Alzheimer’s disease (AD) is a neurodegenerative disorder characterized by the accumulation of β-amyloid peptide 1-42 and phosphorylation of tau protein in the brain. Thus far, the transfer mechanism of these cytotoxic proteins between nerve cells remains unclear. Recent studies have shown that nanoscale extracellular vesicles (exosomes) originating from cells may play important roles in this transfer process. In addition, several genetic materials and proteins are also involved in intercellular communication by the secretion of the exosomes. That proposes novel avenues for early diagnosis and biological treatment in AD, based on exosome detection and intervention. In this review, exosome-related pathways of cytotoxic protein intercellular transfer in AD, and the effect of membrane proteins on exosomes targeting cells are first introduced. The advances in exosome-related biomarker detection in AD are summarized. Finally, the advantages and challenges of reducing cytotoxic protein accumulation via exosomal intervention for AD treatment are discussed. It is envisaged that future research in exosomes may well provide new insights into the pathogenesis, diagnosis, and treatment of AD.

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N6-methyladenosine (m6A) is the most prevalent internal modification of eukaryotic messenger RNAs (mRNAs). The m6A modification in RNA can be catalyzed by methyltransferases, or removed by demethylases, which are termed m6A writers and erasers, respectively. Selective recognition and binding by distinct m6A reader proteins lead mRNA to divergent destinies. m6A has been reported to influence almost every stage of mRNA metabolism and to regulate multiple biological processes. Accumulating evidence strongly supports the correlation between aberrant cellular m6A level and cancer. We summarize here that deregulation of m6A modification, resulting from aberrant expression or function of m6A writers, erasers, readers or some other protein factors, is associated with carcinogenesis and cancer progression. Understanding the regulation and functional mechanism of mRNA m6A modification in cancer development may help in developing novel and efficient strategies for the diagnosis, prognosis and treatment of human cancers.

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DIS3L2, in which mutations have been linked to Perlman syndrome, is an RNA-binding protein with 3′-5′ exoribonuclease activity. It contains two CSD domains and one S1 domain, all of which are RNA-binding domains, and one RNB domain that is responsible for the exoribonuclease activity. The 3′ polyuridine of RNA substrates can serve as a degradation signal for DIS3L2. Because DIS3L2 is predominantly localized in the cytoplasm, it can recognize, bind, and mediate the degradation of cytoplasmic uridylated RNA, including pre-microRNA, mature microRNA, mRNA, and some other non-coding RNAs. Therefore, DIS3L2 plays an important role in cytoplasmic RNA surveillance and decay. DIS3L2 is involved in multiple biological and physiological processes such as cell division, proliferation, differentiation, and apoptosis. Nonetheless, the function of DIS3L2, especially its association with cancer, remains largely unknown. We summarize here the RNA substrates degraded by DIS3L2 with its exonucleolytic activity, together with the corresponding biological functions it is implicated in. Furthermore, we discuss whether DIS3L2 can function independently of its 3′-5′ exoribonuclease activity, as well as its potential tumor-suppressive or oncogenic roles during cancer progression.