Prognostic and immunological significance of metastasis associated lung adenocarcinoma transcript 1 among different kinds of cancers

Abstract

LncRNAs belong to the type of noncoding RNA transcripts, which exceed 200 nucleotides in size. MALAT1 as one of the earlier identified lncRNAs in cancer is investigated by more and more scientific researchers. Expression, clinical significance and function of MALAT1 in pan-cancer exist as big difference. To detect the expression and clinical significance of MALAT1 gene precisely and comprehensively among different kinds of cancers, some classical databases such as GEPIA, TIMER, KM Plotter, and PrognoScan were fully applied. An immunological role of MALAT1 among different kinds of cancers was also determined in TIMER database. Our results showed that MALAT1 was differently expressed in different kinds of cancers using GEPIA, Oncomine, and TIMER databases to analyze. Especially, MALAT1 high RNA level was related to the early stage in lung and gastric cancer patients. MALAT1 expression was closely related to prognosis among different cancer patients. Furthermore, expression of MALAT1 was related to tumor immune cell infiltrating. Expression level of MALAT1 was also related to immune makers such as macrophage, T cell, NK cells, and so on. These findings indicate that MALAT1 could be a potential prognostic biomarker of some kinds of cancer and was significantly correlated with tumor-infiltrating immune cells in a wide variety of cancers.

Evaluation of the clinical significance of long non-coding RNA MALAT1 genetic variants in human lung adenocarcinoma

“…Intriguingly, the TCGA study revealed that patients with LADC who had low expression of MALAT1 had a considerably poorer prognosis than those who had high expression of EGFR wild-type (Figure 2B). Nevertheless, previous studies have shown that MALAT1 functions as an oncogene in cancer [55,56]; however, our data suggest that MALAT1 may have a tumor suppressor function in lung cancer cells which is consistent with previous result [33,57].…”

Non‐coding RNAs in cancer immunotherapy: Predictive biomarkers and targets

“…118 Interestingly, Malat1 was linked to regulatory immune cells infiltrating tumour and to the regulation of cytotoxic T cells, NK cells and macrophages in the TME. 119,120 Suppression of Malat1 significantly enhanced Th1 and Th2 differentiation and lowered levels of IL-10 immunosuppressive cytokine. 120 A study of chromatin-enriched lncRNAs revealed that Malat1 links with trans lncRNAs that boost RNA interac-tions at gene promoters.…”

“…Inhibition of Malat1 prevented breast cancer growth and metastasis 118 . Interestingly, Malat1 was linked to regulatory immune cells infiltrating tumour and to the regulation of cytotoxic T cells, NK cells and macrophages in the TME 119,120 . Suppression of Malat1 significantly enhanced Th1 and Th2 differentiation and lowered levels of IL‐10 immunosuppressive cytokine 120 .…”

RNA-mediated immunotherapy regulating tumor immune microenvironment: next wave of cancer therapeutics

“…In a preclinical study, it has been reported that attenuation of Neat1 can inhibit apoptosis and enhance antitumor cytolytic activity in CD8 + T cells [ 141 ]. Moreover, TIMER database analysis from Guo et al has indicated a major role of Malat1 in T cells development and function in patients with various cancer types [ 142 ]. Mouse models of breast cancer have shown high enrichment of LINK-A lncRNA expression in mammary gland tumors, and depletion of LINK-A expression repressed tumor progression [ 143 ].…”