Legacy of last millennium timber use on plant cover in Central Europe: Insights from tree rings and pollen

Throughout history, humans have relied on wood for constructions, tool production or as an energy source. How and to what extent these human activities have impacted plant abundance and composition over a long-term perspective is, however, not well known. To address this knowledge gap, we combined 44,239 precisely dated tree-ring samples from economically and ecologically important tree species (spruce, fir, pine, oak) from historical buildings, and pollen-based plant cover estimates using the REVEALS model from 169 records for a total of 34 1° × 1° grid cells for Central Europe. Building activity and REVEALS estimates were compared for the entire study region (4-15°E, 46-51°N), and for low (<500 m asl) and mid/high elevations (≥500 m asl) in 100-year time windows over the period 1150-1850. Spruce and oak were more widely used in wooden constructions, amounting to 35 % and 32 %, respectively, compared to pine and fir. Besides wood properties and species abundance, tree diameters of harvested individuals, being similar for all four species, were found to be the most crucial criterion for timber selection throughout the last millennium. Regarding land use changes, from the 1150-1250's onwards, forest cover generally decreased due to deforestation until 1850, especially at lower elevations, resulting in a more heterogeneous landscape. The period 1650-1750 marks a distinct change in the environmental history of Central Europe; increasing agriculture and intense forest management practices were introduced to meet the high demands of an increasing population and intensifying industrialization, causing a decrease in palynological diversity, especially at low elevations. Likely the characteristic vegetation structure and composition of contemporary landscapes originated from that period. We further show that land use has impacted vegetation composition and diversity at an increasing speed leading to a general homogenization of landscapes through time, highlighting the limited environmental benefits of even-aged plantation forestry.

Modalities of prescription of aromatase inhibitors (AI) in adjuvant therapy for postmenopausal women with HR+ breast cancer: Analysis of daily practices in France

e11619

Background: Aromatase inhibitors (AIs) are widely used as adjuvant therapy for HR+ breast cancer. This survey is an overview of clinical daily practices in France Methods: Multicentric survey conducted in October 2008 by Internet among a sample of 293 physicians specialized in breast cancer management (oncologists, radiotherapists, surgeons) prescribing adjuvant AIs in post-menopausal patients with HR+ breast cancer Results: When started upfront, 87% of physicians expressed that the optimal duration of AIs treatment is 5 years, and 7 % more than 5 years. Nevertheless only, 33% of physicians inform their patients of a total duration of AIs therapy of 5 years, and 66% of a possible adjustment according to the evolution of the scientific knowledge during the five years. AIs are prescribed after the end of chemotherapy by 97% of physicians, after the end of radiotherapy by 83%, and during radiotherapy by 15%. When started after two years of tamoxifen, 71 % of physicians expressed that the optimal duration of AIs treatment is 3 years, 22% 5 years, and 3% more than five years. When started after five years of tamoxifen, 48% of physicians expressed that the optimal duration of AIs treatment is less than three years, 15% 3 years, 15% 5 years, and 2% more than five years. The optimal duration of treatment with aromatase inhibitors is still subject to question for 73% of the physicians interviewed Conclusions: In France, most physicians declared an optimal duration of treatment with aromatase inhibitors in adjuvant setting in HR+ breast cancer in line with guidelines and/or approved indications. However, the optimal duration of treatment is still subject to question for many physicians

No significant financial relationships to disclose.

Oligonucleotide quartz crystal microbalance sensor for the microalgae Alexandrium minutum (Dinophyceae)

We report the immobilization on a gold surface of a 20-base DNA probe labeled with disulfide group and on the selective hybridization with the complementary 20-base DNA strand. The oligonucleotide probe is the complementary strand of a partial sequence of the gene encoding for a large ribosomal RNA sub-unit which is a coding sequence of Alexandrium minutum DNA, a microalgae that produces neurotoxins responsible for paralytic shellfish poisoning on European and Asian coasts. The kinetics of DNA probe immobilization and hybridization were monitored in situ by using a 27 MHz quartz crystal microbalance under controlled hydrodynamic conditions. The frequency of the setup is stable to within a few hertz, corresponding to the nanogram scale, for 3h and makes it possible to follow frequency change from immobilization of the probe to hybridization of the complementary DNA target. This setup constitutes a biosensor, which is sensitive and selective, and the hybridization ratio between hybridized complementary DNA and immobilized DNA probes is 47%.

Extensive tissue-specific variation of allelic methylation in the Igf2 gene during mouse fetal development: relation to expression and imprinting

The imprinted Igf2 gene is active only on the paternal allele in most tissues. Its imprinting involves a cis-acting imprinting-control region (ICR) located upstream of the neighboring and maternally expressed H19 gene. It is thought that differential methylation of the parental alleles at the ICR is crucial for parental imprinting of both genes. Differentially methylated regions (DMRs) have also been identified within the Igf2 gene and their differential methylation is thought to be established during early development. To gain further insight into the function of these DMRs, we performed a quantitative analysis of their allelic methylation levels in different tissues during fetal development and the postnatal period in the mouse. Surprisingly, we found that the methylation levels of Igf2 DMRs vary extensively during fetal development, mostly on the expressed paternal allele. In particular, in skeletal muscle, differential allelic methylation in both DMR 1 and DMR 2 occurs only after birth, whereas correct paternal monoallelic expression is always observed, including in the embryonic stages. This suggests that differential methylation in the DMR 1 and DMR 2 of the Igf2 gene is dispensable for its imprinting in skeletal muscle. Furthermore, progressive methylation of the Igf2 paternal allele appears to be correlated with concomitant postnatal down-regulation and silencing of the gene. We discuss possible relations between Igf2 allelic methylation and expression during fetal development.

Bone-targeted Src SH2 inhibitors block Src cellular activity and osteoclast-mediated resorption

Src, a nonreceptor tyrosine kinase, is an important regulator of osteoclast-mediated resorption. We have investigated whether compounds that bind to the Src SH2 domain inhibit Src activity in cells and decrease osteoclast-mediated resorption. Compounds were examined for binding to the Src SH2 domain in vitro using a fluorescence polarization binding assay. Experiments were carried out with compounds demonstrating in vitro binding activity (nmol/L range) to determine if they inhibit Src SH2 binding and Src function in cells, demonstrate blockade of Src signaling, and lack cellular toxicity. Cell-based assays included: (1) a mammalian two-hybrid assay; (2) morphological reversion and growth inhibition of cSrcY527F-transformed cells; and (3) inhibition of cortactin phosphorylation in csk-/- cells. The Src SH2 binding compounds inhibit Src activity in all three of these mechanism-based assays. The compounds described were synthesized to contain nonhydrolyzable phosphotyrosine mimics that bind to bone. These compounds were further tested and found to inhibit rabbit osteoclast-mediated resorption of dentine. These results indicate that compounds that bind to the Src SH2 domain can inhibit Src activity in cells and inhibit osteoclast-mediated resorption.

H19 gene expression is up-regulated exclusively by stabilization of the RNA during muscle cell differentiation

H19 is a paternally imprinted gene whose expression produces a 2.4 kb RNA in most tissues during development and in mammalian myoblastic cell lines upon differentiation. Deletion of the active maternal allele of H19 and its flanking regions in the mouse leads to biallelic methylation and loss of imprinting of the neighbouring Igf2 gene. The function of H19 RNA remains unknown and, although polysome-associated, the absence of a conserved open reading frame suggests that it does not encode a protein product. We describe a novel post-transcriptional regulation of H19 gene expression which, in spite of this lack of coding capacity, is dependent on translational activity. We show that stabilization of the RNA is solely responsible for its accumulation during in vitro muscle cell differentiation. This conclusion is based on the finding that inhibition of protein synthesis results in a dramatic destabilization of H19 RNA in proliferating mouse C2C12 myoblastic cells but not in differentiated cells, and on run-on experiments which showed that the rate of transcription of H19 RNA remains constant during muscle cell differentiation. This mechanism could also be involved in H19 gene expression during mouse development in addition to its transcriptional activation which we have shown to occur.

Cloning and over-expression in Escherichia coli of the gene encoding NADPH group III alcohol dehydrogenase from Thermococcus hydrothermalis. Characterization and comparison of the native and the recombinant enzymes

A NADP-dependent group III alcohol dehydrogenase (ADH) was purified from the hyperthermophilic strictly anaerobic archaeon Thermococcus hydrothermalis, which grows at an optimum temperature of 85 degrees C and an optimum pH of 6. The gene encoding this enzyme was cloned, sequenced, and over-expressed in Escherichia coli. The recombinant enzyme was purified, characterized and compared with the native form of the enzyme. The enzyme structure is pH-dependent, being a 197-kDa tetramer (subunit of 45 kDa) at pH 10.5, the pH optimum for alcohol oxidation, and a 80.5-kDa dimer at pH 7.5, the pH optimum for aldehyde reduction. The kinetic parameters of the enzyme show that the affinity of the enzyme is greater for the aldehyde substrate and NADPH cofactor, suggesting that the dimeric form of the enzyme is probably the active form in vivo. The ADH of T. hydrothermalis oxidizes a series of primary aliphatic and aromatic alcohols preferentially from C2 to C8 but is also active towards methanol and glycerol and stereospecific for monoterpenes. T. hydrothermalis ADH is the first Thermococcale ADH to be cloned and overproduced in a mesophilic heterologous expression system, and the recombinant and the native forms have identical main characteristics.

DNA topoisomerase I: customs officer at the border between DNA and RNA worlds?

DNA topoisomerase I is required for the normal development of multicellular organisms, probably because it plays a role in controlling gene activity, in addition to its function in relieving tortional stress during DNA replication and transcription. The discovery of DNA topoisomerase I as a specific kinase that phosphorylates serine-arginine rich (SR) splicing factors may provide new insights into their precise function in regulating gene expression. It is clear that the splicing factors phosphorylated by DNA topoisomerase I can modulate gene expression by changing the splicing pattern of structural genes. Studies of the splicing mechanism suggest that the phosphorylation of serine residues of SR proteins contribute to their activity. As this phosphorylation can be accomplished by several kinases, it remains to be determined whether phosphorylation by DNA topoisomerase I protein kinase is the limiting step in regulating this process. The availability of specific inhibitors of DNA topoisomerase I, structurally related to the alkaloid camptothecin, have made it possible to address this question experimentally. These inhibitors, which hold great promise as antineoplastic drugs, lead to specific inhibition of SR protein phosphorylation in cultured cells. This observation will hopefully lead to improved understanding of the mechanism by which these drugs act at cellular level.

Thermosipho melanesiensis sp. nov., a new thermophilic anaerobic bacterium belonging to the order Thermotogales, isolated from deep-sea hydrothermal vents in the southwestern Pacific Ocean

A new thermophilic, anaerobic rod-shaped bacterium, strain BI429T was isolated from the gills of a deep-sea vent hydrothermal mussel, Bathymodiolus brevior, from the Lau Basin (Southwestern Pacific Ocean). Phenotypically, this isolate exhibited characteristics similar to those described for members of the order Thermotogales. This organism was identified as a member of the genus Thermosipho on the basis of the presence of the typical outer sheath-like structure (toga), its 16S rRNA sequence, and its ability to grow on carbohydrates (sucrose, starch, glucose, maltose, lactose, cellobiose, and galactose). The cells of this organism were gram negative and rod shaped and generally occurred singly or in pairs, rarely occurring as chains with a maximum of five rods. At the optimum temperature for growth (70 degrees C), optimum pH (6.5), and optimum salinity (30 g of NaCl per liter), the doubling time was 100 min. In spite of the high percentage of similarity of its 16S rRNA sequence with that of Thermosipho africanus (98.6%), the weak level of DNA-DNA reassociation with this strain (2%) and particular physiological characteristics allowed us to differentiate this new organism from the sole species of the genus Thermosipho previously described (T. africanus). On the basis of these observations, we propose that the new organism should be described as a new species, Thermosipho melanesiensis. The type strain of T. melanesiensis is BI429.

Docetaxel in combination chemotherapy for metastatic breast cancer

Due to its novel mechanism of action, docetaxel has significant in vitro activity against a variety of solid tumors, including breast cancer. In phase II clinical trials, docetaxel 100 mg/m2 every 3 weeks has shown substantial single-agent activity in patients with both previously untreated and heavily pretreated metastatic breast cancer. As single-agent chemotherapy is rarely curative in this setting, docetaxel has been combined with other anticancer agents with proven efficacy against breast cancer (doxorubicin, vinorelbine, fluorouracil, cyclophosphamide, cisplatin, and doxorubicin plus cyclophosphamide) in an attempt to increase efficacy and prolong patient survival. The aims of these phase I dose-finding studies were to define the maximum tolerated dose, the dose-limiting toxicity, the recommended dose, and the safety profile of each combination. All patients had previously untreated metastatic breast cancer. Each study followed a dose-escalation design; patients were initially assigned to the lowest dose level, with at least three patients treated at each level before enrolling patients at the next level. All patients received corticosteroid-based premedication, but granulocyte colony-stimulating factor was not routinely used. The docetaxel/doxorubicin and docetaxel/ vinorelbine studies have been recently completed; in both studies, the dose-limiting toxicity was neutropenia. Other adverse events were generally mild. No significant cardiotoxicity (with docetaxel/doxorubicin) or neurotoxicity (with docetaxel/vinorelbine) was observed, and no patients discontinued treatment because of fluid retention. Both combinations are well tolerated without granulocyte colony-stimulating factor support. The recommended dose for docetaxel/doxorubicin in phase II studies is either 75/50 or 60/60 mg/m2 administered on day 1 every 3 weeks; impressive response rates of 90% and 66%, respectively, were achieved with these dose levels. The recommended dose for docetaxel/vinorelbine is docetaxel 85 mg/m2 on day 1 and vinorelbine 20 mg/m2 on days 1 and 5, repeated every 3 weeks; the efficacy of this combination is still being evaluated, but preliminary results are promising. For both combinations, the time to disease progression and median response duration were not available at the time of this report. Combination studies with fluorouracil, cisplatin, and cyclophosphamide, and a study of sequential administration with doxorubicin + cyclophosphamide, are ongoing. Interim results indicate that these docetaxel-based combinations have acceptable safety profiles and encouraging levels of antitumor activity. The full results of these studies will help to elucidate the potential contribution of docetaxel-based combination chemotherapy to the management of metastatic breast cancer.

Thermococcus hydrothermalis sp. nov., a new hyperthermophilic archaeon isolated from a deep-sea hydrothermal vent

An extremely thermophilic archaeon, strain AL662T, was isolated from a deep-sea hydrothermal vent located on the East Pacific Rise at a latitude of 21 degrees N. This strain is a strictly anaerobic coccus, and its cells range from 0.8 to 2 microns in diameter. The optimum temperature, pH, and Sea Salt concentration for growth are 85 degrees C, 6, and 20 to 40 g/liter, respectively. Strain AL662T grows preferentially on proteolysis products, on a mixture of 20 amino acids, and on maltose in the presence of elemental sulfur. The membrane lipids consist of di- and tetraether glycerol lipids. The DNA G+C content is 58 mol%. Sequencing of the 16S rRNA gene showed that strain AL662T belongs to the genus Thermococcus. On the basis of hybridization results, we propose that this strain should be placed in a new species, Thermococcus hydrothermalis.

[Endometrial cancer: progress in the evaluation of locoregional extension by imaging techniques]

In the evaluation of loco regional extension, MRI and ultrasound provide highly valuable information, with respect to the invasion of deep myometrium, which determines prognosis, being highly similar for the two techniques. This gives ultrasound techniques a role of primary intention for reasons of public health economics. MRI, however, improves the work-up of other types of loco regional extension, and CT scan remains an indispensable tool for evaluating overall lymph node involvement and visceral extension.

Involvement of U1 small nuclear ribonucleoproteins (snRNP) in 5' splice site-U1 snRNP interaction

U1 small nuclear ribonucleoprotein (snRNP) is an important ribonucleoprotein involved early in the spliceosome formation to commit pre-mRNAs to the splicing pathway. We have determined the association and dissociation kinetics of the 5' splice site-U1 snRNP interaction using purified U1 snRNP and a short RNA oligonucleotide comprising the 5' splice site (5'-SS) consensus sequence of pre-mRNAs (5'-SS RNA oligo). The association is rapid, does not require ATP, and is almost irreversible. Surprisingly, oligonucleotide-directed cleavage of the U1 small nuclear RNA (snRNA) 5' end sequence with RNase H has no significant effect on the rate of association of the 5'-SS RNA oligo, but it does lead to rapid dissociation. This provides evidence that U1-specific snRNP proteins are critical for the 5' splice site recognition while base pairing ensures the stability of the interaction. The recognition of the 5' splice site by U1 snRNP does not result from the individual action of one or more proteins but rather from their organization around U1 snRNA. A consequence of this organization is that the U1-C protein makes direct contacts with the site, as it becomes cross-linked to the RNA oligo upon exposition of the reactions to shortwave UV light.

Virtual tracheo-bronchial endoscopy: educational and diagnostic value

The use of Helical CT significantly improves image quality of examinations in a number of clinical settings. It is particularly suited to the study of the tracheo-bronchial tree as a result of new ways of image processing (developed by GEMS research) which can produce virtual endoscopic images without the use of an endoscope. We present our initial anatamo-radiological findings and their educational value as well as our thoughts on potential future clinical applications.

Specific phosphorylation of SR proteins by mammalian DNA topoisomerase I

Several metazoan splicing factors are characterized by ribonucleoprotein (RNP) consensus sequences and arginine-serine repeats (RS domain) which are essential for their function in splicing. These include members of the SR-protein family (SC35, SF2/ASF), the U1 small nuclear (sn) RNP protein (U1-70K) and the U2 snRNP auxiliary factor (U2AF). SR proteins are phosphorylated in vivo and the phosphorylation state of U1-70K's RS domain influences its splicing activity. Here we report the purification of a protein kinase that is specific for SR proteins and show that it is DNA topoisomerase I. This enzyme lacks a canonical ATP-binding motif but binds ATP with a dissociation constant of 50 nM. Camptothecin and derivatives, known to be specific inhibitors of DNA topoisomerase I, strongly inhibit the kinase activity in the presence of DNA and affect the phosphorylation state of SR proteins. Thus, DNA topoisomerase I may well be one of the SR protein kinases operating in vivo.

Structural features of U6 snRNA and dynamic interactions with other spliceosomal components leading to pre-mRNA splicing

In the spliceosome, the pre-mRNA, U2 and U6 snRNAs fold into a catalytic structure exhibiting striking similarities with domain V and VI of group II introns. Building of this tripartite structure implies that an evolutionary conserved base pairing between U4 and U6 snRNAs should be disrupted to allow potentially U6 catalytic residue to interact with U2 snRNAs and the pre-mRNA. The steps leading to U4/U6 disruption have been recently discovered and have been shown to involve a modification of the 3' end of U6 snRNA and the hnRNP C protein.

Fotemustine, dacarbazine, vindesine combination chemotherapy in advanced malignant melanoma: a phase II study of 43 patients

Fotemustine and dacarbazine constitute the most active single chemotherapeutic agents in the treatment of melanoma. In this phase II study we evaluated the activity and toxicity of a combination of fotemustine, dacarbazine and vindesine as a means of increasing response rate and survival time. Between September 1989 and November 1993, 43 patients with advanced melanoma were treated with a combination of 100 mg/m2 fotemustine on days 1 and 8, 250 mg/m2 dacarbazine on days 15 and 16 and 2 mg/m2 vindesine on days 15 and 16 as induction treatment. After a 5-week rest period, the patients exhibiting a response or stable disease received the same drugs administered once every 28 days as maintenance therapy until either progression or toxicity was observed. Among 41 evaluable patients, there were six complete responses and eight partial responses. The overall response rate was 32% (95% confidence interval: 18-46%), with 8 months median duration of response. Median survival time was 10 months. This regimen was well tolerated. From this large phase II study, we conclude that such a combination is active against advanced malignant melanoma and seems to be more effective than fotemustine or dacarbazine used alone, especially on visceral metastatic sites.

Disruption of base-paired U4.U6 small nuclear RNAs induced by mammalian heterogeneous nuclear ribonucleoprotein C protein

Due to 3' end modifications, mammalian U6 small nuclear RNA (snRNA) is heterogeneous in size. The major form terminates with five U residues and a 2',3'-cyclic phosphate, but multiple RNAs containing up to 12 U residues have a 3'-OH end. They are labeled in the presence of [alpha-32P]UTP by the terminal uridylyl transferase activity present in HeLa cell nuclear extracts. That these forms all enter the U6 snRNA-containing particles, U4.U6, U4.U5.U6, and the spliceosome, has been demonstrated previously. Here, we report an interaction between the heterogeneous nuclear ribonucleoprotein (hnRNP) C protein, an abundant nuclear pre-mRNA binding protein, and the U6 snRNAs that have the longest uridylate stretches. This U6 snRNA subset is free of any one of the other snRNPs, since anti-Sm antibodies failed to immunoprecipitate hnRNP C protein. Furthermore, isolated U4.U6 snRNPs containing U6 snRNAs with long oligouridylate stretches are disrupted upon binding of hnRNP C protein either purified from HeLa cells or produced as recombinant protein from Escherichia coli. In view of these data and our previous proposal that the U6 snRNA active in splicing has 3'-OH end, we discuss a model where the hnRNP C protein has a decisive function in the catalytic activation of the spliceosome by allowing the release of U4 snRNP.

High-dose ifosfamide: circumvention of resistance to standard-dose ifosfamide in advanced soft tissue sarcomas

PURPOSE

The study was designed to assess the toxicity and activity of high-dose ifosfamide (HDI) administered by continuous infusion at a dose of 4 g/m2/d over 3 days every 4 weeks in adult patients with advanced soft tissue sarcomas (ASTS) pretreated with doxorubicin and/or a standard-dose ifosfamide (SDI)-containing regimen.

PATIENTS AND METHODS

Between January 1991 and November 1993, 40 patients with progressive ASTS were entered onto the study. Twenty-eight patients had been pretreated with a multidrug regimen that contained SDI and were classified as follows: SDI-refractory (n = 21), SDI-resistant (n = 2), and indeterminate SDI-sensitive (n = 5). Patients were treated until progression or major toxicity.

RESULTS

One hundred forty-seven cycles of HDI were administered. Neutropenia was dose-limiting, with 100% of patients experiencing grade 3 to 4 toxicity and 12 admissions for febrile neutropenia (30% of patients). Neurotoxicity (17% of patients) was significantly associated with acute renal failure (n = 4) (P < .001), grade 4 thrombocytopenia (P < .01) and febrile neutropenia (P = .048). Chronic renal toxicity (n = 4) was significantly associated with retroperitoneal masses and/or prior nephrectomy (P = .008). Partial responses (PRs) were observed in 12 of 36 assessable patients (33%) and eight patients (22%) experienced disease stabilization. All but one response occurred in patients pretreated with SDI, with five PRs among SDI-refractory patients. Leiomyosarcomas appear resistant to HDI. The median response duration was 8 months (range, 6 to 13+) and the median overall survival time was 12 months.

CONCLUSION

The activity of HDI in these pretreated ASTS patients and the apparent circumvention of SDI resistance suggest a real dose-response relationship for ifosfamide and deserve further evaluation. Although toxic, this treatment appears feasible and manageable using routine clinical support. Since prophylaxis of ifosfamide-induced renal damage remains unknown, frequent monitoring of renal and tubular functions during therapy is highly recommended.

Phase II trial of vinorelbine/doxorubicin as first-line therapy of advanced breast cancer

PURPOSE

The study investigated the therapeutic effects of a combination of Navelbine (vinorelbine or 5'noranhydrovinblastine; Pierre Fabre Médicament, Boulogne, France) and doxorubicin in women who had received no prior chemotherapy for locally advanced or metastatic breast cancer.

PATIENTS AND METHODS

Ninety-seven patients with progressive and assessable advanced or metastatic breast cancer who had received no prior chemotherapy except in an adjuvant setting were entered onto the study. Eighty-nine patients were assessable for toxicity and response by World Health Organization (WHO) criteria; the other eight patients were excluded because they did not meet entry criteria or because of protocol violations. Navelbine was administered at 25 mg/m2 by 30-minute intravenous (IV) infusion on days 1 and 8, and doxorubicin at 50 mg/m2 by slow IV infusion on day 1, with each course repeated at 3-week intervals. Patients were treated for a maximum of 11 cycles or until progression or major toxicity.

RESULTS

Objective responses were observed in 66 of 89 assessable patients (74%; 95% confidence interval, 63% to 85%). There were nineteen (21%) complete responses (CRs) and 47 (53%) partial responses (PRs). In addition, 20 patients (22.5%) had stable disease and three (3.5%) progressed while on treatment. Responses were observed at all sites of metastatic disease. Forty-one of 58 patients with visceral disease responded (71%) and 25 of 31 with soft tissue and bone disease experienced an objective response (81%). The median duration of response was 12 months (range, 2.4 to 40.5), and the median overall survival was 27.5 months (range, 4 to 46). Neutropenia was dose-limiting, with 36 patients (41%) experiencing grade 3 or 4 toxicity. Of 727 cycles administered, there were 20 admissions (3%) for treatment of febrile neutropenia, involving 14 of 89 patients (16%). Treatment-related cardiotoxicity at grade 2 to 4 was experienced by 10% of patients and necessitated the interruption of treatment in 1.5% of cycles. Other side effects were uncommon or manageable by conventional means.

CONCLUSION

The encouraging response rates and duration achieved with this combination of Navelbine/doxorubicin under the conditions of this study deserve further randomized comparative trials with standard regimens.

[CA 15-3 and breast cancer]

The precise clinical value of CA 15-3 antigen has yet to be determined. With no role in screening for early breast cancer and, even if CA 15-3 seems to be correlated with bulky initial tumor burden, it appears to have no independent prognostic value. The clinical interest of CA 15-3 remains the early detection of the first recurrence. In this regard, more than 75% of first recurrences (all sites included) are associated with a significant rise in CA 15-3 levels, with a particular sensitivity for bone, liver, and lung metastases but which appears lower for locoregional recurrences. More sensitive and specific than CEA, and this whatever the site of recurrence, the rise of CA 15-3 may precede the clinically or radiologically diagnostic of recurrence by a mean lead time from 6 to 9 months. Furthermore CA 15-3 is a reliable marker for clinical course and seems to be of potential interest in monitoring disease follow-up during therapy. In the situation of a clinically isolated elevation of CA 15-3, which investigations, if any, have to be done?, and if negative must do we initiate a treatment for a "biological recurrence"? All these questions remain still opened, and today on consensual attitude can be recommended. In this issue, only results of well-designed prospective trials could help us to determine more rationally, an optimal diagnostic and therapeutic strategy.

Sequential chemoimmunotherapy with cisplatin, interleukin-2, and interferon alfa-2a for metastatic melanoma

PURPOSE

To evaluate the activity and the toxicity of the combination of cisplatin (CDDP)/recombinant interleukin-2 (rIL-2) and interferon alfa-2a (IFN alpha) in disseminated malignant melanoma (DMM).

PATIENTS AND METHODS

Between December 1990 and March 1992, 39 patients with biopsy-proven metastatic malignant melanoma (MM), bidimensionally measurable lesions and an Eastern Cooperative Oncology Group (ECOG) performance status < or = 2 entered this protocol. Seventy-nine percent had received previous chemotherapy including platinum complex (15%) and alpha interferon (44%). They received CDDP (100 mg/m2 on day 0) followed by IL-2 18.10(6) IU/m2/d continuous intravenous (IV) infusion from day 3 to day 6 and from day 17 to day 21. The cycle was repeated on day 28. Subcutaneous IFN alpha 9.10(6) IU three times weekly was administered throughout the treatment period. From day 66 or 94, patients were administered a maintenance cycle with CDDP 100 mg/m2, subcutaneous IL-2 5.10(6) IU/m2/d from day 15 to day 19 and from day 22 to day 26 and IFN alpha 9.10(6) IU three times weekly repeated every 5 weeks (maximum four cycles).

RESULTS

Among 39 assessable patients, five patients achieved complete responses (CRs). Sixteen patients had partial responses (PRs). The overall objective response rate was 53.8%. The number of metastatic sites was the only response-predictive factor. Toxicity was manageable in a routine patient setting and there was no life-threatening toxicity.

CONCLUSION

These results seem to indicate a possible synergy between CDDP/rIL-2 and IFN alpha in MM.

Chemoimmunotherapy of metastatic malignant melanoma. The Salpétrière Hospital (SOMPS) experience

Optimistic results were obtained in the treatment of 39 patients with surgically incurable metastatic malignant melanoma using a regimen including 2 to 3 monthly induction cycles of cis-diamminedichloroplatinum (CDDP), recombinant interleukin-2 (rIL-2) and interferon alpha-2a (IFN alpha-2a). 33 of 39 patients were pretreated with chemotherapy (dacarbazine and/or fotemustine:31, CDDP:6) and 17 of 39 with IFN alpha-2a. Overall response rate was 54% with 13% achieving a complete response for up to 59+ weeks. Moderate to severe side-effects were reversible on rIL-2 cessation and toxicity was manageable in a routine inpatient setting. These results are especially encouraging as they were seen in previously treated patients, classically low responders, including 3 who were resistant to cisplatin or other platinum complexes. The question remains if this regimen bypasses traditional mechanisms of drug resistance.

Antitumoral activity of bombesin analogues on small cell lung cancer xenografts: relationship with bombesin receptor expression

Gastrin releasing peptide (GRP), the human homologue of bombesin (BN), is an autocrine growth factor for small cell lung cancer (SCLC) cells. The synthetic octapeptides [D-cpa1-beta-Leu8-des-Met9]litorin (BIM 26182) and [D-Phe6-Leu13-CH2NH-Cpa14]bombesin(6-14)NH2 (BIM 26189) are potent GRP/BN antagonists of the proliferation of 3T3 and rat pancreas cells. The effect of these analogues on the proliferation of four SCLC cell lines (SCLC 6, SCLC 41, SCLC 75, SCLC 74R) was tested in vitro and in vivo. Two of these SCLC lines (SCLC 41M and SCLC 75) had receptors for BN/GRP and expressed the prepro-GRP mRNA. BIM 26182 and BIM 26189 inhibited [3H]thymidine incorporation into the DNA of SCLC 41 cells, stimulated [3H]thymidine incorporation in SCLC 6, and had no effect on the two other cell lines. The SCLC implanted s.c. in nude mice were treated with either BIM 26182 or BIM 26189. BIM 26182 and BIM 26189 injected at the doses of 50 micrograms twice a day (s.c.) around the tumor for 10 to 21 days delayed the growth of SCLC 41 and of SCLC 75. The maximal effect was observed during the treatment period, after which the tumors regrew, suggesting a cytostatic effect of these peptides. No inhibitory effect of the peptides on SCLC 74R or SCLC 6 growth was observed. These data suggest that GRP antagonists are able to inhibit the in vitro and in vivo growth of BN/GRP receptors-positive SCLC.

Methionine dependency of malignant tumors: a possible approach for therapy

When methionine (Met), an essential amino acid, was substituted for by its precursor homocysteine (Hcy) in the culture medium, normal cells such as fibroblasts proliferated normally. In contrast, many tumor cells failed to grow or grew at a lower rate. Met dependency is acquired simultaneously with cell transformation, as observed with HBL 100, a human mammary epithelial cell line that acquired increased malignancy as a function of in vitro passage number, and NIH/3T3 (J10), a mouse fibroblast line transformed by transfection with the human HRAS oncogene. A relationship was observed between Met dependency and metastatic potential of the RMS-21, RMS-S4T, and RMS-J1 sublines derived from RMS-0, a rat rhabdomyosarcoma cell line: the higher the metastatic potential of the cell line, the higher the concentration of Met required to maintain its proliferation. Met-independent cells derived from the RMS-0 line, obtained by a progressive decrease of Met in the culture medium lost their tumorigenicity when injected into rats fed with Met-deprived diets. In addition, the in vitro motility of RMS-S4T tumor cells, a marker of metastatic capability, decreased in Met-free Hcy-complemented (Met- Hcy+) medium. Similarly, RMS-0 tumor cells, preincubated in a Met- Hcy+ culture medium for 24 hours, evidenced a decreased capacity to form lung colonies when injected into syngeneic rats: the median number of lung colonies was 27 and 3 (P less than .05) for cells cultivated in Met+ Hcy- and Met- Hcy+ media, respectively. An amino acid-defined mixture reproducing casein composition was used as a protein source in the diets fed to RMS-J1 tumor-bearing rats. Dietary substitution of Hcy for Met (i.e., met deprivation) resulted in decreased tumor growth (from 44.4 +/- 1.0 to 40.6 +/- 1.4; P less than .05) and prevention of metastatic spread (from 37 to 0; P less than .05). In conclusion, exogenous Met can be substituted for Hcy to maintain the survival of normal cells but is essential for tumor cell growth in vivo as well as in vitro. Therefore, this defect of cancerous versus normal cells could be used for a therapeutic purpose.

Binding and internalization of exogenous glycosaminoglycans in weakly and highly metastatic rhabdomyosarcoma cells

The fate of exogenous glycosaminoglycans in cultures of strongly (RMS 0) and weakly (RMS 8) metastatic rat rhabdomyosarcoma cells was studied. The time course and concentration dependence of binding and internalization of the radiolabeled sulfated glycosaminoglycans were determined. Weakly metastatic cells took up heparin, heparan and dermatan sulfates into their pericellular compartment at a higher rate than the strongly metastatic RMS 0 cells. The RMS 8 cells exhibited about two times more binding sites for these iduronic acid containing glycosaminoglycans, and internalized higher amounts of them than the RMS 0 cells. The uptake of the chondroitin sulfate into the peri- and intracellular compartments of both cell types was about 5-15% of that of the other glycosaminoglycans studied. The specificity of displacement of the pericellular heparin and dermatan sulfate by the unlabeled glycosaminoglycans indicates the involvement of specific structural features of the polysaccharide chains in the interactions of glycosaminoglycans with the surface of rhabdomyosarcoma cells, beside ionic forces due to the polyanionic character of the glycosaminoglycans. Heparin and heparan sulfate degradation products, mainly large oligosaccharides, were recovered from the surface of RMS 0 cells but were absent on the surface of the RMS 8 cells. About 30% of the internalized heparin and heparan sulfate was present in the partially degraded form in both cell types. Oligosaccharides derived from glycosaminoglycans were not released into the medium. The decrease in the amount of iduronic acid containing glycosaminoglycans internalized by the highly invasive cells seems to be correlated with an increased cell-associated degradation and with an apparent loss of glycosaminoglycan binding sites on the cell surface.

Promotion of micrometastasis proliferation in a rat rhabdomyosarcoma model by epidermal growth factor

Using a rat rhabdomyosarcoma 9-4/0, we investigated the role of epidermal growth factor (EGF) in tumor dissemination. In vitro, we detected high-affinity EGF receptors on tumor cells and stimulation of their proliferation by EGF. When injected iv, EGF-pretreated cells demonstrated an increased capacity to form lung colonies and to invade lymphatic tissue. In vivo, EGF treatment led to increased metastatic spread of subcutaneous tumors. When primary tumors were ablated, and the treatment was given from the time of graft until ablation (seeding step), no effect on metastatic spread was noticed. When treatment was given from the time of ablation until death (growth step), EGF increased the number of lung metastases and of invaded lymph node sites.

In vivo emergence of a highly metastatic tumour cell line from a rat rhabdomyosarcoma after treatment with an alkylating agent

Rats bearing a transplanted nickel-induced rhabdomyosarcoma (RMS 9-4/0), treated with chlorozotocin (CZT), an alkylating agent, showed an amplified metastatic invasion of the lung (median of 165 lung tumour nodules, compared to 3 for untreated controls). A higher level of metastatic invasion (200 nodules) was reached spontaneously after the grafting of the S4T line, which was obtained by successive in vivo passages of RMS 9-4/0 cells in CZT treated rats. S4T tumour cells also invaded the liver and a considerable proportion of the lymph nodes. The NT4T line, obtained by successive in vivo passages in untreated rats, showed a lesser degree of enhancement of metastatic capacity (57 nodules). Both derived lines proved to be more aggressive than the parental, proliferated more rapidly, and were resistant to CZT toxicity. Only the non-treated lineage became more resistant to NK lysis. The S4T line lost its myogenic differentiation and was best described as a fibrohistiosarcoma, whereas NT4T did not. Chromosome analysis demonstrated a reduced range of chromosome number per cell in both lines. We conclude that both S4T and NT4T tumours became more metastatic than RMS 9-4/0 as the result of tumour progression through in vivo passages, and that in addition S4T acquired a spontaneously higher metastatic potential, similar to that which occurred in rats grafted with RMS 9-4/0 or NT4T tumours and treated by CZT. This suggests an inheritable mutation in the S4T line.

[Hepatic involvement in secondary syphilis]

A case of secondary syphilitic hepatitis is reported. A 49-year old woman was admitted for weight-loss, fever, hepatomegaly and splenomegaly. Diagnosis of syphilitic hepatitis was based on cholestasis associated with positive serologic tests for syphilis without other immunological disturbances. Biopsy of the liver showed a moderate infiltration in and around the portal tracts. Immunofluorescence study for treponema was negative. Rapid improvement was obtained with penicillin initially associated with steroid therapy. Liver involvement in secondary syphilis is characterized by anicteric cholestasis, an inflammatory syndrome, and periportal infiltrate inconstantly associated with centrilobular necrosis, granulomatous reaction and presence of treponemas in the lesions. Due to the increasing frequency of sexually transmitted diseases, this diagnosis could become more frequent.

Amplified pulmonary metastases of a rat rhabdomyosarcoma in response to nitrosourea treatment

Repeated observations in our laboratory show that the chloroethylnitrosourea of cysteamine ( CNCC ) induces slowed tumor growth rate and decreased lymph node metastasis in rats bearing a rhabdomyosarcoma but concomitantly enhances metastatic dissemination in the lung. Tumors obtained by sc graft of tumor cells, in syngeneic rats, gave a reproducible pattern of metastases at nodal and pulmonary sites after a 60-80-day period. CNCC was administered orally at a dose of 50 mg/kg once a week for 5 weeks beginning at the time of tumor appearance. Forty-five of 46 CNCC -treated rats had lung metastases with 95 (+/- 9.7) nodules; in the control group 29 of 41 rats had lung metastases with 7 (+/- 1.5) nodules. This amplifying effect was found after treatment with two other nitrosoureas (chlorozotocin and hydroxyethylchloroethylnitrosourea ) but not with cyclophosphamide and methotrexate. Lung metastatic amplification was also observed after treatment of the 13762 mammary adenocarcinoma in Fischer rats and treatment of nickel-induced soft tissue tumor. Several hypotheses have been proposed. The dissociated effect of nitrosourea on local tumor, lymph nodes, and pulmonary metastases does not support the concept of systemic immunosuppression as the main mechanism of this phenomenon, but a decrease of local immunological defenses exerted by NK cells, for example, could be possible. Alternatively, a direct effect of the drug on lung tissue, especially lesions of endothelial tissue, could be responsible for the observed effect. Nitrosourea treatment of rats after surgical excision of the tumor, as adjuvant chemotherapy, was responsible for an amplification effect in association with local recurrences. From this fact we hypothesized that nitrosourea treatment could modify the equilibrium of cell subpopulations in the tumor by selecting highly metastatic drug-resistant variants. Although the mechanism of the amplifying effect of nitrosoureas has not been elucidated, our study shows a possible risk in the use of these drugs for inductive or adjuvant chemotherapy.