Determination of distinctive hypomethylated genes in African American colorectal neoplastic lesions

BACKGROUND

Few studies have analyzed progressive demethylation in the path to cancer. This is of utmost importance, especially in populations such as African Americans, who display aggressive tumors at diagnosis, and for whom markers of early neoplastic transformation are needed. Here, we determined hypomethylated targets in the path to colorectal cancer (CRC) using Reduced Representation Bisulfite Sequencing (RRBS).

METHODS

DNA was extracted from fresh frozen tissues of patients with different colon lesions (normal, tubular adenoma, tubulovillous adenoma, and five cancers). RRBS was performed on these DNA extracts to identify hypomethylated gene targets. Alignment, mapping, and methylation analyses were performed. Pathways affected by the hypomethylated gene targets were determined using Ingenuity Pathway Analysis (IPA).

RESULTS

Pairwise analyses of samples led to the identification of the following novel hypomethylated genes: ELMO3 (Engulfment and cell motility 3), SLC6A2 (Solute carrier family 6 member 2), SYNM (Synemin), and HMX2 (Homeobox 2). The ELMO3 promoter was significantly hypomethylated at five CpG sites, SYNM at two CpG sites, SLC6A2 at one CpG site, and the HMX2 gene at one CpG site. IPA placed these genes within important carcinogenic pathways.

CONCLUSIONS

This work provides insight into the role of hypomethylation in colon carcinogenesis in African Americans. The identified targets affected many important pathways, as demonstrated through IPA. These targets might serve as biomarkers for early diagnosis and potential targets for therapy.

Abstract 4323: 1,25-Dihydroxyvitamin D3 inhibits oral squamous cell carcinoma cell growth via microRNA regulation

Objective: Oral squamous cell carcinomas (OSCC) is one of top ten cancers lead to death in USA. This study focused on the impacts of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) treatment on the inhibition of OSCC growth in vitro and the alteration of microRNA (miRNA) expression profile by the treatment.

Materials and Methods: 1,25(OH)2D3-associated apoptosis, cell cycle arrest, and proliferative effect in cultured OSCC cells were assessed using flow cytometry and western blotting methods. miRNA expression profiles were measured using nanoString Sprint Profiller and the Nanostring human miRNA panel. More miRNAs functional pathways were retrieved through bioinformatics using Qiagen IPA system.

Results: 1,25(OH)2D3 was found to inhibit the growth of human JHU-22 OSCC cells in a dose-dependent manner with IC50 of 1.56 x 10-6 M. High levels of apoptotic cells and related biomarkers were obtained when the cells were treated with 1,25(OH)2D3. Over 20 miRNAs were upregulated and 23 downregulated by more than two folds, in 1,25(OH)2D3 treated versus untreated JHU-22 cells. Bioinformatics analysis showed molecular functions of most dysregulated miRNAs. For example, MiR-125b-5p upregulated caspases number 2, 6, 7 in addition to upregulating apoptosis facilitator like BCL-2, BIM, and AIF.

Conclusion: Our data suggested that 1,25(OH)2D3 function as a OSCC inhibiter is through regulating miRNA expression profile and miRNA function directly or indirectly. 1,25(OH)2D3 has potential to be an anticancer agent for OSCC prevention and treatment.

Fold change of top ten unregulated and down regulated miRNAs at nine hour treatment.miRNAControl (C9)Vitamin D (D9)C9/D9hsa-miR-624-3p8283.5hsa-miR-52110272.7hsa-miR-221-5p11292.64hsa-miR-1301-3p7182.57hsa-miR-520a-3p8202.5hsa-miR-153-3p12282.33hsa-miR-122-5p16372.31hsa-miR-120615342.27hsa-miR-125b-5p68615472.26hsa-miR-450b-3p492.25hsa-miR-613219-2.33hsa-miR-147b2611-2.36hsa-miR-525-3p125-2.40hsa-miR-5196-3p+hsa-miR-6732-3p187-2.57hsa-miR-181b-5p+hsa-miR-181d-5p218-2.63hsa-miR-182-3p3212-2.67hsa-miR-941228-2.75hsa-miR-671-3p176-2.83hsa-miR-944186-3.00hsa-miR-1245b-3p246-4.00

Citation Format: Heba Said Ismail Hussein, Wei Wang, Liang Shan, Karl Thompson, Kareem Washington, Gihane Madkour, Xinbin Gu. 1,25-Dihydroxyvitamin D3 inhibits oral squamous cell carcinoma cell growth via microRNA regulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4323.

Randomized Controlled Trial Comparing the Effects of Far-Infrared Emitting Ceramic Fabric Shirts and Control Polyester Shirts on Transcutaneous PO2

Our aim was to confirm earlier studies showing tcPO₂ to be higher under clothing made with polyethylene terephalate (PET) fabric containing ceramic particles (CEL) compared to standard PET fabric. In previous studies PET garments were donned first to avoid possible persistent effects from ceramic particles. This study randomized donning sequence to avoid bias.

Status of LEPR Gene in PCB-exposed Population: A Quick Look

Earlier, we have reported that Polychlorinated Biphenyls (PCBs) exposure in Slovak population has made differential gene expression that has linked to the possibilities of some diseases and disorder development in the studied population. Here we report that down-regulation of LEPR (Leptin receptor) gene in the 45-month children may have been following consequences in developing obesity later in life. A pilot high-throughput qRT-PCR [Taqman Low Density Array (TLDA)] study in a small population also corroborated the gene-expression results, and their pathways underlying the consequences of the diseases, amid further detailed large-scale population validation. The study shows the opportunity of predicting long-term effects of chemical exposures using selected genomic classifiers may reflect exposure effect and risk from environmental toxicants.

Reduced Representation Bisulfite Sequencing Determination of Distinctive DNA Hypermethylated Genes in the Progression to Colon Cancer in African Americans

Background and Aims. Many studies have focused on the determination of methylated targets in colorectal cancer. However, few analyzed the progressive methylation in the sequence from normal to adenoma and ultimately to malignant tumors. This is of utmost importance especially in populations such as African Americans who generally display aggressive tumors at diagnosis and for whom markers of early neoplasia are needed. We aimed to determine methylated targets in the path to colon cancer in African American patients using Reduced Representation Bisulfite Sequencing (RRBS). Methods. Genomic DNA was isolated from fresh frozen tissues of patients with different colon lesions: normal, a tubular adenoma, a tubulovillous adenoma, and five cancers. RRBS was performed on these DNA samples to identify hypermethylation. Alignment, mapping, and confirmed CpG methylation analyses were performed. Preferential hypermethylated pathways were determined using Ingenuity Pathway Analysis (IPA). Results. We identified hypermethylated CpG sites in the following genes: L3MBTL1, NKX6-2, PREX1, TRAF7, PRDM14, and NEFM with the number of CpG sites being 14, 17, 10, 16, 6, and 6, respectively, after pairwise analysis of normal versus adenoma, adenoma versus cancer, and normal versus cancer. IPA mapped the above-mentioned hypermethylated genes to the Wnt/β-catenin, PI3k/AKT, VEGF, and JAK/STAT3 signaling pathways. Conclusion. This work provides insight into novel differential CpGs hypermethylation sites in colorectal carcinogenesis. Functional analysis of the novel gene targets is needed to confirm their roles in their associated carcinogenic pathways.

Abstract 4588: Whole genome hypo- and hyper-methylation sequencing among Africa American patients with colorectal cancer

Background: Colorectal cancer (CRC) involves epigenetic changes including DNA hypomethylation, a paradigm shift in the role of DNA methylation alterations in colorectal carcinogenesis.

Aim: Here we performed Reduced Representation Bisulfite Sequencing (RRBS) on a normal, and a tumor patient's tissue DNA to elucidate hyper- and hypomethylaed target genes in colorectal cancer progression in this population.

Methods: Genomic DNA was isolated from fresh frozen surgical tissues from a patient with normal colon, and from a carcinoma patient. RRBS was performed on these DNA samples for hyper- and hypomethylation targets identification. Alignment, mapping and CpG methylation analyses were performed. Preferential hypomethylated pathways were determined using Ingenuity Pathway Analysis (IPA).

Results: We identified the hyper (6360 CpG sites) and hypo-methylation (4845 CpG sites) status of top genes in the CpG Island within promoter regions (19 and 18 genes respectively). Top hyper- and hypomethylated CpG Island outside promoter regions (16 and 18 genes, respectively) were also identified. Among these top genes, CDH4 and SOX21 were reported to be hypermethylated in CRC and SCUBE2 (112 methylated CpG) mapped by IPA to the Hedgehog, TGF-β, and VEGF Signaling pathways was reported to play a role in breast cancer. Among the top hypomethylated genes, ACOT9 (97 CpGI sites) and RIN2 (40 CpGI sites) might play a significant role in CRC in AAs, since IPA mapped these markers to the Wnt/β-catenin, VEGF and PTEN signaling pathways. ACOT9 was found to play a role in breast cancer.

Conclusion: This work provides insight into differential CpG island hyper- and hypo-methylation profiles in CRC and provides a window into the more complex epigenetic events associated with CRC, including the hypomethylation of known and novel genes. Investigations into the possible roles of the novel gene targets in the context of early and prognostic methylation biomarkers are underway.

Citation Format: Hassan Ashktorab, Afnan Shakoori, Shatha Zarnogi, Xueguang Sun, Sudhir Varma, Edward Lee, Babak Shokrani, Adeinko O. Laiyemo, Kareem Washington, Hassan Brim. Whole genome hypo- and hyper-methylation sequencing among Africa American patients with colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4588. doi:10.1158/1538-7445.AM2015-4588

Race-ethnicity and poverty after spinal cord injury

Objective

Our objective was to examine the relationship between race-ethnicity and poverty status after spinal cord injury (SCI).

Study Design

Secondary analysis of existing data.

Setting

A large specialty hospital in the southeastern United States (US).

Methods

Participants were 2,043 adults with traumatic SCI in the US. Poverty status was measured using criteria from the US Census Bureau.

Results

Whereas only 14% of non-Hispanic White participants were below the poverty level, 41.3% of non-Hispanic Blacks were in poverty. Logistic regression with three different models identified several significant predictors of poverty including marital status, years of education, level of education, age, and employment status. Non-Hispanic Blacks had 2.75 greater odds of living in poverty after controlling for other factors, including education and employment.

Conclusions

We may need to consider quality of education and employment to better understand the elevated risk of poverty among non-Hispanic Blacks in the US.

Hemodynamic correlates of low umbilical cord vitamin D and ionized calcium

Vitamin D deficiency and hypocalcemia are associated with gestational hypertension. Therefore, we hypothesized that umbilical cord [Ca(2+)] and [vitamin D] are correlated with perinatal blood pressures. Mothers and newborns comprised vitamin D sufficient (vitamin D ≥ 50 nM, range 52-111 nM, n = 14), and vitamin D deficient groups (vitamin D < 50 nM, range 13-49 nM, n = 29). Cord [Ca²⁺] was negatively correlated with maternal systolic pressure (SBP) (r = -0.56, p < 0.01) and positively correlated with neonatal SBP (r = +0.55, p < 0.01) in the vitamin D deficient group. We conclude that low umbilical cord [vitamin D] and [Ca²⁺] may predispose mothers to higher and newborns to lower blood pressures.

Construct validity of the FOCUS© (Focus on the Outcomes of Communication Under Six): a communicative participation outcome measure for preschool children

OBJECTIVE

The aim of this study was to establish the construct validity of the Focus on the Outcomes of Communication Under Six (FOCUS©). This measure is reflective of concepts in the International Classification of Functioning Disability and Health--Children and Youth framework. It was developed to capture 'real-world' changes (e.g. communicative participation) in preschoolers' communication following speech-language intervention.

METHOD

A pre-post design was used. Fifty-two parents of 3- to 6-year-old preschoolers attending speech-language therapy were included as participants. Speech-language therapists provided individual and/or group intervention to preschoolers. Intervention targeted: articulation/phonology, voice/resonance, expressive/receptive language, play, and use of augmentative devices. Construct validity for communicative participation was assessed using pre-intervention and post-intervention parent interviews using the FOCUS© and the communication and socialization domains of the Vineland Adaptive Behavior Scales-II (VABS-II).

RESULTS

Significant associations were found between the FOCUS©, measuring communicative participation, and the VABS-II domains for: (i) pre-intervention scores in communication (r = 0.53, P < 0.001; 95% CI 0.30-0.70) and socialization (r = 0.67, P < 0.001; 95% CI 0.48-0.80); (ii) change scores over-time in communication (r = 0.45, P < 0.001; 95% CI 0.201-0.65) and socialization (r = 0.39, P = 0.002; 95% CI 0.13-0.60); and (iii) scores at post-intervention for communication (r = 0.53, P < 0.001; 95% CI 0.30-0.70) and for socialization (r = 0.37, P = 0.003; 95% CI 0.11-0.50).

CONCLUSIONS

The study provided evidence on construct validity of the FOCUS© for evaluating real-world changes in communication. We believe that the FOCUS© is a useful measure of communicative participation.

Measuring communicative participation using the FOCUS©: Focus on the Outcomes of Communication Under Six

BACKGROUND

The FOCUS© is a new outcome tool for use by both parents and clinicians that measures changes in the communicative participation skills of preschool children. Changes in communicative participation skills as measured by the FOCUS were compared across three groups of children: those with speech impairments only (SI), those with language impairments only (LI) and those with both speech and language impairments (S/LI).

METHODS

Participating families (n = 112, 75 male children) were recruited through 13 Canadian organizations. Children ranged from 10 months to 6 years 0 months (mean = 2.11 years; SD = 1.18 years) and attended speech-language intervention. Parents completed the FOCUS at the start and end of treatment. There were 23 children in the SI group, 62 children in the LI group and 27 children in the S/LI group. The average amount of the children's therapy varied from 7 to 10 h.

RESULTS

The FOCUS captures changes in communicative participation for children with a range of communication disorder types and severities. All three groups of children made clinically important improvements according to their FOCUS scores (MCID ≥ 16 points). The FOCUS captured improvements in intelligibility, independent communication, play and socialization.

CONCLUSIONS

The FOCUS measured positive changes in communicative participation skills for all three groups of children after 7-10 h of speech-language therapy. An outcome measure that targets only specific speech and language skills would miss many of the important social function changes associated with speech-language treatment.

The assessment of human erythroid output in NOD/SCID mice reconstituted with human hematopoietic stem cells

The third-generation NOD/LtSz-scid/IL2Rγ(null) (NOD/SCID IL2Rγ(null)) mouse represents a significantly improved xenograft model allowing high levels of human leukocyte engraftment over extended follow up. One remaining limitation of this mouse model, however, is the low level of circulating human erythrocytes. We established a practical ex vivo erythroid culture system of xenograft marrow progenitors to enrich for human erythroid progeny. At various time points after transplant, erythroid cells were easily assayed after 17 days of ex vivo culture of xenograft marrow, with nearly all nucleated cells of human origin and approximately 60% human GPA or CD71 positive. We then transplanted cord blood CD34(+) cells marked with a lentiviral vector encoding green fluorescent protein (GFP). Three months later, ex vivo culture of xenograft marrow progenitors showed 41.3% of the cultured erythroid cells were positive for GFP and human CD71, and 56.2% were positive for GFP and human GPA, similar to that of circulating leukocytes at the same time point. Next, G-CSF mobilized peripheral blood CD34(+) cells from a sickle cell trait subject were infused in this mouse model to determine if the hemoglobin pattern could be modeled. CD34(+) cells from the sickle cell trait subject engrafted equally compared to CD34(+) cells from normal subjects, establishing the sickle cell trait phenotype. Lastly, a comparison of adult-derived peripheral blood CD34(+) cells and cord blood-derived CD34(+) cells xenografted mice was made, and long term follow-up demonstrated a recapitulation of the fetal to adult hemoglobin switch. This approach should prove a useful tool for testing strategies for genetic manipulation of erythroid progeny and the study of hemoglobin switching.

Mass spectrometry and biochemical analysis of RNA polymerase II: targeting by protein phosphatase-1

Transcription of eukaryotic genes is regulated by phosphorylation of serine residues of heptapeptide repeats of the carboxy-terminal domain (CTD) of RNA polymerase II (RNAPII). We previously reported that protein phosphatase-1 (PP1) dephosphorylates RNAPII CTD in vitro and inhibition of nuclear PP1-blocked viral transcription. In this article, we analyzed the targeting of RNAPII by PP1 using biochemical and mass spectrometry analysis of RNAPII-associated regulatory subunits of PP1. Immunoblotting showed that PP1 co-elutes with RNAPII. Mass spectrometry approach showed the presence of U2 snRNP. Co-immunoprecipitation analysis points to NIPP1 and PNUTS as candidate regulatory subunits. Because NIPP1 was previously shown to target PP1 to U2 snRNP, we analyzed the effect of NIPP1 on RNAPII phosphorylation in cultured cells. Expression of mutant NIPP1 promoted RNAPII phosphorylation suggesting that the deregulation of cellular NIPP1/PP1 holoenzyme affects RNAPII phosphorylation and pointing to NIPP1 as a potential regulatory factor in RNAPII-mediated transcription.

Transient in vivo beta-globin production after lentiviral gene transfer to hematopoietic stem cells in the nonhuman primate

Inherited disorders of globin synthesis remain desirable targets for hematopoietic stem cell (HSC)-based therapies. Gene transfer using retroviral vectors offers an alternative to allogeneic HSC transplantation by the permanent integration of potentially therapeutic genes into primary autologous HSCs. Although proof of principle has been demonstrated in humans, this approach has been met by formidable obstacles, and large-animal models have become increasingly important for the preclinical development of gene addition strategies. Here we report lentiviral gene transfer of the human beta-globin gene under the control of the globin promoter and large fragments of the globin locus control region (LCR) in the nonhuman primate. Using an HIV-1, vesicular stomatitis virus glycoprotein G (VSV-G)-pseudotyped vector, modified to overcome a species-specific restriction to HIV-1, gene transfer to colony-forming units (CFU) derived from mobilized peripheral blood (PB) rhesus CD34+ cells was 84.4 +/- 2.33%. Erythroid cells derived from transduced rhesus CD34+ cells expressed human beta-globin at high levels as assessed by flow cytometry with a human beta-globin-specific antibody. Two rhesus macaques (RQ3586 and RQ3583) were transplanted with mobilized PB CD34+ cells transduced with our modified HIV vector at a multiplicity of infection of 80. High gene transfer rates to CFUs were achieved in vitro (RQ3586, 87.5%; RQ3583, 83.3%), with efficient human beta-globin expression among erythroid progeny generated in vitro. Early posttransplantation, gene transfer rates of 5% or higher were detectable and confirmed by genomic Southern blotting, with equivalent-level human beta-globin expression detected by flow cytometry. Long-term gene marking levels among mononuclear cells and granulocytes assessed by quantitative polymerase chain reaction gradually decreased to about 0.001% at 2 years, likely due to additional HIV-1 restrictive elements in the rhesus macaque. No evidence of clonal hematopoiesis has occurred in our animals in up to 2 years. Current efforts are aimed at developing a lentiviral vector capable of efficiently transducing both human and rhesus HSCs to allow preclinical modeling of globin gene transfer.

Long-term vector integration site analysis following retroviral mediated gene transfer to hematopoietic stem cells for the treatment of HIV infection

We previously reported the efficacy of nonmyeloablative allogeneic transplantation in 2 HIV positive recipients, one of whom received retrovirus transduced hematopoietic stem cells to confer resistance to HIV. Here we report an assessment of retroviral integration sites (RISs) recovered out to 3 years post-transplantation. We identified 213 unique RISs from the patient's peripheral blood samples by linear amplification-mediated PCR (LAM-PCR). While vector integration patterns were similar to that previously reported, only 3.76% of RISs were common among early (up to 3 months) and late samples (beyond 1 year). Additionally, common integration sites were enriched among late samples (14.9% vs. 36.8%, respectively). Three RISs were found near or within known oncogenes, but 2 were limited to early timepoints. Interestingly, an integration site near the MDS1 gene was detected in long-term follow-up samples; however, the overall contribution of MDS1 integrated clone remained stably low during follow-up.

The role of Notch3 signaling pathway in pancreatic cancer

21049

Background: Given the extremely poor prognosis of patients diagnosed with pancreatic cancer, identifying new targets for therapeutic intervention is crucial in improving clinical outcome. Existing data support a role for Notch3 pathway in human cancer, pancreas cancer in specific and in normal pancreas development. Method: We developed a pancreatic tissue array. An antibody targeting the extracellular domain of Notch3 was used to evaluate expression levels, grading from 0 to 4+ to determine the prevalence of Notch3 in pancreatic cancer. Notch3 expression was used to correlate with clinical data (IRB approved). Using small interfering RNA (siRNA) we tested the downstream effects of Notch3 in pancreatic cancer cell line BxP3 in vitro. Furthermore, to study pharmacologic inhibition of Notch3 processing and activation we exposed Panc-1, HPAF II and BxP3 pancreas cancer cell lines to γ-secretase inhibitors (previously demonstrated to block upstream of Notch3 thereby inhibiting Notch3). Results: Strong staining (+2 or greater) for Notch3 was seen in 50 of 72 (69%) resected specimens. No correlation with survival or tumor grade was seen. Using siRNA, we demonstrated that inhibiting Notch3 downregulated the antiapoptotic protein Bcl-xL but not Bcl-2. When γ-secretase inhibitors (GSI and L-685,458) were used, the previously mentioned pancreatic cell lines demonstrated reduction in proliferation rates. Conclusion: Notch3 overexpression is common in pancreas cancer. While Notch 3 expression does not clearly correlate with survival, our in vitro data suggest that Notch3 affects apoptotic pathways and may represent a potential target for intervention in patients with pancreatic cancer.

No significant financial relationships to disclose.

Dephosphorylation of CDK9 by protein phosphatase 2A and protein phosphatase-1 in Tat-activated HIV-1 transcription

Background

HIV-1 Tat protein recruits human positive transcription elongation factor P-TEFb, consisting of CDK9 and cyclin T1, to HIV-1 transactivation response (TAR) RNA. CDK9 is maintained in dephosphorylated state by TFIIH and undergo phosphorylation upon the dissociation of TFIIH. Thus, dephosphorylation of CDK9 prior to its association with HIV-1 preinitiation complex might be important for HIV-1 transcription. Others and we previously showed that protein phosphatase-2A and protein phosphatase-1 regulates HIV-1 transcription. In the present study we analyze relative contribution of PP2A and PP1 to dephosphorylation of CDK9 and to HIV-1 transcription in vitro and in vivo.

Results

In vitro, PP2A but not PP1 dephosphorylated autophosphorylated CDK9 and reduced complex formation between P-TEFb, Tat and TAR RNA. Inhibition of PP2A by okadaic acid inhibited basal as well as Tat-induced HIV-1 transcription whereas inhibition of PP1 by recombinant nuclear inhibitor of PP1 (NIPP1) inhibited only Tat-induced transcription in vitro. In cultured cells, low concentration of okadaic acid, inhibitory for PP2A, only mildly inhibited Tat-induced HIV-1 transcription. In contrast Tat-mediated HIV-1 transcription was strongly inhibited by expression of NIPP1. Okadaic acid induced phosphorylation of endogenous as well transiently expressed CDK9, but this induction was not seen in the cells expressing NIPP1. Also the okadaic acid did not induce phosphorylation of CDK9 with mutation of Thr 186 or with mutations in Ser-329, Thr-330, Thr-333, Ser-334, Ser-347, Thr-350, Ser-353, and Thr-354 residues involved in autophosphorylation of CDK9.

Conclusion

Our results indicate that although PP2A dephosphorylates autophosphorylated CDK9 in vitro, in cultured cells PP1 is likely to dephosphorylate CDK9 and contribute to the regulation of activated HIV-1 transcription.

Supra-elevated CA 19-9 in a benign hepatic cyst adenoma

BACKGROUND

Elevated CA 19-9 may be found in both cystadenomas and cystadenocarcinomas of the liver.

CASE OUTLINE

A 59-year-old woman presented with right upper quadrant abdominal pain, malaise and weight loss. Physical examination and laboratory evaluation revealed a mass in the right upper quadrant and a CA 19-9 level of 68 661 U/ml. CT scan demonstrated a cystic liver mass. She underwent a right hepatectomy, and her CA 19-9 returned to normal. Pathologic analysis revealed no malignancy.

DISCUSSION

In hepatic cystic neoplasms, an elevated CA 19-9 should not be used to establish the diagnosis of malignancy nor should it preclude resection.

Protein phosphatase-1 dephosphorylates the C-terminal domain of RNA polymerase-II

Transcription by RNA polymerase-II (RNAPII) is controlled by multisite phosphorylation of the heptapeptide repeats in the C-terminal domain (CTD) of the largest subunit. Phosphorylation of CTD is mediated by the cyclin-dependent protein kinases Cdk7 and Cdk9, whereas protein serine/threonine phosphatase FCP1 dephosphorylates CTD. We have recently reported that human immunodeficiency virus-1 (HIV-1) transcription is positively regulated by protein phosphatase-1 (PP1) and that PP1 dephosphorylates recombinant CTD. Here, we provide further evidence that PP1 can dephosphorylate RNAPII CTD. In vitro, PP1 dephosphorylated recombinant CTD as well as purified RNAPII CTD. HeLa nuclear extracts were found to contain a species of PP1 that dephosphorylates both serine 2 and serine 5 of the heptapeptide repeats. In nuclear extracts, PP1 and FCP1 contributed roughly equally to the dephosphorylation of serine 2. PP1 co-purified with RNAPII by gel filtration and associated with RNAPII on immunoaffinity columns prepared with anti-CTD antibodies. In cultured cells treated with CTD kinase inhibitors, the dephosphorylation of RNAPII on serine 2 was inhibited by 45% by preincubation with okadaic acid, which inhibits phosphatases of PPP family, including PP1 but not FCP1. Our data demonstrate that RNAPII CTD is dephosphorylated by PP1 in vitro and by PPP-type phosphatase, distinct from FCP1, in vivo.

Dysplasia as a predictive marker for invasive carcinoma in Barrett esophagus: a follow-up study based on 138 cases from a diagnostic variability study

The objective of endoscopic surveillance in Barrett esophagus (BE) is to assess the risk of subsequent development of invasive carcinoma. Criteria for morphologic evaluation of dysplasia, the presumed precursor lesion, have been established, although there are surprisingly few data in the literature correlating biopsy diagnosis of dysplasia with outcome. We collected follow-up information on 138 patients with BE whose initial endoscopic biopsy specimens had been selected for submission in an interobserver variability study performed by 12 pathologists with special interest in gastrointestinal pathology and reviewed blindly twice each by all the participants. Cases were scored as BE with no dysplasia, atypia indefinite for dysplasia (IND), low-grade dysplasia (LGD), high-grade dysplasia (HGD), intramucosal carcinoma, and frankly invasive carcinoma, thus generating 24 scores on each biopsy specimen. Clinical follow-up was obtained and correlated with both the submitting diagnoses and majority diagnoses. Kaplan-Meier statistics were used to compare both the submitting and majority diagnoses with outcome using detection or documentation of invasive carcinoma as the endpoint. Using the submitting diagnoses, no invasive carcinomas were detected in 44 cases diagnosed as BE (median follow-up, 38.5 months). Carcinomas were detected in 4 of 22 (18%) cases submitted as IND (median progression-free survival of 62 months), in 4 of 25 (15%) cases of LGD (median progression-free survival of 60 months), in 20 of 33 cases of HGD (median progression-free survival, 8 months), and all 13 (100%) cases submitted as adenocarcinoma. Grade on initial biopsy correlated significantly with progression to invasive carcinoma (log-rank P =.0001). Majority diagnosis was achieved in 99 of the cases. Using the majority diagnoses, no invasive carcinomas were found in 50 cases of BE (median follow-up, 48 months), and carcinomas were detected in 1 of 7 (14%) IND cases (80% progression-free survival at 2 months), 3 of 15 (20%) LGD (median progression-free survival, 60 months), 9 of 15 (60%) HGD (median progression-free survival, 7 months), and all 12 (100%) carcinoma. Initial grading again correlated significantly with progression to invasive carcinoma (log-rank P =.0001). However, there were 39 cases without a majority diagnosis. Among these, no carcinomas developed in 8 cases with an average score between BE and IND. Carcinomas were detected in 9 of 21 (43%) cases with an average score between IND and LGD, and 7 of 10 (70%) cases with an average score between LGD and HGD. There were ulcers in 8 of 39 cases (20%) of the "no-majority" group and in 13 of 99 (13%) of the majority cases. Of 21 total ulcerated cases, cancer was demonstrated in 15 (71%) of these on follow-up. These data support combining the IND and LGD categories for surveillance purposes. Cases without dysplasia may be followed up conservatively. The data obtained from submitted diagnoses as opposed to those from blind review suggest that knowledge of the clinical findings aids in diagnosis. The data also support the assertion that HGD is strongly associated with invasive carcinoma. Rebiopsy of ulcerated areas should be considered because they may harbor malignancy. Histologic grading of dysplasia using established criteria is a powerful prognosticator in BE. HUM PATHOL 32:379-388.

Reproducibility of the diagnosis of dysplasia in Barrett esophagus: a reaffirmation

Morphologic assessment of dysplasia in Barrett esophagus, despite limitations, remains the basis of treatment. We rigorously tested modified 1988 criteria, assessing intraobserver and interobserver reproducibility. Participants submitted slides of Barrett mucosa negative (BE) and indefinite (IND) for dysplasia, with low-grade dysplasia (LGD) and high-grade dysplasia (HGD), and with carcinoma. Two hundred fifty slides were divided into 2 groups. The first 125 slides were reviewed, without knowledge of the prior diagnoses, on 2 occasions by 12 gastrointestinal pathologists without prior discussion of criteria. Results were analyzed by kappa statistics, which correct for agreement by chance. A consensus meeting was then held, establishing, by group review of the index 125 slides, the criteria outlined herein. The second 125-slide set was then reviewed twice by each of the same 12 pathologists, and follow-up kappa statistics were calculated. When statistical analysis was performed using 2 broad diagnostic categories (BE, IND, and LG v HG and carcinoma), intraobserver agreement was near perfect both before and after the consensus meeting (mean kappa = 0.82 and 0.80). Interobserver agreement was substantial (kappa = 0.66) and improved after the consensus meeting (kappa = 0.70; P =.02). When statistical analysis was performed using 4 clinically relevant separations (BE; IND and LGD; HGD; carcinoma), mean intraobserver kappa improved from 0.64 to 0.68 (both substantial) after the consensus meeting, and mean interobserver kappa improved from 0.43 to 0.46 (both moderate agreement). When statistical analysis was performed using 4 diagnostic categories that required distinction between LGD and IND (BE; IND; LGD; HGD and carcinoma), the pre-consensus meeting mean intraobserver kappa was 0.60 (substantial agreement), improving to 0.65 after the meeting (P <.05). Interobserver agreement was poorer, with premeeting and postmeeting mean values unchanged (kappa = 0.43 at both times). Interobserver agreement was substantial for HGD/carcinoma (kappa = 0.65), moderate to substantial for BE (kappa = 0.58), fair for LGD (kappa = 0.32), and slight for IND (kappa = 0.15). The intraobserver reproducibility for the diagnosis of dysplasia in BE was substantial. Interobserver reproducibility was substantial at the ends of the spectrum (BE and HG/carcinoma) but slight for IND. Both intraobserver and interobserver variation improved overall after the application of a modified grading system developed at a consensus conference but not in separation of BE, IND, and LGD. The criteria used by the group are presented. HUM PATHOL 32:368-978.

Hepatic cryoablation-induced acute lung injury: histopathologic findings

We have previously shown that hepatic cryoablation (cryo), but not partial hepatectomy, induces a systemic inflammatory response, with distant organ injury and overproduction of NF-kappaB-dependent cytokines. Serum tumor necrosis factor-alpha (TNF-alpha) and macrophage inflammatory protein-2 (MIP-2) levels are markedly increased 1 h and beyond after cryo compared with partial hepatectomy where no elevation occurs. NF-kappaB activation (by electrophoretic mobility shift assay) is strikingly increased in the noncryo liver (but not in the lung) at 30 min and in both the liver and lung tissue 1 h after cryo, returning to the baseline by 2 h and beyond. The current study investigated the histopathologic changes associated with cryoablation-induced acute lung injury. Animals underwent 35% hepatic resection or a similar volume hepatic cryo and were sacrificed at 1, 2, 6, and 24 h. Pulmonary histologic features were assessed using hematoxylin and eosin and immunoperoxidase staining with a macrophage-specific antibody (anti-lysozyme, 1:200 dilution, Dako, Carpinteria, CA). The following features were graded semiquantitatively (0-3): perivascular lymphoid cuffs, airspace edema and hemorrhage, margination of neutrophils within pulmonary vasculature, and the presence of macrophages with foamy cytoplasm in the pulmonary interstitium. Hepatic resection (n = 21) resulted in slight perivascular edema at 1, 2, 6, and 24 h post-resection, but there were no other significant changes. Pulmonary findings after hepatic cryo (n = 22) included prominent perivascular lymphoid cuffs 1 and 2 h following hepatic injury that were not present at any other time point (P 0.01). Marginating PMNs and foamy macrophages were more common after cryo at all time points (P<0.05, cryo vs resection). Severe lung injury, as evidenced by airspace edema and parenchymal hemorrhage, was present in four of six (67%) animals at 24 h (P 0.03). In follow-up studies immediate resection (n = 15) of the cryo-treated liver prior to thawing prevented the pulmonary changes. The findings of pulmonary perivascular interstitial macrophages 2 h following hepatic cryo suggests that hepatic cytokine production may induce downstream recruitment of pulmonary macrophages, which may contribute to subsequent severe lung injury. This study suggests that a soluble mediator from direct liver injury leads to neutrophilic lung inflammation and this is associated with the thawing phase of cryoablation.

Contemporary trends and practice strategies in pediatric occupational and physical therapy

This paper identifies and reflects on recent trends in pediatric occupational therapy and physical therapy practice. These trends were initially identified by the student authors for a Maternal and Child Health (MCH) leadership seminar, which was conducted as part of the postprofessional graduate program in physical therapy at the University of Washington. Trends were then reviewed and discussed among the student and faculty authors. Consensus was reached on the most important trends, which were subsequently summarized in this paper. The first part of the paper reviews the impact of these trends on current and future clinical practices in health, educational, and community-based settings. The second part of the paper offers proposed directions to meet the challenges presented by the trends in four key areas; (1) research, (2) professional education, (3) enhancing family-centered care, and (4) advocacy.

Targeted disruption of the Kvlqt1 gene causes deafness and gastric hyperplasia in mice

The KvLQT1 gene encodes a voltage-gated potassium channel. Mutations in KvLQT1 underlie the dominantly transmitted Ward-Romano long QT syndrome, which causes cardiac arrhythmia, and the recessively transmitted Jervell and Lange-Nielsen syndrome, which causes both cardiac arrhythmia and congenital deafness. KvLQT1 is also disrupted by balanced germline chromosomal rearrangements in patients with Beckwith-Wiedemann syndrome (BWS), which causes prenatal overgrowth and cancer. Because of the diverse human disorders and organ systems affected by this gene, we developed an animal model by inactivating the murine Kvlqt1. No electrocardiographic abnormalities were observed. However, homozygous mice exhibited complete deafness, as well as circular movement and repetitive falling, suggesting imbalance. Histochemical study revealed severe anatomic disruption of the cochlear and vestibular end organs, suggesting that Kvlqt1 is essential for normal development of the inner ear. Surprisingly, homozygous mice also displayed threefold enlargement by weight of the stomach resulting from mucous neck cell hyperplasia. Finally, there were no features of BWS, suggesting that Kvlqt1 is not responsible for BWS.

Hepatic stellate cell activation in nonalcoholic steatohepatitis and fatty liver

Factors associated with the development of fibrosis in nonalcoholic steatohepatitis (NASH) are largely unknown, although an association with increased hepatic iron has been suggested. Hepatic stellate cells are the principal collagen-producing cells in many liver diseases and when activated express alpha-smooth muscle actin (alpha-SMA). Hepatic stellate cell activation and association with fibrosis, necroinflammatory activity, steatosis, and stainable iron in 60 cases of NASH and 16 cases of steatosis were evaluated. All 76 patients were obese or had other risk factors for NASH. All biopsy specimens were stained for alpha-smooth muscle actin to evaluate the pattern of hepatic stellate cell activation and were evaluated for inflammatory activity (0 to 3), fibrosis (0 to 4), and stainable iron stores (0 to 4). The zonal location of activated stellate cells was recorded, and the degree of activation was graded as high-grade or low-grade based on the percentage of lobular alpha-SMA+ cells. Activated stellate cells were identified in the hepatic lobule in 74 of 76 biopsy specimens and graded as low-grade in 26 and high-grade in 48. Zone 3 was involved in 72 of 74 positive cases, and in 33 cases, the activated stellate cells were preferentially located in zone 3. The degree of stellate cell activation correlated with fibrosis but not with inflammatory activity, severity of steatosis, or stainable iron. In most cases, the degree of stellate cell activation paralleled the degree of hepatic fibrosis, but in 25 cases, the degree of hepatic stellate cell activation was greater than expected, raising the question of whether such patients are at risk for disease progression.

Prevalence and prognostic significance of neuroendocrine cells in esophageal adenocarcinoma

Neuroendocrine differentiation is common in adenocarcinomas of the stomach and colon and may be associated with a slightly better prognosis in gastric adenocarcinoma. We studied neuroendocrine differentiation in esophageal adenocarcinomas and associated Barrett's esophagus (BE) to determine association with patient outcome. Fifty-eight cases of esophageal adenocarcinoma (15 biopsies, 43 resections) from 52 patients were stained with a monoclonal antibody to chromogranin (CG). Medical records were reviewed for tumor stage, response to therapy, and patient survival. Thirty-two patients received radiation and chemotherapy, and four received radiation. Twelve of 58 (20.7%) esophageal adenocarcinomas contained scattered CG-positive cells. Tumors with CG-positive cells were moderately to poorly differentiated, and many consisted of large cribriform glands, similar to intestinal-type adenocarcinomas. One case of small cell carcinoma of the esophagus was weakly CG positive; another was negative. Neuroendocrine differentiation was retained in lymph node metastases in two cases but lost in three other cases. In 10 CG-negative primary tumors, lymph node metastases were also negative. For five of six patients with paired biopsy/resection specimens, no CG-positive cells were seen in either specimen; one patient had CG-positive cells only in the resection. There was no difference in tumor stage at surgery or survival time between CG-positive and CG-negative tumors. BE was present in 34 cases and contained CG-positive cells in 21 of 34 (61.8%). Low-grade dysplasia contained CG-positive cells in 11 of 14 cases (78.6%) and high-grade dysplasia in 3 of 6 cases. Fourteen of 21 (66.7%) adenocarcinomas associated with CG-positive BE were negative for CG. In summary, neuroendocrine differentiation is common in BE and is retained in low- and high-grade dysplasia but is usually lost in esophageal adenocarcinoma. The presence of scattered neuroendocrine cells does not affect patient outcome.

Acute lung injury after hepatic cryoablation: correlation with NF-kappa B activation and cytokine production

BACKGROUND

Previous clinical reports have documented multisystem organ injury after hepatic cryoablation. We hypothesized that hepatic cryosurgery, but not partial hepatectomy, induces a systemic inflammatory response characterized by distant organ injury and overproduction of nuclear factor kappa B (NF-kappa B)-dependent, proinflammatory cytokines.

METHODS

In this study, rats underwent either cryoablation of 35% of liver parenchyma or a similar resection of left hepatic tissue. Serum tumor necrosis factor-alpha and macrophage inflammatory protein-2 levels and NF-kappa B activation were assessed by electrophoretic mobility shift assay at 30 minutes 1, 2, 6, and 24 hours after either procedure.

RESULTS

Cryoablation of 35% of liver (n = 22 rats) resulted in lung injury and a 45% mortality rate within 24 hours of surgery, whereas 7% treated with 35% hepatectomy (n = 15 rats) died during the 24 hours after surgery (P < .05, cryoablation vs hepatectomy). Serum tumor necrosis factor-alpha and macrophage inflammatory protein-2 levels were markedly increased in rats (n = 10 rats) 1 hour after hepatic cryoablation compared with rats that underwent partial hepatectomy (P < .005). We evaluated NF-kappa B activation by electrophoretic mobility shift assay in nuclear extracts of liver and lung after cryosurgery and found that NF-kappa B activation was strikingly increased in the liver but not the lung at 30 minutes and in both organs 1 hour after cryosurgery, and returned to baseline in both organs by 2 hours. In rats undergoing 35% hepatectomy, no increase in NF-kappa B activation was detected in nuclear extracts of either liver or lung at any time point.

CONCLUSIONS

These data show that hepatic cryosurgery results in systemic inflammation with activation of NF-kappa B and increased production of NF-kappa B-dependent cytokines. Our data suggest that lung injury and death in this animal model is mediated by an exaggerated inflammatory response to cryosurgery.

Concurrent paclitaxel and thoracic irradiation for locally advanced esophageal cancer

Esophageal cancer is a major cause of morbidity and mortality worldwide. Although patients often present with apparently resectable disease, systemic spread frequently occurs before the development of symptoms and detection of tumor. The use of combined chemoradiation therapy, particularly before resection, appears to prolong survival and increase cure rates in certain histologic subtypes. Four randomized phase III trials compared preoperative chemoradiotherapy plus surgery with surgery alone. In trials including only patients with squamous histology, no improvement in survival was observed with preoperative chemoradiation therapy; however, in a trial including only patients with adenocarcinoma histology, improved median and overall survival were observed. Paclitaxel has been evaluated as a single agent in a phase II trial in previously untreated patients with locally advanced unresectable or metastatic esophageal cancer; the overall response rate was 32% and median survival was 13.2 months. Paclitaxel-based combinations also have been evaluated in esophageal cancer; particularly encouraging preliminary results have been achieved with paclitaxel/cisplatin/5-fluorouracil. Because paclitaxel is a potent radiosensitizer, it also has been evaluated in combination with radiation therapy for esophageal and other thoracic cancers, alone and in combination with other chemotherapeutic agents. Preliminary results suggest that neoadjuvant therapy with paclitaxel-based combinations (including 5-fluorouracil and cisplatin) and radiation is highly active, with variable toxicity. A goal of future trials is to assess paclitaxel-based combined modality therapy in combination with other new chemotherapeutic agents.

Ki-1+ large-cell anaplastic lymphoma after Ewing sarcoma

PURPOSE

A large cell anaplastic lymphoma that developed after treatment of a Ewing sarcoma (ES) is described.

PATIENT

An 11-year-old girl with a pelvic ES developed a large cell, Ki-1+, anaplastic lymphoma in the same anatomic location 10 months after multimodal therapy.

RESULTS

ES recurred in the primary site 16 months after allogeneic marrow transplantation and 3.5 years after initial diagnosis, but the patient remains in remission from her lymphoma.

CONCLUSION

The occurrence of lymphoma and ES in a short time interval in the same patient is very unusual. Whether etiologic factors other than chemoradiotherapy, including genetic disposition, play a role remains to be elucidated.

Liver regeneration is transiently impaired in urokinase-deficient mice

To test the hypothesis that urokinase-type plasminogen activator (uPA) plays an important role in liver regeneration in vivo, partial hepatectomy was performed on wild-type and uPA-deficient (uPA-/-) mice. Mice were studied at 24, 44, and 96 h and at 8 days and 4 wk post-partial hepatectomy for evidence of regeneration, as measured by mitotic indexes and [3H]thymidine incorporation. In wild-type mice, thymidine incorporation peaked at 44 h and this index was reduced by 47% in uPA-/- mice (P = 0.02). By 8 days, however, liver mass was comparable in both groups. Histological analysis revealed the presence of focal areas of fibrin deposition and cellular loss by 24 h that were more severe and prevalent in uPA-/- mice than in wild-type mice (62 and 23%, respectively; chi2 = 3.939, P = 0.047). In contrast, regeneration was not impaired in uPA receptor (uPAR)-deficient mice at 24 and 44 h. Taken together, these data indicate that uPA, independent of its interaction with the uPAR, plays an important role in liver regeneration in vivo.

Expression of beta-catenin, alpha-catenin, and E-cadherin in Barrett's esophagus and esophageal adenocarcinomas

Loss of expression and function of the E-cadherin/catenin membrane complex can result in loss of cell adhesion and contribute to invasive or metastatic potential in carcinomas. The aim of this study was to examine the expression of alpha- and beta-catenin and E-cadherin in Barrett's esophagus with and without dysplasia and in esophageal adenocarcinomas and to identify any relationship with tumor growth pattern and clinical outcome. Immunoperoxidase staining for alpha- and beta-catenin and E-cadherin was performed on specimens of Barrett's esophagus with and without dysplasia and on 54 esophageal adenocarcinoma specimens. Membranous staining for all of the components was seen in normal gastric and esophageal mucosa. Abnormal expression of beta-catenin, alpha-catenin, and E-cadherin was significantly associated with higher degrees of dysplasia in Barrett's esophagus. Fourteen of 16 cases of high grade dysplasia and 7 of 7 cases of intramucosal carcinoma showed abnormal expression of beta-catenin, compared with 3 of 6 cases indefinite for dysplasia and 11 of 17 cases with low grade dysplasia (P = 0.022). Similar results were seen for expression of alpha-catenin (P < .01) and E-cadherin (P = .049). In esophageal adenocarcinomas, preserved expression of these proteins occurred more frequently in well-differentiated tumors; abnormal expression was more common in diffusely infiltrative poorly differentiated tumors that did not form glands. Focal nuclear staining for beta-catenin was present in two high-grade dysplasias, two intramucosal carcinomas, and five adenocarcinomas. No survival advantage was demonstrated for patients whose tumors retained expression of these cell adhesion components. In conclusion, abnormal expression of the E-cadherin/catenin membrane complex is common in esophageal adenocarcinoma and occurs early in the dysplasia/carcinoma sequence in Barrett's esophagus, indicating that disturbances in this cell adhesion complex might be important in tumorigenesis and tumor progression in this disorder.

Alterations in colonic mucosal vessels in patients with cirrhosis and noncirrhotic portal hypertension

Changes in intestinal mucosal microvasculature as a cause of lower gastrointestinal hemorrhage in patients with portal hypertension have been well documented clinically, but the analogous histomorphological changes have not been well characterized. The goal of this study was to evaluate qualitative and quantitative changes in colonic mucosal vessels in patients with cirrhosis or clinically evident portal hypertension and to correlate these changes with endoscopic and clinical findings. Colon biopsy or resection specimen slides from 46 patients with biopsy-proven cirrhosis (44 patients) or noncirrhotic portal hypertension (two patients) were reviewed. Immunoperoxidase stain for CD34 antigen was used to facilitate visualization of mucosal vessels, and vessel diameter was measured with a micrometer. Patients with inflammatory bowel disease were excluded. Twenty-four normal colon biopsy specimens served as controls. Mucosal vessels were divided into superficial, intermediate, and deep layers. As a group, the cirrhotic patients had a significantly higher mean diameter of vessels in all three layers. Qualitatively, increased numbers of small vessels and prominent branching were noted, especially in the superficial and intermediate layers. Tortuous, thick-walled vessels, suggesting arterialization of venules, were present in some cases. Eleven patients had endoscopic findings suggestive of vascular abnormalities, including erythematous mucosal patches, red macules, and telangiectasias. Eighteen had esophageal varices, and five had portal gastropathy. Nineteen patients had gastrointestinal (GI) bleeding, localized to the lower GI tract in 11. These qualitative and quantitative findings suggest that colonic mucosal vascular lesions are common in portal hypertension and may represent a potential source of clinically significant lower GI hemorrhage in these patients.

Can experimental models of rodent implantation glioma be improved? A study of pure and mixed glioma cell line tumours

To evaluate the hypothesis that co-implantation of different rodent glioma cell lines might result in experimental brain tumours that more closely resemble human gliomas the neuropathology and immunocytochemical features of implantation gliomas derived from single cell lines (C6, A15A5, F98), two cell lines admixed 50:50 prior to implantation (C6 + F98 and C6 + A15A5) and three cell lines equally admixed (C6 + A15A5 + F98) was studied in the adult Wistar rat. Tumours grew consistently following implantation of the single and the two admixed cell lines, however tumour growth following triple mix implantation was considerably and consistently impaired. The tumours derived from admixed cell lines showed regional heterogeneity with areas characteristic of both the primary cell lines. Foci of lymphocytic infiltrates, tumoural necrosis, often with pseudopallisading, and peritumoural edema were consistent features of all tumours. Limited parenchymal and more extensive perivascular tumoural invasion was seen predominantly in tumours containing the C6 cell line. There were no significant differences in GFAP, vimentin and HSP70 staining between the mixed tumours, although the pure F98 and A15A5 tumours were, unlike the pure C6 gliomas, S-100 negative. Using PCNA expression as a measure of the tumour proliferation all except the tumours derived from the three cell lines mix, which had a staining index of 7-10%, had focal staining indices in viable tumour of between 40-80%. There was focal positive staining in both perilesional brain and in regions of all tumours for the macrophage markers ED-1 and ED-2. None of the three cell lines stained in vitro for either ED1 and ED2 but all were constitutively positive in vitro for OX-6, a proposed marker for antigen presenting cells. The macrophage and lymphocytic response suggest a vigorous but largely ineffective immunological response had been mounted against all tumours. The consistent failure of the triple mix tumours to grow is unexplained. This work has shown the feasibility of producing 'mixed' cell line experimental gliomas by combining two cell lines at the time of innoculation. However, the relative failure to produce (i) mixed tumours that have properties not inherent to either parent cell line and (ii) implantation glioma with three cell lines suggest there are limits to this approach. Admixture of cell lines at the time of implantation therefore does not make experimental glioma models that more closely resemble natural gliomas, and also has some particular disadvantages. This experimental approach is therefore not recommended for use in the study of tumour biology and in evaluating the effectiveness of novel therapies.

Functional studies on the anti-pathoangiogenic properties of CM101

Group B streptococcus (GBS) isolated from human neonates diagnosed with sepsis and respiratory distress produces a polysaccharide exotoxin (CM101) which has been previously described as GBS toxin. CM101 infused i.v. into tumor-bearing mice causes rapid tumor neovascularitis, infiltration of inflammatory cells, inhibition of tumor growth and tumor apoptosis. CM101 has successfully completed phase I studies in refractory cancer patients with very encouraging results. We have now demonstrated a mechanism of action for CM101. Using a normal mouse tumor model, we have examined tumor and normal tissues which were harvested at 0, 5, 15, 30 and 60min post-infusion of either CM101 or dextran. We present evidence that CM101 is rapidly (within the first 5min) bound to the tumor neovasculature. Complement is activated by the alternative pathway (C3) and leukocytes start to infiltrate the tumor within the first 5min. Through RT-PCR and immunohistochemical techniques, we demonstrate that proinflammatory cytokines, interleukin-6 and tumor necrosis factor (TNF)-alpha, are up-regulated in infiltrating leukocytes and TNF receptor 2 is up- regulated in the targeted tumor neovasculature. Combined, these events constitute possible explanations for the observed pathophysiology of tumor ablation.

RT in situ PCR for the detection of mRNA transcripts of Fas-L in the immune-privileged placental environment

Rapid and reproducible detection of RNA in cells and tissue sections is routinely accomplished using in-situ hybridization technique provided that the target number of mRNA copies is above a minimum number. Detection of low copy transcripts is problematic when threshold detection occurs below clear signal resolution or alternatively, when technical problems result in background noise which occludes clear signal. RT in-situ PCR methodology utilizes both the power and specificity of PCR to amplify target whose localization is subsequently detected at the cellular level. RT in-situ PCR methods routinely involve a two-step methodology. mRNA copies are initially transcribed into cDNA. This step is followed by a separate PCR step wherein amplification of the newly synthesized cDNA takes place. A simplified one-step procedure biochemically compartmentalizes these sequential steps within a single applications methodology using the enzyme rTth. This method was successfully applied to detect and localize mRNA transcripts for Fas ligand within the immune privileged placental environment and to provide verification of immunohistochemical localization of gene product.

Gastric graft-versus-host disease: a blinded histologic study

Acute graft-versus-host disease (GvHD) of the upper gastrointestinal (GI) tract is common after allogeneic bone marrow transplantation (BMT). However, diagnosis cannot be made on clinical presentation and endoscopic findings alone, because these are nonspecific, and histologic confirmation is often desirable. The diagnosis of gastric GvHD is often based on subtle findings with considerable potential for variability in interpretation. Evaluation of the reproducibility of diagnosis and recognition of histologic features of gastric GvHD was based on blinded review of 56 gastric biopsies (24 from patients with allogeneic BMT or unrelated umbilical cord blood transplantation and 32 control biopsies from patients who did not undergo BMT, of whom eight had active GI cytomegalovirus [CMV] infection). Histologic criteria for GvHD were apoptosis and gland destruction, sparse inflammatory infiltrate, and granular eosinophilic debris in dilated glands. Seventeen patients (22 biopsies) were judged to have clinical GvHD on the basis of skin or liver involvement and GI symptoms without other known cause. Eighteen of these 22 gastric biopsies were classified as GvHD by at least two of the three pathologists on initial review. Blinded histologic diagnosis of GvHD had a positive predictive value of 69%, a sensitivity of 82%, and specificity of 76%. False-positive results occurred in CMV gastritis, human immunodeficiency virus (HIV) infection, primary immunodeficiency, and after renal transplantation. Of individual features, granular debris in glands was a specific (94% specificity), but insensitive (41% sensitivity) marker for GvHD. Distinction between GvHD and CMV infection can be difficult, and GvHD can be confused with changes seen in HIV infection and other immunodeficiency states.

Peribiliary vascular plexus in primary sclerosing cholangitis and primary biliary cirrhosis

The peribiliary vascular plexus plays an important role in physiology of bile flow. Disturbance of the microcirculation may contribute to ductal injury, but little is known about alterations in the vascular supply of small bile ducts in liver disease. Immunoperoxidase stains for vascular endothelium (Ulex europaeus, factor VIII-related antigen, CD34) were used to study the peribiliary vascular plexus in 20 cases of primary sclerosing cholangitis (PSC) and 27 cases of primary biliary cirrhosis (PBC), two diseases characterized by bile duct destruction. Normal liver from 10 autopsy cases of sudden cardiac death was used as a control. Interlobular bile ducts (20- to 80-microm diameter) were identified on AE1/AE3 immunostain; vessels adjacent to the basement membrane of these ducts were counted. Normal interlobular bile ducts had an average of 2.15 vessels per duct (range, 1.68 to 2.71). Few PBC or PSC cases had a normal number of peribiliary vessels. There was a trend toward vasopenia at higher stage, although vascular loss was noted in early stages as well. The pattern of vascular loss was different for the two diseases; in PSC, the periductal capillaries were often preserved but were pushed away from the basement membrane by concentric deposits of collagen. Small residual vessels could be identified within fibrous scars of obliterated bile ducts in PSC. In 4 stage 3 or 4 PSC cases with little bile duct injury, vessel/duct ratio approached normal levels. In PBC, vessels were obliterated in areas of granulomatous inflammation and heavy lymphocytic infiltrate around bile ducts. In conclusion, loss of peribiliary vessels is common in PSC and PBC. Vessel loss is seen in early stages and may contribute an element of ischemia to continued small bile duct loss but is probably secondary to the inflammatory process.

Expression of cell adhesion molecule CD44 in primary tumors of the liver: an immunohistochemical study

CD44, a widely distributed integral membrane protein, has been implicated in tumor invasion and metastatic spread in some human carcinomas and lymphomas. In this study, 35 cases of hepatocellular carcinoma from 32 patients (11 cholangiocarcinomas, 9 hepatic adenomas, and 5 cases of focal nodular hyperplasia, a non-neoplastic lesion) were examined by immunohistochemical methods for expression of CD44. The mouse monoclonal antibody A3D8 was used on formalin-fixed, paraffin-embedded tissue; this antibody does not distinguish between standard CD44 and splice variants. Positive membrane staining was seen in 13 of 35 cases of hepatocellular carcinoma (12 of 32 patients), 8 of 11 cases of cholangiocarcinoma, and 1 of 9 cases of hepatic adenoma. The strongest staining for CD44 was seen in two cases of fibrolamellar carcinoma, but CD44 expression was otherwise not related to degree of tumor differentiation. All five cases of focal nodular hyperplasia were negative for CD44. In non-neoplastic liver, hepatocytes were negative; sinusoidal lining cells and portal lymphocytes were positive; bile ducts and proliferating bile ductules were focally positive in some cases. Anatomic stage at time of presentation was similar in both groups of patients, with most patients presenting with stage III or IV disease. A trend towards slightly longer survival in patients whose hepatocellular carcinomas were CD44 negative was noted. These results show that aberrant CD44 expression is present in a subset of hepatocellular carcinomas and in most cholangio-carcinomas. The relationship between CD44 expression and tumor spread is unclear in this group of tumors, but is unlikely to be a simple association between CD44 expression and metastatic potential.

Endoscopic tattoo agents in the colon. Tissue responses and clinical implications

Laparoscopic surgery frequently requires tattooing of endoscopically identified sites for localization during surgery. Some tattooing agents cause serious tissue injury, which must be recognized in pathologic examination. Seven surgically resected colons were reviewed after injection with methylene blue or India ink at intervals of 1 day to 7 weeks before surgery. Early reactions to India ink included necrosis, edema, and neutrophilic infiltration in the submucosa and muscularis propria. Vessels were inflamed but without fibrinoid necrosis. Early reactions to methylene blue included ischemic ulceration, necrosis, and eosinophilic infiltration in the submucosa as well as fibrinoid necrosis of vessel walls. In the repair of methylene-blue injury, obliterative intimal fibrosis was seen in vessels. Such changes were absent in the colons injected with India ink. The India ink remained remained visible with the naked eye and microscopically 7 weeks after injection. Methylene blue was not grossly visible 7 days after injection, and only microscopic particles of pigment remained in widely scattered macrophages. In light of these findings, the amount of ink injected should be minimized and the injection site should be completely resected at surgery. Methylene blue is a poor tattoo agent, but its occasional use continues, and pathologists should recognize the resulting reaction.

Gastrointestinal pathology in patients with common variable immunodeficiency and X-linked agammaglobulinemia

Review of the medical records of 43 patients with common variable immunodeficiency (CVID) and 23 patients with X-linked agammaglobulinemia (XLAG) revealed a high incidence of chronic gastrointestinal complaints, most commonly diarrhea. Thirty-eight biopsies, four small-bowel resection specimens, and one autopsy from 10 patients with CVID and one patient with XLAG showed a wide range of abnormalities. A pattern resembling acute graft-versus-host disease, with apoptotic bodies and lymphocytes in crypts, was seen in the stomach (four patients), small bowel (three patients), and colon (three patients). Small-bowel specimens from three CVID patients with malabsorption showed mild to severe villous atrophy. Three CVID patients had Giardia in biopsies. Two cases of small bowel lymphoma associated with nodular lymphoid hyperplasia were identified in CVID patients. One patient's small bowel contained foamy histiocytes in the lamina propria, resembling Whipple's disease or chronic granulomatous disease, with numerous apoptotic bodies in crypts. Ultrastructurally, the histiocytes contained cellular debris. The patient with XLAG had recurrent fissuring necrosis of small bowel resembling Crohn's disease; a patient with CVID had colitis with features similar to ulcerative colitis. Poorly formed granulomas were seen in the stomach (one CVID patient) and the colon (two CVID patients). Lymphocyte populations were dominated by T cells; B cells were scarce except in lymphoid follicles in CVID patients with nodular lymphoid hyperplasia. Patients with CVID and XLAG manifest a spectrum of abnormalities in the gastrointestinal tract, with patterns superficially resembling graft-versus-host disease, inflammatory bowel disease, and Whipple's disease, but often lacking some of the diagnostic features of the diseases. Many of the CVID patients with chronic gastrointestinal complaints (62%) also had evidence of autoimmune phenomena, suggesting that in some patients the inflammatory process in the gastrointestinal tract has an autoimmune component.

Expression of p53 in adenocarcinoma of the gallbladder and bile ducts

Point mutation of the p53 tumor suppressor gene appears to be an important event in tumor development and progression, and overexpression of the p53 gene product has been widely studied in a variety of neoplasms. Some point mutations of the p53 gene lead to an increase in half-life in the gene product, which accumulates in the nucleus and can be detected by immunohistochemical means. We studied overexpression of p53 protein in specimens from 12 patients with adenocarcinoma of the gallbladder, two gallbladders with epithelial dysplasia without carcinoma, eight carcinomas of the common bile duct, 13 hilar cholangiocarcinomas, and six peripheral cholangiocarcinomas. The monoclonal antibody Ab-2 (Oncogene Science) was used in conjunction with citrate microwave antigen retrieval. Nuclear staining was scored as positive (graded 1 to 3, depending on number of positive nuclei) or negative. Overexpression of p53 protein was present in 7/12 (58%) gallbladder carcinomas, and was seen more often in moderately or poorly differentiated tumors. Intramucosal carcinoma adjacent to invasive carcinoma was positive in three cases, although fewer cells stained than in the carcinoma. Two cases of low-grade dysplasia not associated with carcinoma were negative. Expression of p53 was not an independent prognostic factor when survival was related to grade and stage of tumor. Three of eight (38%) common bile duct carcinomas and 5/13 (38%) hilar cholangiocarcinomas were positive for p53. Slightly fewer (2/6, 33%) peripheral cholangiocarcinomas were positive. No difference in survival relative to p53 expression was demonstrated.