Tumor-associated macrophages (TAMs) and cancer-associated fibroblasts (CAFs) are reported to be associated with poor prognosis, depending on their pro-tumoral roles. Current knowledge of TAMs and CAFs in the tumor microenvironment of urothelial cancer of the bladder (UCB) is limited. Therefore, we investigated the paracrine effect induced by TAMs and CAFs in the tumor microenvironment of human UCB. For this, we first carried out immunohistochemical analysis for CXCL1, CD204 (TAM marker), αSMA (CAF marker), E-cadherin, and MMP2 using 155 UBC tissue samples. Next, CXCL1-overexpressing clones of THP-1-derived TAMs and NIH3T3-derived CAFs were developed by lentiviral vector infection. The immunohistochemical study showed high CXCL1 levels in UCB cells to be associated with enhanced recruitment of TAMs/CAFs, higher metastatic potential, and poor prognosis. Three-dimensional (3D) co-culture of UCB cells and TAMs/CAFs suggested that CXCL1 production in TAMs/CAFs play an important role in cell-to-cell adhesion and interaction among cancer cells and these stromal cells. CXCL1-expressing TAMs/CAFs enhanced tumor growth of subcutaneous UCB tumors in nude mice when injected together. In addition, an experiment using the orthotopic bladder cancer model revealed that CXCL1 production in TAMs/CAFs supported tumor implantation into the murine bladder wall and UCB growth when injected together, which was confirmed by clinical data of patients with bladder cancer. Thus, CXCL1 signaling in the tumor microenvironment is highly responsible for repeated intravesical recurrence, disease progression, and drug resistance through enhanced invasion ability. In conclusion, disrupting CXCL1 signaling to dysregulate this chemokine is a promising therapeutic approach for human UCB.

We recently identified a novel human AlkB homologue, ALKBH8, which is expressed in various types of human cancers including human urothelial carcinomas. In examining the role and function of ALKBH8 in human bladder cancer development in vitro, we found that silencing of ALKBH8 through small interfering RNA transfection reduced reactive oxygen species (ROS) production via down-regulation of NAD(P)H oxidase-1 (NOX-1) and induced apoptosis through subsequent activation of c-jun NH 2 -terminal kinase (JNK) and p38. However, we also found that JNK and p38 activation resulted in phosphorylation of H2AX (;H2AX), a variant of mammalian histone H2A, which contributes to the apoptosis induced by silencing ALKBH8 and NOX-1. Silencing of ALKBH8 significantly suppressed invasion, angiogenesis, and growth of bladder cancers in vivo as assessed both in the chorioallantoic membrane assay and in an orthotopic mouse model using green fluorescent protein-labeled KU7 human urothelial carcinoma cells. Immunohistochemical examination showed high expression of ALKBH8 and NOX-1 proteins in high-grade, superficially and deeply invasive carcinomas (pT 1 and >pT 2 ) as well as in carcinoma in situ, but not in low-grade and noninvasive phenotypes (pT a ). These findings indicate an essential role for ALKBH8 in urothelial carcinoma cell survival mediated by NOX-1-dependent ROS signals, further suggesting new therapeutic strategies in human bladder cancer by inducing JNK/p38/;H2AX-mediated cell death by silencing of ALKBH8. [Cancer Res 2009;69(7):3157-64]

Background-: Data exist that demonstrate isoflavones' potent antiproliferative effects on prostate cancer cells. We evaluated the efficacy of isoflavone in patients with PSA recurrent prostate cancer after prior therapy. We postulated that isoflavone therapy would slow the rate of rise of serum PSA.

The clinical significance of regulatory T cells (Treg) and tumor-associated macrophages (TAM) in the tumor microenvironment of human bladder cancer remains unclear. The aim of this study is to explore their relevance to oncological features in non-muscle invasive bladder cancer (NMIBC). We carried out immunohistochemical analysis of forkhead box P3 (FOXP3, Treg maker), CD204 (TAM marker), and interleukin-6 (IL6) using surgical specimens obtained from 154 NMIBC patients. The Treg and TAM counts surrounding the cancer lesion and IL6-positive cancer cell counts were evaluated against clinicopathological variables. We focused on the ability of the Treg and TAM counts around the cancer lesion to predict outcomes after adjuvant intravesical Bacille Calmette–Guérin (BCG) treatment. High Treg counts were associated with female patients, older age, T1 category, and high tumor grade. TAM count was significantly correlated with Treg count and with IL6-positive cancer cell count. In our analysis of 71 patients treated with BCG, high counts of Treg and TAM were associated with shorter recurrence-free survival, and the former was an independent predictor of recurrence. Poor response to intravesical BCG was associated with Treg and TAM in the tumor microenvironment. Disrupting the immune network can be a supplementary therapeutic approach for NMIBC patients receiving intravesical BCG.