Application of PAF in the preparation of a kit for diagnosing metastasis of esophageal squamous cell carcinoma

Abstract

The present invention relates to the field of biomarker diagnosis. Specifically, the present invention relates to an application of PAF (Platelet-Activating Factor) in the preparation of a kit for diagnosing esophageal squamous cell carcinoma metastasis. According to the experimental results in the embodiments of the present invention, by detecting the expression level of PAF in the plasma of patients with esophageal squamous cell carcinoma, it is possible to effectively diagnose whether the patients have esophageal squamous cell carcinoma metastasis (AUC=0.906).

Description

Technical Field

[0001] The present invention relates to the field of medical diagnosis, and in particular, to an application of PAF in preparing a kit for diagnosing metastasis of esophageal squamous cell carcinoma. Background Art

[0002] Esophageal squamous cell carcinoma (ESCC) is very prone to metastasis, mainly through lymph node metastasis and hematogenous metastasis. At present, the five-year clinical survival rate of esophageal cancer is extremely low, which is mainly closely related to ESCC metastasis. Therefore, the discovery of markers for diagnosing ESCC metastasis is the key to improving the overall efficacy of ESCC patients.

[0003] Platelet-activating factor (PAF) is a potent pro-inflammatory small molecule metabolite. The earliest studies found that PAF plays an important role in the body's immune regulation and vascular homeostasis. In oncology research, PAF can promote the progression of solid tumors such as lung cancer, various gastrointestinal tumors, and gliomas by activating multiple signaling pathways, such as STAT3 and NF-κB.

[0004] Many tumors have an insidious onset, lack of clinically specific manifestations, and cannot be systematically evaluated through a combination of multiple testing methods. This results in cancer patients being in the late stage when they seek medical treatment, and having a poor prognosis. Plasma testing can directly test biomarkers through blood samples obtained through minimally invasive methods. It is convenient for testing, low cost, high efficiency, and has excellent application prospects. However, so far, there are no biomarkers that can be used for non-invasive testing to diagnose whether esophageal squamous cell carcinoma has metastasized. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the related art, and provides an application of PAF in preparing a kit for diagnosing metastasis of esophageal squamous cell carcinoma. Specifically, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a use of PAF in preparing a kit for diagnosing metastasis of esophageal squamous cell carcinoma, wherein the kit comprises a reagent for detecting the concentration of PAF in plasma or tumor tissue of esophageal cancer patients.

[0007] In one embodiment, the esophageal squamous cell carcinoma metastasis is lymphatic metastasis.

[0008] In a preferred embodiment, the kit is used by detecting the PAF concentration in the patient's plasma. When the PAF concentration is higher than 4.2 ng / mL, the esophageal squamous cell carcinoma patient is at high risk of lymph node metastasis, and when the PAF concentration is less than or equal to 4.2 ng / mL, the esophageal squamous cell carcinoma patient is at low risk of lymph node metastasis. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0010] Figure 1 It is the ROC curve diagram. DETAILED DESCRIPTION

[0011] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0012] Example 1 PAF is highly expressed in local tumor tissue and plasma of patients with esophageal squamous cell carcinoma metastasis, and the expression is positively correlated

[0013] 1. Sample extraction:

[0014] A total of 24 patients with non-metastatic esophageal squamous cell carcinoma and 28 patients with lymph node metastasis (from Peking University Cancer Hospital, all of whom had signed informed consent) were enrolled. Local tumor tissue and plasma samples were extracted from the patients, and the tumor tissue was placed in phosphate buffer for lysis and protein extraction.

[0015] Add samples sequentially to the PAF ELISA 96-well plate (Abcam, Catalog No.: ab287801), seal and incubate at 37 °C for 1 hour. After incubation, discard the sample and wash it repeatedly with cleaning solution 5 times. Add the biotin-linked antibody (Abcam, Catalog No.: ab287801) to the 96-well plate (100 μL / well), shake and incubate at room temperature for 1 hour, wash repeatedly with cleaning solution and discard. Add reaction substrate to each well, add reaction stop solution at room temperature in the dark, and measure the absorbance value at 450 nm using an ELISA reader.

[0016] The expression differences of PAF in local tumor tissues and plasma samples of 28 metastatic and 24 non-metastatic groups were compared (Table 1), and the correlation of PAF expression in plasma and local tumor tissues of the 28 metastatic groups was observed by Spearman test.

[0017] Table 1 Comparison of plasma PAF concentrations between non-metastatic and metastatic patients

[0018]

[0019] The results are shown in Table 1. Compared with non-metastatic patients, PAF was highly expressed in the plasma and tumor tissues of patients with esophageal squamous cell carcinoma metastasis (P < 0.001). For metastatic patients, PAF expression in both plasma and tumor samples was positively correlated.

[0020] Based on the above sample set, a ROC curve was created to determine the accuracy of PAF as a plasma marker. The model training data was used to calculate the true positive rate and false positive rate at each possible threshold. The ROC curve was drawn with the false positive rate as the horizontal axis and the true positive rate as the vertical axis. Each point represents a specific threshold, and these points are connected to form the ROC curve. The AUC value was calculated to quantify the performance of the model. According to the ROC curve results ( Figure 1 ), PAF's diagnostic power for esophageal squamous cell carcinoma metastasis AUC=0.906, indicating that the PAF content in the plasma of patients with non-metastatic / metastatic esophageal squamous cell carcinoma can effectively judge the metastasis of esophageal squamous cell carcinoma. Among them, the lowest value of PAF concentration in the plasma of 24 patients with non-lymphatic metastasis of esophageal squamous cell carcinoma was 0.857ng / mL, and the highest value was 4.155ng / mL. The lowest value of PAF concentration in the plasma of 28 patients with lymphatic metastasis of esophageal squamous cell carcinoma was 4.555ng / mL, and the highest value was 9.174ng / mL. Therefore, we use the PAF plasma concentration of 4.2ng / mL as the risk index for lymphatic metastasis, that is, esophageal squamous cell carcinoma patients with PAF plasma concentration higher than 4.2ng / mL are high-risk patients for lymphatic metastasis, and esophageal squamous cell carcinoma patients with PAF plasma concentration less than or equal to 4.2ng / mL are low-risk patients for lymphatic metastasis.

[0021] Example 2 Validation of the effectiveness of PAF as a biomarker for detecting metastasis of esophageal squamous cell carcinoma

[0022] In order to verify the effectiveness of PAF as a biomarker for detecting esophageal squamous cell carcinoma metastasis, we re-enrolled 32 non-metastatic patients and 57 patients with lymph node metastasis (as a validation set, from Peking University Cancer Hospital, all of whom had signed informed consent), analyzed the samples of the validation set patients using the method and model described in Example 1 above, and compared the analysis results with the clinical expert judgment results:

[0023] Table 2 Comparison of patients' plasma PAF concentration and judgment results

[0024]

[0025]

[0026] From the above results, it can be seen that the use of PAF as a biomarker for the judgment of esophageal squamous cell carcinoma metastasis is relatively accurate, with a consistency of more than 97.75% with expert judgment.

[0027] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A use of PAF in the preparation of a kit for diagnosing metastasis of esophageal squamous cell carcinoma, characterized in that: The kit comprises a reagent for detecting the PAF concentration in the plasma of patients with esophageal squamous cell carcinoma, wherein the metastasis of the esophageal squamous cell carcinoma is lymphatic metastasis.

2. The use according to claim 1, characterized in that The kit is used by detecting the PAF concentration in the patient's plasma. When the PAF concentration is higher than 4.2 ng / mL, the esophageal squamous cell carcinoma patient is at high risk of lymph node metastasis, and when the PAF concentration is less than or equal to 4.2 ng / mL, the esophageal squamous cell carcinoma patient is at low risk of lymph node metastasis.

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