Telomerase reverse transcriptase gene polymorphisms and cervical cancer susceptibility in high-risk human papillomavirus-infected women.

OBJECTIVE: To investigate the relationship between Human telomerase reverse transcriptase (hTERT) gene polymorphisms and the susceptibility and clinicopathological parameters of cervical cancer in women infected with high-risk human papillomavirus (HR-HPV). METHOD: A total of 380 patients with HPV-infected cervical cancer who were admitted to the Jilin province Maternal and Child Health Care Hospital (Jilin province Obstetrics Quality Control Center) from July 2019 to July 2023 were selected as case group, and 408 women with negative HPV results in the cervical cancer screening results of the physical examination in the same hospital were selected as the control group. Restriction fragment length polymorphisms polymerase chain reaction was used to detect the polymorphisms of hTERT, and its relationship with the susceptibility to high-risk HPV infection and clinicopathological parameters in patients with cervical cancer was analysed. RESULTS: Individuals carrying the GA and AA genotypes of rs2736122 were significantly associated with an increased risk of cervical cancer when compared with the GG genotype and the adjusted ORs were 0.53 (0.37-0.79) for the AA genotype and 0.73 (0.59-0.88) for the A allele genotype. Besides, GG genotype or G allele of rs2853677 presented a significant influence on cervical cancer, with ORs of 0.59 (0.41-0.86) and 10.77 (0.63-0.94), respectively, when compared with the AA genotype. And rs2853677 have statistically significant difference in tumour diameter and degree of differentiation subgroup(p < 0.05). CONCLUSION: The results of this study indicate that the hTERT gene rs2736122AA and rs2853677 GG genotypes can increase the susceptibility of high-risk HPV infection in cervical cancer patients. And rs2853677 is related to tumours above 4 cm and highly differentiated tumours. But both have nothing to do with the patient's chemotherapy sensitivity.

[Study of apoptosis gene expression in U937 cells induced by adhesion culture with mesenchymal stem cell].

OBJECTIVE: To compare apoptosis gene expression profiling of U937 cells in suspension culture with that cultivated with mesenchymal stem cells (MSCs), and find out the relationship between drug resistance of leukemia cells and hemopoietic microenvironment. METHODS: U937 cells were cultivated in adhesion culture with MSCs and in suspension culture for 48 hours. Cell cycle was determined by flow cytometry and gene expression profiling by cDNA microarray. RESULTS: Compared with that in suspension, G(0)/G(1) fraction of U937 cells increased in adhesion culture (45.3 +/- 3.1)% vs (32.6 +/- 2.1)%, respectively (P < 0.05), whereas G(2)/M fraction and apoptosis rate were decreased. After 48 h twenty-eight differential expression genes were screened out in 487 apoptosis-related genes, among which 27 were up-regulated and were mainly apoptosis-suppressor genes, apoptosis-promoter genes, cell cycle positive control genes and cell cycle negative control genes. But Bcl-XL was up-regulated most obviously. The only one gene down-regulated was an apoptosis promoter gene. CONCLUSION: Adhesion culture with MSCs can lead to growth suppression and decrease natural apoptosis of U937 cells. The mechanism was multiple gene effects, but Bcl-XL may be of the most importance.

Study on the bone marrow mesenchymal stem cells induced drug resistance in the U937 cells and its mechanism.

BACKGROUND: The hematopoietic microenvironment (HM) plays a critical role in malignant cell growth, patient survival, and response to chemotherapy in hematologic malignancies. However, mechanisms associated with this environmental influence remain unclear. In this study, we investigated the role of bone marrow derived mesenchymal stem cells (MSCs) in U937 cell line, to find out the relations between leukemia drug resistance and the MSCs. METHODS: U937 cells were cultured in suspension or grew adherently with MSCs. The cell growth curve was drawn and the cell cycle was measured by flow cytometry. Apoptosis and sensitivity of U937 to daunoblastina (DNR) were quantified by DNA ladder detection and trypan blue exclusion assays, respectively. The gene expression profile chip technology was used to determine and analyze the changes in apoptosis-related gene expression after adherent culture and the expression of MDR1 mRNA was assessed by reverse transcriptional polymerase chain reaction (RT-PCR) at the same time. RESULTS: In the adherent culture, the proliferation of the U937 cells was inhibited, the G0/G1 phase cells increased (F = 64.9726, P < 0.0001), G2/M phase cells were decreased (F = 98.1361, P < 0.0001) and the natural apoptosis rate was decreased (F = 24.0866, P < 0.0001) compared with those in the suspended culture. U937 cell viability was enhanced and cell apoptosis was blocked during DNR treatment in adherent culture with MSCs. Thirty-nine differently expressed genes were screened from the 487 apoptosis related genes in the adherent culture U937 cells. Among the 37 upregulated genes, Bcl-XL was upregulated most significantly. Two genes were downregulated. Adherent culture did not induce MDR1 mRNA expression in U937 cells. CONCLUSIONS: MSCs play a role in modulating the proliferation of U937 cells and response of U937 cells to DNR, and Bcl-XL apoptosis-inhibiting gene may be most important in determining the sensitivity of leukemic cells to treatment, which is not related to MDR1.