Human chorionic gonadotropin in pregnancy and maternal risk of breast cancer

Full-term pregnancies are associated with long-term reductions in maternal risk of breast cancer, but the biological determinants of the protection are unknown. Experimental observations suggest that human chorionic gonadotropin (hCG), a major hormone of pregnancy, could play a role in this association. A case-control study (242 cases and 450 controls) nested within the Northern Sweden Maternity Cohort included women who had donated a blood sample during the first trimester of a first full-term pregnancy. Total hCG was determined on Immulite 2000 analyzer. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through conditional logistic regression. Maternal breast cancer risk decreased with increasing hCG (upper tertile OR, 0.67; CI, 0.46-0.99), especially for pregnancies before age 25 (upper tertile OR, 0.41; CI, 0.21-0.80). The association diverged according to age at diagnosis: risk was reduced after age 40 (upper tertile OR, 0.60; CI, 0.39-0.91) and seemed to increase before age 40 (upper tertile OR, 1.78; CI, 0.72-4.38). Risk was reduced among those diagnosed 10 years or longer after blood draw (upper tertile OR, 0.60; CI, 0.40-0.90), but not so among those diagnosed within 10 years (upper tertile OR, 4.33; CI, 0.86-21.7). These observations suggest that the association between pregnancy hCG and subsequent maternal risk of breast cancer is modified by age at diagnosis. Although the hormone seems to be a determinant of the reduced risk around or after age 50, it might not confer protection against, or it could even increase the risk of, cancers diagnosed in the years immediately following pregnancy.

Is the test result correct? A questionnaire study of blood collection practices in primary health care

RATIONALE, AIMS AND OBJECTIVES

Venous blood tests are important for clinical decision making. Most errors in blood testing are due to human errors before the blood samples reach the laboratory. The present study was designed to investigate venous blood sampling (VBS) practices in primary health care centres (PHCs) compared with clinical laboratory staff.

METHOD

A cross-sectional survey of 70 PHCs and two clinical laboratories is conducted. All staff responsible for VBS (317 respondents, response rate 94%) completed a questionnaire on VBS practices.

RESULTS

Instructions for VBS were not followed in the surveyed PHCs. For example, only 54% reported that they always identified the patient by using name/Swedish identification number and only 5% reported that they always used photo-ID, the two preferred means for patient identification. Only 12% reported that they always released venous stasis as soon as possible. Fewer PHC staff than clinical laboratory staff reported correct VBS practices. For example, 54% of the PHC staff reported that they always identified the patient by name and Swedish identification number, as compared with 95% of the clinical laboratory staff (P < 0.001). Documented VBS routines and re-education in VBS were not clearly associated with reported correct VBS practices.

CONCLUSIONS

In the surveyed PHCs, there are clinically important risks for misidentification of patients and erroneous test results, with consequences for the diagnosis and treatment of patients. Quality interventions, aimed at improving VBS practices, are needed to ensure patient safety.

Soluble carbonic anhydrase IX is not an independent prognostic factor in human renal cell carcinoma

The aim of this study was to evaluate the prognostic information of soluble carbonic anhydrase (CA) IX expression in renal cell carcinoma (RCC).

PATIENTS AND METHODS

Serum CA IX was analysed in 361 patients. Tumour type, TNM stage, nuclear grade, and RCC-specific survival were assessed. Serum and immunohistochemical expression were compared.

RESULTS

Median serum CA IX expression was 141 (range 2-4, 181) pg/ml. Levels were significantly higher in 287 patients with clear cell, compared to 40 papillary (p<0.001) and 22 oncocytoma (p=0.002), but not to 12 chromophobe RCC (p=0.35). Serum CA IX in clear cell RCC was positively correlated to TNM stage (p=0.002). There was a positive trend between serum and immunohistochemical CA IX expression. In a multivariate analysis of clear cell RCC, TNM stage and nuclear grade were independent prognostic factors.

CONCLUSION

Serum CA IX was higher in clear cell RCC compared to other RCC types. In clear cell RCC, serum CA IX correlated to TNM stage, but not survival.

Independent and joint effects of serum 25-hydroxyvitamin D and calcium on ovarian cancer risk: a prospective nested case-control study

INTRODUCTION

Ovarian cancer has very few known modifiable risk factors but dietary studies suggest a role for vitamin D and calcium in the prevention of ovarian cancer. Thus, we investigated the association between pre-diagnostic serum calcium and 25-hydroxyvitamin D (25-OHD) on the risk of later development of ovarian cancer.

METHODS

We conducted a population-based nested case-control study within the Finnish Maternity Cohort (FMC). The cohort subset comprised 172 ovarian cancer cases with 172 matched controls (age ± 1 year, parity and season of blood donation ± 2 weeks).

RESULTS

We observed a significant inverse association between calcium and ovarian cancer risk. Relative risk (estimated as odds ratio, OR) comparing the highest quartile to the lowest quartile was significantly decreased; 0.41 [95% confidence interval (CI) 0.19-0.85, P-trend 0.004]. Even though a comparable association between 25-OHD and ovarian cancer did not reach statistical significance (OR 0.57, 95% CI 0.26-1.24, P-trend 0.07), having sufficient (> 75 nmol/L) serum 25-OHD levels compared to insufficient serum 25-OHD was associated with a significantly decreased risk of ovarian cancer (OR 0.32; 95% CI 0.12-0.91, p-value 0.03). No synergistic protective interaction between high levels of calcium and 25-OHD against ovarian cancer was observed, the joint effect being just multiplicative.

CONCLUSION

Calcium and vitamin D act independently to reduce the risk of ovarian cancer. The decreased risk of ovarian cancer associated with pre-diagnostic serum calcium and vitamin D needs to be evaluated further for possible new insights into ovarian cancer prevention.

The effects of storage time and sampling season on the stability of serum 25-hydroxy vitamin D and androstenedione

Knowledge of the stability of serum samples stored in large biobanks is pivotal for reliable assessment of hormone-dependent disease risks. We studied the effects of sample storage time and season of serum sampling on the stability of 25-hydroxy vitamin D (25-OHD) and androstenedione in a stratified random sample of 402 women, using paired sera from the Finnish Maternity Cohort. Serum samples selected were donated between 6 and 24 yr ago. The storage time did not affect serum 25-OHD and androstenedione levels. However, there was a significant mean difference in the 25-OHD levels of sera withdrawn during winter (first sample) vs. during summer (second sample; -18.4 nmol/l, P <or= 0.001). Also at the individual level, there were significant differences in average 25-OHD levels between individuals with the paired sera taken at winter-winter compared with other alternatives (summer-winter, winter-summer, and summer-summer). The androstenedione levels showed no such differences. Long-term storage does not affect serum 25-OHD and androstenedione levels, but sampling season is an important determinant of 25-OHD levels. Stored serum samples can be used to study disease associations with both hormones. However, sampling season needs to be taken into account for 25-OHD by considering matching and stratification and, if possible, serial sampling.

Incident reporting practices in the preanalytical phase: Low reported frequencies in the primary health care setting

OBJECTIVE

Incident reporting is commonly used to improve patient safety. The preanalytical phase of laboratory testing contains several manual error-prone tasks where mistakes can affect patient outcomes. However, the practical use of incident reports in this area has not been previously investigated in the primary health care setting, where the majority of the patients come in contact with health care.

MATERIAL AND METHODS

All staff responsible for venous blood sampling in 70 primary health care centres and in two hospital clinical laboratories (317 respondents, response rate 94%) completed a questionnaire.

RESULTS

Of the primary health care staff, 69% reported that they had never filed an incident report regarding venous blood sampling. Barriers for not filing incident reports often/always included lack of time (44%) and a complicated reporting procedure (27%). A higher proportion of staff with re-education (43%) had filed at least one incident report as compared to those without re-education (20%, p < 0.001). No differences in incident reporting practices were found between primary health care and hospital clinical laboratory staff.

CONCLUSIONS

The investigated incident reporting system is likely to underreport incidents in the preanalytical phase. Therefore, the ability to discover preventable system vulnerabilities needs refinement.

IGF-I during primiparous pregnancy and maternal risk of breast cancer

Previously, we reported that insulin-like growth factor (IGF)-I during early pregnancy is positively associated with maternal risk of breast cancer. To further explore this association, we designed a new study limited to women who donated a blood sample during their first pregnancy ending with childbirth. A case-control study was nested within the Northern Sweden Maternity Cohort in which repository since 1975, serum specimens remaining after early pregnancy screening for infectious diseases had been preserved. Study subjects were selected among women who donated a blood sample during the full-term pregnancy that led to the birth of their first child. Two hundred and forty-four women with invasive breast cancer were eligible. Two controls, matching the index case for age and date at blood donation were selected (n = 453). IGF-I was measured in serum samples on an Immulite 2000 analyzer. Conditional logistic regression was used to estimate odds ratios and 95% confidence intervals. A significant positive association of breast cancer with IGF-I was observed, with OR of 1.73 (95% CI: 1.14-2.63) for the top tertile, P < 0.009. Subgroup analyses did not indicate statistical heterogeneity of the association by ages at sampling and diagnosis or by lag time to cancer diagnosis, although somewhat stronger associations with risk were observed in women < or = age 25 at index pregnancy and for cases diagnosed within 15 years of blood donation. The results of the study add further evidence for an adverse effect of elevated IGF-I concentrations during early reproductive life on risk of breast cancer.

Hypoxia-inducible factor-2alpha mRNA expression in human renal cell carcinoma

BACKGROUND

Hypoxia-inducible factor (HIF)-2alpha is upregulated in hypoxia or by inactivation of the von Hippel-Lindau (VHL) tumour suppressor gene. In a number of malignancies, increased HIF-2alpha expression may indicate worse prognosis. The aim of this study was to evaluate the prognostic information of HIF-2alpha mRNA expression in renal cell carcinoma (RCC).

MATERIAL AND METHODS

HIF-2alpha mRNA was quantified by real time polymerase chain reaction (rt-PCR) in tumour tissue samples from 202 patients. Samples from 50 corresponding kidney cortex tissue were analysed as controls. mRNA levels were evaluated in relation to tumour cell type, TNM stage, nuclear grade and disease specific survival.

RESULTS

The levels of HIF-2alpha mRNA were significantly higher in 168 clear cell (c)RCC than in 23 papillary (p)RCC (p < 0.001) or 11 chromophobe (ch)RCC (p < 0.006). Among cRCC there was an inverse correlation between HIF-2alpha mRNA levels and TNM stage I and II-IV tumours (p=0.01), and nuclear grade (p = 0.006). After a median follow-up time of 99 months (range 34-247), 106 patients had died of RCC. No correlation of HIF-2alpha mRNA to survival was observed. A multivariate analysis of prognostic factors in cRCC showed that TNM stage alone was an independent predictor of prognosis; HIF-2alpha mRNA levels did not add further prognostic information.

DISCUSSION

The results demonstrated that HIF-2alpha mRNA levels were higher in cRCC compared to pRCC and chRCC. Furthermore, HIF-2alpha mRNA levels were inversely related to TNM stage and nuclear grade in cRCC.

Patient‐centred care – preanalytical factors demand attention: A questionnaire study of venous blood sampling and specimen handling

OBJECTIVE

Most mistakes in laboratory medicine are the result of human error occurring before the blood sample reaches the laboratory. This survey of preanalytical procedures was designed to identify sources of error and potential targets for quality improvement strategies.

MATERIAL AND METHODS

The staff in a highly specialized surgical ward at a university hospital completed a questionnaire addressing the collection and handling of venous blood samples in plastic vacuum test-tubes for general clinical chemistry testing.

RESULTS

The results suggest that venous blood sampling instructions are not always followed. When uncertain about how a sample should be collected, the majority of respondents rely on potentially poor sources of information, such as out-of-date printed instructions or the advice of a colleague, rather than consult up-to-date electronic instructions. Furthermore, they do not always report errors and the referrals are not always handled according to sampling instructions. The respondents were highly motivated, however, and had a strong interest in receiving further education in, and assuming increased responsibility for, venous blood sampling procedures in the ward.

CONCLUSIONS

We believe that the introduction of standardized routines and regular staff training, combined with an exchange of the existing paper-based referral management system with an electronic system for managing referrals, could increase safety in the preanalytical process, with positive effects on patient safety. Given the importance of venous blood samples in patient care, a more extensive study covering other hospital wards and primary health-care centres is needed.

Serum insulin-like growth factor-1 is an independent predictor of prognosis in patients with renal cell carcinoma

Obesity is associated with an increased risk of certain cancers, including renal cell carcinoma. A possible mediator of this risk is insulin-like growth factor-1 (IGF-1). The authors evaluated the prognostic information of IGF-1, IGFBP-3, leptin, and prealbumin in sera sampled at diagnosis from 256 consecutive patients with renal cell carcinoma. Insulin-like growth factor-1 and leptin were positively correlated to body mass index (BMI). Insulin-like growth factor-1 and IGFBP-3 did not correlate to tumour stage or grade. Leptin and prealbumin were both inversely related to tumour stage and grade. When survival was analysed in patients with levels above a median of IGF-1, leptin, and prealbumin, prognosis was more favourable, compared with those with lower levels (p=0.017; p=0.024, and p<0.0001, respectively). In a multivariate analysis, tumour stage and serum IGF-1 levels were independent prognostic factors. The results indicate that serum IGF-1 at diagnosis is related to prognosis in renal cell carcinoma.

Expression of erythropoietin and its receptor in human renal cell carcinoma

OBJECTIVE

To investigate the prognostic impact of erythropoietin (EPO) and EPO-receptor (EPO-R) expression in tumour as well as serum EPO in patients with renal cell carcinoma (RCC).

METHODS

Using immunohistochemistry, EPO and EPO-R were assessed in tissue microarrays from 195 RCCs. RCC type, TNM stage, nuclear grade, survival, EPO and haemoglobin (Hb) levels in blood were registered.

RESULTS

Strong expression of EPO and EPO-R in tumour tissue was found in 83 and 56%, respectively. EPO and EPO-R expression differed between RCC types. Serum EPO and blood Hb did not correlate to the expression of EPO or EPO-R. A positive correlation was found between the expression of EPO and EPO-R (p = 0.028). Survival was not related to tumour EPO, whereas strong EPO-R expression indicated a non-significantly worse prognosis. Serum EPO correlated positively to TNM stage and nuclear grade and negatively to survival. A multivariate analysis showed that TNM stage and nuclear grade were independent prognostic factors. Tumour EPO and EPO-R expression as well as serum EPO added no independent prognostic information.

CONCLUSION

No correlation between EPO or EPO-R in tumour tissue and serum EPO or blood Hb was found. Neither EPO, EPO-R in tumour tissue nor serum EPO are independent prognostic factors.

Misleading T3-test values in psychiatric patients treated with orphenadrine

Thyroid laboratory tests were assessed in 74 psychiatric patients without clinical evidence of overt thyroid disorder. In a first screening of 42 patients, 13 were found to have elevated levels of triiodothyronine uptake test (T3-test) by a Sephadex method. Ten of these patients also had an elevated free thyroxine index (fT4-index). Of the 13 patients with increased T3-test values, 10 were on orphenadrine (Disipal) treatment or had recently stopped taking the drug. In a second study, thyroid function tests were compared in 15 pairs of matched psychiatric patients treated with orphenadrine or other anticholinergic drugs. Values of T3-test and free thyroxine index were significantly higher among patients treated with orphenadrine. Finally, orphenadrine was instituted in four patients and withdrawn in six patients. T3-test values and free thyroxine indices increased gradually after orphenadrine treatment had been initiated and decreased gradually when it was withdrawn.

C-reactive protein and ovarian cancer: a prospective study nested in three cohorts (Sweden, USA, Italy)

OBJECTIVES

Inflammatory processes may influence the risk of epithelial ovarian cancer, but available epidemiological evidence is limited and indirect. Circulating C-reactive protein (CRP), a sensitive marker of inflammation, may serve as a direct biological marker of an underlying association.

METHODS

The association between ovarian cancer risk and pre-diagnostic circulating CRP was tested in a case-control study nested within three prospective cohorts from Sweden, USA, and Italy. The study included 237 cases and 427 individually matched controls. CRP was measured in stored blood samples by high-sensitivity immunoturbidimetric assay. Odds ratios (OR) and 95% confidence intervals (CI) were calculated by conditional logistic regression.

RESULTS

Overall, CRP was not related to risk of ovarian cancer. However, a marked increase in risk was observed for CRP concentrations >10 mg/l: OR (95% CI) 4.4 (1.8-10.9), which remained significant after limiting analyses to cases diagnosed more than two or five years after blood donation (OR 3.0 (1.2-8.0) and 3.6 (1.0-13.2), respectively). Risk of mucinous tumors increased with high CRP, but the number of cases in this analysis was small.

CONCLUSION

Study results offer additional support to the concept that chronic inflammation plays a role in epithelial ovarian cancer.

Preanalytical errors in primary healthcare: a questionnaire study of information search procedures, test request management and test tube labelling

: Most errors in laboratory medicine occur in the preanalytical phase and are the result of human mistakes. This study investigated information search procedures, test request management and test tube labelling in primary healthcare compared to the same procedures amongst clinical laboratory staff.

: A questionnaire was completed by 317 venous blood sampling staff in 70 primary healthcare centres and in two clinical laboratories (response rate = 94%).

: Correct procedures were not always followed. Only 60% of the primary healthcare staff reported that they always sought information in the updated, online laboratory manual. Only 12% reported that they always labelled the test tubes prior to drawing blood samples. No major differences between primary healthcare centres and clinical laboratories were found, except for test tube labelling, whereby the laboratory staff reported better practices. Re-education and access to documented routines were not clearly associated with better practices.

: The preanalytical procedure in the surveyed primary healthcare centres was associated with a risk of errors which could affect patient safety. To improve patient safety in laboratory testing, all healthcare providers should survey their preanalytical procedures and improve the total testing process with a systems perspective.

Clin Chem Lab Med 2009;47:195–201.

Human chorionic gonadotropin and alpha-fetoprotein concentrations in pregnancy and maternal risk of breast cancer: a nested case-control study

Pregnancy hormones are believed to be involved in the protection against breast cancer conferred by pregnancy. The authors explored the association of maternal breast cancer with human chorionic gonadotropin (hCG) and alpha-fetoprotein (AFP). In 2001, a case-control study was nested within the Northern Sweden Maternity Cohort, an ongoing study in which blood samples have been collected from first-trimester pregnant women since 1975. Cases (n = 210) and controls (n = 357) were matched for age, parity, and date of blood donation. Concentrations of hCG and AFP were measured by immunoassay. No overall significant association of breast cancer with either hCG or AFP was observed. However, women with hCG levels in the top tertile tended to be at lower risk of breast cancer than women with hCG levels in the lowest tertile in the whole study population and in subgroups of age at sampling, parity, and age at cancer diagnosis. A borderline-significant decrease in risk with high hCG levels was observed in women who developed breast cancer after the median lag time to cancer diagnosis (> or =14 years; odds ratio = 0.53, 95% confidence interval: 0.27, 1.03; P = 0.06). These findings, though very preliminary, are consistent with a possible long-term protective association of breast cancer risk with elevated levels of circulating hCG in the early stages of pregnancy.

Acquisition of cisplatin-resistance in malignant mesothelioma cells abrogates Na+,K+,2Cl(-)-cotransport activity and cisplatin-induced early membrane blebbing

AIMS

Resistance mechanisms are important limiting factors in the treatment of solid malignancies with cis-diamminedichloroplatinum(II) (cisplatin). To gain further understanding of the effects of acquired cisplatin-resistance, we compared a human malignant pleural mesothelioma cell line (p31) to a sub-line (p31res1.2) with acquired cisplatin-resistance.

METHODS AND RESULTS

The role of Na(+),K(+),2Cl(-)-cotransport (NKCC1) activity in cisplatin-induced morphological changes and acquired cisplatin-resistance was investigated in a time-resolved manner. Acquisition of cisplatin-resistance resulted in markedly reduced NKCC1 activity, absence of cisplatin-induced early membrane blebbing, and increased basal caspase-3 activity. At equitoxic cisplatin concentrations, P31res1.2 cells had a faster activation of caspase-3 than P31 cells, but the end-stage cytotoxicity and number of cells with DNA fragmentation was similar. Bumetanide inhibition of NKCC1 activity in P31 cells repressed cisplatin-induced early-phase membrane blebbing but did not increase P31 cell resistance to cisplatin.

CONCLUSIONS

Together, these results suggest that active NKCC1 was necessary for cisplatin-induced early membrane blebbing of P31 cells, but not for cisplatin-resistance. Thus, acquisition of cisplatin-resistance can affect mechanisms that have profound effects on cisplatin-induced morphological changes but are not necessary for the subsequent progression to apoptosis.

Glucose transporter-1 expression in renal cell carcinoma and its correlation with hypoxia inducible factor-1 alpha

OBJECTIVE

To evaluate transcription factor hypoxia inducible factor-1 alpha (HIF-1 alpha) activity, by analysing a target gene for HIF-1 alpha, glucose transporter-1 (GLUT-1), using a tissue microarray (TMA) in different types of renal cell carcinoma (RCC, a tumour with a variable clinical course, partly due to angiogenic activity), as angiogenesis is important for tumour progression and metastatic spread, and is activated by hypoxia.

PATIENTS AND METHODS

GLUT-1 and HIF-1 alpha expressions were semiquantitatively analysed using immunohistological staining of a prepared TMA, using samples from 187 patients, including 148 with conventional, 26 with papillary and 13 with chromophobe RCC.

RESULTS

GLUT-1 staining was found mainly in the cytoplasm. The tumours were subdivided into GLUT -1(LOW) and GLUT-1(HIGH), based on staining intensity. There was a significant difference in GLUT-1 expression between RCC types (P < 0.05). In conventional RCC, GLUT-1 had no correlation with clinicopathological variables. By contrast there was a correlation with tumour stage in papillary RCC. There was an insignificant trend to better survival of patients with GLUT-1(LOW) expression in both conventional and papillary RCC. GLUT-1 correlated significantly (P = 0.008) with HIF-1 alpha.

CONCLUSIONS

Most patients with conventional RCC had GLUT-1(HIGH) staining and there was a significant correlation with HIF-1 alpha. In papillary RCC, GLUT-1 expression was associated with stage; GLUT-1 expression was significantly higher in conventional RCC than in papillary and chromophobe RCC. GLUT-1(LOW) in both papillary and conventional RCC appeared to correspond with a better prognosis.

Effect of long-term storage on hormone measurements in samples from pregnant women: the experience of the Finnish Maternity Cohort

Validity of biobank studies on hormone associated cancers depend on the extent the sample preservation is affecting the hormone measurements. We investigated the effect of long-term storage (up to 22 years) on immunoassay measurements of three groups of hormones and associated proteins: sex-steroids [estradiol, progesterone, testosterone, dihydroepiandrosterone sulphate (DHEAS), sex hormone-binding globulin (SHBG)], pregnancy-specific hormones [human chorionic gonadotropin (hCG), placental growth hormone (pGH), alpha-fetoprotein (AFP)], and insulin-like growth factor (IGF) family hormones exploiting the world largest serum bank, the Finnish Maternity Cohort (FMC). Hormones of interest were analyzed in a random sample of 154 Finnish women in the median age (29.5 years, range 25 to 34 years) of their first pregnancy with serum samples drawn during the first trimester. All hormone measurements were performed using commercial enzyme-linked- or radio-immunoassays. Storage time did not correlate with serum levels of testosterone, DHEAS, hCG, pGH and total IGFBP-1. It had a weak or moderate negative correlation with serum levels of progesterone (Spearman's ranked correlation coefficient (r(s))=- 0.36), IGF-I (r(s)=-0.23) and IGF binding protein (BP)-3 (r(s)=-0.38), and weak positive correlation with estradiol (r(s)=0.23), SHBG (r(s)=0.16), AFP (r(s)=0.20) and non-phosphorylated IGF binding protein (BP)-1 (r(s)=0.27). The variation of all hormone levels studied followed the kinetics reported for early pregnancy. Bench-lag time (the time between sample collection and freezing for storage) did not materially affect the serum hormone levels. In conclusion, the stored FMC serum samples can be used to study hormone-disease associations, but close matching for storage time and gestational day are necessary design components of all related biobank studies.

Prognostic impact of carbonic anhydrase IX expression in human renal cell carcinoma

OBJECTIVE

To evaluate the prognostic information of carbonic anhydrase (CA) IX expression in patients with renal cell carcinoma (RCC), as increased expression of CA IX is correlated with a worse prognosis in several malignancies.

PATIENTS AND METHODS

CA IX expression was assessed in RCC tumours from 228 patients, using a tissue microarray technique on archival material. The expression was related to RCC cell type, Tumour-Node-Metastasis (TNM) stage, nuclear grade and survival.

RESULTS

CA IX expression was significantly higher (P < 0.001) in 183 conventional than in 31 papillary RCC and 14 chromophobe RCC. For conventional RCC there was no correlation of CA IX expression with TNM stage or nuclear grade. To evaluate the prognostic information conventional RCC tumours were subdivided arbitrarily into three groups according to the CA IX expression, of 0-10%, 11-90% and 91-100% expression, respectively. Patients with tumours with 0-10% expression had a less favourable prognosis than those with 11-90% and 91-100% expression (P = 0.012, and 0.001), respectively. A multivariate analysis of prognostic factors for patients with conventional RCC showed that TNM stage, nuclear grade and CA IX were independent predictors of prognosis.

CONCLUSION

These results show that CA IX expression is higher in conventional than other RCC cell types; furthermore, patients with conventional RCC with low CA IX expression had a less favourable prognosis.

Evaluation of CD31 (PECAM-1) expression using tissue microarray in patients with renal cell carcinoma

Intratumoural microvessel density (MVD) has prognostic significance in selected neoplasms. To evaluate the prognostic information of MVD in renal cell carcinoma (RCC) we assessed the immunohistochemical expression of CD31 in 208 tumours using the tissue microarray technique. The expression was related to tumour cell type, TNM stage, nuclear grade and survival. CD31 expression was significantly (p < 0.001) higher in 167 conventional RCCs (clear cell) compared to 28 papillary RCCs. In conventional RCC, CD31 expression was inversely correlated to TNM stage (p = 0.024) and nuclear grade (p = 0.010). To evaluate the impact of CD31 expression on tumour-specific survival, the conventional RCC tumours were subdivided into quartiles according to the CD31 expression. In univariate analysis, patients with tumours in the quartile with the highest expression had a more favourable prognosis (p = 0.01) compared to those with lower CD31 expression. A multivariate analysis of prognostic factors in conventional RCC showed that TNM stage and nuclear grade were independent predictors of prognosis, but CD31 expression did not add further prognostic information.

Angiogenesis and other markers for prediction of survival in metastatic renal cell carcinoma

OBJECTIVE

The treatment of metastatic renal cell carcinoma (RCC) remains a clinical challenge. Factors predicting any benefit of different therapies would therefore be useful. Angiogenesis is important in tumor progression and the development of metastases. The aim of this study in patients with distant metastases at diagnosis was to evaluate possible outcome information obtained with a number of soluble angiogenic variables in serum.

MATERIAL AND METHODS

Serum samples were taken at diagnosis from 120 consecutive patients with metastatic RCC who were operated on with radical nephrectomy. Different clinicopathological variables and vascular endothelial growth factor (VEGF), vascular endothelial growth factor receptor-1 (VEGFR-1), basic fibroblast growth factor (bFGF) and erythropoietin levels in serum were compared with the clinical course.

RESULTS

The median survival time for all patients was 9 months. Six patients (5%) died during the postoperative period, all of whom had a performance status (PS) of 2 or 3. None of the angiogenic factors (VEGF, VEGFR-1, bFGF, erythropoietin) gave any prognostic information, except that VEGF was associated with survival (p = 0.0234) in patients with a good PS. A number of other variables gave prognostic information in univariate analysis but, after multivariate analysis, only PS (p = 0.002), the number of metastatic sites (p = 0.003) and capsule invasion (p = 0.017) remained as independent predictive factors.

CONCLUSIONS

Among predictive factors, only PS, the number of metastatic sites and capsule invasion independently predicted survival in patients with metastatic RCC, while soluble angiogenic factors in serum gave no prognostic information. Nephrectomy in patients with metastatic RCC remains controversial but long-term survival can be achieved in selected patients, especially those with a good PS.

Insulin-like Growth Factor I in Pregnancy and Maternal Risk of Breast Cancer

BACKGROUND

The role of insulin-like growth factor (IGF)-I in breast cancer remains controversial, despite numerous reports on the association of the hormone with breast cancer or high-risk mammographic densities. We hypothesized that exposure to elevated IGF-I during early pregnancy, a period characterized by intense cell proliferation in the breasts and in the presence of high concentrations of sex steroids, will be associated with increased maternal risk to develop a breast malignancy.

METHODS

The Northern Sweden Maternity Cohort is an ongoing prospective study, collecting blood samples from first-trimester-pregnant women since 1975 as part of screening for infectious diseases. A case-control study (212 cases and 369 controls) was nested among Northern Sweden Maternity Cohort members who delivered singleton babies. RIA was used to measure IGF-I and IGF-II levels. Conditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI).

RESULTS

Breast cancer risk increased with increasing IGF-I (top tertile OR, 1.7; 95% CI, 1.1-2.7). The association was stronger among the primiparous (OR, 2.2; 95% CI, 1.1-4.4) than in the nonprimiparous women (OR, 1.4; 95% CI, 0.7-2.8). Upper-tertile risks seemed to decrease within the <28-, 28 to 33, and >33-year groups of age at sampling, from 2.5 (0.9-7.6) to 2.1 (0.9-5.0) and 1.2 (0.5-2.5), respectively. There was no association of breast cancer with first-trimester-pregnancy IGF-II.

CONCLUSIONS

The study offers further evidence that IGF-I is important in breast cancer. Our findings suggest that the adverse effect of IGF-I on the breast may be stronger before the remodeling of the gland induced by a first pregnancy.

Induction of apoptosis by intracellular potassium ion depletion: Using the fluorescent dye PBFI in a 96-well plate method in cultured lung cancer cells

Depletion of intracellular potassium ions (K+) is necessary for cells to shrink, activate caspases and induce DNA fragmentation, events which are features of apoptosis. Here we describe a 96-well plate method using the cell permeable form of K+ binding benzofuran isophtalate (PBFI-AM) to measure intracellular K+ content in relation to untreated control. Cultured human pulmonary mesothelioma cells (P31) and small-cell lung cancer cells (U1690) were treated with K+ flux modulators in order to deprive the cells of intracellular K+. The combination of K+ influx inhibition with 10 micromol/L bumetanide plus 10 micromol/L ouabain and K+ efflux stimulation with 3 mg/L amphotericin B or 5 micromol/L nigericin efficiently reduced the intracellular K+ content after 3 h. Manipulation of K+ fluxes with subsequent intracellular K+ depletion induced apoptosis of lung cancer cells, as detected by caspase-3 activity after 3 h K+ depletion followed by 24 h proliferation and TUNEL positive staining after 48 h proliferation. We concluded that the PBFI-AM assay was a useful tool to determine intracellular K+ content in relation to untreated control, and that intracellular K+ depletion of lung cancer cells by clinically used drugs of relevant concentrations induced apoptosis. These findings may lead to novel therapeutic strategies in the treatment of lung cancer.

Different vascular endothelial growth factor (VEGF), VEGF-receptor 1 and -2 mRNA expression profiles between clear cell and papillary renal cell carcinoma

OBJECTIVES

To examine vascular endothelial growth factor (VEGF), VEGF-receptor-(R)1, and R2 mRNA levels in renal cell carcinoma (RCC), a tumour generally refractory to most medical therapy, but for which a potentially useful therapeutic alternative is inhibition of angiogenesis.

PATIENTS AND METHODS

VEGF, VEGF-R1 and -R2 mRNA levels were analysed using the quantitative reverse transcription-polymerase chain reaction. RNA was extracted from 84 conventional (clear cell) RCCs (cRCC), 20 papillary (pRCC), six chromophobe (chRCC), and 27 corresponding kidney cortex tissues, obtained from 110 patients in whom high-quality RNA was available from the tumours (53 women and 57 men, mean age 64.7 years, range 25-85).

RESULTS

The VEGF, VEGF-R1, and -R2 mRNA levels were higher in tumour than in kidney cortex tissues. Among the RCC types, cRCC had higher VEGF levels than pRCC. In cRCC, VEGF-R2 levels were higher in stage I-II than in more advanced stages. In pRCC, VEGF and VEGF-R2 levels were higher in stage III than in stage I-II tumours. In cRCC, patients with VEGF levels below the median had a significantly shorter survival time than those with higher levels. By contrast, in pRCC, VEGF, VEGF-R1 and -R2 RNA levels above the median were related to adverse survival. Using multivariate analysis in cRCCs, VEGF-R1 mRNA level was the last factor to be omitted after stepwise elimination analysis.

CONCLUSION

VEGF and its receptors were associated with tumour stage and survival, but were not independent prognostic factors. Different RCC types had different expression patterns of VEGF and receptor mRNA levels. We conclude that different pathways might be involved in regulating angiogenesis in the specific RCC types. Detailed knowledge of angiogenesis in RCC is essential when designing new treatment trials where angiogenesis inhibition is used.

Hypoxia-inducible factor 1alpha expression in renal cell carcinoma analyzed by tissue microarray

OBJECTIVES

Angiogenesis is important for tumour progression and metastatic spread. Hypoxia-inducible factor 1alpha (HIF-1alpha) is a major factor regulating a number of other angiogenic factors. Renal cell carcinoma (RCC) is a malignancy with a variable clinical course, partly attributable to specific genetic alterations of the different RCC types. We therefore analysed HIF-1alpha expression using immunohistochemistry and related the results to RCC type and clinicopathologic variables.

MATERIAL AND METHODS

We semiquantitatively analysed HIF-1alpha expression using immunohistological staining of a prepared tissue microarray. There were 216 patients including 176 conventional, 26 papillary, and 14 chromophobe RCCs.

RESULTS

The HIF-1alpha staining was found mainly in the cytoplasm. The tumours were subdivided into HIF-1alpha(LOW) and HIF-1alpha(HIGH) on the basis of staining intensity. HIF-1alpha expression between the RCC types did not differ. Patients with conventional RCC showed a trend (p=0.055) towards a prolonged survival for those with HIF-1alpha(HIGH)-staining versus HIF-1alpha(LOW)-staining tumors. In conventional RCC there were significant differences in HIF-1alpha expression in relation to TNM stage, nuclear grade, and vein invasion. In patients with papillary RCC, difference in HIF-1alpha expression was observed only for nuclear grade.

CONCLUSIONS

We studied HIF-1alpha expression in RCC using tissue microarray. In patients with conventional RCC, HIF-1alpha levels were significantly lower in locally aggressive tumors versus localized tumors, and patients with high HIF-1alpha levels tended to have a better prognosis. There seems to be a diverging regulation of angiogenesis between the different RCC types. Further studies of HIF and angiogenesis in RCC are encouraged.

Acquired neonatal thyroid disease due to TSH receptor antibodies in breast milk

INTRODUCTION

We investigated whether thyroid receptor antibodies (TRAb) could result in transient neonatal thyroid disease by transfer through milk from mothers treated for thyrotoxicosis.

AIM

To analyse whether breast milk content of TRAb in euthyroid mothers with treated thyrotoxicosis resulted in neonatal thyroid disease and whether extended breastfeeding prolonged the neonatal disease.

PATIENTS

We tested three TRAb-positive mothers and the course, treatment and outcome for their offspring with neonatal thyrotoxicosis, and six healthy and two TRAb-negative euthyroid mothers with treated thyrotoxicosis during breastfeeding.

METHOD

TRAb was analysed in serum and breast milk by a radioreceptor assay.

RESULTS

TRAb in serum was detectable in all treated mothers, in one mother during her four pregnancies, resulting in all neonates requiring treatment for thyrotoxicosis. Serum TRAb concentration in neonates decreased continuously with time after birth. Breast milk TRAb was detectable in all cases but not in the controls or in TRAb-negative mothers treated for thyrotoxicosis. The calculated half-life for offspring serum and breast milk TRAb was calculated as approx. 3 weeks and 2 months, respectively.

CONCLUSION

Euthyroid TRAb-positive mothers may cause transient neonatal thyroid disease which seems to be worse and more prolonged during breastfeeding as a consequence of TRAb in breast milk.

Different isoform patterns for vascular endothelial growth factor between clear cell and papillary renal cell carcinoma

OBJECTIVE

To investigate the protein expression of vascular endothelial growth factor (VEGF) isoforms in relation to the clinical course in patients with different renal cell carcinoma (RCC) types, as angiogenesis is essential for tumour growth and metastasis.

PATIENTS AND METHODS

Western blots were assayed of protein extracts from tumour and concomitant kidney cortex samples from 96 patients. The levels of VEGF189, VEGF165, and VEGF121 isoforms were correlated with clinicopathological characteristics and survival.

RESULTS

VEGF189 levels were significantly higher in kidney cortex and chromophobe RCC than in papillary and conventional RCC. In papillary RCCs, VEGF189 levels correlated inversely with tumour stage and tumour size. VEGF165 levels were higher in kidney cortex than in RCC, but there was no difference among the RCC types. VEGF121 expression was associated with less advanced tumour stage in conventional RCC. Using multivariate analysis, VEGF189 remained as an independent prognostic factor for patients with papillary RCC.

CONCLUSIONS

VEGF189 was associated with tumour progression; in papillary RCC, VEGF189 was a significant independent prognostic factor. VEGF protein isoform patterns differed among the specific RCC types. Additional knowledge is essential to design new anti-angiogenic therapies for all RCC types.

Adenylate cyclase toxin from Bordetella pertussis enhances cisplatin-induced apoptosis to lung cancer cells in vitro

The present study examined the possibility to enhance lung cancer cell cytotoxicity and apoptosis of the anticancer drug cisplatin by exposure with adenylate cyclase (AC) toxin from Bordetella pertussis. A malignant mesothelioma cell line (P31) and a small-cell lung cancer cell line (U1690) were exposed to increasing concentrations of cisplatin and AC toxin, alone or in combination. Cytotoxicity was determined by a fluorescein-based assay and apoptosis by flow cytometry quantification of annexin V binding. Caspase-3, -8, and -9 activities were measured by enzyme activity assays. The cytotoxicity of AC toxin was time and dose dependent with an LD50 value at 72 h of 3 and 7 mg/L for P31 cells and U1690 cells, respectively. Cisplatin showed a similar time- and dose-dependent cytotoxicity, which was increased in the presence of a low toxic concentration (1 mg/L) of AC toxin. Furthermore, cisplatin caused a dose-dependent increase of annexin V binding cells of both cell lines after 24-h incubation, which was also enhanced in combination with AC toxin. AC toxin (1 mg/L) increased cisplatin-induced caspase-3, -8, and -9 activities in U1690 cells. Only minor increases of caspase-8 and -9 were noted for P31 cells. The present results, together with the knowledge that bacterial toxins decrease side effects of traditional cancer treatment, suggest a possibility to use them to enhance the therapeutic effect of cancer chemotherapy with reduced clinical adverse effects.

Endoglin (CD105) expression in human renal cell carcinoma

OBJECTIVE

To evaluate the prognostic potential of endoglin (CD105) expression in human renal cell carcinoma (RCC), as endoglin is a cell membrane glycoprotein expressed in tumour-associated vascular endothelium and a marker of angiogenesis; intratumoral microvessel density assessed by endoglin staining has prognostic significance in some neoplasms.

PATIENTS AND METHODS

Tumour samples from 210 patients with RCC (168 conventional), diagnosed between 1982 and 1997, were assessed using the tissue microarray technique with immunohistochemical staining for endoglin. The expression of endoglin was related to clinical variables and survival.

RESULTS

Of the tumours, 75% expressed endoglin, and in conventional RCC the expression was inversely correlated to the Tumour-Node-Metastasis (TNM) stage (P = 0.008) and nuclear grade (P = 0.01). There was no correlation between endoglin expression and gender, age, tumour size or cell type. Patients with conventional RCC and high endoglin expression had a more favourable prognosis than those with tumours with lower expression (P = 0.04). A multivariate analysis of prognostic factors showed that TNM stage and nuclear grade were independent predictors of prognosis. Endoglin expression did not add further prognostic information.

CONCLUSION

These results indicate that endoglin expression is inversely related to stage and grade in RCC, and that it is associated with prognosis.

Gene expression profiling predicts survival in conventional renal cell carcinoma

BACKGROUND

Conventional renal cell carcinoma (cRCC) accounts for most of the deaths due to kidney cancer. Tumor stage, grade, and patient performance status are used currently to predict survival after surgery. Our goal was to identify gene expression features, using comprehensive gene expression profiling, that correlate with survival.

METHODS AND FINDINGS

Gene expression profiles were determined in 177 primary cRCCs using DNA microarrays. Unsupervised hierarchical clustering analysis segregated cRCC into five gene expression subgroups. Expression subgroup was correlated with survival in long-term follow-up and was independent of grade, stage, and performance status. The tumors were then divided evenly into training and test sets that were balanced for grade, stage, performance status, and length of follow-up. A semisupervised learning algorithm (supervised principal components analysis) was applied to identify transcripts whose expression was associated with survival in the training set, and the performance of this gene expression-based survival predictor was assessed using the test set. With this method, we identified 259 genes that accurately predicted disease-specific survival among patients in the independent validation group (p < 0.001). In multivariate analysis, the gene expression predictor was a strong predictor of survival independent of tumor stage, grade, and performance status (p < 0.001).

CONCLUSIONS

cRCC displays molecular heterogeneity and can be separated into gene expression subgroups that correlate with survival after surgery. We have identified a set of 259 genes that predict survival after surgery independent of clinical prognostic factors.

Increased copy number at 3p14 in breast cancer

INTRODUCTION

The present study was conducted to investigate if chromosome band 3p14 is of any pathogenic significance in the malignant process of breast cancer. Genetic studies have implicated a tumour suppressor gene on chromosome arm 3p and we have proposed LRIG1 at 3p14 as a candidate tumour suppressor. The LRIG1 gene encodes an integral membrane protein that counteracts signalling by receptor tyrosine kinases belonging to the ERBB family. LRIG1 mRNA and protein are expressed in many tissues, including breast tissue.

METHODS

In the present report we analysed the LRIG1 gene by fluorescence in situ hybridisation (FISH), LRIG1 mRNA by quantitative RT-PCR, and LRIG1 protein by western blot analysis. Two tumour series were analysed; one series consisted of 19 tumour samples collected between 1987 and 1995 and the other series consisted of 9 tumour samples with corresponding non-neoplastic breast tissues collected consecutively.

RESULTS

The LRIG1 gene showed increased copy number in 11 out of 28 tumours (39%) and only one tumour showed a deletion at this locus. Increased LRIG1 copy number was associated with increased levels of LRIG1 mRNA (two of three tumours) and protein (four of four tumours) in the tumours compared to matched non-neoplastic breast tissue, as assessed by RT-PCR and western blot analysis.

CONCLUSION

The molecular function of LRIG1 as a negative regulator of ERBB receptors questions the biological significance of increased LRIG1 copy number in breast cancer. We propose that a common, but hitherto unrecognised, breast cancer linked gene is located within an amplicon containing the LRIG1 locus at 3p14.3.

Pharmacological modulation of lung cancer cells for potassium ion depletion

BACKGROUND

Depletion of intracellular potassium ions (K+) is necessary for cells to shrink, induce DNA fragmentation and activate caspases, events which are features of apoptosis.

MATERIALS AND METHODS

We used 86Rb+ as a K+ analogue to evaluate the possibility of pharmacologically depleting human pulmonary mesothelioma (P31) and small cell lung cancer (U1690) cells of K+, for future use in studies of apoptosis induction.

RESULTS

The Na+, K+, 2CI(-)-cotransport inhibitor bumetanide transiently inhibited 86Rb+ influx, but when combined with the Na+, K+, ATPase pump inhibitor ouabain there was a marked and lasting (up to 6 h) 86Rb+ influx inhibition. Cellular K+ efflux was augmented by amphotericin B, digitonin and nigericin. Amphotericin B was an effective 86Rb+ efflux stimulator with low cytotoxicity, whereas digitonin caused cell detachment and nigericin increased LDH release in the U1690 cell line, indicating considerable toxicity of the drugs.

CONCLUSION

It is possible to efficiently reduce intracellular K+ by persistent K+ influx inhibition and simultaneous K+ efflux stimulation with clinically available drugs.

The Expression of Hypoxia-Inducible Factor 1α Is a Favorable Independent Prognostic Factor in Renal Cell Carcinoma

Purpose: Renal cell carcinoma (RCC) is the most common malignancy of the kidney composed of specific tumor types. The sporadic conventional RCCs are, in contrast to the other RCC types, characterized by a high rate of von Hippel-Lindau (VHL) mutations and hypermethylation. The majority of these tumors lack functional VHL protein (pVHL) that leads to increased hypoxia-inducible factor 1α (HIF-1α) expression. The pVHL is the physiologic regulator of the activity of HIF-1α by targeting it to the proteasome for degradation under normoxia. Both pVHL and HIF-1α target other genes that are important for cancer survival and proliferation. Expression of HIF-1α has been linked to poor prognosis in different malignancies, although few studies have been done on the relation between HIF-1α and clinical variables in RCC.

Experimental Design: HIF-1α protein expression was analyzed in tumor tissue from 92 patients with RCC. HIF-1α was quantified by Western blot relative to a positive control.

Results: The HIF-1α protein was expressed as two bands which strongly correlated (r = 0.906, P &lt; 0.001); therefore, they were added and the sum evaluated against clinicopathologic variables. There was no association between HIF-1α and gender, stage, grade, tumor size, or vein invasion. Conventional RCCs had significantly higher HIF-1α expression compared with papillary and chromophobe RCCs and kidney cortex. In conventional RCC, HIF-1α was an independent prognostic factor.

Conclusion: HIF-1α levels varied significantly between the different RCC types. In conventional RCC, HIF-1α was an independent prognostic factor. These data indicate that HIF-1α is involved in tumorogenesis and progression of RCC. Evaluation of other HIF target gene products and correlation to angiogenesis seems warranted.

The expression of hypoxia-inducible factor 1alpha is a favorable independent prognostic factor in renal cell carcinoma

PURPOSE

Renal cell carcinoma (RCC) is the most common malignancy of the kidney composed of specific tumor types. The sporadic conventional RCCs are, in contrast to the other RCC types, characterized by a high rate of von Hippel-Lindau (VHL) mutations and hypermethylation. The majority of these tumors lack functional VHL protein (pVHL) that leads to increased hypoxia-inducible factor 1alpha (HIF-1alpha) expression. The pVHL is the physiologic regulator of the activity of HIF-1alpha by targeting it to the proteasome for degradation under normoxia. Both pVHL and HIF-1alpha target other genes that are important for cancer survival and proliferation. Expression of HIF-1alpha has been linked to poor prognosis in different malignancies, although few studies have been done on the relation between HIF-1alpha and clinical variables in RCC.

EXPERIMENTAL DESIGN

HIF-1alpha protein expression was analyzed in tumor tissue from 92 patients with RCC. HIF-1alpha was quantified by Western blot relative to a positive control.

RESULTS

The HIF-1alpha protein was expressed as two bands which strongly correlated (r = 0.906, P < 0.001); therefore, they were added and the sum evaluated against clinicopathologic variables. There was no association between HIF-1alpha and gender, stage, grade, tumor size, or vein invasion. Conventional RCCs had significantly higher HIF-1alpha expression compared with papillary and chromophobe RCCs and kidney cortex. In conventional RCC, HIF-1alpha was an independent prognostic factor.

CONCLUSION

HIF-1alpha levels varied significantly between the different RCC types. In conventional RCC, HIF-1alpha was an independent prognostic factor. These data indicate that HIF-1alpha is involved in tumorogenesis and progression of RCC. Evaluation of other HIF target gene products and correlation to angiogenesis seems warranted.

Parathyroid Hormone-Related Protein and Serum Calcium in Patients with Renal Cell Carcinoma

OBJECTIVE

To evaluate serum parathyroid hormone-related protein (PTHrP) in relation to serum calcium and clinical outcome of patients with renal cell carcinoma.

METHODS

Sera from 243 patients with renal cell carcinoma were collected prior to therapy. Serum PTHrP was analyzed using an immunoradiometric assay. Tumour stage, nuclear grade, corrected serum calcium, and survival were assessed.

RESULTS

Serum PTHrP was detectable in 37/243 sera (15%) and hypercalcaemia (> or =2.60 mmol/l) in 32/220 (15%). A positive correlation between serum PTHrP and serum calcium was found (r = 0.326; p < 0.01). Following subdivision of the material, based on storage time, the frequency of detectable serum PTHrP seemed to decrease with time. Serum calcium, but not serum PTHrP, was correlated to tumour stage (p < 0.001). Survival was similar for patients with detectable and undetectable PTHrP, but those with hypercalcaemia had a significantly shorter survival time compared to those with normal serum calcium (p < 0.001). A multivariate analysis showed that tumour stage and serum calcium were independent prognostic factors, but not grade or PTHrP.

CONCLUSIONS

A positive relation of serum PTHrP to serum calcium was demonstrated in patients with renal cell carcinoma. Hypercalcaemia but not serum PTHrP predicted a worse prognosis.