Serum ferritin as a clinical marker for renal cell carcinoma: influence of tumor volume

The Great Masquerader's New Wardrobe in the Modern Era: The Paraneoplastic Manifestations of Renal Cancer

Paraneoplastic syndromes can occur in 8% to 20% of individuals with malignancies. They can occur in a variety of cancers that include breast, gastric, leukemia, lung, ovarian, pancreatic, prostate, testicular, as well as kidney. The classic presentation of the triad of mass, hematuria, and flank pain occurs in less than 15% of patients with renal cancer. Because of the protean presentations of renal cell cancer, it has been referred to as the internist's tumor or the great masquerader. This article will provide a review of the causes of these symptoms.

MN/CA9 gene expression as a potential tumor marker for renal cell carcinoma

MN/CA9 is a cell surface glycoprotein and a tumor-associated antigen. It plays a crucial role in the regulation of cell proliferation and oncogenesis. There is no ideal tumor marker currently available for renal cell carcinoma (RCC) with sufficient sensitivity and specificity. Therefore, we studied MN/CA9 gene expression in the tumor tissue, apparently normal kidney tissue, preoperative blood, and urine samples of patients with RCC. We included thirty cases of renal tumors (26 RCC and 4 benign tumors) in the study. We applied an RT-PCR assay for MN/CA9 gene expression to 26 RCC kidney tumor samples and four benign kidney tumor tissue samples. We also evaluated MN/CA9 gene expression in preoperative blood and urine samples of 15 of these cases. Additionally, thirty-five grossly normal renal tissue samples, including 21 from kidneys with RCC, were also evaluated for gene expression. The RT-PCR analysis revealed that twenty-one out of 26 RCC tissue samples showed MN/CA9 gene expression compared to three out of 35 non-malignant renal tissue samples (p < 0.05). Two out of four benign renal tissue samples also expressed this gene. We also observed MN/CA9 gene expression in nine out of 15 blood samples and four out of 15 urine samples. All patients with urinary MN/CA9 gene expression showed expression in blood and tumor tissue samples. We found a correlation in terms of MN/CA9 expression between blood and tumor tissue samples of RCC patients as those who exhibit MN/CA9 expression in blood were also positive at the tumor tissue levels. The difference in MN/CA9 gene expression in tumor tissue, blood, and urine samples in relation to the stage of the disease, nuclear grade, and histological cell-type was not statistically significant. However, all the three patients who had metastatic RCC had MN/CA9 gene expression in their blood. The existence of a tumor-associated antigen such as MN/CA9 may present a possible target for molecular diagnosis and management of RCC.

Quantitative ultrasound elastography and serum ferritin level in dogs with liver tumors

Objective:

The objective of this study was to assess the serum ferritin level and quantitate ultrasound elastography as a marker to distinguish dogs with benign and malignant liver tumors.

Materials and Methods:

Twenty-eight dogs were determined the serum ferritin and ultrasound elastography by using fine-needle aspiration biopsy.

Results:

Our results demonstrated that dogs with malignant liver tumors had significantly higher mean serum ferritin concentrations than those with benign liver tumors (p = 0.004). The mean intensity of blue and red colors from elastography was greater in the malignant than those in the benign group, especially for the blue color, meaning that lesions showed more hard tissue. Additionally, histograms of blue color in the malignant tended to be higher than the benign group.

Conclusion:

We suggested that quantitative ultrasound elastography and serum ferritin concentration comprise an alternative and non-invasive diagnostic method that could be used to predict the type of liver tumors in dogs.

Yeast extract inhibits the proliferation of renal cell carcinoma cells via regulation of iron metabolism

The microbiome has recently attracted research interest in a variety of subjects, including cancer. In the present study, it was determined that reinforced clostridium media (RCM) for microbiome culture, exerts antitumor effects on renal cell carcinoma cells when compared to the microbiome 'X'. The antitumor effects of RCM were investigated for all ingredients of RCM, and the results revealed that yeast extract could be a candidate for the ingredient driving this phenomenon. Further experiments including MTT assay, cell counting, cell death analysis, cell cycle analysis and western blotting were conducted with yeast extract on renal cell carcinoma cells (Caki‑1 and Caki‑2) and normal human proximal tubular cells (HK‑2). As a result, yeast extract exhibited dose‑dependent antitumor effects on Caki‑1 and Caki‑2, but only slight effects on HK‑2. In addition, yeast extract only exhibited slight effects on necrosis, autophagy, or apoptosis of Caki‑1 and Caki‑2. Yeast extract produced cell cycle arrest with an increased G0/G1 fraction and a decreased S fraction, and this was considered to be related to the decreased cyclin D1. Although yeast extract treatment increased anti‑oxidant activities, the antitumor effects of yeast extract were also related to iron metabolism, based on the decreased transferrin receptor and increased ferritin. In addition, decreased GPX4 may be related to iron‑dependent cell death, particularly in Caki‑2. These results revealed that yeast extract may inhibit proliferation of renal cell carcinoma cells by regulating iron metabolism. Since an increased iron requirement is a classic phenomenon of cancer cells, yeast extract may be a candidate for adjuvant treatment of renal cell carcinoma.

Methods for the evaluation of biomarkers in patients with kidney and liver diseases: multicentre research programme including ELUCIDATE RCT

Background

Protein biomarkers with associations with the activity and outcomes of diseases are being identified by modern proteomic technologies. They may be simple, accessible, cheap and safe tests that can inform diagnosis, prognosis, treatment selection, monitoring of disease activity and therapy and may substitute for complex, invasive and expensive tests. However, their potential is not yet being realised.

Design and methods

The study consisted of three workstreams to create a framework for research: workstream 1, methodology – to define current practice and explore methodology innovations for biomarkers for monitoring disease; workstream 2, clinical translation – to create a framework of research practice, high-quality samples and related clinical data to evaluate the validity and clinical utility of protein biomarkers; and workstream 3, the ELF to Uncover Cirrhosis as an Indication for Diagnosis and Action for Treatable Event (ELUCIDATE) randomised controlled trial (RCT) – an exemplar RCT of an established test, the ADVIA Centaur® Enhanced Liver Fibrosis (ELF) test (Siemens Healthcare Diagnostics Ltd, Camberley, UK) [consisting of a panel of three markers – (1) serum hyaluronic acid, (2) amino-terminal propeptide of type III procollagen and (3) tissue inhibitor of metalloproteinase 1], for liver cirrhosis to determine its impact on diagnostic timing and the management of cirrhosis and the process of care and improving outcomes.

Results

The methodology workstream evaluated the quality of recommendations for using prostate-specific antigen to monitor patients, systematically reviewed RCTs of monitoring strategies and reviewed the monitoring biomarker literature and how monitoring can have an impact on outcomes. Simulation studies were conducted to evaluate monitoring and improve the merits of health care. The monitoring biomarker literature is modest and robust conclusions are infrequent. We recommend improvements in research practice. Patients strongly endorsed the need for robust and conclusive research in this area. The clinical translation workstream focused on analytical and clinical validity. Cohorts were established for renal cell carcinoma (RCC) and renal transplantation (RT), with samples and patient data from multiple centres, as a rapid-access resource to evaluate the validity of biomarkers. Candidate biomarkers for RCC and RT were identified from the literature and their quality was evaluated and selected biomarkers were prioritised. The duration of follow-up was a limitation but biomarkers were identified that may be taken forward for clinical utility. In the third workstream, the ELUCIDATE trial registered 1303 patients and randomised 878 patients out of a target of 1000. The trial started late and recruited slowly initially but ultimately recruited with good statistical power to answer the key questions. ELF monitoring altered the patient process of care and may show benefits from the early introduction of interventions with further follow-up. The ELUCIDATE trial was an ‘exemplar’ trial that has demonstrated the challenges of evaluating biomarker strategies in ‘end-to-end’ RCTs and will inform future study designs.

Conclusions

The limitations in the programme were principally that, during the collection and curation of the cohorts of patients with RCC and RT, the pace of discovery of new biomarkers in commercial and non-commercial research was slower than anticipated and so conclusive evaluations using the cohorts are few; however, access to the cohorts will be sustained for future new biomarkers. The ELUCIDATE trial was slow to start and recruit to, with a late surge of recruitment, and so final conclusions about the impact of the ELF test on long-term outcomes await further follow-up. The findings from the three workstreams were used to synthesise a strategy and framework for future biomarker evaluations incorporating innovations in study design, health economics and health informatics.

Trial registration

Current Controlled Trials ISRCTN74815110, UKCRN ID 9954 and UKCRN ID 11930.

Funding

This project was funded by the NIHR Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 6, No. 3. See the NIHR Journals Library website for further project information.

Serum CA125 in combination with ferritin improves diagnostic accuracy for epithelial ovarian cancer

INTRODUCTION

CA125 has poor sensitivity and low specificity for detecting early ovarian cancer. Serum ferritin is elevated in many malignancies. We evaluated the performance of ferritin alone and in combination with CA125 as a diagnostic tool to detect epithelial ovarian cancer (EOC).

METHODS

CA125 and ferritin were detected in the serum of 50 healthy control (HC), 50 women with benign gynaecological conditions and 124 women with EOC. The relationship between serum ferritin and CA125 and each of the clinicopathological parameters was assessed, and their diagnostic accuracy for discriminating ovarian cancer determined.

RESULTS

Serum ferritin and CA125 were higher in patients with EOC compared to HCs and patients with benign conditions (both p < 0.001). There was no relationship between levels of ferritin and CA125. Both ferritin and CA125 discriminated HC from EOC (p < 0.05), but ferritin showed better diagnostic accuracy than CA125 (p = 0.048). Ferritin was superior to CA125 in discrimination early EOC (p = 0.002), but in advanced stages, CA125 was superior (p = 0.026). A combination of ferritin and CA125 marginally increases the diagnostic accuracy to discriminate EOC from HCs.

CONCLUSION

Ferritin discriminates between HCs and EOC patients, especially in early stage disease. The combination of serum ferritin and CA125 provides the higher diagnostic accuracy to screen for EOC. Serum ferritin could serve as an EOC biomarker to complement the standard CA125 test.

Serum Ferritin in Colorectal Cancer Patients and its Prognostic Evaluation

The aim of this study was to investigate the relationship between preoperative serum ferritin levels, clinicopathological parameters and survival analysis of patients with colorectal cancer. Ninety-four patients (57 males) with a mean age of 65 years (39–87 years) underwent 63 curative and 31 palliative operations. Follow-up was at least 5 years. Patients were categorized with normal (30-215 ng/mL in men and 11-148 ng/mL in women), low, or high serum ferritin levels. Prognostic evaluation was undertaken with stratified survival analysis and Cox's regression model. Twenty-nine of the patients (30.9%) had raised ferritin levels and 14 (14.9%) had low values. Comparisons of the survival curves showed significant differences in stage C disease; specifically, patients with either low or high ferritin levels had a shorter survival than patients with normal levels. Patients who underwent palliative surgery and had high ferritin serum values also had a shorter survival. In multivariate analysis, the variables with a negative effect on survival were stage, serum ferritin levels and age. Our data suggest that patients with advanced colorectal cancer having normal preoperative serum ferritin levels may have a better prognosis, although the prognostic value related to this association requires further investigation.

Serum ferritin in combination with prostate-specific antigen improves predictive accuracy for prostate cancer

Ferritin is highly expressed in many cancer types. Although a few studies have reported an association between high serum ferritin levels and an increased risk of prostate cancer, the results are inconsistent. Therefore, we performed a large case-control study consisting of 2002 prostate cancer patients and 951 control patients with benign prostatic hyperplasia (BPH). We found that high ferritin levels were positively associated with increased serum prostate-specific antigen (PSA) levels and prostate cancer risk; each 100 ng/ml increase in serum ferritin increased the odds ratio (OR) by 1.20 (95% CI: 1.13−1.36). In the prostate cancer group, increased serum ferritin levels were significantly correlated with higher Gleason scores (p < 0.001). Notably, serum PSA values had even higher predictive accuracy among prostate cancer patients with serum ferritin levels > 400 ng/ml (Gleason score + total PSA correlation: r = 0.38; Gleason score + free PSA correlation: r = 0.49). Moreover, using immunohistochemistry, we found that prostate tissue ferritin levels were significantly higher (p < 0.001) in prostate cancer patients (n = 129) compared to BPH controls (n = 31). Prostate tissue ferritin levels were also highly correlated with serum ferritin when patients were classified by cancer severity (r = 0.81). Importantly, we found no correlation between serum ferritin levels and the inflammation marker C-reactive protein (CRP) in prostate cancer patients. In conclusion, serum ferritin is significantly associated with prostate cancer and may serve as a non-invasive biomarker to complement the PSA test in the diagnosis and prognostic evaluation of prostate cancer.

Clinical significance of preoperative thrombocytosis in patients who underwent radical nephrectomy for nonmetastatic renal cell carcinoma

Purpose

The aim of this study was to examine the association of preoperative thrombocytosis with the prognosis of patients with nonmetastatic renal cell carcinoma (RCC).

Materials and Methods

We conducted a retrospective analysis of 187 patients who underwent a radical nephrectomy for nonmetastatic RCC between July 1997 and June 2009. Thrombocytosis was defined as a platelet count≥400,000 µL, and patients were divided into 2 groups according to presence of preoperative thrombocytosis, and the cancer-specific survival rates and overall survival rates of the 2 groups after radical nephrectomy were compared.

Results

The mean age of the patients was 56.0±11.7 years and the mean follow-up period was 59.3±42.1 months; there were 20 patients with preoperative thrombocytosis. Thirty patients developed metastases and 9 patients died during the follow-up period. In Kaplan-Meier analysis using a univariate log-rank test, both cancer-specific survival rate (p=0.013) and overall survival rate (p=0.012) showed significant association with preoperative thrombocytosis. Controlling for pathological TNM stage, Fuhrman grade and tumor diameter, the Cox proportional hazards model for cancer-specific survival rates showed that preoperative thrombocytosis was an independent prognostic factor (p=0.025).

Conclusions

Preoperative thrombocytosis was associated with poorer prognosis in patients with nonmetastatic RCC. Thus, preoperative platelet count may be clinically useful for risk stratification of patients undergoing surgery for nonmetastatic RCC.

The significance of ferritin in cancer: anti-oxidation, inflammation and tumorigenesis

The iron storage protein ferritin has been continuously studied for over 70years and its function as the primary iron storage protein in cells is well established. Although the intracellular functions of ferritin are for the most part well-characterized, the significance of serum (extracellular) ferritin in human biology is poorly understood. Recently, several lines of evidence have demonstrated that ferritin is a multi-functional protein with possible roles in proliferation, angiogenesis, immunosuppression, and iron delivery. In the context of cancer, ferritin is detected at higher levels in the sera of many cancer patients, and the higher levels correlate with aggressive disease and poor clinical outcome. Furthermore, ferritin is highly expressed in tumor-associated macrophages which have been recently recognized as having critical roles in tumor progression and therapy resistance. These characteristics suggest ferritin could be an attractive target for cancer therapy because its down-regulation could disrupt the supportive tumor microenvironment, kill cancer cells, and increase sensitivity to chemotherapy. In this review, we provide an overview of the current knowledge on the function and regulation of ferritin. Moreover, we examine the literature on ferritin's contributions to tumor progression and therapy resistance, in addition to its therapeutic potential.

Ferritin stimulates breast cancer cells through an iron-independent mechanism and is localized within tumor-associated macrophages

Tumor-associated macrophages play a critical role in breast tumor progression; however, it is still unclear what effector molecular mechanisms they employ to impact tumorigenesis. Ferritin is the primary intracellular iron storage protein and is also abundant in circulation. In breast cancer patients, ferritin is detected at higher levels in both serum and tumor lysates, and its increase correlates with poor clinical outcome. In this study, we comprehensively examined the distribution of ferritin in normal and malignant breast tissue at different stages in tumor development. Decreased ferritin expression in cancer cells but increased infiltration of ferritin-rich CD68-positive macrophages was observed with increased tumor histological grade. Interestingly, ferritin stained within the stroma surrounding tumors suggesting local release within the breast. In cell culture, macrophages, but not breast cancer cells, were capable of ferritin secretion, and this secretion was further increased in response to pro-inflammatory cytokines. We next examined the possible functional significance of extracellular ferritin in a breast cancer cell culture model. Ferritin stimulated the proliferation of the epithelial breast cancer cell lines MCF7 and T47D. Moreover, this proliferative effect was independent of the iron content of ferritin and did not increase intracellular iron levels in cancer cells indicating a novel iron-independent function for this protein. Together, these findings suggest that the release of ferritin by infiltrating macrophages in breast tumors may represent an inflammatory effector mechanism by which ferritin directly stimulates tumorigenesis.

Clinical Significance of Platelet Count in Patients with Renal Cell Carcinoma

INTRODUCTION

During the last decades numerous prognostic factors have been studied for predicting survival of renal cell carcinoma (RCC). Platelet count has previously been reported to correlate with prognosis in RCC. The aim of the this study was to evaluate the significance of thrombocytosis in determining prognosis in patients with localized RCC who underwent radical nephrectomy.

PATIENTS AND METHODS

The study included 118 consecutive patients. Patients were divided into a normal platelet count group (group 1) and a thrombocytosis group (group 2) according to the preoperative platelet count. Thrombocytosis was defined as a platelet count greater than 400,000/microl. The data about stage distribution, grade, tumor size, histological subtype, hemoglobin level, Body Mass Index (BMI), age, ECOG score, gender, and survival rate of tumors between these two groups were compared. Survival estimates were compared with the Kaplan-Meier method and multivariate analysis was performed using a Cox model.

RESULTS

The mean age of the patients was 61.4 years (range 30-78), and the mean follow-up period was 52.7 +/- 19.6 months (range 9-96). Thrombocytosis was present in 23 patients (19.49%). Fourteen (60.86%) of 23 patients with thrombocytosis died of disease progression. Patients with thrombocytosis had a worse prognosis than patients without thrombocytosis (p = 0.001). Thrombocytosis was noted in 8 (10.81%) of 74 patients with stage pT1-pT2 disease and in 15 (34.09%) of 44 patients with stage pT3-pT4 disease (p = 0.004). In univariate analysis, platelet count was correlated with T stage, hemoglobin level, lymph node positivity, ECOG score, and tumor size. Controlling for established prognostic indicators of pathologic stage, tumor size, platelet count, and lymph positivity using Cox's regression test, the difference in survival between the groups remained significant (p < 0.05).

CONCLUSION

The platelet count can be considered a useful prognostic factor in patients with RCC who undergo radical nephrectomy.

Immunosuppressive acidic protein detects high nuclear grade localized renal cell carcinoma

OBJECTIVES

To identify a potentially useful preoperative predictor of high nuclear grade renal cell carcinoma (RCC).

METHODS

Our investigation consisted of 181 patients with histologically confirmed clear cell RCC. The positive predictive value, sensitivity, and specificity for detecting nuclear grade RCC were calculated individually for the largest tumor diameter. Hemoglobin, alkaline phosphatase, C-reactive protein, ferritin, and immunosuppressive acidic protein (IAP) levels were also determined in all patients preoperatively.

RESULTS

The distribution of patients by nuclear grade was 74 patients (41%) with grade 1, 75 (41%) with grade 2, and 32 (18%) with grades 3 and 4. With respect to sensitivity, tumor diameter detected 28 (87.5%) of 32 high nuclear grade RCC specimens, and hemoglobin, C-reactive protein, alkaline phosphatase, ferritin, and IAP detected 10 (31.2%), 25 (78.1%), 8 (25.0%), 16 (50%), and 27 (84.3%) of 32, respectively. Multiple logistic regression analysis showed that a higher than normal C-reactive protein and IAP was associated with a 252% and 405% increase in the odds of a high nuclear grade, respectively. In the Stage T1 cases, elevated IAP was also associated with a 989% increase in the odds of a high nuclear grade.

CONCLUSIONS

IAP level may be a useful predictor for detecting high nuclear grade localized RCC preoperatively.

Utilidad de marcadores séricos del carcinoma renal

OBJECTIVES

To select a group of useful serum markers in renal cell carcinoma (RCC) with investigational purpose in future.

MATERIAL AND METHODS

Periodic determination in serum of 21 RCC patients of the following markers: EGR, RPC, hemogram and leucocyte differential count (LDC), standard biochemist parameters, beta-2 microglobuline, CEA, CA 12.5, CA 50, CA 15.3, ferritin, interleukin-6, serum interleukin-2 receptor, TNF-alpha and TPSA.

RESULTS

Different elements within the LDC had relations with the presence of symptoms/signs, tumour size, pathological stage and disease progression. There was a significant increase of beta-2 microglobuline and sIL-2 receptor when disease progressed, as well as a similar statistical trend with RPC and alkaline phosphatases. Beta-2 microglobuline and sIL-2 receptor also decreased after treatment of the disease progression.

CONCLUSIONS

We will keep analysing hemogram, LDC and standard byochemics, RPC, ferritin, beta-2 microglobuline and sIL-2 receptor only with investigational purposes, obviating the determination of the rest of the tested markers.

Reliability of serum iron, ferritin, nitrite, and association with risk of renal cancer in women

Reliability of serum levels of iron, ferritin and nitrite (NO(2)(-)) over a 2-year period were evaluated in 40 healthy women (20 pre-menopausal and 20 post-menopausal), ages 39-65 years, from the New York University Women's Health Study (NYUWHS). Three blood samples per woman collected at yearly intervals were analyzed. Reliability coefficients (RCs) of serum iron, ferritin, and nitrite were 0.03 (95% confidence interval (CI), 0-0.33), 0.90 (95% CI, 0.79-0.95), and 0.72 (95% CI, 0.50-0.86), respectively, for pre-menopausal women, and 0.26 (95% CI, 0-0.56), 0.77 (95% CI, 0.59-0.89), and 0.55 (95% CI, 0.30-0.77), respectively, for post-menopausal women. In a case-control study nested within NYUWHS cohort, serum levels of nitrite, ferritin, and iron were measured in women apparently healthy at the time of blood donation but diagnosed with renal cancer 1.8-12.2 years later (n=24) and in individually matched controls (two per case). The results suggest that high serum levels of ferritin and nitrite may be associated with a decreased risk of renal cancer (odds ratio (OR), 0.55, 95% CI, 0.15-2.01 for ferritin, and OR, 0.52, 95% CI, 0.17-1.60 for nitrite in women with above median level as compared to women with below median level). The possible role of ferritin and nitrite in renal cancer is discussed.

Trace elements distribution in renal cell carcinoma depending on stage of disease

OBJECTIVES

The aim of this study was to identify those trace elements which can be used to distinguish between normal and malignant tissue in renal cell cancer (RCC) kidney and to assess changes in trace elements concentration in tissue with progressing malignant disease.

METHODS

In case control study, 36 cases of RCC were analyzed by Synchrotron Radiation Induced X-ray Emission (SRIXE) in order to establish the concentration of 19 elements. Patients with RCC were examined to obtain staging of disease after radical nephrectomy, which was performed in each case. Results were compared with 15 control kidney cortex tissue obtained during autopsy in which cause of death was trauma.

RESULTS

The most relevant decrease was detected in Cd content: from 81 +/- 39.2 ppm in normal control samples to 16.6 +/- 22.2 ppm concentration in RCC. We found that the concentrations of Ti, Pb and Rb were also lower in RCC tissue. On the other hand, the RCC tissue was rich in iron and zirconium. With the progress of malignant disease, assessed by TNM (UICC 1997) scale, lower concentration of S and higher concentration of Ca in both RCC and neoplastic kidney cortex can be seen. The same tendency is observed in Zn and Se concentrations. Cadmium shows raising concentration with progress of RCC only in cortex of neoplastic kidney. In all cases it was shown that the relatively high tissue concentration of iron in both investigated tissues is decreasing with the progress of disease. The zirconium has shown raising tissue concentration in advanced disease.

CONCLUSION

Trace elements concentration is different in malignant tissue and surrounding macroscopically unchanged kidney cortex. Progress of the disease is connected with changes in trace elements concentration. This may reflect different biology of compared tissue with potential practical implication.

Relationship between serum ferritin levels and tumour status in patients with renal cell carcinoma

OBJECTIVE

To assess the relationship between serum ferritin levels (a useful marker for diagnosing and staging renal cell carcinoma, RCC) and tumour status in RCC of <or=7 cm diameter.

PATIENTS AND METHODS

Serum ferritin levels were measured using an enzyme immunoassay in 101 patients before treatment for RCC. The largest diameter of the primary tumour was measured in the pathological specimens. The correlation between serum ferritin levels and histopathological status was assessed retrospectively in all patients, and separately in the 67 patients with tumours of <or=7 cm diameter.

RESULTS

For the whole group, lymph node metastasis, distant metastasis, extracapsular invasion, vascular invasion and nuclear grade were significantly different (P < 0.001) between patients with normal and those with elevated ferritin levels. However, in patients with tumours of <or=7 cm, only the presence of distant metastasis was significantly different (P < 0.001) between the groups.

CONCLUSIONS

Elevated serum ferritin levels in patients with RCC of <or=7 cm may suggest the presence of distant metastasis.

Predictive values of acute phase reactants, basic fetoprotein, and immunosuppressive acidic protein for staging and survival in renal cell carcinoma

OBJECTIVES

To determine the clinical significance and predictive value of three acute phase reactants (erythrocyte sedimentation rate, C-reactive protein, and ferritin), as well as basic fetoprotein (BFP) and immunosuppressive acidic protein, in patients with renal cell carcinoma.

METHODS

Erythrocyte sedimentation rate, C-reactive protein, ferritin, BFP, and immunosuppressive acidic protein levels were measured in 92 patients with renal cell carcinoma diagnosed in 1989 to 1999. The levels were compared with the clinical stage and nuclear grade, and their predictive values of survival were evaluated statistically.

RESULTS

All markers, with the exception of BFP, correlated with each other and with the clinical stage and nuclear grade. BFP did not correlate with the acute phase reactants. The log-rank test revealed that the levels of C-reactive protein, immunosuppressive acidic protein, and ferritin significantly influenced survival. Multivariate stepwise analysis identified ferritin as the only independent and significant prognostic marker (hazard ratio = 5.624, P = 0.001). However, when age, sex, clinical stage, and nuclear grade were entered into the same analysis, only clinical stage was an independent marker of prognosis.

CONCLUSIONS

The results of our study demonstrated that serum ferritin is the most useful marker among five tested factors for staging and predicting survival, although the clinical stage is the best parameter that predicts the prognosis of patients with renal cell carcinoma accurately.

Immunosuppressive effects of melanoma-derived heavy-chain ferritin are dependent on stimulation of IL-10 production

Cultured melanoma cells release soluble factors that influence immune responses. Screening of a cDNA library with anti-sera from a melanoma patient identified an immunoreactive plaque, which encoded heavy-chain ferritin (H-ferritin). Previous studies have drawn attention to the immunosuppressive effects of this molecule and prompted further studies on its biochemical and functional properties in human melanoma. These studies demonstrated, firstly, that H-ferritin appeared to be secreted by melanoma cells, as shown by immunoprecipitation of a 21.5 kDa band from supernatants. It was also detected in extracts of melanoma cells by Western blotting as 43 and 64 kDa dimers and trimers of the 21.5 kDa fraction. Secondly, flow-cytometric analysis of H- and light-chain ferritin (L-ferritin) expression on melanoma showed a wide variation in L-ferritin expression and consequently of the ratio of H- to L-ferritin expression. Suppression of mitogenic responses of lymphocytes to anti-CD3 showed a correlation with the ratio of H- to L-ferritin in the supernatants and was specific for H-ferritin, as shown by inhibition studies with a monoclonal antibody (MAb) against H-ferritin. Similar results were obtained with H- and L-ferritin from other sources. Suppression of mitogenic responses of lymphocytes to anti-CD3 by H-ferritin was inhibited using a MAb against IL-10, which suggested that the immunosuppressive effect of H-ferritin was mediated by IL-10. Assays of cytokine production from anti-CD3-stimulated lymphocytes showed that H-ferritin markedly increased production of IL-10 and IFN-gamma and had only slight effects on IL-2 and IL-4 production. Our results suggest that melanoma cells may be a major source of H-ferritin and that production of the latter may account for some of the immunosuppressive effects of melanoma.

The detection of renal carcinoma cells in the peripheral blood with an enhanced reverse transcriptase-polymerase chain reaction assay for MN/CA9

BACKGROUND

Using a reverse transcriptase-polymerase chain reaction (RT-PCR) assay, the authors previously determined the expression of MN/CA9 mRNA in renal cell carcinoma (RCC) and its absence in benign renal tissue. In the current study, the utility of an enhanced RT-PCR assay in the detection of renal carcinoma cells in the peripheral blood was assessed.

METHODS

An enhanced MN/CA9 RT-PCR assay was applied to peripheral blood samples from a total of 96 patients. Forty-two patients had renal tumors, including 5 with benign renal lesions, 28 with localized RCC, and 9 with metastatic RCC. Fifty-four control patients without renal tumors were similarly tested. Pathologic staging for patients with localized cancer was T1N0M0 for 5, T2N0M0 for 9, and T3N0M0 for 14 patients.

RESULTS

Cells expressing MN/CA9 were detected in 1 of 54 controls (1.8%) and in 18 of 37 cancer patients (49%). Thirteen of twenty eight patients (46%) with localized RCC and 5 of 9 (56%) with metastatic disease tested positive with the assay. No patient with a benign renal tumor exhibited MN/CA9 expression. All blood test results for patients with clear cell RCC were noted to be positive. No correlation was noted between MN/CA9 results and age, gender, or tumor grade. The differences in MN/CA9 results according to T classification were not statistically significant.

CONCLUSIONS

The enhanced RT-PCR assay for MN/CA9 is a highly specific technique for detecting circulating renal carcinoma cells in the peripheral blood, and it may prove useful in the diagnosis and monitoring of RCC.

MN/CA9 gene expression as a potential biomarker in renal cell carcinoma

OBJECTIVE

To compare the levels of MN/CA9 expression with clinicopathological variables in renal cell carcinoma (RCC), and thus evaluate MN/CA9 expression as a possible biomarker for RCC.

MATERIALS AND METHODS

The level of expression of MN/CA9 was evaluated in 76 surgically obtained tissue samples (49 from RCC, 22 from normal kidney and five from oncocytoma) using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) analysis. In RCC, MN/CA9 expression was compared with stage, grade and cell type.

RESULTS

MN/CA9 was expressed in 42 of 49 (86%) RCC samples, but in only two of 22 (9%) normal kidney and none of five oncocytoma samples. Levels of MN/CA9 expression were significantly higher in tumours consisting only of clear cells than in those containing other cell types (P=0.0189), and MN/CA9 was expressed in 34 of 37 (92%) RCC samples consisting only of clear cells. Tumours of low clinical stage showed a striking increase in MN/CA9 expression, and high MN/CA9 expression was associated with a good patient outcome.

CONCLUSION

These results suggest that MN/CA9 expression is a potential diagnostic biomarker of RCC, especially the clear-cell type, and can be targeted using molecular biological techniques.

Serum vascular endothelial growth factor is a candidate biomarker of metastatic tumor response to ex vivo gene therapy of renal cell cancer

We report the close correlation between changes in serum immunoreactive vascular endothelial growth factor 165 (iVEGF165) levels and metastatic tumor burden measured by computed tomography scan before treatment, during the antitumor response, and during early progression in a patient treated with ex vivo gene therapy for renal cell carcinoma. With the researcher blinded to outcome, iVEGF levels were measured in archived serum samples from a patient with metastatic renal cell carcinoma who demonstrated a 7-month partial remission to treatment with autologous, irradiated human GM-CSF gene transduced tumor vaccine. Although a spontaneous regression could not be formally excluded in this patient, the appearance of 20 new pulmonary metastases on computed tomography scan after nephrectomy and before vaccination indicates that if spontaneous regression occurred, it took place at the start of vaccine treatment.

Clinical significance of serum ferritin in patients with renal cell carcinoma

OBJECTIVES

We examined the serum ferritin levels in 158 patients with renal cell carcinoma and 101 healthy control subjects between 1987 and 1994 to investigate the value of this intracellular protein as a tumor marker.

METHODS

Preoperative and postoperative serum ferritin values were analyzed and the patients were stratified to three groups accordingly: group 1, patients with normal values (N-N); group 2, those with preoperative high and postoperative normal (H-N); and group 3, those with preoperative normal or high with postoperative high ferritin levels (H-H).

RESULTS

The mean serum ferritin level in 101 healthy control subjects was 85.7 +/- 63.6 ng/mL (range, 3.7 to 265.2). The upper limit of normal, which was calculated by adding 2 standard deviations to the mean was 219.9 ng/mL. Mean serum ferritin in patients with renal cell carcinoma was 274.2 +/- 276.3 ng/mL, which was significantly higher than that of control values (P < 0.01). The sensitivity, specificity, and overall accuracy rate for ferritin increase was 94%, 50%, and 61%, respectively. Multivariate analysis showed that the aforementioned grouping and stage of the disease were the two independent prognostic parameters. Preoperative ferritin levels lost its significance on multivariate analysis.

CONCLUSIONS

Our study shows that although serum ferritin was a useful tool in diagnosing and staging patients, it was not ideal in early stages. However serum ferritin seems to be more valuable for follow-up; postoperative values, indeed, predict the prognosis.