RNF135 Promotes Human Osteosarcoma Cell Growth and Inhibits Apoptosis by Upregulating the PI3K/AKT Pathway.

BACKGROUND: Ring finger protein 135 (RNF135) is an E3 ubiquitin ligase that has been implicated in the tumorigenesis of multiple human malignancies. However, whether RNF135 plays a role in the development of human osteosarcoma (OS) remains unknown. METHODS: RNF135 expression in 20 human OS and 20 human osteochondroma specimens were evaluated by means of immunohistochemistry staining. The effects of shRNA-mediated RNF135 knockdown on human OS cell growth and apoptosis were evaluated through a panel of in vitro studies on cell proliferation, colony formation, exposure of phosphatidylserine on the cell surface, and caspase 3/7 activation. The protein levels of PI3K, AKT, and p-AKT were determined by western blot analysis. RESULTS: We detected significantly higher RNF135 levels in human OS tissues than human osteochondroma tissues. In in vitro studies, shRNA-mediated RNF135 knockdown in human OS cells inhibited proliferation and induced apoptosis. In addition, RNF135 knockdown reduced PI3K and p-AKT protein levels and activated caspase 3 and 7. CONCLUSIONS: These results supported that RNF135 contributes to human OS development through PI3K/AKT-dependent mechanisms. Targeting RNF135 may provide a new therapeutic approach for treating this human malignancy.

Concentration of polychlorinated biphenyls and risk assessment in finless porpoises from the East China Sea.

Polychlorinated biphenyls (PCBs) are bioaccumulative persistent organic pollutants with a great impact on cetaceans. To examine the content of PCBs and their risks to finless porpoises, this study determined the concentrations of seven typical PCB congeners in 56 tissue samples of East Asian finless porpoises (EAFPs) sampled in 2009-2012 from Ningbo (29.8835° N, 122.0644° E), Pingtan (25.5133° N, 119.8172° E) and Lvsi (32.1035° N, 121.6078° E). PCB138, PCB153 and PCB101 were the predominant congeners, accounting for 31.15%, 18.59% and 15.75%, respectively, of all PCBs detected. The content of PCBs increased with age in males but decreased from juveniles to adults in females due to transfer to calves by reproduction and lactation. EAFPs in Ningbo and Pingtan accumulated more PCBs than those in Lvsi Port. The trophic positions of EAFPs from Lvsi, Pingtan and Ningbo were 9.41, 8.95 and 9.43, respectively. PCB concentrations did not accumulate significantly with increasing trophic levels. The risk quotient index indicated that the risk of trichlorobiphenyl (3-PCB), tetrachlorobiphenyl (4-PCB), pentachlorobiphenyls (5-PCB), and hexachlorobiphenyls (6-PCB) to EAFPs in the East China Sea was generally low and within safe limits thus far. Supplementary Information: The online version contains supplementary material available at 10.1007/s43188-023-00221-0.

Spatiotemporal dynamics of the social structure of Indo-Pacific humpback dolphins ( Sousa chinensis) in Xiamen waters from 2007 to 2019.

As highly social animals, Indo-Pacific humpback dolphins ( Sousa chinensis) exhibit community differentiation. Nevertheless, our understanding of the external and internal factors influencing these dynamics, as well as their spatiotemporal variations, is still limited. In the present study, variations in the social structure of an endangered Indo-Pacific humpback dolphin population in Xiamen Bay, China, were monitored over two distinct periods (2007-2010 and 2017-2019) to analyze the effects of habitat utilization and the composition of individuals within the population. In both periods, the population demonstrated a strikingly similar pattern of social differentiation, characterized by the division of individuals into two main clusters and one small cluster. Spatially, the two primary clusters occupied the eastern and western waters, respectively, although the core distribution area of the eastern cluster shifted further eastward between the two periods. Despite this distribution shift, the temporal stability of the social structure and inter-associations within the eastern cluster remained unaffected. A subset of 16 individuals observed in both periods, comprising 51.6% and 43.2% of the population in each respective period, emerged as a foundational element of the social structure and may be responsible for sustaining social structure stability, especially during the 2007-2010 period. These observations suggest that the composition of dominant individuals, an internal factor, had a more substantial influence on the formation of the social network than changes in habitat use, an external factor. Consequently, the study proposes distinct conservation measures tailored to each of the two main clusters.