The use of immunosuppressive therapy in MDS: clinical outcomes and their predictors in a large international patient cohort

Most studies of immunosuppressive therapy (IST) in myelodysplastic syndromes (MDS) are limited by small numbers and their single-center nature, and report conflicting data regarding predictors for response to IST. We examined outcomes associated with IST and predictors of benefit in a large international cohort of patients with MDS. Data were collected from 15 centers in the United States and Europe. Responses, including red blood cell (RBC) transfusion independence (TI), were assessed based on the 2006 MDS International Working Group criteria, and overall survival (OS) was estimated by Kaplan-Meier methods. Logistic regression models estimated odds for response and TI, and Cox Proportional Hazard models estimated hazards ratios for OS. We identified 207 patients with MDS receiving IST, excluding steroid monotherapy. The most common IST regimen was anti-thymocyte globulin (ATG) plus prednisone (43%). Overall response rate (ORR) was 48.8%, including 11.2% (95% confidence interval [CI], 6.5%-18.4%) who achieved a complete remission and 30% (95% CI, 22.3%-39.5%) who achieved RBC TI. Median OS was 47.4 months (95% CI, 37-72.3 months) and was longer for patients who achieved a response or TI. Achievement of RBC TI was associated with a hypocellular bone marrow (cellularity < 20%); horse ATG plus cyclosporine was more effective than rabbit ATG or ATG without cyclosporine. Age, transfusion dependence, presence of paroxysmal nocturnal hemoglobinuria or large granular lymphocyte clones, and HLA DR15 positivity did not predict response to IST. IST leads to objective responses in nearly half the selected patients with the highest rate of RBC TI achieved in patients with hypocellular bone marrows.

Cytogenetic clonal evolution in myelodysplastic syndromes is associated with inferior prognosis

BACKGROUND

The karyotype of bone marrow cells at the time of diagnosis is a strong prognostic parameter for overall survival as well as acute myeloid leukemia (AML) progression in patients with myelodysplastic syndromes (MDS). However, to the authors' knowledge, few data exist regarding the prognostic impact of cytogenetic clonal evolution during the course of MDS.

METHODS

The authors evaluated follow-up karyotype analyses in 549 patients from the Dusseldorf MDS Registry.

RESULTS

Clonal evolution was detectable in 24% of the entire cohort and in 18% of 294 patients receiving best supportive care. The authors noted a clear adverse effect of clonal evolution on the risk of leukemic transformation (hazard ratio, 2.233; P = .036) and overall survival (hazard ratio, 3.677; P<.001). The authors also analyzed the prognostic influence of subclones detectable at the time of diagnosis. Again, such a finding was associated with a significantly shorter overall survival and a higher 5-year-probability of acute myeloid leukemia progression (30% vs 22%).

CONCLUSIONS

The results of the current study support the belief that follow-up karyotype analyses should be performed, especially in patients with lower-risk and intermediate-risk MDS, to identify those patients who are at higher risk of disease progression and therefore might benefit from earlier or more intensive treatment. Cancer 2017;123:4608-4616. © 2017 American Cancer Society.

Cellularity, characteristics of hematopoietic parameters and prognosis in myelodysplastic syndromes

BACKGROUND

Myelodysplastic syndromes (MDS) present with a normo- or hyperplastic bone marrow in most cases. We aimed at a characterization of patients with different types of cellularity.

METHODS

We assessed marrow cellularity both by histology and cytology in 1270 patients and analyzed hematologic, cytogenetic, and prognostic parameters accordingly.

RESULTS

The concordance of the assessment of cellularity differed dramatically between histology and cytology as only 36.5% were described as hypocellular by both methods (P < 0.0005) (hypocellular 16.4%, normocellular 23.3%, hypercellular 60.3%). There were no major differences with regard to hematopoietic insufficiency. The presence of fibrosis was associated to hypercellular bone marrow. Median survival differed from 38 months in hypocellular, 42 months in normocellular, and 25 months in hypercellular MDS (P < 0.0005). AML progression rates were 33% for hypercellular MDS after 2 yr, whereas hypo- and normocellular had a progression rate of 19% after 2 yr (P = 0.018). IPSS and IPSS-R were able to identify different risk groups within all three cellularity groups.

CONCLUSION

Based on our data, hypocellular patients obviously do not present as a separate entity, as there were no striking differences with regard to cytogenetics and WHO types. Assessment of cellularity should be performed by histopathology.

Proposed score for survival of patients with myelodysplastic syndromes

BACKGROUND

Patient selection for various therapies in myelodysplastic syndromes (MDS) is based on prognostic factors, scoring systems and the individual life expectancy. However, most established risk scores include mainly disease-related parameters and thus focus on leukaemia-transformation rather than survival.

PATIENTS AND METHODS

To establish a risk score optimized for prediction of survival, we analysed international prognostic scoring system (IPSS)-related and IPSS-independent variables in 400 patients with primary MDS (median age: 71 years; range 18-91) of the Austrian MDS platform. Patients were randomly split into a learning sample (60%) and validation sample (40%). External validation was performed on 93 patients from the Heinrich Heine University (Duesseldorf/Germany).

RESULTS

By multivariate analysis, IPSS, ferritin, age and comorbidities were found to be independent predictive variables concerning survival. Based on weighing these prognostic parameters against each other, we established a novel survival score employing IPSS, ferritin (< 900 ng/mL = 0; ≥ 900 ng/mL = 1), age (< 70 years = 0; 70-79 years = 1; ≥ 80 years = 1.5) and HCT-CI comorbidity (low/intermediate = 0; high = 0.5). Using this score, four prognostic risk groups could be discriminated in the validation sample, with highly significant differences in life expectancy [median survival: LowS (score 0), not reached; Int-1S (score 0.5-1.0), 3.84 years; Int-2S (score 1.5-2.0): 2.72 years; and HighS (score > 2.0): 0.80 years; P < 0.0001].

CONCLUSIONS

Our newly proposed score may be a useful tool for survival prediction in MDS and helpful in patient selection for various therapies in daily practice and clinical trials.

Prognostic molecular markers in myelodysplastic syndromes

Cytogenetic findings in myelodysplastic syndromes play an important role in diagnosis, prognostication and clinical decision making. Therefore, they became an important aspect in scoring systems such as the International Prognostic Scoring System (IPSS) and the WHO-adapted Prognostic Scoring System (WPSS). Ongoing efforts to refine the categorization of karyotypes with regard to prognosis and therapeutic options will change scoring systems in the near future. In order to learn more about the pathophysiology of myelodysplastic syndromes, various molecular genetic aberrations are identified and their impact on prognosis discussed. New screening methods such as gene expression or single nucleotide polymorphism analysis are good candidates to find entrance in clinical practice in the future as they are useful tools in further elucidation of the underlying defects in myelodysplastic syndromes and the development of more specific classifications of the disease concerning risk assessment.

Gene expression profiling for molecular distinction and characterization of laser captured primary lung cancers

Methods

We examined gene expression profiles of tumor cells from 29 untreated patients with lung cancer (10 adenocarcinomas (AC), 10 squamous cell carcinomas (SCC), and 9 small cell lung cancer (SCLC)) in comparison to 5 samples of normal lung tissue (NT). The European and American methodological quality guidelines for microarray experiments were followed, including the stipulated use of laser capture microdissection for separation and purification of the lung cancer tumor cells from surrounding tissue.

Results

Based on differentially expressed genes, different lung cancer samples could be distinguished from each other and from normal lung tissue using hierarchical clustering. Comparing AC, SCC and SCLC with NT, we found 205, 335 and 404 genes, respectively, that were at least 2-fold differentially expressed (estimated false discovery rate: < 2.6%). Different lung cancer subtypes had distinct molecular phenotypes, which also reflected their biological characteristics. Differentially expressed genes in human lung tumors which may be of relevance in the respective lung cancer subtypes were corroborated by quantitative real-time PCR.

Genetic programming (GP) was performed to construct a classifier for distinguishing between AC, SCC, SCLC, and NT. Forty genes, that could be used to correctly classify the tumor or NT samples, have been identified. In addition, all samples from an independent test set of 13 further tumors (AC or SCC) were also correctly classified.

Conclusion

The data from this research identified potential candidate genes which could be used as the basis for the development of diagnostic tools and lung tumor type-specific targeted therapies.

The proteasome inhibitor bortezomib acts differently in combination with p53 gene transfer or cytotoxic chemotherapy on NSCLC cells

In this report, the effects of a combined treatment with the proteasome inhibitor bortezomib and either a recombinant adeno-associated virus type 2 (rAAV-2)-mediated p53 gene transfer or chemotherapeutic agents, docetaxel and pemetrexed, were tested on p53 positive and p53negative non-small cell lung cancer (NSCLC) cell lines. The combination of bortezomib and rAAV-p53 led to a significant synergistic inhibition of cell growth between 62-82% depending on the p53 status of the cell line and drug concentration. Surviving cells of the combined treatment showed a significant reduced ability to form colonies. Enhanced cell toxicity was associated with a 5.3-14.4-fold increase of the apoptotic rate and intracellular p53 level up to 50.4% following vector-mediated p53 restoration and bortezomib treatment. In contrast, an antagonistic effect on tumor cell growth and colony formation was observed for the combination of bortezomib and docetaxel or pemetrexed as a reduction of cell growth between 31 and 48% was found in comparison to 50% using the single agents. Lower cytotoxic effects were associated with significantly reduced apoptosis and an increase of clonogenic growth. The observed antagonistic effects between bortezomib and docetaxel or pemetrexed might influence clinical trials using these compounds. Conversely, p53 restoration and bortezomib treatment led to enhanced, synergistic tumor cell toxicity.

The influence of the pituitary tumor transforming gene-1 (PTTG-1) on survival of patients with small cell lung cancer and non-small cell lung cancer

BACKGROUND

PTTG-1 (pituitary tumor transforming gene) is a novel oncogene that is overexpressed in tumors, such as pituitary adenoma, breast and gastrointestinal cancers as well as in leukemia. In this study, we examined the role of PTTG-1 expression in lung cancer with regard to histological subtype, the correlation of PTTG-1 to clinical parameters and relation on patients' survival.

METHODS

Expression of PTTG-1 was examined immunohistochemically on formalin-fixed, paraffin-embedded tissue sections of 136 patients with small cell lung cancer (SCLC) and 91 patients with non-small cell lung cancer (NSCLC), retrospectively. The intensity of PTTG-1 expression as well as the proportion of PTTG-1 positive cells within a tumor was used for univariate and multivariate analysis.

RESULTS

PTTG-1 expression was observed in 64% of SCLC tumors and in 97.8% of NSCLC tumors. In patients with SCLC, negative or low PTTG-1 expression was associated with a shorter mean survival time compared with patients with strong PTTG-1 expression (265 +/- 18 days vs. 379 +/- 66 days; p = 0.0291). Using the Cox regression model for multivariate analysis, PTTG-1 expression was a significant predictor for survival next to performance status, tumor stage, LDH and hemoglobin. In contrast, in patients with NSCLC an inverse correlation between survival and PTTG-1 expression was seen. Strong PTTG-1 expression was associated with a shorter mean survival of 306 +/- 58 days compared with 463 +/- 55 days for those patients with no or low PTTG-1 intensities (p = 0.0386). Further, PTTG-1 expression was associated with a more aggressive NSCLC phenotype with an advanced pathological stage, extensive lymph node metastases, distant metastases and increased LDH level. Multivariate analysis using Cox regression confirmed the prognostic relevance of PTTG-1 expression next to performance status and tumor stage in patients with NSCLC.

CONCLUSION

Lung cancers belong to the group of tumors expressing PTTG-1. Dependent on the histological subtype of lung cancer, PTTG-1 expression was associated with a better outcome in patients with SCLC and a rather unfavourable outcome for patients with NSCLCs. These results may reflect the varying role of PTTG-1 in the pathophysiology of the different histological subtypes of lung cancer.

Quantitative real-time PCR for titration of infectious recombinant AAV-2 particles

In this report, we present a fast, reliable and easy to perform method to quantify infectious titers of recombinant AAV-2 (rAAV-2) particles using the LightCycler technology, which is independent from the therapeutic transgene and without the presence of a marker gene. The method is based on the life cycle of AAV-2: after infection of the host cell, the single stranded (ss) AAV-2 genome is converted into a double stranded (ds) form. Following infection with rAAV-2, HeLa cells were lysed and ssDNA of transcriptionally inactive particles were efficiently removed by ssDNA-specific S1 nuclease digestion. The remaining viral dsDNA can be quantified by quantitative real-time PCR (qPCR). For validation of the new method, rAAV-2 preparations were analyzed by two other standard methods for titration of infectious particles in parallel, i.e. the infectious center assay (ICA) as well as flow cytometry using GFP as a marker. Comparing the infectious titers of 40 different AAV-2 fractions assessed by qPCR with the titers determined by FACS analysis a significant correlation (r=0.87, p<0.001) with a mean ratio of the titers assessed by qPCR and FACS of 1.92 (S.D.+/-1.59) was found. Further, the titers of seven rAAV-2 fractions using qPCR and ICA covering 5 log ranges were compared and a significant correlation was found between the results (r=0.80, p<0.001) with a mean ratio of 3.38 (S.D.+/-1.79), respectively.