Identification of COQ2 as a regulator of proliferation and lipid peroxidation through genome-scale CRISPR-Cas9 screening in myeloma cells.

Multiple myeloma (MM) is the second most common malignant haematological disease with a poor prognosis. The limit therapeutic progress has been made in MM patients with cancer relapse, necessitating deeper research into the molecular mechanisms underlying its occurrence and development. A genome-wide CRISPR-Cas9 loss-of-function screening was utilized to identify potential therapeutic targets in our research. We revealed that COQ2 plays a crucial role in regulating MM cell proliferation and lipid peroxidation (LPO). Knockout of COQ2 inhibited cell proliferation, induced cell cycle arrest and reduced tumour growth in vivo. Mechanistically, COQ2 promoted the activation of the MEK/ERK cascade, which in turn stabilized and activated MYC protein. Moreover, we found that COQ2-deficient MM cells increased sensitivity to the LPO activator, RSL3. Using an inhibitor targeting COQ2 by 4-CBA enhanced the sensitivity to RSL3 in primary CD138+ myeloma cells and in a xenograft mouse model. Nevertheless, co-treatment of 4-CBA and RSL3 induced cell death in bortezomib-resistant MM cells. Together, our findings suggest that COQ2 promotes cell proliferation and tumour growth through the activation of the MEK/ERK/MYC axis and targeting COQ2 could enhance the sensitivity to ferroptosis in MM cells, which may be a promising therapeutic strategy for the treatment of MM patients.

Alternative splicing analysis showed the splicing factor polypyrimidine tract-binding protein 1 as a potential target in acute myeloid leukemia therapy.

Alternative splicing (AS) is a universal post-transcriptional regulation process in cells, and increasing evidences have validated its crucial role in tumors. We collected AS event, gene expression, and clinical data of 178 AML patients from The Cancer Genome Atlas (TCGA) project. More than 1,000 AS events were found associated with overall survival (OS), and alternate promoter (AP) events were the most significant. The expression of the KIAA0930 transcript was the most significantly different AS event selected from AP events and significantly correlated with the expression of the splicing factor (SF) polypyrimidine tract-binding protein 1 (PTBP1). Then, the roles of PTBP1 on AS of the KIAA0930 and the proliferation of AML cells were confirmed. KIAA0930 variant 1 (KIAA0930-1) was upregulated and variant 2 (KIAA0930-2) downregulated with knockdown PTBP1 expression of AML cells by specific shRNA. A low level of PTBP1 can decrease the proliferation ability of AML cells. In conclusion, the results showed that PTBP1 might be a potential target for AML therapy.

Association of plasma intermedin levels with progression and metastasis in men after radical prostatectomy for localized prostatic cancer.

BACKGROUND: Adrenomedullin levels in the peripheral blood are associated with prognosis of some cancers. Intermedin is structural similarities to adrenomedullin. OBJECTIVE: The current study aimed to investigate the prognostic value of plasma intermedin levels for progression and distant metastasis in prostate cancers. METHODS: This study included 218 patients undergoing radical prostatectomy for localized prostatic cancer and 218 age-matched healthy men. Plasma intermedin levels were measured using radioimmunoassay. The relationships between plasma intermedin levels and 5-year progression and 5-year distant metastasis were evaluated using a multivariate analysis. RESULTS: Plasma intermedin levels were markedly higher in all patients than in healthy men. Patients with Gleason score ≥ 7, tumor node metastasis stage T2, organ unconfined, present extra-prostatic extension, seminal vesicle invasion or positive lymph node had higher intermedin levels. Intermedin was identified as a prognostic predictor for 5-year progression and 5-year metastasis. Under receiver operating characteristic curves, intermedin had high predictive values for 5-year progression and 5-year metastasis. CONCLUSIONS: Elevated plasma intermedin levels are independently associated with long-term recurrence and distant metastasis of prostate cancer and intermedin has potential to be a prognostic predictive biomarker for prostate cancer.

[Determination of plasma protein binding rate of methyl protodioscin with ultrafiltration].

OBJECTIVE: To study the plasma protein binding rate of methyl protodioscin. METHOD: The ultrafiltration was employed to determine the plasma protein binding rate of methyl protodioscin. The plasma concentrations of methyl protodioscin were measured by HPLC-MS-MS. RESULT: The plasma protein binding rate of methyl protodioscin with rat plasma at the concentration of 20.0, 100 and 200 microg x mL(-1) were (94.6 +/- 0.16)%, (91.6 +/- 0.35)% and (86.10 +/- 0.60)%, respectively, while the plasma protein binding rate of methyl protodioscin with normal human plasma at the above concentrations were (82.11 +/- 5.12)%, (84.54 +/- 0.32)% and (88.52 +/- 1.02)%, respectively. CONCLUSION: The binding rate of methyl protodioscin with plasma protein is high.