Background Colorectal cancer (CRC) is one of the most general malignant tumors. Accumulating evidence implied that long non-coding RNA Metastasis Associated Lung Adenocarcinoma Transcript 1 (MALAT1) participated in the tumorigenesis of CRC. However, the effect of MALAT1 in drug-resistance needed to be further illustrated. Methods Levels of MALAT1, microRNA (miR)-324-3p, and a disintegrin and metalloprotease metallopeptidase domain 17 (ADAM17) were detected using quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay. Cell Counting Kit 8 (CCK-8) was used to assess the half maximal inhibitory concentration (IC50) of oxaliplatin (Ox). Meanwhile, cell proliferation, migration and apoptosis were detected by CCK-8, transwell assay, and flow cytometry, respectively. The interaction between miR-324-3p and MALAT1 or ADAM17 was clarified by dual-luciferase reporter assay. Also, the effect of MALAT1 on tumor growth was detected in xenograft tumor mice treated with Ox. Results Significant up regulation of MALAT1 and ADAM17, and decrease of miR-324-3p were observed in Ox-resistant CRC tissues and cells. MALAT1 deficiency enhanced the sensitivity of Ox-resistant CRC cells response to Ox, while miR-324-3p repression or ADAM17 acceleration could overturn this effect. Moreover, MALAT1 silencing repressed tumor growth in Ox-treated nude mice. Mechanically, MALAT1 exerted promotion effect on the resistance response to Ox via miR-324-3p/ADAM17 axis in Ox-resistant CRC cells. Conclusion MALAT1 modulated the sensitivity of Ox through ADAM17 in Ox-resistant CRC cells by sponging miR-324-3p, thus MALAT1 might serve as a novel insight for the therapy of CRC.

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<p class="NewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNewNew">In this article, we report the cloning, characterization, and expression pattern of <em>Triticum aestivum DROOPING LEAF</em> gene (<em>TaDL</em>) in pistillody line of common wheat. Three <em>TaDL</em> homoeologous genes (<em>TaDL1</em>, <em>TaDL2</em>, and <em>TaDL3</em>) were isolated and found to be located on chromosomes 4AS, 4DL, and 4BL, respectively. The putative <em>TaDL1</em>, <em>TaDL2</em>, and <em>TaDL3</em> protein were 22.4, 22.6, and 22.3 kDa, with theoretical pI of 9.04, 9.04, and 8.98 and containing two distinct domains, namely, a zinc-finger domain in the N-terminal region and a C-terminal YABBY domain. The genome sequence of the three homologous genes consisted seven exons and six introns. All the introns, except for intron VI, varied in length and sequence composition. Phylogenetic analysis revealed that <em>TaDL</em> was most closely related to the <em>Brachypodium distachyon</em> <em>BdDL</em> and <em>Oryza sativa</em> <em>DL</em> genes. The expression pattern analysis indicated that <em>TaDL1</em>, <em>TaDL2</em>,<em> </em>and <em>TaDL3</em> have a higher expression levels in PS and P; however, the three genes are very rare in S. Thus, <em>TaDL</em> gene may contribute to pistil development. Moreover, overexpression of <em>TaDL</em> gene in stamens may cause complete or partial homeosis of stamens into pistils in wheat.</p>