Phase II trial of afatinib in patients with advanced urothelial carcinoma with genetic alterations in ERBB1-3 (LUX-Bladder 1)

BACKGROUND

Preclinical and early clinical data suggest that the irreversible ErbB family blocker afatinib may be effective in urothelial cancers harbouring ERBB mutations.

METHODS

This open-label, phase II, single-arm trial (LUX-Bladder 1, NCT02780687) assessed the efficacy and safety of second-line afatinib 40 mg/d in patients with metastatic urothelial carcinoma with ERBB1-3 alterations. The primary endpoint was 6-month progression-free survival rate (PFS6) (cohort A); other endpoints included ORR, PFS, OS, DCR and safety (cohorts A and B). Cohort A was planned to have two stages: stage 2 enrolment was based on observed antitumour activity.

RESULTS

Thirty-four patients were enroled into cohort A and eight into cohort B. In cohorts A/B, PFS6 was 11.8%/12.5%, ORR was 5.9%/12.5%, DCR was 50.0%/25.0%, median PFS was 9.8/7.8 weeks and median OS was 30.1/29.6 weeks. Three patients (two ERBB2-amplified [cohort A]; one EGFR-amplified [cohort B]) achieved partial responses. Stage 2 for cohort A did not proceed. All patients experienced adverse events (AEs), most commonly (any/grade 3) diarrhoea (76.2%/9.5%). Two patients (4.8%) discontinued due to AEs and one fatal AE was observed (acute coronary syndrome; not considered treatment-related).

CONCLUSIONS

An exploratory biomarker analysis suggested that basal-squamous tumours and ERBB2 amplification were associated with superior response to afatinib.

CLINICAL TRIAL REGISTRATION

NCT02780687.

Visual Assessment of 2-Dimensional Levels Within 3-Dimensional Pathology Data Sets of Prostate Needle Biopsies Reveals Substantial Spatial Heterogeneity

Prostate cancer prognostication largely relies on visual assessment of a few thinly sectioned biopsy specimens under a microscope to assign a Gleason grade group (GG). Unfortunately, the assigned GG is not always associated with a patient's outcome in part because of the limited sampling of spatially heterogeneous tumors achieved by 2-dimensional histopathology. In this study, open-top light-sheet microscopy was used to obtain 3-dimensional pathology data sets that were assessed by 4 human readers. Intrabiopsy variability was assessed by asking readers to perform Gleason grading of 5 different levels per biopsy for a total of 20 core needle biopsies (ie, 100 total images). Intrabiopsy variability (Cohen κ) was calculated as the worst pairwise agreement in GG between individual levels within each biopsy and found to be 0.34, 0.34, 0.38, and 0.43 for the 4 pathologists. These preliminary results reveal that even within a 1-mm-diameter needle core, GG based on 2-dimensional images can vary dramatically depending on the location within a biopsy being analyzed. We believe that morphologic assessment of whole biopsies in 3 dimension has the potential to enable more reliable and consistent tumor grading.

The influence of treatment sequence in the prognostic value of TMPRSS2-ERG as a biomarker of taxane resistance in castration-resistant prostate cancer

235

Background: TMPRSS2-ERG expression at peripheral blood has been correlated with lower docetaxel benefit. This multicenter study prospectively assessed the role of TMPRSS2-ERG mRNA as a taxane-resistance biomarker in blood and retrospectively in tumors, and explored the impact of prior abiraterone/enzalutamide (A/E) in castration-resistant prostate cancer (CRPC) patients and in vitro. Methods: TMPRSS2-ERG was tested by quantitative reverse-transcription PCR. We included 204 patients (137 blood and 124 tumor samples) treated with taxanes. TMPRSS2-ERG expression was correlated with PSA-progression-free survival (PFS), radiological-PFS (RX-PFS), and overall survival (OS). Independent association with survival was evaluated by multivariate Cox modeling. ERG knockdown, combinatorial and sequential experiments with enzalutamide and docetaxel were performed in VCaP cells. Results: In the multivariate analysis prior A/E (HR: 1.833; P = 0.005) and blood TMPRSS2-ERG (HR: 2, 95%CI; 1.1-3.67; P = 0.018) , were independently associated to lower PSA-PFS. In patients without prior A/E, both blood and tumor TMPRSS2-ERG independently predicted lower PSA-PFS (HR 2.92; P = 0.014 and HR 1.82; P = 0.045, respectively) to taxanes. This was not observed in patients with prior A/E. There was a significant interaction between blood TMPRSS2-ERG detection and prior A/E related to PSA-PFS (P = 0.032) and RX-PFS (P = 0.009). In vitro stable ERG inhibition did not sensitize VCaP cells to docetaxel. Concomitant enzalutamide and taxanes were synergistic, but prior enzalutamide reduced docetaxel cytotoxicity in VCaP cells. Enzalutamide induced neuroendocrine markers and reduced E-cadherin expression. Conclusions: Prior hormone-therapy may influence taxanes response and TMPRSS2-ERG prognostic value. Thus, multiple and sequential biomarkers are needed in CRPC follow-up evaluation.

Phase II trial of afatinib in patients with advanced/metastatic urothelial carcinoma (UC) with genetic alterations in ERBB receptors 1-3 who failed on platinum-based chemotherapy (CT)

TPS540

Background: First-line treatment of patients (pts) with advanced/metastatic UC consists of platinum-based CT, with no well-established subsequent therapy for platinum-refractory disease. Although checkpoint inhibitors have shown promising results recently, targeted agents have generally not demonstrated significant clinical activity in this setting. Around 20% of UC harbor ERBB family genetic alterations, as such it may be a suitable therapeutic target (Knowles, Nat Rev Cancer 2015;15:25–41). The irreversible ERBB family blocker, afatinib, has shown activity in a Phase II trial in a subset of pts with UC who had ERBB2/ERBB3 aberrations (Choudhury, J Clin Oncol 2016;34:2165–71). This Phase II trial will evaluate afatinib in pts with UC molecularly selected for ERBB receptor alterations. Methods: This single-arm trial will assess the efficacy and safety of afatinib in pts with UC harboring ERBB2/ERBB3 mutations or ERBB2 amplification (Cohort A), or EGFR (ERBB1) amplification (Cohort B). Eligible pts are ≥18 years of age with ECOG PS 0–1, histologically confirmed advanced/metastatic UC of the bladder, upper tract or urethra, not amenable to surgery and progressing during or after platinum-based CT, with available archival tissue samples for pre-screening biomarker analysis. Pts will receive oral afatinib 40 mg/day until disease progression or discontinuation. Cohort A is enrolling in two stages, with Stage 2 enrollment based on anti-tumor activity observed. The primary endpoint is progression-free survival (PFS) rate at 6 months; secondary endpoints include objective response rate, PFS, overall survival, disease control rate, duration of response and tumor shrinkage. Trial objectives will be analyzed separately for the two cohorts. Safety and biomarker assessments will also be performed. The trial commenced in June 2016; as of October 4, 2017, 201 samples have been analyzed, with 24.3% and 8% of pts with genetic alterations potentially eligible for inclusion in Cohort A and B, respectively. To date, 12 pts have received study treatment in Cohort A and 6 in Cohort B; recruitment is ongoing. Clinical trial information: NCT02780687.

Substance P autocrine signaling contributes to persistent HER2 activation that drives malignant progression and drug resistance in breast cancer

ERBB receptor transmodulation by heterologous G-protein-coupled receptors (GPCR) generates functional diversity in signal transduction. Tachykinins are neuropeptides and proinflammatory cytokines that promote cell survival and cancer progression by activating several GPCRs. In this work, we found that the pain-associated tachykinin Substance P (SP) contributes to persistent transmodulation of the ERBB receptors, EGFR and HER2, in breast cancer, acting to enhance malignancy and therapeutic resistance. SP and its high-affinity receptor NK-1R were highly expressed in HER2(+) primary breast tumors (relative to the luminal and triple-negative subtypes) and were overall correlated with poor prognosis factors. In breast cancer cell lines and primary cultures derived from breast cancer samples, we found that SP could activate HER2. Conversely, RNA interference-mediated attenuation of NK-1R, or its chemical inhibition, or suppression of overall GPCR-mediated signaling, all strongly decreased steady-state expression of EGFR and HER2, establishing that their basal activity relied upon transdirectional activation by GPCR. Thus, SP exposure affected cellular responses to anti-ERBB therapies. Our work reveals an important oncogenic cooperation between NK-1R and HER2, thereby adding a novel link between inflammation and cancer progression that may be targetable by SP antagonists that have been clinically explored.

Stem cells in prostate cancer

Tumors constitute complex ecosystems with multiple interactions among neoplastic cells displaying various phenotypes and functions and where the tumoral niche is built with an active participation of the host environment that also impacts the malignant progression of the tumor cells. Irrespective of the cell of origin of prostate adenocarcinoma, mounting evidences support the existence of a hierarchy within neoplastic prostate cells that contributes to the heterogeneity of these tumors. At the origin of this hierarchy are small populations of tumor cells with high self-renewal potential and also capable of generating progeny tumor cells that lose self-renewal properties as they acquire more differentiated phenotypes. These cancer stem cells (CSC) depend on active gene networks that confer them with their self-renewal capacity through symmetrical divisions whereas they can also undergo asymmetrical division and differentiation either as stochastic events or in response to environmental cues. Although new experimental evidences indicate that this is can be a reversible process, thus blurring the distinction between CSCs and non-CSCs, the former are considered as the drivers of tumor growth and evolution, and thus a prime target for therapeutic intervention. Of particular importance in prostate cancer, CSCs may constitute the repository population of androgen-insensitive and chemotherapy-resistant tumor cells responsible for castration-resistant and chemotherapy-insensitive tumors, thus their identification and quantification in primary and metastatic neoplasms could play important roles in the management of this disease.

Catastrophic antiphospholipid syndrome triggered by fulminant disseminated herpes simplex infection in a patient with systemic lupus erythematosus

Infections are considered one of the most common causes of morbidity and mortality in patients with systemic lupus erythematosus (SLE), and occasionally can trigger a catastrophic antiphospholipid syndrome (APS). We describe a 22-year-old SLE patient with lupus nephritis under immunosuppressant therapy and asymptomatic carrier of antiphospholipid antibodies, who was admitted with tonsillitis and acute hepatitis, developing multiorgan failure in a few hours. Postmortem examination revealed hepatic necrosis, tonsillitis, pharyngitis and uterine cervicitis caused by herpes simplex virus (HSV) together with microthrombosis in lungs and glomerular arterioles, suggesting the diagnosis of fulminant HSV disseminated infection and catastrophic APS.

Multicentre validation study of nucleic acids extraction from FFPE tissues

In most pathology laboratories worldwide, formalin-fixed paraffin embedded (FFPE) samples are the only tissue specimens available for routine diagnostics. Although commercial kits for diagnostic molecular pathology testing are becoming available, most of the current diagnostic tests are laboratory-based assays. Thus, there is a need for standardized procedures in molecular pathology, starting from the extraction of nucleic acids. To evaluate the current methods for extracting nucleic acids from FFPE tissues, 13 European laboratories, participating to the European FP6 program IMPACTS (www.impactsnetwork.eu), isolated nucleic acids from four diagnostic FFPE tissues using their routine methods, followed by quality assessment. The DNA-extraction protocols ranged from homemade protocols to commercial kits. Except for one homemade protocol, the majority gave comparable results in terms of the quality of the extracted DNA measured by the ability to amplify differently sized control gene fragments by PCR. For array-applications or tests that require an accurately determined DNA-input, we recommend using silica based adsorption columns for DNA recovery. For RNA extractions, the best results were obtained using chromatography column based commercial kits, which resulted in the highest quantity and best assayable RNA. Quality testing using RT-PCR gave successful amplification of 200 bp-250 bp PCR products from most tested tissues. Modifications of the proteinase-K digestion time led to better results, even when commercial kits were applied. The results of the study emphasize the need for quality control of the nucleic acid extracts with standardised methods to prevent false negative results and to allow data comparison among different diagnostic laboratories.

Phase II trial of short-term neoadjuvant docetaxel and complete androgen blockade in high-risk prostate cancer

BACKGROUND

The low probability of curing high-risk prostate cancer (PC) with local therapy suggests the need to study modality of therapeutic approaches. To this end, a prospective phase II trial of neoadjuvant docetaxel (D) and complete androgen blockade (CAB) was carried out in high-risk PC patients. The primary end point was to detect at least 10% of pCRs after chemohormonal treatment.

METHODS

Patients with T1c-T2 clinical stage with prostate-specific antigen (PSA) >20 ng ml(-1) and/or Gleason score >or=7 (4+3) and T3 were included. Treatment consisted of three cycles of D 36 mg m(-2) on days 1, 8 and 15 every 28 days concomitant with CAB, followed by radical prostatectomy (RP).

RESULTS

A total of 57 patients were included. Clinical stage was T1c, 11 patients (19.3%); T2, 30 (52.6%) and T3, 16 (28%) patients. Gleason score was >or=7 (4+3) in 44 (77%) patients and PSA >20 ng ml(-1) in 15 (26%) patients. Treatment was well tolerated with 51 (89.9%) patients completing neoadjuvant therapy together with RP. The rate of pCR was 6% (three patients). Three (6%) additional patients had microscopic residual tumour (near pCR) in prostate specimen. With a median follow-up of 35 months, 18 (31.6%) patients presented PSA relapse.

CONCLUSION

Short-term neoadjuvant D and CAB induced a 6% pCR rate, which is close to what would be expected with ADT alone. The combination was generally well tolerated.

Tumour banking: the Spanish design

In the last decade the technical advances in high throughput techniques to analyze DNA, RNA and proteins have had a potential major impact on prevention, diagnosis, prognosis and treatment of many human diseases. Key pieces in this process, mainly thinking about the future, are tumour banks and tumour bank networks. To face these challenges, diverse suitable models and designs can be developed. The current article presents the development of a nationwide design of tumour banks in Spain based on a network of networks, specially focusing on its harmonization efforts mainly regarding technical procedures, ethical requirements, unified quality control policy and unique sample identification. We also describe our most important goals for the next years. This model does not correspond to a central tumour bank, but to a cooperative and coordinated network of national and regional networks. Independently from the network in which it is included, sample collections reside in their original institution, where it can be used for further clinical diagnosis, teaching and research activities of each independent hospital. The herein described 'network of networks' functional model could be useful for other countries and/or international tumour bank activities.

Activation of nuclear factor-kappa B is linked to resistance to neoadjuvant chemotherapy in breast cancer patients

The nuclear factor (NF)-kappaB system is a promising anticancer target due to its role in oncogenesis and chemoresistance in preclinical models. To provide evidence in a clinical setting on the role of NF-kappaB in breast cancer, we aimed to study the value of basal NF-kappaB/p65 in predicting resistance to neoadjuvant chemotherapy, and to characterise the pharmacodynamic changes in NF-kappaB/p65 expression following chemotherapy in patients with locally advanced breast cancer. Pre- and post-chemotherapy tumour specimens from 51 breast cancer patients treated with anthracycline- and/or taxane-containing neoadjuvant chemotherapy were assayed by immunohistochemistry for NF-kappaB/p65 subcellular expression. We studied NF-kappaB/p65, a well-characterised member of the NF-kappaB family that undergoes nuclear translocation when NF-kappaB is activated. Activation of NF-kappaB (i.e. nuclear NF-kappaB/p65 staining in pre-therapy specimens) was linked to chemoresistance. Patients with NF-kappaB/p65 nuclear staining in pre-treatment samples had a 20% clinical response rate, while patients with undetected nuclear staining had a 91% response rate to chemotherapy (P = 0.002). Notably, four patients achieved a complete histological response and none of them had pre-treatment NF-kappaB/p65 nuclear staining. Moreover, the number of patients with NF-kappaB/p65 activation increased after chemotherapy exposure. It is concluded that NF-kappaB/p65 activation assayed by immunohistochemistry is a predictive factor of resistance to neoadjuvant chemotherapy in breast cancer patients. Moreover, NF-kappaB activation was inducible following chemotherapy in a proportion of breast cancer patients. These novel clinical findings strengthen the rationale for the use of NF-kappaB inhibitors to prevent or overcome chemoresistance in breast cancer.

ATM gene expression is associated with differentiation and angiogenesis in infiltrating breast carcinomas

The product of the ATM gene, mutated in the human genetic disorder ataxia-telangiectasia (A-T) plays a key role in the detection and repair of DNA double-strand breaks. A-T is defined by progressive cerebellar ataxia, telangiectasia, sensitivity to ionising radiation and genomic instability with cancer predisposition. On the other hand, increased angiogenesis is essential for tumor growth and metastasis. The aim of this study was to investigate ATM expression in breast carcinomas and its relationship to neoangiogenesis.

METHODS AND RESULTS

Fifty-two breast tumors from 51 patients, 38 of them with concomitant in situ component (CIS), were analyzed by immunohistochemistry for the expression of ATM. CD34 expression was used for the morphometric evaluation of vasculature. ATM was positive in 1 to 10% of normal epithelial cells. ATM expression was reduced in 55.8% of infiltrating carcinomas, non-reduced in 34.6%, and increased in 9.6%. Expression of ATM in CIS was similar to the infiltrating component in 71% of cases and reduced in 23.7% of them. High-grade ductal infiltrating carcinomas showed lower ATM expression than low-grade ones. Reduced ATM expression also correlated with increased microvascular area.

CONCLUSIONS

Reduced ATM expression in breast carcinomas correlated with tumor differentiation and increased microvascular parameters, supporting its role in neoangiogenesis and tumor progression in breast carcinogenesis.

Dual activation of pathways regulated by steroid receptors and peptide growth factors in primary prostate cancer revealed by Factor Analysis of microarray data

Background

We use an approach based on Factor Analysis to analyze datasets generated for transcriptional profiling. The method groups samples into biologically relevant categories, and enables the identification of genes and pathways most significantly associated to each phenotypic group, while allowing for the participation of a given gene in more than one cluster. Genes assigned to each cluster are used for the detection of pathways predominantly activated in that cluster by finding statistically significant associated GO terms. We tested the approach with a published dataset of microarray experiments in yeast. Upon validation with the yeast dataset, we applied the technique to a prostate cancer dataset.

Results

Two major pathways are shown to be activated in organ-confined, non-metastatic prostate cancer: those regulated by the androgen receptor and by receptor tyrosine kinases. A number of gene markers (HER3, IQGAP2 and POR1) highlighted by the software and related to the later pathway have been validated experimentally a posteriori on independent samples.

Conclusion

Using a new microarray analysis tool followed by a posteriori experimental validation of the results, we have confirmed several putative markers of malignancy associated with peptide growth factor signalling in prostate cancer and revealed others, most notably ERRB3 (HER3). Our study suggest that, in primary prostate cancer, HER3, together or not with HER4, rather than in receptor complexes involving HER2, could play an important role in the biology of these tumors. These results provide new evidence for the role of receptor tyrosine kinases in the establishment and progression of prostate cancer.

Carcinosarcoma of the prostate: two cases with distinctive morphologic and immunohistochemical findings

Carcinosarcomas (CS) of the prostate are very uncommon neoplasms defined by the admixture of malignant epithelial and mesenchymal components. We describe here two new examples of CS in two patients aged 66 and 77 years, the first without previous history of prostate adenocarcinoma and the second with a 5-year history of acinar type prostate adenocarcinoma. The diagnosis of CS was made on the cystoprostatectomy specimen in the first case and transurethral resection in the second case. Both biphasic tumours exhibited papillary areas of ductal differentiation and conventional adenocarcinoma in the epithelial component, as well as malignant fibrous histiocytoma and angiosarcomatous areas in the first case and solid, poorly differentiated epithelial areas with neuroendocrine features in the second case. Immunohistochemistry revealed over-expression of c-erb B2 in the papillary epithelial component of both cases, whereas the solid undifferentiated epithelial areas in the second patient expressed c-kit, CD10 and synaptophysin, thus conforming a very undifferentiated cell population. The angiosarcomatous component of the first case expressed CD31 and CD10. The clinical course of the cases was divergent; the first patient is free of disease after radical surgery and adjuvant therapy and the other died 5 months after the diagnosis of CS, having already developed liver metastases.

A Practical Approach to Intraoperative Evaluation of Sentinel Lymph Node Biopsy in Breast Carcinoma and Review of the Current Methods

BACKGROUND

Sentinel lymph node (SLN) biopsy is increasingly becoming an alternative method for assessing axillary status in breast carcinoma patients. Intraoperative SLN evaluation can potentially select patients for immediate axillary clearance and spare most of them a second surgical procedure. Nevertheless, no standard protocol for intraoperative SLN evaluation has been developed. The aims of this study were to establish the reliability of SLN intraoperative evaluation in breast carcinoma staging, to review the published methods currently used, and to propose a standard protocol.

METHODS

One hundred fifty-two SLNs were collected from 86 patients. Lymphoscintigraphy, blue dye, and gamma camera intraoperative controls were used for localization. Each SLN was sliced 2 mm thick and was intraoperatively evaluated by using the combination of frozen section and imprint cytology. The final examination included standard hematoxylin and eosin staining, and, in case of persistent negativity, further sectioning, including hematoxylin and eosin combined with immunohistochemistry (CAM5.2 cytokeratin), was performed.

RESULTS

The combination of frozen section and imprint cytology for intraoperative SLN evaluation yielded an intraoperative sensitivity of 78% and a specificity of 100%. All macrometastases (>2 mm) were detected during surgery, as were 2 micrometastases. Final examination detected seven more micrometastases, six of which consisted of isolated tumor cells.

CONCLUSIONS

We propose a fast, cost-effective, and accurate procedure for SLN evaluation that is useful for making intraoperative decisions, feasible for most institutions, and reliable because of its high sensitivity (100% for macrometastases) and specificity.

Serial Topoisomerase II Expression in Primary Breast Cancer and Response to Neoadjuvant Anthracycline-Based Chemotherapy

OBJECTIVE

We analyzed the value of topoisomerase IIalpha (Topo II) in predicting the clinical response to anthracycline-based neoadjuvant chemotherapy in breast cancers and the potential changes in Topo II after chemotherapy. In parallel, HER2, which is commonly coexpressed with Topo II, and p53, a modulator of chemotherapy activity, were also analyzed.

METHODS

Forty-one patients with primary breast cancer and treated with neoadjuvant anthracycline-based chemotherapy (FAC or FEC) were included for the present study. Topo II, HER2 and p53 expression were measured by immunohistochemistry in pre and post chemotherapy (at the time of surgery), tumor specimens and the results were correlated with the clinical response.

RESULTS

Topo II was overexpressed in 16 of 41 (31%) tumors before treatment, and this overexpression was significantly associated with clinical response (p = 0.03). HER2 and p53 were unrelated to response. Notably, Topo II overexpression, but not HER2 or p53, was lost in specimens after chemotherapy (p = 0.01).

CONCLUSION

The observed link between Topo II and the clinical response to neoadjuvant anthracycline-based chemotherapy, together with its loss after chemotherapy, implies that Topo II deserves further testing in a prospective setting as a predictive marker.

Low p27 expression predicts biochemical relapse after radical prostatectomy in patients with clinically localised prostate cancer

OBJECTIVE

To assess the prognostic value of p27 protein expression in clinically localised prostate cancer with respect to biochemical recurrence after radical prostatectomy.

PATIENTS AND METHODS

Fifty-two patients (median age 63 years) with prostate cancer were treated by radical prostatectomy in an 18-month period. Data recorded: preoperative PSA level, histopathological Gleason grade, pathological stage and status of surgical margins. p27 expression was evaluated in this group of tumors by immunohistochemistry (positivity was defined as > or = 30% positive cells). Biochemical relapse (BR) was defined by a serum PSA level > or = 0.3 ng/ml.

RESULTS

Twenty-two out of 47 patients (47%) with available follow-up showed a low p27 protein expression. p27 expression did not correlate with pathological stage, Gleason score, serum PSA levels or the status of the surgical margins. Patients presented with BR during the follow-up (risk of BR (RBR) at 36 months: 40%). Patients with low p27 expression showed a higher RBR than the others (RBR 36-month 59% vs. 18%, respectively; p = 0.02). In a multivariate analysis, only p27 along with stage maintained the predictive value for biochemical relapse.

CONCLUSION

p27 expression is a promising prognostic factor in prostate cancer, since it has proved to be a predictor of biochemical relapse.

Galectin-1 accumulation in the ovary carcinoma peritumoral stroma is induced by ovary carcinoma cells and affects both cancer cell proliferation and adhesion to laminin-1 and fibronectin

Galectin-1 (gal-1) is a 14-kDa laminin-binding galectin involved in several biologic events including regulation of cancer cell proliferation and adhesion to the matrix. In this study, we examined gal-1 expression in 30 human epithelial ovary carcinoma samples by Western and Northern blotting and by immunohistochemistry. Gal-1 mRNA levels were increased in more than 95% of the examined ovary carcinoma samples, compared with a wedge resection of a normal ovary. Immunohistochemical analysis of the samples demonstrated gal-1 expression in cancer epithelial cells from 17 of 30 samples, with a cytoplasmic pattern. Gal-1 immunostaining was significantly increased in the stroma associated with carcinoma cells compared with the normal, noninvaded stroma (p = 0.003). This pattern of expression was confirmed by examination of 12 other frozen epithelial ovary carcinomas, using in situ hybridization. Immunohistochemical staining of the specimens demonstrated colocalization of gal-1, laminin-1, and fibronectin. In vitro experiments were conducted to elucidate the potential biologic role of gal-1 in ovarian cancer progression. Gal-1 protein expression and release was detected in AZ364, SK-OV-3, and AZ224, but not in OVCAR-3, AZ419, and AZ382, human ovary carcinoma cell lines. Incubation of 84BR fibroblasts with conditioned media harvested from the ovary carcinoma cell lines induced an increased expression of gal-1 in the cultured fibroblasts in all cases except AZ419 and SK-OV-3. High concentrations of gal-1 (100 micro g/ml) induced significantly decreased cell proliferation in all cell lines, as defined by bromodeoxyuridine incorporation. Additionally, recombinant gal-1 induced a dose-dependent increase in in vitro adhesion of AZ224, SK-OV-3, and AZ382 cells to laminin-1; adhesion to fibronectin was increased by gal-1 in OVCAR-3, AZ224, and SK-OV-3. No effect was observed in the other cases. Our data contribute to define a role for gal-1 during the interactions between human ovary carcinoma cells and host fibroblasts.

The FOXP1 winged helix transcription factor is a novel candidate tumor suppressor gene on chromosome 3p

The JC12 monoclonal antibody recognizes a previously unknown nuclear protein that showed a restricted distribution in normal tonsil and was also overexpressed in a subset of diffuse large B-cell lymphomas. Using this reagent, we expression cloned cDNAs encoding its antigenic target and identified this protein as a novel putative transcription factor, FOXP1. The FOXP1 protein sequence contains predicted domains characteristic of transcription factors, including a winged helix DNA-binding motif, a second potential DNA-binding motif, a C(2)H(2) zinc finger, nuclear localization signals, coiled-coil regions, PEST sequences, and potential transactivation domains. The FOXP1 gene has been mapped to chromosome 3p14.1, a region that commonly shows loss of heterozygosity in a wide range of tumors and which is reported to contain a tumor suppressor gene(s). Using tissue arrays and immunohistochemistry, we demonstrate that both the FOXP1 mRNA and protein are widely expressed in normal tissues. The levels of FOXP1 mRNA were compared in paired normal and tumor tissues (from the same patient) using a tissue array containing cDNAs extracted from 68 samples taken from kidney, breast, prostate, uterus, ovary, cervix, colon, lung, stomach, rectum, small intestine, and from nine cancer cell lines. Differences in FOXP1 mRNA expression between normal and tumor samples were observed in 51% of cases. Most striking was the comparative loss of expression in 73% of colon tumors and comparative overexpression of FOXP1 mRNA in 75% of stomach tumors. Analysis of the FOXP1 mRNA expression in normal tissues (not taken from cancer patients) indicated that loss of FOXP1 expression may occur in some histologically normal tissues adjacent to tumors. Immunohistochemical analysis of FOXP1 protein expression was performed on 128 solid tumors, including 16 renal, 9 breast, 12 lung, 20 colon, 21 stomach, 10 head and neck, 35 prostate, and 5 pancreatic cases. Complete loss of expression, increased expression, and cytoplasmic mislocalization of the predominantly nuclear FOXP1 protein were frequently observed in neoplastic cells. Our study identifies FOXP1 as a new candidate tumor suppressor gene localized to the chromosome 3p14.1 region.

Identification, characterization, and intracellular processing of ADAM-TS12, a novel human disintegrin with a complex structural organization involving multiple thrombospondin-1 repeats

We have identified and cloned a human fetal lung cDNA encoding a new protein of the ADAM-TS family (a disintegrin and metalloproteinase domain, with thrombospondin type-1 modules) that has been called ADAM-TS12. This protein exhibits a domain organization similar to the remaining family members including a propeptide and metalloproteinase-like, disintegrin-like, and cysteine-rich domains. However, the number and organization of the TS repeats is unique with respect to other human ADAM-TSs. A total of eight TS-1 repeats arranged in three groups are present in this novel ADAM-TS. Analysis of intracellular processing of ADAM-TS12 revealed that it is synthesized as a precursor molecule that is first activated by cleavage of the prodomain in a furin-mediated process and subsequently processed into two fragments of different size: a 120-kDa N-terminal proteolytically active fragment containing the metalloproteinase and disintegrin domains, and a 83-kDa C-terminal fragment containing most of the TS-1 repeats. Somatic cell hybrid and radiation hybrid mapping experiments showed that the human ADAM-TS12 gene maps to 5q35, a location that differs from all ADAM genes mapped to date. Northern blot analysis of RNAs from human adult and fetal tissues demonstrated that ADAM-TS12 transcripts are only detected at significant levels in fetal lung but not in any other analyzed tissues. In addition, ADAM-TS12 transcripts were detected in gastric carcinomas and in tumor cell lines from diverse sources, being induced by transforming growth factor-beta in KMST human fibroblasts. These data suggest that ADAM-TS12 may play roles in pulmonary cells during fetal development or in tumor processes through its proteolytic activity or as a molecule potentially involved in regulation of cell adhesion.

BMI-1 gene amplification and overexpression in hematological malignancies occur mainly in mantle cell lymphomas

The BMI-1 gene is a putative oncogene belonging to the Polycomb group family that cooperates with c-myc in the generation of mouse lymphomas and seems to participate in cell cycle regulation and senescence by acting as a transcriptional repressor of the INK4a/ARF locus. The BMI-1 gene has been located on chromosome 10p13, a region involved in chromosomal translocations in infant leukemias, and amplified in occasional non-Hodgkin's lymphomas (NHLs) and solid tumors. To determine the possible alterations of this gene in human malignancies, we have examined 160 lymphoproliferative disorders, 13 myeloid leukemias, and 89 carcinomas by Southern blot analysis and detected BMI-1 gene amplification (3- to 7-fold) in 4 of 36 (11%) mantle cell lymphomas (MCLs) with no alterations in the INK4a/ARF locus. BMI-1 and p16INK4a mRNA and protein expression were also studied by real-time quantitative reverse transcription-PCR and Western blot, respectively, in a subset of NHLs. BMI-1 expression was significantly higher in chronic lymphocytic leukemia and MCL than in follicular lymphoma and large B cell lymphoma. The four tumors with gene amplification showed significantly higher mRNA levels than other MCLs and NHLs with the BMI-1 gene in germline configuration. Five additional MCLs also showed very high mRNA levels without gene amplification. A good correlation between BMI-1 mRNA levels and protein expression was observed in all types of lymphomas. No relationship was detected between BMI-1 and p16INK4a mRNA levels. These findings suggest that BMI-1 gene alterations in human neoplasms are uncommon, but they may contribute to the pathogenesis in a subset of malignant lymphomas, particularly of mantle cell type.

Expression of cyclin D1 and p53 and its correlation with proliferative activity in the spectrum of esophageal carcinomas induced after duodenal content reflux and 2,6-dimethylnitrosomorpholine administration in rats

Alterations in expression of the p53 and cyclin D1 genes have been implicated in the development of esophageal carcinomas in both humans and animal models. We hypothesize that altered expression of cyclin D1 and p53 may be involved in the sequential development of esophageal carcinomas with glandular differentiation induced by the carcinogen, 2,6-dimethylnitrosomorpholine (DMNM) in rats with duodenal content reflux esophagitis. In the present study Sprague-Dawley rats were given DMNM 15 days after performing an esophago-jejunostomy in order to induce chronic duodenal content reflux esophagitis. Expression and localization of p53, cyclin D1 and Ki-67 were examined by immunohistochemical analyses. Twenty of 24 animals developed different types of esophageal carcinomas, including pure squamous carcinoma, adenosquamous carcinoma and pure adenocarcinoma. Undifferentiated basaloid areas were frequently observed in these tumors. Cyclin D1 overexpression was observed in hyperplastic lesions and increased through dysplasia and in undifferentiated areas of infiltrating carcinoma. Cyclin D1 expression coincided with increased Ki-67 expression and decreased along with cell differentiation. The p53 immunohistochemical pattern was parallel to that of cyclin D1, although the percentage of positive cells was usually smaller in all lesions and increased p53 expression started at the dysplastic stage. These findings suggest that overexpression of cyclin D1 may be an early event in DMNM-induced rat esophageal tumorigenesis, causing increased proliferation of esophageal stem cells. Abnormal p53 expression may then be required to promote the development of neoplastic transformation from dysplastic epithelium through invasive phenotype, being more evident in cancer cells with squamous differentiation.

High-grade carcinoma component in epithelial-myoepithelial carcinoma of salivary glands clinicopathological, immunohistochemical and flow-cytometric study of three cases

Three cases of epithelial-myoepithelial carcinoma (EMC) with coexisting areas of high grade carcinoma are reported. In two of the cases there was a previous recurrence, and in all three patients there had been a sudden increase in size before final surgery. The typical ductal and myoepithelial components of EMC showed the usual biphasic pattern and the expected immunophenotypes, with expression of wide spectrum cytokeratins, Cam 5.2 and EMA in the ductal part, and muscle-specific actin, smooth muscle actin, S-100 protein, vimentin and cytokeratins in the myoepithelial component. These areas also had a low mitotic count and low proliferation rate as measured by immunohistochemistry and by flow cytometry. Conversely, areas of high-grade tumour had the features of a large cell carcinoma, with focal mucin secretion in two cases. This high-grade component showed an epithelial immunophenotype in two cases, and was negative for all tested markers in the third one. The mitotic counts and the proliferation rates were much higher in these anaplastic areas. One of the patients died 3 months after treatment; another developed lymph node metastases 1 year later and was alive after 6 years of follow-up. The third patient was alive without evidence of disease 7 months after wide surgical resection of the tumour. The possibility of anaplastic transformation in EMC makes thorough sampling mandatory in this type of neoplasm.

p16(INK4a) gene inactivation by deletions, mutations, and hypermethylation is associated with transformed and aggressive variants of non-Hodgkin's lymphomas

The molecular mechanisms underlying the pathogenesis of aggressive lymphomas and the histological transformation of indolent variants are not well known. To determine the role of p16(INK4a) gene alterations in the pathogenesis of non-Hodgkin's lymphomas (NHLs) and the histological progression of indolent variants, we have analyzed the expression, deletions, and mutations of this gene in a series of 112 NHLs. Hypermethylation of the gene was also examined in a subset of tumors with lack of protein expression but without mutations or deletions of the gene. p16(INK4a) gene alterations were detected in 3 out of 64 (5%) indolent lymphomas but in 16 out of 48 (33%) primary or transformed aggressive variants. In the low-grade tumors, p16(INK4a) alterations were detected in 1 (4%) chronic lymphocytic leukemia (hemizygous missense mutation), 1 (6%) follicular lymphoma (homozygous deletion), and 1 (5%) typical mantle cell lymphoma (homozygous deletion). The two later cases followed an aggressive clinical evolution. In the aggressive tumors, p16(INK4a) gene alterations were observed in 2 (29%) Richter's syndromes (2 homozygous deletions), 3 (33%) transformed follicular lymphomas (1 homozygous deletion and 2 nonsense mutations), 3 (43%) blastoid mantle cell lymphomas (2 homozygous and 1 hemizygous deletions), 5 (28%) de novo large-cell lymphomas (1 homozygous deletion and 4 hypermethylations), 2 lymphoblastic lymphomas (2 homozygous deletions), and 1 of 2 anaplastic large cell lymphomas (hypermethylation). Protein expression was lost in all tumors with p16(INK4a) alterations except in the typical chronic lymphocytic leukemia (CLL) with hemizygous point mutation. Sequential samples of the indolent and transformed phase of three cases showed the presence of p16(INK4a) deletions in the Richter's syndrome but not in the CLL component of two cases, whereas in a follicular lymphoma the deletion was present in both the follicular tumor and in the diffuse large-cell lymphoma. In conclusion, these findings indicate that p16(INK4a) gene alterations are a relatively infrequent phenomenon in NHLs. However, deletions, mutations, and hypermethylation of the gene with loss of protein expression are associated with aggressive tumors and they may also participate in the histological progression of indolent lymphomas.

Differential expression of galectin-1 and galectin-3 during first trimester human embryogenesis

Development of complex organisms requires specific temporospatial differentiation and expression of the correct phenotype through activation of a variety of genes. Galectins are mammalian lectins able to interact with various extracellular matrix glycoconjugates and have been implicated in several biological events including cell attachment, differentiation, apoptosis, embryogenesis, and cancer invasion and metastasis. In this study, we have examined the expression of galectin-1 and galectin-3 during human first trimester embryogenesis using immunohistochemistry and Western blotting. Variable amounts of galectin-1 and galectin-3 were detected in all tissue protein extracts. Galectin-1 expression was demonstrated in the connective tissue and derived tissues such as smooth and striated muscle cells, and in some epithelia, such as in the basal layers of the skin after 14 weeks and in the epithelial cells of the gonads. Galectin-3 was detected mainly in epithelia, such as the skin, epithelial lining of the digestive and respiratory tract, and urothelium and excretory tubes of the kidney, but also in the myocardial cells, in the peripheral and preossifying hypertrophic chondrocytes, and in the notochord and in the liver. Our study constitutes the first demonstration of galectin-1 and galectin-3 during human embryogenesis. The differential expression of these two lectins suggests that they could participate in the complex processes of tissue differentiation.

Deletions and loss of expression of p16INK4a and p21Waf1 genes are associated with aggressive variants of mantle cell lymphomas

Mantle cell lymphoma (MCL) is molecularly characterized by bcl-1 rearrangement and cyclin D1 gene overexpression. Some aggressive variants of MCL have been described with blastic or large cell morphology, higher proliferative activity, and shorter survival. The cyclin-dependent kinase inhibitors (CDKIs) p21Waf1 and p16INK4a have been suggested as candidates for tumor-suppressor genes. To determine the role of p21Waf1 and p16INK4a gene alterations in MCLs, we examined the expression, deletions, and mutations of these genes in a series of 24 MCLs, 18 typical, and 6 aggressive variants. Loss of expression and/or deletions of p21Waf1 and p16INK4a genes were detected in 4 (67%) aggressive MCLs but in none of the typical variants. Two aggressive MCLs showed a loss of p16INK4a expression. These cases showed homozygous deletions of p16INK4a gene by Southern blot analysis. An additional aggressive MCL in which expression could not be examined showed a hemizygous 9p12 deletion. Loss of p21Waf1 expression at both protein and mRNA levels was detected in an additional aggressive MCL. No p21Waf1 gene deletions or mutations were found in this case. The p21Waf1 expression in MCLs was independent of p53 mutations. The two cases with p53 mutations showed p21Waf1 and p16INK4a expression whereas the 4 aggressive MCLs with p16INK4a and p21Waf1 gene alterations had a wild-type p53. p21Waf1 and p16INK4a were expressed at mRNA and protein levels in all typical MCLs examined. No gene deletions or point mutations were found in typical variants. Two typical MCLs showed an anomalous single-stranded conformation polymorphism corresponding to the known polymorphisms at codon 148 of p16INK4a gene and codon 31 of p21Waf1 gene. These findings indicate that p21Waf1 and p16INK4a alterations are rare in typical MCLs but the loss of p21Waf1 and p16INK4a expression, and deletions of p16INK4a gene are associated with aggressive variants of MCLs, and they occur in a subset of tumors with a wild-type p53 gene.

Detection of the bcl-1 rearrangement at the major translocation cluster in frozen and paraffin-embedded tissues of mantle cell lymphomas by polymerase chain reaction

The t(11;14)(q13;q32) translocation and its molecular counterpart bcl-1 rearrangement are highly characteristic of mantle cell lymphomas (MCLs). Most of these translocations occur at the major translocation cluster (MTC) in a tight area that makes this rearrangement identifiable by the polymerase chain reaction (PCR). In this study, the specificity and sensitivity of the PCR technique in the identification of bcl-1 rearrangement and its suitability to amplify the t(11;14) MTC in fixed, paraffin-embedded tissues were analyzed. Genomic DNA was obtained from 21 MCLs and 1 chronic lymphocytic leukemia (CLL) with the t(11;14) translocation. The bcl-1 rearrangement was studied by Southern blot with the MTC, p94PS, and PRAD-1 probes. Polymerase chain reaction was performed using a JH consensus primer and specific primers for chromosome II in the MTC region. bcl-1 rearrangement was identified by Southern blot in the MTC in nine (43%) MCLs and in the p94PS region in the CLL. Polymerase chain reaction analysis of genomic DNA showed that the nine MCLs with MTC rearrangement also had an amplifiable band of the expected size (100%). No amplifiable products were detected in the negative MCLs or in the CLL. The specificity of the PCR products was confirmed by hybridization with an internal MTC oligonucleotide probe. Amplifiable DNA was obtained from the paraffin blocks of 7 cases with MTC rearrangement and 11 negative tumors. bcl-1 rearrangement was detected in this DNA of 6 positive MCLs (86%) by PCR and in none of the negative cases. In conclusion, this study demonstrates that the PCR technique is highly sensitive and specific for the detection of the bcl-1 rearrangement at the MTC. It can be used with both high molecular weight DNA and DNA obtained from formalin-fixed, paraffin-embedded tissues.

Expression of retinoblastoma gene product (pRb) in mantle cell lymphomas. Correlation with cyclin D1 (PRAD1/CCND1) mRNA levels and proliferative activity

Mantle cell lymphomas (MCLs) are molecularly characterized by bcl-1 rearrangement and constant cyclin D1 (PRAD-1/CCND1) gene overexpression. Cyclin D1 is a G1 cyclin that participates in the control of the cell cycle progression by interacting with the retinoblastoma gene product (pRb). Inactivation of the Rb tumor suppressor gene has been implicated in the development of different types of human tumors including some high grade non-Hodgkin's lymphomas. To determine the role of the retinoblastoma gene in the pathogenesis of MCLs and its possible interaction with cyclin D1, pRb expression was examined in 23 MCLs including 17 typical and 6 blastic variants by immunohistochemistry and Western blot. Rb gene structure was studied in 13 cases by Southern blot. Cytogenetic analysis was performed in 5 cases. The results were compared with the cyclin D1 mRNA levels examined by Northern analysis, and the proliferative activity of the tumors was measured by Ki-67 growth fraction and flow cytometry. pRb was expressed in all MCLs. The expression varied from case to case (mean, 14.1% of positive cells; range, 1.3 to 42%) with a significant correlation with the proliferative activity of the tumors (mitotic index r = 0.85; Ki-67 r = 0.7; S phase = 0.73). Blastic variants showed higher numbers of pRb-positive cells (mean, 29%) than the typical cases (10%; P < 0.005) by immunohistochemistry and, concordantly, higher levels of expression by Western blot. In addition, the blastic cases also had an increased expression of the phosphorylated protein. No alterations in Rb gene structure were observed by Southern blot analysis. Cyclin D1 mRNA levels were independent of pRb expression and the proliferative activity of the tumors. These findings suggest that pRb in MCLs is normally regulated in relation to the proliferative activity of the tumors. Cyclin D1 overexpression may play a role in the maintenance of cell proliferation by overcoming the suppressive growth control of pRb.

Spectrum of glandular differentiation in experimental carcinoma of the esophagus induced by 2,6-dimethylnitrosomorpholine under the influence of esophagojejunostomy

To investigate the influence of reflux esophagitis (RE) on the glandular differentiation of carcinomas of the esophagus induced by 2,6-dimethylnitrosomorpholine (2,6-DMNM), a study was carried out using 4 experimental groups and 2 control groups of 8-week-old Sprague-Dawley rats, each consisting of 20 males and 20 females. An esophagojejunostomy (EJ) with gastric preservation was performed in two groups of animals. Fifteen days thereafter the potent esophagotropic carcinogen 2,6-DMNM was subcutaneously injected, once a week for life, at doses of 1/100 and 1/10 of the 50% lethal dose in each group respectively. The result was a spectrum of carcinomatous tumors mainly developing in the lower half of the esophagus, which were thoroughly investigated by serial sectioning, staining for mucins, and in selected cases by electron microscopy. They were classified as follows: 16 pure squamous cell carcinomas (SCC), 5 SCC with focal mucous or glandular differentiation (FGD), 11 pure adenocarcinomas (ADC), and 12 ADC with areas of squamous cell differentiation (SCD). By contrast, in 2 similar experimental groups in which the previous EJ was not performed, 15 animals showed SCC of the pure type, without evidence of mucous or glandular differentiation. No tumors were observed in the two control groups without carcinogen treatment. Of these, the group that underwent EJ showed reflux esophagitis. In conclusion, the tumors of the esophagus induced by 2,6 DMNM under the influence of EJ are not only pure ADC and pure SCC, as we have previously reported, but also intermediate tumors showing either SCC with focal mucous or glandular differentiation (SCC + FGD) or ADC with areas of squamous cell differentiation (ADC + SCD).(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of pancreatic and biliary reflux on the development of esophageal carcinoma

We previously presented an experimental model of Barrett's adenocarcinoma of the esophagus by demonstrating that esophagojejunostomy combined with subcutaneous injection of 2,6-dimethylnitrosomorpholine in Sprague-Dawley rats resulted in development of adenocarcinoma in the distal esophagus. The present study was devised to investigate the influence of pancreatic and biliary duodenal-content reflux on the induction of esophageal carcinoma. Three groups of 8-week-old Sprague-Dawley rats were controls: the first was exposed to pancreatic reflux, the second to biliary reflux, and the third to both. The other three experimental groups were similar except that a 1/100 LD50 dose of 2,6-dimethylnitrosomorpholine was injected subcutaneously weekly, starting on day 15. Carcinoma of the esophagus was induced only in animals receiving the carcinogen after exposure to either pancreatic reflux (3/22, 13%) or pancreatic and biliary reflux (9/27, 33%). Half of the carcinomas were adenocarcinoma and half were squamous cell carcinoma. These findings suggest that under these experimental conditions, in which the carcinogen is used in a low dose, esophageal carcinoma is induced only when pancreatic secretions are present in the duodenal-content reflux. Biliary reflux, however, appears to exert a cocarcinogenic effect when combined with pancreatic secretions. The clinical relevance of these findings needs further evaluation. Conceivably, the elimination of pancreatic and biliary duodenal-content reflux in patients with documented Barrett's mucosa may inhibit the progression from metaplasia to adenocarcinoma.

Pitfalls in mammography screening policy: breast cancer in a 26-year-old patient

A case of invasive ductal carcinoma of the breast diagnosed by mammography in a 26-year-old woman is reported. According to the current recommendations for the early diagnosis of breast cancer, it must be assumed that nonpalpable malignant disease of the breast will be missed in the young asymptomatic population.

Detection of laminin receptor mRNA in human cancer cell lines and colorectal tissues by in situ hybridization

The 67-kd high-affinity laminin receptor (67 LR) is a gene product whose expression appears to be associated with the invasive and metastatic phenotype of a variety of human cancer cells. Northern blot hybridization has been routinely used to quantify the level of 67 LR mRNA from total cellular RNA extracts of homogenized tissue specimens or in vitro grown cell populations. This technique is useful to assess the average expression of the 67 LR mRNA of a particular sample but does not provide information about expression in specific cell types nor about heterogeneity of expression from cell to cell. In this study, we analyzed the expression of 67 LR mRNA in four human cancer cell lines with varying degrees of expression of 67 LR protein (renal cancer A-704, breast carcinoma MCF-7/4 and MCF-7/7, and pancreatic cancer Panc-1) using in situ hybridization performed with 67 LR riboprobes. Total cellular RNA was simultaneously extracted from the cell lines and hybridized on Northern blots with a 67 LR cDNA probe to assess the validity of the mRNA detection by in situ hybridization. Sixty-seven LR mRNA expression was higher in Panc-1 and MCF-7/4 cells than in MCF-7/7 and renal carcinoma A-704. There was a direct correlation (R2 = 0.88) between the in situ hybridization analysis and the mRNA levels detected by Northern blot analysis. The in situ hybridization method showed a heterogeneous expression of the 67 LR mRNA in the four cell lines with different subpopulations of cells showing a range from negative to high levels of the message. Sixteen freshly frozen human colorectal tissues (seven adenocarcinomas, five matched normal mucosae, and four adenomas) were also analyzed by in situ hybridization. The 67 LR mRNA was localized in normal and neoplastic epithelial cells. Adenocarcinoma cells showed a 1.6- to 5-fold higher expression (P < 0.02 according to the Wilcoxon-Mann-Whitney test) than did epithelial colonic cells from normal mucosae or adenomas. The signal tended to be stronger in poorly differentiated carcinomas and carcinomas with metastases than in moderately differentiated and nonmetastatic tumors. We conclude that the high expression of 67 LR mRNA in colorectal tumors is due to an increased production by tumor cells. Furthermore, in situ hybridization is an effective method to detect the expression of LR mRNA in cultured cell lines as well as in frozen tissue sections.

Inverse modulation of steady-state messenger RNA levels of two non-integrin laminin-binding proteins in human colon carcinoma

BACKGROUND

Interactions between cells and the basement membrane glycoprotein laminin are altered during colon cancer progression. Colon carcinoma and normal mucosa cells express a variety of laminin-binding proteins, including the 67-kd laminin receptor (67 LR) and a 31-kd human laminin-binding protein (HLBP31) homologous to the 31-kd human IgE-binding protein/galactoside-binding lectin.

PURPOSE

To investigate whether various laminin-binding proteins are differentially expressed in human colon carcinoma, we studied messenger RNA (mRNA) levels of the 67 LR and HLBP31 in matched tumor and adjacent normal mucosa samples from a series of 21 patients.

METHODS

Total cellular RNA from tumor and normal mucosa was isolated and analyzed by Northern and slot blot hybridization. In addition, HLBP31 protein levels were assessed by the immunoblot technique. Quantitative laminin affinity chromatography was also used to measure the synthesis of HLBP31 protein in five human cancer cell lines.

RESULTS

The steady-state mRNA level of HLBP31 was downregulated (i.e., decreased) in 18 of 21 human colon carcinomas compared with the level in their corresponding normal colonic mucosa. On average, the level of HLBP31 mRNA was decreased 50% +/- 30% (+/- SD) in the colon cancers. The mean ratio of colon cancer HLBP31 mRNA to adjacent normal mucosa HLBP31 mRNA was twofold lower in primary tumors of patients with metastases (0.3 +/- 0.2 SD) than in primary tumors of patients free of metastatic lesions (0.6 +/- 0.2 SD). The differences between the two groups of patients were statistically significant (P less than .05, Wilcoxon-Mann-Whitney test). We have previously shown that the ratio of colon cancer 67 LR mRNA to corresponding normal mucosa 67 LR mRNA was increased in the same patient population. When the two ratios (ratio of cancer to normal HLBP31 mRNA and ratio of cancer to normal 67 LR mRNA) were compared, HLBP31 mRNA/67 LR mRNA was significantly lower (P less than .05) in primary tumors with metastases (mean +/- SD, 0.3 +/- 0.2) than in primary cancers without metastases (mean +/- SD, 0.7 +/- 0.5). The steady-state level of HLBP31 mRNA was directly correlated with the amount of HLBP31 protein in both colon tissue samples and human cancer cell lines.

CONCLUSION

HLBP31 mRNA expression in colon cancer tissues is modulated inversely to that of 67 LR mRNA expression. The down-regulation of HLBP31 appears to be associated with the metastatic capabilities of colon cancer cells.

IMPLICATIONS

Prospective studies on a large cohort should determine if the systematic detection of HLBP31 and 67 LR protein and/or mRNA can be a valuable adjunct in the prognostic evaluation of primary colon cancers.

Immunohistochemical profile of basement membrane proteins and 72 kilodalton type IV collagenase in the implantation placental site. An integrated view

An immunohistochemical study was performed to investigate the interactions between trophoblast and the extracellular matrix in the implantation site of early pregnancies. Two basement membrane-related proteins (type IV collagen and laminin), as well as the expression of the 72 kilodalton type IV collagenase, were studied with affinity-purified antibodies. human placental lactogen, human chorionic gonadotropins, and AE1/AE3 cytokeratins were used to identify the different cell populations involved in the implantation process. All types of trophoblastic cells, from villous cells to the different types of intermediate trophoblast, expressed the 72 kilodalton type IV collagenase. Decidual cells, Hofbauer's cells, villous fibroblasts, and amnion were also positive. Laminin and type IV collagen were expressed in all basement membranes, including large decidual and intermediate trophoblast cells, and the villous stroma. Nitabuch's layer, an acellular degradative zone at the site of initial attachment, showed positivity for type IV collagen. The extracellular matrix in the implantation site seems to be a meshwork of, among other components, laminin and type IV collagen, in which the invading trophoblastic cells are embedded. The invasive capacity of these cells in vivo may be, at least in part, mediated by their type IV collagenolytic activity along with that of the decidual cells, thus regulating the permeability of the extracellular matrix.

A modified Lucas cell for leakage measurement from encapsulated radium sources

A new method to determine the leakage rate from encapsulated radium sources is proposed. The method is based on the principle of enclosing the source to be tested in a hermetically sealed container and measuring the radon radioactivity growth in the container as a function of time. A cylindrical modified Lucas cell, designed and built in our laboratory, is used for measuring the radon which are done by ZnS(Ag) alpha scintillation counting and can be easily compared with existing standard for leak tests. Results obtained show the applicability of the method for leak testing for radon leakage from sealed radium sources.

Mucinous adenocarcinoma of the prostate: histochemical and immunohistochemical studies

Twelve patients with primary mucinous adenocarcinoma of the prostate were included in a clinicopathologic study; criteria included a total tumor volume more than 25% mucinous and single or clustered tumor cells floating in mucin lakes. Patient ages were 57 to 81 years; tumor stages were C (three), D (five), and unknown (four). Bone was the most frequent metastatic site (usually osteoblastic), followed by lymph nodes and lungs. Serum levels of prostatic acid phosphatase and prostate-specific antigen were frequently elevated (five of 10 and three of three measured, respectively). All mucinous adenocarcinomas also contained other histologic patterns: microglandular (four), cribriform (three), comedo (two), solid (two), and hypernephroid (one). Mucinous components composed less than 50% of three tumors, 50% and 75% of six, and more than 75% of three. No tumor contained signet-ring cells. Immunoperoxidase staining was positive for prostatic acid phosphatase and prostate-specific antigen and negative for carcinoembryonic antigen. Treatment was radiation, estrogen, orchiectomy, or a combination. In two of four patients, serum prostatic acid phosphatase levels normalized after therapy. Seven patients died of disease (mean follow-up, 56 months), and five patients are alive with disease (mean, 32.2 months). The proportion of mucinous component did not affect prognosis.