Thomas Schmitt

Dr. Thomas Schmitt


Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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17 December 2013 in Genome Biology
Verified
Journal Article
Open access
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MRMarcus Renner
Marcus Renner
TWThomas Wolf
Thomas Wolf
HMHannah Meyer
Hannah Meyer
WHWolfgang Hartmann
Wolfgang Hartmann
RPRoland Penzel
Roland Penzel
GMGunhild Mechtersheimer
Gunhild Mechtersheimer
Background: High-grade soft tissue sarcomas are a heterogeneous, complex group of aggressive malignant tumors showing mesenchymal differentiation. Recently, soft tissue sarcomas have increasingly been classified on the basis of underlying genetic alterations; however, the role of aberrant DNA methylation in these tumors is not well understood and, consequently, the usefulness of methylation-based classification is unclear. Results: We used the Infinium HumanMethylation27 platform to profile DNA methylation in 80 primary, untreated high-grade soft tissue sarcomas, representing eight relevant subtypes, two non-neoplastic fat samples and 14 representative sarcoma cell lines. The primary samples were partitioned into seven stable clusters. A classification algorithm identified 216 CpG sites, mapping to 246 genes, showing different degrees of DNA methylation between these seven groups. The differences between the clusters were best represented by a set of eight CpG sites located in the genes SPEG, NNAT, FBLN2, PYROXD2, ZNF217, COL14A1, DMRT2 and CDKN2A. By integrating DNA methylation and mRNA expression data, we identified 27 genes showing negative and three genes showing positive correlation. Compared with non-neoplastic fat, NNAT showed DNA hypomethylation and inverse gene expression in myxoid liposarcomas, and DNA hypermethylation and inverse gene expression in dedifferentiated and pleomorphic liposarcomas. Recovery of NNAT in a hypermethylated myxoid liposarcoma cell line decreased cell migration and viability. Conclusions: Our analysis represents the first comprehensive integration of DNA methylation and transcriptional data in primary high-grade soft tissue sarcomas. We propose novel biomarkers and genes relevant for pathogenesis, including NNAT as a potential tumor suppressor in myxoid liposarcomas.

11 April 2014 in Journal of Experimental & Clinical Cancer Research
Verified
Journal Article
Open access
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CKChristian Koelsche
Christian Koelsche
MRMarcus Renner
Marcus Renner
WHWolfgang Hartmann
Wolfgang Hartmann
RBRegine Brandt
Regine Brandt
BLBurkhard Lehner
Burkhard Lehner
GMGunhild Mechtersheimer
Gunhild Mechtersheimer
Recently, recurrent point mutations in the telomerase reverse transcriptase (TERT) promoter region have been found in many human cancers, leading to a new transcription factor binding site, increased induction of TERT and subsequently to telomere maintenance. We determined the prevalence of TERT promoter mutations in soft tissue sarcomas of 341 patients comprising 16 entities and in 16 sarcoma cell lines covering 7 different soft tissue sarcoma types. The sarcoma tissue samples were collected from the archives of the Institute of Pathology, University of Heidelberg and were composed of 39 myxoid liposarcomas (MLS), 61 dedifferentiated liposarcomas, 15 pleomorphic liposarcomas, 27 leiomyosarcomas, 25 synovial sarcomas (SS), 35 malignant peripheral nerve sheath tumors (MPNST), 40 undifferentiated pleomorphic sarcomas, 17 myxofibrosarcomas, 9 low grade fibromyxoid sarcomas, 10 cases of dermatofibrosarcoma protuberans, 31 solitary fibrous tumors (SFT), 8 extraskeletal myxoid chondrosarcomas, 9 angiosarcomas, 6 alveolar soft part sarcomas, 5 clear cell sarcomas and 4 epithelioid sarcomas. Sarcoma cell lines were obtained from the raising laboratories. A 193 bp fragment of the TERT promoter region covering the hot-spot mutations C228T and C250T was amplified, and direct sequencing of the PCR products was performed. TERT promoter mutations were detected in 36/341 sarcomas. They were highly recurrent in MLS (29/39; 74%) and were in the present MLS series not associated with the phenotype (myxoid vs. round cell variant), tumor grade, tumor site and patients’ median age or gender. In the remaining cases, TERT promoter mutations were found only in 7/302 sarcoma samples and confined to SFTs (4/31; 13%), MPNSTs (2/35; 6%), and SSs (1/25; 4%). Within the collection of sarcoma cell lines examined, TERT promoter mutations were detected in two MLS and in one of three MPNST cell lines. TERT promoter mutations are frequent in MLSs including their round cell variants, representing the most prevalent mutation identified in this sarcoma entity to date, and in a minor fraction of SFTs, MPNSTs and SSs. The majority of sarcomas are devoid of TERT promoter hotspot mutations. These data suggest that telomere maintenance through increased expression of telomerase plays an important role in the pathogenesis especially of MLS.

20 October 2014 in Journal of Clinical Oncology
Verified
Journal Article
Closed access
TSThomas Schmitt
Thomas Schmitt
HGHartmut Goldschmidt
Hartmut Goldschmidt
KNKai Neben
Kai Neben
AFAnja Freiberger
Anja Freiberger
JHJohannes Hüsing
Johannes Hüsing
GEGerlinde Egerer
Gerlinde Egerer
Purpose: The optimal regimen to prevent chemotherapy-induced nausea and vomiting (CINV) for patients undergoing high-dose chemotherapy and autologous stem-cell transplantation (ASCT) is unclear. To evaluate the effect of aprepitant in addition to a standard regimen, we conducted this randomized, placebo-controlled phase III trial. Patients and Methods: Patients with multiple myeloma were randomly assigned at a one-to-one ratio to receive either aprepitant (125 mg orally on day 1 and 80 mg orally on days 2 to 4), granisetron (2 mg orally on days 1 to 4), and dexamethasone (4 mg orally on day 1 and 2 mg orally on days 2 to 3) or matching placebo, granisetron (2 mg orally on days 1 to 4), and dexamethasone (8 mg orally on day 1 and 4 mg orally on days 2 to 3). Melphalan 100 mg/m2 was administered intravenously on days 1 to 2. ASCT was performed on day 4. The primary end point (complete response) was defined as no emesis and no rescue therapy within 120 hours of melphalan administration. Quality of life was assessed by modified Functional Living Index–Emesis (FLIE) questionnaire on days −1 and 6. Results: Overall, 362 patients were available for the efficacy analysis (181 in each treatment arm). Significantly more patients receiving aprepitant reached the primary end point (58% v 41%; odds ratio [OR], 1.92; 95% CI, 1.23 to 3.00; P = .0042). Absence of major nausea (94% v 88%; OR, 2.37; 95% CI, 1.09 to 5.15; P = .026) and emesis (78% v 65%; OR, 1.99; 95% CI, 1.25 to 3.18; P = .0036) within 120 hours was increased by aprepitant. Mean total FLIE score (± standard deviation) was 114 ± 18 for aprepitant and 106 ± 26 for placebo (P < .001). Conclusion: The addition of aprepitant resulted in significantly less CINV and had a positive effect on quality of life.

20 May 2014 in BMC Cancer
Verified
Journal Article
Open access
PDF file
FRFalk Roeder
Falk Roeder
BLBurkhard Lehner
Burkhard Lehner
TSThomas Schmitt
Thomas Schmitt
Bernd KasperBernd Kasper
Bernd Kasper
GEGerlinde Egerer
Gerlinde Egerer
MBMarc Bischof
Marc Bischof
To report the results of a subgroup analysis of a prospective phase II trial focussing on radiation therapy and outcome in patients with extremity soft tissue sarcomas (STS).

21 June 2010 in Bone Marrow Transplantation
Verified
Journal Article
Closed access
TSThomas Schmitt
Thomas Schmitt
TLT Luft
T Luft
UHU Hegenbart
U Hegenbart
TTT H Tran
T H Tran
AHA D Ho
A D Ho
PDP Dreger
P Dreger

7 December 2011 in BMC Cancer
Verified
Journal Article
Open access
PDF file
TSThomas Schmitt
Thomas Schmitt
BLBurkhard Lehner
Burkhard Lehner
Bernd KasperBernd Kasper
Bernd Kasper
MBMarc Bischof
Marc Bischof
FRFalk Roeder
Falk Roeder
GEGerlinde Egerer
Gerlinde Egerer
The role of chemotherapy in high-risk soft tissue sarcoma is controversial. Though many patients undergo initial curative resection, distant metastasis is a frequent event, resulting in 5-year overall survival rates of only 50-60%. Neo-adjuvant and adjuvant chemotherapy (CTX) has been applied to achieve pre-operative cytoreduction, assess chemosensitivity, and to eliminate occult metastasis. Here we report on the results of our non-randomized phase II study on neo-adjuvant treatment for high-risk STS.