We investigated the alterations in the plasma concentrations of energy-balance-related metabolites in patients with lung (LC) or head & neck (HNC) cancer and the changes on these parameters induced by radiotherapy. The study was conducted in 33 patients with non-small cell LC and 28 patients with HNC. We analyzed the concentrations of 17 metabolites involved in glycolysis, citric acid cycle and amino acid metabolism using targeted gas chromatography coupled to quadrupole time-of-flight mass spectrometry. For comparison, a control group of 50 healthy individuals was included in the present study. Patients with LC or HNC had significant alterations in the plasma levels of several energy-balance-related metabolites. Radiotherapy partially normalized these alterations in patients with LC, but not in those with HNC. The measurement of plasma glutamate concentration was an excellent predictor of the presence of LC or HNC, with sensitivity >90% and specificity >80%. Also, associations with disease prognosis were observed with plasma glutamate, amino acids and β-hydroxybutyrate concentrations. SIGNIFICANCE: This study analyzed the changes produced in the plasma concentrations of energy-balance-related metabolites in patients with lung cancer or head and neck cancer. The results obtained identified glutamate as the parameter with the highest discrimination capacity between patients and the control group. The relationships between various metabolites and clinical outcomes were also analyzed. These results extend the knowledge of metabolic alterations in cancer, thus facilitating the search for biomarkers and therapeutic targets.

中文翻译：

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肺癌或头颈部癌症患者血浆中能量平衡相关代谢物的血浆浓度变化：放射疗法的影响。

我们研究了肺癌（LC）或头颈癌（HNC）患者血浆中能量平衡相关代谢物的血浆浓度变化以及放疗引起的这些参数的变化。该研究在33例非小细胞LC患者和28例HNC患者中进行。我们使用靶向气相色谱与四极杆飞行时间质谱联用，分析了参与糖酵解，柠檬酸循环和氨基酸代谢的17种代谢物的浓度。为了进行比较，本研究中包括了50个健康个体的对照组。患有LC或HNC的患者血浆中几种能量平衡相关代谢产物的水平发生了显着变化。放疗使LC患者的这些改变部分正常化，但对于HNC患者则没有。血浆谷氨酸浓度的测量是LC或HNC存在的极好的预测指标，灵敏度> 90％，特异性> 80％。此外，还观察到血浆谷氨酸，氨基酸和β-羟基丁酸酯浓度与疾病预后的关系。重要性：这项研究分析了肺癌或头颈癌患者血浆中能量平衡相关代谢产物的血浆浓度变化。获得的结果鉴定出谷氨酸为患者和对照组之间具有最高区分能力的参数。还分析了各种代谢物与临床结果之间的关系。这些结果扩展了癌症中代谢改变的知识，从而促进了对生物标志物和治疗靶标的搜索。