Chengyong Lei

The YAP1 oncogene contributes to bladder cancer cell proliferation and migration by regulating the H19 long noncoding RNA

BACKGROUND Yes-associated protein 1 (YAP1) and long noncoding RNA H19 act as potent oncogenes in many human cancers, but little is known about their roles in bladder cancer or their relationship with each other. METHODS Quantitative real-time polymerase chain reaction and western blotting were performed retrospectively on human bladder cancer specimens and on bladder cancer cell lines (UMUC-3, EJ, and 5637). YAP1 and H19 expression levels were detected and correlated with clinical and pathologic grades. To determine whether YAP1 regulates H19 expression, their genes were overexpressed or suppressed in 5637 and UMUC-3 cells. The effects of YAP1/H19 on proliferation and migration were determined by viability, colony formation, transwell migration, and wound-healing assays. RESULTS YAP1 and H19 expression levels were markedly elevated in bladder cancer tissues and cells, and H19 expression was found to be significantly associated with YAP1 expression. Determination of their clinicopathologic significance in 40 human bladder cancer tissues showed that specimens in which YAP1 and H19 were overexpressed were associated with poorer clinicopathologic prognosis. In addition, YAP1 was found to enhance H19 expression, whereas H19 had no significant effect on YAP1 expression in bladder cancer cells. Furthermore, the results of in vitro analyses suggested that this association regulates cell proliferation and migration. CONCLUSION Our results emphasize the importance of YAP1 and H19 in bladder cancer progression and indicate that H19, at least in part, is induced by YAP1 overexpression.

The granulocyte macrophage-colony stimulating factor surface modified MB49 bladder cancer stem cells vaccine against metastatic bladder cancer.

The MB49 bladder cancer cell vaccine was effective against bladder cancer in the mice model in previous studies. However, part of the tumors regrew as the vaccine could not eliminate the cancer stem cells (CSCs). MB49 bladder cancer stem cells (MCSCs) were isolated by a combination of the limited dilution method and the serum free culture medium method. MCSCs possessed higher expression of CD133, CD44, OCT4, NANOG, and ABCG2, the ability of differentiation, higher proliferative abilities, lower susceptibility to chemotherapy, greater migration in vitro, and stronger tumorigenic abilities in vivo. Then streptavidin-mouse granulocyte macrophage-colony stimulating factor (SA-mGM-CSF) MCSCs vaccine was prepared. SA-mGM-CSF MCSCs vaccine extended the survival of the mice and inhibited the growth of tumor in protective, therapeutic, memorial and specific immune response experiments. The level of immunoglobulin G and the ratio of dendritic cells and CD4(+) and CD8(+) T cells were highest in the experimental group when compared to those in other four control groups, as well as for the cytotoxicity assay. We demonstrated that SA-mGM-CSF MCSCs vaccine induces an antitumor immune response to metastatic bladder cancer.

Development of a therapy against metastatic bladder cancer using an interleukin-2 surface-modified MB49 bladder cancer stem cells vaccine

IntroductionIn previous study the streptavidin interleukin-2 (SA-IL-2)-modified MB49 vaccine was effective against bladder cancer in a mouse model. However, a small portion of tumors regrew because the vaccine could not eliminate MB49 bladder cancer stem cells (MCSCs). Accordingly, we developed a SA-IL-2-modified MCSCs vaccine and evaluated its antitumor effects.MethodsMCSCs were isolated and identified in cancer stem cells (CSCs) characters, with high expression of CSCs markers, higher resistance to chemotherapy, greater migration in vitro, and stronger tumorigenicity in vivo. The SA-IL-2 MCSCs vaccine was prepared and its bioactivity was evaluated. The protective, therapeutic, specific and memory immune response in animal experiments were designed to identify whether the vaccine elicited antitumor immunity and acted against metastatic bladder cancer.ResultsMCSCs had higher level of CD133 and CD44, less susceptibility to chemotherapy, more pronounced migration and greater tumorigenic ability. The successfully prepared SA-IL-2 MCSCs vaccine inhibited the tumor volume and prolonged mice survival in animal experiments. The expression of IgG, the population of dendritic cells, CD8+ and CD4+ T cells were highest in the experimental group than in the four control groups.ConclusionsThe SA-IL-2 MCSCs vaccine induced an antitumor immune response and was used to eliminate MCSCs to prevent tumor regrowth.

Giant Retrovesical Ectopic Prostate Tissue: A Case Report and Review of theLiterature

We report an unusual case of retrovesical ectopic prostate tissue in a 71-year-old man, whose prostate-specific antigen was 10.20 ng/ml. Transabdominal ultrasonography, pelvic computed tomography showed a heterogeneous, solid-cystic, 8 cm × 8.8 cm × 8.5 cm mass in contact with the posterior wall of the bladder. The patient underwent a laparoscopic pelvic neoplasm resection. Pathological examination confirmed the retrovesical tumor was normal prostate tissue.

A modified method by differential adhesion and serum-free culture medium for enrichment of cancer stem cells

Objective: In this study, we showed a modified method for the isolation of cancer stem cells (CSCs) using a combination of differential adhesion method and serum-free culture medium (SFM) method. Materials and Methods: Trypsin-sensitive cells and trypsin-resistant cells were isolated from MB49, EJ, and SK-OV-3 cells using a combination of differential adhesion method and SFM method. The CSCs markers expression of trypsin-resistant cells was verified by the flow cytometry, the Western blotting, and the quantitative polymerase chain reaction. Functional comparisons were verified by the resistance to chemotherapy assay, the transwell assay, and the tumor xenograft formation assay. Results: Trypsin-resistant cells were isolated successfully. They were identified with high expression of CSCs markers and possessed higher resistance to chemotherapy, greater migration in vitro and stronger tumorigenic abilities in vivo. Conclusion: Trypsin-resistant cells showed specific CSCs characterizations. They were able to be isolated successfully with a modified method by a combination of differential adhesion method and SFM method.