POS0464 DIFFERENTIAL MOLECULAR PROFILES IN THE SYNOVIAL TISSUE AND SYNOVIAL FLUID OF PATIENTS WITH RHEUMATOID ARTHRITIS AND PSORIATIC ARTHRITIS

Background

The differential diagnosis of Rheumatoid Arthritis (RA) and Psoriatic arthritis (PsA) is often difficult due to the similarity of symptoms and the unavailability of reliable clinical biomarkers. Molecular alterations have been suggested to contribute to the pathophysiological processes in the knee joint, and it is known that chronic inflammation induces significant changes in the synovial tissue (ST) and synovial fluid (SF) lipidome and proteome.

Objectives

We aimed to evaluate whether specific characteristics in the molecular profiles from ST and SF could support the differential diagnosis of these diseases.

Methods

ST frozen samples of patients affected by RA (n=6), PsA (n=12) and control donors (n=10) were compared using Matrix-Assisted Laser Desorption Ionization Mass Spectrometry Imaging (MALDI-MSI) for spatially resolved lipid analysis. To this end, tissue sections were measured on a RapifleX MALDI-TOF/TOF instrument. Next, a targeted approach based on multiple reaction monitoring (MRM-MS) was performed to further validate the lipidomic alterations reported by MALDI-MSI between RA and PsA tissues. In this case, lipids extracted from SF (control donors (n=4), RA (n=21) and PsA (n=27)) were analyzed in a QTRAP 4000 mass spectrometer for the targeted analysis of 84 lipid species. Finally, a quantitative proteomic analysis was carried out on FFPE ST from RA (n=13), PsA (n=13) and controls (n=8) by nLC-MS/MS analysis using a TimsTOF Pro system (Bruker). Statistical analyses were performed using GraphPad Prism, Metaboanalyst and Perseus software.

Results

Lipid profiles in ST from PsA and RA were unequivocally distinguished by MALDI-MSI followed by PCA-DA, and were also different comparing with control tissues. Interestingly, several lipid species, including sphingomyelins, phosphatidylcholines (PC) and phosphatidylethanolamines (PE), presented the greatest separation power to classify RA and PsA tissue samples. ANOVA analysis found 35 lipid species significantly different among the study groups, most of them significantly increased in RA and PsA compared to controls. Particularly, 11 lipids showed higher levels in PsA tissues compared with RA, including several PC and PE. The spatial distribution of these PE species was associated with areas of the sublining layer with increased vascularity and inflammatory cell infiltrates, according to MALDI-MSI images. On the other hand, RA and PsA patients were also correctly classified based on the SF levels of all quantified lipid species according to PCA and clustering analysis. Finally, the proteomic analysis quantified around 2,500 distinct proteins in the ST, including several related with lipid metabolism. Near 300 proteins showed altered abundance in the pathological tissues compared to healthy controls (FDR 0.01%, Figure 1A), being the small subset increased in controls mainly extracellular matrix proteins. The comparison between RA and PsA ST led to the identification of a panel of 36 proteins discriminating the two tissues with high statistical significance (p-value <0.01). In this comparison, all proteins except two appeared increased in RA (Figure 1B). A discriminant analysis shows the usefulness of this protein panel to differentiate the two diseases (Figure 1C).

Figure 1.

Results from the proteomic analysis carried out on synovial tissues. A) Heatmap showing the differential protein profiles between synovial tissues (PsA and RA) and healthy controls (CTL), at FDR 0.01. B) Characteristic protein panel discriminating PsA and RA tissues (p-value < 0.01). C) Discriminant analysis performed using this protein panel.

Conclusion

Our study shows distinct molecular profiles between RA and PsA synovial tissue and synovial fluid, and reports potential clinically useful lipid and protein markers for the differential diagnosis of these diseases.

Disclosure of Interests

None declared.

POS0185 IDENTIFICATION AND VALIDATION OF TWO NOVEL SERUM BIOMARKERS ASSOCIATED WITH THE SEROLOGICAL STATUS OF RHEUMATOID ARTHRITIS PATIENTS

Background:

Despite the diagnostic value of Rheumatoid Factor (RF) and Anti-Citrullinated Protein Antibodies (ACPA), more serological markers are needed in order to improve early diagnosis and treatment response of the Rheumatoid Arthritis (RA) patients. Increased knowledge about how these two major autoreactivities arise is crucial for understanding how RA develops and what mechanisms drive pathogenesis.

Objectives:

We aimed to investigate, using a proteomic strategy, novel protein biomarkers associated with RF and/or ACPA that might be useful to stratify seropositive and seronegative RA patients.

Methods:

A shotgun proteomic analysis was performed on 80 sera from the RA cohort of the Rheumatology Unit of the University Hospital of Santiago de Compostela (CHUS). Sera were classified as seropositive or seronegative according to their RF and ACPA values, and were then analyzed employing the iTRAQ labelling technique (Sciex) followed by LC-MALDI-MS/MS analysis (MALDI-TOF). A Multiple Reaction Monitoring (MRM) method was subsequently developed using the Skyline Software for the simultaneous quantification of 26 peptides belonging to ten putative protein biomarkers. The quantitative targeted analysis was performed using peptides with isotope labelled amino acids as internal standards. Serum levels of orosomucoid 1 (ORM1) and haptoglobin (HPT) were measured using commercially available ELISA Kits in the whole RA cohort (n=260) from the Rheumatology Unit of the University Hospital of A Coruña (HUAC).

Results:

For the initial screening, eighty sera were grouped according to the ACPA/RF status in 4 pools (20 patients/pool). Using an iTRAQ technology-based quantitative proteomic approach, the abundance of eleven proteins was altered in the sera from ACPApos/RFpos, 13 proteins in ACPAneg/RFpos and 12 proteins in ACPApos/RFneg, compared to ACPAneg/RFneg. Vitamin D binding protein (VTDB) was the unique protein that resulted increased in all the comparisons. For the biomarker verification phase, all the samples from the CHUS cohort were analyzed individually (n=80). Using the MRM technology, 26 peptides belonging to ten putative protein biomarkers associated with double positivity were simultaneously quantified. The statistical analysis showed a significant modulation of 9 peptides (belonging to 4 different proteins) in ACPApos/RFpos, 7 peptides (5 proteins) in ACPAneg/RFpos, and 9 peptides (6 proteins) in ACPApos/RFneg compared to ACPAneg/RFneg (p<0.05). Two acute phase reactants (ORM1 and HPT) displayed the same modulation in both screening and verification phases, thus confirming their association with the double positivity. Finally, in the biomarker validation phase, a total of 260 patients from CHUAC were included (Table 1). RA patients were classified as follows: (1) 112 patients (43.1%) were ACPApos/RFpos; (2) 73 patients (28.1%) were ACPAneg/RFneg; (3) 51 patients (19.6%) were ACPAneg/RFpos; and (4) 24 patients (9.2%) were ACPApos/RFneg. Serum levels of ORM1 and HPT (Figure 1), measured by commercial immunoassays, confirmed their increased values in double seropositive patients (p=0,0053 ORM1; p=0,0026 HPT). Finally, the increased level of ORM1 resulted associated with RF rather than ACPA status (p=0,0008 ACPAneg/RFpos); whereas HPT was associated with ACPA rather than RF status (p=0,0112 ACPApos/RFneg).

Table 1.

The different phases of RA biomarker development followed in this study.

DISCOVERYPHASEVERIFICATIONPHASEVALIDATIONPHASESource centerCHUSCHUSCHUACN° ofsamplesn= 4n= 80n= 260ACPA+RF+Pool 1ACPA+RF+20ACPA+RF+112ACPA-RF-Pool 2ACPA-RF-20ACPA-RF-73ACPA-RF+Pool 3ACPA-RF+20ACPA-RF+51ACPA+RF-Pool 4ACPA+RF-20ACPA+RF-24N° ofbiomarkersORM1, ORM2, HPT, A2GL, AACT, RBP4, PLMN, IC1, VDBP, APOBORM1, HPT, A2GL, AACTORM1, HPTFigure 1.

Conclusion:

The determination of ORM1 and HPT in sera provides novel information useful for patient stratification, which might improve diagnostic and prognostic approaches and facilitate the development of personalized medicine strategies in RA.

Acknowledgements:

This work is supported by grants from Fondo de Investigación Sanitaria (RD16/0012/0002, PT17/0019/0014) integrated in the National Plan for Scientific Program, Development and Technological Innovation 2013–2016 and funded by the ISCIII-General Subdirection of Assessment and Promotion of Research-European Regional Development Fund (FEDER) “A way of making Europe”.

Disclosure of Interests:

None declared

A Phospholipid Profile at 4 Months Predicts the Onset of Celiac Disease in at-Risk Infants

Celiac disease (CeD) is a multifactorial disease influenced by both genetic and environmental risk factors. CeD genetic components are mainly due to HLA class II genes, which account for approximately 40% of the disease heritability. The environmental factor is linked to gliadin ingestion. Despite genetic and epigenetic studies, the pathological molecular mechanism remains unclarified. The strong genetic component does not explain more than half of the hereditability; we identified several epigenetic features that contribute to the understanding of the missing hereditability. The lipid profile of infants has been proposed as a potential biomarker of CeD metabolism that can be measured before they exhibit developmental disorders and clinical symptoms. We suggest that the state of the host is a main factor for the abnormal immune response to gluten. Long before any exposure to the offending agent or any production of specific antibodies, several molecular mechanisms are differentially expressed in infants who will develop CeD compared to their peers matched for the same genetic profile. The present study explored the serum phospholipid profile of a group of infants at risk for celiac disease, followed up to 8 years to monitor the onset of CeD. We compared 30 patients who developed the disease with 20 age- and sex-matched peers with similar genetic profiles who did not develop the disease within 8 years. Serum phospholipids were analysed at 4 months, before exposure to gluten, and at 12 months of age, when none showed any marker of disease. In the 30 CeD patients, we also analysed the serum at the time of diagnosis (>24 months). The serum phospholipid profile was fairly constant across 4 and 12 months of age and, in CeD, up to 24–36 months. The phospholipid signature was dramatically different in infants who developed CeD when compared to that of control NY-CeD (Not Yet developing Celiac Disease) peers. We identified a specific serum phospholipid signature that predicts the onset of celiac disease in HLA at-risk infants years before the appearance of antibodies specific for CeD in the serum and before any clinical symptoms, even before gluten introduction into the diet at 4 months. Specifically, lysophosphatidylcholine, phosphatidylcholine, alkylacyl-phosphatidylcholine, phosphoethanolamines, phosphatidylserines, phosphatidylglycerol and phosphatidylinositol were found to be differentially represented in CeD versus NY-CeD. A set constituted by a limited number of alkylacyl-phosphatidylcholine and lyso-phosphatidylcholine, together with the duration of breast-feeding, allows the discrimination of infants who develop celiac disease before 8 years of age from those at a similar genetic risk who do not develop the disease. In addition to recent discovery, our paper unveiled a specifc phopholipid profile, able to discriminate infants who eventually develop celiac disease years before antibodies or clinical symptoms ensue.

Two consecutive phase 1–2 studies of cisplatin (P)-based 1st-line chemotherapy (CT) in elderly patients (pts) with advanced non-small cell lung cancer (NSCLC). The MILES-2P studies

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Background: P-based CT needs prospective testing in elderly pts with advanced NSCLC. In two consecutive studies, with equal design, feasible dose of P combined with gemcitabine (PG) or vinorelbine (PV) were identified and toxicity and activity were described. Methods: Advanced (stage IV or IIIb with supraclavear nodes or pleural effusion) NSCLC pts, aged >70 years, PS 0–1, were eligible. P was given on day (d) 1, starting dose-finding at 50 mg/m2 (level 0), with G (fixed dose: 1000 mg/m2 dd 1&8) or V (fixed dose: 25 mg/m2 dd 1&8); at each level <2 unacceptable toxicities in cycle 1–3 (UT) out of 6 evaluable pts were needed to escalate; CT was given every 3 weeks, up to 6 cycles. A two-stage flexible optimal design was applied at the feasible dose. With rate of pts without UT as endpoint, type I and II error =0.10, p0=0.70, p1=0.85, ≥47 pts without UT out of 60 enrolled were required at the final stage. NCI-CTC for toxicity and RECIST for response coding were used. Results: From June 2002 to November 2004, 159 pts were enrolled (38 in dose-finding and 121 in phase 2); 45% of them were aged ≥75. P was feasible at 60 mg/m2 (level +1) with G, and 40 mg/m2 (level -1) with V. With PG (n=60): 50 (83%) pts without UT; response rate (RR): 43%, 95% exact CI: 31–57; median progression-free (PFS) and overall survival (OAS): 25 and 44 wks, respectively. Toxicity (≥5% of pts): g3 anemia (5%), RBC transfusion (8%), g3–4 platelets (10%), g2–3 cardiac (10%), g2 renal (7%). With PV (n=61): 50 (82%) pts without UT, 2 toxic deaths (1 with febrile neutropenia [FN] and 1 with cardiac toxicity); RR 36%, 95% exact CI: 24–49; median PFS and OAS: 21 and 33 wks, respectively. Toxicity (≥5% of pts): g3 anemia (5%), RBC transfusion (8%), FN (5%), g≥2 neurologic (5%). Conclusions: The combination of cisplatin and gemcitabine (with P 60 mg/m2) is safe, active, and deserves comparison vs single-agent chemotherapy in elderly pts with advanced NSCLC.

No significant financial relationships to disclose.

A randomised clinical trial of two docetaxel regimens (weekly vs 3 week) in the second-line treatment of non-small-cell lung cancer. The DISTAL 01 study

Docetaxel (75 mg m(-2) 3-weekly) is standard second-line treatment in advanced non-small-cell lung cancer (NSCLC) with significant toxicity. To verify whether a weekly schedule (33.3 mg m(-2) for 6 weeks) improved quality of life (QoL), a phase III study was performed with 220 advanced NSCLC patients, < or =75 years, ECOG PS < or =2. QoL was assessed by EORTC questionnaires and the Daily Diary Card (DDC). No difference was found in global QoL scores at 3 weeks. Pain, cough and hair loss significantly favoured the weekly schedule, while diarrhoea was worse. DDC analysis showed that loss of appetite and overall condition were significantly worse in the 3-week arm in the first week, while nausea and loss of appetite were more severe in the weekly arm in the third week. Response rate and survival were similar, hazard ratio of death in the weekly arm being 1.04 (95% CI 0.77-1.39). A 3-weekly docetaxel was more toxic for leukopenia, neutropenia, febrile neutropenia and hair loss; any grade 3-4 haematologic toxicity was significantly more frequent in the standard arm (25 vs 6%). The weekly schedule could be preferred for patients candidate to receive docetaxel as second-line treatment for advanced NSCLC, because of some QoL advantages, lower toxicity and no evidence of strikingly different effect on survival.

Supportive care in patients with advanced non-small-cell lung cancer

The present study describes supportive care (SC) in patients with advanced non-small-cell lung cancer (NSCLC), evaluating whether it is affected by concomitant chemotherapy, patient's performance status (PS) and age. Data of patients enrolled in three randomised trials of first-line chemotherapy, conducted between 1996 and 2001, were pooled. The analysis was limited to the first three cycles of treatment. Supportive care data were available for 1185 out of 1312 (90%) enrolled patients. Gastrointestinal drugs (45.7%), corticosteroids (33.4%) and analgesics (23.8%) were the most frequently observed categories. The mean number of drugs per patient was 2.43; 538 patients (45.4%) assumed three or more supportive drugs. Vinorelbine does not produce substantial variations in the SC pattern, while cisplatin-based treatment requires an overall higher number of supportive drugs, with higher use of antiemetics (41 vs 27%) and antianaemics (10 vs 4%). Patients with worse PS are more exposed to corticosteroids (42 vs 30%). Elderly patients require drugs against concomitant diseases significantly more than adults (20 vs 7%) and are less frequently exposed to antiemetics (12 vs 27%). In conclusion, polypharmacotherapy is a relevant issue in patients with advanced NSCLC. Chemotherapy does not remarkably affect the pattern of SC, except for some drugs against side effects. Elderly patients assume more drugs for concomitant diseases and receive less antiemetics than adults.

Phase I-II study of gemcitabine and paclitaxel in pretreated patients with stage IIIB-IV non-small cell lung cancer

Gemcitabine and paclitaxel are among the most active new agents in non-small cell lung cancer (NSCLC) and are worth considering for second-line chemotherapy. In this phase I-II study, we combined gemcitabine and paclitaxel for second-line treatment of advanced NSCLC. Gemcitabine doses were kept fixed at 1000 mg/m2 on day 1 and 8, and paclitaxel doses were escalated from 90 mg/m2 on day 1 of the 21-day cycle. Thirty-seven patients were treated at six different dose levels. Grade 4 neutropenia was dose-limiting toxicity (DLT), since it occurred in two out of six patients treated at paclitaxel 240 mg/m2; the paclitaxel dose level just below (210 mg/m2) was selected for phase Il evaluation. Non-hematologic toxicity was mild. One complete response (CR) (3%) and 13 partial responses (PR) (36%) were observed in 36 evaluable patients for an overall response rate of 39% (95% C.I., 23-57%). Median duration of response was 35 weeks (range, 8-102). All of the observed objective responses occurred in the 19 patients who had previously responded to the first-line therapy. Median survival was 40 weeks (range, 8-108 weeks). The combination of gemcitabine and paclitaxel is a feasible, well-tolerated, and active scheme for second-line treatment of advanced NSCLC; further evaluation, at least in selected patients, such as those previously responding to first-line chemotherapy, is definitely warranted.

New triplet chemotherapy combination with carboplatin, paclitaxel and gemcitabine plus amifostine support in advanced non small cell lung cancer: a phase II study

New triplet chemotherapy combinations are under investigation in advanced non small cell lung cancer (NSCLC). Carboplatin, plus paclitaxel, plus gemcitabine is among the most active and promising regimens. The use of more aggressive chemotherapy in order to improve results can increase toxicity. Amifostine (WR-2721) reduces toxicity of radiotherapy and chemotherapy and protects selectively a number of normal, but not neoplastic, tissue. Based on this background, we performed a phase II study on carboplatin, plus paclitaxel, plus gemcitabine with amifostine support in advanced NSCLC. Patients received chemotherapy at the following dosage: carboplatin AUC 5, i.v., at day 1; paclitaxel 175 mg/m2, i.v. by 3-hour infusion, at day 1; gemcitabine 1000 mg/m2, i.v. by 3-hour infusion, at days 1 and 8; every 3 weeks for a maximum of 6 cycles. Amifostine was administered at the dose of 740 mg/m2, i.v., at day 1 of each cycle. Seventeen patients entered the study. They were prevalently male, median age was 62 years, PS (ECOG) was 0 in 10 cases (58.8%), 1 in 6 (35.3%) and 2 in 1 (5.9%). Histology was epidermoid in 8 cases (47%) and adenocarcinoma in 9 (53%). We observed 8 (47.5%) objective responses with 2 (11.7%) complete responses. Median time to progression and median survival were 24 and 36 weeks, respectively. Treatment was well tolerated. The main toxicity was as follows: grade 3 neutropenia, grade 2 thrombocytopenia and grade 3 anemia in one (5.8%) case; grade 2 peripheral neurologic toxicity in 3 (17.6%) patients; grade 2 cardiac toxicity (atrial fibrillation) in one case; and grade 3 respiratory toxicity (dispnoea) in one patient. These data indicate that this combination has promising activity and tolerability. A randomized trial comparing carboplatin plus paclitaxel, plus gemcitabine versus carboplatin, plus paclitaxel, plus gemcitabine, plus amifostine in advanced NSCLC is warranted.

Phase I-II study of gemcitabine and carboplatin in stage IIIB-IV non-small-cell lung cancer

PURPOSE

Platinum-based chemotherapy currently represents standard treatment for advanced non-small-cell lung cancer. Gemcitabine is one of the most interesting agents currently in use in advanced non-small-cell lung cancer, and high response rates have been reported when it is administered in combination with cisplatin. The aim of the present study was to evaluate the combination of gemcitabine and carboplatin in a phase I-II study.

PATIENTS AND METHODS

Chemotherapy-naive patients with stage IIIB-IV non-small-cell lung cancer received carboplatin at area under the concentration-time curve (AUC) 5 mg/mL/min and gemcitabine at an initial dose of 800 mg/m2, subsequently escalated by 100 mg/m2 per step. Gemcitabine was administered on days 1 and 8 and carboplatin on day 8 of the 28-day cycle. Dose escalation proceeded up to dose-limiting toxicity (DLT), which was defined as grade 4 neutropenia or thrombocytopenia or grade 3 nonhematologic toxicity.

RESULTS

Neutropenia was DLT, inasmuch as it occurred in three of five patients receiving gemcitabine 1,200 mg/m2. Nonhematologic toxicities were mild. Gemcitabine 1,100 mg/m2 plus carboplatin AUC 5 was recommended for phase II studies. An objective response was observed in 13 (50%) of 26 patients, including four complete responses (15%) and nine partial responses (35%). Median duration of response was 13 months (range, 3 to 23 months). Median overall survival was 16 months (range, 3 to 26 months).

CONCLUSION

The combination of gemcitabine and carboplatin is well tolerated and active. Neutropenia was DLT. The observed activity matches that observable in cisplatin-gemcitabine studies, whereas duration of response and survival are even higher. A phase II trial is under way.

Phase I study of vinorelbine and paclitaxel in small-cell lung cancer

BACKGROUND

Vinorelbine and paclitaxel interfere with mitotic spindle function through different mechanisms of action. Both of the drugs show antitumor activity in small-cell lung cancer when used as single agents; furthermore, in vitro and in vivo studies have shown a synergistic activity between the two drugs.

PATIENTS AND METHODS

Patients with small-cell lung cancer no longer amenable to conventional treatment were entered into a phase I study in which vinorelbine was given at a fixed dose of 30 mg/m2 by 15-min intravenous infusion, whereas paclitaxel was given by 3-h infusion starting 1 h after vinorelbine at an initial dose of 90 mg/m2, which was subsequently escalated by 30-mg/m2 steps. Cycles were repeated every 21 days.

RESULTS

Grade 3 neutropenia was observed only in three patients treated at the fifty dose level. Thrombocytopenia never reached grade 3. Neurotoxicity was considered dose-limiting, since grade 3 peripheral neuropathy occurred in three of five patients treated at the fifth dose level (paclitaxel 210 mg/m2). Other side effects were generally mild. The overall response rate in 22 evaluable patients was 32% (95% CI 13-51%); in particular, 1 complete response (4.5%) and 6 partial responses (27.3%) were observed. The maximally tolerated doses recommended for phase II studies are 180 mg/m2 for paclitaxel and 30 mg/m2 for vinorelbine. The observed myelosuppression was less severe than anticipated on the basis of the effects of each drug alone.

CONCLUSIONS

The promising activity of this drug combination warrants a phase II study in untreated patients with extensive-stage small-cell lung cancer.