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P Hirvikoski

Publications and source records attributed to P Hirvikoski.

At least 19 recordsLinked to original sources
PubMed2007

Expression profiling of PC-3 cell line variants and comparison of MIC-1 transcript levels in benign and malignant prostate.

BACKGROUND: The mechanisms behind prostate cancer progression are largely unknown, but macrophage inhibitory cytokine 1 (MIC-1) has been suggested to be involved in tumour dissemination in vivo due to its reductive effect on cell adhesion. MATERIALS AND METHODS: We used two PC-3 prostate cancer epithelial cell line variants as tools to screen for gene expression differences during prostate cancer progression by cDNA microarray analysis. Selected genes were further analysed by Northern blot analysis using mRNA isolated from prostatic cell lines and tissues. MIC-1 expression was studied by in situ hybridization in archival patient specimens containing benign and malignant prostatic tissue. RESULTS: Gene expression of human collagen type VI, basement membrane heparan sulphate proteoglycan, integrin alpha 1, and fibronectin I were remarkably decreased in suspension-adapted PC-3 (saPC-3) cells, indicating a gene expression profile of reduced cell adhesion. Asparagine synthetase, serine protease 1, stanniocalcin homologue, NAD-dependent methylene tetrahydrate dehydrogenase cyclohydrolase (NMDMC), fortilin, and MIC-1 were overexpressed in saPC-3 cells. In prostate, the MIC-1 gene was mainly expressed in cancer tissue. However, MIC-1 transcripts were detected in benign tissue areas, especially in specimens containing prostate cancer with Gleason sum scores of 5-8. A significant inverse correlation (Spearman's rho correlation coefficient -0.928**) was observed between the ratio of cancerous to benign MIC-1 expression levels and Gleason scores. CONCLUSIONS: Differential expression of the MIC-1 gene occurs during prostate cancer progression. The transcript level of the MIC-1 gene in histologically benign tissue seems to approach that in paired cancer tissue concomitant with an increasing Gleason score.

Blotting, Northern↗
PubMed2006

Oxidative/nitrosative stress and peroxiredoxin 2 are associated with grade and prognosis of human renal carcinoma.

Peroxiredoxins (Prxs) 1-6 were assessed in 138 renal cell carcinomas (RCC) using immunohistochemistry and selected samples by Western blotting analysis. Oxidative/nitrosative damage was evaluated using nitrotyrosine immunoreactivity. The expressions of Prxs were correlated with tumor grade and survival and nitrotyrosine reactivity. Non-malignant kidney tubular cells showed positivity with variable intensity for all six Prxs. In RCCs, most cases were positive for Prxs 1 and 2, while only 15-20% of tumors showed expression for Prxs 3 and 4. Prx 2 was associated with tumors of a lower grade (p=0.009) and with a lower frequency of distant metastases (p=0.046). Patients with tumors expressing Prx2 had better prognosis (p=0.027). Instead, nitrotyrosine was significantly associated with high grade tumors (p=0.001). Compared with the non-malignant kidney tubular cells, low Prx expression in the tumor cells can make them more susceptible to oxidative damage. Prx 2 was more abundantly expressed in low grade tumors, suggesting that this protein could play a role in preventing the development of oxidative damage, which in turn can lead to the activation of pathways leading to aggressive tumors.

Adult↗
PubMed2006

Antioxidant enzymes in renal cell carcinoma.

The aim of the study was to estimate the significance of oxidative/nitrosative damage and expression of antioxidant enzymes in renal cell carcinomas (RCC). For this we investigated immunohistochemically six antioxidant enzymes (AOEs) including MnSOD, ECSOD, thioredoxin, thioredoxin reductase, and gammaglutamyl cysteine synthetase heavy and light chain in 138 RCCs. As an indicator of oxidative/nitrosative damage, sections were stained with an antibody to nitrotyrosine. The extent of apoptosis was evaluated by TUNEL method and proliferation by immunohistochemistry to Ki67. Variable expression of all AOEs could be seen in RCC with expression of MnSOD being strongest. Nitrotyrosine was significantly associated with high grade tumors. MnSOD was associated with tumors of a lower stage. Cases showing ECSOD reactivity had higher and cases expressing thioredoxin lower apoptotic index than other tumors. No association with patient prognosis was observed. According to the results renal cell carcinomas show oxidative/nitrosative damage which, according to nitrotyrosine staining, was higher in high grade tumors. Of AOEs, MnSOD was more abundantly expressed in low stage tumors suggesting that its antioxidant function could play a main role to prevent development of oxidative damage leading to more aggressive tumors.

Adult↗
PubMed2003

Membranous location of EGFR immunostaining is associated with good prognosis in renal cell carcinoma.

Epidermal growth factor receptor (EGFR) is a key factor in tumorigenesis. The association between EGFR expression and prognosis in renal cell carcinoma (RCC) is not clear. In our study of 134 RCCs, the cellular location of immunostaining was evaluated and patients with EGFR-positive tumours with prominent membranous staining had a good prognosis. Their overall survival was significantly longer (P=0.004) than that of patients with either EGFR-negative tumours or with mainly cytoplasmic staining. However, further studies on the different EGFR expression patterns in RCC are needed to clarify their role in the progression of the disease.

Adult↗
PubMed2002

Supraglottic and glottic carcinomas. clinically and biologically distinct entities?

This study aimed to examine the clinical and biological differences in 198 patients with either T1-T2 local glottic or supraglottic squamous cell carcinomas. The patients with supraglottic cancer had a poorer prognosis, as well as more advanced and histologically aggressive tumours than the patients with glottic tumours. They also had lower levels of haemoglobin and a poorer nutritional and performance status. Expression of alpha-catenin, hyaluronan, CD44, p53, p21/WAF1 and bcl-2 in the primary tumour were not associated with the site of the laryngeal carcinoma. In supraglottic tumours, the rate of spontaneous apoptosis and mitotic indices were significantly higher than in glottic tumours. The results suggest that clinical parameters including the haemoglobin level of the patient together with the tumour cell kinetics (mitotic and apoptotic rates) may contribute to the aggressive nature of supraglottic carcinoma.

Adult↗
PubMed2001

Prognostic value of hyaluronan expression in non-small-cell lung cancer: Increased stromal expression indicates unfavorable outcome in patients with adenocarcinoma.

The prognostic value of hyaluronan (HA) was analyzed in a large number of patients (n = 261) with non-small-cell lung cancer (NSCLC) by staining archived tumor samples with a biotinylated HA-specific probe. The level of HA in the tumor cells and surrounding stroma was scored and compared with parallel CD44 stainings, clinicopathological factors and survival data. Adenocarcinomas were characterized by a low percentage of HA-positive cells with low staining intensity compared with squamous-cell and large-cell/anaplastic carcinomas. The HA signal in the peri-tumoral stroma was often higher than that in the uninvolved stroma in all subgroups of NSCLC. CD44 and HA associated with the cancer cells showed a strong positive correlation with each other. In the whole tumor material, dominated by squamous-cell carcinomas (n = 168), recurrences were more often found in cases showing a low percentage of cancer cell-associated HA. However, within the adenocarcinoma subgroup (n = 68), a high percentage of cell-associated HA was correlated with poor tumor differentiation. Also specific for the adenocarcinoma subgroup was the increased number of recurrences in cases with a strong stromal HA signal. In survival analysis of the whole material (n = 189), a low percentage of HA-positive cancer cells was associated with a shortened disease-free survival (DFS) together with stage and tumor type. However, in the subgroup of patients with adenocarcinoma (n = 49), a strong stromal signal for HA predicted poor DFS. The level of HA in the stroma of adenocarcinomas retained its prognostic value in Cox's multivariate analysis. These results indicate that the frequency and intensity of HA has a significant prognostic value in NSCLC, particularly when the histological subtypes are analyzed as separate entities.

Adenocarcinoma↗
PubMed2001

Reduced expression of alpha-catenin, beta-catenin, and gamma-catenin is associated with high cell proliferative activity and poor differentiation in non-small cell lung cancer.

AIMS: To investigate the expression of catenins (alpha, beta, and gamma) in non-small cell lung carcinoma (NSCLC) and its relation to clinicopathological factors and prognosis. METHODS: The expression of catenins was analysed immunohistochemically in 261 patients with resected NSCLC, diagnosed between 1978 and 1996 in eastern Finland: The cell proliferation index of the tumours was analysed by means of an image analyser. The staining results were compared with clinicopathological characteristics and survival. RESULTS: Normal catenin staining was found significantly more often in adenocarcinomas than in squamous cell carcinomas or anaplastic/large cell carcinomas. Reduced staining of alpha-catenin, beta-catenin, and gamma-catenin was related to poor differentiation of the tumour. The tumours with reduced staining of beta-catenin or gamma-catenin often had higher cell proliferation activity. Nuclear staining of beta-catenin and gamma-catenin was found in 16 (7%) and 29 (13%) cases, respectively. This nuclear staining correlated directly with increased cell proliferation and inversely with membranous staining. In survival analyses the predictors of overall and disease free survival were stage and tumour type. The expression of catenins did not affect survival. CONCLUSIONS: The expression of alpha-catenin, beta-catenin, and gamma-catenin is related to histological type and differentiation in NSCLC, although catenins have no independent prognostic value. However, this study supports the important role of the nuclear accumulation of beta-catenin and gamma-catenin in highly proliferative cells.

Aged↗
PubMed2000

Merkel cell carcinoma of the auricle.

Merkel cell carcinoma is a rare, although increasingly recognized, malignant tumor of the skin. The most common site of occurrence is the head and neck (50%). Only five cases of this tumor on the auricle have been reported previously. We present a further such case. The incidence, clinical features, diagnosis, prognosis, and treatment of the Merkel cell carcinoma are discussed.

Aged↗
PubMed2000

Hyaluronan in peritumoral stroma and malignant cells associates with breast cancer spreading and predicts survival.

Hyaluronan (HA) is an extracellular matrix polysaccharide that promotes cell migration through its cell surface receptors and by effecting changes in the physical environment. HA expression is frequently increased in malignant tumors, whereas its association with the invasive potential and patient outcome in breast cancer has not been reported. The localization and signal intensity of HA was analyzed in 143 paraffin-embedded tumor samples of human breast carcinoma using a biotinylated HA-specific probe. In the immediate peritumoral stroma, HA signal was moderately or strongly increased in 39% and 56% of the cases, respectively. Normal ductal epithelium showed no HA, whereas in 57% of the tumors at least some of the carcinoma cells were HA positive. The intensity of the stromal HA signal and the presence of cell-associated HA were both significantly related to poor differentiation of the tumors, axillary lymph node positivity, and short overall survival of the patients. In Cox's multivariate analysis, both the intensity of stromal HA signal alone and that combined with the HA positivity in tumor cells were independent prognostic factors for overall survival. These results suggest that HA is directly involved in the spreading of breast cancer and may offer a potential target for new therapies.

Axilla↗
PubMed2000

Reduced expression of CD44v3 variant isoform is associated with unfavorable outcome in non-small cell lung carcinoma.

The expression of CD44 standard form (CD44s) and variant isoforms v3 and v6 was analyzed in 233 resected non-small cell lung carcinoma (NSCLC) specimens by immunohistochemistry (IHC), and the mRNA status of CD44v3 and CD44v6 in a cohort of samples was determined by in situ hybridization (ISH) and further confirmed by reverse transcriptase polymerase chain reaction (RT-PCR). The expression of CD44s, CD44v3, and CD44v6 was correlated with clinicopathologic variables and survival. The expression of CD44v3 and v6 was reduced in 97% and 90% of the adenocarcinomas and in 86% and 74% of the large cell/anaplastic carcinomas, respectively, as compared with squamous cell carcinomas, where they were reduced in 53% and 51% of the cases (P = .0001 and P = .004 for v3 and v6). The corresponding values for CD44s were 92%, 70%, and 51%, respectively (P = .011). The reduced CD44s and CD44v6 expression was associated with lymph node metastases (P = .03 and P = .005, respectively) and the reduced expression of CD44s also with advanced stage (P = .04). Recurrences during the follow-up were more often found within the tumors showing reduced expression of CD44v3 (P = .04). Combining ISH and IHC results showed that CD44v3 and v6 mRNA were not always processed into protein, suggesting a regulation disturbance posttranscriptionally since malignant transformation of cells has occurred. In survival analyses, the reduced expression of CD44s and CD44v3 was associated with a shortened disease-free survival (P = .04 and P = .01, respectively). In multivariate analysis, CD44v3 retained its independent prognostic value (P = .03). These results emphasize the value of CD44, and especially the v3 variant isoform in the behavior of NSCLC.

Adult↗
PubMed2000

p53 and K-ras gene mutations in carcinoma of the rectum among Finnish women.

AIMS/BACKGROUND: The aim of this study was to identify p53 and K-ras gene mutations in carcinoma of the rectum among Finnish women. Mutation patterns might give clues to aetiological factors when comparisons are made with other human tumours. METHODS: Of 134 women with carcinoma of the rectum, paraffin wax embedded specimens of the tumour tissue were obtained from 118 patients. Genomic DNA was extracted, and exons 4-8 of the p53 gene and codons 12/13 and 61 of the K-ras gene were amplified, and analysed for mutations by single strand conformation polymorphism and direct sequencing. The production of p53 and K-ras proteins was studied by immunohistochemistry. RESULTS: The overall crude frequency for mutations in the p53 gene was 35% but the true frequency appears to be higher (up to 56%). In the K-ras gene, the mutation frequency (15%) was significantly lower than that reported for colon cancer. In the p53 gene, the mutation frequency increased significantly with patient age. In a high proportion of patients (14%) the rectal tumours contained small subclones of tumour cells that displayed extremely rare mutations at codons 110 and 232 of the p53 gene. Hot spot codon 175 mutations were significantly less common in rectal cancer than in cancer of the colon. CONCLUSIONS: Rectal cancer among Finnish women has characteristics in the mutations of the p53 and K-ras genes that are uncommon in other human tumours, including cancer of the colon. A biological explanation of these findings is not clear at present, but might be associated with an unidentified genetic factor in Finland.

Age Factors↗
PubMed1999

Irregular expression of hyaluronan and its CD44 receptor is associated with metastatic phenotype in laryngeal squamous cell carcinoma.

The distributions of hyaluronan (HA) and its CD44 receptor were studied in 24 normal, 27 dysplastic samples of laryngeal epithelium and in 172 squamous cell carcinomas (LSCC), using a specific probe prepared from cartilage proteoglycan (bHABC, biotinylated hyaluronan binding complex) and a monoclonal antibody (Hermes 3). HA and CD44 were expressed similarly in all normal and about 90% of dysplastic and neoplastic laryngeal epithelia. In the normal epithelium HA and CD44 were homogeneously distributed throughout the epithelium, whereas the most superficial layers were negative. This was in contrast to the picture in dysplastic epithelium and well-differentiated invasive carcinomas, which were entirely HA and CD44 positive. Local areas with a low signal for HA and CD44 were present in 11% and 22% of the samples with dysplasia, and in 27% and 28% of those with carcinoma, respectively. The presence of this staining irregularity was associated with poor differentiation of the carcinoma, a significantly elevated mitotic index and a high frequency of nodal spreading and metastases. Furthermore, the irregular staining showed a trend towards poor disease-free survival, suggesting that an altered metabolism of HA is a common feature in LSCC and is associated with an aggressive growth pattern.

Carcinoma, Squamous Cell↗
PubMed1999

Enhanced apoptosis correlates with poor survival in patients with laryngeal cancer but not with cell proliferation, bcl-2 or p53 expression.

The purpose of the current study was to analyse apoptosis and bcl-2 expression in laryngeal squamous cell carcinoma (SCC) with special reference to their prognostic significance, correlation with the clinical and pathological characteristics as well as cell proliferation and p53 accumulation. 172 patients with primary laryngeal SCC were followed-up for a median of 67 months. The volume corrected apoptotic (A/V) index was analysed using an in situ end labelling method (TUNEL) in 85 randomly selected patients. The expression of bcl-2 and p53 was analysed with monoclonal antibodies. The proliferative activity was measured both with Ki-67 (MIB-1) antibody and the volume corrected mitotic (M/V) index. The A/V index was not associated with p53 (P = 0.6) or bcl-2 (P = 0.6) expression or with proliferative parameters (P = 0.9 for M/V and P = 0.3 for MIB-1). The 10-year overall survival in patients with a high A/V index was poorer when compared with patients with a low index (47% versus 81%, P = 0.005), while accumulation of bcl-2 had no prognostic significance (P = 0.5). In Cox multivariate analysis of the whole cohort, stage (P < 0.0005) and histological grade (P = 0.04) were predictors of overall survival. In the subset of patients with an A/V index available, predictors of survival were stage (P = 0.05), A/V index (P = 0.02) and histological grade (P = 0.04). A high A/V index was an independent predictor of poor survival in laryngeal SCC. This effect was not associated with tumour cell proliferation. Accumulations of p53 and bcl-2 were not associated with apoptosis. Expression of bcl-2 lacks any prognostic significance in laryngeal SCC. We propose that assessment of the A/V index may help in selecting patients with poor prognosis.

Adult↗
PubMed1999

Downregulation of p21/WAF1 is related to advanced and dedifferentiated laryngeal squamous cell carcinoma.

AIM: To analyse p21/WAF1 expression and its relation to p53, apoptosis, cell proliferation, clinicopathological characteristics, and patient survival in human laryngeal squamous cell carcinoma. METHODS: Primary tumours for analyses were obtained from 172 patients with complete follow up data. All patients were treated between 1975 and 1995. Immunohistochemistry was used to evaluate the expression of p21/WAF1, bcl-2, and p53 proteins. The proliferative activity was determined using Ki67 and PCNA antibodies as well as volume corrected mitotic count (M/V index). Volume corrected apoptotic count (A/V index) was determined using an enzymatic in situ cell death detection kit based on the TUNEL method. RESULTS: High p21 expression was significantly related to high p53 and normal bcl-2 expressions as well as low mitotic count. No association was noticed between p21 expression and apoptotic rate. A significant inverse correlation between p21 expression and advanced stage and poor differentiation was observed, but p21 expression showed no correlation with survival. CONCLUSIONS: The expression of p21 was associated with tumour stage, histopathological grade, node status, and mitotic count, which may indicate a role for p21 in the progression of laryngeal squamous cell carcinoma.

Adult↗
PubMed1998

Cytoplasmic accumulation of alpha-catenin is associated with aggressive features in laryngeal squamous-cell carcinoma.

Aberrations in the function of alpha-catenin (alpha-cat), the anchoring protein of E-cadherin, are believed to cause dysfunction of the cadherin-catenin complex, leading to disturbed cell-cell adhesion. It has been suggested that expression of alpha-cat in human tumours might be a better indicator of aggressive phenotype than expression of E-cadherin. The value of alpha-cat as a prognostic marker in laryngeal squamous cell carcinoma (LSCC) is unclear. To determine the potential prognostic significance of alpha-cat, paraffin-embedded samples from 159 patients with invasive carcinoma left in the section and with long-term follow-up were evaluated immuno-histochemically for alpha-cat expression, and the results were related to histopathological grade, tumour stage and survival. Two patterns of staining were observed: pure membranous staining (57%) and membranous staining with cytoplasmic involvement (43%). Cytoplasmic involvement of alpha-cat was associated with dedifferentiation, advanced tumour stage and nodal status. In addition, supra-glottic tumours showed more often cytoplasmic involvement of alpha-cat than glottic tumours. Patients with cytoplasmic involvement appeared to have a trend towards poor overall survival, though without statistical significance. These results suggest that cytoplasmic involvement of alpha-cat is associated with aggressive behaviour and metastatic phenotype of LSCC.

Adult↗
PubMed1997

p53 expression and cell proliferation as prognostic factors in laryngeal squamous cell carcinoma.

PURPOSE: To investigate the prognostic significance of p53 expression and proliferation markers in primary laryngeal squamous cell carcinoma. PATIENTS AND METHODS: Primary tumors for analyses were obtained from 103 patients, with complete follow-up data. All patients were treated between the years 1975 and 1990. The expression of p53 was analyzed with monoclonal D07 antibody and proliferative activity with Ki-67 (MIB-1) and PCNA (monoclonal 19A2) antibodies. Volume corrected mitotic (M/V) index and histological grade were determined in hematoxylin and cosin-stained slides. RESULTS: Sixty-eight percent of the tumors overexpressed p53. During a median follow-up of 62 months, 41 (40%) of patients relapsed. In univariate analysis site of the primary tumor, stage, p53 expression, histologic grade, and M/V index were significant predictors of disease-free survival. In multivariate analysis, only M/V index was a statistically significant predictor of disease-free survival. Overall survival was significantly better for those overexpressing p53 (10-year cumulative survival rate 68% v 44%, P = .004). In multivariate analysis, M/ V index (P = .02), p53 (P = .02), and stage (P = .007) were statistically significant predictors of overall survival. When this analysis includes stratification according to the type of treatment received, M/V index (P = .007), stage (P = .0002), and p53 (P = .006) were even more significant predictors of overall survival. No association between p53 status and proliferative activity was found. CONCLUSION: Overexpression of p53 is associated with favorable disease-free and overall survival in laryngeal squamous cell carcinoma. It may also have an independent prognostic value in laryngeal cancer. M/V index, p53 overexpression, and stage predict with significant accuracy the 10-year overall survival.

Adult↗