Targeting and killing of prostate cancer cells using lentiviral constructs containing a sequence recognized by translation factor eIF4E and a prostate-specific promoter

To develop a gene therapy that would selectively kill prostate cancer cells while sparing normal cells, we have constructed lentiviral vectors that contain a therapeutic gene with a short DNA sequence in the 5'-untranslated region (UTR) that is recognized by the translation initiation factor, eIF4E, which is often overexpressed in malignant cells. Infection of cancer (LNCaP, PC-3M, DU145, and MCF-7 cells) and noncancer cell lines (BPH-1, 267-B1, Plat-E, and Huvec-c cells) with lentivirus having a CMV-promoter and EGFP reporter resulted in high levels of EGFP expression in all cells, whereas, inclusion of the eIF4E UTR recognition sequence restricted high expression to cancer cells and Plat-E cells, which also express substantial levels of eIF4E. Infection of the cells with lentiviral vectors having this UTR in front of the HSV thymidine kinase suicide gene resulted in differential sensitivity to the killing effects of ganciclovir, with at least 100-fold more drug required to kill noncancer cells than cancer cells. Furthermore, in experiments where the CMV promoter was replaced by the prostate-specific ARR(2)PB promoter, the killing effects of ganciclovir were restricted to prostate cancer cells and not seen in nonprostate cancer cells. Our results indicate that combined translational regulation, by incorporation of an eIF4E-UTR recognition sequence into a therapeutic gene, together with transcriptional regulation with a prostate-specific promoter, may provide a means to selectively destroy prostate cancer cells while sparing normal prostate cells.

Low meprin alpha expression differentiates primary ovarian mucinous carcinoma from gastrointestinal cancers that commonly metastasise to the ovaries

BACKGROUND

Currently, no specific immunohistochemical markers are available to differentiate primary mucinous epithelial ovarian cancer (MOC) from adenocarcinomas originating at other sites that have metastasised to the ovary, which may have an impact on patient management and prognosis.

AIM

To investigate the expression of two intestinal markers, galectin 4 and meprin alpha, in mucinous carcinomas of the ovary and gastrointestinal tract.

METHODS

Using immunohistochemical analysis, the expression of galectin 4 and meprin alpha was investigated in 10 MOCs and in 38 mucinous adenocarcinomas of colon, pancreas, stomach and appendix, the most common sites of origin of ovarian metastases.

RESULTS

Total cytoplasmic galectin 4 expression was relatively consistent between the different carcinomas. Membranous meprin alpha expression was significantly lower in MOCs compared with gastrointestinal carcinomas. Moreover, meprin alpha expression showed greater discrimination between the ovarian and gastrointestinal carcinomas than the cytokeratins CK7 and CK20, the current standard immunohistochemical markers used to determine the tissue origin of mucinous carcinomas involving the ovaries.

CONCLUSIONS

Meprin alpha is a useful additional marker in differentiating primary from secondary mucinous adenocarcinomas of the ovary.

EELS study of niobium carbo-nitride nano-precipitates in ferrite

Micro-alloying steels allow higher strength to be achieved, with lower carbon contents, without a loss in toughness, weldability or formability through the generation of a fine ferrite grain size with additional strengthening being provided by the fine scale precipitation of complex carbo-nitride particles. Niobium is reported to be the most efficient micro-alloying element to achieve refinement of the final grain structure. A detailed microscopic investigation is one of the keys for understanding the first stages of the precipitation sequence, thus transmission electron microscopy (TEM) is required. Model Fe-(Nb,C) and Fe-(Nb,C,N) ferritic alloys have been studied after annealing under isothermal conditions. However the nanometre scale dimensions of the particles makes their detection, structural and chemical characterization delicate. Various imaging techniques have then been employed. Conventional TEM (CTEM) and high resolution TEM (HRTEM) were used to characterise the morphology, nature and repartition of precipitates. Volume fractions and a statistical approach to particle size distributions of precipitates have been investigated by energy filtered TEM (EFTEM) and high angle annular dark field (HAADF) imaging. Great attention was paid to the chemical analysis of precipitates; their composition has been quantified by electron energy loss spectroscopy (EELS), on the basis of calibrated 'jump-ratios' of C-K and N-K edges over the Nb-M edge, using standards of well-defined compositions. It is shown that a significant addition of nitrogen in the alloy leads to a complex precipitation sequence, with the co-existence of two populations of particles: pure nitrides and homogeneous carbo-nitrides respectively.

A distinct molecular profile associated with mucinous epithelial ovarian cancer

Mucinous epithelial ovarian cancers (MOC) are clinically and morphologically distinct from the other histological subtypes of ovarian cancer. To determine the genetic basis of MOC and to identify potential tumour markers, gene expression profiling of 49 primary ovarian cancers of different histological subtypes was performed using a customised oligonucleotide microarray containing >59 000 probesets. The results show that MOC express a genetic profile that both differs and overlaps with other subtypes of epithelial ovarian cancer. Concordant with its histological phenotype, MOC express genes characteristic of mucinous carcinomas of varying epithelial origin, including intestinal carcinomas. Differences in gene expression between MOC and other histological subtypes of ovarian cancer were confirmed by RT–PCR and/or immunohistochemistry. In particular, galectin 4 (LGALS4) was highly and specifically expressed in MOC, but expressed at lower levels in benign mucinous cysts and borderline (atypical proliferative) tumours, supporting a malignant progression model of MOC. Hence LGALS4 may have application as an early and differential diagnostic marker of MOC.

Prenatal detection of unbalanced chromosomal rearrangements by array CGH

BACKGROUND

Karyotype analysis has been the standard method for prenatal cytogenetic diagnosis since the 1970s. Although highly reliable, the major limitation remains the requirement for cell culture, resulting in a delay of as much as 14 days to obtaining test results. Fluorescent in situ hybridisation (FISH) and quantitative fluorescent PCR (QF-PCR) rapidly detect common chromosomal abnormalities but do not provide a genome wide screen for unexpected imbalances. Array comparative genomic hybridisation (CGH) has the potential to combine the speed of DNA analysis with a large capacity to scan for genomic abnormalities. We have developed a genomic microarray of approximately 600 large insert clones designed to detect aneuploidy, known microdeletion syndromes, and large unbalanced chromosomal rearrangements.

METHODS

This array was tested alongside an array with an approximate resolution of 1 Mb in a blind study of 30 cultured prenatal and postnatal samples with microscopically confirmed unbalanced rearrangements.

RESULTS

At 1 Mb resolution, 22/30 rearrangements were identified, whereas 29/30 aberrations were detected using the custom designed array, owing to the inclusion of specifically chosen clones to give increased resolution at genomic loci clinically implicated in known microdeletion syndromes. Both arrays failed to identify a triploid karyotype. Thirty normal control samples produced no false positive results.

CONCLUSIONS

Analysis of 30 uncultured prenatal samples showed that array CGH is capable of detecting aneuploidy in DNA isolated from as little as 1 ml of uncultured amniotic fluid; 29/30 samples were correctly diagnosed, the exception being another case of triploidy. These studies demonstrate the potential for array CGH to replace conventional cytogenetics in the great majority of prenatal diagnosis cases.

Outcomes research in cancer clinical trial cooperative groups: the RTOG model

BACKGROUND

The Radiation Therapy Oncology Group (RTOG), a National Cancer Institute sponsored cancer clinical trials research cooperative, has recently formed an Outcomes Committee to assess a comprehensive array of clinical trial endpoints and factors impacting the net effect of therapy.

METHODS

To study outcomes in a consistent, comprehensive and coordinated manner, the RTOG Outcomes Committee developed a model to assess clinical, humanistic, and economic outcomes important in clinical trials.

RESULTS

This paper reviews how the RTOG incorporates outcomes research into cancer clinical trials, and demonstrates utilization of the RTOG Outcomes Model to test hypotheses related to non-small-cell lung cancer (NSCLC). In this example, the clinical component of the model indicates that the addition of chemotherapy to radiotherapy (RT) improves survival but increases the risk of toxicity. The humanistic component indicates that esophagitis is the symptom impacting quality of life the greatest and may outweigh the benefits in elderly (> or =70 years) patients. The economic component of the model indicates that accounting for quality-adjusted survival, concurrent chemoRT for the treatment of NSCLC is within the range of economically acceptable recommendations.

CONCLUSION

The RTOG Outcomes Model guides a comprehensive program of research that systematically measures a triad of endpoints considered important to clinical trials research.

The DNA sequence and comparative analysis of human chromosome 10

The finished sequence of human chromosome 10 comprises a total of 131,666,441 base pairs. It represents 99.4% of the euchromatic DNA and includes one megabase of heterochromatic sequence within the pericentromeric region of the short and long arm of the chromosome. Sequence annotation revealed 1,357 genes, of which 816 are protein coding, and 430 are pseudogenes. We observed widespread occurrence of overlapping coding genes (either strand) and identified 67 antisense transcripts. Our analysis suggests that both inter- and intrachromosomal segmental duplications have impacted on the gene count on chromosome 10. Multispecies comparative analysis indicated that we can readily annotate the protein-coding genes with current resources. We estimate that over 95% of all coding exons were identified in this study. Assessment of single base changes between the human chromosome 10 and chimpanzee sequence revealed nonsense mutations in only 21 coding genes with respect to the human sequence.

Elevated serum insulin-like growth factor binding protein-2 as a prognostic marker in patients with ovarian cancer

PURPOSE

The purpose of this research was to examine the diagnostic and prognostic significance of elevated serum insulin-like growth factor binding protein (IGFBP)-2 levels in women with ovarian cancer from diagnosis through treatment to relapse or remission.

EXPERIMENTAL DESIGN

Serum collected pre- and postoperatively in women newly diagnosed with ovarian cancer, during adjuvant chemotherapy cycles, at 6 months follow-up and at relapse was analyzed for IGFBP-2. Control serum was from women undergoing pelvic or abdominal surgery for benign ovarian disease or nonovarian pathology.

RESULTS

IGFBP-2 at diagnosis was significantly elevated (P < 0.0001) in women with ovarian cancer (887 +/- 62 ng/ml) compared with benign controls (337 +/- 25 ng/ml), and women undergoing nonovarian surgery (439 +/- 49 ng/ml) and correlated positively with tumor stage and cellular differentiation but not with CA125. Unexpectedly, IGFBP-2 levels increased additionally 1-week postoperatively in ovarian cancer patients (1581 +/- 90 ng/ml; P = 0.0027) as well as controls (977 +/- 95 ng/ml; P < 0.0001) and was higher in women who had suboptimal debulking compared with optimal debulking of their tumor. IGFBP-2 levels returned to normal in women without evidence of progressive disease, but remained significantly elevated in women who later relapsed. Patients with IGFBP-2 levels in the highest tertile at diagnosis had a significantly shorter progression-free interval and overall survival.

CONCLUSION

In ovarian cancer IGFBP-2 is elevated at diagnosis, and corresponds to stage and histology with patients in the highest tertile of IGFBP-2 more likely to relapse and have a poorer outlook. Identification of these patients at diagnosis may allow more individualized, aggressive adjuvant treatment and follow-up, and IGFBP-2 may therefore be an important additional prognostic marker in this disease.

Primary pulmonary lymphangiectasis in a premature infant: resolution following intensive care

Primary pulmonary lymphangiectasis is a rare disease, often described as fatal within the neonatal period. We report on an infant who developed severe bilateral chylous pleural effusions with computed tomography (CT) features of pulmonary lymphangiectasis. She recovered spontaneously with supportive treatment only. We discuss aspects of her intensive care which might have contributed to the good outcome, and conclude that modern intensive care may allow spontaneous recovery in conditions described in the literature as having a very poor outcome.

A luxCDABE-based bioluminescent bioreporter for the detection of phenol

A bioluminescent reporter strain, Acinetobacter sp. DF4-8, was constructed for the detection of phenol by inserting a mopR-like promoter upstream of the Vibrio fischeri bioluminescent luxCDABE gene cassette in a modified mini-Tn5 construct. When introduced into the chromosome of Acinetobacter sp. DF4, the bioreporter produced a sensitive bioluminescent response to phenol at concentrations ranging from 2.5 to 100 ppm. This response was linear (R(2)=0.986) in the range from 20 to 90 ppm. A significant bioluminescent response was also recorded when strain DF4-8 was incubated with slurries from aged, phenol-contaminated soil.

Castleman's disease: an unusual cause of mediastinal mass and anemia

We reported a case of thoracic localized, mixed variant, Castleman's Disease (angiofollicular lymph node hyperplasia) with a favourable clinical course presenting with mediastinal mass, microcytic anemia, mild thrombocytosis, polyclonal hyper-gammaglobulinaemia and without symptoms. Castleman's Disease must be always considered in the differential diagnosis of solitary mediastinal masses. Transthoracic fine needle aspiration cytology is usually nondiagnostic; in fact, cytologically, Castleman's Disease can be confused with other mediastinal lymphoproliferative disorders (such as thymomas or lymphomas). The optimal therapeutic approach is unknown but a complete surgical resection is treatment of choice for localized disease.