It has been speculated that before vertebrates evolved somatic diversity-based adaptive immunity, the germline-encoded diversity of innate immunity may have been more developed. Amphioxus occupies the basal position of the chordate phylum and hence is an important reference to the evolution of vertebrate immunity. Here we report the first comprehensive genomic survey of the immune gene repertoire of the amphioxus Branchiostoma floridae. It has been reported that the purple sea urchin has a vastly expanded innate receptor repertoire not previously seen in other species, which includes 222 toll-like receptors (TLRs), 203 NOD/NALP-like receptors (NLRs), and 218 scavenger receptors (SRs). We discovered that the amphioxus genome contains comparable expansion with 71 TLR gene models, 118 NLR models, and 270 SR models. Amphioxus also expands other receptor-like families, including 1215 C-type lectin models, 240 LRR and IGcam-containing models, 1363 other LRR-containing models, 75 C1q-like models, 98 ficolin-like models, and hundreds of models containing complement-related domains. The expansion is not restricted to receptors but is likely to extend to intermediate signal transducers because there are 58 TIR adapter-like models, 36 TRAF models, 44 initiator caspase models, and 541 death-fold domain-containing models in the genome. Amphioxus also has a sophisticated TNF system and a complicated complement system not previously seen in other invertebrates. Besides the increase of gene number, domain combinations of immune proteins are also increased. Altogether, this survey suggests that the amphioxus, a species without vertebrate-type adaptive immunity, holds extraordinary innate complexity and diversity.

Recurrence and metastasis result in a poor prognosis for breast cancer patients. Recent studies have demonstrated that microRNAs (miRNAs) play vital roles in the development and metastasis of breast cancer. In this study, we investigated the therapeutic potential of miR-34a in breast cancer. We found that miR-34a is downregulated in breast cancer cell lines and tissues, compared with normal cell lines and the adjacent nontumor tissues, respectively. To explore the therapeutic potential of miR-34a, we designed a targeted miR-34a expression plasmid (T-VISA-miR-34a) using the T-VISA system, and evaluated its antitumor effects, efficacy, mechanism of action, and systemic toxicity. T-VISA-miR-34a induced robust, persistent expression of miR-34a, and dramatically suppressed breast cancer cell growth, migration, and invasion in vitro by downregulating the protein expression levels of the miR-34a target genes E2F3, CD44, and SIRT1. In an orthotopic mouse model of breast cancer, intravenous injection of T-VISA-miR-34a:liposomal complex nanoparticles significantly inhibited tumor growth, prolonged survival, and did not induce systemic toxicity. In conclusion, T-VISA-miR-34a lead to robust, specific overexpression of miR-34a in breast cancer cells and induced potent antitumor effects in vitro and in vivo. T-VISA-miR-34a may provide a potentially useful, specific, and safe-targeted therapeutic approach for breast cancer.

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Long non-coding RNAs (lncRNAs) have been tested to act as important regulator in liver cancer genesis and progression. LncRNA Nicotinamide Nucleotide Transhydrogenase-antisense RNA1 (NNT-AS1) has been reported to participate in the tumorigenesis. However, the exact molecular mechanism of NNT-AS1 in hepatocellular carcinoma (HCC) is still unknown. In present study, our team identified the up-regulated expression of NNT-AS1 in HCC tissue and cell lines compared with adjacent noncancerous tissue and normal cells. Moreover, HCC patients with high NNT-AS1 levels had poor prognosis than that with low NNT-AS1 level (p=0.0089). In vitro, gain- and loss-of-function experiments revealed that enhanced NNT-AS1 expression promoted the proliferation ability and alleviated the cycle arrest and apoptosis, while NNT-AS1 knockdown suppressed the proliferation and induced G0/G1 phase arrest and apoptosis. In vivo, NNT-AS1 knockdown inhibited the HCC neoplastic tumor volume and weight. Bioinformatics analysis and luciferase reporter assay validated that miR-363 targeted NNT-AS1 and CDK6 3’-UTR. MiR-363 was down-regulated in HCC tissue and cells. NNT-AS1 competed with CDK6 for miR-363 binding and could increase CDK6 expression. In summary, our results suggest the oncogenic role of NNT-AS1 in HCC tumorigenesis through miR-363/CDK6 axis, providing a novel therapeutic target for human HCC.

Among five Toll/IL-1R resistance adaptors, sterile α and Toll/IL-1R resistance motif containing protein (SARM) is the only one conserved from Caenorhabditis elegans to human. However, its physiologic roles are hardly understood, and its involvement in TLR signaling remains debatable. In this study, we first demonstrated a predominant expression of amphioxus SARM (Branchiostoma belcheri tsingtauense SARM) in neural cells during embryogenesis and its predominant expression in the digestive system from larva to adult, suggesting its primitive role in neural development and a potential physiologic role in immunity. We further found that B. belcheri tsingtauense SARM was localized in mitochondria and could attenuate the TLR signaling via interacting with amphioxus MyD88 and tumor necrosis receptor associated factor 6. Thus, amphioxus SARM appears unique in that it may play dual functions in neural development and innate immunity by targeting amphioxus TLR signaling.