Fibronectin concentration in cerebrospinal fluid reflects early central nervous system involvement in children with acute lymphoblastic leukemia

Plasmatic Fibronectin in Malignancies

Plasmatic fibronectin has been studied in tumor patients on the basis of the role that unspecific opsonin may play in tumor growth and spreading. Alterations in fibronectin levels might be used as a biological marker and our purpose has been to evaluate the significance of this test in the biological diagnosis of cancer. When comparing the levels found in the control group (22.86 ± 1.40 mg/dl) and in tumor patients (23.80 ± 1.90 mg/dl), we observed no difference in the overall group. However, in relation to the localization of tumors, a significant increase was found in breast cancer (31.83 ± 3.83 mg/dl) and a significant decrease in squamous cell carcinoma of the head and neck (9.56 ± 1.68 mg/dl). These results suggest that plasmatic fibronectin could be useful as a biomarker in some types of tumors. Our conclusion was confirmed by analysis of ROC curves related to every one of the studied tumors.

Cerebrospinal fluid biomarkers of malignancies located in the central nervous system

CNS malignancies include primary tumors that originate within the CNS as well as secondary tumors that develop as a result of metastatic cancer. The delicate nature of the nervous systems makes tumors located in the CNS notoriously difficult to reach, which poses several problems during diagnosis and treatment. CSF can be acquired relatively easy through lumbar puncture and offers an important compartment for analysis of cells and molecules that carry information about the malignant process. Such techniques have opened up a new field of research focused on the identification of specific biomarkers for several types of CNS malignancies, which may help in diagnosis and monitoring of tumor progression or treatment response. Biomarkers are sought in DNA, (micro)RNA, proteins, exosomes and circulating tumor cells in the CSF. Techniques are rapidly progressing to assess these markers with increasing sensitivity and specificity, and correlations with clinical parameters are being investigated. It is expected that these efforts will, in the near future, yield clinically relevant markers that aid in diagnosis, monitoring and (tailored) treatment of patients bearing CNS tumors. This chapter provides a summary of the current state of affairs of the field of biomarkers of different types of CNS tumors.

Reduced bacterial adhesion to hydrocephalus shunt catheters mediated by cerebrospinal fluid proteins

BACKGROUND

Prosthetic infections are a major problem, requiring complex and lengthy management. The role of blood proteins in the pathogenesis of implant infection has been investigated, but research into the role of CSF protein in shunt infections has not been undertaken, even though a high CSF protein has been assumed to increase the risk of such infections.

METHODS

New shunt catheters were exposed to either CSF or individual protein solutions, and the numbers of radiolabelled staphylococci that adhered to them were compared with controls that had been exposed to saline only.

RESULTS

A significant reduction in bacteria adhering to the test catheter was found in each instance. Furthermore, the CSF with the highest protein content, from a patient with intraventricular haemorrhage, had the greatest inhibitory effect on bacterial adhesion. The effect of the solutions on the hydrophobicity of the silicone rubber was also investigated. The silicone rubber was more hydrophilic, and bacterial adhesion was less, with solutions containing a higher protein content, and these findings were in keeping with the current theories on the mechanism of bacterial adhesion to polymers.

CONCLUSIONS

A high CSF protein content does not predispose to the development of shunt infections.

Fibronectin and sialic acid levels in human meningiomas and gliomas

In this study, fibronectin and sialic acid levels have been assayed in human meningiomas and gliomas. The mean fibronectin and sialic acid levels for human meningiomas were 22.01 +/- 9.70 micrograms/mg protein and 19.58 +/- 4.89 micrograms/mg protein, respectively, and for human gliomas were 27.30 +/- 13.70 micrograms/mg protein and 25.67 +/- 11.60 micrograms/mg protein, respectively, versus 9.23 +/- 5.40 micrograms/mg protein and 13.50 +/- 4.30 micrograms/mg protein for normal brain tissues. Fibronectin and sialic acid levels were significantly higher in human meningiomas (P < 0.01 and P < 0.05) and gliomas (P < 0.001 and P < 0.01) than control group. Also the mean fibronectin and sialic acid levels were found to be 18.27 +/- 7.08 micrograms/mg protein and 17.04 +/- 6.25 micrograms/mg protein in Grade I-II and 32.60 +/- 15.00 micrograms/mg protein and 29.50 +/- 11.60 micrograms/mg protein in Grade III-IV gliomas, respectively. Fibronectin and sialic acid levels were significantly higher in Grade III-IV gliomas than Grade I-II gliomas (P < 0.05).

An improved method for quantification of extra domain A-containing cellular fibronectin (EDAcFN) in different body fluids

A quantitative direct enzyme immunoassay for the extra domain A-containing isoform of cellular fibronectin (EDAcFN) was established for screening of large series of blood samples and various body fluids of different pH and viscosity. The method is based on the monoclonal antibody DH1 recognizing the extra domain A in cellular fibronectin (EDAcFN). Studies on the effect of dilution of plasma and serum samples in this direct assay indicated that the measured concentration of cFN in the samples greatly depend on the ratio of sample dilution. The linearity of the assay was improved with sample dilution and the optimal dilution was 1:5. Stored diluted samples retained their cFN content at +4 degrees C, and -20 degrees C and -70 degrees C for months in contrast to samples stored undiluted. With this direct EIA the detection limit was 0.05 micrograms/ml and the linear portion of the standard curve could be extended above 30 micrograms/ml. Thus, the cFN concentration of blood samples could be measured reliably without inhibition also in samples with very high concentration of cFN. This is particularly important when measuring blood samples from cancer patients, since these samples may contain more than 20 micrograms/ml EDAcFN. The assay was standardized for blood samples but, due to the possibility of sample dilution, it also enabled reliable quantification of EDAcFN in various other body fluids. Undiluted some of the samples with non-neutral pH (urine, bile) or with high viscosity (seminal plasma) interfered with the assay. In addition to blood samples, the EDAcFN concentration was determined in samples of urine, bile, amniotic fluid, cervicovaginal secretions, seminal fluid, cerebrospinal fluid, bronchoalveolar lavage fluid, pleural fluid and saliva. Thereby, this modified method was shown to be applicable to various body fluids.

Aminoterminal propeptide of type III procollagen in cerebrospinal fluid. Variation with age and in childhood leukemia

Analyses of the aminoterminal propeptide of type III procollagen (PIIINP) in the cerebrospinal fluid (CSF) of 55 children and five young adults without any structural central nervous system (CNS) lesion are reported. The concentration was age-dependent, in that infants and small children had quite high values, whereas the concentration remained relatively constant after the age of 1.5 years. The concentrations of PIIINP in the CSF of 44 children with acute lymphoblastic leukemia (ALL) were prospectively determined at the time of diagnosis and during treatment, since deposition of type III collagen is known to occur during fibroproliferative responses triggered by inflammation. Chemical arachnoiditis is known to be associated with intrathecal methotrexate therapy in children with leukemia. The mean concentration in these children at diagnosis (5.8 micrograms/l +/- SD 2.8 micrograms/l) did not differ from that in age-matched controls (6.7 micrograms/l +/- SD 3.2 micrograms/l). Depending on type of the disease, the children were treated according to two different protocols. PIIINP concentrations were significantly higher during the therapy phases which included intrathecally administered methotrexate (P less than 0.001) than at diagnosis of the disease. Corticosteroid treatments were always associated with a significant decrease in PIIINP concentrations (P less than 0.01 and P less than 0.001 in the two groups, respectively), irrespective of the therapy phase. The results suggest that an increase in PIIINP concentration in the CSF of children with ALL is an indicator of a fibroproliferative response in the arachnoid. Corticosteroids may repress this response and possibly also prevent the development of adhesions in the arachnoid.