular inhibitors, including docetaxel, are active cytotoxics in many cancers, including prostate cancer (CaP). The Eg5 gene, a member of the kinesin-5 family, plays critical roles in proper mitotic spindle function, and is a potential microtubule-related target for proliferating cancer cells. To investigate the functional activities of Eg5 in CaP, we used an antisense oligonucleotide (ASO) targeting Eg5 to assess the potency and anti-cancer activity of Eg5 ASO treatment for androgen-independent CaP cells in vitro and in vivo. RESULTS: PC3 cells express higher Eg5 protein and mRNA levels compared to LNCaP cells. In both cell lines, Eg5 ASO treatment reduced mRNA and protein levels in a dose-dependent manner and a complete reduction of Eg5 protein levels was observed at 100 nM. Dose-dependent inhibition in cell growth, potent G2/M phase arrest, and increases in apoptotic sub-G1 fraction were also observed using Eg5 ASO. Surprisingly, low dose Eg5 ASO significantly antagonized cytotoxic effects of paclitaxel. In vivo, Eg5 ASO monotherapy significantly reduced both LNCaP and PC-3 tumor growth but combination treatment with paclitaxel did not yield additive benefits. CONCLUSIONS: These findings suggest that while Eg5 is a potential target to delay androgen-independent CaP growth, combination treatment with paclitaxel may not be desirable.