Promoter analysis and transcriptional regulation of human carbonic anhydrase VIII gene in a MERRF disease cell model

Carbonic Anhydrase VIII (CAVIII) Gene Mediated Colorectal Cancer Growth and Angiogenesis through Mediated miRNA 16-5p

Carbonic anhydrase VIII (CAVIII) is a member of the CA family, while CA8 is the oncogene. Here we observed increased expression of CAVIII with high expression in colorectal cancer tissues. CAVIII is also expressed in more aggressive types of human colorectal cancer cells. Upregulated CAVIII expression in SW480 cell lines increased vascular endothelial growth factor (VEGF) and reduced miRNA16-5p. Conversely, knockdown of the CAVIII results in VEGF decline by up-regulated miRNA16-5p. Moreover, the collection of different grades of CAVIII expression CRC cells supernatant co-culture with endothelial progenitor cells (EPCs) promotes the ability of tube formation in soft agar and migration in the Transwell experiment, indicating that CAVIII might facilitate cancer-cell-released VEGF via the inhibition of miRNA16-5p signaling. Furthermore, in the xenograft tumor angiogenesis model, knockdown of CAVIII significantly reduced tumor growth and tumor-associated angiogenesis. Taken together, our results prove that the CAVIII/miR-16-5p signaling pathway might function as a metastasis suppressor in CRC. Targeting CAVIII/miR-16-5p may provide a strategy for blocking its metastasis.

Discovery of new carbonic anhydrase IX inhibitors as anticancer agents by toning the hydrophobic and hydrophilic rims of the active site to encounter the dual-tail approach

The hydrophobic and the hydrophilic rims in the active site of human carbonic anhydrase IX (hCA IX) which as well contains a zinc ion as part of the catalytic core, were simultaneously matched to design and synthesize potent and selective inhibitors using a dual-tail approach. Seventeen new compounds, 5a-q, were designed to have the benzenesulfonamide moiety as a zinc binding group. In addition, N-substituted hydrazone and N-phenyl fragments were chosen as the hydrophilic and hydrophobic parts, respectively to achieve favorable interactions with the corresponding halves of the active site. All synthesized compounds successfully suppressed the CA IX, with IC₅₀ values in nanomolar range from 13.3 to 259 nM. Compounds, 5h, 5c, 5m, 5e, and 5k were the top-five compounds efficiently inhibited the tumor-related CA IX isoform in the low nanomolar range (K_I = 13.3, 22.6, 25.8, 26.9 and 27.2 nM, respectively). The target compounds 5a-q developed remarkable selectivity toward the tumor-associated isoforms (hCA IX and XII) over the off-target isoforms (hCA I and II). Furthermore, they were assessed for their anti-proliferative activity, according to US-NCI protocol, against a panel of fifty-nine cancer cell lines. Compounds 5d, 5k and 5o were passed the criteria for activity and scheduled automatically for evaluation at five concentrations with 10-fold dilutions. Compound 5k exhibited significant in vitro anticancer activity with GI₅₀-MID; 8.68 μM compared to compounds 5d and 5o with GI₅₀-MID; 25.76 μM and 34.97 μM respectively. The most selective compounds 5h and 5k were further screened for their in vitro cytotoxic activity against SK-MEL-5, HCC-2998 and RXF 393 cancer cell lines under hypoxic conditions. Furthermore, 5k was screened for cell cycle disturbance, apoptosis induction and intracellular reactive oxygen species (ROS) production in SK-MEL-5 cancer cells. Finally, molecular docking studies were performed to gain insights for the plausible binding interactions and affinities for selected compounds within hCA IX active site.

Developing a gene panel for pharmacoresistant epilepsy: a review of epilepsy pharmacogenetics

Evaluating genes involved in the pharmacodynamics and pharmacokinetics of epilepsy drugs is critical to better understand pharmacoresistant epilepsy. We reviewed the pharmacogenetics literature on six antiseizure medicines (carbamazepine, perampanel, lamotrigine, levetiracetam, sodium valproate and zonisamide) and compared the genes found with those present on epilepsy gene panels using a functional annotation pathway analysis. Little overlap was found between the two gene lists; pharmacogenetic genes are mainly involved in detoxification processes, while epilepsy panel genes are involved in cell signaling and gene expression. Our work provides support for a specific pharmacoresistant epilepsy gene panel to assist antiseizure medicine selection, enabling personalized approaches to treatment. Future efforts will seek to include this panel in genomic analyses of pharmacoresistant patients, to determine clinical utility and patient treatment responses.

CA8 promotes RCC proliferation and migration though its expression level is lower in tumor compared to adjacent normal tissue

Chemotherapy and radiotherapy are not as successful in the case of renal cell carcinoma (RCC) although some targeted drugs were approved for RCC therapy recently. Analysis of whole genomic data will lead to improvements in understanding RCC and identifying novel anticancer targets. Here, we found the differential mRNA expression and copy number variation (CNV) of Carbonic anhydrase-related protein VIII (CA8) gene in RCC through integrated bioinformatics analysis of TCGA database, which was confirmed in 5 cases of samples collected from RCC patients who underwent radical nephrectomy by analysis of CA8 mRNA and protein levels using RT-PCR immunohistochemical assay. However, we got a completely opposite result that CA8 promoted RCC progression, those are CA8 overexpression promoted the proliferative and migratory ability of Caki-1 and 769-P cells in vitro as determined with MTT and transwell assay, and CA8 overexpression could also promote Caki-1 xenograft growth in BALB/C‑nu/nu mice. On the contrary, CA8-knockdown reduced Caki-1 and 769-P cell proliferation and migration. Moreover, knockdown of CA8 decreased pAKT and MMP2 protein levels in Caki-1 cells while overexpressing CA8 increased pAKT and MMP2. In conclusion, we showed that CA8 promoted RCC cell proliferation and migration, but it was down-regulated in RCC, which requires an additional mechanism study.

Protective roles of carbonic anhydrase 8 in Machado-Joseph Disease

Machado-Joseph disease (MJD)/Spinocerebellar ataxia type 3 (SCA3) is an inherited neurodegenerative disease that can lead to a regression of motor coordination and muscle control in the extremities. It is known that expansion of CAG repeats encodes abnormally long polyQ in mutant ataxin-3, the disease protein. It is also noted that mutant ataxin-3 interacts with 1,4,5-trisphosphate receptor type 1 (IP3R1) and induces abnormal Ca²⁺ release. Previously, we have shown a significant increase in the expression of carbonic anhydrase VIII (CA8) in SK-N-SH-MJD78 cells, which are human neuroblastoma cells overexpressing mutant ataxin-3 with 78 glutamine repeats. In the current study, we showed the presence of significantly increased CA8 expression in MJD mouse cerebellum in either early or late disease stage, with a gradual decrease in CA8 expression as the MJD mice naturally aged. By immunofluorescence and immunoprecipitation analysis, we also found that CA8 co-localized and interacted with mutant ataxin-3 in SK-N-SH-MJD78 cells harboring overexpressed CA8 (SK-MJD78-CA8). In addition, we found that SK-MJD78-CA8 cells, as well as cerebellar granule neurons (CGNs) of MJD transgenic (Tg) mouse with overexpressed CA8, were more resistant to reactive oxygen species (ROS) stress than the control cells. Importantly, overexpression of CA8 in SK-MJD78-CA8 cells and in MJD CGNs rescued abnormal Ca²⁺ release and caused an increase in cell survival. In summary, we demonstrate the protective function of CA8 in MJD disease models and speculate that the declining expression of CA8 following an initial increased expression may be related to the late onset phenomenon of MJD.