[Effects and mechanism of glycine on rat cardiomyocytes pretreated with serum from burned rats].

Objective: To investigate the effect and mechanism of glycine on rat cardiomyocytes pretreated with serum from burned rats (hereinafter referred to as burn serum). Methods: Experimental research methods were adopted. Thirty gender equally balanced Wistar rats aged 7 to 8 weeks were collected, 10 of which were used to prepare normal rat serum (hereinafter referred to as normal serum), and the other 20 were inflicted with full-thickness burn of 30% total body surface area to prepare burn serum. Primary cardiomyocytes were isolated and cultured from the apical tissue of 180 Wistar rats aged 1 to 3 days by either gender for follow-up experiments. Cells were divided into normal serum group and burn serum group treated with corresponding serum according to the random number table (the same grouping method below). Trypanosoma blue staining was performed at post treatment hour (PTH) 1, 3, 6, 9, and 12 to detect the cell survival rate. Cells were divided into burn serum alone group treated with burn serum for 6 h followed by routine culture of 30 min and 0.4 mmol/L glycine group, 0.8 mmol/L glycine group, 1.2 mmol/L glycine group, 1.6 mmol/L glycine group, and 2.0 mmol/L glycine group treated with burn serum for 6 h followed by culture of 30 min with corresponding final molarity of glycine, i.e., at post intervention hour (PIH) 6.5, the cell survival rate was detected as before. Cells were divided into normal serum group, burn serum alone group, 0.8 mmol/L glycine group, 1.2 mmol/L glycine group, and 1.6 mmol/L glycine group, with the same intervention of 6.5 h as before, respectively. The content of adenosine monophosphate (AMP) and adenosine triphosphate (ATP) was detected by high performance liquid chromatography, and the AMP/ATP ratio was calculated. The protein expressions of phosphorylated mammalian target of rapamycin complex 1 (p-mTORC1), phosphorylated p70 ribosomal protein S6 kinase (p-p70 S6K), phosphorylated eukaryotic translation initiation factor 4E-binding protein 1 (p-4E-BP1), and phosphorylated AMP-activated protein kinase (p-AMPK) were detected by Western blotting. Cells were divided into normal serum group, burn serum alone group, 0.8 mmol/L glycine group intervened as before and 0.8 mmol/L glycine+25 ng/mL rapamycin group treated with burn serum followed by culture with two reagents. The expressions of heat shock protein 70 (HSP70), metallothionein (MT), and tubulin were detected by immunofluorescence method after 30 min of corresponding culture at PTH 1, 3, and 6, i.e., at PIH 1.5, 3.5, and 6.5, and the microtubule morphology was observed at PIH 6.5. The sample number at each time point was 10. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, least significant difference (LSD)-t test, LSD test, and Bonferroni correction. Results: At PTH 1, 3, 6, 9, and 12, the cell survival rates in burn serum group were significantly lower than those in normal serum group (with t values of 4.96, 16.83, 35.51, 34.33, and 27.88, P<0.05). In burn serum group, the cell survival rate at PTH 3, 6, 9, or 12 was significantly lower than that at PTH 1 (P<0.05), the cell survival rate at PTH 6, 9, or 12 was significantly lower than that at PTH 3 (P<0.05), and the cell survival rate at PTH 6 was similar to that at PTH 9 (P>0.05) but significantly higher than that at PTH 12 (P<0.05). Treatment of 6 h was selected as the follow-up intervention time of burn serum. At PIH 6.5, compared with that in burn serum alone group, the cell survival rate in each glycine group was significantly increased (P<0.05). The cell survival rate in 0.8 mmol/L glycine group was the highest, and 0.8, 1.2, and 1.6 mmol/L were selected as subsequent glycine intervention concentrations. At PIH 6.5, the AMP/ATP ratio of cells in burn serum alone group was significantly higher than that in normal serum group, 1.2 mmol/L glycine group, or 1.6 mmol/L glycine group (P values all <0.05), and the AMP/ATP ratio of cells in 1.6 mmol/L glycine group was significantly lower than that in 0.8 mmol/L glycine group (P<0.05). At PIH 6.5, the protein expressions of p-mTORC1, p-p70 S6K, and p-4E-BP1 of cells in normal serum group, burn serum alone group, 0.8 mmol/L glycine group, 1.2 mmol/L glycine group, and 1.6 mmol/L glycine group were 1.001±0.037, 0.368±0.020, 1.153±0.019, 1.128±0.062, 1.028±0.037, 0.96±0.07, 0.63±0.12, 1.17±0.13, 1.13±0.16, 1.11±0.11, and 0.98±0.06, 0.45±0.08, 1.13±0.05, 0.77±0.12, 0.51±0.13. Compared with those in burn serum alone group, the protein expressions of p-mTORC1, p-p70 S6K, and p-4E-BP1 of cells in normal serum group and each glycine group were significantly increased (P<0.05), while the protein expressions of p-AMPK were significantly decreased (P<0.05). Compared with those in 0.8 mmol/L glycine group, the protein expression of p-4E-BP1 of cells in 1.2 mmol/L glycine group and the protein expressions of p-mTORC1 and p-4E-BP1 of cells in 1.6 mmol/L glycine group were significantly decreased (P<0.05). Compared with those in 1.2 mmol/L glycine group, the protein expressions of p-mTORC1 and p-4E-BP1 of cells in 1.6 mmol/L glycine group were significantly decreased (P<0.05), while the protein expression of p-AMPK was significantly increased (P<0.05). Compared with those in normal serum group, the expression of tubulin of cells in burn serum alone group was significantly decreased at PIH 1.5, 3.5, and 6.5 (P<0.05), while the expression of HSP70 of cells at PIH 1.5 and 3.5 and the expression of MT at PIH 3.5 and 6.5 were significantly increased (P<0.05). The expressions of HSP70 and MT of cells at PIH 1.5, 3.5, and 6.5 and the expression of tubulin at PIH 1.5 and 3.5 in burn serum alone group and 0.8 mmol/L glycine+25 ng/mL rapamycin group were significantly lower than those in 0.8 mmol/L glycine group (P<0.05). At PIH 6.5, compared with that in normal serum group, the cell microtubule structure in burn serum alone group was disordered; the cell boundary in 0.8 mmol/L glycine group was clearer than that in burn serum alone group, and the microtubule structure arranged neatly near the nucleus. Compared with that in 0.8 mmol/L glycine group, 0.8 mmol/L glycine+25 ng/mL rapamycin group had unclear cell boundaries and disordered microtubule structure. Conclusions: Burn serum can cause cardiomyocytes damage in rats. Glycine can significantly up-regulate mammalian target of rapamycin/p70 ribosomal protein S6 kinase/eukaryotic translation initiation factor 4E-binding protein 1 signaling pathway through AMP-activated protein kinase, promote the synthesis of protective proteins HSP70, MT, and tubulin, stabilize the microtubule structure, and exert cardiomyocytes protection function.

[Application of temporalis muscle flap in repair and reconstruction after the resection of tumor or necrotic foci following radiotherapy of nasopharyngeal carcinoma].

Objective: To summarize and popularize the application of temporalis muscle flap in repair and reconstruction after the resection of tumor or necrotic foci following radiotherapy of nasopharyngeal carcinoma (NPC). Methods: A retrospective analysis was made on the patients treated in the Department of Otorhinolaryngology Head and Neck Surgery of Xiangya Hospital between January 2019 and March 2021 who underwent surgical resection of tumor or necrosis of NPC after radiotherapy and temporalis muscle flap repair. The effect of the repair and the patients' postoperative conditions were analyzed. Results: A total 29 patients, 19 males and 10 females, aged from 33 to 65 years old, were included in the study, and were followed up for 6-35 months. Except for 2 patients who were not followed due to bleeding or special bacterial infection, the others' temporalis muscle flap healed well and no cerebrospinal fluid rhinorrhea or massive hemorrhage occurred. After the operation, all patients had no nasopharyngeal reflux or new open rhinolalia, and in some patients, the open rhinolalia even got relieved. Except for one case of depressed temporal fossa caused by infection and followed debridement and another one case of shallowed forehead wrinkles, the appearances of the other patients were basically symmetrical. Some patients had temporary mouth opening limitation after operation, and all of them recovered after rehabilitation exercises. Conclusions: The temporalis muscle flap can protect the skull base and internal carotid artery, and improve the quality of life of patients after the resection of NPC or necrotic foci. It is a reliable pedicled flap for repairing skull base defect with simple operation procedures and relatively few complications.

[Effects and cell signaling mechanism of glutamine on rat cardiomyocytes intervened with serum from burned rat].

Objective: To investigate the effects and cell signaling mechanism of glutamine on rat cardiomyocytes intervened with serum from burned rat (hereinafter referred to as burn serum). Methods: The experimental research method was applied. Ten gender equally distributed Wistar rats aged 7-8 months were taken to prepare normal rat serum (hereinafter referred to as normal serum), another twenty gender equally distributed Wistar rats aged 7-8 months were taken to prepare burn serum after full- thickness burn injury of 30% total body surface area, and primary cardiomyocytes were isolated and cultured from 180 Wistar rats aged 1-3 days by either gender and used in the following experiments. The cells were divided into normal serum group and burn serum group according to the random number table (the same grouping method below) and cultured with the corresponding serum. At post culture hour (PCH) 1, 3, 6, 9, and 12, trypanosoma blue test was used to detect the cell survival rate. The cells were divided into burn serum alone group, burn serum+4 mmol/L glutamine group, burn serum+8 mmol/L glutamine group, burn serum+12 mmol/L glutamine group, burn serum+16 mmol/L glutamine group, and burn serum+20 mmol/L glutamine group, which were treated with burn serum alone or burn serum added with the corresponding final molarity of glutamine and cultured for the time screened in the experiment before, and then the cell survival rate was detected as before. The cells were divided into normal serum group, burn serum alone group, burn serum+12 mmol/L glutamine group, burn serum+16 mmol/L glutamine group, and burn serum+20 mmol/L glutamine group and treated the same as before. After 30 min of culture, phosphorylation levels of mammalian target of rapamycin complex 1 (mTORC1), p70 ribosomal protein S6 kinase (p70 S6K), and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) were detected by Western blotting. Cells were divided into normal serum group, burn serum alone group, burn serum+12 mmol/L glutamine group, burn serum+12 mmol/L glutamine+25 ng/mL rapamycin group, and treated correspondingly. At PCH 1, 3, and 6, the expressions of heat shock protein 70 (HSP70) and metallothionein (MT), and the morphology of microtubule were determined with immunofluorescence method. The sample numbers in each index at each time point in each group were all 10. Data were statistically analyzed with analysis of variance for factorial design, one-way analysis of variance, least significant difference t test, least significant difference test, and Bonferroni correction. Results: At PCH 1, 3, 6, 9, and 12, the cell survival rates in burn serum group were significantly lower than those in normal serum group (t=4.950, 16.752, 35.484, 34.428, 27.781, P<0.01). Compared within the group at PCH 1, the cell survival rate was significantly decreased in burn serum group at PCH 3, 6, 9, and 12 (P<0.05). Compared within the group at PCH 3, the cell survival rate was significantly decreased in burn serum group at PCH 6, 9, and 12 (P<0.05). Compared within the group at PCH 6 and 9, the cell survival rate was significantly decreased in burn serum group at PCH 12 (P<0.05). There were no statistically significant differences in the cell survival rates in burn serum group between PCH 6 and 9 (P>0.05). Thus PCH 6 was selected as the subsequent intervention time of burn serum. At PCH 6, compared with burn serum alone group, the cell survival rates in burn serum+4 mmol/L glutamine group, burn serum+8 mmol/L glutamine group, burn serum+12 mmol/L glutamine group, burn serum+16 mmol/L glutamine group, and burn serum+20 mmol/L glutamine group were significantly increased (P<0.01). There were no statistically significant differences in cell survival rates between burn serum+12 mmol/L glutamine group and burn serum+16 mmol/L glutamine group (P>0.05). There were no statistically significant differences in cell survival rates in burn serum+16 mmol/L glutamine group and burn serum+20 mmol/L glutamine group (P>0.05). Thus 12, 16, and 20 mmol/L were selected as the subsequent intervention concentrations of glutamine. After 30 min of culture, the phosphorylation levels of mTORC1, p70 S6K, and 4E-BP1 of cells were respectively 1.001±0.042, 0.510±0.024, 0.876±0.022, 0.836±0.074, 0.856±0.041, 1.00±0.11, 0.38±0.09, 0.95±0.13, 0.96±0.13, 0.89±0.24, 1.00±0.07, 0.29±0.08, 0.87±0.27, 0.68±0.08, 0.60±0.21 in normal serum group, burn serum alone group, burn serum+12 mmol/L glutamine group, burn serum+16 mmol/L glutamine group, and burn serum+20 mmol/L glutamine group. Compared with normal serum group, the phosphorylation levels of mTORC1, p70 S6K, and 4E-BP1 of cells were significantly decreased in the other 4 burn serum groups (P<0.01). Compared with those of burn serum alone group, the phosphorylation levels of mTORC1, p70 S6K, and 4E-BP1 of cells were significantly increased in the other 3 burn serum groups (P<0.01). The phosphorylation level of 4E-BP1 of cells in burn serum+12 mmol/L glutamine group was significantly higher than the levels in burn serum+16 mmol/L glutamine group and burn serum+20 mmol/L glutamine group (P<0.05). The expression of MT of cells in burn serum alone group was significantly lower than that in normal serum group at PCH 1 (P<0.05), while the expressions of MT of cells in burn serum alone group were significantly higher than those in normal serum group at the other time points (P<0.05). At PCH 1, 3, and 6, the expressions of HSP70 of cells in burn serum alone group were significantly higher than those in normal serum group (P<0.05), the expressions of HSP70 and MT of cells in burn serum+12 mmol/L glutamine group were significantly higher than those in burn serum alone group (P<0.05), and the expressions of HSP70 and MT of cells in burn serum+12 mmol/L glutamine+25 ng/mL rapamycin group were significantly lower than those in burn serum+12 mmol/L glutamine group (P<0.01). The microtubular structures were intact, displaying grid alinement and uniform staining in cells of normal serum group at PCH 1, 3, and 6. In burn serum alone group, some microtubules showed fracture and irregular grid arrangement at PCH 1; the microtubular structures near the nucleus were clear, while the microtubules at the distal end of the nucleus were blurry at PCH 3; the microtubular structures were blurry at PCH 6. The microtubular damage of cells was alleviated in burn serum+12 mmol/L glutamine group as compared with that in burn serum alone group at each time point of culture. The morphology of microtubules of cells in burn serum+12 mmol/L glutamine+25 ng/mL rapamycin group at each time point of culture was similar to that of burn serum alone group. Conclusions: The burn serum can lead to damages to cardiomyocytes and significant decrease of cell survival rate in rats. Glutamine can exert cell protective function through the regulation of mTOR/p70 S6K/4E-BP1 signaling pathway, thus promoting the expressions of HSP70 and MT and stabilizing the microtubule structures.

[Clinical study on endoscopic surgery for soft tissue necrosis of cranial base after radiotherapy for nasopharyngeal carcinoma].

Objective: To investigate the diagnosis and surgical treatment of patients with soft tissue necrosis of cranial base after radiotherapy for nasopharyngeal carcinoma (NPC). Methods: The clinical data of 7 NPC patients with soft tissue necrosis but not bone necrosis after radiotherapy were retrospectively analyzed.They were treated in Xiangya Hospital from 2015 to 2019. The clinical manifestations, diagnosis, treatment and prognosis were analyzed. The major clinical symptoms of the 7 patients were headache in 7 cases, hearing loss in 7 cases, long-term nasal malodor in 5 cases and epistaxis in 2 cases. All patients underwent high-resolution CT, MR and magnetic resonance angiography (MRA) before operation. All cases were treated with extended transnasal endoscopic approach under general anesthesia for resection of necrotic tissue. Five cases had their affected cartilaginous segments of the eustachian tubes partially or completely resected, 7 cases were treated with myringotomy and tube insertion, and 1 case was treated with pansinusectomy. Anti-inflammatory treatment were carried out during the perioperative period. The recovery of patients was observed and recorded through regular follow-up (from 6 months to 3 years) after the operation. Results: Nasopharynx soft tissue lesions can be seen in seven patients with bone cortex integrity by CT, and small bubble shadow can be seen at junction area between skull base soft tissue lesions and skull base bone surface.MR and MRA examination showed extensive inflammatory changes of nasopharynx. Parapharyngeal irregular necrotic cavity was found in 6 cases without central enhancement, demonstrating edema of surrounding soft tissue. The necrotic tissue of all 7 patients was surgically removed. Postoperative pathological examinations confirmed that all of them were necrotic soft and cartilaginous tissue, without tumor recurrence. The symptoms of all patients were significantly alleviated after operation. Headache was cured in 5 cases and relieved in 2 cases. Nasal malodor was cured in 4 cases and alleviated in 1 case. During the follow-up period, 5 patients survived, and 2 patients who had their eustachian tube reserved died. One of them died of nasopharyngeal hemorrhage caused by recurrent nasopharyngeal necrosis 3 months after the operation. Another case died of severe intracranial infection 6 months after operation. Conclusions: The diagnosis of skull base soft tissue necrosis after radiotherapy for nasopharyngeal carcinoma needs comprehensive analysis of radiotherapy history, clinical manifestations and imaging examination. High resolution CT, MR and MRA of skull base are very important for diagnosis. Early active removal of large-scale necrotic lesions under endoscope and partial or total resection of eustachian tube cartilage according to the involvement of eustachian tube cartilage is effective means of controling skull base soft tissue necrosis after radiotherapy. The effective means of necrosis can improve the quality of life of patients.

[Application and clinical study of clonal heterogeneity analysis in acute myeloid leukemia].

Objective: This study aimed to explore the characteristics and clinical value of clonal heterogeneity in acute myeloid leukemia (AML) . Method: A high-throughput sequencing was carried out to detect 68 related genes in 465 AML patients. Clonal heterogeneity was analyzed based on variant allele frequency (VAF) and flow cytometry results combined with clinical data. Results: Gene mutations were discovered in 338 (81.4%) newly diagnosed patients, and 2 or more clones were significantly increased in patients with DNMT3A, NRAS, and RUNX1 mutations (DNMT3A, χ(2)=15.23; P<0.001; NRAS, χ(2)=19.866; P<0.001; RUNX1, χ(2)=23.647; P<0.001) . The number of clones significantly differed between groups at different ages (χ(2)=17.505, P=0.022) . The proportion of carrying 2 and ≥3 clones increased in patients aged more than 60 years old. There was a significant difference in the clonal heterogeneity between newly diagnosed patients and relapsed or secondary patients (χ(2)=11.302, P=0.010) . Moreover, the proportion of patients with clonal heterogeneity gradually increased according to their prognostic risk (χ(2)=17.505, P=0.022) . Based on the clone analysis, the proportion of primary clones of patients with RUNX1 mutation was higher (χ(2)=4.527, P=0.033) . The analysis of clonal heterogeneity and efficacy demonstrated that patients with three or more clones had significantly lower overall survival (OS) and progression-free survival (PFS) compared to other patients (OS, χ(2)=13.533; P=0.004; PFS, χ(2)=9.817; P=0.020) , while in the intermediate-risk group, patients with a significant clonal heterogeneity also exhibited a significant decrease in PFS (χ(2)=10.883, P=0.012) . Cox regression multivariate analysis revealed that carrying three or more clones was an independent factor affecting prognosis, and OS and PFS were significantly lower than those of patients without clones (OS, HR=3.296; 95% CI, 1.568-6.932; P=0.002; PFS, HR=3.241; 95% CI, 1.411-7.440; P=0.006) . Conclusion: Clonal heterogeneity may reflect the biological characteristics of a tumor, suggesting its drug resistance, refractory, and invasiveness, and further evaluate the treatment effect and prognosis of patients.

[Clinical analysis of gene mutation characteristics and mutation burden in myelodysplastic syndrome].

Objective: To investigate the relationship between gene mutation characteristics, mutation burden and general condition, disease subtype and karyotype of patients with myelodysplastic syndrome (MDS), and its clinical value. Methods: High-throughput sequencing was used to detect 65 blood tumor-related genes in 191 MDS patients and 9 secondary acute myelocytic leukemia patitents(SAML), and to analyze the characteristics of abnormal genes, mutation burden, as well as the relationship with disease subtypes, chromosome karyotypes and age. Results: Mutations were found in 148 patients (77.5%), including 47 abnormal genes and 186 mutation sites. And gene mutations were found in 9 SAML patients, the number of mutations was significantly higher than that in MDS patients (χ(2)=11.911, P=0.018). Among the abnormal genes, the mutation frequency of U2AF1 (37.3%) and ASXL1 (41.6%) were higher, and there were significant differences in mutation burden among different abnormal genes (F=91.946, P<0.001). There were differences in the number of gene mutations among different subtypes of MDS, and the number of EB-2 gene mutations was the highest (2.2±1.5). In SLD, MLD, EB-1 and EB-2, the proportion of carrying ≥ 3 mutations increased gradually (χ(2)=52.471, P=0.037). TP53 mutation was associated with abnormal karyotype (r(φ)=0.177, P=0.019), especially with complex karyotype (r(φ)=0.440, P<0.001), while NPM1 mutation is associated with normal karyotype (r(φ)=0.173, P=0.024). The number of mutations carried by patients under 30 years old was the least, and the number of mutations increased with the increase of age. The number of mutations was the most in patients aged 60 to 79 years old (P=0.017), and the mutation frequency of epigenetic related genes increased with the increase of age (P=0.041). Conclusions: The mutation characteristics and mutation load of MDS-related genes are closely related to clinical factors such as disease subtype, chromosome karyotype and patient age.

[Clonal heterogeneity and its prognostic significance in acute lymphoblastic leukemia].

Objective: To explore the characteristics and clinical significance of clonal heterogeneity in patients with acute lymphoblastic leukemia(ALL). Methods: From January 2016 to June 2019, 170 newly diagnosed ALL patients were enrolled in the Department of Hematology, Henan Cancer Hospital, including 93 males and 77 females, with a median age of 17 (2-80) years. Fifty-two ALL-related genes were detected by high-throughput sequencing technique. The clonal heterogeneity of mutations was analyzed according to the variant allele frequency (VAF) and the results of flow cytometry. The prognostic value of mutations was also evaluated. Results: Gene mutations were detected in 121 (71.2%, 121/170) patients, of which 2 or more clones were detected in 18 (52.9%, 18/34) T-cell acute lymphoblastic leukemia patients, while only 23 (16.9%, 23/136) B-cell acute lymphoblastic leukemia patients were positive of multiple mutations (P<0.01).Gene mutation-related clonal heterogeneity analysis showed that 2 or more clones were frequent in patients with NOTCH1 mutations (13/19 patients) (P<0.01). Event free survival (EFS) in patients with 3 or more clones was significantly lower than other patients (χ(2)=10.330, P=0.016). Child ALL patients had similar result, that multiple clones predicted lower overall survival (OS) and EFS (OS: χ(2)=7.974, P=0.047; EFS: χ(2)=10.860, P=0.013). Conclusion: Clonal heterogeneity in ALL patients is closely related to the different origin of lymphocyte lineages and the age of onset, which may reveal the nature of the disease and predict the clinical outcome.

[The genetic characteristics of BCR-ABL-negative myeloproliferative neoplasms].

Objective: To explore the relationship between driver gene mutation (JAK2, MPL and CALR) and disease type in BCR-ABL negative myeloproliferative neoplasms (MPNs) including primary myeloid fibrosis (PMF), essential thrombocytosis (ET) and polycythemia vera (PV). Methods: A total of 32 MPN related genes were detected by high-throughput sequencing in 156 MPN patients. The relationships between disease type and patients' general performance, the characteristics of driver gene mutations, concomitant gene mutations were analyzed. Results: In the population with JAK2 V617F positive mutation, the proportion of patients over 60 years old in PMF was higher than that with ET or PV. By high-throughput sequencing, 22 concomitant gene mutations were detected in 46 patients with JAK2, MPL or CALR mutations, including 4 (8.3%) in PV, 20 (29.4%) in ET, and 22 (55.0%) in PMF. DNMT3A mutation was detected only in patients with PV, while splicing factor related genes including SF3B1, SRSF2 and U2AF1 were only accompanied by PMF. According to the variation allele frequency (VAF) value of JAK2 V617F mutation, the VAF value associated with PV was the highest (68.15%), followed by PMF (37.7%) and ET (23%). However, there were significant differences in the incidence of JAK2 V617F homozygous among 3 different diseases. In patients with JAK2 mutation, the proportion of other gene mutations in PV and ET was significantly lower than that in PMF. Conclusions: Under the condition of common driver gene mutations (JAK2, MPL and CALR), patients' age, VAF value and homozygous state, concomitant gene mutations are closely related to different disease type. These correlations help to improve clinical understanding of disease characteristics and risk assessment.

[Application of multiple nucleotide polymorphism analysis in chimerism detection after allogeneic hematopoietic stem cell transplantation].

Objective: To establish a new method for chimerism analysis after allogeneic hematopoietic stem cell transplantation by using multiple nucleotide polymorphism sequencing (MNPseq) , and to explore its feasibility and superiority. Methods: One hundred MNP fragments were screened and chimeric analysis was performed by high-throughput sequencing technology. The accuracy and sensitivity of the method were verified by simulating chimeric samples and post-transplant samples and comparing them with short tandem repeat (STR) analysis, fusion gene quantitative detection and flow cytometry for minimal residual disease. Results: The accuracy and sensitivity of MNPseq were better than those of STR, in which the sensitivity could reach 0.01%, about 100 times more sensitive than STR. MNPseq could further distinguish 42 STR fully chimeric samples, and after corrected by cutoff value, it was correlated with the quantitative detection of fusion gene. MNPseq could correct false positive of STR caused by the shadow peak, and could be used to detect chimeric samples lacking pre-transplant information from donors and recipients. Conclusion: MNPseq analysis based on high-throughput sequencing is a more accurate and sensitive chimerism detection method, and it solves the problem that chimerism cannot be detected due to the lack of pre-transplant information, which has extremely high clinical application value.

[The expression of CRLF2 in adult Ph negative acute B lymphocytic leukemia and its prognostic significance].

Objective: To detect the expression of CRLF2 in adult Ph negative acute B lymphocytic leukemia (B-ALL) in newly diagnosed cases, and to investigate the relationship between CRLF2 and the general clinical characteristics, efficacy and prognosis. Methods: 103 cases of newly diagnosed adult B-ALL patients were investigated from Apr 2016 to Dec 2017 in the Department of Hematology, Henan Cancer Hospital. Bone marrow samples was used to detect the expression of CRLF2 in leukemic cells. The expression of CRLF2 ≥20% was defined as CRLF2-high group and <20% was defined as CRLF2-low group. The clinical characteristics and prognosis of the two groups were compared. Results: The Median overall survival (OS) and disease free survial (DFS) in CRLF2-high group were 9.0 months and 4.25 months, respectively. CRLF2-low group were 15.5 months and 10.25 months, respectively. There was a statistically significant difference in median OS and DFS between the two groups (P=0.007, P=0.000) . The 18-month OS and DFS in CRLF2-high group were 38.6% and 25.1%, respectively. CRLF2-low group were 57.8% and 42.3%, respectively. Multivariate analysis showed high expression of CRLF2 was an independent risk factor for OS (HR=2.991, 95% CI 1.429-6.261, P=0.004) and DFS (HR=2.374, 95%CI 1.146-4.960, P=0.041) in patients. Conclusion: Patients with high expression of CRLF2 had poor prognosis.