Identification of genes overexpressed in tumors through preferential expression screening in trophoblasts

Early trophoblastic cells share several features with neoplastic cells. Based on that observation, we attempted to identify genes overexpressed in tumors by analyzing genes preferentially expressed in trophoblasts. A subtracted library enriched in complementary DNA from early cytotrophoblasts was constructed, and the expression level of selected recombinants was analyzed on a large panel of normal and tumor tissues. The library was prepared using a polymerase chain reaction-based complementary DNA subtraction method with 6-week amenorrhea cytotrophoblast endoplasmic reticulum-bound RNA as target, and a mixture of complementary DNA prepared from terminal placenta and activated T-lymphocytes as driver. Two rounds of screening were performed to isolate clones preferentially expressed in early placenta. From a total number of recombinant clones estimated at 32,000 in the subtracted library, 594 inserts were analyzed by Southern blot and 21 sequences were isolated as corresponding to genes highly expressed in early placenta. Eleven encoded known molecules, such as carcinoembryonic antigen, human chorionic gonadotropin, and mitochondrial rRNAs. Ten sequences represented novel genes. Northern blot analysis confirmed that most of these genes were preferentially expressed in early trophoblast in comparison to terminal placenta. Three clones that gave detectable hybridization signals on total RNA were extensively studied and were found to be overexpressed in various tumors. Two of these clones, designated B9 and E4, were later identified as corresponding to genes coding for the putative ribosomal protein S18 and the bifunctional enzyme ADE2H1 involved in purine biosynthesis, respectively. Expression of the third clone, E9, was increased up to 10-fold in breast cancer tissues in comparison with normal counterparts. Present results confirm that many genes expressed in the trophoblast are overexpressed in malignant cells. This approach could provide a general targeted method for the identification of genes overexpressed in various neoplastic cell types.

Immunohistochemical study of adrenocortical carcinoma. Predictive value of the D11 monoclonal antibody

BACKGROUND

The diagnosis of adrenocortical carcinoma (ACC) may be difficult with conventional light microscopy, especially when the tumor is nonfunctioning. Until now, no specific adrenocortical tumor marker was available. The current study was undertaken to investigate the interest of the D11 MoAb for the diagnosis and prognosis of ACC.

METHODS

Eighteen adrenocortical carcinomas, 10 primary adrenomedullary tumors, 20 primary hepatocellular carcinomas, 50 primary renal cell carcinomas, 5 primary lung carcinomas, and 18 intraadrenal metastases were analyzed immunohistochemically with the D11 monoclonal antibody. ACC were also evaluated for the expression of other tumor markers, including neuron-specific enolase, chromogranin A, S-100, Leu-7, vimentin, KL1, AE1AE3, and epithelial membrane antigen. Relationships between clinical features and results of immunohistochemistry were also sought.

RESULTS

Nuclear D11 staining appears to be highly specific for normal adrenocortical cells and related tumors. Nuclear D11 positivity was demonstrated in 44% of ACC and was restricted to well-differentiated tumors. No cytoplasmic or nuclear D11 staining was observed in adrenomedullary tumors. D11 reactivity confined to the cytoplasm was found in 5 of 18 adrenal metastases, in all 20 hepatocellular carcinomas tested, in 3 of 5 lung carcinomas, and in 1 of 50 primary renal cell carcinomas. Patients with nuclear D11 immunostaining were initially seen with metastases less often and survived longer than those with no nuclear D11 immunostaining (P < 0.05).

CONCLUSIONS

Nuclear D11 immunoreactivity may help to differentiate ACC from intraadrenal metastases and adrenomedullary tumors. This also selects a group of ACC patients with a more favorable outcome.

Apoptosis induced in Burkitt's lymphoma cells via Gb3/CD77, a glycolipid antigen

Gb3/CD77 is a glycolipid antigen, specifically expressed on two different B-cell populations, Burkitt's lymphoma and a subset of tonsillar B-lymphocytes located in germinal centers, which could be the normal counterpart of Burkitt cells. Both Gb3/CD77(+) populations have recently been shown to enter programmed cell death (apoptosis) readily. Here we show that verotoxin, also called Shiga-like toxin, which is known to bind to the carbohydrate moiety of Gb3/CD77, induces cell death in Gb3/CD77(+) Burkitt's lymphoma cells, not only by inhibiting protein synthesis as classically described but also through an additional mechanism, namely apoptosis. Furthermore a recombinant B-subunit of verotoxin, which carries only the binding property of the holotoxin, also induces apoptosis in Gb3/CD77(+) cells. Gb3/CD77 could thus represent the first example of a glycolipid antigen able to transduce a signal leading to apoptosis.

Numerical aberrations, including trisomy 22 as the sole anomaly, are recurrent in follicular thyroid adenomas

Short-term cultures from 38 follicular thyroid adenomas revealed clonal numerical and/or structural chromosomal changes in 8 tumors, nonclonal changes in 1 tumor, and only normal karyotypes in 29 tumors. Three cases had trisomy 22 as the sole anomaly. Two cases had a combination of trisomies for chromosomes 5, 7, 9, 12, and 16.

Cytogenetic characterization of a new human papillary thyroid carcinoma permanent cell line (GLAG-66)

A new permanent cell line (GLAG-66) has been established from the metastases of a papillary thyroid carcinoma in a male patient. Herein are reported the cytogenetic characteristics of this new cell line, which is tumorigenic in athymic mice. An aneuploid chromosomal pattern was observed (48 chromosomes) with various chromosomal abnormalities. The karyotype was: 48,XY,der(1)t(9;1;9), +der(8)t(1;8),der(9)t(1;9),der(9)t(1;9), +14. This cell line should prove to be of great value in the study of the biology of human papillary thyroid carcinomas.

[Neuroendocrine tumor of the trachea of the intermediate type. Value of its individualization]

Tracheobronchial neuroendocrine tumours can be divided into 4 main groups: typical carcinoid; well-differentiated neuroendocrine carcinoma (atypical carcinoid); neuroendocrine carcinoma of the intermediate type, and small-cell carcinoma. Typical and atypical carcinoids are differentiated tumours, whereas intermediate neuroendocrine tumours and small cell carcinomas are little or not differentiated. Morphological or architectural criteria usually suffice to distinguish between carcinoid tumours and small cell carcinomas. In some cases, however, the neuroendocrine nature of poorly differentiated and non-small cell carcinomas is suggested by morphological criteria, but it can be confirmed only by immunohistochemistry and electron microscopy. Tracheobronchial neuroendocrine tumours of the intermediate type have been studied from a first, well-documented clinical case which demonstrated two important points: the prognosis of these tumours seems to be worse than that of carcinoid tumours, and they favourably respond to chemotherapy. In view of the therapeutic consequences, it is necessary to investigate, by the appropriate techniques, the neuroendocrine nature of these poorly differentiated carcinomas.

Cytogenetic studies on 19 papillary thyroid carcinomas

Short-term cultures from 19 papillary thyroid adenocarcinomas revealed clonal numerical and/or structural chromosomal changes in 13 tumors, nonclonal abnormalities in one tumor, and only normal karyotypes in five tumors. Clonal abnormalities of chromosome 10 were present in three tumors, two of which had the translocation t(7;10)(q35;q21). Numerical abnormalities of chromosome 17 were detected in two tumors.

Two-subunit structure of the human thyrotropin receptor

The extracellular and intracellular domains of the human thyrotropin receptor were expressed in Escherichia coli and the proteins were used to produce monoclonal anti-receptor antibodies. Immunoblot studies and immunoaffinity purification showed that the receptor is composed of two subunits linked by disulfide bridges and probably derived by proteolytic cleavage of a single 90-kDa precursor. The extracellular alpha subunit (hormone binding) had an apparent molecular mass of 53 kDa (35 kDa after deglycosylation with N-glycosidase F). The membrane-spanning beta subunit seemed heterogeneous and had an apparent molecular mass of 33-42 kDa. Human thyroid membranes contained a 2.5- to 3-fold excess of beta subunits over alpha subunits. Immunocytochemistry showed the presence of both subunits in all the follicular thyroid cells, and both subunits were restricted to the basolateral region of the cell membrane.

[Neuroendocrine tumors]

The original classification of neuroendocrine tumours proposed by Pearse was based on a common embryologic origin in the neuroectoderm. This is being replaced by other classifications based on results of modern techniques: secretory granules shown by electron microscopy, neuroendocrine tumour markers (NSE, chromogranin A, NPY ... ) shown by immunocytochemistry and blood measurements. Most endocrine tumours are single and sporadic, but in some patients they are multiple and/or occur as a familial disease such a multiple endocrine neoplasia or other disease, the transmission of which is autosomal dominant. This permits a more reliable classification of tumors, that can be used to determine their prognosis and response to therapy.

Statistical analysis of histomorphological findings in medullary thyroid carcinoma: distinction between the different familial forms of the disease. G.E.T.C. Groupe d'Etude des Tumeurs a Calcitonine

A multifactorial analysis of morphological findings was performed on 153 cases of medullary thyroid carcinoma (MTC). The aim of the study was to utilize histological criteria to discriminate between MTC associated with multiple endocrine neoplasia type 2A (MEN 2A) and that associated with the inherited MTC only syndrome. The presence of fusiform cells associated with several other markers seemed to be more predictive of MEN 2A. A comparison of inherited MTC only and sporadic MTC only showed fusiform cells to be significantly less common in inherited MTC only. These results suggest that the inherited MTC only syndrome is a distinct clinical and morphological entity. Further investigations are needed to confirm the findings and understand its implications.

Primary prostatic Wilms' tumor

The first case of primary Wilms' tumor of the prostatic gland is described. It occurred in a 32-year-old man. Histologically, it consisted of a triphasic tumor; tubular and glomeruloid structures were identified, among prominent blastematous sheets and in an edematous stroma. No teratomatous components were encountered. We propose that this prostatic primary, nonteratomatous Wilms' tumor can arise from persistent, nephrogenic, blastematous rests in the prostate, in relation to the Wolffian duct system.

Tumor-infiltrating CD3- NK cells are more effective than CD3+ T cells in killing autologous melanoma cells

We have studied the phenotype and functional activity of tumor-infiltrating lymphocytes (TIL) derived from eight human melanomas cultured for up to 60 d in the presence of recombinant IL-2. In the early period of the cultures, TIL were predominantly T cells of CD8+ phenotype and contained 10-30% of CD3- cells. Four of the five early TIL cultures tested in a cytotoxicity assay displayed a degree of MHC-unrestricted lysis on a series of autologous and allogenic melanoma cell lines as well as the K562 natural killer-sensitive target. With longer periods of time in culture, all TIL lines showed a decrease in lytic activity that was associated with the loss of CD3- cells. Thus, most of the killing of short-term TIL cultures appeared to be mediated by CD3- natural killer cells, whereas CD3+ T cells were found to be weak anti-tumor effectors. Even though the CD3+ T cells were not cytotoxic on K562 targets, their lytic activity (even weak) against melanoma cells appeared to be non-MHC restricted, and was blocked by anti-CD3 antibodies. In addition, cytotoxicity of the CD3+ TIL cultures was compared to that of a CD3-/NKH1+ cell line purified from peripheral blood. It was found that natural killer cells were much more potent than CD3+ TIL on the melanoma cell lines tested.

gsp mutations in human thyroid tumours

The presence of gsp mutations at codons 201 and 227 in the gene coding for the alpha subunit of the GTP-binding Gs protein which stimulates adenylyl cyclase (AC) has been investigated in 31 samples of differentiated thyroid tumours, which had been previously characterized with respect to their adenylyl cyclase activity (ACA) before and after stimulation by thyroid-stimulating hormone (TSH). Polymerase chain reaction (PCR) amplification of DNA extracted from these tumours, followed by high stringency oligonucleotide probing, enabled the detection of mutations in three samples originating from tumours with high constitutive ACA, which was not significantly further stimulated by TSH. Two mutations were at codon 227 and replaced Gln227 by His or Lys, and one was at codon 201, with the substitution of Arg201 by Ser. Because thyrocytes belong to the subset of differentiated cells which are programmed to proliferate in response to elevated cAMP levels, the gsp mutations observed in some differentiated thyroid carcinomas probably contributed to their tumorigenic phenotype.

Cytogenetic abnormalities in thyroid adenomas

Cytogenetic investigations using short-term cultures are reported in six thyroid adenomas. Clonal and nonclonal numerical chromosomal changes were present in two tumors. In two of the four remaining, nonclonal numerical and structural abnormalities were observed, whereas only normal karyotypes were found in the other two. Chromosome 10 and 17 were involved in several cases, although no common clonal changes could be detected. The present studies show that thyroid adenomas, benign tumors of an endocrine gland, may have chromosomal abnormalities, as described for other benign tumors.

Primary neuroendocrine carcinoma of the skin. Clinicopathologic study of 18 cases

The clinical and pathologic features of primary neuroendocrine carcinoma of the skin in 18 elderly patients are reported. The carcinomas arose in the dermis and subcutaneous tissues, particularly on the head and the upper extremities. One tumor occurred in an irradiated area. Using Gould's clinicopathologic classification, we have found four trabecular types, eleven intermediate cell types, and two small cell types. One tumor could not be classified. Other noteworthy pathologic features were association with invasive squamous cell carcinoma, lentiginous melanocytic hyperplasia, and presence of intratumoral melanocytes. Immunoreactivity for cytokeratins (56 kD), neurofilaments, neuron-specific enolase, and epithelial membrane antigen was observed. The paranuclear globular staining pattern of cytokeratins and neurofilaments was conspicuous. The ultrastructural features revealed paranuclear intermediate filament aggregates (fibrous bodies), neurosecretory granules, and cell junctions. In two metastatic tumors, high levels of catecholamines were found. The trabecular types were characterized by localized disease and a good prognosis. The patients with the small cell types died of distant metastases. Postoperative radiotherapy seemed to reduce the rate of local recurrences.

Study of calcitonin and thyroglobulin gene expression in human mixed follicular and medullary thyroid carcinoma

mRNAs were isolated from 2 patients suffering from a familial form of a rare variant of medullary carcinoma of the thyroid (MTC), called mixed follicular and medullary carcinoma. The presence of calcitonin (CT) and thyroglobulin (Tg) mRNAs was checked by northern and in situ hybridization and compared with immunohistochemical results. In each case, mRNAs hybridizing to probes specific for CT and Tg were detected. Both proteins were quantified by radioimmunoassay determination in tissue extracts. Patient 1 had 20 ng Tg and 68 ng CT per micrograms total protein, and patient 2 had 0.4 ng Tg and 1.7 ng CT per micrograms total protein. Northern analysis showed that mixed carcinoma expressed several species of both CT mRNAs and Tg mRNAs. The main Tg transcripts present in neoplastic cells (8.5 and 4.8 kb for patient 1 and patient 2) were identical to or smaller than those of normal thyroid tissue (8.5 kb). The tumor CT mRNA (1 kb) was identical to that of normal tissue. In situ hybridization confirmed the presence of CT and Tg mRNA in the great majority of tumor cells. Furthermore, the presence of small amounts of organified iodine was evidenced by analytical ion microscopy in 35% of these cells. This raises an important question regarding the histogenesis of this tumor.

Quantification of intracellular calcitonin gene transcripts in human medullary thyroid carcinoma (MTC) by in situ hybridization

The human calcitonin gene generates 2 distinct mature mRNAs by alternative RNA processing, encoding calcitonin (CT) in thyroid C-cells or a neuropeptide (CGRP) in the brain. We evaluated quantitatively by in situ hybridization the expression of the CT gene in tissue section of 5 MTCs (2 sporadic and 3 familial forms). The primary tumor of one MTC was compared to a brain metastasis. In situ hybridization was carried out with tritiated cDNA probes coding for CT and CGRP mRNA. After autoradiography the number of silver grains was counted in 400 cells by computerized analysis of digitized images and expressed as the labelling level (L.L. = grain area/cell area per day of autoradiographic exposure). This was used to calculate the relative abundance per cell of the specific messengers studied, which depends on the autoradiographic efficiency and the specific activity of the probe used. The CT mRNA content was 3.25-6.55 10(-10) micrograms equivalents in the 3 familial forms of MTC and 4.95-9.25 10(-10) micrograms equivalents for the 2 sporadic forms. The levels of CT mRNA in the brain metastasis and in the primary tumor were identical (4.10 10(-10) micrograms equivalents). CGRP mRNA expression was weaker in the sporadic and in the familial thyroid tumors (0.60-1.65 10(-10) micrograms equivalents). The content of mRNA CGRP in the brain metastasis (0.60 10(-10) micrograms equivalents) was lower than that in the primary tumor (1.05 10(-10) micrograms equivalents).(ABSTRACT TRUNCATED AT 250 WORDS)

Hepatic tissue distribution of doxorubicin-loaded nanoparticles after i.v. administration in reticulosarcoma M 5076 metastasis-bearing mice

In our previous studies, doxorubicin-loaded polyisohexylcyanoacrylate nanoparticles have been proven to increase dramatically the antitumoral activity of the cytotoxic agent in metastasis-bearing mice. The experimental model consisted of metastases induced by i.v. inoculation of reticulosarcoma M 5076 cell suspension to C57BL/6 mice. The improved efficacy of the drug was noted in terms of either metastasis count or survival. Therefore, tissue-distribution studies of this drug delivery system within the metastatic liver after i.v. administration were undertaken to gain more insight into the mechanism of action. Doxorubicin measurements in healthy hepatic or neoplastic tissue were carried out together with histological examinations using transmission electron microscopy. These results demonstrated the hepatic tissue to be an efficient reservoir of the drug when it was injected associated with nanoparticles. Accumulation of biodegradable nanoparticles with associated doxorubicin in Kupffer cells created a gradient of drug concentration for a massive and prolonged diffusion of the free drug towards the neoplastic tissue.

Immunoscintigraphy of Hodgkin's disease: in vivo use of radiolabelled monoclonal antibodies derived from Hodgkin cell lines

The Hodgkin associated monoclonal antibody (Mab) HRS-1 reacts with Hodgkin and Reed-Sternberg cells (HR-S) in all HD subtypes. HRS-1 Mab was labelled with radioiodine and injected into 10 patients for immunoscintigraphy (IS). Seven patients were injected with HRS-1 Mab radiolabelled with 131I and three patients were injected with HRS-1 Mab labelled with 123I. A control anti-alpha-fetoprotein (anti-AFP) Mab was radiolabelled with another iodine isotope and was injected simultaneously in five cases. Six out of eight patients with proven HD had a true positive scan (nodal, splenic and bony involvement). Imaging was equivocal or failed in the two other patients. In the last two patients IS imaging was truly negative due to the absence of residual HD in one patient and to an erroneous histological diagnosis of HD in another patient. These results, although preliminary, demonstrate that IS with radioiodine-labelled HRS-1 Mab is feasible and may prove to be informative in the staging of HD.

Presence of mutations in all three ras genes in human thyroid tumors

Polymerase chain reaction (PCR) amplification followed by oligonucleotide probing was used to investigate the presence of ras genes mutations in human thyroid adenomas and carcinomas. The results confirm the frequent occurrence of mutations in all three ras genes in both adenomas and carcinomas, in agreement with the hypothesis that the ras mutations may constitute early steps in thyroid tumorigenesis. No evident correlation between the frequency of ras mutations, the identity of the mutated ras gene, the position affected in the ras gene or the type of mutation and the pathological features is apparent. However, definitive conclusion on this point is precluded because of the small number of tumors examined at the present time.

Immunohistochemical staining of bone marrow biopsies for detection of occult metastasis in breast cancer

Immunohistochemical (IHC) techniques should allow for a greater detection of bone marrow micrometastasis in patients with breast carcinoma. We studied a series of bone marrow (BM) biopsies negative by conventional histologic techniques from 93 patients with breast carcinoma. Prior to this study, twelve BM biopsies, positive by conventional histology, were stained with a panel of monoclonal antibodies (MoAb), directed either against cytokeratin (KL1, AE1-AE3, CAM5-2) or epithelial membrane antigen (EMA, HMFG2). KL1 appeared to be the most sensitive of the markers used in the detection of metastases and is available commercially. It therefore was the only MoAb used with the series of 93 BM biopsies negative by conventional examination. Within this series, among 45 patients clinically suspected of having bone marrow metastasis but with BM biopsies negative by conventional staining, one case showing myelofibrosis stained positive with KL1 demonstrating isolated tumor cells. For the 48 patients without suspicion of bone marrow metastasis at initial diagnosis for breast carcinoma, KL1 revealed no marrow metastasis. Single bone marrow biopsy techniques whether stained by conventional or IHC methods do not appear to be useful tests to detect occult bone marrow metastasis, especially at initial diagnosis of clinically Mo breast carcinoma patients.

Positive anticalcitonin immunoscintigraphy in patients with medullary thyroid carcinoma

A cocktail of three monoclonal F(ab')2 fragments against three distinct epitopes of calcitonin or PDN 21 was labelled with either 111In or 131I. These F(ab')2 fragments, a control 125I-F(ab')2 fragment and 99mTc-pertechnetate were injected into four patients suffering from medullary thyroid carcinoma. Scintigraphy data were processed by energy factor analysis for an optimal separation of images corresponding to each isotope. The best tumor detection was obtained 1-3 days after injection of the 111In-F(ab')2 cocktail which clearly labeled the thyroid tumors in the four patients (smallest tumor detected, 0.6 cm) as well as lymph node and bone metastases. In the liver, positive detection was only successful with the 131I-labeled cocktail. These results were confirmed by counting rates of resected specimens which provided average specificity indices ranging from 3.3 to 13.1. Anticalcitonin antibodies could be particularly useful for immunoscintigraphy detection of residual or recurrent medullary thyroid carcinoma in patients with elevated calcitonin serum level.

Prognostic factors in primary gastrointestinal non-Hodgkin's lymphoma. A multivariate analysis, report of 106 cases, and review of the literature

The authors have reviewed 106 cases of primary gastrointestinal non-Hodgkin's lymphoma (GI-NHL) treated at the Institut Gustave-Roussy (IGR), France, between 1975 and 1986. The occurrence was 55 in the stomach, 26 in the small intestine, ten ileocecal, seven in the large intestine, and eight patients had multiple involvement. Patients were clinically staged according to the Ann Arbor staging system using the modification of Musshoff for Stage IIE. All histologic material of the 106 patients were reviewed and graded according to the Working Formulation (WF) and the Kiel classifications. Most patients received combination chemotherapy as part or all of their primary treatment program (95 patients, 90%). Seventy five patients (71%) had a multimodality treatment. The overall 5-year survival rate was 60%. Sixteen variables were tested by univariate analyses for prognostic influence on survival. Of these, only clinical stage (P less than 0.001), the achievement of initial complete remission (CR) (P less than 0.001), erythrocyte sedimentation rate (ESR) (P = 0.01), mesenteric involvement (P = 0.03), and serosal infiltration (P = 0.05) were significant prognostic factors. Important variables were tested by a multivariate analysis using the Cox model taking into account different treatment modalities. Only three variables entered the regression analysis at a significant level: clinical stage (P = 0.02), surgical resection (P = 0.03), and histologic grade (Kiel) (P = 0.04). When the achievement of initial CR was introduced into the model, it was the most significant variable (P less than 0.001) whereas all other variables became nonsignificant except for the histologic grade (Kiel) (P = 0.004). Based on results of the multivariate analyses we propose two prognostic classifications of patients: one at the initial evaluation depending on clinical stage, surgical resectability, and histologic grade (Kiel); the other at the end of primary treatment depending on the achievement or not of CR and the histologic grade.