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Updated: Nov 20, 2025
Determination of Protein Expression Level in Cultured Cells by Immunocytochemistry on Paraffin-embedded Cell Blocks
Published on: May 20, 2018
A novel evaluation method for Ki-67 immunostaining in paraffin-embedded tissues
Eliane Pedra Dias1,2, Nathália Silva Carlos Oliveira3,4, Amanda Oliveira Serra-Campos3
1Unidade Integrada de Patologia Especializada (UniPE), Postgraduate Program in Pathology, Pathological Anatomy Service of Hospital Universitário Antônio Pedro, Universidade Federal Fluminense, Niterói, RJ, 23033-900, Brazil. elianepedra@hotmail.com.
This study introduces a new classification for Ki-67 nuclear patterns, potentially linking expression dynamics to the cell cycle for improved cancer prognosis and personalized therapy.
Area of Science:
- Oncology
- Cell Biology
- Pathology
Background:
- The Ki-67 labeling index is a standard measure of tumor aggressiveness.
- The heterogeneous pattern of Ki-67 nuclear positivity lacks established diagnostic or prognostic value.
- Understanding Ki-67 expression patterns is crucial for cancer research.
Purpose of the Study:
- To develop a classification system for Ki-67-positive nuclear patterns.
- To investigate the scientific evidence for Ki-67 expression throughout the cell cycle.
- To create a protocol for applying this classification in squamous epithelium with varying proliferative activities.
Main Methods:
- Empirical observation of immunohistochemistry-stained paraffin sections.
- Literature review on Ki-67 expression and cell cycle.
- Development of a semi-automatic protocol for quantifying Ki-67 immunostaining patterns.
- Inter- and intraobserver reliability testing.
Main Results:
- A classification of Ki-67 nuclear positivity patterns (NP1-NP4, mitosis) was created.
- High intraobserver reliability (Spearman's rho > 0.9) and moderate interobserver agreement (k = 0.523) were achieved.
- Non-malignant epithelium showed significantly higher NP1 patterns compared to carcinoma in situ and invasive carcinoma (p < 0.05).
Conclusions:
- Proposed classification of Ki-67 patterns offers a novel approach to evaluating its expression.
- The pattern of Ki-67 expression may correlate with cell cycle dynamics.
- Further research is needed to validate this classification for cancer prognosis and personalized therapy.
