Tumor-associated macrophages (TAMs) are the most abundant inflammatory infiltrates in the tumor microenvironment and contribute to lymph node (LN) metastasis. However, the precise mechanisms of TAMs-induced LN metastasis remain largely unknown. Herein, we identify a long noncoding RNA, termed Lymph Node Metastasis Associated Transcript 1 (LNMAT1), which is upregulated in LN-positive bladder cancer and associated with LN metastasis and prognosis. Through gain and loss of function approaches, we find that LNMAT1 promotes bladder cancer-associated lymphangiogenesis and lymphatic metastasis. Mechanistically, LNMAT1 epigenetically activates CCL2 expression by recruiting hnRNPL to CCL2 promoter, which leads to increased H3K4 tri-methylation that ensures hnRNPL binding and enhances transcription. Furthermore, LNMAT1-induced upregulation of CCL2 recruits macrophages into the tumor, which promotes lymphatic metastasis via VEGF-C excretion. These findings provide a plausible mechanism for LNMAT1-modulated tumor microenvironment in lymphatic metastasis and suggest that LNMAT1 may represent a potential therapeutic target for clinical intervention in LN-metastatic bladder cancer.

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Wet filter paper is central to a powerful new method of mass spectrometry presented by G. Cooks, Z. Ouyang et al. in their Communication on p. 877 ff. Samples can be preloaded onto the paper, added from solution, or transferred from surfaces using the paper as a wipe. Potential applications lie in quantitative analysis of whole blood from finger pricks or in surface wipe-and-analyze experiments for security applications, and in in situ analysis.

Paper spray mass spectrometry (PS-MS) is explored as a fast and convenient way for direct analysis of molecules in tissues with minimum sample pretreatment. This technique allows direct detection of different types of molecules such as hormones, lipids and therapeutic drugs in short total analysis times (less than one minute) using a small volume of tissue sample (typically 1 mm 3 or less). The tissue sample could be obtained by needle aspiration biopsy, by punch biopsy, or by rubbing a thin tissue section across the paper. There exists potential for the application of paper spray mass spectrometry together with tissue biopsy for clinical diagnostics.

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Purpose: Chemoresistance and tumor relapse are the leading cause of deaths in bladder cancer patients. Bladder cancer stem cells (BCSCs) have been reported to contribute to these pathologic properties. However, the molecular mechanisms underlying their self-renewal and chemoresistance remain largely unknown. In the current study, a novel lncRNA termed Low expressed in Bladder Cancer Stem cells (lnc-LBCS) has been identified and explored in BCSCs.Experimental Design: Firstly, we establish BCSCs model and explore the BCSCs-associated lncRNAs by transcriptome microarray. The expression and clinical features of lnc-LBCS are analyzed in three independent large-scale cohorts. The functional role and mechanism of lnc-LBCS are further investigated by gain-and loss-of-function assays in vitro and in vivo.Results: Lnc-LBCS is significantly downregulated in BCSCs and cancer tissues, and correlates with tumor grade, chemo-therapy response, and prognosis. Moreover, lnc-LBCS markedly inhibits self-renewal, chemoresistance, and tumor initiation of BCSCs both in vitro and in vivo. Mechanistically, lnc-LBCS directly binds to heterogeneous nuclear ribonucleoprotein K (hnRNPK) and enhancer of zeste homolog 2 (EZH2), and serves as a scaffold to induce the formation of this complex to repress SRY-box 2 (SOX2) transcription via mediating histone H3 lysine 27 tri-methylation. SOX2 is essential for self-renewal and chemoresistance of BCSCs, and correlates with the clinical severity and prognosis of bladder cancer patients.Conclusions: As a novel regulator, lnc-LBCS plays an important tumor-suppressor role in BCSCs' self-renewal and chemoresistance, contributing to weak tumorigenesis and enhanced chemosensitivity. The lnc-LBCS-hnRNPK-EZH2-SOX2 regulatory axis may represent a therapeutic target for clinical intervention in chemoresistant bladder cancer.

Our findings suggest that CD8(+) T cells might have a significant role in tumor immunity by expressing CD103 in intratumor regions of bladder urothelial cell carcinoma tissues. Intratumor CD103(+) TILs could potentially serve as a prognostic marker in patients with bladder urothelial cell carcinoma.

WD repeat domain 5 (WDR5) plays an important role in various biological functions through the epigenetic regulation of gene transcription; however, its role in bladder cancer remains largely unknown. Our study investigated the role of WDR5 in bladder cancer and demonstrated that WDR5 was upregulated in bladder cancer tissues, and elevated WDR5 protein levels positively correlated with advanced tumor stage and poor survival. Through gain or loss of function, we demonstrated that WDR5 promoted proliferation, self-renewal and chemoresistance to cisplatin in bladder cancer cells in vitro, and tumor growth in vivo. Mechanistically, WDR5 regulated various functions in bladder cancer by mediating the transcription of cyclin B1, cyclin E1, cyclin E2, UHMK1, MCL1, BIRC3 and Nanog by histone H3 lysine 4 trimethylation. Therefore, we have discovered that WDR5 plays an important role in bladder cancer suggesting that WDR5 is a potential biomarker and a promising target in the treatment of bladder cancer.