MCM - 2 and Ki - 67 as proliferation markers in renal cell carcinoma: A quantitative and semi - quantitative analysis

ABSTRACT Introduction/Background: Fuhrman nuclear grade is the most important histological parameter to predict prognosis in a patient of renal cell carcinoma (RCC). However, it suffers from inter-observer and intra-observer variation giving rise to need of a parameter that not only correlates with nuclear grade but is also objective and reproducible. Proliferation is the measure of aggressiveness of a tumour and it is strongly correlated with Fuhrman nuclear grade, clinical survival and recurrence in RCC. Ki-67 is conventionally used to assess proliferation. Mini-chromosome maintenance 2 (MCM-2) is a lesser known marker of proliferation and identifies a greater proliferation faction. This study was designed to assess the prognostic significance of MCM-2 by comparing it with Fuhrman nuclear grade and Ki-67. Material and Methods: n=50 cases of various ages, stages, histological subtypes and grades of RCC were selected for this study. Immunohistochemical staining using Ki-67(MIB-1, Mouse monoclonal antibody, Dako) and MCM-2 (Mouse monoclonal antibody, Thermo) was performed on the paraffin embedded blocks in the department of Morbid anatomy and Histopathology, University of Health Sciences, Lahore. Labeling indices (LI) were determined by two pathologists independently using quantitative and semi-quantitative analysis. Statistical analysis was carried out using SPSS 20.0. Kruskall-Wallis test was used to determine a correlation of proliferation markers with grade, and Pearson's correlate was used to determine correlation between the two proliferation markers. Results: Labeling index of MCM-2 (median=24.29%) was found to be much higher than Ki-67(median=13.05%). Both markers were significantly related with grade (p=0.00; Kruskall-Wallis test). LI of MCM-2 was found to correlate significantly with LI of Ki-67(r=0.0934;p=0.01 with Pearson's correlate). Results of semi-quantitative analysis correlated well with quantitative analysis. Conclusion: Both Ki-67 and MCM-2 are markers of proliferation which are closely linked to grade. Therefore, they can act as surrogate markers for grade in a manner that is more objective and reproducible.

Immunoexpression of cell proliferation markers in oral squamous cell carcinoma / Inmunoexpresiones de marcadores de proliferación celular en carcinoma de células escamosas orales

This study aimed to assess the immunoexpression of cell proliferation markers (Ki-67 and Mcm-2) in oral tongue cancer, correlating it with patients' age and prognostic indicators. Sample was composed of 22 cases under 40 years and 22 over 50 years of age. Clinical staging and histological grade of malignancy were obtained. Cell proliferation was evaluated through labeling indices. Statistical analysis was performed (p<0.05 for statistical significance). Most young patients were stages III/IV (n=13/65 %) and most older patients were stages I/II (n=11/61.1 %) (p>0.05). Mean Ki-67-LI in young and older patients was 42.4 % and 44.15 %, respectively (p>0.05). Mean Mcm-2-LI was higher in older (63.6 %) than in young patients (55.75 %) (p<0.05). We found that young patients presented more aggressive lesions in comparison to older patients, however Mcm-2 expression was significantly higher in older than in young patients. SCC of tongue can be more aggressive in young patients, and this may not be related to cell proliferation. Our findings for Mcm-2 LI and Ki-67 LI suggests that Mcm-2 could be a more sensitive marker for cell proliferation.

Este estudio tuvo como objetivo evaluar la inmunoexpresión de marcadores de proliferación celular (Ki-67 y Mcm-2) en el cáncer de lengua oral, correlacionándolo con la edad de los pacientes y los indicadores pronósticos. La muestra estuvo compuesta por 22 personas menores de 40 años y 22 personas mayores de 50 años. Se identificaron los estadios clínicos y el grado histológico de malignidad. La proliferación celular se evaluó mediante índices de marcado. Se realizó análisis estadístico (p <0,05 para significación estadística). La mayoría de los pacientes jóvenes eran estadios III / IV (n = 13/65 %) y la mayoría de los pacientes mayores eran estadios I / II (n = 11 / 61,1 %) (p> 0,05). La media de Ki-67-LI en pacientes jóvenes y mayores fue 42,4% y 44,15%, respectivamente (p> 0,05). La media de Mcm-2-LI fue mayor en pacientes mayores (63,6 %) que en pacientes jóvenes (55,75 %) (p <0,05). Se encontró que los pacientes jóvenes presentaron lesiones más agresivas en comparación con los pacientes mayores, sin embargo la expresión de Mcm-2 fue significativamente mayor en pacientes mayores que en pacientes jóvenes. SCC de la lengua puede ser más agresivo en pacientes jóvenes, y esto no puede estar relacionado con la proliferación celular. Nuestros hallazgos para Mcm-2 LI y Ki-67 LI sugieren que Mcm-2 podría ser un marcador más sensible para la proliferación celular.

Comparison of proliferative activity of epithelial cells between the follicles of impacted teeth / Comparación de la actividad proliferativa de las células epiteliales entre los folículos de dientes impactados

The aim of this comparative observational study was to compare the proliferative activity of dental follicles surrounding impacted maxillary canines and mandibular third molars. Following extraction, forty follicles of the impacted mandibular third molars and 40 follicles of the impacted maxillary canines were removed. Epithelial cell proliferative activity of these samples was assessed using immunohistochemical labeling for Ki-67, minichromosome maintenance 2 (MCM-2) protein and epithelial growth factor receptor (EGFR). Intensity and extent of Ki-67, MCM-2 and EGFR expressions were evaluated by a scoring formula. The lining epithelium of the maxillary canine follicles had mean scores of 4.65±0.27 for Ki-67, 1.25±0.33 for MCM-2 and 7.30±0.23 for EGFR which were not significantly different than those expressed in the mandibular third molar follicles (4.46±0.26 for Ki-67, 1.39±0.33 for MCM-2 and 7.21±0.20 for EGFR). The expression of Ki-67 and MCM-2 could not be detected in the epithelial remnants within the connective tissue in both groups. EGFR expression, detected in the epithelial remnants in both groups, was not significantly different (7.28±0.14 in the canine group as opposed to 7.21±0.16 in the third molar group). Based on these findings, it can be deduced that impacted mandibular third molars and maxillary canines carry similar risk of pathology development.

El objetivo fue comparar la actividad proliferativa de los folículos dentarios que rodean a dientes caninos maxilares y terceros molares mandibulares impactados. Luego de realizada la extracción dentaria, se removieron 40 folículos dentarios de los terceros molares mandibulares impactados y 40 de caninos maxilares impactados. Se evaluó la actividad proliferativa de las células epiteliales de estas muestras mediante marcaje inmunohistoquímico para Ki-67, para la proteína de mantenimiento minicromosoma 2 (MCM-2) y para el receptor del factor de crecimiento epitelial (EGFR). Se evaluó la intensidad y extensión de Ki-67, MCM-2 y las expresiones de EGFR mediante una fórmula de puntuación. El epitelio de revestimiento de los folículos correspondientes a los caninos maxilares presentaron valores promedios de 4,65±0,27 para Ki-67, 1,25±0,33 para MCM-2 y 7,30±0,23 para EGFR, que no fueron significativamente diferentes de los expresados en los folículos de terceros molares mandibulares (4,46±0,26 para Ki-67, 1,39±0,33 para MCM-2 y 7,21±0,20 para EGFR). La expresión de Ki-67 y MCM-2 no pudo ser detectada en los restos epiteliales dentro del tejido conectivo en ambos grupos. La expresión de EGFR, detectada en los restos epiteliales en ambos grupos, no fue significativamente diferente (7,28±0,14 en el grupo de los caninos, y 7,21±0,16 en el grupo de los terceros molares). Sobre la base de estos resultados, se puede deducir que la retención de terceros molares y caninos maxilares conlleva un riesgo similar para el desarrollo de patología.

Expression and significance of MCM2, Ki-67 and Rb protein in laryngeal squamous cell carcinomas / 临床耳鼻咽喉头颈外科杂志

OBJECTIVE@#To investigate the expression of MCM2, Ki-67 and Rb and its biological characteristic in human laryngeal squamous cell carcinomas(LSCC).@*METHOD@#The expression of MCM2 protein and Rb protein were detected in 60 cases of LSCC, 10 cases of precarcinoma, 10 cases of vocal cord polyps and 10 cases of normal laryngeal tissues, and Ki-67 protein were detected in 60 cases of LSCC and 10 cases of normal laryngeal tissues by Elivision plus immunohistochemical staining, and analyze their relations with clinicopathological characteristics.@*RESULT@#The positive expression rate of MCM2 in LSCC was significantly higher than that in precarcinoma and normal laryngeal tissues (P < 0.05), and was positively correlated with pathological grades, clinical stages and lymph node metastases (P < 0.05) of LSCC. The positive expression rate of Rb protein in LSCC was significantly lower than that in precarcinoma and normal laryngeal tissues (P < 0.05). The expression level of MCM2 in LSCC was negatively corelated with Rb (r = -0.542, P < 0.05), the expression level of Ki-67 in LSCC (76.67%) was significantly higher than that in normal laryngeal tissues (30.00%) (P < 0.01) and the expression level of MCM2 in LSCC was positively corelated with Ki-67(r = 0.596, P < 0.01). The LI of MCM2 in the 3-year survival rate of LSCC was significantly lower than that in Ki-67 (P < 0.05).@*CONCLUSION@#Over expression of MCM2 and loss of Rb protein were related to the carcinogenesis and development of LSCC. The determination of MCM2 can be an index for estimating the level of malignancy and prognosis of LSCC.

Expression of Cdc7 and mcm2 as a marker for proliferation and prognosis in diffuse large B cell lymphoma / 中华肿瘤杂志

<p><b>OBJECTIVE</b>The aim of this study was to assess the expression of cell division cycle 7 (Cdc7) kinase and minichromosome maintenance protein 2 (MCM2) in diffuse large B cell lymphoma (DLBCL) and explore their relationship with prognosis of DLBCL patients.</p><p><b>METHODS</b>Clinical data of 60 DLBCL patients treated in our hospital from 2008.1 to 2010.1 were collected. The expression levels of Cdc7 and MCM2 in peripheral blood and bone marrow were determined by real-time PCR. A statistical analysis was carried out to evaluate their association with prognosis in DLBCL patients.</p><p><b>RESULTS</b>The 2-year survival rate of patients with high expression of peripheral blood Cdc7 was 38.3% and those with low expression 65.4% (P = 0.001). The 2-year survival rate of patients with high expression of bone marrow Cdc7 was 37.2% and those with low expression was 75.5% (P = 0.032). The 2-year survival rate of patients with high expression of MCM2 in peripheral blood was 44.0% and those with low expression was 68.2% (P = 0.025). The 2-year survival rate of patients with high expression of MCM2 in bone marrow was 39.0% and those with low expression was 63.4% (P = 0.007). A poor disease specific survival was observed in DLBCL patients with high level expression of Cdc7 and MCM2.</p><p><b>CONCLUSIONS</b>Cdc7 and MCM2 expression can be used to assess tumor proliferation and may be useful as an additional marker in combination with conventional markers in prediction of the outcome of DLBCL patients. Moreover, the Cdc7 and MCM2 signal pathway might be useful as a new approach in the treatment of refractory DLBCL lymphoma patients.</p>

The effect of childbirth on carcinogenesis of DMBA-induced breast cancer in female SD rats / 癌症

Many epidemiologic and clinical studies have indicated that the frequency of breast cancer was lower in parous women than in nulliparous women. Moreover, the incidence of breast cancer has been reported to be lower in women with early childbirth than in women with late childbirth. To verify the effect of childbirth and the age at first childbirth on carcinogenesis and progression of breast cancer, we induced breast cancer by 7,12-dimethylbenanthracene (DMBA) in 120 female Sprague-Dawley (SD) rats, and divided them into control or experimental (DMBA-treated) nulliparous, early childbirth, and late childbirth groups to observe the incidence, latency, and size of breast cancer. Argyrophilic nucleolar organizer regions (AgNOR) count and the expression of C-erbB-2, proliferating cell nuclear antigen (PCNA), Ki-67, and minichromosome maintenance protein 2 (MCM2) in breast cancer tissues were detected by immunohistochemistry. The breast cancer incidences were 95.0%, 16.7%, and 58.8% in the experimental nulliparous, early childbirth, and late childbirth groups, respectively (all P < 0.05). Between any two of these groups, the latency was significantly different, but tumor size was similar. AgNOR count and the expression of C-erbB-2, PCNA, Ki-67, and MCM2 were significantly higher in the experimental nulliparous group than in the experimental early or late childbirth groups (P < 0.05), but no significant differences were observed between the latter two groups. Taken together, the results suggest that childbirth, especially early childbirth, can reduce the incidence and postpone the onset of DMBA-induced breast cancer.

Expression of minichromosome maintenance protein 2 in colonic adenocarcinoma, adenoma and normal colonic mucosa and its clinical significance / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the expression differences of minichromosome maintenance 2 (MCM2) mRNA and protein among colon adenocarcinoma, colon adenoma and normal mucosa, and among different clinicopathological types of adenomas.</p><p><b>METHODS</b>Fifty specimens, including 33 colonic adenomas, 12 colonic adenocarcinomas and 5 normal colonic mucosa were selected. Each specimen was divided into two parts, one for immunohistochemistry and the other for real-time RT-PCR. Expression differences of MCM2 mRNA among the colonic adenocarcinoma, adenoma and normal colonic mucosa were evaluated by REST-XL software.</p><p><b>RESULTS</b>The expression of MCM2 was observed in the basal third to half of the colonic crypts in normal mucosa, while throughout the epithelium in the colonic adenocarcinomas and adenomas. However, the expression of MCM2 mRNA in the adenocarcinomas was significantly higher than that in the adenomas(P=0.001). The MCM2 mRNA expression was elevated in the adenoma with villous type, in the conditions of high-grade dysplasia, larger size, sessile morphology and in patients of older ages, but the difference was not significant by REST-XL (P>0.05).</p><p><b>CONCLUSION</b>The difference of MCM2 expression between the adenoma and the adenocarcinoma indicates its potential value in the early diagnosis of colonic cancer.</p>