Evaluation of Glucose 6-Phosphate Dehydrogenase, Pyruvate Kinase, and New Generation Inflammation Biomarkers in Prolonged Neonatal Jaundice

Background and Objectives: To evaluate the clinical findings of glucose 6-phosphate dehydrogenase (G6PD) and pyruvate kinase (PK) deficiency in prolonged jaundice and to determine whether the systemic immune inflammation index (SII), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) can be used in the diagnosis of neonatal prolonged jaundice. Materials and Methods: Among full-term neonates with hyperbilirubinemia who were admitted to Medicine Hospital between January 2019 and January 2024 with the complaint of jaundice, 167 infants with a serum bilirubin level above 10 mg/dL, whose jaundice persisted after the 10th day, were included in this study. Results: G6PD activity was negatively correlated with NLR, SII, age, and hematocrit (Hct). There was a weak negative correlation between G6PD and NLR and a moderate negative correlation between G6PD activity and SII when adjusted for age and Hct. PK activity showed no significant correlation with G6PD, NLR, PLR, SII, age, and Hct. A linear relationship was observed between G6PD activity and SII and NLR. Conclusions: NLR and SII can be easily calculated in the evaluation of prolonged jaundice in G6PD deficiency has a considerable advantage. NLR and SII levels may contribute by preventing further tests for prolonged jaundice and regulating its treatment. It may be useful to form an opinion in emergencies and in early diagnostic period.

Evaluation of a Commercial TIMS-Q-TOF Platform for Native Mass Spectrometry

Mass-spectrometry based assays in structural biology studies measure either intact or digested proteins. Typically, different mass spectrometers are dedicated for such measurements: those optimized for rapid analysis of peptides or those designed for high molecular weight analysis. A commercial trapped ion mobility-quadrupole-time-of-flight (TIMS-Q-TOF) platform is widely utilized for proteomics and metabolomics, with ion mobility providing a separation dimension in addition to liquid chromatography. The ability to perform high-quality native mass spectrometry of protein complexes, however, remains largely uninvestigated. Here, we evaluate a commercial TIMS-Q-TOF platform for analyzing noncovalent protein complexes by utilizing the instrument's full range of ion mobility, MS, and MS/MS (both in-source activation and collision cell CID) capabilities. The TIMS analyzer is able to be tuned gently to yield collision cross sections of native-like complexes comparable to those previously reported on various instrument platforms. In-source activation and collision cell CID were robust for both small and large complexes. TIMS-CID was performed on protein complexes streptavidin (53 kDa), avidin (68 kDa), and cholera toxin B (CTB, 58 kDa). Complexes pyruvate kinase (237 kDa) and GroEL (801 kDa) were beyond the trapping capabilities of the commercial TIMS analyzer, but TOF mass spectra could be acquired. The presented results indicate that the commercial TIMS-Q-TOF platform can be used for both omics and native mass spectrometry applications; however, modifications to the commercial RF drivers for both the TIMS analyzer and quadrupole (currently limited to m/z 3000) are necessary to mobility analyze protein complexes greater than about 60 kDa.

Reduction in abdominal symptoms (CFAbd-Score), faecal M2-pyruvate-kinase and Calprotectin over one year of treatment with Elexacaftor-Tezacaftor-Ivacaftor in people with CF aged ≥12 years - The RECOVER study

BACKGROUND

RECOVER is a multicentre post-approval study of Elexacaftor/Tezacaftor/Ivacaftor (ETI) in pwCF in Ireland and the UK. The CFAbd-Score is the first validated CF-specific patient reported outcome measure (PROM) focusing on gastrointestinal symptoms; it comprises 28 items in 5 domains. In a preliminary study, we previously reported reductions in abdominal symptoms (AS) in pwCF after 26 weeks of ETI-therapy using the CFAbd-Score.

AIM

to assess changes in AS in a second, large cohort and explore novel GI-biomarkers of gut inflammation and cell-proliferation in pwCF over one year of ETI-therapy.

METHODS

Participants were recruited as part of the RECOVER study at 8 sites (Ireland&UK). The CFAbd-Score was administered prior to ETI-initiation, and subsequently at 1,2,6 and 12 months on treatment. Faecal M2-pyruvate kinase (M2-PK) and calprotectin (FC) were quantified in samples collected at baseline, 1 and 6 months.

RESULTS

108 CFAbd-Scores and 73 stool samples were collected at baseline. After 12 months of ETI-therapy, total CFAbd-Scores had significantly declined (15.0±1.4→9.8±1.2pts/p<0.001), and so had all its five domains of "pain" (16.9±2.0pts→9.9±1.8pts/p<0.01), "GERD" (14.4±1.8→9.9±1.6/p<0.05), "disorders of bowel movements" (19.2±1.4→14.1±1.5/p<0.01), "appetite" (7.0±1.1→4.6±1.2/p<0.01) and "impaired-QoL" (13.3±1.9→7.5±1.5/p<0.001). Levels of M2-PK and FC significantly decreased during ETI-therapy.

DISCUSSION

In-depth analysis of AS with the CFAbd-Score reveals a statistically significant, clinically relevant and sustained improvement with ETI. We attribute this to high sensitivity of the implemented CF-specific PROM, developed and validated following FDA-guidelines. Furthermore, for the first time during ETI-therapy a significant decline in faecal M2-PK, a marker of inflammation and cell-proliferation, was found, in parallel to FC.

Pyruvate Kinase M (PKM) binds ribosomes in a poly-ADP ribosylation dependent manner to induce translational stalling

In light of the numerous studies identifying post-transcriptional regulators on the surface of the endoplasmic reticulum (ER), we asked whether there are factors that regulate compartment specific mRNA translation in human cells. Using a proteomic survey of spatially regulated polysome interacting proteins, we identified the glycolytic enzyme Pyruvate Kinase M (PKM) as a cytosolic (i.e. ER-excluded) polysome interactor and investigated how it influences mRNA translation. We discovered that the PKM-polysome interaction is directly regulated by ADP levels-providing a link between carbohydrate metabolism and mRNA translation. By performing enhanced crosslinking immunoprecipitation-sequencing (eCLIP-seq), we found that PKM crosslinks to mRNA sequences that are immediately downstream of regions that encode lysine- and glutamate-enriched tracts. Using ribosome footprint protection sequencing, we found that PKM binding to ribosomes causes translational stalling near lysine and glutamate encoding sequences. Lastly, we observed that PKM recruitment to polysomes is dependent on poly-ADP ribosylation activity (PARylation)-and may depend on co-translational PARylation of lysine and glutamate residues of nascent polypeptide chains. Overall, our study uncovers a novel role for PKM in post-transcriptional gene regulation, linking cellular metabolism and mRNA translation.

Faecal biomarkers do not always identify pre-cancerous lesions in patients who present in primary care with bowel symptoms

AIM

To determine if tumour-derived M2-PK is potentially a more accurate biomarker of pre-cancerous bowel lesions in patients who present in primary care with bowel symptoms than the detection of faecal haemoglobin.

METHODS

Patients requested by their general practitioners (GPs) to provide a stool sample to determine the presence of faecal haemoglobin consented for the same stool samples to be tested for the presence of M2-PK. For comparison M2-PK levels were also measured in stool samples from patients recently identified with colorectal cancer and healthy controls who self-reported no bowel problems at the time of sampling.

RESULTS

M2-PK levels measured in 185 GP-derived samples were comparable to the control cohort (57 healthy controls) and notably lower than those in the 57 patients with CRC (2.6, 3.2 and 18.2U/ml-1, respectively). Sixty-seven of the GP patients were referred for colonoscopy. While 26 of these patients had a positive M2-PK, only 10 were found to have colonic lesions. Conversely, 18 of the 41 patients who had a negative M2-PK were found to have lesions that included one CRC, 13 adenomas and four other polyps. The FIT also failed to identify colonic disease in 19 of 48 patients referred for colonoscopy. There was, however, a significant association between lesions greater than 1cm and a positive FIT (p<0.02) that was not the case with M2-PK. A positive FIT identified one patient in the GP patient cohort subsequently diagnosed with colorectal cancer at follow-up colonoscopy whereas the same stool sample tested negative for M2-PK.

CONCLUSIONS

Measurement of faecal M2-PK levels lacks the specificity and sensitivity (and therefore diagnostic accuracy) to identify the individuals who should be progressed for clinical follow-up. Accordingly, M2-PK is not is not a robust biomarker for identifying pre-cancerous bowel lesions in a primary care setting.

The Multifarious Functions of Pyruvate Kinase M2 in Oral Cancer Cells

Head and neck cancers, including oral squamous cell carcinoma (OSCC), are the sixth most common malignancies worldwide. OSCC frequently leads to oral dysfunction, which worsens a patient’s quality of life. Moreover, its prognosis remains poor. Unlike normal cells, tumor cells preferentially metabolize glucose by aerobic glycolysis. Pyruvate kinase (PK) catalyzes the final step in glycolysis, and the transition from PKM1 to PKM2 is observed in many cancer cells. However, little is known about PKM expression and function in OSCC. In this study, we investigated the expression of PKM in OSCC specimens and performed a functional analysis of human OSCC cells. We found that the PKM2/PKM1 ratio was higher in OSCC cells than in adjacent normal mucosal cells and in samples obtained from dysplasia patients. Furthermore, PKM2 expression was strongly correlated with OSCC tumor progression on immunohistochemistry. PKM2 expression was higher during cell growth, invasion, and apoptosis in HSC3 cells, which show a high energy flow and whose metabolism depends on aerobic glycolysis and oxidative phosphorylation. PKM2 expression was also associated with the production of reactive oxygen species (ROS) and integration of glutamine into lactate. Our results suggested that PKM2 has a variety of tumor progressive functions in OSCC cells.

Power of screening tests for colorectal cancer enhanced by high levels of M2-PK in addition to FOBT

Colorectal cancer (CRC) is a multistep process that involves adenoma-carcinoma sequence. CRC can be prevented by routine screening, which can detect precancerous lesions. The aim of this study is to clarify whether faecal occult blood test (i-FOBT), tumor M2 pyruvate kinase (t-M2-PK), and endocannabinoid system molecules (cannabinoid receptors type 1-CB1, type 2-CB2, and fatty acid amide hydrolase-FAAH) might represent better diagnostic tools, alone or in combination, for an early diagnosis of CRC. An immunochemical FOB test (i-FOBT) and quantitative ELISA stool test for t-M2-PK were performed in 127 consecutive patients during a 12 month period. Endocannabinoid system molecules and t-M2-PK expression were detected by immunostaining in healthy tissues and normal mucosa surrounding adenomatous and cancerous colon lesions. i-FOBT and t-M2-PK combination leads to a better diagnostic accuracy for pre-neoplastic and neoplastic colon lesions. T-M2-PK quantification in stool samples and in biopsy samples (immunostaining) correlates with tumourigenesis stages. CB1 and CB2 are well expressed in healthy tissues, and their expression decreases in the presence of advanced stages of carcinogenesis and disappears in CRC. FAAH signal is well expressed in normal mucosa and low-risk adenoma, and increased in high-risk adenoma and carcinoma adjacent tissues. This study shows that high levels of t-M2-PK in addition to FOBT enhance the power of a CRC screening test. Endocannabinoid system molecule expression correlates with colon carcinogenesis stages. Developing future faecal tests for their quantification must be undertaken to obtain a more accurate early non-invasive diagnosis for CRC.

Correlation between Faecal Tumour M2 Pyruvate Kinase and Colonoscopy for the Detection of Adenomatous Neoplasia in a Secondary Care Cohort

BACKGROUND AND AIMS

Colorectal cancer screening programmes that target detection and excision of adenomatous colonic polyps have been shown to reduce colorectal cancer related mortality. Many screening programmes include an initial faecal occult blood test (FOBt) prior to colonoscopy. To refine the selection of patients for colonoscopy other faecal-based diagnostic tools have been proposed, including tumour M2-pyruvate kinase (tM2-PK). To determine whether tM2-PK quantification may have a role in diverse settings we have assessed the assay in a cohort of patients derived from both the England bowel cancer screening programme (BCSP) and symptomatic individuals presenting to secondary care.

METHOD

Patients undergoing colonoscopy provided faecal samples prior to bowel preparation. Faecal tM2-PK concentrations were measured by ELISA. Sensitivity, specificity, positive predictive value, negative predictive value and ROC analyses were calculated.

RESULTS

Ninety-six patients returned faecal samples: 50 of these with adenomas and 7 with cancer. Median age was 68. Median faecal tM2-PK concentration was 3.8 U/mL for individuals without neoplastic findings at colonoscopy, 7.7 U/mL in those with adenomas and 24.4 U/mL in subjects with colorectal cancer (both, p=0.01). ROC analysis demonstrated an AUROC of 0.66 (sensitivity 72.4%, specificity 48.7%, positive predictive value 67.7%, negative predictive value 36.7%). Amongst BCSP patients with a prior positive FOBt faecal tM2-PK was more abundant (median 6.4 U/mL, p=0.03) and its diagnostic accuracy was greater (AUROC 0.82).

CONCLUSION

Our findings confirm that faecal tM2-PK ELISA may have utility as an adjunct to FOBt in a screening context, but do not support its use in symptomatic patients.

[Indicators of inflammatory process in stool in diagnostics and monitoring of inflammatory bowel diseases]

In the recent decades the rapid development of the studies on new methods used in diagnosis, differential diagnosis, and monitoring the treatment of inflammatory bowel diseases has been observed. To the diagnostics of gastrointestinal disorders new methods such as endoscopic capsule and imaging methods including magnetic resonance have been introduced. Markers of inflammation detected in stool play significant role in the diagnostics. To the best known belong calprotectine and lactoferrin, which are produced by neutral granulocytes. In the present review we have presented the clinical usefulness of detection in the stool of calprotectin, lectoferrin, S100A12 protein and pyruvate kinase. Clinical usefulness of these markers were used in diagnosis, assessment of the treatment results, disease relapse and mucosal healing in inflammatory bowel disease. Determination of fecal calprotectin and lactoferrin in the process of mucosal healing in ulcerative colitis or Crohn's disease are of particular value. Confirmation of these results in multicenter prospective trials will enable in the future to reduce the number of control colonoscopies, which in children are performer under general anesthesia.

Expression of pyruvate kinase M2 in human colorectal cancer and its prognostic value

Reprogrammed metabolism is a hallmark of cancer cells. Pyruvate kinase isozyme type M2 (PKM2), which is frequently up-regulated in multiple human malignancies, has been demonstrated to play a critical function in glucose metabolism, gene transcription and tumorigenesis. However, limited knowledge is known about the expression pattern and prognostic value of PKM2 in colorectal cancer (CRC). In this study, we first observed that the mRNA level of PKM2 is commonly up-regulated in CRC tissues compared with their normal counterparts as demonstrated by data derived from Oncomine database. Similar results were also found in 32 paired CRC tumor and non-tumor specimens in our cohort and 4 CRC cell lines. Furthermore, by a large scale of immunohistochemical analysis in a tissue microarray containing 345 cases of CRC specimens, we demonstrated that the protein expression of PKM2 expression is up-regulated in 79.4% (274/345) samples detected and elevated PKM2 expression is closely correlated with enhanced TNM stage and higher serum CEA level. Meanwhile, Kaplan-Meier survival analysis showed that CRC patients with a higher PKM2 expression have a poorer clinical outcome than those with a lower PKM2 expression. Multivariate Cox regression analysis revealed that PKM2 and TNM stage are two independent prognostic factors for overall survival rate of CRC patients. Taken together, our studies reveal the prognostic value of PKM2 in CRC and support that PKM2 may act as a molecular target for CRC treatment.

Comparative effectiveness of pyruvate kinase M2 in bile, serum carbohydrate antigen 19-9, and biliary brushings in diagnosing malignant biliary strictures

BACKGROUND

The role of M2-PK (pyruvate kinase) in bile has not been studied in comparison with brushings and carbohydrate antigen (CA) 19-9 in the diagnosis of malignant biliary strictures.

AIM

To compare the diagnostic accuracy of biliary M2-PK with cytology and serum CA 19-9 METHODS: In this prospective cross-sectional study, bile was aspirated in 74 patients (discovery and validation cohort) undergoing endoscopic retrograde cholangiopancreatography. Levels of M2-PK were measured in bile and compared to brushings for cytology and CA 19-9.

RESULTS

In the discovery cohort, the median bile M2-PK levels were significantly elevated in patients with malignant biliary strictures [187.9 U/l (interquartile range (IQR) 3.5, 3626.8)] compared to those with benign biliary conditions and primary sclerosing cholangitis [0 U/l (IQR 0, 15)] (P = 0.007). A M2-PK cutoff value of 109.1 U/l distinguished malignant from benign conditions with a sensitivity and specificity of 52.9 and 94.1 %, respectively, and area under curve (AUC) of 0.77. The sensitivity of CA 19-9 and brushings in diagnosing cancer was 52.9 % and 11.1 % and specificity 94.1 and 100 %, respectively. The presence of elevated M2-PK >109.1 U/l or CA 19-9 >33 U/ml or positive brushing was 88.2 % sensitive and 88.2 % specific, AUC of 0.89 in the diagnosis of malignancy. The diagnostic accuracy was confirmed in the validation cohort.

CONCLUSIONS

As a stand-alone factor, none of the markers were able to distinguish benign from malignant biliary strictures with a high sensitivity. However, a combination was highly sensitive in diagnosing malignant biliary strictures.

Fecal pyruvate kinase is not suitable for discrimination between inflammatory bowel disease exacerbation and acute gastroenteritis

INTRODUCTION

In inflammatory bowel diseases (IBD) diarrhea can be caused by exacerbation and/or infectious agents. Fecal calprotectin (FC) is a well-established biomarker of intestinal inflammation in IBD. However, its usefulness in depiction of IBD exacerbation from infectious diarrhea is limited. The value of fecal pyruvate kinase isoenzyme type 2 (M2-PK) in this application remains unknown.

AIM

To compare the performance of M2-PK and FC in discriminating between diarrhea caused by IBD and infectious agents.

MATERIALS AND METHODS

One hundred three patients were enrolled for the study, including 32 with ulcerative colitis (UC), 21 with Crohn's disease (CD), 29 with acute diarrhea caused by rotavirus (AD-RV), and 21 with acute diarrhea caused by Salmonella enteritidis (AD-SE). M2-PK and FC were measured using ELISA. Areas under receiver operating characteristic curves (AUCs), sensitivities and specificities for both tests in distinguishing between patient subgroups with moderate to severe UC and CD from AD-RV and AD-SE were calculated.

RESULTS

Differences in AUCs between M2-PK and FC for distinguishing UC [CD] from AD-RV were -0.06 (p < 0.028) [-0.10 (p < 0.0018)] and for differentiating UC [CD] from AD-SE were 0.03 (NS) [-0.19(p < 0.0011)].M2-PK sensitivities and specificities in distinguishing UC [CD] from AD-RV were 75.0%[71.4%] and 89.7% [89.7%] and for differentiation of UC [CD] from AD-SE were 56.3% [71.4%] and 95.2[57.1%].

CONCLUSIONS

The performance of M2-PK in distinguishing between children with moderate-to-severe IBD and patients with infectious gastroenteritis was inferior to FC. Neither test had sensitivity ands pecificity sufficient for everyday clinical application.

Comparison of faecal M2-PK and FIT in a population-based bowel cancer screening cohort

BACKGROUND

Screening for colorectal cancer improves outcomes and is cost effective. Stool-based tests have the highest participation rates in screening programmes. Their efficacy is limited by the relatively low sensitivity and specificity compared with colonoscopy. Stool levels of M2-PK, a dimeric form of the enzyme pyruvate kinase, correlate with colorectal cancer and neoplasia. A combination of stool markers may enhance screening performance; however, it remains to be determined whether an additional test would affect participation rates negatively.

AIMS

The aim of this study was to assess the performance of faecal M2-PK and faecal immunochemical test (FIT) and their combined effect in a screening programme.

MATERIALS AND METHODS

Within round 2 of our biennial FIT-based pilot, all invitations additionally included an M2-PK kit. A FIT greater than 100 ngHb/ml and/or an M2-PK greater than 4 U/ml were considered positive. FIT-positive or M2-PK-positive patients were offered a colonoscopy.

RESULTS

In all, 1800 combined M2-PK and FIT invites were sent out, and 879 (49%) samples were analysed. Overall positivity was 27% (n=245). Only 23 (2.6%) patients were positive for both tests. In all, 186 (88%) screening colonoscopies were performed. The adenoma detection rate for M2-PK-positive patients (n=157) was significant at 25% (n=40), and 3% (n=5) had advanced lesions. In FIT-positive patients (n=51), the adenoma detection rate was 29% (n=15), with significantly more, 21% (n=11), having advanced lesions (P<0.001, confidence interval 0.117-0.156). Had FIT only been tested, 70% (n=35) fewer patients would have had polyps removed.

CONCLUSION

The addition of M2-PK in a biennial bowel screening programme is acceptable to patients, feasible and detects additional adenomas, potentially at an earlier stage.

[Utility of fecal markers of inflammation in the diagnostics of inflammatory bowel diseases]

Many reports from recent years indicate the important role of fecal markers of inflammation. These are proteins produced by neutrocytes, monocytes and hepatocytes. The concentration of these proteins increases in the process of inflammation. These parameters are very sensitive because changes in their levels particularly reflect inflammatory conditions in the intestines. In this study we discuss the role of measurements of proteins such as: alpha 1-antitrypsin, myeloperoxydase, lactoferrin, calprotectin, S100A12 protein and pyruvate kinase in stool. The largest number of studies indicating the usefulness in the diagnosis and monitoring the course of inflammatory bowel diseases concerns stool lactoferrin and calprotectin.

Beneficiary effect of Tinospora cordifolia against high-fructose diet induced abnormalities in carbohydrate and lipid metabolism in Wistar rats

High intake of dietary fructose has been shown to exert a number of adverse metabolic eff ects in humans and experimental animals. The present study was designed to investigate the eff ect of the aqueous extract of Tinospora cordifolia stem (TCAE) on the adverse eff ects of fructose loading toward carbohydrate and lipid metabolism in rats. Adult male Wistar rats of body weight around 200 g were divided into four groups, two of which were fed with starch diet and the other two with high fructose (66 %) diet. Plant extract of TC (400 mg/kg/day) was administered orally to each group of the starch fed rats and the highfructose fed rats. At the end of 60 days of experimental period, biochemical parameters related to carbohydrate and lipid metabolism were assayed. Hyperglycemia, hyperinsulinemia, hypertriglyceridemia, insulin resistance, and elevated levels of hepatic total lipids, cholesterol, triglycerides, and free fatty acids (p < 0.05) observed in fructose-fed rats were completely prevented with TCAE treatment. Alterations in the activities of enzymes of glucose metabolism (hexokinase, phosphofructokinase, pyruvate kinase, glucose-6-phosphatase, fructose-1,6-bisphosphatase, and glucose-6-phosphate dehydrogenase) and lipid metabolism (fatty acid synthetase, lipoprotein lipase, and malic enzyme) as observed in the high fructose-fed rats were prevented with TCAE administration. In conclusion, our fi ndings indicate improvement of glucose and lipid metabolism in high-fructose fed rats by treatment with Tinospora cordifolia, and suggest that the plant can be used as an adjuvant for the prevention and/or management of insulin resistance and disorders related to it.

Four-gene expression ratio test for survival in patients undergoing surgery for mesothelioma

BACKGROUND

Malignant pleural mesothelioma has few effective treatments, one being cytoreductive surgery. We previously developed a gene ratio test to predict outcome of malignant pleural mesothelioma patients undergoing surgery. In this study, we investigated the predictive value and technical assay performance of this test in patients with malignant pleural mesothelioma.

METHODS

Clinical data were obtained prospectively from 120 consecutive patients with malignant pleural mesothelioma who were scheduled for debulking surgery at one institution. Specimens were obtained at surgery or by pleural biopsy examination. Expression data for four genes were collected from tumor specimens, and three ratios of gene expression (TM4SF1/PKM2, TM4SF1/ARHGDIA, and COBLL1/ARHGDIA) were determined by quantitative reverse transcriptase-polymerase chain reaction. Patients were assigned to good or poor outcome groups by the gene ratio test. Survival was estimated by the Kaplan-Meier method and the log-rank test in univariate analyses. A multivariable Cox proportional hazards model was used to control for prognostic factors. Technical robustness was determined by using up to 30 specimens per patient, two biopsy techniques, and two performance sites. All statistical tests were two-sided.

RESULTS

The test predicted overall survival (P < .001) and cancer-specific survival (P = .007) in univariate analysis and overall survival in multivariable analysis (hazard ratio for death = 2.09, 95% confidence interval [CI] = 1.27 to 3.45, P = .004). The test was reproducible within patients and repeatable between two determinations for specimens with widely varying tumor cell contents. Repeatability between two determinations was 88.5% (95% CI = 84.0% to 92.2%) or, when technically unacceptable test values were excluded, 91.9% (95% CI = 87.4% to 95.1%). Reproducibility between two determinations was 96.1% (95% CI = 86.5% to 99.5%). Combining the gene ratio test and other prognostic factors allowed prospective discrimination between patients at high risk (median survival = 6.9 months, 95% CI = 2.6 to 8.9 months; 3-year survival = 0%) and low risk (median survival = 31.9 months, 95% CI = 21.9 to 41.7 months; 3-year survival = 42%).

CONCLUSION

The gene ratio test for survival of patients with malignant pleural mesothelioma has robust predictive value and technical assay performance.

[Prevention of colon cancer--update 2008]

Today effective prevention of colorectal cancer can be done. For primary prevention there are good data for the recommendation of regular physical activity and body weight reduction if BMI is greater than 25 kg/m(2). Furthermore colorectal cancer risk correlates with alcohol intake and the harmful role of tobacco is well documented. But the influence of nutrition seems to be small. The results of a lot of studies are inconsistent. Diets high in fiber are recommended. The intake of red or processed meat seems to be associated with a higher risk for colorectal cancer. With the additive intake of vitamins and antioxidants the risk of colorectal cancer cannot be reduced. At present the use of drugs like aspirin, NSAD or statins cannot be recommended for primary prevention. The fecal occult blood test (FOBT) is the standard of the non-invasive screening methods. But regarding sensitivity and specificity there are better results for the new immunochemical fecal occult blood tests. The TuM2-PK test is an another screening method, but seems to be inferior to the immunochemical tests. Colonoscopy is the gold standard in the prevention of colorectal cancer. But it is important to improve the acceptance of this screening method in general population.

Faecal dimeric M2 pyruvate kinase in colorectal cancer and polyps correlates with tumour staging and surgical intervention

OBJECTIVE & METHOD

A dimeric form of pyruvate kinase isoenzyme (tumour M2-PK) is predominantly found in highly proliferating cells. Sandwich ELISA with monoclonal antibodies against dimeric (tumour) M2-PK was used to measure faecal tumour M2-PK in; 13 controls, 10 patients with colonic polyps and 32 patients with colorectal cancer.

RESULTS

Levels of faecal tumour M2-PK were higher in patients with colorectal cancer (median 11.72 U/ml; range 0.9-146.95 U/ml, P = 0.0001) and polyps greater than 10 mm (median 2.54 U/ml; range 0.9-29.46 U/ml, P = 0.041) when compared with controls (median 1.75 U/ml; range 0.9-3.41 U/ml). Furthermore, levels were higher in stages Duke's B (P = 0.013) and Duke's C (P = 0.43) than in Duke's A. Six months postsurgery faecal tumour M2-PK levels fell significantly to 3.46 U/ml (range 1.03-9.05 U/ml, P = 0.001). The sensitivity of a positive faecal tumour M2-PK test, defined as a level above 3.33 U/ml, was 91% for colorectal cancer, 60% for >10 mm and 20% for <10 mm polyps, with a specificity of 92%.

CONCLUSION

Faecal tumour M2-PK is a highly sensitive marker for colorectal cancer and larger polyps. It also correlates with more advanced stages of colorectal cancer and its reduction is associated with successful surgical intervention.

Stool test for colorectal cancer screening--it's time to move!

Fecal occult blood testing (FOBT) is the most widely prescribed screening test for colorectal cancer (CRC) because it is simple, non-invasive, and it has been demonstrated that it reduces the mortality due to colorectal carcinomas (CRC). However, guaiac based fecal blood tests (gFOBT) suffer from poor sensitivity, particularly with respect to detecting early stages, as well as low acceptance among the population. Preliminary data on the detection of fecal proteins like calprotectin and tumour-M2-PK indicated that they might have better performance characteristics than the gFOBTs. However, these tests also suffer from low sensitivity and poor specificity especially for detecting early lesions. Recently developed immunological tests (iFOBT) demonstrate a significantly higher sensitivity and specificity. iFOBTs use antibodies specific to human hemoglobulin and therefore are not affected by the necessity of dietary and drug restrictions that otherwise limit the use of gFOBTs. At present iFOBTs seem to be the most cost-effective approach for non-invasive CRC screening. The analysis of fecal DNA represents an emerging new field for early detection of colorectal neoplasia. Small trials of multitarget assays demonstrated a sensitivity for CRC of 62 to 91% and a sensitivity for adenomas of 26 to 73%. The specificity of these assays is high ranging from 93 to 100%. The major drawback of fecal DNA testing, compared with other fecal colorectal cancer screening tests, is the unacceptable high cost.

Fecal M2-pyruvate kinase (M2-PK): a novel marker of intestinal inflammation

BACKGROUND

Surrogate markers of bowel inflammation are increasingly being recognized as important, not only as markers of disease activity in inflammatory bowel disease (IBD) but also to differentiate irritable bowel syndrome (IBS) from IBD. The dimeric M2-isoform of pyruvate kinase (M2-PK) has been reported to be elevated in fecal specimens from colorectal cancer (CA) patients, but its role in IBD is unknown. This study investigated the usefulness of fecal M2-PK in cohorts of patients with IBD, IBS, and CA.

METHODS

Stool samples were obtained for calprotectin and M2-PK measurements in patients with previously diagnosed IBD or new patients being investigated for lower gastrointestinal (GI) symptoms in a UK university hospital. Other investigations were performed as directed by the investigating physician and patients with known IBD were assessed for disease activity by a physician global assessment, Harvey-Bradshaw index (HBI), or endoscopic grading.

RESULTS

Fecal M2-PK and calprotectin measurements were obtained for 148 patients: 50 with ulcerative colitis (UC); 31 with Crohn's disease (CD), 43 with irritable bowel syndrome/functional bowel disorders (IBS); 7 with colorectal CA, and 17 with miscellaneous conditions (excluded from the analysis). Median M2-PK values (U/mL) were significantly elevated in UC: 20.0 (95% confidence interval [CI] 5.4-69.0, P < 0.0001), CD: 24.3 (95% CI 6.4-44.0, P < 0.0001), and CA: 7.0 (95% CI 4.3-88.0, P < 0.0006) compared to IBS: 0.1 (95% CI 0.0-3.2). There was a strong linear correlation of M2-PK with calprotectin levels. A predetermined cutoff level of 3.7 U/mL for a normal M2-PK test produced a sensitivity, specificity, and positive predictive value (PPV) of 73%, 74%, and 89%, respectively, for organic disease. Furthermore, M2-PK levels were significantly elevated in active, compared to inactive, disease for CD (30 versus 0.55 U/mL, P < 0.005) and UC (40 versus 1.2 U/mL, P = 0.006), respectively.

CONCLUSIONS

Fecal M2-PK is elevated in IBD as well as in CA patients and is a sensitive and relatively specific marker for organic GI pathology, with a PPV of 89%. Furthermore, it appears to be a potentially valuable, noninvasive marker of disease activity in IBD.

Proteomic analysis reveals metabolic changes during yeast to hypha transition in Yarrowia lipolytica

Fungal dimorphism is important for survival in different environments and has been related to virulence. The ascomycete Yarrowia lipolytica can grow as yeast, pseudomycelial or mycelial forms. We have used a Y. lipolytica parental strain and a Deltahoy1 mutant, which is unable to form hypha, to set up a model for dimorphism and to characterize in more depth the yeast to hypha transition by proteomic techniques. A two-dimensional gel electrophoresis (2-DE) based differential expression analysis of Y. lipolytica yeast and hyphal cells was performed, and 45 differentially expressed proteins were detected; nine with decreased expression in hyphal cells were identified. They corresponded to the S. cerevisiae homologues of Imd4p, Pdx3p, Cdc19, Sse1p, Sol3p, Sod2p, Xpt1p, Mdh1p and to the unknown protein YALIOB00924g. Remarkably, most of these proteins are involved in metabolic pathways, with four showing oxidoreductase activity. Furthermore, taking into account that this is the first report of 2-DE analysis of Y. lipolytica protein extracts, 35 more proteins from the 2D map of soluble yeast proteins, which were involved in metabolism, cell rescue, energy and protein synthesis, were identified.

Tumor pyruvate kinase isoenzyme type M2 and immunochemical fecal occult blood test: performance in screening for colorectal cancer

OBJECTIVES

Immunochemical fecal occult blood test (FOBT) and determination of tumor pyruvate kinase isoenzyme type M2 (TuM2-PK) in stool samples may be valuable new screening tools for colorectal cancer (CRC). The aim of this study was to compare the accuracy of fecal TuM2-PK testing with immunochemical FOBT in patients with CRC or adenomas.

METHODS

A total of 52 patients with CRC were analyzed, 47 with colorectal adenomas, and 63 matched controls with a normal colonoscopy. Nineteen additional patients with inflammatory bowel disease were tested to determine influence of inflammation. Stool samples were analyzed with two immunochemical FOBTs, Immo-care and OC-Light, and with a commercial enzyme-linked immunosorbent assay for TuM2-PK.

RESULTS

In patients with CRC, the sensitivity of TuM2-PK, Immo-care and OC-Light was respectively 85, 92 and 94%. In patients with adenomas, the sensitivity was respectively 28, 40 and 34%. Specificity for these tests was 90% for TuM2-PK and 97% for both immunochemical FOBTs. All tests showed a high positivity rate in patients with inflammatory bowel disease (79% for TuM2-PK and Immo-care, and 89% for OC-Light).

CONCLUSION

Both immunochemical FOBTs appear valuable and are sensitive tests for CRC screening. TuM2-PK does not have supplemental value for screening for CRC because of a lower sensitivity and specificity. None of these tests is sensitive enough for detection of advanced adenomas. Patients with inflammatory bowel disease should be excluded from CRC screening when using immunochemical FOBT or TuM2-PK.