Platelet RNA enables accurate detection of ovarian cancer: an intercontinental, biomarker identification study

Platelets are reprogrammed by cancer via a process called education, which favors cancer development. The transcriptional profile of tumor-educated platelets (TEPs) is skewed and therefore practicable for cancer detection. This intercontinental, hospital-based, diagnostic study included 761 treatment-naïve inpatients with histologically confirmed adnexal masses and 167 healthy controls from nine medical centers (China, n = 3; Netherlands, n = 5; Poland, n = 1) between September 2016 and May 2019. The main outcomes were the performance of TEPs and their combination with CA125 in two Chinese (VC1 and VC2) and the European (VC3) validation cohorts collectively and independently. Exploratory outcome was the value of TEPs in public pan-cancer platelet transcriptome datasets. The AUCs for TEPs in the combined validation cohort, VC1, VC2, and VC3 were 0.918 (95% CI 0.889-0.948), 0.923 (0.855-0.990), 0.918 (0.872-0.963), and 0.887 (0.813-0.960), respectively. Combination of TEPs and CA125 demonstrated an AUC of 0.922 (0.889-0.955) in the combined validation cohort; 0.955 (0.912-0.997) in VC1; 0.939 (0.901-0.977) in VC2; 0.917 (0.824-1.000) in VC3. For subgroup analysis, TEPs exhibited an AUC of 0.858, 0.859, and 0.920 to detect early-stage, borderline, non-epithelial diseases and 0.899 to discriminate ovarian cancer from endometriosis. TEPs had robustness, compatibility, and universality for preoperative diagnosis of ovarian cancer since it withstood validations in populations of different ethnicities, heterogeneous histological subtypes, and early-stage ovarian cancer. However, these observations warrant prospective validations in a larger population before clinical utilities.

Effect of BRCA2 mutation on familial breast cancer survival: A systematic review and meta-analysis / 华中科技大学学报（医学）（英德文版）

Reports of BRCA2 genetic mutations on the prognosis of familial breast cancer (BC) patients have been contradictory. True difference in survival, if it exists, would have important implications for genetic counseling and in treatment of hereditary BC. The purpose of this study was to compare overall survival rate (OSR) among BRCA2 mutation carriers, non-carriers and sporadic BC patients. We searched the PUBMED and EMBASE databases and retrieved 4529 articles using keywords that included breast cancer, BRCA, prognosis and survival. Nine articles were selected for systematic review and among them 6 were included in our meta-analysis. We used the fixed and random effect models to calculate the summary odds ratio (OR) and corresponding 95% confidence interval (CI). BRCA2 mutation carriers had significantly higher long-term OSR than non-carriers (OR=0.69 [95% CI=0.5-0.95]), while both short-term and long-term OSR of BRCA2 mutation carriers did not differ from those of patients with sporadic disease (OR=1.11 [95% CI=0.74-1.65]; 0.85 [95% CI=0.38-1.94], respectively). For BC-specific survival rate (BCSSR), BRCA2 mutation carriers had a similar BCSSR to the non-carriers (OR=0.61 [95% CI=0.28-1.34]). There was no significant difference in disease-free survival (DFS) between BRCA2 mutation carriers and patients with sporadic disease. Our results suggest that BRCA2 mutation increases long-term OSR in hereditary BC, which reminds us a new prospect of management of the disease.

Silencing of cell cycle checkpoint kinase gene enhances cisplatin-induced apoptosis of lung cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the changes in cell cycle induced by cisplatin (DDP) and the effect of antisense oligonucleotide (AsODN) targeting Chk1/2 on DDP-induced apoptosis in lung cancer cell line A549 cells.</p><p><b>METHODS</b>The characteristics of cell cycle and apoptosis induced by DDP were detected by flow cytometry using SubG1 method. Chk1/2 mRNA and protein expression were assayed by RT-PCR and Western blot under best condition of transfection of AsODN targeting Chk1/2 by lipofection. Apoptosis of A549 cells induced by DDP was determined by flow cytometry using AnnexinV-FITC staining after transfection of Chk1/2 AsODN.</p><p><b>RESULTS</b>Asynchronized A549 cells were treated with 10 micromol/L DDP, and significant S-phase arrest was observed at 12 h later. Transfection with antisense oligonucleotide targeting Chk1/2 inhibited the Chk1/2 expression at both mRNA and protein levels. Either Chk1 or Chk2-specific AsODN consistently enhanced DNA damage-induced apoptosis by 100% - 200%, compared with that in the sODN control (P < 0.05), but combined use of Chk1- and Chk2-specific AsODN did not show synergistic effects as compared with that induced by treatment with Chk1- or Chk2-specific AsODN alone (P > 0.05).</p><p><b>CONCLUSION</b>Chk1 and Chk2 may be regarded as effective targets of chemotherapy for lung cancer. Silencing the key effector Chk1 and Chk2 genes may significantly increase the chemosensitivity of lung cancer cells.</p>

Down-regulation of Chk1/Chk2 gene expression increases apoptosis in irradiated HeLa cells and its mechanism / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To explore the increasing effect of blocking Chk1 and /or Chk2 gene by Chk1 or Chk2-specific antisense oligodeoxynucleotides (AsODN) on apoptosis in HeLa cell line after irradiation and its mechanism of action.</p><p><b>METHODS</b>Asynchronized HeLa cells were exposed to (60)Co-irradiation at different dosage to activate G(2)/M checkpoint arrest. The cell cycle profiles were observed in HeLa cells after irradiation at a range of various doses and different time points by flow cytometry. In the experimental groups, Chk1/2 sODN and AsODN alone or in combination were transfected into HeLa cells, and the cells were exposed to (60)Co-irradiation at 24 h after transfection. The changes of Chk1/2 protein expression were assayed by Western blot and confocal laser scanning microscopy (Confocal), and the cell cycles, apoptosis rates and cell cycle specific apoptosis were detected by annexin V-PI labeling and flow cytometry.</p><p><b>RESULTS</b>Apoptotic response was significantly increased in the Hela cells after G(2)/M arrest and was inversed to activation of G(2)/M checkpoint. Either Chk1 or Chk2-specific AsODN consistently enhanced DNA damage-induced apoptosis by 90% approximately 120%, compared to corresponding sODN control (P < 0.05). Unexpectedly, combined use of Chk1- and Chk2-specific AsODN did not produce synergistic effect as compared to treatment with Chk1- or Chk2-specific AsODN alone (P > 0.05). While irradiated HeLa cells underwent apoptosis preferentially in G(1)-phase, apoptosis occurred in either of G(1)-, S- or G(2)/M -phase in the presence of Chk1 and/or Chk2 AsODN.</p><p><b>CONCLUSION</b>The radioresistance is mainly induced by activating the cell cycle checkpoint signal transduction pathway after irradiation, and abrogating of the key effector Chk1 and Chk2 may increase the apoptotic sensitivity to irradiation due to changes of the pattern of cell cycle specific apoptosis.</p>

ATM expression in K562 and SiHA cell lines in relation to their cell cycle restardation after gamma-irradiation / 中国实验血液学杂志

Ataxia telangiectasis is caused by the mutation of AT gene (ATM) and it is characterized by hypersensitivity to the radiation. In order to investigate the relationship between ATM mRNA expression of K562 and SiHA two kinds of tumor cell lines and their cell cycle restardation after gamma-irradiation, their ATM mRNA expressions were measured by semi-quantitive RT-PCR and the cells were irradiated at the dose of 6, 10 and 15 Gy of (60)Co gamma ray and the change of the apoptosis and cell cycle arrest phenomenon were observed at the time of 6, 12, 24, 48 and 60 hours after irradiation. The results showed that the ATM mRNA relative expression level of K562 cell line was 0.04, that of SiHA cell line was 0.80, the ATM transcript levels in SiHA cells were 20 times as much as that in K562. In conclusion, the G(2)/M phase restardation after irradiation was observed in both cell lines, whereas SiHA exhibited a much stronger cell cycle restardation, a self-protection function, than that of K562.

Correlation of expression of RhoA (RhoC and their effector ROCK-1 with malignant phenotype of ovarian cancer cells in vitro / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the expression of RhoA, RhoC and their effector ROCK-1 in four ovarian cancer cell lines in vitro and their correlation with invasiveness.</p><p><b>METHODS</b>Expression of RhoA, RhoC and ROCK-1 mRNA and protein in four ovarian cancer cell lines SW626, Skov-3, A2780 and Caov-3 was detected by RT-PCR and Western blot assay. Invasion assay was done in Boyden chamber.</p><p><b>RESULTS</b>The expression levels of RhoA, RhoC and ROCK-1 mRNA and protein varied in the four different cell lines examined. The expression level of RhoC, but not RhoA and ROCK-1, was significantly correlated with the invasive capability of these cells in vitro (r = 0.95, P < 0.01). Expression of RhoA at the level of transcription was not correlated with that at the translation level. The expression of RhoA and RhoC did not correlate with that of ROCK-1.</p><p><b>CONCLUSION</b>Expression level of RhoC may serve as an independent parameter in evaluating metastasis and become a new target in inhibiting ovarian cancer metastasis.</p>

Mdr-1 ribozyme in the reversal of multidrug resistance in human ovarian cancer / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To study the mechanism of multidrug resistance and its reversal by mdr-1 ribozyme in human ovarian cancer.</p><p><b>METHODS</b>The expression of mdr-1 and p-glycoprotein (p-gp) was studied by confocal laser microscope (Confocal), RT-PCR and Western blot analysis in adriamycin-resistant human ovarian cancer cell line (A2780/ADM) and adriamycin-sensitive one (A2780). The mdr-1 ribozyme was transfected into the A2780/ADM by Lipofectamine 2000 to overcome the multidrug resistance in ovarian cancer.</p><p><b>RESULTS</b>The expression of mdr-1 mRNA and p-gp in A2780/ADM was significantly higher than that in A2780. The expression of mdr-1 mRNA and p-gp in A2780/ADM was lowered after being transfected by mdr-1 ribozyme.</p><p><b>CONCLUSION</b>Multidrug resistance of A2780/ADM, possibly being caused by overexpression of mdr-1 gene, can be partially reversed by mdr-1 ribozyme.</p>

Transfection of chk1/2 antisense oligonucleotide to HL-60 cell line increases the apoptotic sensitivity to irradiation / 中华血液学杂志

<p><b>OBJECTIVE</b>To block signal transduction of cell cycle checkpoints by antisense blocking of chk1/2 gene to increase the radiation sensitivity of HL-60 cell line.</p><p><b>METHOD</b>To transfect the HL-60 cell with chk1/2 antisense and sense chain alone and in combination, expose the cells to irradiation at 24 h after the transfection, the chk1 protein change was assayed by Western blot and the cell cycles and annexin V apoptosis rates by FCM.</p><p><b>RESULTS</b>The irradiated apoptosis sensitivity was increased by antisense blocking of chk1 gene in HL-60 cell line, the apoptotic rate was 26.31% being significantly higher than that of the sense blocking (10.34%) (P < 0.05), Furthermore, the G(2)/M phase blocking phenomenon decreased and a synergic effect was observed in antisense blocking both the chk1 and chk2 genes.</p><p><b>CONCLUSION</b>Antisense blocking of chk1/chk2 could increase the apoptotic sensitivity to irradiation.</p>