Abstract 1018: Multiplex immunofluorescence and image analysis to investigate the role of the immune contexture and fibroblast activation for tumor cell budding in colorectal cancer

The advent of immune oncology had a significant impact on the stratification of cancer patients in the past few years. Furthermore, immune cell phenotyping of the tumor microenvironment is becoming a tool not only for the identification of novel predictive biomarkers for cancer immunotherapy, but also for prognostic markers that may help to understand several mechanisms like invasion and epithelial-mesenchymal transition (EMT). We demonstrate how multiplexed immunofluorescence (mIF) assays and digital image analysis helped to investigate tumor budding in colorectal cancer by evaluating the tumor microenvironment and activated fibroblasts. Akoya Bioscience’s Opal detection system and fluorophores were optimized on LEICA Bond RX for use with human normal tonsil control tissues and FFPE colorectal cancer specimens. The 6-plex mIF panel included CD4 (clone SP35), CD8 (clone C8/144B), CD68 (clone PG-M1), FoxP3 (clone SP97), PD-L1 (clone SP263) and pan-Cytokeratin (clones AE1/AE3). In addition, FAP-alpha single-plex IHC was used to investigate reactivity of the stroma surrounding tumor cell buds.  Each single marker of the mIF panel was independently validated for specificity regarding stripping efficacy and epitope stability, and for accuracy compared to single plex bright field immunohistochemistry.  Automated image analysis and cellular phenotyping followed a workflow of custom Visiopharm apps. The tissue was segmented into regions of interest, such as areas with and without tumor cell budding, and bud microenvironment. Additional parameters like MSI (Microsatellite Instability) status and TNM classification were also taken into consideration for data analysis. The applied mIF immune cell panel and automated image analysis workflow identified a broad number of different immune cell phenotypes, including rare double- or triple-positive cell subtypes, as well as their spatial relation to tumor cell buds within the activated stroma region. This revealed new insights into the complexity of the tumor microenvironment in colorectal cancer around tumor cell buds, suggesting a potential effect of both the immune system and the stromal cells on tumor cell invasion into the surrounding tissue.

Citation Format: Dirk Zielinski, Rebekka Vogtmann, Anne Siemon, Christina Koppel, Christina Schipper, Anastasiia Tereshchenko, Suso Platero, Hans-Ulrich Schildhaus. Multiplex immunofluorescence and image analysis to investigate the role of the immune contexture and fibroblast activation for tumor cell budding in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1018.

"Interchangeability" of PD-L1 immunohistochemistry assays: a meta-analysis of diagnostic accuracy

Different clones, protocol conditions, instruments, and scoring/readout methods may pose challenges in introducing different PD-L1 assays for immunotherapy. The diagnostic accuracy of using different PD-L1 assays interchangeably for various purposes is unknown. The primary objective of this meta-analysis was to address PD-L1 assay interchangeability based on assay diagnostic accuracy for established clinical uses/purposes. A systematic search of the MEDLINE database using PubMed platform was conducted using "PD-L1" as a search term for 01/01/2015 to 31/08/2018, with limitations "English" and "human". 2,515 abstracts were reviewed to select for original contributions only. 57 studies on comparison of two or more PD-L1 assays were fully reviewed. 22 publications were selected for meta-analysis. Additional data were requested from authors of 20/22 studies in order to enable the meta-analysis. Modified GRADE and QUADAS-2 criteria were used for grading published evidence and designing data abstraction templates for extraction by reviewers. PRISMA was used to guide reporting of systematic review and meta-analysis and STARD 2015 for reporting diagnostic accuracy study. CLSI EP12-A2 was used to guide test comparisons. Data were pooled using random-effects model. The main outcome measure was diagnostic accuracy of various PD-L1 assays. The 22 included studies provided 376 2×2 contingency tables for analyses. Results of our study suggest that, when the testing laboratory is not able to use an Food and Drug Administration-approved companion diagnostic(s) for PD-L1 assessment for its specific clinical purpose(s), it is better to develop a properly validated laboratory developed test for the same purpose(s) as the original PD-L1 Food and Drug Administration-approved immunohistochemistry companion diagnostic, than to replace the original PD-L1 Food and Drug Administration-approved immunohistochemistry companion diagnostic with a another PD-L1 Food and Drug Administration-approved companion diagnostic that was developed for a different purpose.

Optimization and validation of PD-L1 immunohistochemistry staining protocols using the antibody clone 28-8 on different staining platforms

Several immunohistochemistry (IHC) assays have been developed to assess tumor programmed death-ligand 1 (PD-L1) expression levels in patients who are candidates for programmed death-1 (PD-1)/PD-L1 inhibitor therapy. The PD-L1 IHC 28-8 pharmDx kit is FDA-approved as a complementary diagnostic and CE-marked as an in vitro diagnostic device for nivolumab therapy in melanoma and specific lung cancer subtypes (and for squamous cell carcinoma of the head and neck/urothelial carcinoma in Europe only). Kit availability is limited outside the United States, and its use requires the Dako Autostainer Link 48 platform, which is unavailable in many laboratories. Validated laboratory-developed tests based on 28-8 concentrated antibody outside the kit are needed. This study compared the results from PD-L1 expression level analysis across four immunohistochemistry platforms (Dako Autostainer Link 48, Dako Omnis, Leica Bond-III, and Ventana BenchMark ULTRA) with the 28-8 pharmDx kit in lung cancer (multiple histologies), melanoma, and head and neck cancer (multiple histologies). Samples were prepared per protocol for each platform and stained using PD-L1 IHC 28-8 pharmDx kit on Dako Autostainer Link 48, and per protocol for each platform. The control samples (tonsil and placenta tissue; cell lines with prespecified PD-L1 expression levels) were tested to evaluate the specificity and the sensitivity of test assays. An agreement level of 0.90 with the pharmDx kit was set for each platform. Inter- and intra-assay reliability were assessed. Evaluable samples were lung cancer = 29; melanoma = 31; head and neck cancer = 30. Mean agreement was calculated for PD-L1 expression levels of ≥1%, ≥5%, ≥10%, and ≥50%. Mean overall agreement for all indications was 0.87-0.99. Inter- and intra-assay of scoring/classification repeatability was 100%. Analysis of PD-L1 expression levels using laboratory-developed immunohistochemistry assays with 28-8 antibody may be permissible if the platform is validated using reference samples with defined expression levels.

FGFR3 mRNA overexpression defines a subset of oligometastatic colorectal cancers with worse prognosis

Objectives

Metastatic colorectal cancer (CRC) remains a leading cause of cancer related deaths. Patients with oligometastatic liver disease represent a clinical subgroup with heterogeneous course. Until now, biomarkers to characterize outcome and therapeutic options have not been fully established.

Methods

We investigated the prevalence of FGFR alterations in a total of 140 primary colorectal tumors and 63 liver metastases of 55 oligometastatic CRC patients. FGF receptors (FGFR1-4) and their ligands (FGF3, 4 and 19) were analyzed for gene amplifications and rearrangements as well as for RNA overexpression in situ. Results were correlated with clinico-pathologic data and molecular subtypes.

Results

Primary tumors showed FGFR1 (6.3%) and FGF3,4,19 (2.2%) amplifications as well as FGFR1 (10.1%), FGFR2 (5.5%) and FGFR3 (16.2%) overexpression. In metastases, we observed FGFR1 amplifications (4.8%) as well as FGFR1 (8.5%) and FGFR3 (14.9%) overexpression. Neither FGFR2-4 amplifications nor gene rearrangements were observed. FGFR3 overexpression was significantly associated with shorter overall survival in metastases (mOS 19.9 vs. 47.4 months, HR=3.14, p=0.0152), but not in primary CRC (HR=1.01, p=0.985). Although rare, also FGFR1 amplification was indicative of worse outcome (mOS 12.6 vs. 47.4 months, HR=8.83, p=0.00111).

Conclusions

We provide the so far most comprehensive analysis of FGFR alterations in primary and metastatic CRC. We describe FGFR3 overexpression in 15% of CRC patients with oligometastatic liver disease as a prognosticator for poor outcome. Recently FGFR3 overexpression has been shown to be a potential therapeutic target. Therefore, we suggest focusing on this subgroup in upcoming clinical trials with FGFR-targeted therapies.

Patient selection using novel RNA-based approaches: Early experience from a phase I study with the pan-FGFR inhibitor BAY 1163877 in patients with urothelial bladder cancer

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Background: FGFRs play a role in a variety of malignancies, including urothelial bladder cancer (UBC). Whereas genetic alterations of FGFRs in UBC are known, non-genetic and epigenetic activation of FGFR gene expression have also been described. BAY 1163877 is an oral inhibitor of FGFRs 1-3 with antitumor activity in FGFR mRNA overexpressing xenograft models not limited to DNA alterations. We report the results from a phase I expansion cohort in UBC patients pre-screened for treatment with BAY 1163877 based on FGFR1-3 mRNA overexpression and/or activating mutations in the FGFR3 gene. Methods: FGFR mRNA levels were assessed in paraffin-embedded archival or fresh biopsy specimens by RNAscope and NanoString technology and activating mutations by RT-PCR-based mutation assay. Tumor response to treatment was assessed by RECIST, v1.1. Adverse events were assessed using CTCAE v4.03 criteria. Results: A total of 80 patients from multiple indications were enrolled in the phase I study; 800 mg BID was established as the recommended phase 2 dose. Sixty seven UBC patients were screened, with 31 tumor biopsies (46%) determined to overexpress FGFR mRNA: 2 patients each with FGFR1 and FGFR2, and 27 patients with FGFR3. Of the 27 patients with FGFR3 mRNA overexpression, 5 had in parallel an activating mutation in FGFR3 gene. Eight UBC patients met eligibility criteria and entered treatment; all had elevated FGFR3 mRNA expression and 4 had alterations in FGFR3 DNA (3 mutations and 1 translocation). Seven patients (87.5%) had tumor shrinkage in target lesions as best response, with 3/8 partial responses (PR; 37.5%). One patient with a PR presented with elevated FGFR3 mRNA without evidence of aberrant DNA. BAY 1163877 was generally well tolerated and AEs manageable with dose modification. The most common AEs in the overall population were increased phosphorus (66% all grade, 1 grade-3 event) and diarrhea (33% all grade, 2 grade-3 events). Conclusions: Selection of patients for treatment with BAY 1163877 based on FGFR mRNA expression levels in archival tissue was feasible. BAY 1163877 had a favorable safety profile and promising anti-tumor activity in UBC patients. Clinical trial information: NCT01976741.

Serum Autoantibodies in Chronic Prostate Inflammation in Prostate Cancer Patients

Background

Chronic inflammation is frequently observed on histological analysis of malignant and non-malignant prostate specimens. It is a suspected supporting factor for prostate diseases and their progression and a main cause of false positive PSA tests in cancer screening. We hypothesized that inflammation induces autoantibodies, which may be useful biomarkers. We aimed to identify and validate prostate inflammation associated serum autoantibodies in prostate cancer patients and evaluate the expression of corresponding autoantigens.

Methods

Radical prostatectomy specimens of prostate cancer patients (N = 70) were classified into high and low inflammation groups according to the amount of tissue infiltrating lymphocytes. The corresponding pre-surgery blood serum samples were scrutinized for autoantibodies using a low-density protein array. Selected autoantigens were identified in prostate tissue and their expression pattern analyzed by immunohistochemistry and qPCR. The identified autoantibody profile was cross-checked in an independent sample set (N = 63) using the Luminex-bead protein array technology.

Results

Protein array screening identified 165 autoantibodies differentially abundant in the serum of high compared to low inflammation patients. The expression pattern of three corresponding antigens were established in benign and cancer tissue by immunohistochemistry and qPCR: SPAST (Spastin), STX18 (Syntaxin 18) and SPOP (speckle-type POZ protein). Of these, SPAST was significantly increased in prostate tissue with high inflammation. All three autoantigens were differentially expressed in primary and/or castration resistant prostate tumors when analyzed in an inflammation-independent tissue microarray. Cross-validation of the inflammation autoantibody profile on an independent sample set using a Luminex-bead protein array, retrieved 51 of the significantly discriminating autoantibodies. Three autoantibodies were significantly upregulated in both screens, MUT, RAB11B and CSRP2 (p>0.05), two, SPOP and ZNF671, close to statistical significance (p = 0.051 and 0.076).

Conclusions

We provide evidence of an inflammation-specific autoantibody profile and confirm the expression of corresponding autoantigens in prostate tissue. This supports evaluation of autoantibodies as non-invasive markers for prostate inflammation.

HER2 staining intensity in HER2-positive disease: relationship with FISH amplification and clinical outcome in the HERA trial of adjuvant trastuzumab

BACKGROUND

Trastuzumab treatment improves survival of HER2-positive primary breast cancer. HER2 staining intensity varies widely in HER2-positive tumours.

PATIENTS AND METHODS

We investigated whether differences in immunohistochemical (IHC) staining intensity for HER2 in HER2-positive tumors (IHC 3+ or FISH ratio ≥2.0) was associated with prognosis or benefit from trastuzumab treatment in patients randomized to 1 year or no trastuzumab in the HERceptin Adjuvant (HERA) trial. Median follow-up was 2 years. The nested case-control analysis, included 425 patients (cases) with a disease-free survival (DFS) event and two matched controls (no DFS event) per case. Tissue sections stained for HER2 were assessed for HER2 staining intensity by image analysis.

RESULTS

HER2 staining intensity varied widely and correlated with HER2 gene copy number (Spearman, r = 0.498, P < 0.001) or less closely with HER2/CEP17 FISH ratio (r = 0.396, P < 0.001). We found no significant difference in DFS in the observation arm according to staining intensity (odds ratio [OR] change per 10 unit change in intensity: 1.015, 95% confidence interval [CI] 0.930-1.108) and no impact of staining intensity on benefit derived from 1-year trastuzumab (OR: 1.017, 95% CI 0.925-1.120).

CONCLUSIONS

Variability in HER2 staining in HER2-positive tumours has no role in clinical management with adjuvant trastuzumab.

HERA TRIAL NO

NCT00045032.

Reduced mRNA expression in paraffin-embedded tissue identifies MLH1- and MSH2-deficient colorectal tumours and potential mutation carriers

Based on the principle of nonsense-mediated mRNA decay, we sought to identify MLH1 or MSH2-deficient colorectal tumours through relative quantification of mRNA expression with real-time PCR (RT-PCR) analysis. MLH1 and MSH2 mRNAs were almost equally expressed as defined by MLH1 to MSH2 transcript ratio (mean 1.41) in microsatellite stable, mismatch repair (MMR) proficient tumours (n = 16). A close correlation between loss of protein expression and MMR-mRNA levels was found in highly microsatellite instable (MSI-H) tumours deficient of MLH1 or MSH2. MLH1/MSH2 ratio was low in 11 sporadic and nine hereditary MLH1-deficient carcinomas (mean 0.51), whereas the ratio was high in 17 MSH2-deficient hereditary non-polyposis colorectal cancer (HNPCC) associated carcinomas (mean 6.8). Notably, in the normal tissues of HNPCC patients with MSH2 mutations, the MLH1/MSH2 transcript ratios were significantly elevated (ratio > 2.0) as compared to the ratios of normal mucosa in patients with MMR-proficient tumours (27 of 32 ratio < 2.0; p = 0.00113). Analysis of B-lymphocytes of HNPCC patients with proven MMR gene mutation confirmed these findings. In conclusion, RT-PCR allows relative quantification of MMR gene mRNA expression in formalin-fixed and paraffin-embedded tissue. Furthermore, this approach enables quantification of haploinsufficiency due to nonsense-mediated mRNA decay in normal tissue and B-lymphocytes from patients carrying MSH2 germline mutations and may be useful for identification of asymptomatic carriers of pathogenic germline mutations.

Transcriptional profiling of transurethral resection samples provides insight into molecular mechanisms of hormone refractory prostate cancer

The molecular mechanisms for hormone-resistant prostate cancer progression still remain elusive, mainly due to the limited availability of corresponding tissue. As transurethral resection (TUR) is a common palliative therapy for patients with hormone refractory prostate cancer (HRPC) who have subvesical obstruction, we aimed to demonstrate that TUR samples can be used to identify significantly affected biological pathways during the switch to HRPC using oligonucleotide microarray analysis. Among the most significantly deregulated pathways in HRPC, we observed an induction of oxidative phosphorylation and a repression of cytoskeletal components.

Molecular analysis of hormone refractory prostate cancer biopsies supports the rationale of using mTOR inhibitors

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Background: The aim of our group is to identify molecular signatures in samples of hormone refractory prostate cancer (HRPC) patients (pts) that lead to novel rationales for medical treatment. We have previously shown that transurethral resections (TUR) of the prostate in HRPC pts are useful specimens for gene expression profiling using microarrays (ASCO 2006). Aim of this study was to prove the feasibility of gene expression profiling on prostate biopsies and to develop a standardised tissue handling protocol in order to facilitate multicenter research. Methods: Biopsy material and corresponding TUR chips or classical specimens from 8 pts with HRPC, 13 pts with localized PCA, 6 pts with benign prostatic hyperplasia (BPH) and 11 pts without cancer or BPH were investigated and compared. The tumor type and content was evaluated by a pathologist. Tissues were preserved in liquid nitrogen or RNAlater. Different tissue lysis and RNA purification methods were compared by the quantity (NanoDrop measurement) and quality (Bioanalyser, Agilent) of isolated RNA. Gene expression profiling occurred on Affymetrix HG-FOCUS arrays. Results: Most reliable gene expression results were obtained by biopsy lysis in Trizol using the QIAshredder. A total of more than 1 μg RNA was isolated from one biopsy. RNA quality fulfilled pre-defined criteria such as a 28S/18S rRNA ratio of > 0.8, an area under the curve of > 10% and a RNA integrity number > 6.5. A comparison of HRPC and PCA samples clearly confirmed previous results of a deregulation of protein biosynthesis (translation initiation and elongation factors, ribosome biogenesis) and PI3K signalling pathway components. Conclusions: Gene expression profiling supports the induction of the PI3K-AKT-mTOR pathway in HRPC. A standardised protocol for gene expression profiling from prostate biopsy samples applicable for translational research programs within multicenter clinical trials is now available. As a part of a clinical phase II trial that aims to investigate survival benefits on HRPC pts treated with docetaxel ± RAD001, a translational research program is now set up in parallel to identify biomarkers for response prediction using microarray gene expression analysis from prostate biopsies.

No significant financial relationships to disclose.

Heat stress response in plants: a complex game with chaperones and more than twenty heat stress transcription factors

Compared to the overall multiplicity of more than 20 plant Hsfs, detailed analyses are mainly restricted to tomato and Arabidopsis and to three important representatives of the family (Hsfs A1, A2 and B1). The three Hsfs represent examples of striking functional diversification specialized for the three phases of the heat stress (hs) response (triggering, maintenance and recovery). This is best illustrated for the tomato Hsf system: (i) HsfA1a is the master regulator responsible for hs-induced gene expression including synthesis of HsfA2 and HsfB1. It is indispensible for the development of thermotolerance. (ii) Although functionally equivalent to HsfA1a, HsfA2 is exclusively found after hs induction and represents the dominant Hsf, the "working horse" of the hs response in plants subjected to repeated cycles of hs and recovery in a hot summer period. Tomato HsfA2 is tightly integrated into a network of interacting proteins (HsfA1a, Hsp17-CII, Hsp17-CI) influencing its activity and intracellular distribution. (iii) Because of structural peculiarities, HsfB1 acts as coregulator enhancing the activity of HsfA1a and/or HsfA2. But in addition, it cooperates with yet to be identified other transcription factors in maintaining and/or restoring housekeeping gene expression.

Tomato heat stress protein Hsp16.1-CIII represents a member of a new class of nucleocytoplasmic small heat stress proteins in plants

We describe a new class of plant small heat stress proteins (sHsps) with dominant nuclear localization (Hsp17-CIII). The corresponding proteins in tomato, Arabidopsis, and rice are encoded by unique genes containing a short intron in the beta4-encoding region of the alpha-crystallin domain (ACD). The strong nuclear localization results from a cluster of basic amino acid residues in the loop between beta5 and beta6 of the ACD. Using yeast 2-hybrid tests, analyses of native complexes of the sHsps, and immunofluorescence data, we demonstrate that, in contrast to earlier observations (Kirschner et al 2000), proteins of the sHsp classes CI, CII, and CIII interact with each other, thereby influencing oligomerization state and intracellular localization.

Role of Hsp17.4-CII as coregulator and cytoplasmic retention factor of tomato heat stress transcription factor HsfA2

HsfA2 is a heat stress (hs)-induced Hsf in peruvian tomato (Lycopersicon peruvianum) and the cultivated form Lycopersicon esculentum. Due to the high activator potential and the continued accumulation during repeated cycles of heat stress and recovery, HsfA2 becomes a dominant Hsf in thermotolerant cells. The formation of heterooligomeric complexes with HsfA1 leads to nuclear retention and enhanced transcriptional activity of HsfA2. This effect seems to represent one part of potential molecular mechanisms involved in its activity control. As shown in this paper, the activity of HsfA2 is also controlled by a network of nucleocytoplasmic small Hsps influencing its solubility, intracellular localization and activator function. By yeast two-hybrid interaction and transient coexpression studies in tobacco (Nicotiana plumbaginifolia) mesophyll protoplasts, we found that tomato (Lycopersicon esculentum) Hsp17.4-CII acts as corepressor of HsfA2. Given appropriate conditions, both proteins together formed large cytosolic aggregates which could be solubilized in presence of class CI sHsps. However, independent of the formation of aggregates or of the nucleocytoplasmic distribution of HsfA2, its transcriptional activity was specifically repressed by interaction of Hsp17.4-CII with the C-terminal activator domain. Although not identical in all aspects, the situation with the highly expressed, heat stress-inducible Arabidopsis HsfA2 was found to be principally similar. In corresponding reporter assays its activity was repressed in presence of AtHsp17.7-CII but not of AtHsp17.6-CII or LpHsp17.4-CII.

Validation of a flow cytometric acridine orange micronuclei methodology in rats

Our laboratory has previously reported a flow cytometric acridine orange method for detection of micronucleus (MN) in the rat using cyclophosphamide as a test compound. To replace the manual method of scoring and satisfy Good Laboratory Practice (GLP) requirements, an extensive validation of the flow method was required. Therefore, manual scoring and flow cytometric determination of MN were compared using vincristine, chlorambucil, methotrexate, and doxorubicin compounds known to induce MN formation with various mechanisms of action. 1,2-Dimethylhydrazine (1,2-DH), a compound with negative or equivocal MN findings also was evaluated. The flow method consistently demonstrated dose- and time-dependent responses for MN production at all concentrations of vincristine, methotrexate, clorambucil, and doxorubicin. In contrast, manual scoring of slides failed to detect an increase in MN at the lowest doses of doxorubicin (1mg/kg) at 24 or 48 h, and methotrexate at 48 h, or any dose of methotrexate (50, 100, or 250 mg/kg) at 24h. Additionally, a dose-response for methotrexate at 48 h, and chlorambucil at 24 h were missed using manual scoring. For 1,2-DH, the flow method showed a low level (< 1.4-fold) increase in MN at all doses and times. In contrast, the manual method showed five-seven-fold increases at 24 h, but a < two-fold increase at 48 h in the highest dose only. These data may suggest that the flow method has a greater sensitivity and possibly accuracy than manual scoring. Significant decreases in polychromatic erythrocytes (PCE) were seen using both methods at approximately the same dose for all compounds. However, absolute flow cytometric PCE values were consistently higher than manual. Additional cytotoxicity parameters obtained by the flow method allowed a more complete assessment of cytotoxicity than PCE alone. Furthermore, data reported here combined with improved throughput, shortened data turnaround and reporting times, and possibly better precision due to evaluation of much larger numbers of cells clearly demonstrate the usefulness of flow cytometry method in the routine micronucleus evaluation.

Tomato heat stress protein Hsp16.1-CIII represents a member of a new class of nucleocytoplasmic small heat stress proteins in plants

We describe a new class of plant small heat stress proteins (sHsps) with dominant nuclear localization (Hsp17-CIII). The corresponding proteins in tomato, Arabidopsis, and rice are encoded by unique genes containing a short intron in the beta4-encoding region of the alpha-crystallin domain (ACD). The strong nuclear localization results from a cluster of basic amino acid residues in the loop between beta5 and beta6 of the ACD. Using yeast 2-hybrid tests, analyses of native complexes of the sHsps, and immunofluorescence data, we demonstrate that, in contrast to earlier observations (Kirschner et al 2000), proteins of the sHsp classes CI, CII, and CIII interact with each other, thereby influencing oligomerization state and intracellular localization.

Child maltreatment and the early onset of problem behaviors: can a program of nurse home visitation break the link?

This study investigated the relationship between child maltreatment and the early onset of problem behaviors in the Elmira Nurse Home Visitation Program. Participants were predominantly low-income and unmarried mothers and their first-born children who were randomized either to receive over 2 years of home-visitation services by nurses or to be placed in a comparison group. Data were drawn from a follow-up study that took place when the children were 15 years of age. Results demonstrated that, in the comparison group. child maltreatment was associated with significant increases in the number of early onset problem behaviors reported by the youth. For the youth in the nurse-visited group there was no relationship between maltreatment and early onset problem behaviors. We suggest that this finding was due to the effects of the intervention in reducing the number as well as the developmental timing of the maltreatment incidents. Results suggest that prenatal and infancy home visiting by nurses can moderate the risk of child maltreatment as a predictor of conduct problems and antisocial behavior among children and youth born into at-risk families.

A simplified and reliable HPV testing of archival Papanicolaou-stained cervical smears: application to cervical smears from cancer patients starting with cytologically normal smears

The efficacy of four methods to recover DNA from Papanicolaou (Pap)-stained archival cervical smears for optimal detection of human papillomavirus (HPV) DNA by GP5+/bioGP6+ polymerase chain reaction (PCR) was investigated. Two of the methods were based on proteinase K treatment and two based on treatment with guanidinium thiocyanate (GTC). The quality of the DNA as measured by PCR assays amplifying different sizes of the beta-globin gene appeared to be superior for the GTC-based assays. Using competitive beta-globin PCR assays, one of the GTC-based, assays, provisionally named High Pure PCR Template Preparation (HPPTP) assay, yielded by far the highest quantity of amplifiable DNA. It allowed the recovery of 2.2 x 10(5) to 3 x 10(5) genome equivalents in smears containing 5 x 10(5) to 20 x 10(5) nucleated cells, indicating a mean efficiency of 26% (range of 15-44%). In contrast, the other methods revealed markedly lower efficiencies varying from 1% to 10%. The use of the HPPTP assay as a reliable processing procedure was validated by demonstrating a complete agreement in HPV detection and 93% agreement in HPV typing between 39 archival Pap-stained and paired fresh-frozen cervical smears. This method was applied to 40 archival smears from ten cervical cancer patients (selected from a group of 200 patients) which had a history of 3-6 smears with the first smear being Pap 1 or 2 taken at least 5 years before cancer was diagnosed. The average time period between the first Pap 1/2 smear that contained the same HPV type as in the corresponding carcinoma and diagnosis of cervical cancer was 12.0 +/- 2.9 years. All subsequent smears were invariably positive for the same HPV type which was also found in the cervical cancer biopsy. In conclusion, the HPPTP assay provides a reliable and efficient means to extract DNA from Pap-stained archival cervical smears for the detection of HPV DNA by PCR and would be the method of choice for future HPV analysis of archival Pap-stained cervical smears.

Use of acridine orange in: flow cytometric evaluation of erythropoietic cytotoxicity

Cytotoxic insult to bone marrow frequently impairs the proliferating and maturational abilities of erythroid cells. Typically, a ratio of enucleated, immature polychromatic erythrocytes (PCE) to mature normochromatic erythrocytes (NCE) is used to assess cytotoxicity in the micronucleus (MN) assay. The effects of cyclophosphamide (CP) on PCE/NCE ratio in rat bone marrow and spleen were assessed by a newly developed flow cytometric procedure using glutaraldehyde-fixed, acridine orange (AO)-stained cells, and compared to manual scoring of PCE/NCE in Wright stained slides. Comparison of methods showed that manual and flow cytometric determination of PCE were not statistically different. Several other parameters of cytotoxicity could be simultaneously assessed because the method allowed use of unfractionated whole bone marrow/spleen cell samples. Absolute numbers of total nucleated cells (TNC), a ratio of TNC to total erythrocytes (TE), and determination of RNA content within the PCE population demonstrated dose- and time-dependent effects with CP treatment. Shifts in RNA content were particularly sensitive, correctly identifying all CP-treated from control specimens, even in those samples where PCE/NCE ratio was similar. The AO methodology provided a more rapid, statistically-superior, and thorough approach in the assessment of bone marrow and spleen cytotoxicity than the conventional manual method of scoring PCE/NCE ratio alone.

Use of acridine orange in: flow cytometric assessment of micronuclei induction

The micronucleus assay is a widely accepted method for evaluation of clastogens and aneugens. In the current study, acridine orange (AO) supravital staining was adapted for flow cytometric usage to assess micronucleated cells in rat bone marrow and spleen. Cyclophosphamide was used as a positive control test compound and results were compared to manual scoring in Wright-stained slides. In bone marrow, both manual and flow cytometric methods demonstrated positive dose response-trends for micronucleated polychromatic erythrocytes (MNPCE). Significant elevations in MNPCE were observed at all doses of cyclophosphamide, and comparisons between methods in bone marrow were not statistically different. The flow cytometric method was more sensitive in spleen samples, showing dose- and time-related increases in micronuclei compared with manual scoring. AO proved to be a sensitive discriminator of RNA and DNA, allowing distinct separation of polychromatic erythrocytes (PCE), normochromic erythrocytes (NCE), total nucleated cells (TNC), and micronucleated populations within both PCE and NCE regions. These results support the use of AO-based flow cytometry to provide a rapid and sensitive indicator of micronuclei inducers.

Flow cytometric evaluation of bone marrow differentials in rats with pharmacologically induced hematologic abnormalities

Previously, flow cytometric determination of peroxidase activity, cell size, and reactivity to lymphocyte antibodies were used to produce bone marrow differentials in untreated rats. In the present study, abnormal hematologic profiles were induced with erythropoietin (EPO), recombinant murine stem cell factor (rm-SCF), granulocyte-macrophage stimulating factor (GM-CSF), and cyclophosphamide (CP). Manual and flow cytometric data showed comparable levels of erythroid and myeloid hyperplasia in EPO- and rm-SCF/GM-CSF-treated animals, respectively. In CP-treated animals, flow cytometric data revealed significant decreases in cellularity at concentrations of CP > or = 5 mg/kg. In contrast, 20 mg/kg CP were necessary to induce microscopically apparent hypoplasia in histologic bone sections, showing that the automated methodology was a more sensitive indicator of bone marrow hypocellularity than was the more conventional manual method. Megakaryocyte counts were consistently higher by flow cytometer than by manual counts performed on cytocentrifuge preparations made from the same cell suspensions but were similar to megakaryocyte counts performed on histologic sections of femur, indicating that the automated methodology produced a more accurate reflection of true megakaryocyte numbers. Induction of hematologic abnormalities in the present study showed that manual bone marrow differentials can be replaced with the more efficient and reliable flow cytometric method in most preclinical toxicology studies.

Comparison of flow cytometric and manual bone marrow differentials in Wistar rats

Preclinical drug trials frequently require the evaluation of animal bone marrow, a time-consuming process requiring the skills of a highly trained hematologist. In the present study, a flow cytometric technique was developed that could effectively replace the need for manual bone marrow differentials in rats. Peroxidase activity, measured indirectly with 2'7'-dichlorofluorescein, was coupled with the use of species-specific T- and B-lymphocyte antibodies and cell size to produce a flow cytometric analysis of rat bone marrow. Accurate identification of lymphocyte, proliferating and maturing erythroid and myeloid, and megakaryocyte populations was confirmed by cell sorting. Flow cytometry yielded differentials that were indistinguishable from manual differentials and published reference ranges. Enumeration of lymphocyte numbers with monoclonal markers is a key advantage of flow cytometric differentials because misidentification of lymphocytes in poorly prepared or stained bone marrow smears is a common problem. The most apparent advantage is increased throughput and reproducibility. Operator training for analysis using flow cytometry can be readily accomplished within a few days as opposed to the extensive training required for individuals performing manual bone marrow differentials. This methodology provides a high-volume, rapid, and relatively low-cost tool for the reliable evaluation of rat bone marrow differentials that has been heretofore unavailable.

[Risk factors for squamous epithelial carcinoma of the mouth, the oropharynx, the hypopharynx and the larynx]

This case-control-study, carried out in two University clinics, comprised 200 men (mean age 57.5 +/- 10.8 [range 33-89] years) with squamous epithelioma of the larynx (44.5%), oral cavity (23.5%), oropharynx (24%) or hypopharynx (8%) and 800 controls. Enquiries were directed at social status, life style and occupational exposure to substances such as asbestos, solvents, wood dust and cement. The peak incidence of these cancers was from 50 to 60 years of age. The proportion of unmarried or divorced men among the cancer patients was more than twice as high as in the controls (25.8% vs 11.8%; P less than 0.001). The proportion of cancer patients who had completed technical college or university education was significantly lower than in the controls (9.6% vs 24.4%; P less than 0.001). Tobacco and alcohol consumption by the cancer patients was roughly twice as great as in the controls: the cancer patients admitted to an average cigarette consumption of 43.2 +/- 27.9 pack years as compared with 20.1 +/- 26.7 pack years for the controls (P less than 0.001), and an alcohol intake of 69.2 +/- 58.1 g/d as compared with 29.8 +/- 27.5 g/d for the controls (P less than 0.001). Both these factors--drinking alcohol and smoking cigarettes--acted independently of one another to raise the relative risk of squamous epithelioma of the upper respiratory or digestive tract. The effects of alcohol and tobacco on cancer risk were multiplicative rather than merely additive. Enquiries into diet failed to reveal any clear differences tending to incriminate any particular food. Long-term exposure to cement dust was linked with an increased risk of cancer.

Assignment of a processed mouse Aprt pseudogene to the same chromosome as the functional gene

A novel genetic system has been used to demonstrate that a processed adenine phosphoribosyltransferase (Aprt) pseudogene is located on mouse chromosome 8, which is the same chromosome that carries the functional Aprt gene. A restriction fragment length polymorphism associated with the pseudogene was found to segregate concordantly with chromosome 8 in APRT- mutants of a near-diploid cell line that had lost one copy of the chromosome.