Tumor Cell Content and RNA Integrity of Surgical Tissues from Different Types of Tumors and Its Correlation with Ex Vivo and In Vivo Ischemia
Tissues from tumor patients are important resources for promoting cancer research, and therefore many biobanks have been established to collect tumor tissues; however, the quality of tumor tissues after surgical resection has not been well documented.
A total of 896 cases of tissues from 12 types of tumors were chosen for this study. First, histopathological examination was conducted to evaluate the tumor cell content; second, microchip electrophoresis was used to determine the RNA integrity number (RIN) in 466 cases of tissues with a tumor cell content ≥ 75%; and, finally, a correlation test was used to analyze the effect of ischemia on RNA integrity in 384 cases of tissues with a recorded ischemia time.
Tumor tissues from 12 different organs had different tumor cell contents and RNA integrity. The liver had the highest percentage (69.7%) of tissue samples with a tumor cell content ≥ 75%, and the highest percentage (96%) of samples with an RIN ≥ 7. RNA integrity was not correlated with limited ex vivo ischemia time (5–60 min) in any of the 12 types of tumors. In contrast, a significant correlation with in vivo ischemia time was observed in several types of tumors.
Not every sample of excised tumor tissue has a sufficient amount of tumor cells and enough RNA integrity. In vivo ischemia has a more significant influence on RNA integrity, and tumor tissues have different tolerances to pre-analytical variables. Those conducting translational research should pay attention to pre-analytical variables when collecting and utilizing tumor tissues.
This work was supported by the National Science Fund for Distinguished Young Scholars (81325018), the Key Project for International Cooperation and Exchange of the National Natural Science Foundation of China (81220108022), the National Key Research and Development Program (2016YFC1302704), and Guangdong Special Support Programs for high-level personnel (2014TX01R201).
No potential conflicts of interest were disclosed.
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