Ki-67 expression in primary breast carcinomas and their axillary lymph node metastases: clinical implications

Proliferative activity of tumour cells assessed by immunohistochemical Ki-67 expression is one of several prognostic indicators in breast cancer. The major objective of this study was to investigate the prognostic impact of Ki-67 proliferative activity in the axillary lymph node metastases and in the matched primary breast carcinoma from 194 patients. There was a statistically significant up-regulation of Ki-67 protein in the metastatic deposit compared to where the primary tumour was found (p = 0.001). A low Ki-67 index in both the primary and the metastatic tumours was a favorable prognostic factor. A high index in both primary and metastatic lesion and an up-regulation from a low index in the primary tumour to a high index in the metastatic deposit represented an unfavorable prognostic factor. Multivariate analysis showed that Ki-67 expression in the metastases was a superior independent prognostic factor of clinical outcomes compared to that in the primary tumours. Ki-67 expression in ≥10% of carcinoma cells in the primary tumours and ≥15% in the nodal metastases seems to be optimal cut-off levels. Ki-67 is of value as an independent prognostic factor in breast cancer.     

CK20 and Ki-67 as significant prognostic factors in human bladder carcinoma

Aberrant expression of CK20 and Ki-67 has been documented in many kinds of primary tumors and has proved useful as an ancillary diagnostic aid for those tumors. The aim of this study was to analyze the expression patterns of CK20 and Ki-67 in human bladder carcinomas (BCa) and to evaluate their clinical significance in the progression of BCa. CK20 and Ki-67 expression in BCa and normal bladder tissues were detected by immunohistochemical staining. The Spearman correlation was calculated between the expression of CK20 and Ki-67 in BCa tissues. The correlation of CK20 and Ki-67 expression with the clinicopathological characteristics and the prognosis of BCa were subsequently assessed. CK20 expression was positively expressed in 103/154 (66.9%) of BCa and 2/30 (6.67%) of normal bladder tissues, respectively. The positive expression rate of Ki-67 in BCa tissues was also significantly higher than those in normal bladder tissues (81.8 vs. 10%, p < 0.01). The Spearman analysis indicated that the expression level of CK20 has a significant positive correlation with that of Ki-67 (rs = 0.86, p = 0.02). Pathologic findings demonstrated that the intensity of CK20 and Ki-67 staining in cancerous tissues was associated significantly with tumor grades (p = 0.03, p < 0.01), distant metastasis (both p < 0.01) and TNM grades (p = 0.01, p = 0.03) of BCa. The progression-free survival of the patients with CK20 (+)/Ki-67 (+) expression was poorest (p < 0.01). The results suggest that the expression of CK20 and Ki-67 may be an important feature of BCa, and the detection of their co-expression may benefit the prediction of BCa prognosis.     

Clinicopathological and prognostic significance of p53, Ki-67, and Bcl-2 expression in Tunisian gastric adenocarcinomas

Gastric carcinoma (GC) is a highly aggressive malignancy with poor prognosis. It is widely accepted that malignancy results from abnormal cell growth due to dysregulation of the balance between cell proliferation and apoptosis. Our study aimed to investigate the clinicopathological and prognostic significance of p53, Ki-67, and Bcl-2 in Tunisian GC patients by immunohistochemistry. It was observed that the older patients showed p53 overexpression compared with the younger patients (p < 0.05). There was higher p53 expression in the intestinal-type compared with the diffuse-type (p < 0.05), and in well/moderate differentiated than in poor differentiated tumors. The expression of Ki-67 was positively associated with tumor size and venous invasion (p < 0.05). Bcl2 expression occurred in male patients and correlated with depth of invasion (p = 0.02). A Kaplan–Meier analysis indicated an inverse correlation between p53 and Ki-67 expression and the overall survival. Multivariate analysis revealed that the tumor site, Ki-67 and p53 expression were independent prognostic factors for gastric carcinomas (p < 0.05). Finally, combined expression of p53, Ki-67 and Bcl-2 showed that the group of patients with tumors p53+/Ki-67+/Bcl2− had aggressive behavior and poor prognosis (p log rank = 0.000). In summary, our data indicated that the expression of p53, Ki-67, and Bcl-2 may provide useful information for identifying patients with aggressive behavior and poor prognosis of GC.     

Elevated hepatocyte paraffin 1 and neprilysin expression in hepatocellular carcinoma are correlated with longer survival

Hepatocyte paraffin 1 (Hep Par 1) and neprilysin (CD10) are well-known markers of hepatocellular carcinoma (HCC). To assess their potential prognostic role, we conducted a retrospective analysis of 97 formalin-fixed and paraffin-embedded HCC from patients treated by surgery with curative intent, using standard immunohistochemical procedures and semiquantitative analysis. Strong Hep Par 1 expression and canalicular CD10 staining pattern were significantly correlated with smaller tumor size (p=0.007 and 0.04, respectively). On univariate analysis, longer overall survival was observed in patients with strong Hep Par 1 expression (p=0.0005) and in patients with a CD10can staining pattern (p=0.02). On multivariate analysis, the combined immunohistochemical score (CIS) obtained by addition of Hep Par 1 and CD10can scores and subtraction of cytoplasmic CD10 score was retained as the single most important prognostic factor (p=0.001). Patients with a CIS <4 had a 3.5-fold increased risk of death, as compared to those with a CIS ≥4. In conclusion, strong Hep Par 1 expression, presence of CD10can labeling, and absence of CD10cyt staining are favorable prognostic factors in HCC, which can be easily combined into a single immunohistochemical score for routine clinical use.     

Determination of Cell Proliferation Using Mcm2 Antigen and Evaluation of Apoptosis and TGF-β1 Expression in GH-secreting or Clinically Nonfunctioning Pituitary Adenomas

Pituitary adenomas (PA) occasionally show aggressive behavior, with invasion of the surrounding tissues. The identification of markers able to recognize aggressive PA in early stages remains a challenge. We aimed to determine the expression of a new cell proliferation marker, Mcm2, and the presence of apoptosis in PA, and to evaluate the association of clinicopathological features with the apoptotic and proliferative indices. Additionally, the TGF-β1 expression, an inducer of apoptosis, was determined. The proliferative index was determined in GH-secreting or clinically nonfunctioning PA using immunohistochemical (IH) methods for Mcm2 and Ki-67 antigens. The apoptosis was assessed by the TUNEL method and the TGF-β1 expression by IH. A significant positive correlation was found between log Mcm2 index and log Ki-67 index (p < 0.001). Mcm2 and Ki-67 detected a similar number of proliferating cells. Mcm2 index showed a significant association with tumor extension (p = 0.02), but not with tumor invasion. Apoptosis was detected in 17% of the adenomas, with a maximum apoptotic index of 0.77%. Immunoreactivity to TGF-β1 was observed in 77% of the adenomas, showing an association with tumor extension. We concluded that, in this sample, Mcm2 was similar to Ki-67 in the identification of the proliferating cells and that apoptosis was rare.     

Differential expression of human telomerase catalytic subunit mRNA by In situ hybridization in pheochromocytomas

In pheochromocytomas, it is very difficult to predict malignant potential by conventional histology or immunohistochemical and molecular markers. We investigated the expression of human telomerase catalytic component (hTERT) mRNA, hTERT protein, Ki-67 antigen, and p27^kip1 in pheochromocytomas (27 benign, 7 suspected malignant, and 7 malignant), and evaluated the possibility of expressions of these proteins, and hTERT mRNA serve as diagnostic markers for predicting the biological behavior of these tumors. All tumors showed the classical histology and typical immunohistochemical pattern. By in situ hybridization, hTERT mRNA was expressed in 5/7 malignant tumors (defined as the presence of metastasis and/or extensive local invasion) as compared with 3/27 benign tumors. We examined the hTERT by immunohistochemistry to confirm the mRNA. hTERT mRNA expression was correlated with hTERT protein expression. All benign tumors exhibited no immunopositivity or <1% of cells stained for Ki-67 antigen. Six out of seven malignant tumors have shown either hTERT mRNA expression or Ki-67 immunoreactivity While no statistical difference in p27^kip1 expressions was observed among benign, malignant, and suspected malignant tumors, there was a statistical difference between the normal adrenal medulla samples and tumors (p<0.001). Thus, hTERT mRNA detection by in situ hybridization, hTERT expression, and Ki-67 antigen expression are all useful tools for differentiating malignant from benign pheochromocytomas.     

Both c-Myc and Ki-67 expression are predictive markers in patients with Extranodal NK/T-cell lymphoma,nasal type: A retrospective study in China

Extranodal natural killer (NK)/T-cell lymphoma, nasal type (ENKTL) is an increasingly recognized disease entity of aggressive tumor progression. The objective of this study was to investigate the clinical and prognostic significance of c-Myc and Ki-67 expression in ENKTL. Immunohistochemistry for c-Myc and Ki-67 was performed on tissue sections from 53 patients diagnosed with ENKTL, and their correlation with clinicopathologic variables was assessed. We also made a comparison between c-Myc positive and negative ENKTL on proliferation index (PI); and analyzed relationship between expression of c-Myc and Ki-67 index. The survival was analyzed by Kaplan–Meier product-limit method. Positive expression of c-Myc was shown in 64.2% of the patients, and high expression of Ki-67 was found in 66%. The PI in c-Myc-positive tumor cell was significantly higher than that in c-Myc-negative ones (P = 0.005). The positive correlation between c-Myc expression and Ki-67 index was also found (r = 0.454, P = 0.001). Patients of c-Myc expression were shown to be associated with unfavorable overall survival (OS) and decreased progression free survival (PFS) (P = 0.000 and 0.013, respectively). High expression of Ki-67 was also shown to be correlated with worse OS and PFS (P = 0.014 and 0.016, respectively). And patients expression of c-Myc+/Ki-67 high had the worst OS and PFS (P = 0.002 and 0.027, respectively). c-Myc may play an important role in the carcinogenesis of NK/T cell lymphoma by promoting cell proliferation. Both c-Myc expression and Ki-67 high expression in ENKTL patients may be valuable indicators for predicting the survival of ENKTL patients.     

Lung carcinoid tumours: histology and Ki-67, the eternal rivalry

WHO classification of Thoracic Tumours defines lung carcinoid tumours (LCTs) as well-differentiated neuroendocrine neoplasms (NENs) classified in low grade typical (TC) and intermediate grade atypical carcinoids (AC). Limited data exist concerning protein expression and morphologic factors able to predict disease aggressiveness. Though Ki-67 has proved to be a powerful diagnostic and prognostic factor for Gastro-entero-pancreatic NENs, its role in lung NENs is still debated. A retrospective series of 370 LCT from two oncology centers was centrally reviewed. Morphology and immunohistochemical markers (Ki-67, TTF-1, CD44, OTP, SSTR-2A, Ascl1, and p53) were studied and correlated with Overall Survival (OS), Cancer-specific survival (CSS) and Disease-free survival (DFS). Carcinoid histology was confirmed in 355 patients: 297 (83.7%) TC and 58 (16.3%) AC. Ki-67 at 3% was the best value in predicting DFS. Ki-67 ≥ 3% tumours were significantly associated with AC histology, stage III-IV, smoking, vascular invasion, tumour spread through air spaces OTP negativity, and TTF-1, Ascl1 and p53 positivity. After adjustment for center and period of diagnosis, both Ki-67 (≥3 versus <3) and histology (AC versus TC) alone significantly added prognostic information to OS and CSS multivariable model with age, stage and OTP; addition of both variables did not provide further prognostic information. Conversely, an improved significance of the DFS prediction model at multivariate analysis was seen by adding Ki-67 (≥3 versus <3, P adj = 0.01) to TC and AC histological distinction, age, lymph node involvement, residual tumour and OTP. Ki-67 ≥ 3% plays a potentially pivotal role in LCT prognosis, irrespective of histological grade.     

Angiogenic cytokines in mesothelioma: a study of VEGF,FGF-1 and -2, and TGF β expression

Vascular endothelial growth factor (VEGF), acidic and basic fibroblast growth factors (FGF-1 and -2), and transforming growth factor β (TGFβ) are potent angiogenic cytokines. Malignant mesothelioma of the pleura presents with a high intra-tumoural microvascular density (IMD) which also has prognostic relevance. This study was designed to verify the immunohistochemical expression of the angiogenic cytokines in mesothelioma as well as in non-neoplastic human mesothelial cells and to study the individual as well as the combined expression of these cytokines in mesothelioma in relation to both IMD and prognosis. In addition, four mesothelioma cell lines were studied by ELISA for the secretion of VEGF and FGF-2 in their supernatants and were shown to contain high levels of both of these cytokines. Immunohistochemically, VEGF, FGF-1 and -2, and TGFβ immunoreactivity was present in 81, 67, 92 and 96 per cent of mesotheliomas, and in 20, 50, 40, and 10 per cent of samples of the non-neoplastic mesothelium, respectively. Co-ordinate expression of the cytokines was observed whereby mesotheliomas expressed more than one cytokine. The combined immunohistochemical expression levels for all four cytokines correlated significantly with both IMD ( p=0·01) and prognosis ( p=0·0013). When studied individually, high FGF-2 expression correlated best with more tumour aggressiveness and worse prognosis for mesothelioma ( p=0·0011). There was no significant correlation between prognosis and immunoexpression of VEGF ( p=0·07), FGF-1 ( p=0·3), or TGFβ ( p=0·1), or between IMD and any of the cytokines studied individually. These data support the assertion that selective angiogenic cytokines might contribute to the progressive changes of mesothelioma by tumour angiogenesis. Copyright © 1999 John Wiley & Sons, Ltd.     

The prognostic significance of non-lymphoid immune cells of the tumor microenvironment,including neutrophils,eosinophils, and mast cells in breast carcinomas

Background and objectiveThe prognostic importance of lymphoid cells in the tumor microenvironment and their effect on treatment response have been demonstrated in many cancer types. However, there are limited studies on non-lymphoid immune cells. Conflicting results have been obtained regarding the effects of these cells on prognosis.Materials and methodsA total of 331 patients who underwent surgery for breast cancer were included. Patients that received neoadjuvant chemotherapy and those with distant metastasis were excluded. CD 15 immunohistochemistry was performed to detect tumor-infiltrating neutrophils (TINs) and eosinophils (TIEs), while Toluidine Blue histochemistry was performed to detect tumor-infiltrating mast cells (TIMs).ResultsHigh TINs were statistically associated with low ER expression (p < 0.001), low PR expression (p = 0.001), high Ki-67 proliferation index (p = 0.008), and HER2/TN molecular subtypes (p = 0.001). High TIEs were associated with low ER expression (p = 0.001), high Ki67 proliferation index (p = 0.005), and HER2/TN molecular subtype (p = 0.002). High TIMs were associated with high PR expression (p = 0.024), low Ki-67 proliferation index (p = 0.003), and high survival rate (p = 0.006). TIMs and TIEs were good prognostic factors for overall survival in Luminal A and Luminal B subtypes, while TINs and TIEs were found to be independent risk factors for disease-free survival.ConclusionThe evaluation of components of the tumor microenvironment including TINs, TIEs, and TIMs is easy and practical. High TIMs and TIEs are independent prognostic factors, especially in luminal molecular subtype of invasive breast carcinoma. However, to use this parameter in routine pathology practice, more studies from different centers and standard evaluation are needed.     

Expression of E-cadherin,b-catenin,and Ki-67 in goblet cell carcinoids of the appendix: an immunohistochemical study with clinical correlation

Goblet cell carcinoid (GCC) of the appendix is a rare entity, of which both the histogenesis and biologic behavior remain controversial, and prognostic tools and therapeutic strategies for this unusual tumor have yet to be defined. The aim of this study was to analyze expression of E-cadherin and β-catenin in GCCs of the appendix with long-term follow-up data as related to the expression of Ki-67 proliferation marker to provide a rationale for treatment guidelines. We analyzed the expression of E-cadherin, β-catenin, and Ki-67 in 11 GCCs of the appendix and control groups of typical carcinoids of the large intestine (n=29), well to moderately differentiated adenocarcinomas of the colon (n=10), poorly differentiated adenocarcinomas of the colon (n=12), and normal appendiceal tissues (n=10). There was no significant difference between the GCCs and normal appendiceal tissues regarding the expression of E-cadherin or β-catenin (p=0.297 and 0.103, respectively). The percentage of positive GCC cells ranged between 0.52 and 10.35% (4.27 ± 0.80), and only one case had a score > 10%. Metastatic tumor spread and death were found in high MIB-1 labeling index (LI) cases of GCC (>3%). Our findings suggest that the behavior of the majority of GCCs might be indolent and different from adenocarcinomas because of the preserved expression of E-cadherin and β-catenin and relatively low MIB-1 LI. However, some of these tumors act aggressively and MIB-1 LI might be a good parameter to determine the therapeutic procedure.     

Cyclin D1 expression in astrocytomas is associated with cell proliferation activity and patient prognosis

An important positive regulator of the cell cycle, cyclin D1, is often amplified and overexpressed in malignancies. Cyclin D1 aberrations were analysed in grade II–IV astrocytomas by fluorescence in situ hybridization (FISH), mRNA in situ hybridization and immunohistochemistry. Proliferation activity was determined by Ki-67^MIB-1 immunolabelling and mitotic counting. High cyclin D1 expression was observed in grade IV astrocytomas (grades II–III versus grade IV; mRNA expression: p < 0·001; immunoexpression: p = 0·013), and correlated with poor patient survival (p < 0·001, n = 46). Upregulated cyclin D1 expression was also closely associated with poor patient prognosis in grade II–III astrocytomas (p < 0·001, n = 30). Cyclin D1 gene was not found to be amplified (n = 7). Cell proliferation activity was significantly increased in tumours exhibiting high cyclin D1 mRNA levels (Ki-67^MIB-1: p < 0·001; mitotic count: p < 0·001) and high cyclin D1 protein expression (Ki-67^MIB-1: p = 0·002; mitotic count: p = 0·012). These results indicate that increased production of cyclin D1 is closely associated with high cell proliferation activity and aggressive behaviour in diffusely infiltrating astrocytomas. Copyright © 1999 John Wiley & Sons, Ltd.     

Immunohistochemical analyses of β-catenin and cyclin D1 expression in giant cell tumor of bone (GCTB): A possible role of Wnt pathway in GCTB tumorigenesis

Giant cell tumor of bone (GCTB) is a benign neoplasm but occasionally shows local recurrence, and histologically consists of osteoclast-like giant cells (GC) and stromal mononuclear cells (SC), which are capable of proliferation and osteoblastic differentiation. Activation of Wnt signaling can induce osteoblast differentiation and osteoclastgenesis during bone resorption process. This study analyzed the profiles of β-catenin and cyclin D1 expression in GCTB to elucidate an involvement of Wnt pathway in tumorigenesis. We performed immunohistochemistry for β-catenin, cyclin D1, and Ki-67 in 16 GCTB tumors, including 5 recurrent cases that were surgically resected. All 16 cases of GCTB displayed β-catenin, cyclin D1, and Ki-67 expression. Immunoreactivity for β-catenin was observed in nuclei of SC and GC. Cyclin D1 immunoreactivity was found mainly in nuclei of GC, while Ki-67 immunoreactivity was restricted to nuclei of SC. The nuclear β-catenin labeling index (LI) in both SC (60.6 vs. 41.8%, p=0.074) and GC (41.7 vs. 20.1%, p=0.095) was higher in recurrent tumors than in primary tumors in all the 4 cases. However, Ki-67 LI in SC (18.8 vs. 19.9%, p=0.851) and cyclin D1 LI in GC (55.4 vs. 70.1%, p=0.225) were not higher in recurrent tumors than in primary tumors. Our results suggested activation of Wnt/ β-catenin pathway in GCTB tumorigenesis. Since cyclin D1 in GC was never associated with the expression of the well-known proliferative marker Ki-67, cyclin D1 expression might play a role in GC formation instead of promoting cell proliferation during GCTB tumorigenesis. Importantly, it was suggested that the nuclear β-catenin staining level might be associated with tumor recurrence in GCTB.     

Cell-cycle analysis detecting endogenous nuclear antigens: Comparison with BrdU-in vivo labeling and an application to lung tumors

The versatility of non-radioactive cell-cycle analysis in detecting endogenous nuclear antigens of the proliferating cells was evaluated. Optimal conditions for immunostaining varied in fixation and pretreatment procedures among antigens, bromodeoxyuridine (BrdU), Ki-67 epitope, DNA polymerase α and PCNA. A significant correlation between BrdU labeling index (LI) was observed in each positive ratio (PR, positive/total neoplastic cells) for nuclear antigens in tumor-sections which had been labeled in vivo with BrdU. The best correlation was observed in Ki-67 PR (y = 1.26x+ 2.5; y= Ki-67 PR; x= BrdU LI; r= 0.97). To determine its prognostic value, Ki-67 analysis was applied to the surgically resected lung tumors. Ki-67 PR were different according to the histologic types of the tumors: 47.8 ± 3.4% in small cell carcinoma; 29.5 ± 3.5% in squamous cell carcinoma; 28.3 ± 4.7% in large cell carcinoma; 15.2 ± 1.8% in adenocarcinoma and 0.1 ± 0.1% in mature carcinoid tumor. When the mean value was used to divide each type to a higher or lower proliferative activity (15% Ki-67 PR for adenocarcinoma and 30% for squamous cell carcinoma), the group with the lower Ki-67 PR showed a significantly more favorable prognosis than that of a higher ratio. Ki-67 PR was not correlated with other pathologic factors such as size, lymph node metastasis or pleural involvement. Non-radioactive cell-cycle analysis was feasible and useful for detecting endogenous nuclear antigens even in the lung tumors, particularly when the analysis was coupled with histologic typing.     

High-affinity monomeric 67-kd laminin receptors and prognosis in pancreatic endocrine tumours

Cell-surface high-affinity monomeric 67-kD laminin receptors have been proposed to promote the invasion and metastasis of a variety of tumours, but there are, as yet, no data regarding the expression of these molecules in pancreatic endocrine tumours (PETs). The prognosis of these very rare tumours is problematic and the only irrefutable evidence of their malignancy still continues to be the occurrence of local invasion and metastases. In this retrospective investigation, 34 functioning and 48 non-functioning sporadic PETs were evaluated for the expression of the MLuC5 monoclonal antibody, which specifically recognizes the 67-kD laminin receptors. Laminin receptors were found in 42/82 cases (51 per cent) and their expression was associated with metastatic disease (P<0·001), high proliferative activity expressed by a Ki-67 index above 5·0 per cent (P<0·001), absence of progesterone receptors (P=0·013), immunoreactivity for hormones other than insulin (P<0·001), a tumour diameter more than 3·0 cm (P=0·001), and a fatal clinical outcome (P<0·001). Laminin receptors were also expressed by most metastatic foci and all intravascular emboli of tumour cells. Positivity for laminin receptors was associated with shorter survival in functioning (P=0·026) and non-functioning (P=0·042) tumours, as well as in the whole series of pancreatic endocrine tumours (P<0·001). On multivariate analysis, laminin receptor expression was not an independent prognostic factor, while a Ki-67 index above 5·0 per cent was the most powerful predictor of survival. However, the association of laminin receptor expression and Ki-67 index could identify a group of malignant PETs with low proliferative activity characterized by an intermediate prognosis. In conclusion, these data suggest that monomeric laminin receptors may play a role in the invasion and metastasis of PETs and that their expression may be an additional prognostic factor, along with proliferative activity. © 1997 by John Wiley & Sons, Ltd.     

Expression of the receptor for parathyroid hormone-related protein in normal and malignant breast tissue

Parathyroid hormone-related protein (PTHrP) is the cause of humoral hypercalcaemia of malignancy and interacts with parathyroid hormone (PTH) receptors. Breast cancer cells produce PTHrP in vitro and in vivo. The breast cancer cell line MCF-7, which products PTHrP and expresses PTHrP receptors, proliferates in response to PTHrP. The aim of these studies was to determine the tissue location of PTHrP/PTH receptors (PTHrPR) in primary breast carcinomas and to establish whether they had the potential to respond to PTHrP. The cellular location of mRNA for the PTHrP/PTH receptor was identified using in situ hybridization in primary breast carcinomas and normal breast tissue. Immunohistochemistry for PTHrP was carried out on the same specimens. Tumours were assessed and scored by two observers using the product of intensity of signal and number of positive tumour cells (possible range 0–9). Tumours were also assessed for Ki-67 expression by counting positive nuclei. Non-malignant ductular epithelium expressed mRNA for the PTHrP receptor (mean score 2·6, range 1–4). Breast carcinomas (mean score 4·4, range 0–9) showed variable expression of PTHrP receptor mRNA: eight tumours were negative, 50 had scores similar to normal breast tissue, and 49 had higher scores for the receptor. Levels of expression of the receptor within the primary breast carcinomas were unrelated to immunohistochemical detection of PTHrP or to any standard prognostic factor. There was a significant (P=0·05) relationship between Ki-67 and PTHrPR expression in individual tumours. The presence of PTHrP and its receptor in normal breast epithelium and breast carcinomas demonstrates that most breast tumours are able to respond to PTHrP. The Ki-67 data suggest that PTHrP is a potential autocrine growth factor in primary breast carcinoma. © 1997 John Wiley & Sons, Ltd.     

Increased proliferative activity and p53 expression in normal glandular breast tissue after radiation therapy

Radiation used in breast-conserving therapy (BCT) for early breast cancer, to eradicate residual malignant cells after tumour resection, induces DNA damage and cell death. Little is known about the effect of the commonly used doses of radiation therapy on normal breast tissue. Under physiological conditions, p53 plays a role in maintaining genomic stability and regulating progression through the cell cycle. In normal glandular breast tissue, p53 expression is very low, as is proliferative activity. The purpose of this study was to investigate the levels of p53 expression and proliferative activity in non-malignant glandular epithelium of the breast after BCT. The immunohistochemical expression of p53 and Ki-67 was semiquantitatively correlated in non-malignant glandular epithelium in biopsies before and after BCT in 24 women with breast cancer. In 18 cases, a recurrence was diagnosed and in the remaining cases, the clinical suspicion was not histologically confirmed. In addition, in six cases with contralateral breast cancer, the same immunohistochemical evaluation was performed in tissue from both breasts. The mean interval between the two surgical interventions was 50 months. The percentage of p53 immunoreactive epithelial cells in normal breast tissue was significantly (P<0·01) higher after radiation therapy than before in the ipsilateral side (0·2 per cent±0·3 and 4·6 per cent ±4·5, respectively). Ki-67 immunoreactivity was also significantly increased (P<0·001) after radiation therapy, from 0·6 per cent to an average of 4·8 per cent in epithelial cells. In contrast, in the patients with contralateral breast cancer, the levels of p53 and Ki-67 immunoreactivity in the normal glandular breast tissue were comparable to the ipsilateral side (P=0·7 and P=0·1, respectively). In conclusion, increased expression of p53 and Ki-67 is present in normal glandular breast tissue, even 2–5 years after radiation therapy. © 1998 John Wiley & Sons, Ltd.     

Expression level of the mitotic checkpoint protein and G2–M cell cycle regulators and prognosis in gastrointestinal stromal tumors in the stomach

The biological behavior of gastrointestinal stromal tumors (GISTs) ranges from benign to malignant, and the risk of an adverse outcome is correlated with the location of the primary tumor, tumor size, and mitotic counts. Cell cycle regulators are potentially associated with the tumorigenesis and progression of GISTs. Checkpoint with forkhead and ring finger (CHFR) functions as an important checkpoint protein in the early to mid-prophase to regulate mitosis. In this study, we evaluated the expression of CHFR and several cell cycle regulators, including cyclin A, cyclin B1, cdc2, and cdk2, by immunohistochemical staining in 53 cases of primary gastric GISTs, and compared the immunohistochemical results with the clinicopathological factors or the GIST risk grades as modified by Miettinen et al. Of the 53 cases, 18 (34%) showed decreased nuclear CHFR expression. Decreased CHFR expression was correlated with higher mitotic counts [>5/50 high-power fields (HPFs)] (p = 0.039) and a high-risk grade (p = 0.0475), but not with expression of other cell cycle regulators. Higher cyclin A labeling index (LI, >1.5%), cyclin B1 LI (>0.25%), cdc2 LI (>1.16%), Ki-67 LI (>4.9%), mitotic counts (>5/50 HPF) and high-risk grade were each associated with shorter disease-free survival (p = 0.0017, p = 0.003, p = 0.0471, p = 0.002, p < 0.001, and p = 0.0017, respectively). Our results suggest that modified risk grade and increased expression of G2–M regulators such as cyclin A, cyclin B1, and cdc2 are useful for predicting the biological behavior of gastric GISTs. In addition, decreased CHFR expression may play a role in increased proliferative activity of higher grade GISTs.     

Mitochondrial UCP4 and bcl-2 expression in imprints of breast carcinomas: relationship with DNA ploidy and classical prognostic factors

Mitochondria are the bioenergetic and metabolic centers of cells and play an important role in the regulation of cell death. The mitochondrial apoptosis pathway is controlled by the bcl-2 protein family. Overexpression of mitochondrial uncoupling protein 4 (UCP4) can promote proliferation and inhibit apoptosis and differentiation. Imprint smears obtained from 124 tumors were studied immunocytochemically, and results were correlated with prognostic markers. There were 112 ductal and 12 lobular carcinomas. The positivity of UCP4 was correlated with lymph node metastases (p = 0.005), positive ER and PR expression (p < 0.0001 for both), as well as positivity for p53 (p < 0.0001) and Ki-67 (p < 0.0001). Decreased expression of bcl-2 correlated with increased expression of UCP4 (p = 0.001). Regarding DNA ploidy, UCP4 positivity was correlated with aneuploid tumors (p = 0.002). Negative expression of bcl-2 was correlated with poorly differentiated carcinomas (p < 0.0001), as well as with positive expression of p53 (p < 0.0001) and Ki-67 (p < 0.0001). Logistic regression revealed that ploidy and p53 expression had an impact on UCP4. These findings encourage future investigations regarding the potential role of UCPs not only into mechanisms underlying breast cancer, but also as a novel candidate to the design and development of more effective therapeutic strategies.