Correlation of Ag-NOR protein measurements with prognosis in canine transmissible venereal tumour

Avaliação da técnica de coloração AgNOR em testículos de ovinos

A coloração pela prata das regiões organizadoras de nucléolos (NORs) é caracterizada por marcar proteínas ligadas ao ácido ribonucleico ribossômico, avaliando a proliferação em células normais ou neoplásicas. Objetivou-se estudar, em testículos de ovinos obtidos em matadouro, a validade do uso da técnica de coloração pela prata (AgNOR) na identificação das regiões organizadoras de nucléolo (NORs) em células saudáveis da linhagem espermatogênica. Utilizaram-se 43 pares de testículos de ovinos mestiços entre seis e 10 meses de idade. Testes de Wilcoxon e Spearman foram empregados, com nível de 5%. As médias das NORs nas células das gônadas direita e esquerda foram, respectivamente: espermatogônia (8,77±1,14 e 9,04±0,96), espermatócitos (4,99±2,00 e 6,20±2,07; P<0,05), Leydig (8,05±2,82 e 7,89±2,29) e Sertoli (8,07±1,88 e 7,61±2,16; P<0,05). Houve correlação (P<0,05) entre os lados para o número de NORs: espermatócitos x Leydig (0,49); espermatócitos x Sertoli (0,49) e Leydig x Sertoli (0,96). Conclui-se ser válido o emprego da técnica AgNOR para avaliar o potencial proliferativo das células saudáveis em testículos de ovinos com prática execução e baixo custo.

Cell proliferation markers in the transplanted canine transmissible venereal tumor

Adult male mongrel dogs were subcutaneously transplanted with the canine transmissible venereal tumor (TVT) on the hypogastric region. Twelve specimens of tumors were collected, half during the proliferative phase and the other half during the regressive phase. Fragments of the tumor were fixed in 10% buffered formalin and routinely processed for light microscopy. Sections of 4µm were stained by Schorr or AgNOR or either immunostained for MIB1 (Ki67). Schorr stain, AgNOR and MIB1 showed an increased proliferative activity through mitotic index, nuclear argyrophilic protein stain and cycling tumoral cells in the growing tumors, respectively. All of the three cell proliferation markers were able to distinguish the TVT in both evolution phases. MIB1 monoclonal antibody was the best in the morphologic evaluation of growth and regression of TVT. This resulted in higher values than AgNORs counting and mitotic index. MIB1 immunostaining was the most effective parameter of the proliferative activity of TVT. However, a significant correlation has been detected only between mitosis counting and AgNORs.

Computerized Cytomorphometric Analysis of Nuclear Area, Nuclear Perimeter and Mean Nuclear Diameter in Spontaneous Canine Mammary Gland Tumours

Fifty-two spontaneous canine mammary gland tumours (fibroadenomas (n=8), tubulopapillary carcinomas (n=9), solid carcinomas (n=6), anaplastic carcinomas (n=7), fibrosarcomas (n=9), liposarcomas (n=9) and osteosarcomas (n=4) were analysed by computer-assisted nuclear morphometry in Hemacolor-stained cytological specimens. Computerized cytomorphometry was performed and the nuclear area, nuclear perimeter and mean nuclear diameter of investigated tumours were assessed. A minimum of 100 nuclei per lesion were examined. The statistical analysis revealed statistically significant differences between benign and malignant neoplasms. The results indicated that computer-assisted nuclear morphometry could be used as an additional method for differentiation of benign from malignant canine mammary gland tumours in cytological specimens.

Prognostic and predictive markers in canine tumours: rationale and relevance. A review

Cancer is one of the most common causes of death in dogs. The availability of multiple treatment modalities and novel therapeutic targets make the correct diagnosis, prognostic stratification, and the identification of treatment effect predictive factors an issue of major debate in cancer management. Selection of high and low risk patients and the type of systemic or local treatment is important in cancer management. The search for better prognostic markers and predictive factors is now focused on the molecular mechanisms which underlie tumour behaviour, such as altered cell cycle progression, proliferation, apoptosis, and angiogenesis. The ultimate goal is to identify reliable markers that can accurately diagnose and stage a tumour and predict tumour's clinical behaviour, prognosis and response to therapy. In this review, the current state of prognostication in canine tumours and promising new molecular markers are discussed. The markers are allocated to four groups according to their function: (i) proliferation markers, (ii) apoptosis, (iii) extracellular matrix and cell adhesion molecules, (iv) angiogenesis and (v) cell cycle regulators. Clinicopathological factors and histopathological grading remain the most practical parameters in decision-making. Although experimental research has shown that molecular markers have a good potential to be used as diagnostic, prognostic or predictive markers in canine tumours, insufficient evidence exists on their efficacy for routine use in veterinary oncology.

Diagnostic pathology for the cancer patient

It is necessary to have a cooperative relationship between the clinician and the pathologist, because information from both is critical for determining the best case management and favorable prognosis. The principle roles of the veterinary pathologist are to describe the submitted tissues, to determine the nature of the tumor, and to assess completeness of surgical margins. Recently, the Council of the American College of Veterinary Pathologists (ACVP) appointed an ad hoc committee on oncology to evaluate oncologists' needs by polling members of the Veterinary Cancer Society (VCS). The committee's vision was to review morphologic, immunologic, and molecular techniques so that veterinary pathologists could meet the current and future diagnostic and prognostic needs of oncologic veterinarians. The factors determined to be most important to the VCS members in selecting a diagnostic pathology provider included, in order of importance: (1) reliability of results; (2) short turnaround-time; (3) easy access for consultation; (4) rapport with pathologist; (5) convenience of service; and (6) cost of service. This manuscript will attempt to review improved morphologic, immunologic, and molecular techniques to provide for the future diagnostic and prognostic needs of oncologic veterinarians.

Argyrophilic nucleolar organiser regions (AgNORs) count as indicator of post-surgical prognosis in feline mammary carcinomas

Feline mammary carcinomas (FMC) were surgically resected from 51 cats to verify that the nucleolar organiser regions (AgNORs) count is related to the post-surgical survival time (PST). After one year post-surgery, 27 cats (group A) were still alive (52.9 per cent) while (41.7 per cent) (group B) had died as a consequence of FMC. Formalin-fixed, paraffin wax-embedded histological sections were stained with silver nitrate and the AgNORs were then counted at x 100 oil immersion objective. In FMC AgNORs count ranged from 1.2 to 12.1 (6.10+/-2.3). A statistically significant difference (P=0.000112) in the AgNORs count was found between cats from group A and group B. No other statistically significant differences were found between group A and B. AgNORs count was not correlated to age or different histological type, according to the WHO classification. Using this technique it is possible to identify two populations of FMC with a statistically significant difference in the PST.

In vitro effect of ciprofloxacin on HT-29 human colon carcinoma cell line: assessment of cell proliferation by thymidine uptake and silver nucleolar organizer regions (AgNOR) histomorphometry

In an in vitro study, the effect of ciprofloxacin was examined on proliferation of HT-29 human colon carcinoma cell line. Cell proliferation was measured by 3H-thymidine uptake and silver nucleolar organizer region (AgNOR) histomorphometry. A significant increase in [3H]thymidine incorporation (p < 0.05) parallel with a significant increase in the mean AgNOR clusters/cells (p < 0.01) was noted after 5 days of cell exposure to ciprofloxacin. It is suggested that the assessment of AgNOR variables is useful in examination of quinolone effect on HT-29 human colon carcinoma cell proliferation.