[Ki-67 -- new faces of an old player]

Histologic correlation of expression of Ki-67 in squamous cell carcinoma of the glottis according to the degree of cell differentiation

Introduction

Squamous cell carcinoma is the most common neoplasm of the larynx and glottis, and its prognosis depends on the size of the lesion, level of local invasion, cervical lymphatic spread, and presence of distant metastases. Ki-67 (MKI67) is a protein present in the core, whose function is related to cell proliferation.

Aim

To evaluate the expression of marker Ki-67 in squamous cell carcinoma of the larynx and glottis and its correlation to pathological findings.

Methods

Experimental study with immunohistochemistry analysis of Ki-67, calculating the percentage of the cell proliferation index in glottic squamous cell carcinomas.

Results

Sixteen cases were analyzed, with six well-differentiated and 10 poorly/moderately differentiated tumors. There was a correlation between cell proliferation index and degree of cell differentiation, with higher proliferation in poorly/moderately differentiated tumors.

Conclusion

The cell proliferation index, as measured by Ki-67, may be useful in the characterization of histological degree in glottic squamous cell tumors.

The role of FDG-PET-CT in the evaluation of primary systemic therapy in breast cancer: links between metabolic and pathological remission

Introduction: FDG-PET-CT is highly sensitive in detection of viable tumour tissue, giving an importance for that in oncological diagnostics. Aim: The authors analysed retrospectively the relationship between metabolic response and changes in Ki-67, a proliferation marker. Methods: Staging FDG-PET-CT scans (before and after therapy) SUVs (Standardized Uptake Value), and morphological changes in the primary tumour and axillary lymph node region were evaluated in 30 patients with breast cancer. Calculated ΔSUV were compared with Ki-67 proliferation marker (measured in biopsies and surgical specimens). Results: The decrease of SUV and size were significant in the primary tumour and the axillary lymph node region. Decrease of Ki-67 was significant. Significant correlation was found between Ki-67 and SUV before therapy, initial Ki-67 and ΔSUV, and ΔKi-67 and ΔSUV. Conclusions: The metabolic changes were more sensitive in the measurement of the therapeutic response than morphological remission, and they correlated well with the pathological response, in not standardized clinical conditions even. Orv. Hetil., 2012, 153, 1958–1964.

Cell type-dependent gene transcription profile in a three-dimensional human skin tissue model exposed to low doses of ionizing radiation: implications for medical exposures

The concern over possible health risks from exposures to low doses of ionizing radiation has been driven largely by the increase in medical exposures, the routine implementation of X-ray backscatter devices for airport security screening, and, most recently, the nuclear incident in Japan. Because of a paucity of direct epidemiological data at very low doses, cancer risk must be estimated from high dose exposure scenarios. However, there is increasing evidence that low and high dose exposures result in different signaling events and may have different response mechanisms than higher doses. We have examined the radiation-induced temporal response after exposure to 10 cGy of an in vitro three dimensional (3D) human skin tissue model using microarray-based transcriptional profiling. Cell type-specific analysis showed significant changes in gene expression with the levels of >1,400 genes altered in the dermis and >400 genes regulated in the epidermis. The two cell layers rarely exhibited overlapping responses at the mRNA level. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) measurements validated the microarray data in both regulation direction and value. Key pathways identified relate to cell cycle regulation, immune responses, hypoxia, reactive oxygen signaling, and DNA damage repair. The proliferation status as well as the expression of PCNA was examined in histological samples. We discuss in particular the role of proliferation, emphasizing how the disregulation of cellular signaling in normal tissue may impact progression toward radiation-induced secondary diseases.

Relationship between characteristics of CD44+/ki-67- colorectal cancer stem cells and clinicopathological characteristics in patients with colorectal cancer

AIM: To investigate the number, location, distribution and staining features of CD44⁺/ki-67^- colorectal cancer stem cells and to analyze their relation with clinicopathological characteristics in patients with colorectal carcinoma.

METHODS: Streptavidin-HRP immunohistochemical staining, double immunohistochemical staining and hematoxylin-eosin staining were performed to detect the expression of CD44 and ki-67 in 10 cases of normal mucosal tissue, 15 cases of adenoma with atypical hyperplasia, 59 cases of colorectal carcinoma, and human colon cancer cell line SW620. The number, location, distribution and staining features of CD44⁺/ki-67^- colorectal cancer stem cells were observed, and their relation with clinicopathological characteristics was analyzed.

RESULTS: The number of CD44⁺/ki-67^- tumor cells accounted for 0.1%-25.0% (average 5.82%) of all tumor cells, and the cells were mainly distributed in the sides of the basal membrane or common wall of glands. These cells had round or oval nuclei that were consistent in size, and contained deep stained chromatin and less cytoplasm. These features are consistent with those of stem cells in the intestinal crypts. The number of CD44⁺/ki-67^- tumor cells was significantly correlated with depth of cancer infiltration (χ² = 1.851, P < 0.05) and lymph node metastasis (χ² = -4.113, P < 0.01).

CONCLUSION: CD44⁺/ki-67^- are suitable specific markers for tumor stem cells and can be used for tumor stem cell isolation, targeted therapy, individualized treatment, prediction of tumor metastasis, and estimation of prognosis in patients with colorectal cancer.