Expression Of Bcl-2 Oncoprotein Research Articles

Predicting transition from oral pre-malignancy to malignancy via Bcl-2 immuno-expression: Evidence and lacunae

Bcl-2 (B cell Lymphoma −2) family comprises of both anti-apoptotic and pro-apoptotic proteins whose altered expression or change in ratio inhibits apoptosis, and promotes tumor progression. The aim of this study is to assess the usefulness of Bcl-2 in distinguishing dysplastic or malignant epithelium from non-dysplastic or normal epithelium to aid in prediction of malignant transformation potential. Material and methodStudy group comprised of 30 cases of clinically diagnosed leukoplakia (OPMD), 15 cases of Oral Squamous Cell Carcinoma (OSCC) and 5 normal tissue samples. The labeling index of Bcl-2 was analyzed in immunohistochemically stained sections. Different statistical tools were used to analyze the data and to compare Bcl-2 expression qualitatively and quantitatively among all the groups. ResultsAn increasing trend of Bcl-2 immunoexpression was observed from normal epithelium to non-dysplastic and from non-dysplastic to dysplastic lesions. In OSCC, the peripheral cells in the differentiating epithelial islands (within the connective tissue) showed Bcl-2 immuno-reactivity, which gradually decreased towards the center. In contrast, intense and diffuse Bcl-2 immuno-reactivity was seen in poorly differentiated carcinoma. But the overall Bcl-2 positivity was less in OSCC as compared to dysplastic lesions. ConclusionIncreased expression of Bcl-2 oncoprotein in sequentially progressing epithelial dysplasia and down-regulation in differentiating carcinoma (well and moderately differentiating OSCC) unveils the clinical relevance of Bcl-2 in early stages of OSCC tumorigenesis. The heterogenous expression of Bcl-2 in carcinoma with different grades of differentiation renders them unable to be used as an independent tool for predicting transition from oral pre-malignancy to malignancy.

Histopathological Evaluation and Analysis of Immunohistochemical Expression of Bcl-2 Oncoprotein in Colorectal Carcinoma.

Background & Objective:Colorectal cancer is the third most prevalent malignancy with high mortality rate, necessitating markers that predict survival and guide the treatment. Previous studies have examined the immunohistochemical expression of Bcl-2, an apoptotic marker, in colorectal carcinoma, but results have been contradictory. To evaluate the histopathological features of colorectal carcinoma, immunohistochemical expression of Bcl-2 must be analyzed to find out statistical association of Bcl-2 expression with certain prognostic factors histopathologic type, grade and TNM staging. Methods:This prospective study was conducted on the colectomy specimens of colorectal carcinoma, over a period of two years. The tumor morphology and Bcl-2 status were evaluated by immunohistochemistry in each case.Results:The study included 58 cases, with mean patient age of 47.07 years and male: female ratio of 1.89:1. Bcl-2 positivity was seen in 32.7% of the cases. Weak, moderate, and strong expression of Bcl-2 was seen in 12.1%, 12.1%, and 8.5% of cases respectively. Even though early stages of colorectal carcinoma showed greater frequency of Bcl-2 expression than advanced stages (36.3% versus 28%), however this association was not statistically significant. Conclusion:Lack of statistically significant correlation between Bcl-2 immuno-histochemical expression and prognostic parameters like tumor grade and stage, suggests that Bcl-2 immunoexpression may not be a significant prognostic marker in colorectal carcinoma.

Bcl-2 expression in reactive oral lesions with atypical epithelium and in oral epithelial dysplasia associated with carcinogen exposure.

Background:Reactive lesions of the oral cavity are nonneoplastic proliferations with very similar appearance to benign neoplastic lesions and are associated with chronic local irritation or trauma. Although these lesions are uncommonly associated with carcinogen exposure, at times, they present histopathologically with dysplastic epithelium, thus making it difficult to differentiate it from true potentially malignant disorders. Hence, the present study was conducted to evaluate the expression of Bcl-2 protein, an antiapoptotic marker, in reactive lesions with and without atypical epithelium and in true epithelial dysplasia, which clinically presents as premalignant disorders.Materials and Methods:The samples included 15 cases each of normal oral mucosa (NOM), reactive lesions with and without dysplasia and oral epithelial dysplasia (OED) associated with carcinogen exposure. All the samples were subjected to immunohistochemical staining using Bcl-2 antibody. The total number of cells in the basal and parabasal layers in each field and total number of cells expressing Bcl-2 among them and the staining intensity were assessed.Statistical Analysis:Kruskal–Wallis ANOVA test was used to compare the number of positive cells among the four groups. The comparison of average percentage of positive cells between the study groups was done using Mann–Whitney U-test.Results:The immunohistochemical staining for Bcl-2 protein was identified in few cells in the basal layers of NOM, reactive lesions without atypical epithelium and in the basal and parabasal layers in reactive lesions with atypical epithelium and OED, as a granular cytoplasmic staining and as an accentuation around the nuclear membrane. There was a gradual increase in the expression and intensity of staining from Group I to IV.Interpretation and Conclusion:The altered or increased expression of Bcl-2 oncoprotein in reactive lesions with atypical epithelium and in OED with carcinogen exposure may lead to prolonged cell survival and can be considered as an early molecular event in carcinogenesis, helping us in understanding the nature of dysplasia in reactive lesions, which was not considered during the histopathology reporting.

Clinicopathological correlation of Bcl-2 oncoprotein expression in oral precancer and cancer

Oral squamous cell carcinoma is the most common malignant tumor of the oral cavity. Normally the death of cell and the growth are active processes and depend not only on external factors but also on the expression of genes such as Bcl-2, which activate and inhibit apoptosis. The term Bcl-2 is an acronym for B-cell lymphoma/leukemia-2 genes. It has been reported that there is deregulation of Bcl-2 expression during progression from oral epithelial dysplasia to squamous cell carcinoma.Expression of this oncoprotein can be detected by immunohistochemistry. Aims and objectivesAn attempt was made to evaluate Bcl-2 oncoprotein expression in patients with oral precancer and cancer. Materials and methodsA selective prospective clinical and immunohistochemical study. Clinicopathological examination was correlated with immunohistochemical findings. The immunolocalization of Bcl-2 protein was performed using the labeled streptavidin biotin method. To visualize the reaction, 3,3-diaminobenzidine was used. ResultsBcl-2 expression was positive in 11 [36.66%, low Bcl-2 expression 3 (10.00%), moderate Bcl-2 expression 7 (23.33%), and high Bcl-2 expression 1 (3.33%)] oral cancer cases and 14 [87.50%, low expression 8 (50%), moderate expression 6 (37.50%)] precancer cases. ConclusionOn the basis of the results of our study, we conclude that positive Bcl-2 expression may be an indicator of poor prognosis in oral cancer and precancer.

Immunoexpression of Bcl-2 in Breast Carcinoma: Association with Clinicopathological Parameters

Background and Objectives: Breast cancer is the most common malignancy in women. It is an immensely heterogeneous disease, characterized by a broad variety of clinical development. The research in recent years has focused on finding new markers of prognostic significance. Bcl-2, the protein product of the Bcl-2 gene, is a member of the Bcl-2 family of proteins that play a crucial role in a complex mechanism of apoptosis. It was recently proposed that Bcl-2 could inhibit cancer progression. Aims of the study: To evaluate the role of Bcl-2 oncoprotein expression in patients with breast carcinoma and its relation with various clinic pathological parameters. Patients and Methods: Hundred cases of primary breast cancer were included in this prospective retrospective study. The cases were collected from Rizgary Teaching Hospital and Private Laboratories during a period of ten months from February to November 2013. The expression of Bcl-2 oncoprotein was evaluated immunohis to chemically; the findings were correlated with the age of the patients, size, type and grade of the tumor, lymph node status, vascular invasion, and the estrogen and progesterone receptors. Results: Bcl-2 oncoprotein was detected in 61 cases of primary breast cancer (61%). In this study the majority of estrogen and progesterone receptors positive cases, (71%) and (59%) respectively, showed positive Bcl-2 oncoprotein expression, (P=0.030) and (P=0.001) respectively. No significant correlation with the age of the patient, size, type, grade of the tumor, lymph node status nor with lymphovascular invasion could be found, (P=0.218), (P=0.410), (p=0.947), (p=0.938), (p=0.190), (P=0.370) respectively. Conclusions: Bcl-2 oncoprotein was frequently expressed in primary breast cancer. This study revealed a significant correlation between Bcl-2 and the estrogen and progesterone receptors. Our results suggest that Bcl-2 expression may be related to hormonal regulation. Larger patient study groups with a long follow up period will be helpful to clarify the prognostic significance of Bcl-2.

Expression and prognostic significance of bcl-2 apoptosis inhibitor in renal cell carcinoma

This articlepresents the study of prognostic significance of bcl-2 apoptosis inhibitor expression in renal cell carcinoma. Operation samples of 59 patients with renal cell carcinoma were studied. Average age of patients was 56,6 ± 1,3 years. 31 (52,5 %) were men , 28 (47,5 %)-women . Correlations were found between bcl-2, clinical cancer stage (r = 0,31; р = 0,02), size of tumor node (r = 0,29; р = 0,02), regional and distant metastasis ( r = 0,35; р = 0,005) and histologic tumor type (r = 0,41; р = 0,002). No correlation was found with patients ’ sex (r = 0,16; р = 0,22), age (r = 0,17; р = 0,22) and tumor grade by Furman (r = 0,19; р = 0,15). Absence of bcl- 2 expression in tumor cells can be considered as a marker of possible metastases. The results showed correlation between the marker expression and overallsurvival was. Low level of bcl-2 oncoprotein expression in tumor cells is apoorprognostic factor of fatient’s survival.

Immunohistochemical expression of Bcl-2 in oral epithelial dysplasia and oral squamous cell carcinoma.

The B cell lymphoma-2 gene is a proto-oncogene whose protein product inhibits apoptosis. Its role is associated with keeping cells alive, but not by stimulating them to proliferation, as other proto-oncogenes do. Increased expression of protein product of Bcl-2 gene appears in the early phase of carcinogenesis leading to apoptosis impairment and in consequence to the progression of neoplastic changes. To evaluate and compare the expression of Bcl-2 protein in oral epithelial dysplasia and oral squamous cell carcinoma (OSCC). Sixty cases of formalin-fixed paraffin-embedded archival specimens comprising of 30 cases of leukoplakia with oral epithelial dysplasia and 30 cases of OSCC were taken for immunohistochemical analysis using monoclonal antibody against anti-human Bcl-2 oncoprotein. Immunostaining for Bcl-2 protein was identified in basal and parabasal layers as granular cytoplasmic staining in oral epithelial dysplasia. In OSCC, Bcl-2 immunoreactivity was most prominent in the peripheral cells of the infiltrating tumor islands which diminished toward the center in well-differentiated and moderately differentiated OSCC, whereas stronger and more diffuse expression of Bcl-2 oncoprotein was seen in poorly differentiated OSCC. Overall positivity of 26.7% (8/30) was observed in oral epithelial dysplasia and 30% (9/30) in OSCC in this study. Altered expression of Bcl-2 oncoprotein may be an early molecular event which leads to prolonged cell survival, increased chances of accumulation of genetic alterations, and subsequent increase in malignant transformation potential.

Recurrent salivary pleomorphic adenoma shows increased immunohistologic expression of bcl-2 oncoprotein.

Internal cell biology, including apoptotic regulation, is presumed to play a key role in the development of recurrent pleomorphic adenoma (PA). The aim of our study was to determine the relevance of B-cell lymphoma 2 (bcl-2) oncoprotein immunoexpression and distribution in primary PA, and its recurrence. Ten primary-non-recurrent, 14 primary-to-recur, and 28 recurrences of parotid PA patients aged 19-73 (mean 40.7±16.7) years were enrolled. The bcl-2 expression was compared between groups using a semi-quantitative histoscore, defined as the multiple of the percentage of cells by the intensity of immunostaining. Widely varying bcl-2 immunoreaction was found in the epithelial areas of 91.7% of primary and 85.2% of recurrent PA. Similarly varying but much less, immunopositivity was found in the myxoid areas of 62.5% of primary and 71.4% of recurrent tumours. No obvious differences in the bcl-2 staining intensity or pattern of specific epithelial morphologic structures in either the primary-non-recurrent, primary-to-recur or recurrent tumours were found. In both the mesenchymal and epithelial areas of PA, the differences in bcl-2 immunohistoscore between the primary-non-recurrent and primary-to-recur groups were not statistically significant (P=0.62, respectively 0.51). In the mesenchymal areas, the study revealed a significantly increased histoscore in recurrent tumours compared to their corresponding primaries (P=0.01). Increased bcl-2 expression in recurrent PA suggests an exaggerated aggressiveness of that tumor. The fact that a significant difference in the histoscore was found exclusively in the myxoid component seems to accord with the reported prevalence of the latter in recurrent and metastatic PA.

Immunohistochemical Evaluation of Bcl-2 Oncoprotein in Buffalo’s Adrenal Gland

The present study was undertaken to correlate the immunohistochemical expression of Bcl-2 oncoprotein in buffalo’s adrenal gland in the young and old ages. Paraffin-embedded sections from the adrenal glands representing the young and old ages were immunostained for Bcl-2 oncoprotein. A higher percentage of Bcl-2 immunoreactivity was detected in the adrenal cortical cells of the buffaloes at young ages. The immunoreactivity was moderate in the adrenal cortical cells of the old ages. The degree of intensity was prominent in the zona reticularis than that of the other zones, while negative immunoreactivity in the cells of the adrenal medulla. In conclusion, the immunohistochemical expression of Bcl-2 oncoprotein in the young buffalo’s adrenal gland (antiapoptotic gene) was prominent than the old ages. So the incidence of apoptosis was prominent in the adrenal gland cortical cells of the old age than that the adrenal gland cortical cells of the young ages.

P32 Expression of BCL-2 oncoprotein in women of reproductive age with uterine smooth-muscle tumours in Pakistan

P32 Expression of BCL-2 oncoprotein in women of reproductive age with uterine smooth-muscle tumours in Pakistan

Impact of MTHFR gene C677T polymorphism on Bcl-2 gene methylation and protein expression in colorectal cancer

Objective. To investigate the impact of MTHFR C677T polymorphism on Bcl-2 gene promoter CpG island (CGI) methylation and Bcl-2 protein expression. Material and methods. MTHFR polymorphisms of 86 sporadic colorectal cancer (CRC) patients and 100 healthy volunteers were analyzed by PCR-based restriction fragment length polymorphism, and Bcl-2 promoter CGI methylation in 86 CRC tissues and 86 paired nonneoplastic adjacent tissues was determined by methylation-specific PCR. Bcl-2 oncoprotein expression in 70 CRC tissues and paired nonneoplastic adjacent tissues was detected by immunohistochemistry. Results. The frequency of MTHFR 677 T allele and combined variant genotypes (677CT + TT) in CRC patients was significantly higher than that in healthy controls (p = 0.023 and p = 0.035, respectively), and there is a significant association between 677TT or 677(CT + TT) genotypes and CRC (OR = 2.534, p = 0.045 and OR = 1.888, p = 0.035, respectively). The frequency of methylated Bcl-2 promoter CGI in tumor tissues was significantly lower than that in nonneoplastic adjacent tissues (p = 0.014). The frequency of methylated Bcl-2 promoter CGI in CRC tissues of the individuals with CC genotype was significantly higher than that of those with CT/TT genotypes (p = 0.018), there was significant distribution difference of C and T alleles between individuals with methylated and unmethylated Bcl-2 promoter CGI in colorectal cancer tissues (p = 0.023). Bcl-2 promoter hypomethylation was significantly correlated with Bcl-2 oncoprotein expression in colorectal cancer tissues (r = 0.558, p < 0.001). Conclusion. Bcl-2 promoter is hypomethylated in colorectal cancer tissue, and there is a significant correlation between MTHFR 677 TT or CT/TT genotypes and CRC or Bcl-2 promoter CGI methylation/oncoprotein expression in CRC.

Correlation of cell cycle regulatory proteins (p53 and p16ink4a) and bcl-2 oncoprotein with mitotic index and thickness of primary cutaneous malignant melanoma

The purpose of the study was to determine the frequency of expression p53 and p16INK4a proteins and bcl-2 oncoprotein in malignant skin melanoma and to determine their correlation with the proliferative index and tumor thickness. The study involved 53 patients: 27 (51%) male and 26 (49%) female. Mitotic index showed a correlation with p53 protein expression, a negative correlation with p16INK4a protein expression. Statistically significant correlations were determined between the Breslow tumor thickness, Clark invasion level and p53 protein expression, as well as Breslow tumor thickness and bcl-2 oncoprotein expression (p<0.05), whereas there was no correlation between the p16INK4a protein expression and melanoma thicknes and Clark invasion level. Overexpression p53 protein and bcl-2 oncoprotein, with the loss p16INK4a protein of expression in the nodular melanoma, confirms a frequent loss of function of these tumor suppressor gene and oncogene, and indicates a vertical tumor growth phase. The loss of tumor suppression function the p53 protein and bcl-2 oncoprotein overexpression in cutaneous melanoma correlates with larger tumor thickness, whereas the overexpression of mutated p53 protein and loss p16INK4a protein of expression indicate a higher proliferative tumour potential. Therefore, these evaluated proteins may be the aggressive biological tumour activity markers.

Bcl-2 oncoprotein expression in breast cancer, its relation to estrogen and progesterone receptors and other prognostic factors

Aims of the study: To evaluate the expression of the Bcl-2 oncoprotein in patients with primary breast cancer, to correlate it with estrogen and progesterone receptors and various prognostic parameters.Patients and methods: Fifty two cases of primary breast cancer in which the estrogen and progesterone receptors statuses were previously tested by immuno-histochemical staining, were included in this retrospective study. The cases were collected from Al- Jamhori Teaching Hospital, Nineveh Private Hospital and Private laboratories. The expression of Bcl-2 oncoprotein was evaluated immunohistochemically; the findings were correlated with the estrogen and progesterone receptors, the age of the patients, size, type and grade of the tumor, lymph node status and vascular invasion.Results: Bcl-2 oncoprotein was detected in 24 cases of primary breast cancer (46.2%). In this study the majority of estrogen and progesterone receptors positive cases, (87.5%) and (83.3%) respectively, showed positive Bcl-2 oncoprotein expression, (P

Adrenomedullin, Bcl‐2 and microvessel density in normal, hyperplastic and neoplastic endometrium

Adrenomedullin (ADM) is a multifunctional 52-amino acid peptide involved in numerous physiological and pathological processes, including angiogenesis, growth regulation, differentiation, and vasodilation. ADM is thought to act through the G protein-coupled receptor calcitonin receptor-like receptor, with specificity being conferred by receptor-associated modifying protein 2. The aim of the present study was to clarify the roles of ADM status, and tumor vessels in endometrium. Specimens were examined for ADM, microvessel density (MVD), area of venules (AV) and Bcl-2 oncoprotein using an immunoperoxidase method. The difference of ADM between normal proliferative phase and hyperplasia without atypia was significant (P < 0.05). The level of Bcl-2 was significantly different between hyperplasia without atypia and hyperplasia with atypia (P < 0.05). ADM, MVD and AV in the endometrium increased in a stepwise manner from normal, simple or complex hyperplasia with or without atypia to grade 1 adenocarcinoma. In contrast, expression of Bcl-2 oncoprotein was decreased. These parameters identify the role of ADM expression and Bcl-2 protein in relation to cell growth and vasodilating in the neoplastic changes.

The Calcium Sensing Receptor: From Understanding Parathyroid Calcium Homeostasis to Bone Metastases

The cloning of the calcium sensing receptor (CaR) confirmed that parathyroid cells monitor extracellular calcium concentration ([Ca2+]ext) via a receptor-type mechanism. This lead to the hypothesis that abnormalities in the expression and/or function of the CaR could explain the biochemical abnormalities in primary hyperparathyroidism (PHPT). Cultured cells from parathyroid adenomas of patients operated for PHPT were used to monitor real-time changes in intracellular calcium concentration ([Ca2+]i) as measured by fluorescent microscopy using the Fura-2/AM dye. We found that CaR agonists trigger release of intracellular calcium pools and such responses are amplified by increasing the affinity of IP3 receptors. Using confocal microscopy to monitor membrane trafficking in living parathyroid cells labelled with the fluorescent dye FM1-43, we found that a decrease in [Ca2+]i rather than an absolute change in [Ca2+]ext is the main stimulus for exocytosis from human parathyroid cells. These data suggest that, in PHPT, a defective signalling mechanism from the CaR allows cells from parathyroid adenomas to maintain low [Ca2+]i with uninhibited PTH secretion in the face of hypercalcaemia. Over longer periods of time, CaR controls parathyroid proliferation via changes in tyrosine phosphorylation. We found that multiple proteins of molecular weight 20-65 kDa are phosphorylated within 10-60 min in response to CaR agonists. Further work demonstrated that high [Ca2+]i stimulates the expression of bcl-2 oncoprotein in cultured human parathyroid cells and that, in parathyroid adenomas, predominant expression of bcl-2 rather than bax oncoprotein might prevent apoptosis and explain the slow growth rate of these tumours. More recently, it became apparent that CaR stimulates cell proliferation in several cell types not involved in calcium homeostasis. Using archived histological material from 65 patients who died with metastatic breast cancer, we identified CaR expression predominantly in tumours from patients who developed bone rather than visceral metastases (35 of 49 versus 7 of 16; P < 0.01, chi-squared test). These data suggest that CaR expression has the potential to become a new biological marker predicting the risk of bone metastases in patients with breast cancer. A prospective study should investigate if patients with CaR-positive tumours are more likely to develop bone metastases and whether they could benefit more from prophylactic treatment with bisphosphonates or the newly developed CaR antagonists.

Primary Neuroendocrine Carcinoma of the Vagina With Merkel Cell Carcinoma Phenotype

We describe a case of primary neuroendocrine carcinoma arising from the anterior vaginal wall of a 67-year-old woman. Primary neuroendocrine carcinoma of the vagina is a rare entity with only 25 previously reported cases in the literature. In previous reports, these tumors have not been distinguished from primary neuroendocrine carcinoma of the skin (Merkel cell carcinoma). The tumor was composed of cells that showed neuroendocrine-type nuclear features with hyperchromasia, nuclear molding, occasional small nucleoli, and a chromatin pattern that was finely granular. The tumor cells were positive for cytokeratin 20 (CK20), neuron specific enolase, pancytokeratin, epithelial membrane antigen, and chromogranin A expression. Ki-67, a marker of proliferation, was also positive in>90% of cells. The tumor cells showed intense expression of Bcl-2 oncoprotein and mild to moderate expression of c-KIT. Synaptophysin, neurofilament, CD45, CD56, CD10, S-100, HMB-45, cytokeratin 7, and thyroid transcription factor 1 were negative. This pattern of staining is consistent with a Merkel cell carcinoma. This is the first report of a primary neuroendocrine carcinoma of the vagina with a Merkel cell phenotype. Previous studies have not distinguished primary neuroendocrine carcinoma of the vagina from Merkel cell carcinoma of the skin. Positive expression of CK20 in primary small cell carcinoma of the vagina might represent a Merkel cell carcinoma subtype of this tumor.

Proliferative Activity, Apoptosis and Expression of Oestrogen Receptor and Bcl-2 Oncoprotein in Canine Mammary Gland Tumours

Samples of 39 canine mammary gland tumours (MGTs) were examined immunohistochemically for oestrogen receptor (ER-alpha), Bcl-2 protein and Ki67 antigen, and by TUNEL assay for apoptosis. ER-alpha was expressed by 80% (31/39) of the tumours, including all of the 15 benign tumours and 67% (16/42) of the malignant tumours. ER-alpha expression was greater in the benign than in the malignant tumours (P<0.01). Bcl-2 protein was detected in 62% (24/39) of the MGTs, of which 67% (10/15) were benign and 58% (14/24) malignant. No significant difference in Bcl-2 expression between benign and malignant tumours was detected. The Ki67 and TUNEL indices were greater in malignant than in benign tumours (P<0.01). Correlation analysis suggested that ER-alpha and Bcl-2 expression were related, but this observation lacked statistical significance. The levels of cell proliferation and apoptosis did not appear to be significantly correlated with the expression of Bcl-2. A positive relationship was apparent between cell proliferation and apoptosis, whilst a negative correlation between ER-alpha and cell proliferation was demonstrated. In conclusion, the suggestion of a positive correlation between ER-alpha and Bcl-2 in canine MGTs indicates that ER may be the regulator of Bcl-2 protein, as in human breast cancer. In contrast to cell proliferation and apoptosis, ER-alpha and Bcl-2 expression were greater in benign MGTs than in their malignant counterparts.

P53 and bcl-2 Expression in Invasive and Pre-invasive Uterine Papillary Serous Carcinoma and Atrophic Endometrium

Introduction: Uterine papillary serous carcinoma (UPSC), a high-grade tumour, is known to be associated in some cases with an identifiable intraepithelial neoplasia (IEN) component. Biomarker studies incorporating this latter component are not well documented. One aim of the present study was to compare levels of immunohistochemical (IHC) expression of p53 tumour suppressor gene and bcl-2 oncoprotein between UPSC and IEN, as well as normal endometrium to determine its biologic significance. The other major aim was to determine if these IHC results have any bearing on survival data in this tumour. Materials and Methods: An immunoreactivity score was assigned for examination of p53 and bcl-2 expression in a total of 21 cases of UPSC, 9 with an evaluable IEN component and 11 with associated non-neoplastic endometrium. Statistical analysis of IHC results was performed, in addition to correlation with survival data and disease stage. Results: p53 was identified in 16/21 cases of UPSC (76%) and 8/9 cases of IEN (89%), and no cases of normal endometrium. By contrast, bcl-2 was positive in all normal endometria with less expression in UPSC leaving 15/21 (71%) cases positive, and in IEN, leaving 5/9 (55%) of cases positive. Differences in immunoreactive scores for both p53 and bcl-2 between UPSC and benign glands, as well as between IEN and benign glands reached statistical significance with P values of 0.006 and 0.014 for p53, and 0.003 and 0.027 for bcl-2 respectively. There was no statistical significance between values for UPSC and IEN. Cox regression analysis found no statistically significant relationship between patient survival time in early and late stages of disease, and p53 and bcl-2 immunoscores. Conclusions: The lack of a significant difference between the bcl-2 and p53 values for both UPSC and IEN suggests that these molecular alterations occur at an early stage of tumour pathogenesis. A potential advantage of the use of immunohistochemical markers is their application to routinely processed surgical specimens. In this case, bcl-2 and p53 were applied in UPSC to determine any potential significance, but neither marker proved to be a useful predictor of survival time or disease stage.

Low frequency of bcl-2 expression in large non-polypoid colonic neoplasms.

Large non-polypoid colorectal adenomas that spread over the mucosa and morphologically flat lesions are included in a group called granule-aggregating tumours. These are uncommon in the West. We aimed to clarify the biological differences between granule-aggregating tumours and colorectal polypoid adenomas. We evaluated the extent of apoptotic cell loss and expression of bcl-2 and p53 oncoproteins in 26 granule-aggregating tumours and 19 polypoid adenomas. The mean apoptosis index value of granule-aggregating tumours was significantly higher than that of polypoid adenomas. Only two (7.7%) granule-aggregating tumours and 13 (68.4%) polypoid colorectal adenomas expressed bcl-2, while 12 (46.2%) granule-aggregating tumours and six (31.6%) polypoid colorectal adenomas were p53-positive. Our results show that the higher apoptosis index and frequent expression of bcl-2 oncoprotein differentiates granule-aggregating tumours from polypoid colorectal adenomas. We propose that large non-polypoid granule-aggregating tumours of the colorectum are a biologically distinct entity.

Acetone extract of Angelica sinensis inhibits proliferation of human cancer cells via inducing cell cycle arrest and apoptosis

Angelica sinensis (Oliv.) Diels, a traditional Chinese medicine, has been widely prescribed in treatment of gynecological diseases. Bio-based assays for extracts of Angelica sinensis showed that the acetone extract (AE-AS) had dose-dependently antiproliferative effect on A549, HT29, DBTRG-05MG and J5 human cancer cells. The IC 50 values of AE-AS on mentioned cancer cells ranged from 35 to 50 μg/ml after 24 h of treatment. After 72 h of exposure, AE-AS (40 μg/ml) significantly reduced A549 cell proliferation to 24 ± 3.2% of control. In A549 cells, the cell cycle analysis showed that AE-AS induced a significant increase in the number of cells in G0/G1, with a concomitant decrease in the number of cells in S phase. AE-AS-induced chromatin changes and apoptosis of A549 cells were confirmed by Hoechst 33342 DNA staining and annexin V staining. A549 cells treated with AE-AS caused activation of caspase-9 and -3, and AE-AS-induced apoptosis could be inhibited by the broad-spectrum caspase inhibitor, z-VAD-fmk. The Western blot indicated the AE-AS-triggered apoptosis is mediated via suppression of Bcl-2 oncoprotein expression rather than p53 or Bax. Besides, AE-AS decreased the levels of cdk4 protein was observed. These results indicate that the AE-AS could induce G1/S arrest and activate the mechanism of apoptosis in human cancer cells. Extracts obtained from different methods of fractionation might possess distinct bioactivity. These results prompted us to further evaluate the in vivo anticancer effects and elucidate the chemical composition profile of AE-AS.