Circulating cell-free DNA fragmentation is a stepwise and conserved process linked to apoptosis.

BACKGROUND: Circulating cell-free DNA (cfDNA) is a pool of short DNA fragments mainly released from apoptotic hematopoietic cells. Nevertheless, the precise physiological process governing the DNA fragmentation and molecular profile of cfDNA remains obscure. To dissect the DNA fragmentation process, we use a human leukemia cell line HL60 undergoing apoptosis to analyze the size distribution of DNA fragments by shallow whole-genome sequencing (sWGS). Meanwhile, we also scrutinize the size profile of plasma cfDNA in 901 healthy human subjects and 38 dogs, as well as 438 patients with six common cancer types by sWGS. RESULTS: Distinct size distribution profiles were observed in the HL60 cell pellet and supernatant, suggesting fragmentation is a stepwise process. Meanwhile, C-end preference was seen in both intracellular and extracellular cfDNA fragments. Moreover, the cfDNA profiles are characteristic and conserved across mammals. Compared with healthy subjects, distinct cfDNA profiles with a higher proportion of short fragments and lower C-end preference were found in cancer patients. CONCLUSIONS: Our study provides new insight into fragmentomics of circulating cfDNA processing, which will be useful for early diagnosis of cancer and surveillance during cancer progression.

Relationship Between SLC22A1 and SLC22A4 Gene Polymorphisms and Risk of Type 2 Diabetes in Chinese Han Population.

BACKGROUND: This study was to investigate the relationship between SLC22A1 and SLC22A4 gene polymorphisms and genetic susceptibility to type 2 diabetes in Chinese Han population. METHODS: The research group comprised 110 Chinese Han patients with type 2 diabetes, and the control group included 110 healthy volunteers. The polymorphisms of SLC22A1 gene rs628031 and rs2282143 loci and SLC22A4 gene rs2073838 and rs272893 loci were detected in the two groups. RESULTS: Statistically significant differences were identified in the genotype distributions of SLC22A1 gene rs628031 and rs2282143 loci between the two groups (p < 0.05). The A allele frequency of SLC22A1 gene rs628031 locus and the T allele frequency of rs2282143 locus were higher in the research group than in the control group (p < 0.05). The genotype distributions of rs272893 locus showed a significant difference between the two groups (p < 0.05), but not SLC22A4 gene rs2073838 locus (p > 0.05). CONCLUSIONS: The polymorphisms of SLC22A1 gene rs628031 and rs2282143 loci and SLC22A4 gene rs272893 locus of patients with type 2 diabetes indicated a significant difference between the two groups, suggesting that these genetic locus mutations increase the risk of type 2 diabetes in Chinese Han patients.

Noninvasive Detection of Hepatocellular Carcinoma with Circulating Tumor DNA Features and α-Fetoprotein.

Liver cancer is the fifth-most common cancer worldwide, with the third-highest rate of cancer-related mortality. Hepatocellular carcinoma (HCC) is the leading pathologic subtype, contributing 85% to 90% of cases of primary liver cancer. Most HCC patients are diagnosed at an advanced stage at which treatment is not curative. This study assessed the performance of a newly developed blood-based assay that utilizes genomic features and protein markers for the early detection of HCC. Two cancer-associated hallmarks, copy-number aberrations (CNA) and fragment size (FS), were characterized by shallow whole-genome sequencing of cell-free DNA and utilized to differentiate cancer patients from healthy subjects. As a clinically implemented biomarker of HCC, plasma α-fetoprotein (AFP) was also used with the genomic surrogates to optimize the detection of HCCs. The sensitivity of AFP ≥20.0 µg/L in detecting HCC was 57.9%. The combined genomic classifier CNA + FS via cell-free DNA shallow whole-genome sequencing identified nearly half of AFP-negative HCC patients (43.8%). By integrating CNA, FS as well as AFP (HCCseek), 75.0% sensitivity was achieved at 98.0% specificity, resulting in 92.6% accuracy, with 58.6% sensitivity in stage I HCC. The quantitative output of HCCseek was correlated with the severity of the disease (tumor size, stage, and recurrence-free survival). In summary, this study describes an efficient, noninvasive, and cost-effective method to detect HCC.

Primary Extracranial Meningioma of Mastoid in a Patient With History of Skin Squamous Cell Carcinoma, Lung Adenocarcinoma and Prostatic Carcinoma.

BACKGROUND: Meningiomas are the most common benign intracranial tumors and frequently develop in the parasagittal region, but can also present extracranially. Rarely, meningiomas may involve the middle ear and mastoid, resulting from contiguous spread of adjacent intracranial tumor, or extremely rarely, as an isolated primary tumor, which is frequently misdiagnosed and unrecognized, resulting in inappropriate clinical management. CASE REPORT: Herein we report such a case of an 80-year-old man with history of multiple cancer who presented with ear pain, vertigo and hearing loss. Audiometry demonstrated bilateral sensorineural hearing loss. Contrast-enhanced temporal bone computed tomography revealed a soft-tissue mass in the right epitympanum without bone erosion or any intracranial involvement. Radiological and operative findings were suspicious for cholesteatoma. Histological examination showed an epithelial neoplasm arranged in nests and whorls with intranuclear inclusions. No psammoma bodies, mitotic figures, or tumor necrosis were identified. The tumor cells were positive for epithelial membrane antigen, vimentin, progesterone receptor and CD56; and negative for synaptophysin, chromogranin, pancytokeratin (AE1/AE3), cytokeratin 7, prostate-specific antigen, inhibin, S100, P63, and P40. Ki67 highlighted about 2% of the tumor cells. Based on the morphological features and immunohistochemical profile, the tumor was diagnosed as primary extracranial meningioma of the mastoid, meningothelial subtype, World Health Organization grade 1. CONCLUSION: To the best of our knowledge, primary mastoid meningioma clinically mimicking a cholesteatoma presenting in a patient with a history of multiple primary carcinomas has not been previously reported. The pathogenesis, diagnosis and treatment of this entity are discussed.

Cotransplantation of Mesenchymal Stem Cells and Immature Dendritic Cells Potentiates the Blood Glucose Control of Islet Allografts.

BACKGROUND: Transplantation of islets is a promising alternative to treat type 1 diabetes (T1D), but graft rejection is the major obstacle to its application in clinical practice. We evaluated the effects of mesenchymal stem cells (MSCs) and immature dendritic cells (imDCs) on islet transplantation in diabetic model. METHODS: The streptozotocin T1D model was established in BABL/c mice. Rat islets were isolated and identified with dithizone (DTZ) staining. MSCs and imDCs were isolated from bone marrow of syngenic mice. Islets, alone or along with MSCs and/or imDCs, were transplanted to the left kidney capsule of diabetic mice. The blood glucose levels and glycosylated hemoglobin levels after transplantation were monitored. RESULTS: Cotransplantation significantly decreased blood glucose and glycosylated hemoglobin levels in the diabetes mice. Transplantation of 200 islets + 2 × 105 MSCs + 2 × 105 imDCs could not only restore normal blood glucose levels, but also significantly prolong graft survival for 12.6 ± 3.48 days. CONCLUSIONS: Cotransplantation of allogenic islets with imDCs and/or MSCs can significantly promote graft survival, reverse hyperglycemia, and effectively control the glycosylated hemoglobin levels.