Dopamine and cyclic adenosine monophosphate-regulated phosphoprotein with an apparent Mr of 32000 promotes colorectal cancer growth.

BACKGROUND: Dopamine and cyclic adenosine monophosphate (cAMP)-regulated phosphoprotein with an apparent Mr of 32000 (DARPP-32) is a protein that is involved in regulating dopamine and cAMP signaling pathways in the brain. However, recent studies have shown that DARPP-32 is also expressed in other tissues, including colorectal cancer (CRC), where its function is not well understood. AIM: To explore the effect of DARPP-32 on CRC progression. METHODS: The expression levels of DARPP-32 were assessed in CRC tissues using both quantitative polymerase chain reaction and immunohistochemistry assays. The proliferative capacity of CRC cell lines was evaluated with Cell Counting Kit-8 and 5-ethynyl-2'-deoxyuridine assays, while apoptosis was measured by flow cytometry. The migratory and invasive potential of CRC cell lines were determined using wound healing and transwell chamber assays. In vivo studies involved monitoring the growth rate of xenograft tumors. Finally, the underlying molecular mechanism of DARPP-32 was investigated through RNA-sequencing and western blot analyses. RESULTS: DARPP-32 was frequently upregulated in CRC and associated with abnormal clinicopathological features in CRC. Overexpression of DARPP-32 was shown to promote cancer cell proliferation, migration, and invasion and reduce apoptosis. DARPP-32 knockdown resulted in the opposite functional effects. Mechanistically, DARPP-32 may regulate the phosphoinositide 3-kinase (PI3K)/AKT signaling pathway in order to carry out its biological function. CONCLUSION: DARPP-32 promotes CRC progression via the PI3K/AKT signaling pathway.

Genetic Characteristics of Resectable Colorectal Cancer with Pulmonary Metastasis.

The lung is the most common extra-abdominal metastasis site of colorectal cancer (CRC). This study aimed to investigate the genetic variation of pulmonary metastases (PM) and primary tumors in resectable CRC. The clinical data of 410 patients with PM after CRC surgery and 33 paraffin-embedded tissue samples from January 2012 to July 2019 in our hospital were collected retrospectively. Next, 450-panel gene detection technologies based on next-generation sequencing (NGS) were used to analyze the changes in the gene map and the overall variation in cancer-related genes in PM and primary tumors. After quality control, 19 samples were included in the final gene analysis. The results showed that APC (89.5%), TP53 (89.5%), and KRAS (53%) were the most common mutations in PM and primary tumors, but the gene amplification variation was enriched in primary tumors (4.6% vs. 11.4%). KRAS G12D was the most common site variation of the KRAS gene in both PM and primary tumors of CRC. There was no hotspot mutation in the TP53 locus in CRC, and the TP53 mutation in the PM was consistent with that in the primary lesion. The microsatellite instability (MSI) levels of 10 patients were MSS. The mean tumor mutation burden (TMB) of the primary tumor (5.3 muts·Mb-1) was slightly higher than that of metastasis (5.0 muts·Mb-1). In our institution, the genetic characteristics of resectable PM from CRC may be highly consistent with those of the primary tumor.

The influence of corneal astigmatism on retinal nerve fiber layer thickness and optic nerve head parameter measurements by spectral-domain optical coherence tomography.

BACKGROUND: To evaluate the influence of corneal astigmatism (CA) on retinal nerve fiber layer (RNFL) thickness and optic nerve head(ONH) parameters measured with spectral-domain optical coherence tomography (OCT) in high myopes patients before refractive surgery. METHODS: Seventy eyes of 35 consecutive refractive surgery candidates were included in this study. The mean age of the subjects was 26.42 ± 6.95 years, the average CA was -1.17 diopters (D; SD 0.64; range -0.2 to-3.3D), All subjects in this study were WTR CA. 34 eyes were in the normal CA group with a mean CA was -0.67 ± 0.28D, 36 eyes were in the high CA group with an average CA of -1.65 ± 0.49D. All subjects underwent ophthalmic examination and imaging with the Cirrus HD OCT. RESULTS: No significant difference was noted in the average cup-to-disk ratio, vertical cup-to-disk ratio and cup volume (all P values > 0.05). Compared with the normal CA group, the high CA group had a larger disc area and rim area, thinner RNFL thickness in the temporal quadrant, and the superotemporal and inferotemporal peaks were farther to the temporal horizon (All P values < 0.05). There were no significant differences between the two groups in global average RNFL thickness, as well as superior, nasal and inferior quadrant RNFL thickness (all P values > 0.05). CONCLUSIONS: The degree of with-the-rule CA should be considered when interpreting ONH parameters and peripapillary RNFL thickness measured by the Cirrus HD OCT. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1148475676881895.

Synthesis and antitumor activity of 3-methyl-4-oxo-3,4-dihydroimidazo [5,1-d][1,2,3,5]tetrazine-8-carboxylates and -carboxamides.

Seventeen novel 3-methyl-4-oxo-3,4-dihydroimidazo[5,1-d][1,2,3,5]tetrazine-8-carboxylate and -carboxamide derivatives were synthesized and evaluated for their growth inhibition in seven human solid tumor and a human leukemia HL-60 cell lines. Compound IVa showed more activity than the other compounds and the positive control temozolomide. In the presence of 40 µg/mL of IVa, the survival rate of all tested tumor cells was less than 10%. Esters displayed more potent antitumour activity than amides and temozolomide against HL-60 cells. These compounds also exhibited considerably enhanced water-solubility.

[Hydroquinone inhibits NF-kappaB expression in human bone marrow stromal cells in vitro].

This study was aimed to investigate whether hydroquinone (HQ) can inhibit NF-kappaB expression activated by phorbol myristate acetate (PMA), and to explore the relationship between the mechanism and the hematology toxicity of benzene tentatively. The human bone marrow stromal cells (BMSC) were harvested by in vitro culture and their change of morphology were observed. The activity and protein expression of NF-kappaB p65 extracted from those BMSC were measured with immunohistochemistry and TransAM P65 kit. The results showed that in cells exposed to HQ, P65 transferred from cell nucleus to cytoplasma around cell nucleus and its concentration lowered by immunohistochemistry. And TransAM P65 kit assay revealed that HQ effects at different concentrations were distinctive at respective time. The detected parameters in 100 micromol/L HQ group were significantly different from control group after exposure for 72 hours. But the parameters at different time in micromol/L HQ group were not obviously different. It is concluded that hydroquinone can inhibit NF-kappaB activated by PMA in BMSCs culture. This kind of inhibitory action correlated with the concentration of HQ and exposure time.

PGE2 up-regulates vascular endothelial growth factor expression in MKN28 gastric cancer cells via epidermal growth factor receptor signaling system.

AIM: 1) To evaluate the effect of prostaglandin E2 (PGE2) on the regulation of vascular endothelial growth factor (VEGF) expression in gastric MKN28 cells, and 2) to investigate the role of the epidermal growth factor receptor (EGFR) signal transduction pathway in any effect exerted by PGE2 on VEGF expression. METHODS: MKN28 cells were incubated with the vehicle (control) or with PGE2 in the presence or absence of AG1478, a selective inhibitor of EGFR tyrosine kinase, or PD098059, a selective inhibitor of the kinase responsible for ERK2 phosphorylation (mitogen-activated protein (MAP)/extracellular signal-regulated kinase (ERK)). Real-time quantitative polymerase chain reaction and Western blot analysis were used to evaluate VEGF mRNA and protein expression. The activity of EGFR and ERK2 was measured by Western blot analysis. RESULTS: PGE2 significantly up-regulated VEGF mRNA and protein expression and increased the activation of EGFR and ERK2. Incubation of MKN28 cells with AG1478 significantly reduced PGE2-induced EGFR activity, ERK2 activity, and VEGF mRNA and protein expression. Meanwhile, incubation of MKN28 with PD098059 reduced PGE2-induced ERK2 activity and VEGF mRNA and protein expression, but had no effect on EGFR activity. CONCLUSION: Our data suggested that PGE2 up-regulates VEGF expression in gastric cancer cells via transactivation of EGFR-MAPK signaling pathways, which may be mechanisms underlying the contribution of COX-2 to tumor angiogenesis in gastric cancer.

[The apoptosis-inducing activity of human selenoprotein P shorter isoform].

OBJECTIVE: Human selenoprotein P (HSelP) is unique protein that contains 10 selenocysteines encoded by 10 inframe UGA, which typically function as stop codon. The function of HSelP remains unclear, in part due to the inability to express it by gene recombinant technique. This study is to investigate expression and purification of recombinant HSelP in prokaryotic expression system, and its activity to induce apoptosis in vitro. METHODS: The shorter HSelP isoform was cloned. After the selenocysteine (SeCys) at 40th position from N terminus of the HSelP shorter isoform was mutated into cysteine by PCR, it was expressed in E. coli. The expressed product was purified with DEAE column and identified by Western blot. Subsequently, its function on induction of mitochondrial apoptotic activity was studied. RESULTS: The mutant HSelP shorter isoform expressed in prokaryotic system was purified by DEAE column to 90% homogeneity. The purified product, HSelP280m, induced the opening of mitochondrial permeability transition pore (PTP) and decreased the transmembrane potential in a dose-dependent manner. These events could be abolished by PTP specific inhibitors. CONCLUSION: HSelP280m can induce the opening of mitochondrial PTP, which provides a basis for investigating the structure and function of recombinant HSelP.

[Redox reactions of Sep15 and its relationship with tumor development].

BACKGROUND & OBJECTIVE: Sep15 is a selenium-containing protein identified in 1998. This protein may be involved in cancer etiology and it may have redox function. The objective of this study was to investigate the relationship between the redox function of Sep15 and tumor development. METHODS: The full-length DNA sequence of Sep15 was obtained by RT-PCR and then recombined to eukaryotic expression vector pcDNA3.1(+). The BEL-7402- Sep15 cell line, which expressed the high levels of Sep15 by transfecting the cultured hepatocarcinoma cell line BEL-7402 with pcDNA3.1-Sep15 was generated. From morphologic investigation, cell growth curve, clone formation and nude mice tumor growth curve, the relationship between Sep15 and hepatocarcinoma cell line BEL-7402 was determined. Furthermore, the redox reaction of sep15 was detected by MTT assay. RESULTS: There was no distinct effect of transfection of Sep15 gene on BEL-7402-Sep15 cell. The cell survival rate was drastically different between BEL-7402-Sep15 cell and both BEL-7402- pcDNA cell and BEL-7402-Sep15 cell after foreign H2O2 reactive oxygen stress (P<0.05). CONCLUSION: Transfecting Sep15 gene did not influence the growth characteristics of BEL-7402 cell line and Sep15 may have redox function.

[Research of the anti-tumor effect of human endostatin mediated by recombinant adeno-associated virus].

BACKGROUND & OBJECTIVE: It was reported that endostatin could inhibit tumor angiogenesis, then inhibit the growth and metastasis of tumor. However, there was few report about the treatment usage of endostatin. This study was designed to explore the effect of endostatin mediated with recombinant adeno-associated virus(rAAV) on tumor growth and metastasis. METHODS: To obtain the endostatin gene complete cDNA by RT-PCR, and clone it into the plasmid pSNAV and package the recombinant rAAV-SS-endostatin; to analyze its anti-tumor effect through animal experiments. RESULTS: In the B16F10 melanoma tumor model, C57BL/6 mice were inoculated with 10(11)TU rAAV-SS-endostatin i.m. injection, which the inhibition rate was 57.1%; In the lung metastatic model, the inhibition rate of metastases was 70.7%. CONCLUSIONS: rAAV-SS-endostatin can effectively inhibit tumor growth and metastasis.