High-Density, Targeted Monitoring of Tyrosine Phosphorylation Reveals Activated Signaling Networks in Human Tumors.

Tyrosine phosphorylation (pTyr) plays a pivotal role in signal transduction and is commonly dysregulated in cancer. As a result, profiling tumor pTyr levels may reveal therapeutic insights critical to combating disease. Existing discovery and targeted mass spectrometry-based methods used to monitor pTyr networks involve a tradeoff between broad coverage of the pTyr network, reproducibility in target identification across analyses, and accurate quantification. To address these limitations, we developed a targeted approach, termed "SureQuant pTyr," coupling low input pTyr enrichment with a panel of isotopically labeled internal standard peptides to guide data acquisition of low-abundance tyrosine phosphopeptides. SureQuant pTyr allowed for reliable quantification of several hundred commonly dysregulated pTyr targets with high quantitative accuracy, improving the robustness and usability of targeted mass spectrometry assays. We established the clinical applicability of SureQuant pTyr by profiling pTyr signaling levels in human colorectal tumors using minimal sample input, characterizing patient-specific oncogenic-driving mechanisms. While in some cases pTyr profiles aligned with previously reported proteomic, genomic, and transcriptomic molecular characterizations, we highlighted instances of new insights gained using pTyr characterization and emphasized the complementary nature of pTyr measurements with traditional biomarkers for improving patient stratification and identifying therapeutic targets. The turn-key nature of this approach opens the door to rapid and reproducible pTyr profiling in research and clinical settings alike and enables pTyr-based measurements for applications in precision medicine. SIGNIFICANCE: SureQuant pTyr is a mass spectrometry-based targeted method that enables sensitive and selective targeted quantitation of several hundred low-abundance tyrosine phosphorylated peptides commonly dysregulated in cancer, including oncogenic signaling networks.

Hemorrhoid Energy Therapy for Treatment of Deep Chronic Anal Fissures.

Energy therapy is a well-known, minimally invasive treatment for internal hemorrhoids. This treatment has not yet been studied in anal fissures refractory to medical therapy. Anal fissures, such as hemorrhoids, can disrupt the quality of life for patients. Currently, nonsurgical treatments available for anal fissures are only supportive measures. Definitive for chronic anal fissures refractory to medical therapy is internal sphincterotomy. This treatment has chances of relapse and a risk of anal incontinence. We propose the use of hemorrhoid energy therapy with bipolar cautery as a safer, less invasive, and effective therapy for recurrent anal fissures refractory to conservative management.

Low-dose vitamin K to augment anticoagulation control.

STUDY OBJECTIVES: To determine the effect of daily low-dose oral vitamin K supplementation on reducing variations in the international normalized ratios (INRs) in patients taking warfarin. DESIGN: Retrospective analysis. SETTING: Anticoagulation clinic in a large, private-practice hematology group. PATIENTS: Eight motivated patients (three men, five women), aged 45-79 years, receiving anticoagulant therapy with warfarin, whose INRs had been fluctuating for reasons not associated with identifiable changes in diet, warfarin dosage, activity level, illness, or changes in drug therapy. INTERVENTION: Daily supplementation with oral vitamin K, starting with 100 microg/day MEASUREMENTS AND MAIN RESULTS: Anticoagulation providers monitored INR responses; all documented INR values were included in the analysis, even those intentionally allowed outside the therapeutic range when dosages were adjusted for procedures. After dietary vitamin K supplementation, INR fluctuations diminished in nearly all patients. Overall, a significant decrease was noted in the INR standard deviation (p<0.05), and more INRs were in the therapeutic range after the start of supplementation. Allowing for small fluctuations on either side of the target range, the number of INRs within 0.2 units of the target range increased from 32% to 57% (relative increase 76%). Time in range also increased by a similar degree. CONCLUSION: Supplementation with daily low-dose oral vitamin K significantly increased the number of INRs in range as well as the time in range, and decreased INR fluctuation in this small series of selected patients.