Independent Validation and Assay Standardization of Improved Metabolic Biomarker Signature to Differentiate Pancreatic Ductal Adenocarcinoma From Chronic Pancreatitis

BACKGROUND & AIMS

Pancreatic ductal adenocarcinoma cancer (PDAC) is a highly lethal malignancy requiring efficient detection when the primary tumor is still resectable. We previously developed the MxPancreasScore comprising 9 analytes and serum carbohydrate antigen 19-9 (CA19-9), achieving an accuracy of 90.6%. The necessity for 5 different analytical platforms and multiple analytical runs, however, hindered clinical applicability. We therefore aimed to develop a simpler single-analytical run, single-platform diagnostic signature.

METHODS

We evaluated 941 patients (PDAC, 356; chronic pancreatitis [CP], 304; nonpancreatic disease, 281) in 3 multicenter independent tests, and identification (ID) and validation cohort 1 (VD1) and 2 (VD2) were evaluated. Targeted quantitative plasma metabolite analysis was performed on a liquid chromatography-tandem mass spectrometry platform. A machine learning-aided algorithm identified an improved (i-Metabolic) and minimalistic metabolic (m-Metabolic) signatures, and compared them for performance.

RESULTS

The i-Metabolic Signature, (12 analytes plus CA19-9) distinguished PDAC from CP with area under the curve (95% confidence interval) of 97.2% (97.1%-97.3%), 93.5% (93.4%-93.7%), and 92.2% (92.1%-92.3%) in the ID, VD1, and VD2 cohorts, respectively. In the VD2 cohort, the m-Metabolic signature (4 analytes plus CA19-9) discriminated PDAC from CP with a sensitivity of 77.3% and specificity of 89.6%, with an overall accuracy of 82.4%. For the subset of 45 patients with PDAC with resectable stages IA-IIB tumors, the sensitivity, specificity, and accuracy were 73.2%, 89.6%, and 82.7%, respectively; for those with detectable CA19-9 >2 U/mL, 81.6%, 88.7%, and 84.5%, respectively; and for those with CA19-9 <37 U/mL, 39.7%, 94.1%, and 76.3%, respectively.

CONCLUSIONS

The single-platform, single-run, m-Metabolic signature of just 4 metabolites used in combination with serum CA19-9 levels is an innovative accurate diagnostic tool for PDAC at the time of clinical presentation, warranting further large-scale evaluation.

Identification and validation of a multivariable prediction model based on blood plasma and serum metabolomics for the distinction of chronic pancreatitis subjects from non-pancreas disease control subjects

OBJECTIVE

Chronic pancreatitis (CP) is a fibroinflammatory syndrome leading to organ dysfunction, chronic pain, an increased risk for pancreatic cancer and considerable morbidity. Due to a lack of specific biomarkers, diagnosis is based on symptoms and specific but insensitive imaging features, preventing an early diagnosis and appropriate management.

DESIGN

We conducted a type 3 study for multivariable prediction for individual prognosis according to the TRIPOD guidelines. A signature to distinguish CP from controls (n=160) was identified using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry on ethylenediaminetetraacetic acid (EDTA)-plasma and validated in independent cohorts.

RESULTS

A Naive Bayes algorithm identified eight metabolites of six ontology classes. After algorithm training and computation of optimal cut-offs, classification according to the metabolic signature detected CP with an area under the curve (AUC) of 0.85 ((95% CI 0.79 to 0.91). External validation in two independent cohorts (total n=502) resulted in similar accuracy for detection of CP compared with non-pancreatic controls in EDTA-plasma (AUC 0.85 (95% CI 0.81 to 0.89)) and serum (AUC 0.87 (95% CI 0.81 to 0.95)).

CONCLUSIONS

This is the first study that identifies and independently validates a metabolomic signature in plasma and serum for the diagnosis of CP in large, prospective cohorts. The results could provide the basis for the development of the first routine laboratory test for CP.

Plasma Metabolome Profiling Identifies Metabolic Subtypes of Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest cancers. Developing biomarkers for early detection and chemotherapeutic response prediction is crucial to improve the dismal prognosis of PDAC patients. However, molecular cancer signatures based on transcriptome analysis do not reflect intratumoral heterogeneity. To explore a more accurate stratification of PDAC phenotypes in an easily accessible matrix, plasma metabolome analysis using MxP® Global Profiling and MxP® Lipidomics was performed in 361 PDAC patients. We identified three metabolic PDAC subtypes associated with distinct complex lipid patterns. Subtype 1 was associated with reduced ceramide levels and a strong enrichment of triacylglycerols. Subtype 2 demonstrated increased abundance of ceramides, sphingomyelin and other complex sphingolipids, whereas subtype 3 showed decreased levels of sphingolipid metabolites in plasma. Pathway enrichment analysis revealed that sphingolipid-related pathways differ most among subtypes. Weighted correlation network analysis (WGCNA) implied PDAC subtypes differed in their metabolic programs. Interestingly, a reduced expression among related pathway genes in tumor tissue was associated with the lowest survival rate. However, our metabolic PDAC subtypes did not show any correlation to the described molecular PDAC subtypes. Our findings pave the way for further studies investigating sphingolipids metabolisms in PDAC.

[Hepaticojejunostomy after pancreatic head resection - technical aspects for reconstruction of small and fragile bile ducts with T-tube drainage]

BACKGROUND

After pancreatic head resection the reconstruction of small and fragile bile ducts is technically demanding, resulting in more postoperative bile leaks. One option for the reconstruction is the placement of a T-tube drainage at the site of the anastomosis.

MATERIAL AND METHODS

Standard reconstruction after pancreatic head resection was an end-to-side hepaticojejunostomy with PDS 5.0, 15-25 cm distally from the pancreaticojejunostomy. For patients with a small bile duct diameter (≤ 5 mm) or a fragile bile duct wall the reconstruction was performed with PDS 6.0 and a T-tube drainage at the side of the anastomosis.

RESULTS

The reconstruction with a T-tube drainage at the site of the anastomosis is technically easy to perform and offers the opportunity for immediate visualisation of the anastomosis in the postoperative period by application of water soluble contrast medium. If a bile leak occurs, biliary deviation through the T-tube drainage can enable a conservative management without revisional laparotomy in selected patients. Whether or not a conservative management of postoperative bile leaks will lead to more bile duct strictures is a subject for further investigations.

CONCLUSION

A T-tube drainage at the site of the anastomosis can probably not prevent postoperative bile leaks from a difficult hepaticojejunostomy, but in selected patients it offers the opportunity for a conservative management resulting in less re-operations. Therefore we recommend the augmentation of a difficult hepaticojejunostomy with a T-tube drainage.

208 EFFECT OF TWO CATTLE EMBRYO CO-CULTURE SYSTEMS ON CALVING RATE

The objective of this study was to compare the calving rate after transfer of IVM/IVF/IVC embryos co cultured on both Vero and Vero/BRL cells (Duszewska 2000 Theriogenology 54, 1239–1247). Cumulus–oocyte complexes (COCs) were matured in TCM-199 supplemented with 10% FBS, 0.02 IU mL−1 FSH, 1 µg mL−1 17β-estradiol, 0.2 mM Na pyruvate, and 50 µg mL−1 gentamicin for 24 h at 38.5°C in 5% CO2. Spermatozoa were prepared by the swim-up procedure. COCs were fertilized in Fert-TALP supplemented with 6 mg/mL−1 fatty acid-free BSA, 0.2 mM Na pyruvate, 50 µg mL−1 gentamicin sulfate, 20 µM penicillamine, 10 µM hypotaurine, 1 µM epinephrine, and 2 µg/mL−1 heparin for 20 h at 38.5°C in 5% CO2. The zygotes were randomly allocated to one of the co-culture systems: Vero (2 × 103 cells in a 40-µL drop; 20 zygotes per drop), and Vero/BRL (1 × 103 Vero cells and 1 × 103 BRL cells in a 40-µL drop; 20 zygotes per drop). The zygotes from Vero and Vero/BRL were cultured for 168 h post-insemination in drops of Menezo B2 supplemented with 10% FBS until 144 h and from 144 h to 168 h without FBS, at 38.5°C in 5% CO2. Next, the blastocysts (Grade 1, according to IETS Manual) from Vero and Vero/BRL were transferred to recipients. The recipients were monitored daily for heat behavior, examined by ultrasound after 35 days and 65 days, and then observed monthly to confirm pregnancy. The results are presented in Table 1. Statistical significance was tested using the chi-square test. In spite of better development of cattle embryos on Vero/BRL cells than on Vero cells (P &lt; 0.05), a lower rate of calving was obtained after transfer of these embryos to recipients than for those on Vero cells (P &lt; 0.001). Higher loss of pregnancy after transfer of Vero/BRL embryos was observed in Days 35–65, which may indicate early fetal resorption. All calves were born naturally, healthy, and with normal weight. Table 1.Calving rate after transfer of embryos co-cultured on Vero cells and on Vero/BRL cells This work was supported by KBN Grant 2P06D05228.

Fecal incontinence: an up-to-date critical overview of surgical treatment options

BACKGROUND

Surgery is the last resort for patients suffering from severe fecal incontinence. The armamentarium of surgical options for this condition has increased impressively during the last decade. Nevertheless, this fact seems to make neither patients nor surgeons feel more comfortable. Treatment of fecal incontinence still remains a challenge to modern medicine due to many specific sides of this problem.

AIMS

This article gives an up-to-date overview of existing operative treatment options.

METHODS

An unbiased review of relevant literature was performed to assess the role of all methods of surgical treatment for fecal incontinence available nowadays.

RESULTS

Recent studies have shown poor late results after primary sphincter repair and low predictive value for most preoperative diagnostic tests. New surgical options such as artificial devices and electrically stimulated muscle transpositions are doomed by low success rates and unacceptably frequent complications. That is why current attention has focused on non- or minimally invasive therapies such as sacral nerve stimulation and temperature-controlled radio-frequency energy delivery to the anal canal. However, all these innovative techniques remain experimental till enough high-evidence data are gathered for their objective evaluation.

CONCLUSION

Careful and detailed preoperative assessment to exactly determine the etiology of incontinence and individual approach remain the cornerstones of surgical treatment of fecal incontinence nowadays.

Specific pathophysiological functions of JNK isoforms in the brain

We have investigated the effect of JNK1 ko, JNK2 ko, JNK3 ko, JNK2+3 ko and c-JunAA mutation on neuronal survival in adult transgenic mice following ischemia, 6-hydroxydopamine induced neurotoxicity, axon transection and kainic acid induced excitotoxicity. Deletion of JNK isoforms indicated the compartment-specific expression of JNK isoforms with 46-kDa JNK1 as the main phosphorylated JNK isoform. Permanent occlusion of the MCA significantly enlarged the infarct area in JNK1 ko, which showed an increased expression of JNK3 in the penumbra. Survival of dopaminergic neurons in the substantia nigra compacta (SNC) following intrastriatal injection of 6-hydroxydopamine was transiently improved in JNK3 ko and c-JunAA mice after 7 days, but not 60 days. Following transection of the medial forebrain bundle, however, JNK3 ko conferred persisting neuroprotection of axotomised SNC neurons. None of the JNK ko and c-JunAA mutation affected the survival of facial motoneurons following peripheral axotomy when investigated after 90 days. Finally, we determined the impact of JNK ko on the survival of animals and the degeneration of hippocampal neurons following kainic acid. JNK3 ko mice were substantially resistant against and survived kainic acid-induced seizures. JNK3 ko and JNK1 ko showed a nonsignificant tendency for decreased or increased death of hippocampal neurons, respectively. Surprisingly, the deletion of a single JNK isoform did not attenuate the immunocytochemical signal of phosphorylated c-Jun irrespective on the experimental set-up. This comprehensive study provides novel insights into the context-dependent physiological and pathological functions of JNK isoforms.