Activity of 2,6,9-trisubstituted purines as potent PDGFRα kinase inhibitors with antileukaemic activity

AGO2-RIP-Seq reveals miR-34/miR-449 cluster targetome in sinonasal cancers

Sinonasal tumours are heterogeneous malignancies, presenting different histological features and clinical behaviour. Many studies emphasize the role of specific miRNA in the development and progression of cancer, and their expression profiles could be used as prognostic biomarkers to predict the survival. Recently, using the next-generation sequencing (NGS)-based miRNome analysis the miR-34/miR-449 cluster was identified as miRNA superfamily involved in the pathogenesis of sinonasal cancers (SNCs). In the present study, we established an Argonaute-2 (AGO2): mRNA immunoprecipitation followed by high-throughput sequencing to analyse the regulatory role of miR-34/miR-449 in SNCs. Using this approach, we identified direct target genes (targetome), which were involved in regulation of RNA-DNA metabolic, transcript and epigenetic processes. In particular, the STK3, C9orf78 and STRN3 genes were the direct targets of both miR-34c and miR-449a, and their regulation are predictive of tumour progression. This study provides the first evidence that miR-34/miR-449 and their targets are deregulated in SNCs and could be proposed as valuable prognostic biomarkers.

3H-Pyrazolo[4,3-f]quinoline-Based Kinase Inhibitors Inhibit the Proliferation of Acute Myeloid Leukemia Cells In Vivo

The 3H-pyrazolo[4,3-f]quinoline moiety has been recently shown to be a privileged kinase inhibitor core with potent activities against acute myeloid leukemia (AML) cell lines in vitro. Herein, various 3H-pyrazolo[4,3-f]quinoline-containing compounds were rapidly assembled via the Doebner-Povarov multicomponent reaction from the readily available 5-aminoindazole, ketones, and heteroaromatic aldehydes in good yields. The most active compounds potently inhibit the recombinant FLT3 kinase and its mutant forms with nanomolar IC₅₀ values. Docking studies with the FLT3 kinase showed a type I binding mode, where the 3H-pyrazolo group interacts with Cys694 in the hinge region. The compounds blocked the proliferation of AML cell lines harboring oncogenic FLT3-ITD mutations with remarkable IC₅₀ values, which were comparable to the approved FLT3 inhibitor quizartinib. The compounds also inhibited the growth of leukemia in a mouse-disseminated AML model, and hence, the novel 3H-pyrazolo[4,3-f]quinoline-containing kinase inhibitors are potential lead compounds to develop into anticancer agents, especially for kinase-driven cancers.

Altered expression of striatin-4 is associated with poor prognosis in bladder transitional cell carcinoma

Striatin-4 (STRN4 or Zinedin) is a scaffolding protein belonging to the mammalian STRN family of proteins and consists of multiple functional signaling domains. Due to its numerous signaling complexes, STRN4 has been reported to be involved in the tumorigenesis of various cancer types, including colon cancer, liver cancer and prostate cancer. However, few studies on STRN4 have been conducted in bladder cancer, and its prognostic role in bladder cancer remains unknown. The present study aimed to investigate the expression levels of STRN4 in bladder transitional cell carcinoma and evaluate the prognostic role of STRN4. STRN4 expression in clinical specimens was analyzed using immunohistochemistry and reverse transcription-quantitative PCR. It was demonstrated that STRN4 expression was significantly associated with clinical parameters such as tumor size, muscle invasion depth and pathological tumor grade. Abnormal STRN4 expression was typically associated with worse overall survival time and outcome when compared with the low STRN4 expression group. Using multivariate analysis, it was reported that STRN4 was an independent prognostic biomarker for survival time in bladder transitional cell carcinoma. Although the specific biological mechanisms of STRN4 in bladder cancer still remain to be elucidated, STRN4 expression could be a prognostic indicator in bladder cancer.