Molecular testing on serous effusion: An update

Cytological examination of the effusion fluid provides valuable information regarding the presence of malignancy. At times, it is challenging to diagnose malignant cells in serous effusion. The various ancillary techniques are available to solve the problem including immunocytochemistry, DNA ploidy, and multicolored flow cytometry. At present, the molecular tests on the effusion sample are of growing interest. The effusion sample is rich in cells and cell-free fluid that contains free DNA, cytokines, and extracellular vesicles. Molecular tests in effusion sample not only provide a diagnosis of malignancy but can also give valuable information that may be essential for the individualized therapy, management, and prognostic assessment. In this paper, we reviewed the application of the different molecular tests in the effusion sample.

Deciphering heterogeneity of circulating epithelial cells in breast cancer patients

Circulating tumor cells (CTCs) and tumor hybrid cells, being the leading players in metastasis, have prognostic relevance and are potential antimetastatic targets. CTCs are identified as epithelial-positive and CD45 (leukocyte)-negative cells, whereas tumor hybrid cells usually have epithelial and leukocyte components. However, epithelial and hybrid cells are also observed in healthy subjects that complicate the detection of CTCs and tumor hybrid cells in cancer patients. This study evaluated the diversity of CD45-negative and CD45-positive circulating epithelial cells (CECs) in breast cancer patients (n=20) using single-cell RNA sequencing. We also tried to detect CTCs and tumor hybrid cells among CD45─ CECs and CD45+ CECs by analyzing DNA ploidy since aneuploidy is a hallmark of cancer cells. Aneuploid cells were predominantly detected in CD45─ CECs, whereas CD45+ CECs were mainly diploid. Most transcriptional cancer features, including many cancer-associated signaling pathways, were specific to aneuploid cells of one CD45─ CEC cluster. These cells were also enriched by platelet genes and signaling pathways that may indicate their increased potential to adhere with thrombocytes. In CD45+ CECs, only one cluster had many aneuploid cells that were surprisingly negative for transcriptional cancer features. Thus, CD45─ and CD45+ CECs are highly heterogeneous in breast cancer patients and consist of transcriptionally-distinct cell populations with varying degrees of DNA ploidy where aneuploid cells are likely CTCs and tumor hybrid cells.

Generating Large Numbers of Human Megakaryocytes from Pluripotent Stem Cells

The process of hemostasis and blood coagulation relies heavily on a sufficient supply of platelets (PLTs, also known as thrombocytes) within a person's bloodstream. Platelet transfusion is an effective treatment for thrombocytopenia-related diseases, yet paucity of supply and limited shelf-life (5 - 7 days) remain challenging. PLTs are generated by the proliferation and differentiation of hematopoietic stem and progenitor cells (HSPCs) into megakaryocytes (MKs), a rare subset of large polyploid bone marrow cells. Methods to produce MKs in vitro by inducing mesodermal specification and hematopoietic differentiation of human pluripotent stem cells (hPSCs) could provide a reliable and safe supply of PLTs for transfusion and would also be amenable to gene editing for generation of HLA-null universal PLTs. Culture methods to generate hPSC-derived MKs and PLTs have been described, yet published protocols lack standardization, are PSC line dependent and/or promote differentiation of other lineages, resulting in low MK cell yields and purity. The use of feeder cells and/or viral vectors also limits the clinical and scale-up applicability. Here, we describe an efficient feeder cell-free and serum-free culture system that promotes the selective differentiation of hPSCs from multiple ES and iPS lines into polyploid MKs with high purity and yields and ability to generate platelets. The 17-day protocol includes two stages: a 12-day stage to differentiate hPSCs into megakaryocytic-biased HSPCs through endothelial-to-hematopoietic transition (H-phase), and a 5-day stage to further differentiate HSPCs into mature MKs (MK-phase). at the start of the H-phase, hPSC aggregates were plated in mTeSR TM media on Matrigel ®-coated plates at 16 aggregates (100 - 200 µm in diameter, ~100 cells per aggregate) per cm 2 to allow attachment overnight (Day -1). The cells were then cultured in mesoderm-induction medium for 3 days (Day 0 - 3), and subsequently in hematopoietic specification medium for 9 days (Day 3 - 12). During this phase, PSC-derived HSPCs emerged from an adherent layer of endothelial cells and were released into suspension. On day 12 these nonadherent cells were harvested and seeded at 1 - 3.5 × 10 5 cells/mL in MK maturation medium containing thrombopoietin (TPO) and other hematopoietic growth factors and cultured for 5 additional days (MK-phase, Day 12 - 17). At the end of H-phase (day 12) and MK-phase (day 17) the cells were counted and assessed for HSPC markers (CD34/CD45), the erythroid marker glycophorin A (GlyA), MK markers (CD41a/CD42b), DNA ploidy profile and PLT production by flow cytometry and immunofluorescence microscopy. Two embryonic stem (ES) cell lines (H1 and H9), and two induced pluripotent stem (iPS) cell lines (WLS-1C and STiPS-R038) were used in this study. At the end of H-phase (Day 12), on average 48% (range: 34 - 72%) of cells released into suspension co-expressed CD41a and CD42b markers, with an average yield of 93 CD41a +CD42b + cells per seeded hPSC (range: 30 - 200, n = 4 for H9/1C, n = 3 for H1/R038). The cells also expressed CD34 (average of 78% CD34 + cells) and GlyA (average of 71% GlyA + cells), indicating that the H-phase may support differentiation of PSCs to megakaryocyte-erythroid progenitors. At the end of MK-phase (Day 17), on average 82% of the cells expressed CD41a (range: 70 - 99%), 62% of the cells co-expressed CD41a and CD42b (range: 40 - 85%), and an average of 253 CD41a +CD42b + cells were generated per seeded hPSC (range: 70 - 700 MKs, n = 11 for H1/H9/R038, n = 7 for 1C). Of note, less than 5% of cells expressed GlyA, showing that the culture system is specific for megakaryocytic differentiation. The DNA ploidy profile of the CD41a +CD42b + cells generated on Day 17 showed that on average 26% and 9% of cells had 4N and 8N+ DNA ploidy, respectively (n = 11). Multinucleated MKs could also be readily observed by immunofluorescence microscopy. These PSC-derived MKs produced an average of 3.5 PLTs (range: 1 - 10 PLTs, n = 11) based on viable CD41a +CD45 -GlyA - PLT-like particles with a similar size and CD41 expression as control PLTs prepared from fresh blood. In conclusion, we have developed a simple two-step, yet robust serum- and feeder-free culture system for generating high numbers of hPSC-MKs that are large, polyploid, and capable of shedding PLTs. This culture method provides a platform to study thrombopoiesis and is amenable to scale-up method development. Disclosures No relevant conflicts of interest to declare.

PTEN and DNA Ploidy Status by Machine Learning in Prostate Cancer

Machine learning (ML) is expected to improve biomarker assessment. Using convolution neural networks, we developed a fully-automated method for assessing PTEN protein status in immunohistochemically-stained slides using a radical prostatectomy (RP) cohort (n = 253). It was validated according to a predefined protocol in an independent RP cohort (n = 259), alone and by measuring its prognostic value in combination with DNA ploidy status determined by ML-based image cytometry. In the primary analysis, automatically assessed dichotomized PTEN status was associated with time to biochemical recurrence (TTBCR) (hazard ratio (HR) = 3.32, 95% CI 2.05 to 5.38). Patients with both non-diploid tumors and PTEN-low had an HR of 4.63 (95% CI 2.50 to 8.57), while patients with one of these characteristics had an HR of 1.94 (95% CI 1.15 to 3.30), compared to patients with diploid tumors and PTEN-high, in univariable analysis of TTBCR in the validation cohort. Automatic PTEN scoring was strongly predictive of the PTEN status assessed by human experts (area under the curve 0.987 (95% CI 0.968 to 0.994)). This suggests that PTEN status can be accurately assessed using ML, and that the combined marker of automatically assessed PTEN and DNA ploidy status may provide an objective supplement to the existing risk stratification factors in prostate cancer.

The Application of DNA Ploidy Analysis in Large-Scale Population Screening for Cervical Cancer

<b><i>Objective:</i></b> The objective of this study was to evaluate the application of DNA ploidy analysis in large-scale population screening for cervical cancer. <b><i>Methods:</i></b> From March 2016 to March 2019, eligible subjects were enrolled and recommended to undergo DNA ploidy analysis, the ThinPrep cytology test (TCT), and high-risk human papillomavirus (hrHPV) detection concurrently. Patients with positive results were recommended for colposcopy, and biopsy diagnosis was regarded as the “gold standard.” We compared the test efficiencies of the 3 methods and compared the efficiency and accuracy of the TCT in our hospital and the “2-cancer screening” project in Hubei Province during the same period. <b><i>Results:</i></b> Among 20,574 women, the positive rates of DNA ploidy analysis, cytology, and hrHPV testing were 4.01%, 4.71%, and 16.28%, respectively. The sensitivities of these methods for screening for grade 2+ cervical intraepithelial neoplasia were 0.70, 0.68, and 0.96, and their specificities were 0.79, 0.82, and 0.45, respectively. On comparing DNA ploidy analysis with the TCT, there was no significant difference in the sensitivity, specificity, positive predictive value, negative predictive value, and missed diagnosis rate. In opportunistic screening and the 2-cancer screening project, the positive rates of cytology were 4.71% and 2.87%, respectively. And the efficiency and accuracy of the TCT in opportunistic screening were higher than in the 2-cancer screening project. <b><i>Conclusion:</i></b> Therefore, DNA ploidy analysis, which is of low-cost and does not depend on cytopathologists, can replace cytology and be applied in large-scale population screening for cervical cancer.

Cytokinesis regulators as potential diagnostic and therapeutic biomarkers for human hepatocellular carcinoma

Cytokinesis, the final step of mitosis, is critical for maintaining the ploidy level of cells. Cytokinesis is a complex, highly regulated process and its failure can lead to genetic instability and apoptosis, contributing to the development of cancer. Human hepatocellular carcinoma is often accompanied by a high frequency of aneuploidy and the DNA ploidy pattern observed in human hepatocellular carcinoma results mostly from impairments in cytokinesis. Many key regulators of cytokinesis are abnormally expressed in human hepatocellular carcinoma, and their expression levels are often correlated with patient prognosis. Moreover, preclinical studies have demonstrated that the inhibition of key cytokinesis regulators can suppress the growth of human hepatocellular carcinoma. Here, we provide an overview of the current understanding of the signaling networks regulating cytokinesis, the key cytokinesis regulators involved in the initiation and development of human hepatocellular carcinoma, and their applications as potential diagnostic and therapeutic biomarkers.

Association between DNA ploidy and micronucleus frequency in chronic smokers and impact of smoking cessation

Tobacco use may initiate the process of oral carcinogenesis with clinically undetectable changes. Smoking cessation may prevent its progression. The objective of this study was to evaluate the association between DNA ploidy and micronucleus (MN) frequency in chronic smokers. Three groups were evaluated: Smoker Group, Former Smoker Group and Control Group. Exfoliative cytology was performed on the lateral border of the tongue and mouth floor. MN and DNA ploidy analyses were performed, as well as the correlation between the variables. The data showed a difference between the groups for the total MN (p = 0.0227), and the Smoker group had the highest mean (4.22 ± 4.12). The three groups did not differ statistically from each other on ploidy evaluation (p-value > 0.05). There was also an association between aneuploidy and increased MN frequency in the Former Smoker group (p = 0.0036). In conclusion, these results point out that there is a relationship between the frequency of MN and aneuploidy in former smokers. Moreover, smoking cessation, even for a short period of time, may promote the decrease of MN frequency caused by tobacco use.