Inhibition of G9a by a small molecule inhibitor, UNC0642, induces apoptosis of human bladder cancer cells.

Urinary bladder cancer (UBC) is characterized by frequent recurrence and metastasis despite the standard chemotherapy with gemcitabine and cisplatin combination. Histone modifiers are often dysregulated in cancer development, thus they can serve as an excellent drug targets for cancer therapy. Here, we investigated whether G9a, one of the histone H3 methyltransferases, was associated with UBC development. We first analyzed clinical data from public databases and found that G9a was significantly overexpressed in UBC patients. The TCGA Provisional dataset showed that the average expression level of G9a in primary UBC samples (n = 408) was 1.6-fold as much as that in normal bladder samples (n = 19; P < 0.001). Then we used small interfering RNA to knockdown G9a in human UBC T24 and J82 cell lines in vitro, and observed that the cell viability was significantly decreased and cell apoptosis induced. Next, we choosed UNC0642, a small molecule inhibitor targeting G9a, with low cytotoxicity, and excellent in vivo pharmacokinetic properties, to test its anticancer effects against UBC cells in vitro and in vivo. Treatment with UNC0642 dose-dependently decreased the viability of T24, J82, and 5637 cells with the IC50 values of 9.85 ± 0.41, 13.15 ± 1.72, and 9.57 ± 0.37 µM, respectively. Furthermore, treatment with UNC0642 (1-20 µM) dose-dependently decreased the levels of histone H3K9me2, the downstream target of G9a, and increased apoptosis in T24 and J82 cells. In nude mice bearing J82 engrafts, administration of UNC0642 (5 mg/kg, every other day, i.p., for 6 times) exerted significant suppressive effect on tumor growth without loss of mouse body weight. Moreover, administration of UNC0642 significantly reduced Ki67 expression and increased the level of cleaved Caspase 3 and BIM protein in J82 xenografts evidenced by immunohistochemistry and western blot analysis, respectively. Taken together, our data demonstrated that G9a may be a promising therapeutic target for UBC, and an epigenetics-based therapy by UNC0642 is suggested.

Design, synthesis and biological evaluation of novel benzo-α-pyrone containing piperazine derivatives as potential BRAFV600E inhibitors.

The increasingly acquired resistance to vemurafenib and side effects of known inhibitors motivate the search for new and more effective anti-melanoma drugs. In this Letter, virtual screening and scaffold growth were combined together to achieve new molecules as BRAFV600E inhibitors. Along with docking simulation, a primary screen in vitro was performed to filter the modifications for the lead compound, which was then substituted, synthesized and evaluated for their inhibitory activity against BRAFV600E and several melanoma cell lines. Out of the obtained compounds, derivative 3l was identified as a potent BRAFV600E inhibitor and exerted an anticancer effect through BRAFV600E inhibition. The following biological evaluation assays confirmed that 3l could induce cell apoptosis and marked DNA fragmentation. Furthermore, 3l could arrest the cell cycle at the G0/G1 phase in melanoma cells. The docking simulation displayed that 3l could tightly bind with the crystal structure of BRAFV600E at the active site. Overall, the biological profile of 3l suggests that this compound may be developed as a potential anticancer agent.

Discovery of Chromeno[4,3-c]pyrazol-4(2H)-one Containing Carbonyl or Oxime Derivatives as Potential, Selective Inhibitors PI3Kα.

A series of novel chromeno[4,3-c]pyrazol-4(2H)-one containing carbonyl or oxime derivatives (4a-n, 5a-n) have been synthesized and evaluated their biological activities as phosphatidyl inositol 3-kinase (PI3K) inhibitors. Out of them, compound 5l showed the most potent antiproliferative activities against HCT-116 with IC50 of 0.10 µM in vitro, and exhibited the most potent activity for PI3Kα with the value of 0.012 µM. Docking simulation of 5l into PI3Kα active site were performed to determine the probable binding model, and it indicated that compound 5l could be optimized as a potential inhibitor of PI3Kα in the further study.

Clinicopathological, immunohistochemical, and ultrastructural study of 13 cases of melanotic schwannoma.

BACKGROUND: Melanotic schwannoma is a rare variant of schwannoma composed of melanin-producing cells with ultrastructural features of schwann cells. The description of the course of the tumors differs somewhat, but it is generally considered as a benign lesion. We investigated the clinicopathologic features, immunophenotypes, and ultrastructural features of 13 patients with nonpsammomatous melanotic schwannoma (NPMS). METHODS: Tumor specimens of each patient were sectioned and stained with hematoxylin-eosin, Fontana-Masson, Prussian blue, and periodic acid-Schiff (PAS). Immunohistochemical markers such as S-100, Leu-7, HMB-45, Melan-A, CK, EMA, vimentin, GFAP, laminin, collagen IV and MIB-1 were detected with the Envision immunohistochemical staining method. Four of the cases were observed by electron microscopy. RESULTS: Of the 13 patients, 8 were male and 5 female, aged from 11 to 92 years (mean, 38.6 years). The tumor sites included the spinal nerve root (5 patients), cranial nerve (1), greater omentum (1), subcutaneous tissue (3), mesentery (1), bone (1) and mediastinum (1). Eleven patients were followed up for over 2 years, with a mean of 5.9 years. One patient (9.1%) with a primary tumor in the greater omentum developed another primary tumor of the same type in the subcutaneous tissue of the abdominal wall after the first operation. Local recurrence of the tumor was seen in 2 patients (18.2%). One patient (9.1%) showed the local recurrence and metastasis. Seven patients (63.6%) showed no evidence of the recurrence or metastasis. Grossly, all tumors were well-circumscribed and the gross findings were suggestive of melanin-containing tumors. The tumor was composed of spindled and epithelioid cells with abundant intracytoplasmic melanin pigments. Nuclei were round and contained delicate, evenly distributed chromatins as well as small, distinct nucleoli. In some areas, the nucleoli were large and prominent. Rare mitoses were seen in most lesions except the larger omentum lesion. The pigment was shown to be positive for the Fontana-Masson and negative for Prussian blue and PAS. Immunohistochemical staining for S-100, Leu-7, HMB-45, Melan-A, and vimentin were strongly positive. Linear immunoreactions of both laminin and collagen IV was detected in all patients. Ultrastructurally, numerous elongated tumor-cell processes, duplicated basement membrane and melanosomes were observed in all developmental stages. CONCLUSIONS: Histologically, melanotic schwannoma is a rare variant of schwannoma composed of melanin-producing cells with ultrastructural features of schwann cells. Distinguishing between this tumor and malignant melanoma is of paramount importance in planning of management. Immunohistochemically, combined use of laminin and collagen IV is valuable in distinguishing melanotic schwannoma from malignant melanoma. Wide local resection and additional radiotherapy should be advocated. Further studies including cytogenetic or molecular biology are still required to better delineate melanotic schwannoma from malignant melanoma. Appropriate long-term follow-up is needed for all melanotic schwannomas.

[Diagnostic value of A103 and inhibin-alpha in adrenocortical tumors: an immunohistochemical study using tissue microarray techniques].

OBJECTIVE: To investigate the potential diagnostic value of A103 and inhibin-alpha in adrenocortical tumors and to evaluate the applicability of tissue microarray/tissue chip in pathological studies using immunohistochemistry. METHODS: A tissue microarray/tissue chip was constructed to contain 179 formalin-fixed, paraffin-embedded adrenal tissue samples which include 3 normal adrenal cortex, 2 fetal adrenal cortex, 2 nodular adrenocortical hyperplasia samples, 72 adrenocortical adenomas, 39 adrenocortical carcinomas, 3 adrenal medulla, 13 metastatic carcinomas, 4 metastatic malignant melanomas and 44 pheochromocytomas. Additional 20 cases of normal adult adrenal gland were used as controls. Immunohistochemical markers, including A103, inhibin-alpha, calretinin and Ki-67 were used on the tissue array sections by EnVision immunohistochemical staining methods. RESULTS: Positive staining of A103 was seen in all of the 23 (100%) adrenal cortex, 2 fetal adrenal cortex, 2 nodular adrenocortical hyperplasia samples, 60 of 66 (90.9%) adrenocortical adenomas samples, 35 of 37 (94.6%) adrenocortical carcinomas samples, 3 of 3 malignant melanomas, but in none of the adrenal medulla, pheochromocytomas or adrenal metastatic carcinoma samples. In all of the adrenal cortex, fetal adrenal cortex and nodular adrenocortical hyperplasia cases, inhibin-alpha immunoreactivity was limited to the zona reticularis and the innermost zona fasciculata. Fifty of the 66 (75.8%) adrenocortical adenomas, 28 of the 37 (75.7%) adrenocortical carcinomas were positive for inhibin-alpha. None of the adrenal medulla, pheochromocytoma, metastatic malignant melanoma or carcinoma samples showed a positive inhibin-alpha immunostain. CONCLUSIONS: The tissue microarray/tissue chip technique provides a reliable method to investigate marker expression by offering a rapid, economic and accurate screening of tissue specimens on a large scale. The combined use of A103 and inhibin-alpha is valuable in distinguishing adrenocortical tumor from pheochromocytoma and other metastatic neoplasms.