Cell Cycle-Related Clinical Applications

Effect of the LIF gene on the cell cycle and apoptosis of ovarian granulosa cells in white Muscovy ducks

Leukaemia inhibitory factor (LIF), a member of the interleukin-6 (IL-6) family, is a multifunctional cytokine. The maturation-to-ovulation process of poultry follicles is determined by granulosa cell proliferation and differentiation. Granulosa cell apoptosis and degeneration lead to follicular atresia, which reduces the number of normally developing follicles and leads to a decrease in the poultry egg production rate, thus affecting the large-scale development of poultry breeding. In this study, the LIF gene overexpression vector pCDH-CMV-LIF and a siRNA that inhibits LIF gene expression were transfected into primary granulosa cells from white Muscovy duck ovaries for functional study. Compared with that in the control group, LIF gene expression was confirmed to be significantly decreased or increased in the transfection groups (P < 0.01). After LIF overexpression, the expression of the cell cycle-related genes CCND1, CDK-1 and PCNA was decreased (P < 0.05); apoptosis was promoted; the proapoptotic genes Bax and caspase-3 were significantly upregulated (P < 0.01); and the antiapoptotic gene Bcl-2 was significantly downregulated (P < 0.01). After LIF interference, the expression of the cell cycle-related genes CCND1, CCNE1, CDK-1 and PCNA and the antiapoptotic gene Bcl-2 significantly increased (P < 0.01), whereas the expression of the proapoptotic genes Bax, caspase-3 and caspase-9 significantly decreased (P < 0.01). In summary, the LIF gene is involved in regulating the biological function of ovarian granulosa cells in white Muscovy ducks. LIF gene expression promotes granulosa cell apoptosis and inhibits cell cycle progression. These experimental results provide insights into the follicular development mechanism of white Muscovy ducks.

Cell cycle checkpoint revolution: targeted therapies in the fight against malignant tumors

Malignant tumors are among the most important causes of death worldwide. The pathogenesis of a malignant tumor is complex and has not been fully elucidated. Studies have shown that such pathogenesis is related to abnormal cell cycle progression. The expression levels of cyclins, cyclin-dependent kinases (CDKs), and CDK inhibitors as well as functions of the cell cycle checkpoints determine whether the cell cycle progression is smooth. Cell-cycle-targeting drugs have the advantages of high specificity, low toxicity, low side effects, and low drug resistance. Identifying drugs that target the cell cycle and applying them in clinical treatments are expected to promote chemotherapeutic developments against malignant tumors. This article aims to review drugs targeted against the cell cycle and their action mechanisms.

Distinct Molecular Processes Mediate Donor-derived Cell-free DNA Release From Kidney Transplants in Different Disease States

BACKGROUND

Among all biopsies in the Trifecta-Kidney Study ( ClinicalTrials.gov NCT04239703), elevated plasma donor-derived cell-free DNA (dd-cfDNA) correlated most strongly with molecular antibody-mediated rejection (AMR) but was also elevated in other states: T cell-mediated rejection (TCMR), acute kidney injury (AKI), and some apparently normal biopsies. The present study aimed to define the molecular correlates of plasma dd-cfDNA within specific states.

METHODS

Dd-cfDNA was measured by the Prospera test. Molecular rejection and injury states were defined using the Molecular Microscope system. We studied the correlation between dd-cfDNA and the expression of genes, transcript sets, and classifier scores within specific disease states, and compared AMR, TCMR, and AKI to biopsies classified as normal and no injury (NRNI).

RESULTS

In all 604 biopsies, dd-cfDNA was elevated in AMR, TCMR, and AKI. Within AMR biopsies, dd-cfDNA correlated with AMR activity and stage. Within AKI, the correlations reflected acute parenchymal injury, including cell cycling. Within biopsies classified as MMDx Normal and archetypal No injury (NRNI), dd-cfDNA still correlated significantly with rejection- and injury-related genes. TCMR activity (eg, the TCMR Prob classifier) correlated with dd-cfDNA, but within TCMR biopsies, top gene correlations were complex and not the top TCMR-selective genes.

CONCLUSIONS

In kidney transplants, elevated plasma dd-cfDNA is associated with 3 distinct molecular states in the donor tissue: AMR, recent parenchymal injury (including cell cycling), and TCMR, potentially complicated by parenchymal disruption. Moreover, subtle rejection- and injury-related changes in the donor tissue can contribute to dd-cfDNA elevations in transplants considered to have no rejection or injury.