MDR1-EXPRESSING CD4+ T CELLS WITH TH1.17 FEATURES RESIST TO NEOADJUVANT CHEMOTHERAPY AND ARE ASSOCIATED WITH BREAST CANCER CLINICAL RESPONSE

BACKGROUND

Multidrug resistance-1 (MDR1) transporter limits the intracellular accumulation of chemotherapies (paclitaxel, anthracyclines) used in breast cancer (BC) treatment. In addition to tumor cells, MDR1 is expressed on immune cell subsets in which it confers chemoresistance. Among human T cells, MDR1 is expressed by most CD8+ T cells, and a subset of CD4+ T helper (Th) cells. Here we explored the expression, function and regulation of MDR1 on CD4+ T cells and investigated the role of this population in response to neoadjuvant chemotherapy (NAC) in BC.

METHODS

Phenotypic and functional characteristics of MDR1+ CD4 Th cells were assessed on blood from healthy donors and patients with BC by flow cytometry. These features were extended to CD4+ Th cells from untreated breast tumor by flow cytometry and RNA-sequencing (RNA-seq). We performed in vitro polarization assays to decipher MDR1 regulation on CD4 Th cells. We evaluated in vitro the impact of chemotherapy agents on MDR1+ CD4+ Th cells. We analyzed the impact of NAC treatment on MDR1+ CD4+ Th cells from blood and tumors and their association with treatment efficacy in two independent BC cohorts and in a public RNA-seq data set of BC tumor biopsies before and after NAC. Finally, we performed single cell (sc) RNAseq of blood CD4+ memory T cells from NAC-treated patients and combined them with an scRNAseq public data set.

RESULTS

MDR1+ CD4 Th cells were strongly enriched in Th1.17 polyfunctional cells but also in Th17 cells, both in blood and untreated breast tumor tissues. Mechanistically, Tumor growth factor (TGF)-β1 was required for MDR1 induction during in vitro Th17 or Th1.17 polarization. MDR1 expression conferred a selective advantage to Th1.17 and Th17 cells following paclitaxel treatment in vitro and in vivo in NAC-treated patients. scRNAseq demonstrated MDR1 association with tumor Th1.17 and Th with features of cytotoxic cells. Enrichment in MDR1+ CD4+ Th1.17 and Th17 cells, in blood and tumors positively correlated with pathological response. Absence of early modulation of Th1.17 and Th17 in NAC-resistant patients, argue for its use as a biomarker for chemotherapy regimen adjustment.

CONCLUSION

MDR1 favored the enrichment of Th1.17 and Th17 in blood and tumor after NAC that correlated to clinical response.

Intra-operative High-Intensity Focused Ultrasound in Patients With Colorectal Liver Metastases: A Prospective Ablate-and-Resect Study

OBJECTIVE

High-intensity focused ultrasound (HIFU) is a recent, non-ionizing and non-invasive technology of focal destruction. Independence from the heat-sink effect of blood flow makes HIFU an interesting technique for focal ablation of liver tumors. Current available technology is based on extracorporeal treatment that limits use of HIFU for the treatment of liver tumors, as elementary ablations are small and must be juxtaposed to treat tumors, resulting in long-duration treatment. We developed an HIFU probe with toroidal technology, which increases the volume of ablation, for intra-operative use, and we assessed the feasibility and efficacy of this device in patients with colorectal liver metastasis (CLM) measuring less than 30 mm.

METHODS

This study was an ablate-and-resect, prospective, single-center, phase II study. All ablations were performed in the area of liver scheduled for liver resection to avoid loss of chance of recovery. The primary objective was to ablate CLM with safety margins (>5 mm).

RESULTS

Between May 2014 and July 2020, 15 patients were enrolled and 24 CLM were targeted. The HIFU ablation time was 370 s. In total, 23 of 24 CLM were successfully treated (95.8%). No damage occurred to extrahepatic tissues. HIFU ablations were oblate shaped with an average long axis of 44.3 ± 6.1 mm and an average shortest axis of 35.9 ± 6.7 mm. On pathological examination, the average diameter of the treated metastasis was 12.2 ± 4.8 mm.

CONCLUSION

Intra-operative HIFU can safely and accurately produce large ablations in 6 min with real-time guidance (ClinicalTrials.gov identifier: NCT01489787).

Cicaderma® in radiation-related dermatitis of breast cancer: Results from the multicentric randomised phase III CICA-RT

Background and purpose

To prevent the occurrence of grade ≥ 2 radiodermatitis after post-operative breast irradiation in patients with non metastatic breast cancer.

Methods

This prospective randomised open-label multicenter study allocated patients from 3 French institutions, ≥18 years, requiring postoperative radiotherapy for histologically proven, early-stage (non-metastatic) unilateral breast adenocarcinoma or in situ breast cancer, with R0 or R1 post-operative status, to receive hygiene rules, associated with either Cicaderma® (Arm A), or preventive treatment according to the investigator preference (mainly hyaluronic acid (ialuset®), essential oils, or water spray, or no medication (Arm B). The primary outcome was to compare the efficacy of Cicaderma® versus local standard management in preventing the occurrence of grade ≥ 2 radiodermatitis. Main secondary objectives include Cicaderma® impact on radiotherapy discontinuation and on skin toxicity (pruritus), pain, quality of life, satisfaction.

Results

The CICA-RT study enrolled from June 2020 to April 2021, 258 women with a median age of 61 (22-91) years in 3 institutions. Patients received either Cicaderma® (A: N = 130) or standard practice (B: N = 128). In the 123 patients who initiated radiotherapy in each arm, 95 (77%, 95%CI 68.8%-84.3%) patients did not develop grade ≥ 2 dermatitis. Sensitivity and per-protocol analyses confirmed the absence of differences between arms.

Conclusion

This prospective study did not meet its primary endpoint of superiority of Cicaderma® over routine practice skin care in terms of prevention of acute radioinduced dermatitis of grade 2 or higher. However, Cicaderma® showed a significant decrease in the occurrence of pruritus with less patients reporting at least once grade ≥ 2 pruritus (A: N = 38, 31%; B: N = 58, 47%; p = 0.009).ClinicalTrials.gov identifier NCT04300829.

Afatinib maintenance therapy following post-operative radiochemotherapy in head and neck squamous cell carcinoma: Results from the phase III randomised double-blind placebo-controlled study BIB2992ORL (GORTEC 2010-02)

OBJECTIVE

We investigated the efficacy and safety of afatinib maintenance therapy in patients with head and neck squamous cell carcinoma (HNSCC) with macroscopically complete resection and adjuvant radiochemotherapy (RCT).

METHODS

This French multicentric randomised phase III double-blind placebo-controlled study included adult patients with ECOG-PS≤2, normal haematological, hepatic and renal functions, and non-metastatic, histologically confirmed HNSCC of the oral cavity, oropharynx, larynx or hypopharynx, with macroscopically complete resection and adjuvant RCT (≥2 cycles of cisplatin 100 mg/m2 J1, J22, J43 and 66Gy (2Gy/fraction, 5 fractions/week, conventional or intensity modulated radiotherapy ≥60Gy). Randomised patients were planned to receive either afatinib (afa arm) or placebo (control arm (C)) as maintenance therapy for one year. Primary endpoint was disease free survival (DFS). A 15% improvement in DFS was expected at 2 years with afatinib (from 55 to 70%).

RESULTS

Among the 167 patients with resected HNSCC included in 19 cancer centres and hospitals from Dec 2011, 134 patients were randomised to receive one-year maintenance afatinib or placebo (afa:67; C:67). Benefit/risk ratio was below assumptions and independent advisory committee recommended to stop the study in Feb 2017, the sponsor decided premature study discontinuation, with a 2-year follow-up for the last randomised patient. 2y-DFS was 61% (95% CI 0.48-0.72) in the afatinib group and 64% (95% CI 0.51-0.74) in the placebo group (HR 1.12, 95% CI 0.70-1.80).

CONCLUSION

Maintenance therapy with afatinib compared with placebo following post-operative RCT in patients with HNSCC did not significantly improve 2y-DFS and should not be recommended in this setting outside clinical trials.

CLINICALTRIALS

gov identifier NCT01427478.

A multicentric randomized phase II clinical trial evaluating high-dose thiotepa as adjuvant treatment to standard chemotherapy in patients with resectable relapsed osteosarcoma

BACKGROUND

The role of high-dose chemotherapy in relapsing osteosarcomas has not been established. We evaluated the efficacy and tolerance of high-dose thiotepa (HDTp) after standard chemotherapy (SCT) in patients with relapsed osteosarcoma.

PATIENTS AND METHODS

This randomised open-label phase II study enrolled patients 1-50 years, with local or metastatic relapse of a high-grade osteosarcoma, not progressive after two cycles of SCT, for whom a complete surgery can be achievable following treatment. The trial assigned enrolled patients in a 1:1 ratio to receive two additional courses of SCT + HDTp and autologous transplantation (Arm A), or SCT alone (Arm B). Surgery for complete resection was scheduled as soon as feasible. Primary endpoint was overall survival (OS). Secondary objectives included progression-free survival (PFS) and safety.

RESULTS

From September 2009 to November 2016, 44 patients were randomised (A:22; B:22). In total, 54.5% were males, and the median age was 16 years (9-32years). The two-year OS rate was 66.7% (95% CI 42.5-82.5) (SCT + HDTp, Arm A) versus 50.0% (95% CI 28.2-68.4) for SCT alone (Arm B). Median OS was 27.4 and 24.8 months, respectively (hazard ratio [HR] 0.826, 95% CI 0.393-1.734; p = 0.6123). Median PFS was 15.6 (8.9-24.9) months in Arm A versus 7.2 (4.8-33.3) months in Arm B, p = 0.3845. Among the 22 patients treated with SCT + HDTp, 16 (72.7%) experienced at least one grade ≥3 adverse events versus 18/22 (81.8%) patients treated with SCT. No toxic death occurred.

CONCLUSION

Adjuvant HDTp failed to significantly improve OS and PFS in resectable relapsed osteosarcomas. Despite a trend of prolonged survival and an acceptable toxicity, thiotepa cannot be recommended.

KEY MESSAGE

HDTp and autologous transplantation added to SCT did not improve OS and PFS in patients with resectable relapsed osteosarcomas. Despite a trend of prolonged survival, thiotepa cannot be recommended.

[Medication reconciliation in a department of internal medicine and infectious and tropical diseases: Feedback after one year practice]

Since April 2015, medication reconciliation is performed in our Department. The objective of this study is to assess the impact of this activity on patients' care after one year of practice.

METHODS

All patients who received medication reconciliation between April-October 2015 and June-December 2016 were included in this retrospective study. Undocumented unintentional discrepancies (DNIND) which result from the comparison between the patient's usual treatments and the medication prescribed at admission were collected. Then, a multidisciplinary discussion was initiated to correct them. The gravity of each DNIND was determined a posteriori.

RESULTS

A statistical comparison between the two studies (2015 vs. 2016) showed the following significant results: decrease in DNIND (0.9 vs. 0.43), in percentage of patients with at least one DNIND (43% vs 31% P <5.10^-6), in reconciliation time (43min vs. 23min) and no significant difference in the distribution of DNIND typology. The main therapeutic classes are: metabolism-diabetes-nutrition (21%), cardiology (18%), pneumology (17%) and neurology-psychiatry (15%). Drugs mainly concerned with DNIND are inhaled anti-asthmatics (13% of the medicines with DNIND), vitamins (8% of DNIND) and the levetiracetam antiepileptic drug (5% of DNIND).

CONCLUSION

The implementation of the reconciliation medication allowed a significant reduction of the DNIND that permits to improve the patient healthcare pathway.

Phase I dose-escalation study of pazopanib combined with bevacizumab in patients with metastatic renal cell carcinoma or other advanced tumors

BACKGROUND

Vascular endothelial growth factor (VEGF) directed therapies are being used in a large number of advanced tumors. Metastatic renal cell carcinoma (mRCC) is highly dependent on the VEGF pathway; VEGF receptor (VEGFR) tyrosine kinase inhibitors (TKI) and humanized VEGF monoclonal antibody have been registered for clinical use in advanced renal cell carcinoma. The VEGFR TKI, pazopanib, with a rather manageable toxicity profile, was preferred to sunitinib by mRCC patients. We investigate the combination of pazopanib and bevacizumab to determine the maximum tolerated dose (MTD) in mRCC and other advanced solid tumors.

METHODS

In this bicentric phase I trial with a 3 + 3 + 3 dose-escalation design, patients received oral pazopanib once daily plus intravenous infusion of bevacizumab every 2 weeks from D15, at one of the four dose levels (DL) planned according to the occurrence of dose limiting toxicities (DLT). 400 and 600 mg pazopanib were respectively combined with 7.5 mg/kg bevacizumab in DL1 and DL2, and 600 and 800 mg pazopanib with 10 mg/kg bevacizumab in DL3 and DL4. Tumor response was evaluated every 8 weeks. Blood samples were assayed to investigate pazopanib pharmacokinetics.

RESULTS

Twenty five patients including seven mRCC were enrolled. Nine patients received the DL1, ten received the DL2. No DLT were observed at DL1, five DLT at DL2, and 3 DLT in the six additional patients who received the DL1. A grade 3 microangiopathic hemolytic anemia syndrome was observed in four (16%) patients. Five (22%) patients achieved a partial response. The mean (range) plasmatic concentrations of 400 and 600 pazopanib were respectively 283 (139-427) and 494 (227-761) μg.h/mL at Day 1, and 738 (487-989) and 1071 (678-1464) μg.h/mL at Day 15 i.e. higher than those previously reported with pazopanib, and were not directly influenced by bevacizumab infusion.

CONCLUSIONS

The combination of pazopanib and bevacizumab induces angiogenic toxicity in patients without any pre-existing renal or vascular damage. Even if a marginal efficacy was reported with five (22%) patients in partial response in different tumor types, the toxicity profile compromises the development of this combination.

TRIAL REGISTRATION

The study was retrospectively registered on ClinicalTrials.gov (number NCT01202032 ) on 2010, Sept 14th.

Abstract B56: An immuno-gene therapy clinical trial evaluating in situ vaccination of malignant pleural mesothelioma with intrapleural delivery of adenovirus-interferon-alpha-2b in combination with chemotherapy

Background: “In situ vaccination” immune-gene therapy has the ability to induce broad, polyclonal anti-tumor responses directed by the patient's own immune system using standard “off the shelf” agents. In this trial, we activated endogenous tumor immunity by injection of an adenovirus expressing a Type I interferon into the pleural space of patients with malignant pleural mesothelioma (MM). Based on preclinical data showing synergy with chemotherapy, all patients then received standard systemic cytotoxic therapy.

Methods: Two doses of intrapleural administration of a replication-defective recombinant adenoviral vector containing the human interferon-alpha (hIFN-α2b) gene at a dose of 3x1011 viral particles were given concomitant with a 14-day course of high-dose cyclo-oxygenase-2 (COX-2) inhibitor (Celecoxib) to reduce side effects and to modify the tumor microenvironment by decreasing PGE- 2 levels. This was followed by standard first-line or second-line chemotherapy agents. Primary outcome measures were safety, overall best response rate, and survival. Bio-correlates were measured.

Results: Forty patients were treated in this study: 18 patients received first-line Pemetrexed-based chemotherapy; 7 patients who had previously received front-line Pemetrexed-based chemotherapy &gt;6 months prior to enrollment received Pemetrexed-based second-line chemotherapy. Additionally, in the second-line chemotherapy arm, fifteen patients (n=15) received gemcitabine-based chemotherapy. Treatment was well tolerated and adverse events were comparable to historical controls. Follow-up chest CT scans demonstrated an overall response rate of 20% by Modified RECIST criteria and disease control rate (DCR) of 85% (partial and complete responses plus stable disease) at initial follow-up scan after the first two cycles of chemotherapy. Encouragingly, median survival for all patients with epithelial histology (including both first and second line) was 26 months (95% CI: 15-ND); median overall survival (MOS) for patients with non-epithelial histology (both first and second line) was 6.5 months (95% CI: 5.50 – ND). [See figure] Historical MOS with first line chemotherapy alone is 13.3 months. No clear predictors for response were identified including: baseline immunologic parameters (i.e. activated T cells or number of regulatory T cells); the presence of the immune-gene signature in their biopsies; peak levels of interferon in blood or pleural fluid; or induction of anti-tumor antibodies, activated T cells, or natural killer cells in peripheral blood.

Conclusions: The combination of intrapleural Ad.IFN-α2b vector, Celecoxib, and systemic chemotherapy proved safe in patients with unresectable malignant pleural mesothelioma. Overall survival rates were significantly higher than historical controls, particularly in the second-line groups. The results of this study support proceeding with a multi-center randomized clinical trial of chemo-immunogene therapy versus standard chemotherapy alone.

Citation Format: D. H. Sterman, E. Alley, J. Friedberg, S. Metzger, J. Stevenson, E. Moon, A. R. Haas, A. Vachani, S. I. Katz, G. Cheng, J. Sun, D. F. Heitjan, L. Litzky, K. Cengel, C. B. Simone, II, M. Culligan, M. Culligan, S. M. Albelda. An immuno-gene therapy clinical trial evaluating in situ vaccination of malignant pleural mesothelioma with intrapleural delivery of adenovirus-interferon-alpha-2b in combination with chemotherapy. [abstract]. In: Proceedings of the AACR Special Conference: Tumor Immunology and Immunotherapy: A New Chapter; December 1-4, 2014; Orlando, FL. Philadelphia (PA): AACR; Cancer Immunol Res 2015;3(10 Suppl):Abstract nr B56.

Quantitative measurement of genome-wide DNA methylation by a reliable and cost-efficient enzyme-linked immunosorbent assay technique

DNA methylation, the conversion of cytosine to 5-methylcytosine, is an important epigenetic modification involved in gene regulation. DNA methylation is essential for normal development whereas abnormal methylation has been implicated in pathological conditions including cancer. To evaluate the extent and variation of genome-wide DNA methylation and its changes during cellular differentiation and tumorgenesis as well as the interplay with histone modifications, accurate and reproducible quantification of the genomic DNA methylation level is required. These measurements have so far been achieved only by sophisticated and costly techniques. Here we report the generation of an enzyme-linked immunosorbent assay (methDNA-ELISA) for the accurate quantification of global DNA methylation levels. The linear region of this methDNA-ELISA ranges from 1 to 10%, making it highly suitable for the typical ranges from 2 to 6% in mammalian genomes. This method requires 10 ng of isolated DNA per sample, thus permitting investigation with minimal amounts of DNA previously not applicable for global DNA methylation analysis, e.g., clinical biopsies or cells collected by microdissection.

Effect of age and body weight on carcass traits and meat composition of rabbits

Abstract. A total of 238 Pannon White growing rabbits were slaughtered at 74, 84 and 94 days of age, at an average body weight of 2.53, 2.84 and 3.15 kg, respectively. Within each age group five body weight categories were formed in such a way that the weight difference between two neighbouring groups was equally 0.3 kg. The design of the experiment permitted the separate examination of the effects exerted by age and body weight on carcass traits and on meat chemical composition of the left hind leg (HL) and that of m. Longissimus dorsi (MLD). Dressing out percentage significantly increased with the increase of age in all body weight categories, as well as with the increase of body weight. The effect of age on the ratio of the fore part of the carcass depended on the body weight: significant difference was found in lower body weight categories. The ratio of the intermediate part of the carcass was not affected by age but it increased in rabbits of higher body weight. The ratio of the hind part of the carcass increased in older animals, while it decreased in rabbits of higher body weight, and this decrease was higher in older rabbits. The ratio of the perirenal fat to reference carcass significantly decreased with age in all body weight categories, but it significantly increased in rabbits of higher body weight. With the advancement of age the moisture content of the HL increased, while that of the MLD did not change. With the increase of body weight, moisture content decreased in both the HL and in the MLD. The fat content of both HL and MLD decreased in older animals, while it increased in rabbits of higher body weight.

Comparison of carcass traits and meat quality of Hyplus hybrid, purebred Pannon White rabbits and their crossbreds

Abstract. The aim of the experiment was to compare the weight gain, carcass traits and meat quality of Hyplus hybrid (HH, offspring of Hyplus PS59 bucks and Hyplus PS19 does, n = 77), purebred Pannon White rabbits (PP, offspring of Pannon White bucks and Pannon White does, n = 84) and their crossbreds (PH: offspring of Pannon White bucks and Hyplus PS19 does, n = 97; HP: offspring of Hyplus PS59 bucks and Pannon White does, n = 79). Pannon White rabbits are selected for body weight gain and for carcass traits by computerised tomography (CT), while Hyplus PS19 females and Hyplus PS59 males are selected on prolificacy and body weight gain, respectively. Rabbits of HP genotype had the highest while those of PP genotype the lowest body weight gain (38.9 and 36.6 g/day, respectively; P<0.05). Pannon White breed had an advantageous influence on dressing out percentage (PP: 58.0%; PH: 58.7%; HP: 57.7%; HH: 57.6%; P<0.001) and on the weight of the m. Longissimus dorsi (PP: 152 g; PH: 143 g; HP: 137 g; HH: 136 g; P<0.001). The fat content of the carcass was lower in the offspring of the Hyplus PS59 bucks (1.15, 1.16, 0.89 and 0.85% for PP, PH, HP and HH rabbits, respectively; P<0.001). Significant differences were found between the meat samples of progenies of purebred Pannon White and the hybrid terminal cross rabbits in the moisture and fat content of hindleg meat (moisture content: PP: 75.5%, HH: 76.1%, P<0.05; fat content: PP: 2.38%, HH: 1.46%; P<0.001). From the view point of dressing out percentage and the volume of the m. Longissimus dorsi the usage of Pannon White genotype is advantageous. Dressing out percentage of the offspring of the early-matured Hyplus PS19 does and Pannon White bucks selected with the help of computerised tomography is remarkable.

Quinidine and procainamide inhibit murine macrophage uptake of apoptotic and necrotic cells: A novel contributing mechanism of drug-induced-lupus

A number of mechanisms have been proposed to explain the etiology of drug-induced lupus (DIL) but the effect of apoptotic and necrotic cell handling has not been previously examined.

OBJECTIVE

To evaluate the effect of quinidine and procainamide at therapeutic range concentrations, on the uptake of apoptotic and necrotic thymocytes by murine peritoneal macrophages and on macrophage survival, as a novel mechanism for DIL.

METHODS

Thymocytes were stained and induced to undergo apoptosis by serum withdrawal. Apoptosis was evaluated using annexin V and propidum iodide (PI) and PI staining. Necrosis was induced by heating. Peritoneal macrophages were treated with quinidine or procainamide at a range of therapeutic concentrations and incubated with stained apoptotic and necrotic thymocytes. Apoptotic and necrotic cell uptake was evaluated by flow cytometry using double staining of thymocytes and macrophages and by confocal microscopy. Green fluorescent latex beads were used as controls for phagocytosis.

RESULTS

Significantly decreased uptake of apoptotic and necrotic cells was seen in the presence of quinidine and procainamide. The documented effect was mainly on the number of apoptotic/necrotic cells per macrophage. Uptake of fluorescent latex beads offered to resident macrophages was not significantly affected by quinidine or procainamide. No pro-apoptotic effect of quinidine or procainamide on macrophages was seen.

CONCLUSION

Quinidine and procainamide at therapeutic range concentrations specifically inhibit clearance of apoptotic and necrotic cells by peritoneal macrophages. Altered handling of apoptotic and necrotic cells may represent a contributing mechanism for DIL.

Static properties of end-tethered polymers in good solution: A comparison between different models

We present a comparison between results, obtained from different simulation models, for the static properties of end-tethered polymer layers in good solvent. Our analysis includes data from two previous studies--the bond fluctuation model of Wittmer et al. [J. Chem. Phys. 101, 4379 (1994)] and the off-lattice bead-spring model of Grest and Murat [Macromolecules 26, 3108 (1993)]. Additionally, we explore the properties of a similar off-lattice model simulated close to the Theta temperature. We show that the data for the bond fluctuation and the Grest-Murat model can be analyzed in terms of scaling theory because chains are swollen inside the Pincus blob. In the vicinity of the Theta point the structure of the chains is essentially Gaussian in the Pincus blob. Therefore, the data for the second off-lattice model can be compared quantitatively to the self-consistent field theory. Different ways to determine the parameters of the self-consistent field theory are discussed.

Successful palliation of stenosing anorectal melanoma by intratumoral injections with natural interferon-beta

Anorectal malignant melanoma is an uncommon tumour. Unlike for cutaneous melanoma, there are few guidelines for its optimal management. In particular, very few palliative treatment strategies have been described for patients with advanced disease. We report on an 80 year old patient with locally advanced anorectal melanoma nearly completely blocking the anal orifice and disseminated metastases. Complete regression of the primary tumour and partial remission of the metastases was achieved with intratumoral injections of natural interferon-beta and systemic administration of dacarbazine. The quality of life in this patient was improved markedly by providing relief from severe rectal pain and bleeding. We propose that conservative treatment strategies such as intratumoral injections with interferon-beta should be considered as a palliative treatment option for stenosing anorectal melanoma before an abdominoperineal resection is recommended.

Association of the MIC-A gene and HLA-B51 with Behçet's disease in Arabs and non-Ashkenazi Jews in Israel

BACKGROUND

Behçet's disease is known to be strongly associated with HLA-B51 in many different ethnic groups. Recently, it was suggested that MIC-A (major histocompatibility complex class I related gene A) is the pathogenic gene after strong association was found between the MIC-A A6 allele of the transmembrane region and the disease in Japanese and Greek patients, although in Greek patients this association was found to be due to linkage disequilibrium with HLA-B51.

OBJECTIVES

To investigate microsatellite polymorphism in Arab and non-Ashkenazi Jewish (NAJ) patients in Israel, to determine whether this association occurs in these groups with Behçet's disease, and elucidate the associated HLA allele of the disease.

METHODS

Forty four Israeli patients with Behçet's disease, including 20 Arabs and 24 NAJ, and 130 ethnically matched healthy controls were examined for MIC-A microsatellite polymorphism of the transmembrane region using polymerase chain reaction, autoradiography, and sequence analysis.

RESULTS

The MIC-A A6 allele was significantly more frequent in the Arab patient group (19/20 (95%)) than in healthy Arab controls (25/42 (60%)) (p(corr)=0.015, OR=12.92), but not in the NAJ patients (16/24 (67%)) compared with NAJ healthy controls (48 /88 (55%)) (p(corr)=1.02, OR=1.667). In stratification analysis of the Arab subgroup, on the confounding effect of MIC-A A6 on HLA-B51 association and vice versa, Behçet's disease was distinctly associated only with HLA-B51.

CONCLUSIONS

These results imply strong association between the MIC-A A6 allele and the disease in Israeli Arabs, but not in Israeli NAJ patients. The stratification analysis indicates that this association results secondarily from a strong linkage disequilibrium with HLA-B51, and the real disease susceptibility gene which plays a part in the development of Behçet's disease is most probably the HLA-B51 allele itself.

Reduced body fat and increased hepatic lipid synthesis in mice bearing interleukin-6-secreting tumor

Chronic secretion of interleukin-6 (IL-6) in mice causes metabolic alteration in the liver, leading to increased synthesis of hepatic cholesterol and fatty acids (FA). Mice were injected with allogeneic tumor cells transduced with the murine IL-6 gene. During the 3 wk after tumor inoculation, elevated serum IL-6 levels were associated with increased spleen and liver weight. Histological examination of sections from the liver showed increased hepatocyte proliferation, resulting in liver enlargement. Body composition analysis revealed that IL-6 caused a significant loss in fat tissue without affecting lean body mass and water content. Hepatic de novo synthesis of FA and cholesterol, as measured by (3)H(2)O incorporation, was three to five times as high in mice secreting IL-6 (IL-6 mice) as in pair-fed mice bearing nonsecreting tumors. This increase in FA and cholesterol synthesis is sufficient to maintain hepatic triglyceride secretion at levels comparable with those of pair-fed mice bearing nonsecreting tumors and, presumably, is the main source of cholesterol and FA-phospholipids necessary for hepatocyte proliferation.

Neutral loss analysis in MALDI-MS using an ion-gate scanning mode

Matrix-assisted laser desorption/ionization reflector time-of-flight (MALDI-reTOF) and electrospray ionization (ESI) mass spectrometry (MS) have become essential tools for the characterization of peptides and proteins. Whereas ESI in combination with a triple quadrupole analyzer allows product ion, precursor ion, and neutral loss analyses, MALDI-reTOF instruments can only be used to record product ion spectra based on the in-source or postsource decay (PSD). We describe a new method to perform neutral loss analyses in MALDI-reTOF instruments in a manner that identifies posttranslationally modified peptides and furthermore retrieves sequence information from peptides. The method is based on the selection of ions in a small time interval to record only signals within the corresponding mass interval. By stepping the time interval through the complete mass range, we obtained a spectrum of stable ions by combining the signals of all individually recorded time intervals. This method furthermore permits PSD fragment ions to be identified, since they reach the detector earlier than the stable ions transmitted in the chosen time interval. The neutral loss analysis were calculated by correlating the PSD fragment ions to the corresponding parent ion detected in this time interval. Moreover, this MALDI-MS mode increased the number of detectable signals in complex peptide mixtures and the signal-to-noise ratio.

Molecular properties and involvement of heparanase in cancer progression and normal development

Heparan sulfate proteoglycans (HSPGs) play a key role in the self-assembly, insolubility and barrier properties of basement membranes and extracellular matrices. Hence, cleavage of heparan sulfate (HS) affects the integrity and functional state of tissues and thereby fundamental normal and pathological phenomena involving cell migration and response to changes in the extracellular microenvironment. Here, we describe the molecular properties, expression and function of a human heparanase, degrading HS at specific intrachain sites. The enzyme is synthesized as a latent approximately 65 kDa protein that is processed at the N-terminus into a highly active approximately 50 kDa form. The heparanase mRNA and protein are preferentially expressed in metastatic cell lines and human tumor tissues. Overexpression of the heparanase cDNA in low-metastatic tumor cells conferred a high metastatic potential in experimental animals, resulting in an increased rate of mortality. The heparanase enzyme also releases ECM-resident angiogenic factors in vitro and its overexpression induces an angiogenic response in vivo. Heparanase may thus facilitate both tumor cell invasion and neovascularization, both critical steps in cancer progression. The enzyme is also involved in cell migration associated with inflammation and autoimmunity. The unexpected identification of a single predominant functional heparanase suggests that the enzyme is a promising target for drug development. In fact, treatment with heparanase inhibitors markedly reduces tumor growth, metastasis and autoimmune disorders in animal models. Studies are underway to elucidate the involvement of heparanase in normal processes such as implantation, embryonic development, morphogenesis, tissue repair, inflammation and HSPG turnover. Heparanase is the first functional mammalian HS-degrading enzyme that has been cloned, expressed and characterized. This may lead to identification and cloning of other glycosaminoglycan degrading enzymes, toward a better understanding of their involvement and significance in normal and pathological processes.

Molecular properties and involvement of heparanase in cancer progression and mammary gland morphogenesis

Tumor spread involves degradation of various components of the extracellular matrix and blood vessel wall. Among these is heparan sulfate proteoglycan, which plays a key role in the self-assembly, insolubility and barrier properties of basement membranes and extracellular matrices. Expression of an endoglycosidase (heparanase) which degrades heparan sulfate correlates with the metastatic potential of tumor cells, and treatment with heparanase inhibitors markedly reduces the incidence of metastasis in experimental animals. Heparin-binding angiogenic proteins are stored as a complex with heparan sulfate in the microenvironment of tumors. These proteins are released and can induce new capillary growth when heparan sulfate is degraded by heparanase. Here, we describe the molecular properties, expression and involvement in tumor progression of a human heparanase. The enzyme is synthesized as a latent approximately 65 kDa protein that is processed at the N-terminus into a highly active approximately 50 kDa form. The heparanase mRNA and protein are preferentially expressed in metastatic human cell lines and in tumor biopsy specimens, including breast carcinoma. Overexpression of the heparanase cDNA in low-metastatic tumor cells conferred a high metastatic potential in experimental animals, resulting in an increased rate of mortality. The heparanase enzyme also released ECM-resident bFGF in vitro, and its overexpression elicited an angiogenic response in vivo. Heparanase may thus facilitate both tumor cell invasion and neovascularization, two critical steps in tumor progression. Mammary glands of transgenic mice overexpressing the heparanase enzyme exhibit precocious branching of ducts and alveolar development, suggesting that the enzyme promotes normal morphogenesis and possibly pre-malignant changes in the mammary gland.

Aleukemic leukemia cutis presenting as benign-appearing exanthema

Aleukemic leukemia cutis is a rare condition characterized by the infiltration of the skin by leukemic cells before their appearance in the peripheral blood or bone marrow. We report here a 62-year-old seemingly healthy patient who presented with disseminated erythematous maculae. A skin biopsy showed leukemia cutis of monocytic type. No involvement of bone marrow or peripheral blood was found. The patient developed acute monocytic leukemia 7 months later. We present this case to illustrate how leukemia cutis can masquerade as a clinically benign-appearing cutaneous eruption without leukemic changes in blood or bone marrow. To confirm the diagnosis of aleukemic leukemia cutis, immunohistochemistry of the skin lesions as well as a complete staging procedure is necessary.

Implementation of force differentiation in the immunoassay

A technique has been developed to apply force to the antibody-antigen complex in a solid-phase immunoassay. Force was applied to the immunochemical complex by labeling the secondary antibody with a magnetically susceptible, micrometer-size particle and placing the assay chamber in a magnetic field of defined magnitude and orientation. The force was strong enough to displace weakly bound particles but was not strong enough to rupture the immunochemical complex. The number of particles bound to the surface after applying the differentiation force was related to the analyte concentration, thus an optical detection scheme was developed for counting the number of particles on the surface. The sensitivity of the force differentiation assay was demonstrated to be one to two orders of magnitude higher than conventional solid-phase immunoassay techniques for model protein, virus, and bacterial analytes, with 99% specificity. The enhanced sensitivity of this assay appears to result from lowering the assay background through the identification of weakly adhesive, nonspecific interactions.

Anti-apoptotic effect of L-arginine in cultured rat mesangial cells

Nitric oxide has been shown to be an important factor in the regulation of apoptosis in mesangial cells. The following studies were conducted to determine whether L-arginine, the metabolic precursor of nitric oxide synthesis, directly modulates programmed cell death in response to a variety of stimuli. Cultured rat mesangial cells were exposed for 24-48 h to one of the following four experimental conditions known to induce apoptosis: i) a cytokine combination consisting of interferon-gamma (50 U/ml), interleukin-1 (5 ng/ml), and LPS (10 microg/ml); ii) 0.75 mM hydrogen peroxide; iii) etoposide, 150 microg/ml; and iv) cis-platinum, 100 microg/ml. Addition of L-arginine resulted in a dose-dependent decrease in apoptosis in cytokine-treated RMC. This effect was demonstrable by gel electrophoresis, diphenylamine assay of DNA fragmentation, and an ELISA to detect DNA oligonucleosomes. The effect was not related to increased osmolality of the test media and was not reproduced by the addition of equimolar D-arginine. L-Arginine also reduced apoptosis and necrosis in RMC that were incubated with etoposide and cis-platinum. In contrast, the amino acid had no beneficial effect on RMC survival following exposure to hydrogen peroxide. These findings indicate that several components of the nitric oxide biosynthetic pathway including the precursor and the enzymatic product independently exert direct effects on apoptosis in cultured rat mesangial cells.

Studies on the dephosphorylation of phosphotyrosine-containing peptides during post-source decay in matrix-assisted laser desorption/ionization

Phosphorylation of tyrosine residues in proteins is a common regulatory mechanism, although it accounts for less than 1% of the total O-phosphate content in proteins. Whereas aromatic phosphorylation sites can be identified by a number of different analytical techniques, sequence analysis of phosphotyrosine-containing proteins at the low picomole or even femtomole level is still a challenging task. This paper describes the post-source decay in matrix-assisted laser desorption/ionization mass spectrometry of phosphotyrosine-containing model peptides by comparing their fragmentation behavior with sequence-homologous unphosphorylated peptides. Whereas the parent ions showed significant losses of HPO3, all phosphorylated fragment ions of the b- and y-series displayed only minor dephosphorylated signals, which often were not detectable. Surprisingly, one of the studied phosphotyrosine-containing sequences displayed, in addition to the [M + H - 80]+ ion, a more abundant [M + H - 98]+ ion, which could be explained by elimination of phosphoric acid. This dephosphorylation pattern was very similar to the patterns obtained for phosphoserine- and phosphothreonine-containing peptides. Because the dephosphorylation pattern of the parent ion is often used to identify modified amino acids in peptides, we investigated possible dephosphorylation mechanisms in detail. Therefore, we substituted single trifunctional amino acid residues and incorporated deuterated phosphotyrosine residues. After excluding direct elimination of phosphoric acid from tyrosine, we could show that the obtained loss of H3PO4 depends on aspartic acid and arginine residues. Most likely the HPO3 group is transferred to aspartic acid followed by cleavage of phosphoric acid forming a succinimide. On the other hand, arginine appears to induce the H3PO4 loss by protonation of phosphotyrosine leaving a phenyl cation.

Farewell my fantasy

In this essay, I seek to place Chen Kaige's Farewell My Concubine not solely within the Chinese matrix of its production but within the transnational matrix of its distribution and viewing; indeed, the film may well have been intended for international audiences, to which the film's numerous awards testify. Yet China, too, has been fascinated with Western ideas, with Freud one particular example. So here I use a Freudian interpretation of the film's rationalization of homosexuality in terms of beating and childhood sexuality, a rationalization that diverges from the Lilian Lee novel on which the film is based.