Identification of neutrophil-derived proteases and angiotensin II as biomarkers of cancer cachexia.

BACKGROUND

Cachexia is a metabolic disorder characterised by muscle wasting, diminished response to anti-cancer treatments and poor quality of life. Our objective was to identify blood-based biomarkers of cachexia in advanced cancer patients. Hence, we characterised the plasma cytokine and blood cell mRNA profiles of patients grouped in three cohorts: patients with cachexia, pre-cachexia (no cachexia but high CRP levels: ⩾ 5 mg l⁻¹) and no cachexia (no cachexia and CRP: < 5 mg l⁻¹).

METHODS

A total of 122 newly diagnosed cancer patients with seven cancer types were studied prior to their initial therapy. Plasma levels of 22 cytokines were quantified using the bio-plex technology. mRNAs isolated from whole blood and expression profiles were determined by the chip array technology and Ingenuity Pathway Analysis (IPA) software.

RESULTS

In comparison with non-cachectic individuals, both pre-cachectic and cachectic patients showed an increase (⩾ 1.5-folds) in mRNA expression of neutrophil-derived proteases (NDPs) and significantly elevated angiotensin II (Ang II) (P = 0.005 and P = 0.02, respectively), TGFβ1 (P = 0.042 and P < 0.0001, respectively) and CRP (both P < 0.0001) in the plasma. Moreover, cachectic patients displayed a significant increase in IL-6 (P = 0.005), IL-8 (P = 0.001) and absolute neutrophil counts (P = 0.007).

CONCLUSIONS

Ang II, TGFβ1, CRP and NDP are blood biomarkers for cancer cachexia. These findings contribute to early diagnosis and prevention of cachexia.