Role of external radiation therapy in urinary cancers

Hypomethylation of PlncRNA-1 promoter enhances bladder cancer progression through the miR-136-5p/Smad3 axis

Apart from being potential prognostic biomarkers and therapeutic targets, long non-coding RNAs (lncRNAs) modulate the development and progression of multiple cancers. PlncRNA-1 is a newly discovered lncRNA that exhibits the above properties through multiple regulatory pathways. However, the clinical significance and molecular mechanisms of PlncRNA-1 in bladder cancer have not been established. PlncRNA-1 was found to be overexpressed in 71.43% of bladder cancer tissues. Moreover, the expression level correlated with tumor invasion, T stage, age, and number of tumors, but not with gender, recurrent status, preoperative treatment, pathological grade, and tumor size. The expression level of PlncRNA-1 can, to a certain extent, be used as a predictor of the degree of tumor invasion and T stage among BC patients. Inhibiting PlncRNA-1 expression impaired the proliferation, migration, and invasion of T24 and 5637 bladder cancer cells in vitro and in vivo. Specifically, PlncRNA-1 promoter in BC tissues was found to be hypomethylated at position 131 (36157603 on chromosome 21). PlncRNA-1 promoter hypomethylation induces the overexpression of PlncRNA-1. In addition, PlncRNA-1 modulated the expression of smad3 and has-miR-136-5p (miR-136). Conversely, miR-136 regulated the expression of PlncRNA-1 and smad3. PlncRNA-1 mimics competitive endogenous RNA (ceRNA) in its regulation of smad3 expression by binding miR-136. Rescue analysis further revealed that modulation of miR-136 could reverse the expression of smad3 and epithelial–mesenchymal transition (EMT) marker proteins impaired by PlncRNA-1. In summary, PlncRNA-1 has important clinical predictive values and is involved in the post-transcriptional regulation of smad3. The PlncRNA-1/miR-136/smad3 axis provides insights into the regulatory mechanism of BC, thus may serve as a potential therapeutic target and prognostic biomarker for cancer.

Long non-coding RNA CASC9 promotes tumor growth and metastasis via modulating FZD6/Wnt/β-catenin signaling pathway in bladder cancer

BACKGROUND

Accumulating evidence have highlighted the importance of long noncoding RNAs (lncRNAs) in multiple cancers development and progression. Cancer susceptibility candidate 9 (CASC9) is a novel long non-coding RNA and plays important regulatory role in diverse biological processes of cancers. However, the clinical significance and molecular mechanism of CASC9 in bladder cancer is still unknown.

METHODS

Comprehensive lncRNAs profiling analysis were conducted to identify lncRNAs profile alterations and uncover valuable lncRNA candidates for bladder cancer. The expression level of CASC9 was determined in a total of 106 patients with bladder cancer. Loss-of-function experiments were performed to identify the functions of CASC9 in tumor growth and metastasis of bladder cancer in vitro and in vivo. Bioinformatics analysis and further experiments were performed to explore the molecular mechanisms underlying the functions of CASC9.

RESULTS

This study found that CASC9 expression was markedly upregulated in bladder cancer and related to histological grade, TNM stage and prognosis. Knockdown of CASC9 inhibited tumor growth and metastasis of bladder cancer in vitro and in vivo. Mechanistically, we found that CASC9 functions as a miRNA sponge to positively regulate FZD6 expression and subsequently activates Wnt/β-catenin signaling pathway, thus playing an oncogenic role in bladder cancer pathogenesis.

CONCLUSION

In summary, lncRNA CASC9 plays a critical regulatory role in bladder cancer. The CASC9/miR-497-5p/ FZD6 axis provides insights for regulatory mechanism of bladder cancer, and new strategies for clinical practice.

Quantitative risk stratification and individual comprehensive therapy for invasive bladder cancers in China

BACKGROUND

To evaluate the risk factors for invasive bladder cancer and to develop a predictive model for the improvement of individual comprehensive therapy for invasive bladder cancers.

MATERIALS AND METHODS

The records of 356 patients with invasive bladder cancer, operated on at three Chinese medical institutes, were reviewed. The Cox proportional hazards regression model was used to assess the clinical and pathological variables affecting disease-free survival (DFS). The regression coefficients determined by Cox regression analysis were used to construct a predictive index (PI). PI was used to categorize the patients into different risk groups. Kaplan-Meier survival curves followed with log-rank test were plotted to compare the difference.

RESULTS

Tumor configuration (RR = 1.60, P = 0.01), multiplicity (RR = 1.41, P = 0.04), histological subtype (RR = 2.13, P < 0.01), tumor stage (RR = 2.50, P < 0.01), tumor grade (RR = 2.35, P < 0.01), node status (RR = 2.48, P < 0.01), and neoadjuvant chemotherapy (RR = 0.46, P = 0.02), had independent prognostic significance for DFS. PI = 0.47 x (configuration) + 0.34 x (multiplicity) + 0.76 x (tumor histological subtype) + 0.92 x (stage) + 0.86 x (grade) + 0.91 x (node status) - 0.79 x (neoadjuvant chemotherapy). The range of PI was -0.32 to 6.52, which was equally divided into three risk groups with significant differences on Kaplan-Meier curves and a log-rank test (P < 0.01). Meanwhile, the patient's probability of survival could be calculated by PI.

CONCLUSIONS

Seven factors (tumor configuration, multiplicity, histological subtype, tumor stage, tumor grade, node status, neoadjuvant chemotherapy) affect the prognosis after radical cystectomy (RC) for invasive bladder cancer. PI can be used to optimize the individual comprehensive therapy. Given fewer perioperative complications, fast recovery from surgery and relatively satisfactory quality of life, ureterocutaneostomy, and ileal conduit are suitable for the patients with short expected life spans.