Proteomic characterization identifies clinically relevant subgroups of soft tissue sarcoma.

Soft tissue sarcoma is a broad family of mesenchymal malignancies exhibiting remarkable histological diversity. We portray the proteomic landscape of 272 soft tissue sarcomas representing 12 major subtypes. Hierarchical classification finds the similarity of proteomic features between angiosarcoma and epithelial sarcoma, and elevated expression of SHC1 in AS and ES is correlated with poor prognosis. Moreover, proteomic clustering classifies patients of soft tissue sarcoma into 3 proteomic clusters with diverse driven pathways and clinical outcomes. In the proteomic cluster featured with the high cell proliferation rate, APEX1 and NPM1 are found to promote cell proliferation and drive the progression of cancer cells. The classification based on immune signatures defines three immune subtypes with distinctive tumor microenvironments. Further analysis illustrates the potential association between immune evasion markers (PD-L1 and CD80) and tumor metastasis in soft tissue sarcoma. Overall, this analysis uncovers sarcoma-type-specific changes in proteins, providing insights about relationships of soft tissue sarcoma.

[Screening of differentially expressed microRNAs in borderline and malignant gastrointestinal stromal tumors].

OBJECTIVE: Gastrointestinal stromal tumors (GISTs) have a broad spectrum of biological behaviors ranging from benign, borderline and malignant. This study aimed to screen differentially expressed microRNAs (miRNAs) between malignant and borderline GISTs and to investigate the potential role of miRNAs in the malignant transformation of GISTs. METHODS: Six GIST samples including borderline tumors (n = 3) and malignant tumors (n = 3) were collected based on the clinical and pathological characteristics. Total RNA was extracted, followed by miRNA microarray analysis to screen the differentially expressed miRNAs. The most significantly expressed 4 miRNAs were then chosen for further validation by real-time PCR in 22 additional GIST samples. RESULTS: Direct comparison of malignant group versus borderline group revealed 14 significantly and differentially expressed miRNAs (P < 0.05, with a fold change of < 0.5 or > 2). Five miRNAs were up-regulated and nine were down-regulated in the malignant group. Four miRNAs (miR-221, miR-135b, miR-675(*) and miR-218) were most significantly and differentially expressed between the two groups. The differential expression of 2 miRNAs (miR-221 and miR-675(*)) were subsequently confirmed with good concordance by real-time PCR. CONCLUSIONS: The differential miRNA expression profiles between two groups are revealed by miRNA microarray assay, and confirmed by real-time PCR. Among differentially expressed miRNAs, miR-221 and miR-675(*) might be related to the malignant transformation of GISTs, and have a potential value in predicting biological behavior of GISTs.

Therapy-related acute myeloid leukemia in a primary pulmonary leiomyosarcoma patient with skin metastasis.

Primary pulmonary leiomyosarcoma (LMS) is a very unusual tumor. Although LMS has well-known metastatic potential, cutaneous metastasis is a remarkably uncommon. Exposure to cytotoxic agents could lead to "therapy-related myeloid neoplasm" (t-MN). Starting from 2008, the World Health Organization (WHO) has adopted the term to cover the spectrum of malignant diseases previously known as therapy-related acute myeloid leukemia (t-AML), therapy-related myelodysplastic syndrome (t-MDS) and therapy-related myelodysplastic/myelo- proliferative neoplasm (t-MDS/MPN). We described the onset of t-MDS and progression to t-AML in one case diagnosed as primary pulmonary LMS with cutaneous metastasis. This patient achieved complete remission (CR) after three courses of IA regimen chemotherapy (idarubicin 5 mg/d, d 1-3; cytarabine 100 mg/d, d 1-5) and 1 course of HA chemotherapy regimen (homoharringtonine 3 mg/d, d 1-3; cytarabine 100 mg/d, d 1-7). This case presents the natural course of therapy-related neoplasm and provides therapeutic experience for t-AML.

The use of mutation-specific antibodies in predicting the effect of EGFR-TKIs in patients with non-small-cell lung cancer.

PURPOSE: We aimed to quantify the epidermal growth factor receptor (EGFR) mutation in tumors and to analyze its prediction of EGFR-tyrosine kinase inhibitor (EGFR-TKI) treatment efficacy in EGFR mutation-positive non-small-cell lung cancer (NSCLC) patients. METHODS: We examined EGFR mutation status in 124 lung cancer samples by direct sequencing and amplification refractory mutation system. Among them, 41 were appropriate to quantify the expression of mutant EGFR proteins using immunohistochemistry (IHC) with mutation-specific antibodies. The quantification was determined by both the staining intensity and the proportion of stained tumor cells. RESULTS: The median progression-free survival (PFS) in patients with a high score for mutant EGFR expression was 18.0 months (95 % CI 16.0-20.0), which was significantly longer than that in patients with a low score (8.0 months; 95 % CI 2.6-13.4; P = 0.048). Such significant association with patients' PFS was also apparent in the proportion of stained tumor cells (median, 19.0 vs. 8.0 months; P = 0.019), but not in the staining intensity (P = 0.787). Among the 41 specimens, 32 were detected EGFR mutation positive by both direct sequencing and ARMS, referring to a relatively high abundance of mutation, and 26 (81.3 %) of them gained a high expression score of mutant proteins as well. Six samples with mutation negative by direct sequencing but positive by ARMS, which showed a low abundance, and 5 (83.3 %) of them also revealed a low expression score. The EGFR mutation quantitative analysis using mutation-specific IHC was moderately consistent with that by molecular-based assays (P = 0.001, kappa value 0.50). CONCLUSIONS: Our results suggest that immunohistochemical analysis with mutation-specific antibodies is a promising approach for quantifying EGFR mutations, and may predict the effect of EGFR-TKI treatment for EGFR mutation-positive NSCLC.