A flavonoid glycoside, quercitrin (1), and two phenylpropanoyl sucrose derivatives, vanicoside B (2) and lapathoside C (3), were isolated for the first time from the herb Persicaria dissitif lora. Vanicoside B (2) exhibited antiproliferative activity against a panel of cancer cell lines in triple-negative breast cancer (TNBC) MDA-MB-231 cells. The underlying mechanisms of the antitumor activity of 2 were investigated in TNBC cells. Upregulation of cyclindependent kinase 8 (CDK8) was observed in a claudin-low molecular subtype of TNBC cells. A molecular modeling study indicated that 2 showed a high affinity for CDK8. Further investigations revealed that 2 suppressed CDK8-mediated signaling pathways and the expression of epithelial−mesenchymal transition proteins and induced cell cycle arrest and apoptosis in MDA-MB-231 and HCC38 TNBC cells. Moreover, 2 inhibited tumor growth without overt toxicity in a nude mouse xenograft model implanted with MDA-MB-231 cells. Taken together, these findings demonstrate the significance of CDK8 activity in TNBC and suggest a potential use of 2 as a therapeutic candidate for the treatment of aggressive human triple-negative breast cancer.

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Background/Aim: The resistance to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib or erlotinib, is considered a major challenge in the treatment of patients with non-small cell lung cancer (NSCLC). Herein, we identified the critical roles of anterior gradient 2 (AGR2) in gefitinib (Gef) resistance of mutant NSCLC cells. Materials and Methods: Using datasets from a pair of NSCLCsensitive and NSCLC-resistant cells, immunoblotting, immunofluorescence and immunohistochemistry, and cell viability assays were applied to identify the effects of AGR2. Results: AGR2 was found to be significantly over-expressed in Gef-resistant cells and was highly associated with drug resistance, proliferation, migration, and invasion of cancer cells. Moreover, AGR2 and ADAMTS6 formed a negative feedback loop in drug-resistant cells. Conclusion: Modulation of overexpression of AGR2 in mutant NSCLC cells may be an attractive therapeutic strategy for the treatment of EGFR-TKI-resistant NSCLC. Non-small cell lung cancer (NSCLC) is one of the major causes of cancer-related death worldwide, and comprises 85% of all lung cancer cases (1). Acquired drug resistance in tumor cells is a major obstacle in the field of anti-cancer chemotherapies. Likewise, NSCLC patients who initially show a good response to epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs), such as gefitinib (Gef), acquire resistance to treatment (2). However, studies on the mechanisms through which overexpression of specific genes is involved in EGFR-TKI resistanse of NSCLC cells are scarce and its role remains to be elucidated. Therefore, novel approaches are required to elucidate their role in drug resistanse of cancer cells. The anterior gradient-2 (AGR2) has been identified in Xenopus laevis and plays a critical role in cemet gland differentiation (3). Recent studies have suggested that elevated expression of AGR2 is correlated with cell proliferation, metastasis, and drug resistance in various human cancer cell lines, such as prostate (4), breast (5), and pancreatic cancer (6). Moreover, overexpression of AGR2 has been notably correlated with a poor outcome of estrogen receptor-negative breast cancer patients (7). AGR2 is also a pro-oncogenic protein that has been shown to stimulate the epidermal growth factor receptor (EGFR) ligand amphiregulin, regulate p53 signaling, and interact with the AAA+ protein Reptin (8), suggesting its modulatory roles in gene expression. High expression of AGR2 has also been shown to be predictive of poor survival in lung cancer (9). However, there is still a lack of insightful understanding of the role of AGR2 in EGFR-TKI-resistant NSCLC cells. There are 19 members of zinc-dependent metalloproteases in the family of a disintegrin and metalloprotease with thrombospondin motifs (ADAMTS) (10). Recent reports suggest the critical roles of ADAMTSs in angiogenesis and cancer (11). They also play an important role in the modulation of extracellular matrix. For instance, ADAMTS-1 metallopro...

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A potential therapeutic target to curb obesity and diabetes is thermogenic beige adipocytes. However, beige adipocytes quickly transition into white adipocytes upon removing stimuli. Here, we define the critical role of cyclin dependent kinase inhibitor 2A (Cdkn2a) as a molecular pedal for the beige-to-white transition. Beige adipocytes lacking Cdkn2a exhibit prolonged lifespan, and male mice confer long-term metabolic protection from diet-induced obesity, along with enhanced energy expenditure and improved glucose tolerance. Mechanistically, Cdkn2a promotes the expression and activity of beclin 1 (BECN1) by directly binding to its mRNA and its negative regulator BCL2 like 1 (BCL2L1), activating autophagy and accelerating the beige-to-white transition. Reactivating autophagy by pharmacological or genetic methods abolishes beige adipocyte maintenance induced by Cdkn2a ablation. Furthermore, hyperactive BECN1 alone accelerates the beige-to-white transition in mice and human. Notably, both Cdkn2a and Becn1 exhibit striking positive correlations with adiposity. Hence, blocking Cdkn2a-mediated BECN1 activity holds therapeutic potential to sustain beige adipocytes in treating obesity and related metabolic diseases.