The aim of this study was to assess the main clinical biochemical and immunocytochemical factors influencing survival in 51 patients operated for medullary thyroid carcinoma (MTC). There were 55% of women and 37% of familial cases. Mean age was 43 +/- 3 years. The following survival variables were tested: sex, age, stage, familial disease, Serum Carcino Embryonic Antigen (CEA) and Calcitonin (CT) levels three months postoperatively, intensity of CEA and CT immunostaining, percentage of cells stained for CEA and CT. The actuarial survival rate, including postoperative mortality (N = 1), was studied by uni and multivariate analysis using a Cox model (N = 31). The 5-year survival was 69 +/- 7%. By univariate analysis, stages I or II (p < 0.0001), age of 45 years and less (p < 0.0001), normalized CEA levels (p < 0.006), percentage of CT stained cells greater than 80% (p < 0.04) and weak CT and CEA staining (p < 0.02) were significant predictors of increased survival rates. Age less than 45 and stages I or II were significant prognostic factors of goof survival on multivariate analysis (p < 0.001). We conclude that clinical criteria constitute good survival prognostic factors in patients operated for MTC. The better prognosis of familial cases was probably related to their earlier detection. The prognostic value of immunostaining remains controversial and requires further studies.

Chronic myeloid leukemia (CML) is a clonal myeloproliferative disorder of a stem cell, involving myeloid, erythroid, megacaryocyte, lymphoid B-cells and "natural killer" cells. The hallmark of CML is the Philadelphia (Ph) chromosome which is a shortened chromosome 22 (22q-) resulting from a reciprocal translocation involving chromosome 9 and chromosome 22, designed t (9;22) (q34;q11). This translocation juxtaposes parts of two genes; ABL on chromosome 9 and BCR (breakpoint cluster region) on chromosome 22. Transcription of the BCR/ABL fusion gene results in an hybrid mRNA that is translated into a 210 kDa or 190 kDa protein, depending on the location of the breakpoint in the bcr region. This protein plays a key role in CML: its tyrosine-kinase activity, that differs from the normal ABL product, may be involved in leukemic cell growth. Nonetheless, the loss of the negative cell growth regulation by c-ABL, or BCR/ABL fusion protein interaction with other cellular genes (such as RAS or c-MYC) could also be involved in CML pathophysiology. A better understanding of the molecular mecanisms of CML could lead to specific treatment, such as tyrosine-kinase inhibitors, synthetic oligodeoxynucleotides, or site-specific DNA-binding proteins designed against BCR/ABL oncogenic fusion sequence.

Blau syndrome is a granulomatous disease with dominant autosomal transmission. Skin, joint and ocular manifestations usually appear in childhood.

A certain percentage of cancers are primarily or subsequently resistant to chemetherapeutic agents. Several biological mechanisms are implicated in this phenomenon, including multidrug resistance/P-glycoprotein (mdr1/P-gp), resistance related proteins (P-95 and P-110), multidrug resistance associated protein (P-190), iso-enzymes of gluthatione S-transferase, topo-isomerases, glutathione peroxidase and others. mdr1/P-gp overexpression has been studied in many types of cancer. It represents an inducible, transferable and phylogenetically ancestral biological system. It is expressed at the surface of the cell, and in that way, it participates to several normal functions. The recent introduction of modulators/revertants of mdr1/P-gp may change some concepts in using chemotherapy for cancers. The first step is represented by a better knowledge of the cancers which overexpressed mdr1/P-gp, with determination of the best biological technique, including the gold standards. This allows the clinician to clarify the best impact of such a therapeutic way and to define the criteria of modulator selection. Such criteria includes in vitro selection using a panel of sensitive/resistant cell lines, in vivo tests including transgenic mice, nude or SCID mice, and toxicological studies. Choice of modulated drug is easier and depends on the biological target. For mdr1/P-gp, major drugs included doxorubicin and vinca-alkaloids. Due to the fact that some modulators have an influence on the pharmacokinetic parameters of chemotherapeutic drugs, it is important to verify such parameters. The last choice concerns the strategy of drug development with three levels of action: 1) modulation of clinical chemoresistance, intrinsic or acquired one; 2) modulation of biological resistance; 3) leading to the prevention of the amplification of low levels of chemoresistance. A new therapeutic way is born, which takes care of a dynamic aspect of the tumor, and necessitates a new use of chemotherapy.

Multidrug resistance (MDR) phenotype expression was evaluated retrospectively in 87 patients with acute myeloid leukemia (AML), 69 with de novo AML, ten with relapsed AML and eight with AML secondary to myelodysplastic syndrome (MDS). MDR phenotype, characterized by P-glycoprotein expression (MRK16 monoclonal antibody) and decrease in intracellular daunorubicin (DNR) accumulation was determined using flow cytometry. All patients received chemotherapy including cytosine-arabinoside and anthracycline (daunorubicin, zorubicin, idarubicin) or mitoxantrone, and quinine in ten cases. The predictive value of the MDR phenotype for clinical responsiveness was studied using uni- and multivariate analyses. Univariate analysis showed that DNR accumulation (p < 10(-4)), P-glycoprotein expression (p = 10(-4)) and disease status (de novo versus recurrent AML and acute MDS) (p = 10(-4)) were predictive of clinical responsiveness. The significance of these three parameters was maintained in multivariate analysis. When de novo AML was considered, only DNR accumulation was of predictive value (p < 10(-4)) for complete response to chemotherapy.

Confocal microspectrofluorometry allows the analysis of fluorescent molecules such as anthracylines in isolated living cells. An optical microscope fitted with a phase-contrast 100 X water-immersion objective enables simultaneous observation of the sample, focusing of the laser beam on the selected cell fraction (nucleus) and collection of the fluorescence emitted from the sample. The resulting intranuclear spectra are interpreted according to a quantitative model of the fluorescence spectra of both free and DNA-bound anthracycline. The intranuclear drug concentration can thus be determined. This technique has been applied to blast cells collected in patients with acute leukemia. Leukemic cells are aspirated from bone marrow, separated by Ficoll sedimentation and resuspended in RPMI-1640 containing 10% fetal calf serum and 200 nM tetrahydropyranyl-doxorubicin (THP-DOX). After one hour, 20 cells are analyzed and the mean nuclear drug content is determined (C1). Cells are then resuspended in the same medium but without anthracycline for 3 hours and the mean intranuclear drug concentration is then also determined (C3). From C1 and C3 the retention rate (RR) is calculated. Firstly, the accuracy of the method was checked. In 4 AML patients, two different samples aspirated on the same day were divided into two portions. Thus, two measurements were made on each one (4 values per patient). Coefficients of variation were satisfactory (4, 6, 12, and 12%). Secondly, blast cells collected in patients with AML and ALL at diagnosis or in relapse were studied. P-glycoprotein (P-gp) and CD34 expression was also studied using respectively immunohistochemistry land flow cytometry. Results obtained from the first 21 patients showed that there was no correlation between RR and either P-gp or CD34 expression. This could result from the efflux of THP-DOX by other mechanisms and/or low sensitivity of the staining technique.

Two two-sided cases of conjunctival epidermoid carcinoma and one dysplasia in the same family are reported. The three sisters concerned were teenagers. This familial disease with bilateral localizations in young female patients, is quite rare. Clinical, histological and epidemiological conclusions were based on familial investigation.

Neurofibromatosis type 2 (NF2) is an autosomal dominant disease which predisposes to multiple schwannomas, meningiomas and to a lesser extent, to ependymomas. These tumours have been shown to display frequent loss of chromosome 22. Gene defect causing NF2 has been mapped on chromosome 22. Using positional cloning, we and others recently isolated the gene responsible for NF2. Its product displays strong homology with membrane organizing protein suggesting that this protein, called either Schwannomin or Merlin, could act as a bridge between membrane and cytoskeleton. Alterations of the NF2 gene have been identified in NF2 patients and result usually in a truncated, presumably inactive protein. Analysis of tumoral DNA from sporadic schwannomas and meningiomas demonstrates complete loss of function in many cases, providing evidence that the NF2 gene acts as tumor suppressor gene. As a consequence, genetic presymptomatic diagnosis of at risk individuals for NF2 is now possible.

Several studies have been conducted to identify and determine the nature of genetic anomalies leading to breast cancer. The most frequent genetic anomalies observed in breast cancer are genetic amplification of proto-oncogenes, and mutations and deletions which inactivate suppressor genes. Abnormal protein expression has also been detected. All these modifications of the cell genome could be useful in screening, diagnosis and prognosis of breast cancer, and in the long-term, in developing new therapeutic strategies.

There are two main categories of genes involved in cancer: protoconcogenes and tumor suppressor genes. The development of cancer can require the production of several successive gene accidents within a given cell. Most of these alterations appear to be somatic changes. Only one of these two steps would involve germinal processes and only in hereditary tumors. When altered, these genes, implicated in cell proliferation, differentiation and normal cell death, contribute to the initiation and/or the progression of tumors. Other genes have an indirect effect on the malignant transformation and thus complete the action of oncogenes and suppressor genes at certain stages of cancerogenesis. The genes implicated in individual susceptibility to cancer is an example (genes coding for DNA repair enzymes and for proteins which inactivate exogenous cancerogenenic agents. Others are genes coding for growth factors and angiogenic factors, genes involved in metastatic dissemination including those which code for proteases and adherence proteins, and finally genes affecting chemoresistance.

The state of the art concerning major biological phenomenons of importance for current research on urological cancers is first briefly presented, followed by notes on the more outstanding presentations in this field. These notes are organized in a synthetic fashion, in order to point to the meaning of the hypotheses and findings presented, when taken together, as they pertain to the understanding of the mechanisms at play in urological cancers, as we see them in 1995. Some concepts seem to have now reached a point where we can expect to see some applications in a not so distant future: in prostate cancer, it is confirmed that the machinery of apoptosis is functional even in the hormone-insensitive cells, suggesting that its enhancement might be useful in these often difficult situations; techniques to detect circulating malignant cells, which have been greatly refined (RT-PCR of PSA and PSM), are now extremely sensitive and may prove unvaluable in providing intermediate end points to compare the relative efficacy of treatment regimens in clinical trials; the symposium on prostate cancer screening by PSA dosage was an excellent opportunity to review extensively the data available on this topic, but -as expected- it could not decide on some essential issues; in bladder tumors, data on the expression of adhesion molecules (CD44 variant) are still preliminary, but some provocative observations have been reported (presence on mature ARN, only in bladder cancer cells, of intronic sequences that have not been excised); in renal cell cancer, a considerable amount of knowledge has accumulated on the von Hippel-Lindau gene, a putative anti-oncogene, and work is in progress to define the function of its protein; finally, pathways essential to understanding and treating cancer have been dissected, particularly the apoptosis-proliferation network, and the involvement in it of p53, Waf-1 and the bcl-2 gene family cascade.

Medullary thyroid carcinoma (MTC) is frequently resistant to chemotherapy. Multidrug resistance (MDR) is one of the involved mechanisms. In this work we have studied the MDR1 gene expression in five MTC human cell lines that we have isolated and we have compared this expression to that of normal thyroid tissue. We have also tried to reverse the resistance to doxorubicin with verapamil (VRP) and ciclosporin A (CSA). MDR1 ARNm expression was studied and quantified by polymerase chain reaction (PCR) in normal and pathological thyroid tissues. The doxorubicin-induced cytotoxicity was evaluated with the 3,-4,5 dimethylthiazol-2,5 diphenyl tetrazolium bromide (MTT) test, the neutral red (NR) uptake and with total glutathione (GSH) or intracellular lactate dehydrogenase (LDH) measurements. We found an increase of MDR1 ARNm in MTC as compared with normal tissues. Doxorubicin was cytotoxic after a 48-h coincubation with the cells. Three microM CSA and 10 microM VRP reversed the doxorubicin resistance only after a 48-h coincubation, generally followed with a 24 h-post-incubation. In these conditions, the GSH levels were decreased only by VRP in all the five cell lines. In conclusion, a chemoresistance related to the MDR1 gene overexpression was found in the five human MTC lines tested. VRP and CSA reversed the resistance to doxorubicin in all the MTC cell lines tested.

In acute leukemias evaluating the prognostic factors is one of the main difficulties. At the time of diagnosis, molecular biology highlights the fusion transcripts, the molecular equivalence of certain translocations which are recognised as independent prognostic factors. During the follow-up, the main advantage is in the evaluation of the residual leukemic disease, using in vitro amplification, which is well beyond the limits of detection using traditional technology. Two principal uses are developing: detection of leukemic markers represented by fusion genes and in acute lymphoid leukemias, detection of cloning markers.

Cytogenetic study reveals non random chromosomal abnormalities in 50-80% of patients with acute leukemia. These changes are correlated with morphological [t(15;17) closely connected with FAB M3] and (or) immunological findings [t(1;19) with pre-B/early pre-B ALL]. Karyotype in ALL is an independent prognostic factor. Patients with ALL and hyperdiploidy > 50 chromosomes fared the best as well as patients with AML and inv(16). Conversely the Philadelphia chromosome or t(4;11) in ALL, del5q or trisomy 8 in AML have shown an adverse predictive value. Cytogenetic study is a useful tool to detect relapse and residual disease. Cytogenetic abnormalities have also provided focus for molecular studies of leukemogenesis.

A subset of genetic alterations distinguishes two groups of colon cancers. In the first group instability of microsatellite loci due to a defective DNA mismatch repair system is observed. The second group is characterized by recurrent losses of chromosome regions, frequently associated with hyperploidization. We have developed a technique which enables a fine description of allelic losses in this second group of tumours. The typing of 278 loci in 47 hyperploid colon cancers has provided information for an average of 160 loci per tumour. The high frequency of allelic losses on chromosomes 17, 18 and 5 was confirmed thus validating our methodological approach. Several additional chromosome segments were observed lost in over 40% of the cases, suggesting that tumour suppressor genes may map within these regions. Further technical development should contribute to the identification of these genes.

For almost 100 years, malignant diseases diagnoses have been made by subjective evaluation of morphologic criteria in stained cellular preparations or tissue sections. This diagnosis remains the basis and the first step of any oncological work. Cell quantification by image analysis has only gained scientific but not yet routine application. However it is useful in screening, diagnosis and prognosis of malignant tumors.

There is now substantial evidence that specific human papillomavirus (HPV) types are probably an etiological factor of cervical cancer and its precursors. Virus infection, viral genes expression emerge as necessary but not sufficient for the cells transformation. The E6-E7 oncoproteins of "high risk" (HPV 16-18) papillomaviruses bind specifically, and with high affinity, to cellular tumor suppressor gene products p53 and pRb, in contrast to "low risk" (HPV 6-11) types. This bond disturbs the cell cycle and results in chromosomal instability, aneuploidy and is the probably starting point of the integration of viral DNA to the host genome. These endogenous modifications are reported to the morphological and colposcopical events of cervical intraepithelial neoplasia and seem to be most important in the pathogenesis of cervical cancer precursors lesions and tumor progression.