New JAK3-INSL3 Fusion Transcript-An Oncogenic Event in Cutaneous T-Cell Lymphoma.

Constitutively activated tyrosine kinase JAK3 is implicated in the pathogenesis of cutaneous T-cell lymphomas (CTCL). The mechanisms of constitutive JAK3 activation are unknown although a JAK3 mutation was reported in a small portion of CTCL patients. In this study, we assessed the oncogenic roles of a newly identified JAK3-INSL3 fusion transcript in CTCL. Total RNA from malignant T-cells in 33 patients with Sézary syndrome (SS), a leukemic form of CTCL, was examined for the new JAK3-INSL3 fusion transcript by RT-PCR followed by Sanger sequencing. The expression levels were assessed by qPCR and correlated with patient survivals. Knockdown and/or knockout assays were conducted in two CTCL cell lines (MJ cells and HH cells) by RNA interference and/or CRISPR/Cas9 gene editing. SS patients expressed heterogeneous levels of a new JAK3-INSL3 fusion transcript. Patients with high-level expression of JAK3-INSL3 showed poorer 5-year survival (n = 19, 42.1%) than patients with low-level expression (n = 14, 78.6%). CTCL cells transduced with specific shRNAs or sgRNAs had decreased new JAK3-INSL3 fusion transcript expression, reduced cell proliferation, and decreased colony formation. In NSG xenograft mice, smaller tumor sizes were observed in MJ cells transduced with specific shRNAs than cells transduced with controls. Our results suggest that the newly identified JAK3-INSL3 fusion transcript confers an oncogenic event in CTCL.

Alpinoid c analog inhibits angiogenesis and induces apoptosis in COLO205 cell line.

Diarylheptanoids display an array of biological and pharmacological properties. We previously reported the synthesis of a diarylheptanoid Alpinoid c and a series of its derivatives, evaluated their cytotoxicity against various human cancer cells. We found some of these derivatives were significantly more potent than Alpinoid c in preventing the proliferation of various cancer cell lines. Among these, (S, E)-1-(3, 4 dimethoxyphenyl)-6-hydroxy-7-phenylhept-4-en-3-one (DPHP) showed most potent cytotoxicity against COLO205 cells, however, the mechanism by which DPHP prevents the growth of these colon cancer cells remains unknown. In the current study, we investigated the molecular mechanism of DPHP on colon cancer cells. DPHP inhibited the proliferation of COLO205 (IC50 7.01 ±â€¯0.62 µM) and A549 (IC50 20.03 ±â€¯3.11 µM) cells more specifically than normal human colon epithelial cell line NCM460 (IC50 55.6 ±â€¯4.02 µM). In COLO205 cells, DPHP induced cell shrinkage, membrane blebbing, chromatin condensation, phosphatidylserine externalization, and an accumulation of cells at sub-G1 phase. Further analysis these cells treated with DPHP revealed a decrease in mitochondrial membrane potential, an increase in Bax/Bcl2 ratio, the release of cytochrome c, activation of caspases -9, -3/7, and cleavage of the poly-ADP-ribose polymerase. DPHP treatment resulted in inhibition of hypoxia induced VEGF downstream signaling pathway in COLO205 cells is concurrent with inhibition of angiogenesis in CAM. Based on these data we suggest that DPHP significantly induced apoptosis possibly via intrinsic mitochondrial apoptosis pathway and inhibited angiogenesis. Our study suggests DPHP could be a therapeutic agent in treating colon cancer.

Hematopoietic PBX-interacting protein is a substrate and an inhibitor of the APC/C-Cdc20 complex and regulates mitosis by stabilizing cyclin B1.

Proper cell division relies on the coordinated regulation between a structural component, the mitotic spindle, and a regulatory component, anaphase-promoting complex/cyclosome (APC/C). Hematopoietic PBX-interacting protein (HPIP) is a microtubule-associated protein that plays a pivotal role in cell proliferation, cell migration, and tumor metastasis. Here, using HEK293T and HeLa cells, along with immunoprecipitation and immunoblotting, live-cell imaging, and protein-stability assays, we report that HPIP expression oscillates throughout the cell cycle and that its depletion delays cell division. We noted that by utilizing its D box and IR domain, HPIP plays a dual role both as a substrate and inhibitor, respectively, of the APC/C complex. We observed that HPIP enhances the G2/M transition of the cell cycle by transiently stabilizing cyclin B1 by preventing APC/C-Cdc20-mediated degradation, thereby ensuring timely mitotic entry. We also uncovered that HPIP associates with the mitotic spindle and that its depletion leads to the formation of multiple mitotic spindles and chromosomal abnormalities, results in defects in cytokinesis, and delays mitotic exit. Our findings uncover HPIP as both a substrate and an inhibitor of APC/C-Cdc20 that maintains the temporal stability of cyclin B1 during the G2/M transition and thereby controls mitosis and cell division.

Synthesis of Novel Diaziridinyl Quinone Isoxazole Hybrids and Evaluation of Their Anti-Cancer Activity as Potential Tubulin-Targeting Agents.

Two series of diaziridinyl quinone isoxazole derivatives were prepared and evaluated for their cytotoxic activity against MCF7, HeLa, BT549, A549 and HEK293 cell lines and interaction with tubulin. Compounds (6A-M: ) showed promising activity against all the 5 human cancer cell lines. Compounds 6A: , 6E: and 6 M: were potent [IC50 ranging between 2.21 µg to 2.87 µg] on ER-positive MCF7 cell line similar to the commercially available drug molecule Doxorubicin. The results from docking models are in consistent with the experimental values which demonstrated the favourable binding modes of compounds 6A-M: to the interface of α- and ß-tubulin dimer.

Synthesis and biological evaluation of novel quinazoline-sulfonamides as anti-cancer agents.

A robust economic approach to N-(quinazoline-4-yl)sulfonamides was developed and synthesized different aryl, hetero aryl, alkyl and cyclopropyl sulfonamides in excellent yields. All the compounds were evaluated for cytotoxic affinity to SKOV3, DU145, THP1, U937, and COLO205 cell lines. Interesting to find that the bulkiness of substituent at C-2 position of quinazoline forces the molecule to flip around in order to bind in the active site, when compared to the binding preference of previously known quinazoline compounds. Among the 21 compounds synthesized 2b, 2d, 2e, 2h, 2i, 3c, 3d, 3f, 3g and 3h found to be active on all the cell lines tested with IC50 values <10µg/mL. Performed docking simulations to understand the binding preference of various C-2 substituted quinazoline sulfonamides.

Spatane diterpinoid from the brown algae, Stoechospermum marginatum induces apoptosis via ROS induced mitochondrial mediated caspase dependent pathway in murine B16F10 melanoma cells.

Spatane diterpinoids isolated from the brown marine algae Stoechospermum marginatum were known to have cytotoxic effects in human cancerous cell lines and murine melanoma cells; the underling apoptotic mechanism of diterpinoids still remains unclear so far. Thus, in the present study, the apoptotic mechanism of a spatane diterpinoid, 5(R), 19-diacetoxy-15,18(R and S), dihydro spata-13, 16(E)-diene (DDSD) was investigated mainly in B16F10 melanoma cells because they were most susceptible to DDSD than THP1, U937, COLO205, and HL60 cells. The treatment of B6F10 cells with DDSD resulted in morphological alterations, nuclear condensation, and DNA fragmentation, which leads to cell growth inhibition in a concentration-dependent manner. Data indicate that DDSD induced the generation of ROS, consequentially caused alteration in Bax/Bcl-2 ratio that disrupted the inner mitochondrial transmembrane potential (ΔΨm) resulting in cytochrome c redistribution to the cytoplasm and activation of caspase-mediated apoptotic pathway. Flow cytometric analysis clearly indicated that the DDSD inducing phosphatidylserine externalization and mediated "S-phase" arrest in cell cycle. In addition, results also found that DDSD induced apoptosis through deregulating PI3K/AKT signaling pathway. The anti-tumor activity of DDSD was evaluated in C57BL/6 mice bearing B16F10 melanoma. It effectively inhibited tumor growth (volume and weight) in a dose dependent manner, yet without apparent toxic effects. Morphology and apoptotic status of tumor tissues in the treated mice were assessed by microscopy and TUNEL assay, respectively. Our study shows a therapeutic potential of DDSD for the treatment of malignant melanoma and a new source of anticancer drugs. © 2016 Wiley Periodicals, Inc.