CCL2 induces resistance to the antiproliferative effect of cabazitaxel in prostate cancer cells.

Understanding the mechanism of chemoresistance and disease progression in patients with prostate cancer is important for developing novel treatment strategies. In particular, developing resistance to cabazitaxel is a major challenge in patients with docetaxel-resistant and castration-resistant prostate cancer (CRPC) because cabazitaxel is often administered as a last resort. However, the mechanism by which cabazitaxel resistance develops is still unclear. C-C motif chemokine ligands (CCL) were shown to contribute to the castration resistance of prostate cancer cells via an autocrine mechanism. Therefore, we focused on CCL as key factors of chemoresistance in prostate cancer cells. We previously established a cabazitaxel-resistant cell line, DU145-TxR/CxR, from a previously established paclitaxel-resistant cell line, DU145-TxR. cDNA microarray analysis revealed that the expression of CCL2 was upregulated in both DU145-TxR and DU145-TxR/CxR cells compared with DU145 cells. The secreted CCL2 protein level in DU145-TxR and DU145-TxR/CxR cells was also higher than in parental DU145 cells. The stimulation of DU145 cells with CCL2 increased the proliferation rate under treatments with cabazitaxel, and a CCR2 (a specific receptor of CCL2) antagonist suppressed the proliferation of DU145-TxR and DU145-TxR/CxR cells under treatments of cabazitaxel. The CCL2-CCR2 axis decreased apoptosis through the inhibition of caspase-3 and poly(ADP-ribose) polymerase (PARP). CCL2 is apparently a key contributor to cabazitaxel resistance in prostate cancer cells. Inhibition of the CCL2-CCR2 axis may be a potential therapeutic strategy against chemoresistant CRPC in combination with cabazitaxel.

Tumor necrosis factor-α induces prostate cancer cell migration in lymphatic metastasis through CCR7 upregulation.

Understanding the mechanism of lymph node metastasis, a poor prognostic sign for prostate cancer, and the further dissemination of the disease is important to develop novel treatment strategies. Recent studies have reported that C-C chemokine receptor 7 (CCR7), whose ligand is CCL21, is abundantly expressed in lymph node metastasis and promotes cancer progression. Tumor necrosis factor-α (TNF-α) is chronically produced at low levels within the tumor microenvironment. The aim of this study was to determine whether TNF-α promotes prostate cancer dissemination from metastatic lymph nodes through activation of the CCL21/CCR7 axis. First, human prostate cancer cells were determined to express both TNF-α and CCR7. Second, low concentrations of TNF-α were confirmed to induce CCR7 in prostate cancer cells through phosphorylation of ERK. Finally, CCL21 was found to promote the migration of prostate cancer cells through phosphorylation of the protein kinase p38. Our results suggest that TNF-α leads to the induction of CCR7 expression and that the CCL21/CCR7 axis might increase the metastatic potential of prostate cancer cells in lymph node metastasis.

C-C motif ligand 5 promotes migration of prostate cancer cells in the prostate cancer bone metastasis microenvironment.

Chemokines and their receptors have key roles in cancer progression. The present study investigated chemokine activity in the prostate cancer bone metastasis microenvironment. Growth and migration of human prostate cancer cells were assayed in cocultures with bone stromal cells. The migration of LNCaP cells significantly increased when co-cultured with bone stromal cells isolated from prostate cancer bone metastases. Cytokine array analysis of conditioned medium from bone stromal cell cultures identified CCL5 as a concentration-dependent promoter of LNCaP cell migration. The migration of LNCaP cells was suppressed when C-C motif ligand 5 (CCL5) neutralizing antibody was added to cocultures with bone stromal cells. Knockdown of androgen receptor with small interfering RNA increased the migration of LNCaP cells compared with control cells, and CCL5 did not promote the migration of androgen receptor knockdown LNCaP. Elevated CCL5 secretion in bone stromal cells from metastatic lesions induced prostate cancer cell migration by a mechanism consistent with CCL5 activity upstream of androgen receptor signaling.

The relationship between prostate-specific antigen and TNM classification or Gleason score in prostate cancer patients with low prostate-specific antigen levels.

BACKGROUND: Prostate-specific antigen (PSA) is a useful biomarker for risk classification in patients with prostate cancer. However, it is unclear whether a correlation exists between low PSA levels (<10 ng/ml) at diagnosis and prognosis. METHODS: Of the 642 Japanese patients who underwent prostate biopsy and were diagnosed with prostate cancer at Kanazawa University Hospital from 2000 to 2010, 406 patients with a PSA level <20 ng/ml were retrospectively reviewed. RESULTS: PSA levels in 275 (68%) patients were <10 ng/ml. Although the percentage of Gleason score 8-10 in patients with a PSA level of <3.5 ng/ml was higher than that in patients with a PSA level between 3.5 and 10 ng/ml, it was not statistically significant. On the other hand, the percentage of higher stage (T3 and T4) patients with a PSA level <3.5 ng/ml was significantly greater than that in patients with a PSA level between 3.5 and 10 ng/ml (P < 0.0001). The percentage of metastases (N1 and M1) in patients with a PSA level <3.5 ng/ml was also significantly higher than that in patients with a PSA level between 3.5 and 10 ng/ml (P = 0.0112). CONCLUSIONS: Patients with prostate cancer with a PSA level <3.5 ng/ml at diagnosis had a more advanced stage of cancer compared with those with a PSA level between 3.5 and 10 ng/ml. Therefore, risk classification using PSA levels at diagnosis may need to take into consideration this specific PSA range in order to better predict survival.

Androgen deprivation triggers a cytokine signaling switch to induce immune suppression and prostate cancer recurrence.

Androgen deprivation therapy (ADT) is an effective but not curative treatment for advanced and recurrent prostate cancer (PC). We investigated the mechanisms controlling the response to androgen-deprivation by surgical castration in genetically-engineered mouse models (GEMM) of PC, using high frequency ultrasound imaging to rigorously measure tumor volume. Castration initially causes almost all tumors to shrink in volume, but many tumors subsequently recur within 5-10 weeks. Blockade of tumor necrosis factor (TNF) signaling a few days in advance of castration surgery, using a TNFR2 ligand trap, prevents regression in a PTEN-deficient GEMM. Following tumor regression, a basal stem cell-like population within the tumor increases along with TNF protein levels. Tumor cell lines in culture recapitulate these in vivo observations, suggesting that basal stem cells are the source of TNF. When TNF signaling blockade is administered immediately prior to castration, tumors regress but recurrence is prevented, implying that a late wave of TNF secretion within the tumor, which coincides with the expression of NFkB regulated genes, drives recurrence. The inhibition of signaling downstream of one NFkB-regulated protein, chemokine C-C motif ligand 2 (CCL2), prevents post-castration tumor recurrence, phenocopying post-castration (late) TNF signaling blockade. CCL2 was originally identified as a macrophage chemoattractant and indeed at late times after castration gene sets related to chemotaxis and migration are up-regulated. Importantly, enhanced CCL2 signaling during the tumor recurrence phase coincides with an increase in pro-tumorigenic macrophages and a decrease in CD8 T cells, suggesting that recurrence is driven at least in part by tumor immunosuppression. In summary, we demonstrate that a therapy-induced switch in TNF signaling, a consequence of the increased stem cell-like character of the residual tumor cells surviving ADT, induces an immunosuppressive tumor microenvironment and concomitant tumor recurrence.

Epigenetic Suppression of SERPINB1 Promotes Inflammation-Mediated Prostate Cancer Progression.

Granulocytic myeloid infiltration and resultant enhanced neutrophil elastase (NE) activity is associated with poor outcomes in numerous malignancies. We recently showed that NE expression and activity from infiltrating myeloid cells was high in human prostate cancer xenografts and mouse Pten-null prostate tumors. We further demonstrated that NE directly stimulated human prostate cancer cells to proliferate, migrate, and invade, and inhibition of NE in vivo attenuated xenograft growth. Interestingly, reduced expression of SERPINB1, an endogenous NE inhibitor, also correlates with diminished survival in some cancers. Therefore, we sought to characterize the role of SERPINB1 in prostate cancer. We find that SERPINB1 expression is reduced in human metastatic and locally advanced disease and predicts poor outcome. SERPINB1 is also reduced in Pten-null mouse prostate tumors compared with wild-type prostates, and treatment with sivelestat (SERPINB1 pharmacomimetic) attenuates tumor growth. Knockdown of highly expressed SERPINB1 in nonmalignant prostatic epithelial cells (RWPE-1) increases proliferation, decreases apoptosis, and stimulates expression of epithelial-to-mesenchymal transition markers. In contrast, stable SERPINB1 expression in normally low-expressing prostate cancer cells (C4-2) reduces xenograft growth in vivo. Finally, EZH2-mediated histone (H3K27me3) methylation and DNA methyltransferase-mediated DNA methylation suppress SERPINB1 expression in prostate cancer cells. Analysis of The Cancer Genome Atlas and pyrosequencing demonstrate hypermethylation of the SERPINB1 promoter in prostate cancer compared with normal tissue, and the extent of promoter methylation negatively correlates with SERPINB1 mRNA expression. IMPLICATIONS: Our findings suggest that the balance between SERPINB1 and NE is physiologically important within the prostate and may serve as a biomarker and therapeutic target in prostate cancer.

Tumor-associated macrophages promote prostate cancer migration through activation of the CCL22-CCR4 axis.

Previous studies have found that tumor-associated macrophages (TAMs) promote cancer progression. We previously reported that TAMs promote prostate cancer metastasis via activation of the CCL2-CCR2 axis. The CCR4 (receptor of CCL17 and CCL22) expression level in breast cancer was reported to be associated with lung metastasis. The aim of this study was to elucidate the role of CCR2 and CCR4 in prostate cancer progression. CCR2 and CCR4 were expressed in human prostate cancer cell lines and prostate cancer tissues. In vitro co-culture of prostate cancer cells and macrophages resulted in increased CCL2 and CCR2 levels in prostate cancer cells. The addition of CCL2 induced CCL22 and CCR4 production in prostate cancer cells. The migration and invasion of prostate cancer cells via enhanced phosphorylation of Akt were promoted by CCL17 and CCL22. CCR4 may be a potential candidate for molecular-targeted therapy.

Aplastic anemia associated with severe hemorrhagic cystitis following radiotherapy for prostate cancer.

Hemorrhagic cystitis is a rare complication following radiotherapy for intrapelvic cancer types, including cervical cancer, bladder cancer and prostate cancer. The severity of hemorrhagic cystitis is different in each case, although symptoms improve spontaneously in certain cases, and often significant morbidity requiring numerous interventions occurs. Since no treatment strategy exists with high evidences for such severe hemorrhagic cystitis, urologists have difficulty in solving the bleeding and pain, which the patients suffer. Aplastic anemia is a rare blood disorder, with an incidence reported as 2/1 million individuals annually. Patients have a risk of diffuse bleeding for presentation with anemia, thrombocytopenia and neutropenia. The present report presented a case of severe hemorrhagic cystitis remitted successfully by the treatment for underlying aplastic anemia.

Metastasectomy Improves Survival in Patients with Metastatic Urothelial Carcinoma.

Metastatic urothelial carcinoma is one of the most fatal urological malignancies. Cisplatin-based systemic chemotherapy is the standard treatment for metastatic urothelial carcinoma, and there is little evidence to support metastasectomy. The aims of the study were to evaluate the efficacy of metastasectomy and to investigate the prognoses of the patients. The study included 436 patients with urothelial carcinoma who were treated at our hospital. Of these, we included and retrospectively analyzed 29 patients who received curative treatment for the primary tumor and had been treated for metastases. Seven of these patients underwent metastasectomy. In a multivariate analysis, a serum C-reactive protein level before treatment for metastasis of <1 mg/dl and metastasectomy were independent significant predictors of both better progression-free survival and better overall survival. Metastasectomy may be considered a potential treatment for patients with metastases from urothelial carcinoma.

Serum chemokine (CC motif) ligand 2 level as a diagnostic, predictive, and prognostic biomarker for prostate cancer.

Prostate-specific antigen (PSA) is regarded as the most sensitive biomarker for prostate cancer. Although androgen/androgen receptor (AR) signaling promotes prostate cancer progression, suppression of AR signaling induces chemokine (CC motif) ligand 2 (CCL2), which enables prostate cancer cells to gain metastatic potential. AR-controlled PSA alone may be an unreliable biomarker for patients receiving androgen deprivation therapy. Therefore, we investigated the validity of CCL2 as a complementary biomarker to PSA for prostate cancer. Our in vitro approach of enriching for prostate cancer cells with higher migration potential showed that CCL2 activated cellular migration. Importantly, we found that CCL2 levels were significantly different between men (n = 379) with and without prostate cancer. Patients with CCL2 ≥ 320 pg/mL had worse overall survival and prostate cancer -specific survival than those with CCL2 < 320 pg/mL. A novel risk classification was developed according to the risk factors CCL2 ≥ 320 pg/mL and PSA ≥ 100 ng/mL, and scores of 2, 1, and 0 were defined as poor, intermediate, and good risk, respectively, and clearly distinguished patient outcomes. CCL2 may serve as a novel biomarker for prostate cancer. The novel risk classification based on combining CCL2 and PSA is more reliable than using either alone.

Efficacy of tegafur-uracil in advanced urothelial cancer patients after the treatment failure of platinum-based chemotherapy.

BACKGROUND: Platinum-based chemotherapy is the first-line treatment for advanced urinary tract urothelial cancers. However, the optimal second-line treatment is unclear. Although tegafur-uracil is sometimes used for advanced urothelial cancer patients after the treatment failure of platinum-based chemotherapy, there is little evidence regarding its use as a second-line treatment. PATIENTS AND METHODS: Advanced urothelial cancer patients previously treated with platinum-based chemotherapy were retrospectively analyzed. Overall survival (OS) was compared between patients with and without tegafur-uracil treatment. RESULTS: Thirty-one patients (27 and 4 patients with and without tegafur-uracil treatment, respectively) were analyzed. OS from the last day of the final chemotherapy course was better in patients with tegafur-uracil treatment than in those without (p<0.001, 358 and 66.5 days of the median survival time, respectively). CONCLUSION: Tegafur-uracil may be a candidate for the secondary treatment of advanced urothelial cancer patients after the treatment failure of platinum-based chemotherapy.

Predictive factor and antihypertensive usage of tyrosine kinase inhibitor-induced hypertension in kidney cancer patients.

Hypertension (HT) is the common adverse event associated with vascular endothelial growth factor receptor-tyrosine kinase inhibitors (VEGFR-TKI). The present study was performed to identify the predictive factors of TKI-induced HT and to determine the classes of antihypertensive agents (AHTA) that demonstrate optimal efficacy against this type of HT. The charts of 50 cases of patients that had received VEGFR-TKI treatment were retrospectively examined. The association between patient background and TKI-induced HT, and the effect of administering AHTA were analyzed. High systolic blood pressure at baseline was identified to be a predictive factor for HT. In addition, there was no difference observed between calcium channel blockers (CCBs) and angiotensin receptor II blockers (ARBs) as first-line AHTA for the control of HT. The findings of the present study may aid with predicting the onset of TKI-induced HT, as well as for its management via the primary use of either CCBs or ARBs.

Outcomes and predictive factors of prostate cancer patients with extremely high prostate-specific antigen level.

PURPOSE: Prostate-specific antigen (PSA) is a useful biomarker of prostate cancer (PCa). High-risk localized PCa is defined using T stage, Gleason score (GS), and PSA. However, PSA level defining high-risk PCa is at most 20 ng/mL. In PCa patients with high PSA, it is unclear whether PSA itself can be a prognostic factor. METHODS: Of 642 patients who were diagnosed as PCa, 90 patients with PSA > 100 ng/mL were retrospectively analyzed. Patients were divided into three groups according to PSA level: very high (>1,000 ng/mL), moderately high (200-1,000 ng/mL), and slightly high (100-200 ng/mL). RESULTS: There were no significant differences in overall survival or PCa-specific survival (PCaSS) among the three groups. Regardless of PSA level, high M stage and GS significantly reduced PCaSS. When the risk classification was made using M stage and GS (high risk = M1 and GS ≥ 9, low risk = M0 and GS < 9, and intermediate risk = others), PCaSS was significantly different among high-, intermediate-, and low-risk groups with 5-year survival rates of 58.2, 80.6, and 100 %, respectively. Although there were no differences in treatment performed during the castration-resistant stage, patients undergoing alternative anti-androgen and zoledronic acid treatment had better PCaSS after being castration-resistant. CONCLUSIONS: As PSA could not be a prognostic factor in PCa patients with high PSA > 100 ng/mL, the novel risk classification using M stage and GS may help clinicians to predict PCaSS and to plan follow-up schedules after diagnosis.

Factors predictive of oncological outcome after nephroureterectomy: comparison between laparoscopic and open procedures.

BACKGROUND: Although laparoscopic radical nephroureterectomy is the standard treatment for localized upper urinary tract urothelial carcinoma, open radical nephroureterectomy has been reported to have a different rate of intravesical recurrence. PATIENTS AND METHODS: Intravesical recurrence-free, progression-free, and overall survival rates among patients undergoing open and laparoscopic radical nephroureterectomy from 2002 to 2013 were analyzed. RESULTS: Although no single factor predicted intravesical recurrence-free survival, a past history of bladder cancer or grade 3 was related to poorer intravesical recurrence-free survival rate in patients treated with laparoscopic radical nephroureterectomy. Moreover, the novel proposed risk classification based on our data clearly showed better progression-free survival and overall survival, as well as intravesical recurrence-free survival, in patients treated with laparoscopic radical nephroureterectomy. CONCLUSION: The findings reported here may help urologists predict oncological outcomes and to plan follow-up schedules after laparoscopic radical nephroureterectomy.