Tea is one of the most popular beverages consumed worldwide. The relationship between tea consumption and human cancer incidence is an important concern. This topic has been studied in different populations by many investigators, but no clear-cut conclusion can be drawn. Whereas some studies have shown a protective effect of tea consumption against certain types of cancers, other studies have indicated an opposite effect. Our purpose is to provide a critical review of this topic, covering basic chemistry and biochemical activity of tea, epidemiologic investigations, and laboratory studies, as well as possible directions for future research. Studies have demonstrated either a lack of association between tea consumption and cancer incidence at specific organ sites or inconsistent results. On the other hand, many laboratory studies have demonstrated inhibitory effects of tea preparations and tea polyphenols against tumor formation and growth. This inhibitory activity is believed to be mainly due to the antioxidative and possible antiproliferative effects of polyphenolic compounds in green and black tea. These polyphenolics may also inhibit carcinogenesis by blocking the endogenous formation of N-nitroso compounds, suppressing the activation of carcinogens, and trapping of genotoxic agents. The effect of tea consumption on cancer is likely to depend on the causative factors of the specific cancer. Therefore, a protective effect observed on a certain cancer with a specific population may not be observable with a cancer of a different etiology. On the basis of this concept, we suggest future laboratory and epidemiologic studies to elucidate the relationship between tea consumption and human cancer risk.

Prostate tumours are highly variable in their response to therapies, but clinically available prognostic factors can explain only a fraction of this heterogeneity. Here we analysed 200 whole-genome sequences and 277 additional whole-exome sequences from localized, non-indolent prostate tumours with similar clinical risk profiles, and carried out RNA and methylation analyses in a subset. These tumours had a paucity of clinically actionable single nucleotide variants, unlike those seen in metastatic disease. Rather, a significant proportion of tumours harboured recurrent non-coding aberrations, large-scale genomic rearrangements, and alterations in which an inversion repressed transcription within its boundaries. Local hypermutation events were frequent, and correlated with specific genomic profiles. Numerous molecular aberrations were prognostic for disease recurrence, including several DNA methylation events, and a signature comprised of these aberrations outperformed well-described prognostic biomarkers. We suggest that intensified treatment of genomically aggressive localized prostate cancer may improve cure rates.

A facile and scalable in situ chemical vapor deposition (CVD) technique using metal precursors as a catalyst and a three-dimensional (3D) self-assembly of NaCl particles as a template is developed for one-step fabrication of 3D porous graphene networks anchored with Sn nanoparticles (5-30 nm) encapsulated with graphene shells of about 1 nm (Sn@G-PGNWs) as a superior lithium ion battery anode. In the constructed architecture, the CVD-synthesized graphene shells with excellent elasticity can effectively not only avoid the direct exposure of encapsulated Sn to the electrolyte and preserve the structural and interfacial stabilization of Sn nanoparticles but also suppress the aggregation of Sn nanoparticles and buffer the volume expansion, while the interconnected 3D porous graphene networks with high electrical conductivity, large surface area, and high mechanical flexibility tightly pin the core-shell structure of Sn@G and thus lead to remarkably enhanced electrical conductivity and structural integrity of the overall electrode. As a consequence, this 3D hybrid anode exhibits very high rate performance (1022 mAh/g at 0.2 C, 865 mAh/g at 0.5 C, 780 mAh/g at 1 C, 652 mAh/g at 2 C, 459 mAh/g at 5 C, and 270 mAh/g at 10 C, 1 C = 1 A/g) and extremely long cycling stability even at high rates (a high capacity of 682 mAh/g is achieved at 2 A/g and is maintained approximately 96.3% after 1000 cycles). As far as we know, this is the best rate capacity and longest cycle life ever reported for a Sn-based lithium ion battery anode.

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