Neoplasms

All Conditions

Symptoms and General Pathology

Skin and Connective Tissue Diseases

Rare Diseases

Osteosarcoma

Necrosis

Disease Progression

Neoplasms, Bone Tissue

Neoplasms, Connective Tissue

Neoplasms, Connective and Soft Tissue

Neoplasms by Histologic Type

Sarcoma

Soft Tissue Sarcoma

One group of participants are under observation. This trial has two phase. Phase I: 40 participants will be enrolled. Only if epigenetic cfDNA library has been built, investigators would move on to Phase II. Another 60 participants will be enrolled for further analysis.

Lu Xie, M.D.

Jie Xu, M.D

Tingting Ren, Ph.D.

Wei Guo, M.D.and Ph.D.

hMe-Seal is a low-input whole-genome cell-free 5hmC sequencing method based on selective chemical labeling. It uses β-glucosyltransferase (βGT) to selectively label 5hmC with a biotin via an azide-modified glucose for pull-down of 5hmC-containing DNA fragments for sequencing. After selectively constructing 5hmC library, highthroughput-sequencing will be performed on an Illumina Nextseq-500 instrument. By ways of Rawdata processing, differential loci between Osteosarcoma group and control group will be detected to indentify specific epigenetic biomarkers of Osteosarcoma.

The investigator want to enroll 100 osteosarcoma participants initially treated in Musculoskeletal Tumor Center of Peking University People's Hospital(PKUPH). All those participants will follow the chemo-protocol for osteosarcoma in PKUPH.8 ml of peripheral blood would be drawed before each cycle of chemotherapy for further analysis. After definitive surgery, participants will need to take 8ml of peripheral blood every 2 months for 6 months. A total of 6 times of blood drawing will need to be done.

In hMe-Seal approach, peripheral blood is collected into EDTA-coated Vacutainers. Plasma is collected from the blood samples after centrifugation at 1 600× g for 10 min at 4 °C and 16 000× g at 10 min at 4 °C. CfDNA is extracted using the Circulating Nucleic Acid Kit(QIAGEN). After that, cfDNA (1-10 ng) is end repaired, 3'-adenylated and ligated to DNA Barcodes using KAPA Hyper Prep Kit (Kapa Biosystems). Ligated DNA is incubated in a solution containing HEPES buffer, UDP-6-N3-Glc and βGT . After that, DBCO-PEG4-biotin is directly added to the reaction mixture. Next, DNA is purified by Micro Bio-Spin 30 Column (Bio-Rad). The purified DNA is incubated with M270 Streptavidin beads (Life Technologies) in specific buffer. The beads are subsequently undergone three 5-min washes each with four kinds of different buffers. All binding and washing are done at room temperature with gentle rotation. Beads are then resuspended in water and amplified with 16 cycles of PCR amplification. The PCR products are purified using AMPure XP beads. Pair-end 38bp sequencing is performed on the NextSeq-500 instrument.

Peripheral blood with enough free DNA should be segregation. If the peripheral blood is not taken properly, it should be disposed of it or blood should be drawn again for DNA amplication and analysis.

Epigenetic Biomarker for Osteosarcoma

Indentifying Epigenetic Biomarkers From Peripheral Blood of Osteosarcoma Patients Based on hMe-Seal Technique

The investigators of this study would like to share IPD. However other cooperative institution's consent will be needed for sharing IPD.

For osteosarcoma, tumor necrosis rate will be done for every participant. On pathologic examination, the surgical specimens were carefully studied and sectioned. This evaluation included establishing the gross extent of the tumor\[26, 27\] and noting its soft tissue component and lines of surgical resection\[27\]. An average of 10-20 histologic specimens were examined in each of the en bloc resections to delineate the extension of osteosarcoma up and down the marrow cavity and to study the effects of chemotherapy on the tumor (viable, partially, largely, or totally necrotic), which were then calculated as tumor necrosis rate as paper described.

According to RECIST 1.1, participants who meet the criteria of complete response and partial response.

Progression-free survival (PFS) will be calculated from the start of chemotherapy to first progression.

Overall survival (OS) will be calculated from the start of chemotherapy to death.

Spots Global Cancer Trial Database for objective response rate for neoadjuvant chemotherapy, orr