Zircon U-Pb geochronology,Hf isotopes,and geochemistry constraints on the age and tectonic affinity of the basement granitoids from the Qiongdongnan Basin,northern South China Sea

Studies in the northern South China Sea(SCS)basement remain important for understanding the evolution of the Southeast Asian continental margin.Due to a thick cover of sediments and scarce borehole penetration,little is known about the age and tectonic affinity of this basement.In this study,an integrated study of zircon U-Pb geochronology,Hf isotopes,and whole-rock major and trace elements on seven basement granitoids from seven boreholes of Qiongdongnan Basin has been carried out.New zircon U-Pb results for these granitoids present middle-late Permian((270.0±1.2)Ma;(253±3.4)Ma),middle to late Triassic((246.2±3.4)Ma;(239.3±0.96)Ma;(237.9±0.99)Ma;(228.9±1.0)Ma)and Late Cretaceous ages((120.6±0.6)Ma).New data from this study,in combination with the previous dataset,indicates that granitoid ages in northern SCS basement vary from 270 Ma to 70.5 Ma,with three age groups of 270–196 Ma,162–142 Ma,and 137–71 Ma,respectively.Except for the late Paleozoic-Mesozoic rocks in the basement of the northern SCS,a few old zircon grains with the age of(2708.1±17)Ma to(2166.6±19)Ma provide clues to the existence of the pre-Proterozoic components.The geochemical signatures indicate that the middle Permian-early Cretaceous granitoids from the Qiongdongnan Basin are I-type granites formed in a volcanic arc environment,which were probably related to the subduction of the Paleo-Pacific Plate.

Combined local therapy and CAR-GPC3 T-cell therapy in advanced hepatocellular carcinoma:a proof-of-concept treatment strategy

Dear Editor,Available evidence regarding the most suitable treatment strategies for hepatocellular carcinoma(HCC)with inferior vena cava tumor thrombus(IVCTT)is extremely limited,and the median overall survival time for these patients after liver resection is only 17.76 months[1].Other local or systemic treatments for HCC with IVCTT result in a median overall survival time ranging from 5.88 to 15.36 months[1–3].Thus,new therapeutic strategies are urgently needed to improve the survival of HCC patients with IVCTT.Chimeric antigen receptor(CAR)T-cell therapy has seen success in treating B-cell neoplasms with impressive outcomes[4].However,this therapy alone has shown limited efficacy on solid tumors,such as HCC[5].

How mammalian piRNAs instruct de novo DNA methylation of transposons

A recent study published in Nature by Zoch et al.identifies a novel MIWI2-associated protein SPOCD1 and shows its requirement for piRNA-guided young transposable elements(TEs)methylation and silencing.1 This research provided the first mechanistic insights into how piRNA directs de novo DNA methylation in male mammals(Fig.1).