Alternative splicing is increasingly associated with cancers. HnRNP L is a splicing factor that promotes carcinogenesis in head and neck squamous cell carcinoma (HNSCC) and other cancers. Alternative exon 7 of hnRNP L contains an in-frame stop codon. Exon 7-included transcripts can be degraded via nonsense-mediated decay or encode a truncated hnRNP L protein. Exon 7-excluded transcripts can encode full-length functional hnRNP L protein. HnRNP L has an autoregulation mechanism by promoting the inclusion of its own exon 7. This study aimed to understand the relationship between the alternative splicing of exon 7 and HNSCC. Oncogenic splicing factor SRSF3 has an alternative exon 4 and similar autoregulation mechanism. HnRNP L promotes SRSF3 exon 4 inclusion and then inhibits SRSF3 autoregulation.The relationship between alternative splicing of hnRNP L exon 7 and clinical characteristics of HNSCC in a TCGA dataset was analyzed and confirmed by RT-PCR in a cohort of 61 oral squamous cell carcinoma (OSCC) patients. The regulators of exon 7 splicing were screened in 29 splicing factors and confirmed by overexpression or silencing assay in HEK 293, CAL 27, and SCC-9 cell lines.The inclusion of hnRNP L exon 7 was significantly negatively associated with the progression and prognosis of HNSCC, which was confirmed in the cohort of 61 OSCC patients. SRSF3 inhibited exon 7 inclusion and hnRNP L autoregulation and then promoted the expression of full-length functional hnRNP L protein. SRSF3 exon 4 inclusion was correlated with hnRNP L exon 7 inclusion in both HNSCC and breast cancer. HNSCC patients with both low hnRNP L exon 7 and SRSF3 exon 4 inclusion show poor overall survival.Inclusion of hnRNP L alternative exon 7 is associated with good prognosis and inhibited by oncogene SRSF3 in HNSCC.
Nano-agent-mediated photothermal therapy (PTT) combined with chemotherapy has been proposed as an effective strategy against cancer. However, chemotherapeutic agents often cause serious side effects. Herein, a novel PTT nanoagent (Cy5.5-MSA-G250) with unanticipated intrinsic tumor-selective cytotoxicity is developed. The Cy5.5-MSA-G250 nanoparticles (NPs) are created by mixing mouse serum albumin (MSA) and coomassie brilliant blue (G250) and then conjugated with cyanine 5.5 (Cy5.5). As expected, Cy5.5-MSA-G250 NPs can efficiently kill cancer cells in vitro and in vivo by PTT. Meanwhile, we accidentally discover that Cy5.5-MSA-G250 have intrinsic specific cytotoxicity against tumor cells but not against normal cells. Moreover, the tumor-specific cytotoxicity of Cy5.5-MSA-G250 is much stronger than that of cytarabine, an FDA-approved anticancer drug. In vivo experiments also prove that Cy5.5-MSA-G250 NPs can effectively eliminate residual tumor cells and prevent metastasis. Further study indicates that selective induction of G1 cell cycle arrest and inhibition of DNA duplication in tumor cells may be the possible mechanism of the tumor cell-selective cytotoxicity of Cy5.5-MSA-G250 NPs. In addition, direct visualization, low systematic toxicity, good biodegradation, and efficient body excretion further make Cy5.5-MSA-G250 NPs attractive for in vivo applications. Taken together, Cy5.5-MSA-G250 NPs are proven to be a promising platform for combined photothermal chemotherapy.
Differentiated thyroid carcinoma (DTC) is one of the most common malignant tumors. Increasing evidence indicates that centromere protein K(CENPK) may play a key role in promoting carcinogenesis. The expression, biological functions, and clinical significance of CENPK in DTC are still unclear. The CENPK expression in the DTC specimen was confirmed using quantitative real-time PCR and Western blot. The expression of CENPK was silenced and promoted by lentivirus-mediated transfection with shRNA sequences or CENPK plasmid targeting CENPK in TPC1 and FTC-133 cells, respectively. Colony formation, Cell Counting Kit-8 (CCK-8), Transwell invasion, and scratch assays were performed to assess the malignant biological properties of FTC-133 and TPC1 cells. Tumorigenicity assay was performed using C57BL/6 mice to explore the influence of CENPK on the growth of TPC1. The present work suggested that the expression of CENPK remarkably increased in follicular thyroid cancer and papillary thyroid cancer tissue samples at the mRNA level. Immunohistochemical staining also showed consistent results at the protein level. In addition, CENPK mRNA expression level showed great value in diagnosis of DTC. Knockdown of CENPK significantly inhibited the invasion and migration of TPC1 and FTC-133 cells. In contrast, CENPK overexpression promoted invasion and migration of TPC1 and FTC-133 cells. Knockdown and overexpression of CENPK showed consistent effect on DTC tumor growth and expression of Ki-67 invivo. Our results indicated that CENPK was evidently upregulated in DTC. Knocking down CENPK suppressed TPC1 cell proliferation, invasion and migration. Targeting the CENPK may be anovel therapeutic method for DTC.
Abstract 1D flexible fibers assembled 3D porous networked ceramic fiber aerogels (CFAs) are developed to overcome the brittleness of traditional ceramic particle aerogels. However, existing CFAs with disordered and quasi‐ordered structures fail to balance the relationship between flexibility, robustness, and thermal insulation. Creating novel architectural CFAs with an excellent combination of performances has proven extremely challenging. In this paper, a novel strategy is adopted to fabricate porous mullite fibrous aerogels (MFAs) with ordered structures by combining fiber sedimentation and electric field‐induced fiber alignment techniques. For the first time, electric field‐induced alignment of ceramic fibers is utilized to prepare bulk aerogels on a large scale. The resulting MFAs exhibit ultra‐low high‐temperature thermal conductivity of 0.0830 W m −1 K −1 at 1000 °C, anisotropic mechanical and sound absorption performances, and multifunctionality in terms of the combination of thermal insulation, sound absorption, and hydrophobicity. The successful synthesis of such fascinating materials may provide new insights into the design and development of multifunctional CFAs for various applications.