Protein precipitation coupled to paper spray with a tube for one-step analysis of blood.

RATIONALE: Accurate measurement of trace compounds in blood samples is important in clinical diagnosis and life science. Ambient ionization mass spectrometry, however, suffers from the matrix effect when dealing with complex samples such as blood. Therefore, it is important to reduce the matrix effects in blood samples. METHODS: A low-cost and disposable Teflon tube was used as a platform to precipitate the protein in blood. The analytes are extracted into organic solvent, and the precipitated protein can be adsorbed by the chromatography paper inserted. Therefore, the Teflon tube after precipitation can be directly subjected to paper spray ionization mass spectrometry, achieving one-step analysis of blood. RESULTS: High sensitivity and satisfactory stability were achieved for pharmaceuticals, acids, and endogenic metabolites in blood. The absolute signal intensities of characteristic product ions of the tested analytes were 8-20 times higher after protein precipitation than those obtained using paper spray. Detection limits and quantitative performance were evaluated for three drugs: carbamazepine, metformin, and tioconazole. In addition, the limits of detection and quantitation were improved 9-14- and 8-12-fold, respectively. CONCLUSIONS: Protein precipitation coupled to paper spray with a tube and then to mass spectrometry was successfully achieved and applied in the one-step analysis of trace compounds in blood samples. The experimental results showed that this method was sensitive, stable, convenient, and economic for the direct analysis of blood.

Nomogram based on CMTM6 expression and clinical characteristics to predict postoperative overall survival in patients with hepatocellular carcinoma.

BACKGROUND: The purpose of this study was to investigate the expression of CMTM6 in HCC tissues and its prognostic value, and to try to develop a nomogram prognostic model based on CMTM6. METHODS: In this retrospective study, immunohistochemical (IHC) staining was performed in 178 patients who underwent radical hepatectomy in the same surgical team. R software was used to construct the nomogram model. The Bootstrap sampling method was used for internal validation. RESULTS: CMTM6 is significantly expressed in HCC tissues and is closely associated with decreased overall survival (OS). PVTT (HR = 6.2, 95% CI: 3.06 12.6, P<0.001), CMTM6 (HR=2.30, 95% CI: 1.27 4.0, P=0.006) and MVI (HR=10.8, 95% CI: 4.19-27.6, P<0.001) were independent predictors of OS. The nomogram combined with CMTM6, PVTT and MVI was more predictive than the traditional TNM scoring system, and the prediction effects of 1-year and 3-year OS were accurate. CONCLUSIONS: The prognosis of a patient may be predicted using high levels of CMTM6 expression in HCC tissues, and the nomogram model including CMTM6 expression has the best predictive ability.

High expression of CMTM6 is a risk factor for poor prognosis of gastrointestinal tumors: A meta-analysis.

Previous research on the link between CMTM6 expression dysregulation and tumor prognosis has been conflicting. In this study, the predictive effect of CMTM6 in malignant tumors was carefully evaluated using meta-analysis. The literature on the relationship between CMTM6 expression level and malignant tumor prognosis was searched in PubMed, Medline, Embase, and Web of Science databases until April 2021. Data were extracted from eligible studies and analyzed using RevMan5.3 and STATA 12.0 software. The HR and 95%CI were used to analyze the link between CMTM6 expression and OS. And the correlation between CMTM6 expression and clinicopathological features LNM and DM was evaluated by OR and 95%CI. Literature screening eventually included 12 studies involving 2133 patients with malignant tumors. High CMTM6 expression was found to be strongly linked with shorter OS and PFS in cancer patients (HR = 1.84,95%CI: 1.28-2.63, P = 0.001). High CMTM6 expression in gastrointestinal cancers was found to be significantly related with a shorter OS (HR = 2.21, 95%CI: 1.75-2.78, P 0.001). PFS was observed to be related with high CMTM6 expression in cancer patients (HR = 2.029, 95%CI: 1.263-3.26, P = 0.003). Meanwhile, high CMTM6 expression was highly associated to LNM (OR = 1.64, 95%CI: 1.02-2.64, P = 0.043) and DM (OR = 4.07, 95%CI: 1.73-9.56, P = 0.001). However, the expression level of CMTM6 in non-gastrointestinal tumors was not statistically significant with OS or LNM. High CMTM6 expression in gastrointestinal cancers is linked to shorter OS and PFS, as well as LNM and DM, suggesting that high CMTM6 expression could be employed as a new diagnosis for poor prognosis and metastasis.