Bladder cancer

lncRNA MIR4435-2HG Accelerates the Development of Bladder Cancer through Enhancing IQGAP3 and CDCA5 Expression

Background. Bladder cancer (BCa) is one of the most prevalent cancers occurring in the urinary system. Long noncoding RNAs (lncRNAs), in recent years, have emerged as crucial regulators in various biological processes of tumors. Aim. To identify the role of MIR4435-2 host gene (MIR4435-2HG) and uncover its molecular mechanism in BCa. Methods. Firstly, quantitative real-time PCR (RT-qPCR) analysis was used to examine MIR4435-2HG expression in BCa cells. Cell Counting Kit-8 (CCK-8), 5-ethynyl-2 $\prime$ -deoxyuridine (EdU), wound healing, and transwell assays were implemented to identify the role of MIR4435-2HG in BCa. RNA-binding protein immunoprecipitation (RIP), RNA pull down, and luciferase reporter assays were applied to explore the potential mechanism of MIR4435-2HG in BCa. Results. MIR4435-2HG was highly expressed in BCa. Moreover, MIR4435-2HG silencing abrogated BCa cell proliferation, migration, and invasion. In terms of underlying mechanism, MIR44352HG acted as a microRNA-2467-3p (miR-2467-3p) sponge to control the expression of IQ motif containing GTPase activating protein 3 (IQGAP3) and cell division cycle associated 5 (CDCA5), resulting in activation of the rat sarcoma virus (Ras)/rapidly accelerated fibrosarcoma (Raf)/mitogen-activated protein kinase (MEK)/extracellular signal-regulated kinase (ERK) and PI3K/AKT/mTOR signaling pathways. Conclusion. MIR4435-2HG involves in the progression of BCa, which might provide novel insights for BCa treatment.

Tumor size predicts the survival of patients with pathologic stage T2 bladder carcinoma: a critical evaluation of the depth of muscle invasion

BACKGROUND

Accurate examination of radical cystectomy specimens is critical for stratifying patients into prognostically important groups and determining the need for adjuvant treatment. Evidence has accumulated that cancers invading the superficial muscle wall (T2a) behave similarly to those invading the deep muscle wall (T2b). Quantitative analysis of the depth of invasion in relation to patient outcome is needed.

METHODS

The authors systematically evaluated the depth of invasion by micrometer measurement and its relation to the survival of 64 patients with bladder carcinoma pathologic classification as pT2 who had long term follow-up after radical cystectomy. Numerous clinical and pathologic variables were analyzed with univariate and multivariate Cox proportional hazards models. The mean age of patients was 64 years, and their mean follow-up was 8.3 years.

RESULTS

There was no significant difference in clinical outcome between patients with T2a carcinoma and those with T2b. Lymph node metastasis and tumor size were each significantly associated with distant metastasis free and cancer specific survival. Ten-year distant metastasis free and cancer specific survival were 100% and 94%, respectively, for patients with tumors <3 cm (P = 0.006) and 68% and 73%, respectively, for patients with tumors > or = 3 cm (P = 0.005). After adjustment for lymph node status, tumor size maintained significance in predicting distant metastasis free survival (risk ratio, 1.5; 95% confidence interval, 1.1-2.0; P = 0.009) and cancer specific survival (risk ratio, 1.5; 95% confidence interval, 1.1-1.9; P = 0.01). Age was associated with recurrence free survival and all-cause survival. None of the other variables, including gender, vascular invasion, presence of carcinoma in situ, pathologic classification (T2a vs. T2b), depth of invasion, depth of muscle invasion, ratio of depth of invasion to bladder wall thickness, and percentage of muscle wall invasion, were significantly associated with patient outcome.

CONCLUSIONS

The findings of this study indicate that the subclassification of T2 bladder carcinoma by depth of muscle invasion is of no prognostic value; conversely, tumor size, an easily measured factor, is predictive of distant metastasis free and cancer specific survival.

Non-invasive detection of malignancy by identification of unusual CD44 gene activity in exfoliated cancer cells

OBJECTIVE

To investigate non-invasive detection of cancer by testing for unusual CD44 gene activity in a clinical sample as an indicator of exfoliated tumour cells.

DESIGN

Case-control study.

SUBJECTS

44 unselected, consecutive patients with bladder cancer and 46 people with no evidence of neoplasia.

MAIN OUTCOME MEASURE

Presence or absence of large CD44 gene products containing exon 6 derivatives in urine samples.

RESULTS

Novel abnormalities in the pattern of expression of this gene, seen specifically in tumour tissue, led to cloning of a newly recognised coding region in it (exon 6). This was tested as a probe for detection of exfoliated malignant cells in naturally voided urine. CD44 gene products extracted from the urine and amplified with polymerase chain reaction contained predicted electrophoretic band of 735 base pairs in 40 of the 44 patients with bladder cancer (sensitivity 91%). Products from 38 of the 46 people with no evidence of neoplasia showed no such band (specificity 83%).

CONCLUSIONS

Unusual activity of the CD44 locus in neoplasia and malignancy is confirmed, and techniques for the analysis of such activity can enable non-invasive investigation of patients for primary or recurrent bladder cancer or for other tumours that shed neoplastic cells into body fluids.

Staging of bladder cancer

The definitive diagnosis of bladder cancer is established at cystoscopic examination and confirmed by means of a transurethral biopsy. A careful bimanual palpation of the bladder under anesthesia is an integral part of the initial assessment of each patient. The most important part of the assessment of patients with bladder cancer is a thorough pathologic examination of the biopsy material establishing the histologic type of tumor, histologic grade, tumor configuration, depth of invasion of the bladder wall, and depth of the bladder wall available for assessment. If possible, the size of the tumor and the presence of associated carcinoma in situ should also be reported. Imaging studies play a smaller role in the clinical staging of bladder cancer. However, when initial staging procedures point to invasion of the muscularis propria, chest X-ray, bone scan, and computed tomography scan of the abdomen and pelvis may provide valuable information about possible metastases. Whereas the clinical staging is essential to select and evaluate therapy, the pathologic stage (pTNM) provides the most precise data with which to estimate prognosis and calculate end results. The pathologic assessment entails resection of the primary tumor or a biopsy adequate to evaluate the highest pT category, removal of lymph nodes adequate to validate the absence of regional lymph node metastasis, as well as biopsy and microscopic examination for assessment of distant metastases. Although numerous factors have an impact on the behaviour of the malignancy, in bladder cancer the anatomic extent of disease reflected in the current staging classification remains the most powerful indicator of outcome.

Deranged activity of the CD44 gene and other loci as biomarkers for progression to metastatic malignancy

About one in three people in modern industrialised countries die of the consequences of malignant tumours or are found to carry an unsuspected one at the time of autopsy. Early resection of such lesions and appropriate adjuvant therapy is very effective in curing the disease. There is therefore a strong clinical incentive to find effective methods of early diagnosis, assessment of prognosis and treatment of neoplastic lesions and research on this topic is directed at a numerically significant medical problem. Recently it has been found that many human tumours show severe abnormalities in the expression of the CD44 gene which increase with progression to metastatic malignancy. By alternative splicing mechanisms this gene codes for a family of heavily glycosylated cell surface proteins involved in many important cellular activities. In neoplasia there is gross overexpression of various products of the gene associated with disorderly splicing, which can be detected in clinical samples with the sensitive technique of reverse transcription-polymerase chain reaction (RT-PCR). These disturbances begin early in the neoplastic process and can be detected in very small biopsy samples. It has also been shown that it is possible to achieve non-invasive diagnosis of malignancy by analysis of CD44 expression in exfoliated cells in body fluids and waste products. The potential significance of these observations for early diagnosis of symptomatic cancer and for screening of the population for asymptomatic lesions are readily seen and await further investigation. Separate work in our laboratory has succeeded in DNA-mediated transfer of metastatic capability through two rounds of transfection into non-metastatic tumour cells and a metastasis-associated human DNA fragment has been recovered from the transfectants and sequenced. Using primers designed to anneal to a coding region identified by computer analysis within the novel sequence, it has been shown with RT-PCR that it is heavily expressed in metastatic cancer tissues, but not in corresponding normal ones. This could be of value in assessing the prognosis of patients using small biopsy samples from their primary tumours and the potential of this sequence for such purposes and for possible therapeutic intervention is currently being explored. Recent work in several laboratories has shown that elevated expression of certain other specific growth factor genes, including c-met and EGFR, correlates with metastatic capability. Combined evaluation of such markers in further studies will in time give useful information on the prognosis of individual patients to guide therapeutic decisions and the implications of these recent advances for clinical practice and future research are discussed below.