Anatomical features of the urethra and urinary bladder catheterization in female mice and rats. An essential translational tool.

PURPOSE: To present fundamental anatomical aspects and technical skills necessary to urethra and urinary bladder catheterization in female mice and rats. METHODS: Urethral and bladder catheterization has been widely utilized for carcinogenesis and cancer research and still remains very useful in several applications: from toxicological purposes as well as inflammatory and infectious conditions to functional aspects as bladder dynamics and vesicoureteral reflux, among many others. RESULTS: Animal models are in the center of translational research and those involving rodents are the most important nowadays due to several advantages including human reproducibility, easy handling and low cost. CONCLUSIONS: Although technical and anatomical pearls for rodent urethral and bladder access are presented as tackles to the advancement of lower urinary tract preclinical investigation in a broaden sight, restriction to female animals hampers the male microenvironment, demanding future advances.

Anatomical features of the urethra and urinary bladder catheterization in female mice and rats. An essential translational tool / Características anatômicas da cateterização da uretra e bexiga de camundongos e ratos fêmeas. Instrumento essencial na pesquisa pré clínica

PURPOSE: To present fundamental anatomical aspects and technical skills necessary to urethra and urinary bladder catheterization in female mice and rats. METHODS: Urethral and bladder catheterization has been widely utilized for carcinogenesis and cancer research and still remains very useful in several applications: from toxicological purposes as well as inflammatory and infectious conditions to functional aspects as bladder dynamics and vesicoureteral reflux, among many others. RESULTS: Animal models are in the center of translational research and those involving rodents are the most important nowadays due to several advantages including human reproducibility, easy handling and low cost. CONCLUSIONS: Although technical and anatomical pearls for rodent urethral and bladder access are presented as tackles to the advancement of lower urinary tract preclinical investigation in a broaden sight, restriction to female animals hampers the male microenvironment, demanding future advances.

OBJETIVO: Apresentar aspectos anatômicos fundamentais e habilidades técnicas necessárias para cateterismo da uretra e bexiga em ratos e camundongos fêmeas. MÉTODOS: Cateterismo vesical tem sido amplamente utilizado na pesquisa do câncer e carcinogênese, além de várias outras aplicações, desde fins toxicológicos, condições inflamatórias e infecciosas até aspectos funcionais como a dinâmica vesical e refluxo vesico-ureteral, entre muitos outros. RESULTADOS: Os modelos animais estão no centro da investigação de translação e os roedores são os mais importantes devido a várias vantagens, incluindo reprodutibilidade humana, o fácil manuseio e baixo custo. CONCLUSÕES: Apesar de permitir o desenvolvimento da investigação pré-clínica do trato urinário inferior, o modelo se restringe aos animais do sexo feminino, de modo que avanços futuros são necessários.

The N-Myc-DLL3 cascade is suppressed by the ubiquitin ligase Huwe1 to inhibit proliferation and promote neurogenesis in the developing brain.

Self-renewal and proliferation of neural stem cells and the decision to initiate neurogenesis are crucial events directing brain development. Here we show that the ubiquitin ligase Huwe1 operates upstream of the N-Myc-DLL3-Notch pathway to control neural stem cell activity and promote neurogenesis. Conditional inactivation of the Huwe1 gene in the mouse brain caused neonatal lethality associated with disorganization of the laminar patterning of the cortex. These defects stemmed from severe impairment of neurogenesis associated with uncontrolled expansion of the neural stem cell compartment. Loss- and gain-of-function experiments in the mouse cortex demonstrated that Huwe1 restrains proliferation and enables neuronal differentiation by suppressing the N-Myc-DLL3 cascade. Notably, human high-grade gliomas carry focal hemizygous deletions of the X-linked Huwe1 gene in association with amplification of the N-myc locus. Our results indicate that Huwe1 balances proliferation and neurogenesis in the developing brain and that this pathway is subverted in malignant brain tumors.

[Molecular protocol for HER2/neu analysis in breast carcinoma]. / Protocolo de estudio molecular del oncogén HER2/neu en el carcinoma de mama.

BACKGROUND: The HER2/neu proto-oncogene is frequently over-expressed in breast cancer and serves as a biological target for trastuzumab therapy. However, there is no consensus regarding the technical aspects to be used to define HER2/neu status in clinical practice. METHODS: The present study was conducted to address this critical issue by prospectively analysing a large cohort of breast cancer patients (n = 222) and using a variety of methods. To define HER2/neu expression, detection of its encoded protein (p185) was performed by comparative immunohistochemical (IHC) analysis using two mouse monoclonal antibodies (mAb CB11 and mAb TAB250). To assess HER2/neu gene amplification, fluorescent in situ hybridisation (FISH) assays with gene-specific probes were conducted. All procedures were applied to de-paraffinised tissue sections of breast tumour samples. RESULTS: Results showed that mAb CB11 had increased sensitivity and specificity (62.5% and 93.4%, respectively) compared to mAb TAB250 (40% and 76.4%, respectively) in defining HER2/neu amplification. We conclude that HER2/neu measurement by IHC using mAb CB11 is an appropriate strategy which provides a high negative predictive value (95.5%) for HER2/neu amplification in cases with low or undetectable p185 expression. Conversely, mAb CB11 has a high positive predictive value (96.2%) for HER2/neu amplification in cases with p185 overexpression. However, cases with moderate p185 expression need to be considered as inconclusive. In such cases, it is necessary to use FISH measurement to evaluate HER2/neu amplification. It is also advisable to conduct FISH if there is discordance between p185 expression and the histopathology classification of the lesion, or molecular profile of the tumour. Finally, even though the false positive rate of IHC assay is <5%, the toxicity and cost of trastuzumab therapy suggest that FISH be used systematically prior to implementation of treatment. CONCLUSION: We suggest the use of a molecular protocol for HER2/neu analysis in this type of tumor.