Transcriptional subtyping and CD8 immunohistochemistry identifies poor prognosis stage II/III colorectal cancer patients who benefit from adjuvant chemotherapy

Purpose

Transcriptomic profiling of colorectal cancer (CRC) has led to the identification of four consensus molecular subtypes (CMS1 to 4) that have prognostic value in stage II and III disease. More recently, the Colorectal Cancer Intrinsic Subtypes (CRIS) classification system has helped to define the biology specific to the epithelial component of colorectal tumors; however, the clinical value of these classification systems in the prediction of response to standard-of-care adjuvant chemotherapy remains unknown.

Patients and Methods

Using samples from four European sites, we assembled a novel cohort of patients with stage II and III CRC (n = 156 samples) and performed transcriptomic profiling and targeted sequencing and generated a tissue microarray to enable integrated multiomics analyses. We also accessed data from two published cohorts of patients with stage II and III CRC: GSE39582 and GSE14333 (n = 479 and n = 185 samples, respectively).

Results

The epithelial-rich CMS2 subtype of CRC benefitted significantly from treatment with adjuvant chemotherapy in both stage II and III disease (P = .02 and P < .001, respectively), whereas the CMS3 subtype significantly benefitted in stage III only (P = .001). After CRIS substratification of CMS2, we observed that only the CRIS-C subtype significantly benefitted from treatment with adjuvant chemotherapy in stage II and III disease (P = .0081 and P < .001, respectively), whereas the CRIS-D subtype significantly benefitted in stage III only (P = .0034). We also observed that CRIS-C patients with low levels of CD8⁺ tumor-infiltrating lymphocytes were most at risk for relapse in both stage II and III disease (log-rank P = .0031; hazard ratio, 12.18 [95% CI, 1.51 to 98.58]).

Conclusion

Patient stratification using a combination of transcriptional subtyping and CD8 immunohistochemistry analyses is capable of identifying patients with poor prognostic stage II and III disease who benefit from adjuvant standard-of-care chemotherapy. These findings are particularly relevant for patients with stage II disease, where the overall benefit of adjuvant chemotherapy is marginal.

Abstract LB-054: FKBPL as a novel therapeutic target and prognostic biomarker in high grade serous ovarian cancer

FKBPL is a secreted protein with well-established anti-angiogenic and anti-cancer stem cell activity. A novel therapeutic peptide, ALM201, derived from this protein has successfully completed a phase I clinical trial and was granted orphan drug status, by the FDA, for the treatment of ovarian cancer. Ovarian cancer is the most lethal gynecological cancer and there are no prognostic biomarkers currently used in the clinic. It is associated with a high incidence of recurrent chemo-resistant disease and this has been attributed to a treatment-resistant subpopulation of CD44+ cancer stem cells (CSCs). Previously, we presented evidence that CD44 is a potential target of ALM201 and here, for the first time, we investigate its ability to target both angiogenesis and CSCs in HGSOC. Tumorsphere and flow cytometry assays demonstrated that ALM201 is effective at reducing CSCs in a range of HGSOC cell lines and primary patient samples in vitro. Clonogenic assays demonstrated that ALM201 is not cytotoxic, but rather mediates ovarian CSC differentiation. In vitro, ALM201 displayed potent anti-CSC activity in the HGSOC cell line, OVCAR3. However, OVCAR3 tumor xenografts are not dependent on angiogenesis for their growth and therefore ALM201 did not elicit a strong response in this model. Furthermore, OVCAR3 xenografts dramatically upregulated the inflammatory cytokines IL-6 and IL-8, which is consistent with the lack of anti-CSC activity of ALM201 in vivo compared to in vitro. In contrast, treatment of highly angiogenic Kuramochi tumor xenografts, another HGSOC cell line, resulted in a statistically significant delay in both tumor growth and tumor initiation. This was associated with disruption of the CD31+ vascular network and a 10 fold decrease in the CSC population. Finally, using HGSOC tissue microarrays we demonstrated that high endogenous expression of FKBPL correlated with increased progression free interval; indicating the potential for FKBPL to be used as a prognostic biomarker in HGSOC. HGSOC cell lines display marked differences in tumor vascularisation in vivo. ALM201, a peptide fragment of FKBPL, has potent anti-CSC and anti-angiogenic activity in an HGSOC xenograft which is dependent on angiogenesis for growth; an important finding for the clinical development of ALM201. Our data also strongly suggest that FKBPL is a potential novel prognostic biomarker in HGSOC, supporting its endogenous anti-tumor activity.

Citation Format: Stephanie Annett, Gillian Moore, Amy Short, Neermeen Moustafa, Sudipto Das, Darran O'Connor, Cian McCrudden, Adrien Kissenpfenning, Laura Nelson, Ian Harley, Ken Arthur, Anita Yakkundi, Glen McCluggage, Andrea Marshall, Fiona Furlong, Helen O. McCarthy, Graham Cotton, Timothy Harrison, Lana McClements, Tracy Robson. FKBPL as a novel therapeutic target and prognostic biomarker in high grade serous ovarian cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr LB-054.

PD-L1 expression and response to neo-adjuvant chemotherapy in esophageal adenocarcinoma

4023

Background: Programmed Death-1 Receptor (PD-1) and its ligand (PD-L1) downregulate T cell activation and suppress tumor killing. This study investigated the role of PD-L1 and tumor infiltrating lymphocytes (TILs) in response to neo-adjuvant therapy and prognosis in esophageal adenocarcinoma (EAC). Methods: Transcriptional profiling of 273 formalin fixed paraffin embedded pre-treatment endoscopic EAC biopsies was carried out using the Almac Diagnostics Xcel array and the expression levels of PD-L1 probesets corresponding to protein encoding extracted. Response was assessed by tumor regression grade (TRG; score ≤ 2 = response). Immunohistochemistry (IHC) for PD-L1 and CD8 was performed in matched resection specimens from 135 patients. All EAC patients were treated with cisplatin-based neo-adjuvant chemotherapy followed by surgical resection between 2003 and 2014 at four UK centers as part of the OCCAMS consortium. Associations between expression, protein levels and TRG were assessed by Kruskal-Wallis, Mann-Whitney Unpaired, Spearman rank correlation or chi-squared tests. Survival analysis was performed using Cox Proportional Hazards regression. Results: High PD-L1 gene expression in the pre-chemotherapy biopsies was associated with pathological response (TRG ≤ 2; p = 0.02) following neo-adjuvant chemotherapy. PD-L1 ( > 5%) was expressed in the tumor or stromal cells in 4% and 15% of resection specimens respectively. PD-L1 gene and IHC expression ( > 5%) were closely associated between the biopsies and both the tumor (p = 0.032) and stroma (p = 0.019) of the matched resection specimens. Patients with PD-L1 IHC positivity in tumor cells demonstrated improved relapse-free survival (HR 0.314; 95% CI 0.099-0.997; p = 0.049) and positive stromal PD-L1 IHC staining correlated with pathological response (p = 0.05). Biopsy gene expression of PD-L1 and CD8 was closely associated (p = 0.024) and the presence of CD8+ TILs in the microenvironment strongly correlated with tumor (p < 0.001) and stromal (p < 0.001) PD-L1 positivity. Conclusions: High PD-L1 expression in the pre-treatment biopsies in EAC is predictive of response to neo-adjuvant chemotherapy and may aid selection of conventional and immune-targeted agents.

Association of a DNA damage response deficiency (DDRD) assay with prognosis in resected esophageal and gastric adenocarcinoma

4026

Background: Current strategies to guide the selection of neo-adjuvant or adjuvant therapy in esophageal and gastric adenocarcinomas (EAC/GAC) are inadequate. We assessed a clinically validated 44 gene DNA Damage Response Deficiency (DDRD) assay to predict prognosis following neo-adjuvant DNA damaging chemotherapy (CT) in EAC and adjuvant CT or chemo-radiotherapy (CRT) in GAC. Methods: Transcriptional profiling of 273 formalin fixed paraffin embedded pre-treatment endoscopic EAC biopsies was performed using the Almac Diagnostics Xcel array. All EAC patients were treated with cisplatin-based neo-adjuvant chemotherapy followed by surgical resection between 2003 and 2014 at four UK centers in the OCCAMS consortium. Further validation was performed using a publically available dataset of 270 resected gastric cancers treated with adjuvant platinum-based CT, CRT or surgery alone at the Samsung Medical Centre, Seoul, Korea. The association between the DDRD score and prognosis was assessed by Kaplan-Meier analysis and Cox Proportional Hazards regression. Results: A total of 66 EAC samples (24%) were characterized as DDRD positive with the remaining 207 samples (76%) being DDRD negative. DDRD assay positivity was associated with improved DFS (HR 0.58; 95% CI 0.36-0.93; p = 0.024) and OS (HR 0.56; 95% CI 0.34-0.92; p = 0.023) following multivariate analysis. DDRD positive patients had a higher pathological response rate (p = 0.033) and a higher rate of loco-regional versus distant relapse (30% vs 20%; p = 0.013). For GAC, 132 samples (49%) were characterized as DDRD positive with the remaining 138 (51%) being DDRD negative. DDRD positivity was associated with improved DFS (HR 0.48; 95% CI 0.25-0.96; p = 0.037) following D2 gastrectomy and adjuvant CT or CRT. DDRD status was not associated with DFS in the surgery alone cohort (HR 0.87; 95% CI 0.55-1.38; p = 0.562). Conclusions: The DDRD assay is strongly predictive of benefit from DNA damaging neo-adjuvant CT and esophagectomy in EAC and gastrectomy and CT/CRT in GAC and can be applied to routine diagnostic material.

Challenging the Cancer Molecular Stratification Dogma: Intratumoral Heterogeneity Undermines Consensus Molecular Subtypes and Potential Diagnostic Value in Colorectal Cancer

PURPOSE

A number of independent gene expression profiling studies have identified transcriptional subtypes in colorectal cancer with potential diagnostic utility, culminating in publication of a colorectal cancer Consensus Molecular Subtype classification. The worst prognostic subtype has been defined by genes associated with stem-like biology. Recently, it has been shown that the majority of genes associated with this poor prognostic group are stromal derived. We investigated the potential for tumor misclassification into multiple diagnostic subgroups based on tumoral region sampled.

EXPERIMENTAL DESIGN

We performed multiregion tissue RNA extraction/transcriptomic analysis using colorectal-specific arrays on invasive front, central tumor, and lymph node regions selected from tissue samples from 25 colorectal cancer patients.

RESULTS

We identified a consensus 30-gene list, which represents the intratumoral heterogeneity within a cohort of primary colorectal cancer tumors. Using a series of online datasets, we showed that this gene list displays prognostic potential HR = 2.914 (confidence interval 0.9286-9.162) in stage II/III colorectal cancer patients, but in addition, we demonstrated that these genes are stromal derived, challenging the assumption that poor prognosis tumors with stem-like biology have undergone a widespread epithelial-mesenchymal transition. Most importantly, we showed that patients can be simultaneously classified into multiple diagnostically relevant subgroups based purely on the tumoral region analyzed.

CONCLUSIONS

Gene expression profiles derived from the nonmalignant stromal region can influence assignment of colorectal cancer transcriptional subtypes, questioning the current molecular classification dogma and highlighting the need to consider pathology sampling region and degree of stromal infiltration when employing transcription-based classifiers to underpin clinical decision making in colorectal cancer. Clin Cancer Res; 22(16); 4095-104. ©2016 AACRSee related commentary by Morris and Kopetz, p. 3989.

Challenging the Cancer Molecular Stratification Dogma: Intratumoral Heterogeneity Undermines Consensus Molecular Subtypes and Potential Diagnostic Value in Colorectal Cancer

PURPOSE

A number of independent gene expression profiling studies have identified transcriptional subtypes in colorectal cancer with potential diagnostic utility, culminating in publication of a colorectal cancer Consensus Molecular Subtype classification. The worst prognostic subtype has been defined by genes associated with stem-like biology. Recently, it has been shown that the majority of genes associated with this poor prognostic group are stromal derived. We investigated the potential for tumor misclassification into multiple diagnostic subgroups based on tumoral region sampled.

EXPERIMENTAL DESIGN

We performed multiregion tissue RNA extraction/transcriptomic analysis using colorectal-specific arrays on invasive front, central tumor, and lymph node regions selected from tissue samples from 25 colorectal cancer patients.

RESULTS

We identified a consensus 30-gene list, which represents the intratumoral heterogeneity within a cohort of primary colorectal cancer tumors. Using a series of online datasets, we showed that this gene list displays prognostic potential HR = 2.914 (confidence interval 0.9286-9.162) in stage II/III colorectal cancer patients, but in addition, we demonstrated that these genes are stromal derived, challenging the assumption that poor prognosis tumors with stem-like biology have undergone a widespread epithelial-mesenchymal transition. Most importantly, we showed that patients can be simultaneously classified into multiple diagnostically relevant subgroups based purely on the tumoral region analyzed.

CONCLUSIONS

Gene expression profiles derived from the nonmalignant stromal region can influence assignment of colorectal cancer transcriptional subtypes, questioning the current molecular classification dogma and highlighting the need to consider pathology sampling region and degree of stromal infiltration when employing transcription-based classifiers to underpin clinical decision making in colorectal cancer. Clin Cancer Res; 22(16); 4095-104. ©2016 AACRSee related commentary by Morris and Kopetz, p. 3989.

FKBPL: a marker of good prognosis in breast cancer

FK506-binding protein-like (FKBPL) has established roles as an anti-tumor protein, with a therapeutic peptide based on this protein, ALM201, shortly entering phase I/II clinical trials. Here, we evaluated FKBPL's prognostic ability in primary breast cancer tissue, represented on tissue microarrays (TMA) from 3277 women recruited into five independent retrospective studies, using immunohistochemistry (IHC). In a meta-analysis, FKBPL levels were a significant predictor of BCSS; low FKBPL levels indicated poorer breast cancer specific survival (BCSS) (hazard ratio (HR) = 1.30, 95% confidence interval (CI) 1.14–1.49, p < 0.001). The prognostic impact of FKBPL remained significant after adjusting for other known prognostic factors (HR = 1.25, 95% CI 1.07–1.45, p = 0.004). For the sub-groups of 2365 estrogen receptor (ER) positive patients and 1649 tamoxifen treated patients, FKBPL was significantly associated with BCSS (HR = 1.34, 95% CI 1.13–1.58, p < 0.001, and HR = 1.25, 95% CI 1.04–1.49, p = 0.02, respectively). A univariate analysis revealed that FKBPL was also a significant predictor of relapse free interval (RFI) within the ER positive patient group, but it was only borderline significant within the smaller tamoxifen treated patient group (HR = 1.32 95% CI 1.05–1.65, p = 0.02 and HR = 1.23 95% CI 0.99–1.54, p = 0.06, respectively). The data suggests a role for FKBPL as a prognostic factor for BCSS, with the potential to be routinely evaluated within the clinic.

EphA2 Expression Is a Key Driver of Migration and Invasion and a Poor Prognostic Marker in Colorectal Cancer

PURPOSE

EphA2, a member of the Eph receptor tyrosine kinases family, is an important regulator of tumor initiation, neovascularization, and metastasis in a wide range of epithelial and mesenchymal cancers; however, its role in colorectal cancer recurrence and progression is unclear.

EXPERIMENTAL DESIGN

EphA2 expression was determined by immunohistochemistry in stage II/III colorectal tumors (N = 338), and findings correlated with clinical outcome. The correlation between EphA2 expression and stem cell markers CD44 and Lgr5 was examined. The role of EphA2 in migration/invasion was assessed using a panel of KRAS wild-type (WT) and mutant (MT) parental and invasive colorectal cancer cell line models.

RESULTS

Colorectal tumors displayed significantly higher expression levels of EphA2 compared with matched normal tissue, which positively correlated with high CD44 and Lgr5 expression levels. Moreover, high EphA2 mRNA and protein expression were found to be associated with poor overall survival in stage II/III colorectal cancer tissues, in both univariate and multivariate analyses. Preclinically, we found that EphA2 was highly expressed in KRASMT colorectal cancer cells and that EphA2 levels are regulated by the KRAS-driven MAPK and RalGDS-RalA pathways. Moreover, EphA2 levels were elevated in several invasive daughter cell lines, and downregulation of EphA2 using RNAi or recombinant EFNA1 suppressed migration and invasion of KRASMT colorectal cancer cells.

CONCLUSIONS

These data show that EpHA2 is a poor prognostic marker in stage II/III colorectal cancer, which may be due to its ability to promote cell migration and invasion, providing support for the further investigation of EphA2 as a novel prognostic biomarker and therapeutic target.

Abstract 4018: The role of c-MET/HGF signaling as a critical mediator of an invasive and resistant phenotype in colorectal cancer

The c-MET proto-oncogene is frequently overexpressed (50-60%), amplified (5-10%), and mutated (5%) in colorectal cancer (CRC). Hepatocyte growth factor (HGF)-induced c-MET activation has been linked with migration, survival, invasion, and resistance to targeted therapy, and has been suggested as a possible prognostic biomarker for CRC. We are currently investigating the role of c-MET and microenvironment derived HGF in the acquisition of an invasive and migratory phenotype, and resistance to targeted therapy in CRC.

In order to model CRC tumour cell invasion and metastasis, we have generated invasive subpopulations from CRC cells using Boyden Invasion chambers. Invasive cell lines were characterised for protein expression/activity by Western blotting, and analysed for migratory and invasive potential using the xCELLigence System (Roche). To model the CRC microenvironment, we have utilised a range of co-culture techniques with CRC cell lines and colon fibroblasts. c-MET expression in FFPE tissues was measured using IHC in a tissue microarray (TMA) derived from early stage CRC patients.

HCT116 and LoVo invasive subpopulations showed an EMT-like, mesenchymal, migratory/invasive phenotype. In addition, increased expression and activation levels of c-MET were found in these sublines, which was determined to be ligand independent. Inhibition of c-MET using RNAi abrogated both basal and HGF-induced migration and invasion in CRC cell lines. Co-culture of CRC cells with HGF-expressing colon-derived fibroblasts leads to activation of c-MET, inducing CRC migration, invasion, and resistance to MEK inhibition, and this phenotype could be diminished using a HGF neutralising antibody. Significant increased expression levels of c-MET were also found in a CRC TMA compared to matched normal tissues, and also at the invasive edge of some CRC tumours, where it may be driving invasive biology.

The identification of key pathways driving metastasis has a huge potential to change treatment strategies in CRC. We intend to further investigate the role of c-MET in regulation of migration, invasion, and resistance to therapy in CRC. We hypothesise that patients with high tumoural c-MET at the invasive front may benefit in particular from anti- c-MET therapies.

Citation Format: Conor A. Bradley, Philip Dunne, Darragh McArt, Ken Arthur, Stephen McQuaid, Manuel Salto-Tellez, Patrick Johnston, Sandra Van Schaeybroeck. The role of c-MET/HGF signaling as a critical mediator of an invasive and resistant phenotype in 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 4018. doi:10.1158/1538-7445.AM2015-4018

A cross sectional study of p504s, CD133, and Twist expression in the esophageal metaplasia dysplasia adenocarcinoma sequence

The incidence of esophageal adenocarcinoma has increased dramatically over recent years and Barrett's esophagus is considered the most established risk factor for its development. Endoscopic surveillance of Barrett's esophagus is therefore recommended but hinges on histological interpretation of randomly taken biopsies which is poorly reproducible. The use of biomarkers presents an opportunity to improve our ability to risk-stratify these patients.We examined three biomarkers namely p504s, CD133, and Twist in the setting of Barrett's esophagus, low-grade dysplasia, and esophageal adenocarcinoma to evaluate differential expression between benign, dysplastic, and malignant Barrett's tissue in an exploratory cross-sectional study. Twenty-five cases each of Barrett's esophagus, low-grade dysplasia, and esophageal adenocarcinoma were included along-with 25 cases of esophagectomy resections for Barrett's adenocarcinoma. The biomarkers were immunostained on automated Ventana(®) immunostainer. The biopsies were assessed for biomarker expression by two independent observers. Granular cytoplasmic staining of p504s was observed in dysplastic Barrett's biopsies and esophageal adenocarcinoma but not in Barrett's esophagus. Apical and membranous CD133 expression was also observed in dysplastic Barrett's and esophageal adenocarcinoma. Nuclear Twist expression was seen predominantly in stromal cells. There was increased p504s expression in dysplastic Barrett's esophagus and esophageal adenocarcinoma compared with controls. CD133 expression was detected for the first time in esophageal adenocarcinoma and dysplastic Barrett's esophagus. Twist expression was not convincing enough to be labeled as Barrett's biomarker. p504s and CD133 have the potential to differentiate benign from malignant Barrett's tissue in this exploratory study. Their validity should be established in prospective longitudinal studies.

Nucleotide sequence diversity in Velvet tobacco mottle virus: a virus with a unique Australian pathosystem

Velvet tobacco mottle virus (VTMoV) is a naturally occurring mirid-transmitted sobemovirus of native velvet tobacco (Nicotiana velutina) plants in the Australian arid zone. We have sequenced the coding region of a typical field isolate of VTMoV (isolate I-17-04, satellite-plus) and show that it differed by nine polymorphisms from the previously sequenced atypical ‘satellite-minus’ variant VTMoV-K1 (represented here as L-K1-04), while retaining the same genomic and amino acid sequence motifs. We also report that although L-K1-04 was confirmed to be free of detectable satellite RNA by gel electrophoretic assay, the satellite sequence was detected in it by RT-PCR assay. Nucleotide sequence variation among the RNA-dependent RNA polymerase open reading frames of 15 field and laboratory isolates identified four phylogenetic groups, but these did not show a pattern related to site or time of sampling. This result would be consistent with nucleotide sequence variants of VTMoV being dispersed widely by migrating adult mirid vectors.

AXL is a key regulator of inherent and chemotherapy-induced invasion and predicts a poor clinical outcome in early-stage colon cancer

PURPOSE

Despite the use of 5-fluorouracil (5-FU)-based adjuvant treatments, a large proportion of patients with high-risk stage II/III colorectal cancer will relapse. Thus, novel therapeutic strategies are needed for early-stage colorectal cancer. Residual micrometastatic disease from the primary tumor is a major cause of patient relapse.

EXPERIMENTAL DESIGN

To model colorectal cancer tumor cell invasion/metastasis, we have generated invasive (KRASMT/KRASWT/+chr3/p53-null) colorectal cancer cell subpopulations. Receptor tyrosine kinase (RTK) screens were used to identify novel proteins that underpin the migratory/invasive phenotype. Migration/invasion was assessed using the XCELLigence system. Tumors from patients with early-stage colorectal cancer (N = 336) were examined for AXL expression.

RESULTS

Invasive colorectal cancer cell subpopulations showed a transition from an epithelial-to-mesenchymal like phenotype with significant increases in migration, invasion, colony-forming ability, and an attenuation of EGF receptor (EGFR)/HER2 autocrine signaling. RTK arrays showed significant increases in AXL levels in all invasive sublines. Importantly, 5-FU treatment resulted in significantly increased migration and invasion, and targeting AXL using pharmacologic inhibition or RNA interference (RNAi) approaches suppressed basal and 5-FU-induced migration and invasion. Significantly, high AXL mRNA and protein expression were found to be associated with poor overall survival in early-stage colorectal cancer tissues.

CONCLUSIONS

We have identified AXL as a poor prognostic marker and important mediator of cell migration/invasiveness in colorectal cancer. These findings provide support for the further investigation of AXL as a novel prognostic biomarker and therapeutic target in colorectal cancer, in particular in the adjuvant disease in which EGFR/VEGF-targeted therapies have failed.

Mutation rate in Velvet tobacco mottle virus varies between genomic region and virus variant but is not influenced by obligatory mirid transmission

Genomic mutation in plant viruses of cultivated plants is known to be influenced by virus, host and vector, but the factors influencing mutation in viruses of native plants in natural ecosystems are rarely studied. We have tested the effect of mode of transmission on mutation in Velvet tobacco mottle virus (VTMoV), a mirid-vectored sobemovirus associated with Nicotiana velutina, an Australian native xerophyte growing in a region isolated from anthropogenic influences. Two variants of VTMoV (K1 and R17) were passaged monthly in the alternative experimental plant host, N. clevelandii, for 2 years, either by mechanical inoculation or by transmission with the mirid Cyrtopeltis nicotianae. Sequence variations were scored after 24 passages in regions of the genome containing the open reading frames (ORFs) for the P1 and coat protein (CP). The mean mutation rate was 6.83 × 10(-4) nt/site year, but a higher overall rate was observed for the K1 (satellite -) than the R17 (satellite +) variant. The P1 ORF showed a higher frequency of non-synonymous mutations than the CP. No clear association was found between either mutation site or mutation rate and the mode of transmission, indicating that obligatory mirid transmission had not exerted a specific bottle-neck effect on sequence variation during the experimental time frame. Failure to detect any sequence motifs linked to vector transmission suggests that a specific capsid-stylet interaction is not required for transmission by mirids.

Evidence for alteration of EZH2, BMI1, and KDM6A and epigenetic reprogramming in human papillomavirus type 16 E6/E7-expressing keratinocytes

A number of epigenetic alterations occur in both the virus and host cellular genomes during human papillomavirus (HPV)-associated carcinogenesis, and investigations of such alterations, including changes in chromatin proteins and histone modifications, have the potential to lead to therapeutic epigenetic reversion. We report here that transformed HPV16 E6/E7-expressing primary human foreskin keratinocytes (HFKs) (E6/E7 cells) demonstrate increased expression of the PRC2 methyltransferase EZH2 at both the mRNA and protein levels but do not exhibit the expected increase in trimethylated H3K27 (H3K27me3) compared to normal keratinocytes. In contrast, these cells show a reduction in global H3K27me3 levels in vitro, as well as upregulation of the KDM6A demethylase. We further show for the first time that transformation with the HPV16 E6 and E7 oncogenes also results in an increase in phosphorylated EZH2 serine 21 (P-EZH2-Ser21), mediated by active Akt, and in a downregulation of the PRC1 protein BMI1 in these cells. High-grade squamous cervical intraepithelial lesions also showed a loss of H3K27me3 in the presence of increased expression of EZH2. Correlating with the loss of H3K27me3, E6/E7 cells exhibited derepression of specific EZH2-, KMD6A-, and BMI1-targeted HOX genes. These results suggest that the observed reduction in H3K27me3 may be due to a combination of reduced activities/levels of specific polycomb proteins and increases in demethylases. The dysregulation of multiple chromatin proteins resulting in the loss of global H3K27me3 and the transcriptional reprogramming in HPV16 E6/E7-infected cells could provide an epigenetic signature associated with risk and/or progression of HPV16-associated cancers, as well as the potential for epigenetic reversion in the future.

Complete nucleotide sequence of Velvet tobacco mottle virus isolate K1

Velvet tobacco mottle virus (VTMoV) infects the native Australian plant Nicotiana velutina, which is endemic to central Australia. This virus is included in the genus Sobemovirus based on virion morphology and serological relationships. We report here the full genome sequence of VTMoV, attained using a genome-walking strategy with both degenerate and specific primers. This sequence confirms that VTMoV is a sobemovirus, with the same open reading frame (ORF) organisation as other described sobemoviruses. The VTMoV sequence is closest to those sobemoviruses isolated from monocotyledonous plants, although the narrow host range of VTMoV is limited to dicotyledonous plants.

Hyperacetylation in prostate cancer induces cell cycle aberrations, chromatin reorganization and altered gene expression profiles

Histone acetylation is a fundamental mechanism in the regulation of local chromatin conformation and gene expression. Research has focused on the impact of altered epigenetic environments on the expression of specific genes and their pathways. However, changes in histone acetylation also have a global impact on the cell. In this study we used digital texture analysis to assess global chromatin patterns following treatment with trichostatin A (TSA) and have observed significant alterations in the condensation and distribution of higher-order chromatin, which were associated with altered gene expression profiles in both immortalised normal PNT1A prostate cell line and androgen-dependent prostate cancer cell line LNCaP. Furthermore, the extent of TSA-induced disruption was both cell cycle and cell line dependent. This was illustrated by the identification of sub-populations of prostate cancer cells expressing high levels of H3K9 acetylation in the G(2)/M phase of the cell cycle that were absent in normal cell populations. In addition, the analysis of enriched populations of G(1) cells showed a global decondensation of chromatin exclusively in normal cells.

Phenotypic changes in mitochondrial membrane potential (Delta psi(m)) during valinomycin-induced depolarisation and apoptosis

A large body of evidence has implicated mitochondria in control of cell death, where key apoptotic mechanisms involve change in mitochondrial membrane permeability and depolarisation of mitochondrial membrane potential (Δψ_m). Assessment of Δψ_m is traditionally conducted using the lipophilic cation JC-1 on the flow cytometer or by fluorescent microscopy. Here we assess JC-1 aggregation using the novel tool of digital texture analysis to establish mitochondrial phenotypic changes induced by the K⁺ ionophore, valinomycin in a unique model comprising SW480 and SW620 cell lines. This provides an opportunity to study these phenomena in the context of colorectal cancer. Valinomycin-induced apoptosis was detected using morphology and analysis of DNA content. Cells were treated with valinomycin, images digitally recorded on a calibrated video photometer and subjected to high resolution digital texture analysis. This demonstrated that the HARAM texture features (Mean of the Haralick texture features) were highly valuable in describing the transition of Δψ_m as the cell undergoes apoptosis. In Conclusion this study illustrates the potential of texture analysis as a novel and additional technique for quantifying JC-1 aggregation and revealing the spectrum of collapse of Δψ_m during apoptosis.

Management of aggressive histologic variants of endometrial carcinoma at the Tom Baker Cancer Centre between 1984 and 1994

OBJECTIVE

The aim of this study was to determine the patient characteristics and outcome of patients with aggressive histologic variants (AV) of endometrial carcinoma, including uterine papillary serous carcinoma (UPSC), uterine clear cell carcinoma (UCCC), and mixed type.

METHODS AND MATERIALS

All cases with AV histological type of endometrial carcinoma from January 1984 to December 1994 at the Tom Baker Cancer Centre were identified using the Alberta Cancer Registry. Relevant data from the charts of these patients were entered into a study database (Microsoft Excel) and analyzed for presentation, demography, treatment parameters, and outcome of treatment. All pathology was reviewed at the time of diagnosis. Statistical analysis was performed using the S-plus statistics computer program. Univariate and multivariate analyses were used to assess independent prognostic factors using the Cox proportional hazards model.

RESULTS

A total of 103 patients with AV histological type were identified and analyzed; there were 61, 31, and 11 cases of UPSC, CCC, and mixed tumors, respectively. Sixty-three patients had Stage I, 11 had Stage II, 15 had Stage III, and 14 had Stage IV disease. The median age of patients was 67 years with a range of 36 to 86 years. Median follow-up was 60 months with a range of 36 to 156 months. The Cox proportional hazards model showed that lymphvascular space invasion and stage are the two independent prognostic factors affecting recurrence and survival. Forty six percent of all cases underwent surgery alone, 39% underwent treatment which included pelvic RT, and 17% underwent treatment which included chemotherapy. Pelvic recurrence was reduced significantly by radiotherapy in Stages I, II, and III (19% recurrence with no RT vs 7% recurrence with RT, P < 0.005). Chemotherapy improved overall survival, but made little difference in distant relapse rates.

CONCLUSIONS

Stage Ia cases treated by surgery alone have a low risk of relapse and need not be offered adjuvant systemic therapy or pelvic radiation. Patients with Ib, Ic, II, and III have significantly lower pelvic failure rates if treated with pelvic radiation, but still have a high distant failure rate. Systemic therapy did not significantly improve distant relapse-free survival, but did extend overall survival. Stage IV patients usually died within 6 months with a few responding to systemic chemotherapy. These results suggest that there is a need for randomized trials for these patients.

Cellular proliferation and nuclear ploidy assessments augment established prognostic factors in predicting malignancy in testicular Leydig cell tumours

AIMS

Testicular Leydig cell tumours are rare. Although most behave benignly approximately 10% are malignant. Clinicopathological features have been described which have some value in predicting malignant behaviour, although as with other endocrine tumours uncertainties remain in many individual cases. Our aim was to determine the clinicopathological features of 20 testicular Leydig cell tumours. We wished to investigate whether, in addition to established clinicopathological features, the MIB1 index and/or flow cytometric analysis of nuclear DNA content are of value in predicting malignancy. We also wished to investigate the frequency of p53 protein accumulation in these neoplasms.

METHODS AND RESULTS

Twenty testicular Leydig cell tumours were studied and the clinical case notes examined. Histological sections were assessed by pathologists involved in the study. Pathological features evaluated included: tumour size, extratesticular extension, nuclear pleomorphism, mitotic activity, necrosis and vascular invasion. Immunohistochemical staining was performed with the anti-p53 monoclonal antibody DO-7 and the cell proliferation marker MIB1. A flow cytometric analysis of nuclear DNA content was also performed. Three tumours behaved in a malignant fashion with the development of metastases. Another had morphological features of malignancy but the patient died a short time after diagnosis from unrelated causes. These four neoplasms were larger than benign tumours, often contained areas of necrosis and sometimes exhibited vascular invasion. They generally exhibited greater nuclear pleomorphism and a higher mitotic rate than benign tumours. Three of the four malignant tumours had a high MIB1 index (20-50%) and the fourth exhibited DNA aneuploidy by flow cytometry. Two malignant tumours showed increased expression of p53 protein, with approximately 50% of nuclei staining with DO-7. All benign tumours had a low MIB1 index (0-2%) and a diploid DNA profile, except for one case where there was DNA aneuploidy. There was little or no staining of benign tumours with DO-7.

CONCLUSIONS

The study confirms that large size, marked nuclear pleomorphism, high mitotic rate, necrosis and vascular invasion are important factors in predicting malignant behaviour in testicular Leydig cell tumours. Additional prognostic value may be derived from the MIB1 index and flow cytometry. Accumulation of p53 protein, through mutational or other events, may be important in malignant progression in these tumours.

The utility of chest radiography in the follow-up of pneumonia

AIM

We conducted this study to determine whether chest radiography was clinically useful in the follow-up of uncomplicated pneumonia affecting children aged between 6 weeks and 15 years.

METHOD

We examined the case records of all 78 paediatric admissions for pneumonia to our hospital over one year. Thirteen children were excluded on account of age or other complicating factors.

RESULTS

Of the 65 study cases, the mean age was 3.5 years (range 0.4-13 years). On admission 51 (79%) had cough, 53 (82%) fever, 53 (82%) tachypnoea and 50 (77%) had abnormal chest signs. Elevation of C reactive protein was recorded in 43 (66%) cases and leukocytosis in 42 (65%). All children received initial chest radiographs which showed unilobular/lobar changes in 34 (53%), bilobar changes in 19 (29%) and diffuse abnormalities in 7 (11%). Forty-one patients were followed up both clinically and radiologically, usually (31 cases) between four and six weeks after discharge. Thirty-seven children had no abnormal symptoms or signs and had normal chest radiographs. The remaining four had symptoms and signs, their radiographs showed either slight resolution or no change from the admission films.

CONCLUSION

In cases of uncomplicated pneumonia, follow-up chest radiography should be deferred until at least four weeks after discharge and is not indicated if symptoms and signs are absent.

The FGF receptor-1 tyrosine kinase domain regulates myogenesis but is not sufficient to stimulate proliferation

Ligand-stimulated activation of FGF receptors (FGFRs) in skeletal muscle cells represses terminal myogenic differentiation. Skeletal muscle cell lines and subsets of primary cells are dependent on FGFs to repress myogenesis and maintain growth. To understand the intracellular events that transduce these signals, MM14 skeletal muscle cells were transfected with expression vectors encoding chimeric receptors. The chimeras are comprised of the PDGF beta receptor (PDGFbetaR) extracellular domain, the FGFR-1 intracellular domain, and either the PDGFbetaR or FGFR-1 transmembrane domain. The chimeric receptors were autophosphorylated upon PDGF-BB stimulation and are capable of stimulating mitogen-activated protein kinase activity. Activation of the tyrosine kinase domain of either chimera repressed myogenesis, suggesting intracellular responses regulating skeletal muscle differentiation are transduced by activation of the FGFR-1 tyrosine kinase. Unexpectedly, we found that activation of either chimeric receptor failed to stimulate cellular proliferation. Thus, it appears that regulation of skeletal muscle differentiation by FGFs requires only activation of the FGFR tyrosine kinase. In contrast, stimulation of proliferation may require additional, as yet unidentified, signals involving the receptor ectodomain, the FGF ligand, and heparan sulfate either alone, or in combination.

Benefit of aggressive multimodality therapy with autologous stem cell support for intra-abdominal desmoplastic small round cell tumor

A case is described of a 19-year-old man with poor prognosis intra-abdominal desmoplastic small round cell tumor, who achieved a durable complete remission after aggressive multimodality treatment. He was diagnosed with a large peri-rectal mass and bulky metastases to the peritoneum, omentum and liver. He achieved a partial response to six courses of chemotherapy with VAC (vincristine, adriamycin, actinomycin, cyclophosphamide) and VIP (VP-16, ifosfamide, cisplatin). This was followed by resection of the omentum and cryotherapy to six of the liver lesions. He then achieved a complete response following high-dose busulfan 16 mg/kg and melphalan 140 mg/m2 with autologous stem cell support. Finally, pelvic radiotherapy was given to consolidate the remission. Twenty-six months following his diagnosis, and 19 months after the transplant, he remains well with no clinical or radiologic evidence of recurrent disease. This case report suggests a role for autologous stem cell transplantation as part of multimodality therapy for this unusual and aggressive malignancy.

Cell proliferation studies in primary synovial chondromatosis

Primary synovial chondromatosis (PSC) is thought to be a cartilaginous metaplasia, but it may recur locally and malignant change has been reported. Histologically, the cartilage is usually cellular, with binucleate forms. These findings suggest that the disease is not simply a metaplasia but imply a proliferative component. In this study, immunohistochemical detection of Ki-67 protein using an antigen retrieval microwave heating technique and DNA image cytometry (VIDAS image analysis system) has been used to assess the proliferative activity in 20 cases of PSC and the results have been compared with those obtained in other cartilage tissues: ten enchondromas, ten chondrosarcomas, and ten samples of normal articular cartilage. There was no detectable staining for Ki-67 protein in cases of PSC or in benign tissues, but there was a significant association between Ki-67 labelling index and grade in the chondrosarcomas (P < 0.01). The absence of mitotic figures and the lack of Ki-67 protein in PSC are consistent with a metaplasia. All enchondromas gave diploid DNA histograms but non-diploid histograms were obtained i eight cases (40 per cent) of PSC, with significant populations of hyperdiploid and DNA aneuploid cells. The mean DNA content, the percentage of hyperdiploid cells, the percentage of DNA aneuploid cells, and the 2c deviation index were all significantly higher in PSC than in enchondromas (P < 0.01). These findings with image cytometry suggest a proliferative process in the development of at least some cases of PSC. In terms of cell proliferative activity, PSC appears to occupy a position which is intermediate between benign enchondromas and malignant chondrosarcomas, which may explain the aggressive clinical behaviour occasionally seen in this condition.

Comparison of p53 and DNA content abnormalities in adenocarcinoma of the oesophagus and gastric cardia

This study examined the association between 17p allelic loss, p53 gene mutation, p53 protein expression and DNA aneuploidy in a series of adenocarcinomas arising in the oesophagus and gastric cardia. 17p allelic loss was detected in 79% (15 of 19) of oesophageal and in 83% (29 of 35) of gastric adenocarcinomas. p53 mutations were detected in 70% (14 of 20) and 63% (26 of 41) of oesophageal and of gastric adenocarcinomas respectively. Both tumour types were associated with a predominance of base transitions at CpG dinucleotides. In five cases of oesophageal adenocarcinoma, the same mutation was detected both in tumour and in adjacent dysplastic Barrett's epithelium. Diffuse p53 protein expression was detected in 65% (13 of 20) and 59% (24 of 41) of oesophageal and of gastric tumours, respectively, and was associated with the presence of p53 missense mutation (Chi-squared, P < 0.0001). DNA aneuploidy was detected in 80% (16 of 20) of oesophageal and in 70% (28 of 40) of gastric tumours. No association was found between p53 or DNA content abnormalities and tumour stage or histological subtype. In conclusion, this study detected a similar pattern of p53 alterations in adenocarcinoma of the oesophagus and gastric cardia--molecular data consistent with the observation that these tumours demonstrate similar clinical and epidemiological features.

Prospective cohort study of neoadjuvant treatment in conservative surgery of soft tissue sarcomas

BACKGROUND

1994 marked a decade since the inception of a prospective population-based study on the value of neoadjuvant approach for soft tissue sarcomas of head, neck, and limbs at the Tom Baker Cancer Centre, Calgary, Alberta. To date, 42 patients have been followed for a minimum of 5 years or until death.

METHODS

Each patient received a protocol of 60 mg to 90 mg of Adriamycin infused intra-arterially or intravenously over 3 days into a vessel feeding the involved area, 30 Gy of radiotherapy given over 10 days, and complete resection of the sarcoma 4 to 6 weeks later. The lower dose was used empirically for smaller limbs (e.g., arm).

RESULTS

Two of the 42 patients were immediate failures of protocol, with one requiring amputation and one requiring later reexcision. In the 38 appendicular lesions, the ultimate limb salvage rate was 97.5%. All tumors were associated with a high risk of local recurrence with 15 being previous local failures. The rest were deep and grade 2 or 3 lesions. Serious local complications were seen in one patient (2.5%) who had wound necrosis requiring reoperation. Minor wound complications were seen in five patients (12.5%) (one wound infection, one resolved edema, three long-term drainage). There was one local recurrence; thus 5-year local control was 97%. No patient had long-term morbidity related to the treatment. No effect on systemic control was suggested.

CONCLUSION

Our report demonstrates that this combined modality approach provides superior local control of soft tissue sarcomas with low postoperative morbidity.

Atypical carcinoid tumor of the larynx: an immunohistochemical, ultrastructural, and flow cytometric analysis

The clinicopathologic features, including a detailed immunohistochemical, ultrastructural, and flow cytometric analysis, are described in three cases of atypical carcinoid tumor of the larynx. All patients had metastatic disease within cervical lymph nodes at presentation and eventually developed distant metastases. Special stains revealed focal intracytoplasmic mucin accumulation, and immunohistochemistry showed the tumors to be positive for CAM 5.2, CEA, chromogranin A, and calcitonin. In two cases, double-staining techniques revealed occasional cells that stained for both mucin and chromogranin A. The histochemical and immunohistochemical findings in these two cases were confirmed at the ultrastructural level, with most tumor cells containing many neurosecretory granules. Smaller numbers of cells contained mucin vacuoles and, in occasional cells, both mucin and neuroendocrine granules were identified. The three tumors exhibited positive staining with D07 (anti-p53), and flow cytometric analysis revealed DNA aneuploidy and polyploidy. The double-staining and ultrastructural features indicate that laryngeal atypical carcinoid qualifies for the designation of true amphicrine carcinoma. Further study is necessary to determine whether mutation of the p53 gene is important in the evolution of laryngeal neuroendocrine tumors and whether DNA aneuploidy or polyploidy identifies a subset of these tumors with a poor prognosis.

High-dose melphalan +/- total body irradiation and autologous hematopoietic stem cell rescue for adult patients with Ewing's sarcoma or peripheral neuroectodermal tumor

The role of high-dose therapy and autologous stem cell transplantation (ASCT) in the treatment of patients with Ewing's sarcoma (EWS) remains uncertain. From November 1985 to September 1994, 13 patients aged 16-30 years (median 20.5) received high-dose melphalan (HDM) 140-200 mg/m2 +/- 500 cGy TBI followed by ASCT for relapsed/refractory (n = 4), metastatic (n = 2), or non-metastatic (n = 6) EWS, or for peripheral neuroectodermal tumor (PNET) (n = 1). This regimen was well tolerated with no transplant-related mortality and no toxicity requiring life sustaining measures. Three of the four patients treated for relapsed/refractory EWS had progression-free survivals (PFS) less than 5 months. The only long-term survivor of these four patients received HDM while in complete remission following pulmonary irradiation. Both patients with pulmonary metastases at presentation died just 5 and 6 months post-ASCT. All four patients with non-metastatic, bulky (> 8 cm) osseous EWS progressed at a median of 11 months (range 7-22 months) while the two patients with non-bulky EWS remain progression-free 25+ and 28+ months post-HDM/TBI + ASCT. The 19-year-old patient with a PNET of the thoracoabdominal wall relapsed 4 months post-ASCT. Overall, only three of these 13 patients remain progression-free at 25+, 28+, and 108+ months following HDM +/- TBI and ASCT. In conclusion, HDM +/- TBI did not obviously improve the outcome of these 13 patients relative to that expected following conventional dose therapy alone.

p53 mutation, allele loss on chromosome 17p, and DNA content in ovarian carcinoma

The aim of this investigation was to explore the relationships between p53 mutation, DNA aneuploidy, 17p deletions, and clinical stage in ovarian cancer. Nuclear suspensions were obtained by tissue disaggregation, stained with propidium iodide, and analysed on a Coulter EPICS Elite flow cytometer. DNA cell cycle analysis was performed using Multicycle software (Phoenix Flow Systems). DNA extracted from paraffin-embedded archival carcinomas/non-tumour tissue was used as template for PCR amplification of the microsatellite dinucleotide repeat polymorphism D17S513, a locus telomeric to p53 on 17p13.1. Allele loss at D17S513 was detected in 64.5 per cent of carcinomas (20 of 31 informative cases). DNA aneuploidy was detected in 20 of 54 (37 per cent) carcinomas. Eight of ten cases previously shown to harbour p53 mutations showed aneuploid DNA content. Although ten other DNA aneuploid cases had shown no p53 mutations, the results show a statistically significant association between p53 mutation and DNA aneuploidy (P < 0.01). Furthermore, the mean DNA index of the DNA aneuploid cases was significantly higher in p53 mutant cases compared with those showing no p53 mutation (P = 0.02). There was also a significant association between p53 mutations and stage, between ploidy and stage, and between allelic deletions at D17S513 or p53 and stage, but not between these allelic deletions and ploidy. p53 mutations appear to be associated with DNA aneuploidy in ovarian cancer independently of 17p deletions. p53 mutations, DNA aneuploidy, and 17p deletions are associated with late stage.

Flow cytometric analysis does not reliably differentiate benign from malignant phaeochromocytoma

BACKGROUND AND OBJECTIVE

The differentiation of benign from malignant phaeochromocytoma is difficult. We have examined whether the use of flow cytometric determination of nuclear DNA content would be useful as a predictor of malignant behaviour in patients with phaeochromocytoma as some previous studies had suggested that a diploid cytometric DNA pattern indicated benign disease.

DESIGN AND PATIENTS

DNA flow cytometry was performed on phaeochromocytoma tissue from 36 patients (19 female, 17 male; mean age at presentation 39.5 years). The results were correlated with clinical outcome after prolonged follow-up.

MEASUREMENTS

DNA histograms were constructed following nuclear suspension analysis.

RESULTS

Of 26 patients followed up for more than 5 years after initial removal of primary phaeochromocytoma, three have died from malignant recurrence. In these patients a diploid DNA cytometric pattern was observed in two and an aneuploid pattern in one. Twenty-one patients are still alive. DNA cytometry showed a diploid pattern in the one patient who developed recurrent phaeochromocytoma 4 years after removal of a primary tumour.

CONCLUSION

In this study, three of nine patients with an apparently benign diploid cytometric pattern subsequently developed recurrent disease. Routine use of DNA flow cytometry did not reliably differentiate benign from malignant phaeochromocytoma. Prolonged clinical and biochemical follow-up is still necessary for all patients with this condition.

Simple isotope dilution assay for propionic acid and isovaleric acid

A gas chromatographic-mass spectrometric method is described for the assay of propionic acid and of isovaleric acid in physiological fluids by isotope dilution. The acids are derivatized to the pentafluorobenzyl esters to decrease volatility to render them suitable for GC-MS analysis. The following reference values were found. Propionic acid: plasma 0.54 +/- 0.38 mumol/l (n = 13, range 0.03-1.38 mumol/l), urine 1.7 +/- 1.6 mumol/mmol creatinine (n = 9, range 0.1-4.9 mumol/mmol creatinine). Isovaleric acid: plasma 0.89 +/- 0.93 mumol/l (n = 10, range 0.01-3.03 mumol/l), urine 0.38 +/- 0.51 mumol/mmol creatinine (n = 10, range 0.01-1.70 mumol/mmol creatinine).

Phase II study to evaluate the toxicity and efficacy of concurrent cisplatin and radiation therapy in the treatment of patients with locally advanced squamous cell carcinoma of the cervix

Sixty patients presenting with poor prognosis squamous cell cancer of the cervix have been studied in a phase II clinical trial. Patients were treated with radiotherapy and concurrent cisplatin chemotherapy every 10 days. Treatment was well tolerated with all patients completing radiotherapy as prescribed. There was one case of grade 4 acute bowel toxicity. Significant late morbidity was acceptable for this group of patients being restricted to two cases (3.3%) of grade 4 toxicity to the bowel. Pelvic control rates of 78% have been observed. There have been no pelvic recurrences after 26 months, although recurrences beyond the pelvis have occurred up to 4 years later. Actuarial 4-year survival is encouraging at 60%.

Limb salvage surgery for widely infiltrating bony sarcomas

OBJECTIVE

To determine whether neoadjuvant chemotherapy and radiotherapy for bony sarcomas extending into soft tissues would allow limb salvage yet maintain local disease control.

DESIGN

A prospective cohort study.

SETTING

A university-affiliated cancer centre in Alberta.

PATIENTS

All patients with potentially curable, widely infiltrating bony sarcomas of the extremity without neurologic deficit, referred to the centre in the 6 years from January 1984 to December 1990. There were 11 patients; 1 did not complete the protocol. The mean follow-up was 24 months.

INTERVENTIONS

Adriamycin (doxorubicin) was infused for 3 days at a rate of 30 mg/d. A few days later radiotherapy was given 5 days a week for 10 doses at a rate of 3.0 Gy per dose. Four to 5 weeks later the tumour was excised surgically, with placement of a bone allograft or prosthesis, allowing a 1-cm margin of healthy soft tissue and a 5-cm margin of healthy bone and marrow cavity whenever possible.

MAIN OUTCOME MEASURES

Need for limb amputation, infectious complications, recurrence of local or regional disease.

RESULTS

One patient underwent amputation after fracture through the tumour site. There were two postoperative infections, one acute and one chronic. All patients had full neurologic function of the distal limb. There was no local or regional recurrence of disease.

CONCLUSION

Neoadjuvant chemotherapy followed by radiotherapy and tumour excision provides control of aggressive local bone sarcomas while maintaining limb integrity.

Therapy with recombinant human erythropoietin in patients with myelodysplastic syndromes

We conducted a Phase I-II trial of recombinant human erythropoietin-beta (rhEPO) in patients with myelodysplastic syndrome (MDS). Patients with anemia and pathologically confirmed MDS were eligible for the study. Treatment consisted of rhEPO by subcutaneous injection thrice weekly for 6 weeks at one of three dose levels (100 U/kg (three patients), 200 U/kg (three patients) and 400 U/kg (14 patients)). Ferrous sulfate (325 mg po tid) was also administered if the transferrin saturation was below 30% (two patients). Patients were monitored with weekly CBC, white cell differential, and reticulocyte counts. Bone marrow examinations were performed at the conclusion of the treatment period and after a 2 week washout period. Patients who responded to therapy were continued on rhEPO at the same dose for 6 additional months. Response criteria included: 50% reduction in transfusion requirements compared with the 6 week pre-study period; doubling of reticulocyte count that was maintained on two determinations at least 1 week apart; or an increase in hemoglobin by at least 1.2 gm/dl without transfusions. Pre-treatment factors potentially predictive of response were analyzed by univariate analysis and in a multivariate fashion by classification and regression trees. Seven of the twenty patients sustained an untransfused rise in serum hemoglobin > or = 1.2 gm/dl. Four of the sixteen patients (including three of seven patients experiencing a rise in serum hemoglobin) who were transfusion-dependent prior to the study achieved a reduction or elimination of their transfusion requirements. Five of thirteen patients who received rhEPO during the extension phase had a continued response. A low baseline erythropoietin level (< 50 mU/ml) was the best predictor of hemoglobin response when controlling for other variables. rhEPO has a role in the treatment of certain patients with MDS, particularly in those whose endogenous serum erythropoietin levels are not markedly elevated.

Role of FGFs in skeletal muscle and limb development

Fibroblast growth factors (FGFs) are a family of nine proteins that bind to three distinct types of cell surface molecules: (i) FGF receptor tyrosine kinases (FGFR-1 through FGFR-4); (ii) a cysteine-rich FGF receptor (CFR); and (iii) heparan sulfate proteoglycans (HSPGs). Signaling by FGFs requires participation of at least two of these receptors: the FGFRs and HSPGs form a signaling complex. The length and sulfation pattern of the heparan sulfate chain determines both the activity of the signaling complex and, in part, the ligand specificity for FGFR-1. Thus, the heparan sulfate proteoglycans are likely to play an essential role in signaling. We have recently identified a role for FGF in limb bud development in vivo. In the chick limb bud, ectopic expression of the 18 kDa form of FGF-2 or FGF-2 fused to an artificial signal peptide at its amino terminus causes skeletal duplications. These data, and the observations that FGF-2 is localized to the subjacent mesoderm and the apical ectodermal ridge in the early developing limb, suggest that FGF-2 plays an important role in limb outgrowth. We propose that FGF-2 is an apical ectodermal ridge-derived factor that participates in limb outgrowth and patterning.

Three-dimensional computerised analysis of epithelial cell proliferation in the gastrointestinal tract

This study describes a new technique for the visualisation and quantitation of glandular epithelial cell proliferation in gastrointestinal mucosa using computerised three-dimensional reconstruction. The tissue used in this study was colorectal biopsy tissue infiltrated in vitro with bromodeoxyuridine (BrdU), although the method could be applied to any gastrointestinal site labelled with any specific marker for cell proliferation. The method is as follows. Five-micron-thick serial sections (> 100) were cut from colorectal biopsies infiltrated in vitro with BrdU. After labelling all the sections for BrdU-positive cells using standard immunohistochemistry, colorectal glands were identified which were completely sectioned within the series. Each microscopic image of the sectioned gland was orientated, digitised and stored using a Kontron image analyser. On each of the stored images, the crypt profile, the positive cells and the negative cells were interactively marked and digitally stored. Using three-dimensional (3-D) reconstruction software, the outer surface of the crypt, the total positive and the total negative fractions could be viewed in three dimensions. The total BrdU-positive cell number could be automatically calculated for the complete crypt or, alternatively, compartmental analysis of the labelling pattern within the crypt could be obtained. This represents a powerful technique: it does not require orientation, it can be carried out on complex glandular structures and is not affected by the biases involved in measuring labelling indices from single tissue sections.

Intraosseous infusion: success of a standardized regional training program for prehospital advanced life support providers

STUDY OBJECTIVE

To evaluate a standardized training program in intraosseous (IO) infusion for prehospital providers.

DESIGN

Prospective multicenter 24-month study.

SETTING

IO infusions were performed by prehospital providers from eight advanced life support units serving 14 hospitals within nine counties.

PARTICIPANTS

Field advanced life support providers (paramedics and registered nurses).

INTERVENTIONS

All providers participated in a one-hour standardized training session and supervised hands-on simulation. Providers completed a data sheet on all IO infusions performed. Data sheets were collected and summarized.

RESULTS

One hundred thirty-four prehospital providers completed the training session and were approved to perform the procedure. Fifteen patients requiring IO infusion were encountered during the study period. Thirteen (87%) had IO infusion completed successfully. Clinical indications included 11 patients in cardiac arrest, two trauma resuscitations, one seizure, and one toxic ingestion. Patient ages ranged from 1 to 24 months. Seven patients were initially resuscitated. Four survived to hospital discharge. Procedural complications included one incidence of local fluid extravasation and one IO line that became dislodged en route. There were no complications at time of discharge in the four survivors. All procedures were performed in less than two minutes.

CONCLUSION

A one-hour standardized training session was successfully used to train prehospital providers in the procedure of IO infusion. IO infusion then was implemented into their clinical practice with a satisfactory success rate and few complications.

Morphometry of gastric carcinoma: its association with patient survival, tumour stage, and DNA ploidy

Morphometric image analysis of nuclear features was performed on tissue from 46 patients who had had curative resections for gastric cancer. Clinical, pathological, flow cytometric, and follow-up data were available for these patients, which were drawn from a larger, previously reported series. The morphometric data were compared with patient survival, clinico-pathological status, and DNA ploidy. Univariate survival analysis revealed that morphometric parameters were not significantly related to survival, but examination of clinico-pathological data showed lymph node involvement, involvement of the resection margin, and lymphatic invasion to be significantly associated (P < 0.01) with patient prognosis. Multivariate survival analysis using the Cox model found only lymph node and resection margin involvement to be independently related to survival. Comparison of morphometric results with the clinico-pathological parameters showed various features, relating to nuclear size, and its variation to be significantly associated (P < 0.01) with the presence of lymphatic invasion, resection margin involvement, and tumour pattern (intestinal/diffuse). A comparison of morphometry with flow cytometric analysis in these cases showed that nuclear size was not significantly related to either DNA aneuploidy or the DNA proliferative index.

Tumor necrosis factor expression by human ovarian carcinoma in vivo

Tumor necrosis factor (TNF) is a cytokine produced by monocytes and other cells with selective cytolytic activity against some but not all tumor cells. Cellular resistance to the cytolytic effects of TNF has been reported to be associated with autocrine production of TNF by the target cells. The purpose of this study was to determine whether or not human tumors produce tumor necrosis factor in vivo. Ovarian carcinoma tissue from 25 patients with ovarian carcinoma was examined for the presence of TNF. Four of 5 ascites fluid specimens and tissue sections of 16 of 20 patients were positive for TNF by immunoperoxidase staining. The source of the immunoreactive protein was further examined by in situ hybridization studies. TNF mRNA was detectable in each of the ascites specimens and 7 of 16 tissue sections that were positive by immunoperoxidase staining. These findings suggest that TNF is produced by some human tumors in vivo and that the association between TNF production and resistance to TNF antitumor action may be clinically relevant.