The Determination of Urinary Oxypurines as Markers of Gastrointestinal Tumors

Plasma levels and urinary excretion of oxypurines – hypoxanthine and xanthine – were evaluated by reverse-phase high-pressure liquid chromatography in 13 patients affected by gastric tumors and in 19 colorectal tumor-bearing patients. Preliminary results indicate higher values of urinary xanthine and an increase in the xanthine/hypoxanthine ratio in cancer patients. The increase was not generalized to all subjects, and did not appear related either to the stage of the disease or to CEA values. The limits within which the determination of urinary oxypurines can be employed as a tumor marker are discussed.

Plasma soluble VEGFR-1 is a potential dual biomarker of response and toxicity for bevacizumab with chemoradiation in locally advanced rectal cancer

We explored plasma and urinary concentrations of two members of the vascular endothelial growth factor (VEGF) family and their receptors as potential response and toxicity biomarkers of bevacizumab with neoadjuvant chemoradiation in patients with localized rectal cancer. The concentrations of VEGF, placental growth factor (PlGF), soluble VEGF receptor 1 (sVEGFR-1), and sVEGFR-2 were measured in plasma and urine at baseline and during treatment. Pretreatment values and changes over time were analyzed as potential biomarkers of pathological response to treatment as well as for acute toxicity in patients with locally advanced rectal cancer treated prospectively in 2002-2008 with neoadjuvant bevacizumab, 5-fluorouracil, radiation therapy, and surgery in a phase I/II trial. Of all biomarkers, pretreatment plasma sVEGFR-1-an endogenous blocker of VEGF and PlGF, and a factor linked with "vascular normalization"-was associated with both primary tumor regression and the development of adverse events after neoadjuvant bevacizumab and chemoradiation. Based on the findings in this exploratory study, we propose that plasma sVEGFR-1 should be further studied as a potential biomarker to stratify patients in future studies of bevacizumab and/or cytotoxics in the neoadjuvant setting.

Identification of urinary modified nucleosides and ribosylated metabolites in humans via combined ESI-FTICR MS and ESI-IT MS analysis

The physiological response of the human body to several diseases can be reflected by the metabolite pattern in biological fluids. Cancer, like other diseases accompanied by metabolic disorders, causes characteristic effects on cell turnover rate, activity of modifying enzymes, and RNA/DNA modifications. This results in an altered excretion of modified nucleosides and biochemically related compounds. In the course of our metabolic profiling project, we screened 24-h urine of patients suffering from lung, rectal, or head and neck cancer for previously unknown ribosylated metabolites. Therefore, we developed a sample preparation procedure based on boronate affinity chromatography followed by additional prepurification with preparative TLC. The isolated metabolites were analyzed by ion trap mass spectrometry (IT MS) and Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS). IT MS was applied for LC-auto MS(3) screening runs and MS(n(n=4-6)) syringe pump infusion experiments, yielding characteristic fragmentation patterns. FTICR MS measurements enabled the calculation of corresponding molecular formulae based on accurate mass determination (mass accuracy: 1-5 ppm for external and sub-ppm values for internal calibration). We were able to identify 22 metabolites deriving from cellular RNA metabolism and related metabolic pathways like histidine metabolism, purine biosynthesis, methionine/polyamine cycle, and nicotinate/nicotinamide metabolism. The compounds 1-ribosyl-3-hydroxypyridinium, 1-ribosyl-pyridinium, and 3-ribosyl-1-methyl-l-histidinium as well as a series of ribosylated histamines, conjugated to carboxylic acids at the N(omega)-position were found as novel urinary constituents. The occurrence of the modified nucleosides 2-methylthio-N(6)-(cis-hydroxyisopentenyl)-adenosine, 5-methoxycarbonylmethyl-2-thiouridine, N(6)-methyl-N(6)-threonylcarbamoyladenosine, and 2-methylthio-N(6)-threonylcarbamoyladenosine in human urine is verified for the first time.

Clinical significance of serum and urinary c-erbB-2 levels in colorectal cancer

In this study we measured serum and urinary c-erbB-2 levels in 63 patients with colorectal cancer and 29 healthy controls, assessing their role in cancer-specific survival and the effects of resectional surgery. Serum and urinary c-erbB-2 levels were measured by an enzyme-linked immunosorbent assay, preoperatively and 7 days following tumor resection. Preoperative serum c-erbB-2 concentrations were significantly higher in the cancer patients and correlated with disease stage and the presence of liver metastases. Urinary c-erbB-2 was detected more often in cancer patients, although levels did not differ from controls and there was no association with any clinicopathological variable. Serum c-erbB-2 levels decreased significantly in those patients resected for cure and were an independent prognostic factor for cancer-specific survival with higher preoperative concentrations correlating with worse overall survival. These findings suggest that serum assessment of c-erbB-2 concentration may be valuable in defining colorectal cancer prognosis.

Assessment of small intestinal damage in patients treated with pelvic radiotherapy

Pelvic radiotherapy almost always induces intestinal symptoms. We investigated the radiation-induced damage to the small intestinal mucosa and evaluated its relationship with symptoms, using cellobiose/mannitol permeability test (CE/MA) and plasma postheparin diamine oxidase test (PHD) in 20 patients treated with pelvic radiotherapy. The symptoms developed during radiotherapy were noted. Intestinal permeability significantly (p=0.013) increased from 0.021 +/- 0.026 to 0.047 +/- 0.055 (mean +/- SD) after 15 days of radiotherapy, while it returned to normal values (0.010 0.015) at the end of radiotherapy. PHD values did not change. All patients developed intestinal symptoms. These findings indicate that pelvic radiotherapy induces an early small bowel mucosa damage followed by mucosal adaptation. Acute intestinal symptoms during pelvic radiotherapy may not depend only on small intestinal mucosal damage.

Chromatographic analysis of the enantiomers of ifosfamide and some of its metabolites in plasma and urine

The enantiomers of the cytostatic drug ifosfamide and the two metabolites 2- and 3-dechloroethylifosfamide were isolated from plasma and urine by liquid-liquid extraction with ethyl acetate, resolved on a Chirasil-L-val gas chromatographic column and detected by a nitrogen-phosphorus-selective flame ionisation detector. Resolution of the racemic compounds for identification purposes was also accomplished with high-performance liquid chromatography on a chiral column. The validated gas chromatographic method was suitable to determine the total concentrations and the enantiomeric composition of ifosfamide and its dechloroethylated metabolites in plasma and urine samples from treated patients. Some metabolic preferences in the metabolism of ifosfamide were found.

Urinary excretion of modified nucleosides as biological marker of RNA turnover in patients with cancer and AIDS

Using boronate gel affinity chromatography and reversed-phase high-performance liquid chromatography (RP-HPLC), a method for the simultaneous determination of 12 urinary modified nucleosides has been developed. The RP-HPLC fractions were identified by gas chromatography/mass spectrometry analysis. The HPLC quantitation of urinary nucleoside levels before and after surgery of cancer patients suggested that urinary 5'-deoxy-5'-methylthioadenosine and N-[(9-beta-D-ribofuranosyl-9H-purine-6-yl) carbamoyl]-L-threonine (t6A) levels were helpful in monitoring therapeutic effects in cancer patients. From the fact that molar ratios of urinary N2,N2-dimethylguanosine (m2 2G)pseudouridine (psi) and t6A/psi in cancer patients were lower than those of normal or post-surgical cancer patients, the increase of rRNA content in cancer tissues growing rapidly was estimated using the stoichiometric relationship between the ratio of the number of residues of their modified nucleoside in RNAs and the proportion of rRNA to total RNAs in average tissues of whole body. Furthermore, from the estimation of RNA turnover using urinary nucleoside levels, it was found that the half-lives of rRNA rather than tRNA of patients with cancer and those of both RNAs in the case of acquired immunodeficiency syndrome (AIDS) were extremely short compared with those of the normal. Thus, we discovered that the selected urinary modified nucleosides were very useful as a biological marker of whole-body RNA turnover in patients with cancer and AIDS.

Urinary epidermal growth factor (hEGF) levels in patients with carcinomas of the breast, colon and rectum

A specific two-site ELISA for human epidermal growth factor (hEGF) has been used to measure urinary hEGF/creatinine ratios in 30 normal subjects, 30 hospital in-patients with breast cancer and 30 hospital in-patients with colonic or rectal cancer. There was no significant difference between patients with breast cancer and controls. Although a statistically significant difference between patients with colorectal cancer and controls was observed, the biological significance of this observation is doubtful. No clear effect of the presence of breast or colorectal carcinoma on the urinary excretion of hEGF has been observed.

Polyamines in colorectal cancer. Evaluation of polyamine concentrations in the colon tissue, serum, and urine of 50 patients with colorectal cancer

Total, free, and acetylated polyamine concentrations were measured simultaneously in colon tissue, serum, and urine of 50 patients with histologically proven colorectal cancer, 40 patients with nonmalignant gastrointestinal diseases, and 30 healthy volunteers. Compared with histologically unaffected colon tissue, concentrations were significantly (P less than 0.001) higher for putrescine, elevated for cadaverine, and nearly identical for spermidine and spermine in colon carcinoma, whereas N1-acetylated and N8-acetylated spermidine were detectable in cancer tissue only. Serum and urine concentrations of all polyamines except total cadaverine and spermine in serum and free spermine in urine were significantly elevated compared with healthy controls and highest sensitivity for colon cancer was found for total spermidine (89.15%) in serum and acetylputrescine (84.5%), total putrescine (84.0%), N1-acetylspermidine (79.3%), and total spermidine (92.1%) in urine. However, nonmalignant gastrointestinal diseases partly showed similar elevations which resulted in a low specificity for polyamines in colorectal cancer. Therefore, polyamines are of little value only as diagnostic markers in colorectal carcinoma. Since polyamine concentrations in serum and urine normalized in patients after curative operation while they were further elevated in patients with proven tumor relapse or metastases, these substances might play a clinical role in predicting therapeutic success or indicating relapse of the tumor. Although a significant dependency of polyamine concentrations in serum or urine to Dukes' classification, tumor localization, CEA, CA 19-9, or CA 125 did not exist, a significant linear correlation was found for tumor size.

Urinary polyamines in colorectal cancer

Urine polyamine content is increased in patients with colorectal malignancy and may be a useful tumor marker in the management of these patients. Urinary excretion of putrescine and spermidine was measured preoperatively and in the first week postoperatively in nine patients with inflammatory bowel disease, eight with other benign colorectal disease, and 13 with colorectal cancer. Preoperative urine putrescine levels were elevated similarly in patients with inflammatory bowel disease and malignancy. Polyamine levels were increased in all three groups in the early postoperative period. Urinary polyamine excretion did not correlate with serum CEA levels, tumor volume, or stage of disease in patients with cancer. Because elevated levels of urinary polyamines are not specific for malignancy and do not correlate with other prognostic indicators, such measurements are unlikely to be useful in tumor detection and determining prognosis. Polyamine levels, however, may prove useful in monitoring response to therapy and detecting recurrences in individual patients.

Tumor markers in colorectal carcinoma. An evaluation of carcinoembryonic antigen, tissue polypeptide antigen, placental alkaline phosphatase and pseudouridine

The biologic markers carcinoembryonic antigen (CEA), tissue polypeptide antigen (TPA), placental alkaline phosphatase ( PLAP ) and pseudouridine were analysed in 37 patients with colorectal carcinoma. CEA, TPA and PLAP were derived from the serum and pseudouridine from the urine. The incidence of all four markers increased with advancing stages of the disease. Patients with distant metastases had elevated levels of CEA, TPA, PLAP and pseudouridine in 85, 27, 18 and 33 per cent of the total cases, respectively. When survival was compared, patients with 2 to 4 elevated markers had shorter survival than those with none or only one elevated marker.

Treatment of the carcinoid tumor and the malignant carcinoid syndrome

Certainly in treatment of the carcinoid tumor surgery has a well-established curative and palliative potential. The primary challenge is a knowledgable marriage between stage of disease and aggressiveness of operative procedure. Nonsurgical treatment of the malignant disease per se has thus far not produced optimum results and, in the opinion of this author, should still be confined to a clinical research setting. It would seem very doubtful, however, that the more mundane types of trials, empirically testing drug after drug and arbitrarily concocted drug combinations, is the most productive road to follow. There is an evident need for more sophisticated approaches to this tumor, which has unique metabolic characteristics that should be pharmacologically exploitable. Past experience has indicated that such a setting may permit dramatic therapeutic accomplishment. There is a strong need for animal models or established cell lines which would facilitate preclinical therapeutic exploration. The carcinoid syndrome presents an unparalleled opportunity for fundamental physiologic observations and for experimental therapeutic study that can have applicability not only in palliating the syndrome itself but also in the management of other pathophysiologic states that may involve more subtle abnormalities of the same hormonal mechanisms. The patient with the carcinoid tumor should not just be a fascinating curio for grand rounds exhibition. He should be a focal point for research involving an experienced, multidisciplinary clinical team supported by devoted basic scientists. If our patient resources and efforts can be concentrated in this manner, the carcinoid should be a strong candidate for the next medically curable human cancer.

Polyamines in colorectal cancer--a clinical and experimental approach

The urinary polyamines putrescine, spermidine and spermine were measured prior to operation in 10 patients with colorectal cancer and 10 control subjects. Carcinoembryonic antigen assays were also performed in an attempt to correlate these values with polyamine excretion. The total polyamine rates in patients with colorectal cancer were 3.2 +/- 1.5 (SD) mg/24 h and 2.6 +/- 1.2 (SD) mg/24 h in the controls. The difference between the group with colorectal cancer and the controls was not statistically significant. Urinary polyamines were also measured in an experimental animal model for colorectal cancer in which tumour cell mass could be assessed. Only marginal differences occurred in polyamine rates between animals with extensive tumours and controls. These findings suggest that urinary polyamine measurement is unlikely to be a useful procedure to assess tumour cell mass in patients with colorectal cancer.

Urinary pseudouridine/creatinine ratio as an indicator of gastrointestinal cancer

Urinary pseudouridine/creatinine ratio was determined in 74 patients with gastrointestinal tumours and 34 patients with no known malignant disease. The reproducibility of a single random urine sample was demonstrated. The mean ratio for control patients was 26.9 +/- 7.7 nmol/mumol and no control patient exceeded the mean by 2 standard deviations. There was no difference in the ratio between the sexes. Sixty-five per cent of colon cancer patients and 37.5 per cent of gastric and rectal cancer patients exceeded this upper limit of normality. There was no correlation between pseudouridine/creatinine ratio and histological differentiation, liver involvement or stage in either colorectal or gastric cancer patients. Urinary pseudouridine/creatinine ratio is one of the better non-specific cancer markers and may be particularly useful for detecting colonic cancer.

Detection of monoclonal antibody-defined colorectal carcinoma antigen by solid-phase binding inhibition radioimmunoassay

We have established a solid-phase binding inhibition radioimmunoassay for the detection of colorectal carcinoma-specific antigens in tissue culture supernatants of human colorectal carcinoma cell lines and in serum and urine of colorectal carcinoma patients. Using the [3H]glucosamine-labeled cell membrane glycolipid antigen and colorectal carcinoma-specific monoclonal antibodies in this assay, we have been able to detect several human colorectal carcinoma membrane-specific antigens that are released from the cell membrane into tissue culture supernatants, and an antigen detected by antibodies 1116-NS-19-9 and 1116-NS-52a that is found only in the serum and urine of cancer patients.

The role of stress factors in the postoperative course of patients with rectal cancer

The authors studied 82 patients with rectal cancer who underwent radical surgical treatment at the N.N. Petrov Oncological Research Institute of the Ministry of Health of the USSR in 1974-1975. They defined the markedness of patients' psychogenic disturbances in the pre- and postoperative period and measured the level of catecholamines in urine and that of 11-oxycorticosteroids in blood. The findings showed the highest frequency of postoperative complications (68%) in the group of patients who evidenced severe psychic reactions when they were admitted to the clinic. These data correlated with a higher level of catecholamines in the urine and of 11-oxycorticosteroids in the blood before surgery, and with a marked decrease of catecholamine excretion on the sixth day after the operation. This may indicate sympathetic-adrenal system exhaustion and play a certain part in the development of postoperative complications.

Isolation and partial characterization of macromolecular urinary aggregates containing carcinoembryonic antigen-like activity

Carcinoembryonic antigen-like substances in the urine of patients with bladder carcinoma and of healthy male subjects occur in a wide range of average molecular sizes. Some of these substances are glycoproteins giving reactions of antigenic identity with carcinoembryonic antigen (CEA) derived from colorectal carcinoma and occur in aggregation with proteins showing antigen specificities of albumin, haptoglobin and the heavy chains of immunoglobulins G, A and M. Recoveries of CEA-like activities, following Sepharose 4B chromatography of urinary materials of molecular size > 3 × 10(4), varied from 40 to 1530%. Treatment with 1 mol/1 HClO(4) caused an apparent solubilization of 85% of the CEA-like activity of such materials from the urine of a patient with bladder carcinoma and raised the specific CEA-like activity of the solubilized product to 379% of that of the untreated materials.