Novel mRNA isoforms and mutations of uridine monophosphate synthetase and 5-fluorouracil resistance in colorectal cancer.

The drug fluorouracil (5-FU) is a widely used antimetabolite chemotherapy in the treatment of colorectal cancer. The gene uridine monophosphate synthetase (UMPS) is thought to be primarily responsible for conversion of 5-FU to active anticancer metabolites in tumor cells. Mutation or aberrant expression of UMPS may contribute to 5-FU resistance during treatment. We undertook a characterization of UMPS mRNA isoform expression and sequence variation in 5-FU-resistant cell lines and drug-naive or -exposed primary and metastatic tumors. We observed reciprocal differential expression of two UMPS isoforms in a colorectal cancer cell line with acquired 5-FU resistance relative to the 5-FU-sensitive cell line from which it was derived. A novel isoform arising as a consequence of exon skipping was increased in abundance in resistant cells. The underlying mechanism responsible for this shift in isoform expression was determined to be a heterozygous splice site mutation acquired in the resistant cell line. We developed sequencing and expression assays to specifically detect alternative UMPS isoforms and used these to determine that UMPS was recurrently disrupted by mutations and aberrant splicing in additional 5-FU-resistant colorectal cancer cell lines and colorectal tumors. The observed mutations, aberrant splicing and downregulation of UMPS represent novel mechanisms for acquired 5-FU resistance in colorectal cancer.

The serine/threonine kinase Pim-2 is a novel anti-apoptotic mediator in myeloma cells.

Bone marrow stromal cells (BMSCs) and osteoclasts (OCs) confer multiple myeloma (MM) cell survival through elaborating factors. We demonstrate herein that IL-6 and TNF family cytokines, TNFα, BAFF and APRIL, but not IGF-1 cooperatively enhance the expression of the serine/threonine kinase Pim-2 in MM cells. BMSCs and OCs upregulate Pim-2 expression in MM cells largely via the IL-6/STAT3 and NF-κB pathway, respectively. Pim-2 short interfering RNA reduces MM cell viability in cocultures with BMSCs or OCs. Thus, upregulation of Pim-2 appears to be a novel anti-apoptotic mechanism for MM cell survival. Interestingly, the mammalian target of rapamycin inhibitor rapamycin further suppresses the MM cell viability in combination with the Pim-2 silencing. The Pim inhibitor (Z)-5-(4-propoxybenzylidene) thiazolidine-2, 4-dione and the PI3K inhibitor LY294002 cooperatively enhance MM cell death. The Pim inhibitor suppresses 4E-BP1 phosphorylation along with the reduction of Mcl-1 and c-Myc. Pim-2 may therefore become a new target for MM treatment.

Resuspension of DNA sequencing reaction products in agarose increases sequence quality on an automated sequencer.

We are investigating approaches to increase DNA sequencing quality. Since a majorfactor in sequence generation is the cost of reagents and sample preparations, we have developed and optimized methods to sequence directly plasmid DNA isolated from alkaline lysis preparations. These methods remove the costly PCR and post-sequencing purification steps but can result in low sequence quality when using standard resuspension protocols on some sequencing platforms. This work outlines a simple, robust, and inexpensive resuspension protocol for DNA sequencing to correct this shortcoming. Resuspending the sequenced products in agarose before electrophoresis results in a substantial and reproducible increase in sequence quality and read length over resuspension in deionized water and has allowed us to use the aforementioned sample preparation methods to cut considerably the overall sequencing costs without sacrificing sequence quality. We demonstrate that resuspension of unpurified sequence products generated from template DNA isolated by a modified alkaline lysis technique in low concentrations of agarose yields a 384% improvement in sequence quality compared to resuspension in deionized water. Utilizing this protocol, we have produced more than 74,000 high-quality, long-read-length sequences from plasmid DNA template on the MegaBACET 1000 platform.

A case of well-differentiated minute hepatocellular carcinoma with extrahepatic metastasis.

A rare case of well-differentiated minute hepatocellular carcinoma (HCC) metastasizing to distant sites in a 77-year-old man with hepatitis C virus (HCV)-related cirrhosis is presented. Ultrasonography (US) disclosed a 9 mm hypoechoic lesion in segment seven (S7) of the liver, although computed tomography (CT), magnetic resonance imaging (MRI) and angiography did not reveal any space-occupying lesion. Ultrasound-guided biopsy showed the histological features of well-differentiated HCC. A plain film of the abdomen and CT revealed osteolytic changes in the sacrum and the lumbar vertebra. Ultrasound-guided biopsy of the sacrum revealed well-to-moderately differentiated HCC metastasizing from the liver. Percutaneous ethanol injection therapy (PEIT) effected complete response and completely eliminated the abnormal findings on US. Three months after PEIT, metastasis to the thoracic vertebra was revealed by CT, despite negative alpha-fetoprotein-mRNA in serum. This is the first report describing a well-differentiated HCC with metastatic potential. Further studies may provide insights into metastasis of well-differentiated HCC.

Effect of pulsed output ultrasound on the transdermal absorption of indomethacin from an ointment in rats.

The effect of pulsed output ultrasound (1 MHz) with on/off ratios of 1:2, 1:4 and 1:9 on transdermal absorption of indomethacin from an ointment was studied in rats. Ultrasound energy was supplied for between 10 and 19 min at a range of intensities (1.0-2.5 W.cm-2), energy levels commonly used for therapeutic purposes. The on/off pulsed ratio, intensity and the time of application were found to play an important role in the transdermal phonophoretic delivery system of indomethacin; 1:2 pulsed output ultrasound appeared to be the most effective in improving the transdermal absorption. The highest penetration was observed at an intensity of 1.0 W.cm-2 and application time of 15 min. With pulsed output it was possible to use higher intensities of ultrasound without increasing skin temperature or damaging skin.

Functional analysis of vif genes derived from various primate immunodeficiency viruses.

Replication property in cells of human and simian immunodeficiency viruses (HIVs and SIVs) lacking intact vif gene was evaluated. Of 10 vif mutants constructed in vitro of the major four HIV/SIV groups, only those derived from HIV-1 and HIV-2/SIVmac displayed replication defect. The cell lines non-permissive for the vif mutants of HIV-1 and SIVmac were found to be different. To determine whether Vif is exchangeable between HIV-1 and SIVmac, chimeric virus clones with respect to the vi gene were constructed and virus replication in the cells non-permissive for the vif mutant viruses was monitored. Productive infection in these cells of chimeric viruses clearly indicated that Vif is functionally exchangeable, and that Vifs of different virus origin act through a similar mechanism.

Antiviral activity of lignans and their glycosides from Justicia procumbens.

Ten antiviral lignans, seven known (justicidins A, B, C and D, diphyllin, diphyllin apioside and diphyllin apioside-5-acetate) and three new compounds, justicidinosides A (justicidin C 6'-O-glucoside), B (justicidin A 6'-O-glucoside) and C (justicidin B 6'-O-glucoside), were isolated from a methanolic extract of the aerial parts of Justicia procumbens var. leucantha. Justicidins A and B, diphyllin, diphyllin apioside and diphyllin apioside-5-acetate showed strong antiviral activity (the MIC were less than 0.25 microgram ml-1, respectively) against vesicular stomatitis virus and low cytotoxicity (the MTC were larger than 31 micrograms ml-1, respectively) against cultured rabbit lung cells (RL-33).

Cytotoxic xanthones from Garcinia hanburyi.

Eleven novel cytotoxic xanthones, gambogin, morellin dimethyl acetal, isomoreollin B, moreollic acid, gambogenic acid, gambogenin, isogambogenin, desoxygambogenin, gambogenin dimethyl acetal, gambogellic acid and hanburin were isolated together with four known xanthones, gambogic acid, isomorellin, morellic acid and desoxymorellin, from the dry latex of Garcinia hanburyi. The structures were elucidated by a detailed spectroscopic analysis.

Effects of erucic acid therapy on Japanese patients with X-linked adrenoleukodystrophy.

Ten Japanese boys with childhood adrenoleukodystrophy (ALD), one adult patient with adrenomyeloneuropathy (AMN), and two presymptomatic ALD boys were treated with dietary erucic acid (C22:1) for more than 12 months; except in a case of childhood ALD patient who died 7 months after beginning erucic acid therapy. During erucic acid therapy, the serum levels of very long-chain fatty acid (VLCFA) (C24:0/C22:0) decreased within 1-2 months in all patients, and these levels in four of the patients decreased to the normal range. Neurological examination and MRI findings in all 10 of the childhood ALD patients showed progression of the disease while they were receiving the dietary therapy. However, the mean interval between the onset of awkward gait and a vegetative state in diet-treated patients was significantly longer than that in the untreated patients. One AMN patient showed slight improvement of spastic gait and lessened pain in the lower limbs due to spasticity. The two presymptomatic ALD boys remained intact on clinical examination and on MRI findings for 38 and 23 months, respectively, after starting the diet.

Thyroid cancer in a case with the Alagille syndrome.

A 19-year-old woman with the Alagille syndrome developed papillary thyroid carcinoma with lung metastasis. She was diagnosed as having Alagille syndrome at the age of 8. Following total thyroidectomy and lymph nodes dissection, iodine-131 therapy was conducted for local and distant metastases. This is the first report of a case of thyroid cancer accompanying Alagille syndrome.

Balanced complex rearrangement involving chromosomes 8, 9, and 12 in a normal mother, derivative chromosome 9 with recombinant chromosome 12 in her daughter with minor anomalies.

We report on a 19-month-old girl with a derivative chromosome 9 and a recombinant chromosome 12 resulting from a maternal balanced complex rearrangement involving chromosomes 8, 9, and 12. The karyotype of the phenotypically normal mother was 46,XX,t(8;12) (9;12) (8qter-->8p23::12q12-->12q 15::9q32-->9qter;9pter-->9q32::12q15--> 12qter; 12pter-->12q12::8p23-->8pter). The child's karyotype was 46,XX,-9,-12, +der(9) (9pter-->9q32::12q15-->12qter), +rec(12) (12pter-->12q15::9q32-->9qter) mat. The child had severe growth retardation, minor anomalies including trigonocephaly, hypertelorism, broad nasal root, apparently low-set and posteriorly angulated ears, triangular face, pectus carinatum, clinodactyly of fifth fingers, and almost normal psychomotor development. To the best of our knowledge, there have been only 3 previous reports of recombination derived from parental complex chromosome rearrangements. In the recombination products, the chromosomes were apparently balanced and the offspring had no clinical abnormalities. The present case exhibited abnormalities and may have a submicroscopic aberration of 12q arising from crossing over during maternal meiotic pairing, although her chromosomes appeared to be balanced.

Improvement of clinical and MRI findings in a boy with adrenoleukodystrophy by dietary erucic acid therapy.

A 5-year-old boy with adrenoleukodystrophy, with clinical symptoms of visual, mental and motor disturbances which progressed rapidly, was treated with Lorenzo's oil consisting 1 volume of glyceryl trierucate and 4 volumes of glyceryl trioleate. Five months after initiation of this therapy, ability to swallow was enhanced and T2-weighted magnetic resonance imaging of the brain revealed regression of high intensity area of the parieto-occipital white matter.