Analysis of cysteine glutathionylation in hemoglobin of gastric cancer patients using nanoflow liquid chromatography/triple‐stage mass spectrometry

e14635 Background: Clinicopathological characteristics of gastric cancer patients strongly depend on histological type. In contrast with gene and protein expressions, metabolic properties of intestinal- and diffuse-type gastric cancer have been largely unknown. Here, we conducted metabolome analysis of paired non-tumor and tumor gastric tissues by using capillary electrophoresis and liquid chromatography combined with time-of-flight mass spectrometry (CE- and LC-TOFMS, respectively) in order to metabolomically characterize non-tumors (NTs), intestinal-type tumors (ITs), and diffuse-type tumors (DTs). Methods: Tumor and surrounding non-tumor tissues were surgically excised pair-wise from 27 gastric cancer patients (18 ITs and 9 DTs) who underwent gastrectomy at our institution between February and May 2011. Following tissue homogenization and metabolite extraction, we measured 254 and 138 metabolites, respectively, by CE-TOFMS and LC-TOFMS. Results: Metabolomic profiles of tumor tissues, especially ITs, were well-distinguished from those of NTs: Lactate and most glycolytic intermediate levels in ITs were significantly higher than those in NTs, which reaffirms the Warburg effect of cancer, but the significance was lesser in DTs. Levels of all the measured amino acids were significantly higher in ITs and relatively higher in DTs than in NTs, showing high capacities of cancer cells for protein synthesis. Although levels of ATP, GTP, and energy charge in ITs and DTs were lower than those in NTs, purine contents were rather higher in the tumors than in NTs, which may support their high demand for DNA replication. Moreover, reduced glutathione in DTs were the lowest among others, implying their potential vulnerability against oxidative stress. Conclusions: Metabolomic profiles of NTs, ITs, and DTs were discriminated by CE- and LC-TOFMS analyses: Considerably high lactate, amino acid, and purine levels highlighted the metabolome of tumors, especially of ITs. Relatively low energy and redox statuses of DTs, however, could be targeted for developing more effective cancer therapeutics.

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Quantitative proteomic analysis of TUBB3 to identify gastric cancer patients who may benefit from docetaxel: A reevaluation of the ITACA-S trial.

Journal of Clinical Oncology ◽

10.1200/jco.2017.35.4_suppl.59 ◽

2017 ◽

Vol 35 (4_suppl) ◽

pp. 59-59 ◽

Cited By ~ 2

Author(s):

Fabiola Cecchi ◽

Daniel V.T. Catenacci ◽

Yuan Tian ◽

Rosalba Miceli ◽

Filippo Pietrantonio ◽

...

Keyword(s):

Mass Spectrometry ◽

Gastric Cancer ◽

Cancer Patients ◽

Proteomic Analysis ◽

Limit Of Detection ◽

Selected Reaction Monitoring ◽

Rank Test ◽

Class Iii ◽

Quantitative Proteomic Analysis ◽

Gastric Cancer Patients

59 Background: Chemotherapy (CTX) becomes targeted therapy when biomarkers can predict a patient’s response. A relationship between resistance to taxanes and overexpression of class III b-tubulin (TUBB3) has been suggested by small clinical studies, but not confirmed in randomized trials. The Intergroup Trial of Adjuvant CTX in Adenocarcinoma of the Stomach (ITACA-S) evaluated the survival advantage of postoperative sequential CTX with FOLFIRI followed by docetaxel plus cisplatin in comparison to monotherapy with 5-FU/LV in patients with radically resected gastric cancer (N = 1106). The results showed no difference in survival between the two CTX arms. In a random subset of patients (N = 247) from the ITACA-S trial, we applied mass spectrometry-based proteomics to assess the role of TUBB3 as a predictive biomarker for response to taxane-containing therapy. Methods: Archived tumor tissues were microdissected and solubilized for proteomic analysis. TUBB3 and 44 other protein biomarkers were quantified using a mass spectrometry-based selected reaction monitoring assay. A predetermined TUBB3 cutoff of 700 amol/µg was based on the assay’s limit of detection. The Mantel-Cox log-rank test was used for survival comparisons. Results: Among patients treated with taxane-containing CTX (n = 125), those with TUBB3 levels below the cutoff had nearly twice the median overall survival (OS) as patients with TUBB3 levels above the cutoff (1566 vs. 801 days, p = 0.0282). TUBB3 levels made no statistical difference in survival among patients who did not receive taxane. Of note, among patients with high TUBB3 levels ( > 700 amol), those treated without taxane-containing CTX survived far longer than patients in the taxane arm (OS = 1991 vs 801 days, p = 0.048). Conclusions: Quantitative proteomic analysis of TUBB3 expression identified a subset of gastric cancer patients who benefitted from the addition of docetaxel to adjuvant CTX. Patients with high TUBB3 expression levels had worse outcomes on a taxane-containing regimen than on CTX without taxane. Personalized CTX based on the TUBB3 biomarker is promising and warrants further validation. Clinical trial information: NCT01989858.

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Elevated Levels of Oxidative Nucleic Acid Modification Markers in Urine From Gastric Cancer Patients: Quantitative Analysis by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

Frontiers in Chemistry ◽

10.3389/fchem.2020.606495 ◽

2020 ◽

Vol 8 ◽

Author(s):

Qin Chen ◽

Yiqiu Hu ◽

Zhihao Fang ◽

Minfeng Ye ◽

Jingqing Li ◽

...

Keyword(s):

Mass Spectrometry ◽

Gastric Cancer ◽

Nucleic Acid ◽

Cancer Patients ◽

Ultra Performance Liquid Chromatography ◽

Tandem Mass ◽

Healthy Controls ◽

Chromatography Tandem Mass Spectrometry ◽

Liquid Chromatography Tandem Mass ◽

Gastric Cancer Patients

Oxidative nucleic acid modifications have attracted increasing attention in recent years since they have been found to be related to a number of diseases including cancer. 8-Hydroxy-2′-deoxyguanosine (8-OHdG) and 8-hydroxyguanosine (8-OHG) are the typical markers of oxidative modification of DNA and RNA, respectively, and they are emerging biomarkers for the early detection of diseases. Urine is a favored biofluid for biomarker discovery due to its noninvasiveness to patients. Accurate quantification of these oxidative nucleic acid modifications still has challenges because their amounts in urine are very low and the interferences in urine samples are complicated. Herein, we developed and validated an accurate and robust solid-phase extraction (SPE) coupled with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous quantification of these oxidative nucleic acid modifications in human urine. Stable isotope dilution strategy was utilized and the method shows good precision on intraday and interday measurements. Meanwhile, recovery was satisfactory by utilizing the Oasis hydrophilic–lipophilic balance (HLB) cartridge for sample pretreatment at three spiked levels. We successfully quantified urinary 8-OHdG and 8-OHG from 60 gastric cancer patients and 70 healthy controls by using this method. The measured contents of 8-OHdG and 8-OHG in urine from gastric cancer patients are both increased, compared with those in urine from healthy controls, indicating these oxidative nucleic acid modifications could act as potential non-invasive markers for early diagnosis of gastric cancer. Moreover, the present study will stimulate investigations of the effects of oxidative stress and nucleic acid modifications on the initiation and progression of gastric cancer.

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