Minimal residual disease testing in hematologic malignancies and solid cancer

Minimal residual disease (MRD) assays are of a great value to assess treatment efficacy and may provide prognostic information. This is particularly relevant in the era of targeted therapy where the introduction of MRD monitoring has fundamentally transformed the way in which cancer patients are managed. While MRD guidelines are well-established for chronic myeloid leukemia, acute promyelocytic leukemia and acute lymphoblastic leukemia, areas for continuing development are available. High level of standardization and regular external quality control rounds and recommendations for data interpretation remain essential to improve MRD monitoring. In this review, we describe the different applications of MRD assays in most frequent hematologic malignancies and solid cancer and provide an overview of the strengths and potential weaknesses of each method.     

The Effectiveness of the Nimali Variety of Sri Lankan Punica granatum L. Fruit Extracts on Rhabdomyosarcoma (RD) Cells Concerning the Apoptotic Signaling Pathway

Objective: Pomegranate ,a polyphenol-rich fruit, has been considered as one of the ancient fruits with anticancer effect. Cell cycle arrest is considered as an ordinary factor in human cancer, and apoptosis is the frequent drug target. This study aimed to evaluate the effectiveness of the Nimali variety of Sri Lankan Punica granatum L. fruit extracts on rhabdomyosarcoma (RD) cells concerning the apoptotic signaling pathway. Methods: Antiproliferative activity of aqueous extracts of pomegranate peel, pericarp, was assessed using multiple extraction methods (sonication, microwaving, sonication followed by microwaving, keeping in a waterbath, and boiling at 100ºC). Total protein content, nitric oxide production, LDH, and caspase-8 and caspase-3 activities were analyzed in peel extracts prepared by sonicated or microwave methods. RT-qPCR was performed with intact RNA to explore the apoptotic pathway and gene expression. Results: Peel extracts expressed minimum cell viability in a dose-dependent manner, induced cell death on RD cells. However, sonicated peel extract (SPL) indicated the lowest IC50 of 14.8±2.2 μg/mL comparative to healthy VERO cells (>1,000 μg/mL). A decrease of nitrite content in the supernatant was visualized in the graph plotted against concentration. Furthermore, SPL upregulated caspase-8 and caspase-3 signaling pathways and expression of p21 and p53 genes. Conclusion: The findings highlighted the promising therapeutic potential of SPL to inhibit RD growth and progression and to modulate the caspase-8 and caspase-3, p53, and p21 dependent pathway.     

Critical Aspects Concerning the Development of a Pooling Approach for SARS-CoV-2 Diagnosis Using Large-Scale PCR Testing

The primary approach to controlling the spread of the pandemic SARS-CoV-2 is to diagnose and isolate the infected people quickly. Our paper aimed to investigate the efficiency and the reliability of a hierarchical pooling approach for large-scale PCR testing for SARS-CoV-2 diagnosis. To identify the best conditions for the pooling approach for SARS-CoV-2 diagnosis by RT-qPCR, we investigated four manual methods for both RNA extraction and PCR assessment targeting one or more of the RdRp, N, S, and ORF1a genes, by using two PCR devices and an automated flux for SARS-CoV-2 detection. We determined the most efficient and accurate diagnostic assay, taking into account multiple parameters. The optimal pool size calculation included the prevalence of SARS-CoV-2, the assay sensitivity of 95%, an assay specificity of 100%, and a range of pool sizes of 5 to 15 samples. Our investigation revealed that the most efficient and accurate procedure for detecting the SARS-CoV-2 has a detection limit of 2.5 copies/PCR reaction. This pooling approach proved to be efficient and accurate in detecting SARS-CoV-2 for all samples with individual quantification cycle (Cq) values lower than 35, accounting for more than 94% of all positive specimens. Our data could serve as a comprehensive practical guide for SARS-CoV-2 diagnostic centers planning to address such a pooling strategy.     

Norovirus in feces and nasopharyngeal swab of children with and without acute gastroenteritis symptoms: First report of GI.5 in Brazil and GI.3 in nasopharyngeal swab

BackgroundNoroviruses (NoVs) are an important cause of acute gastroenteritis (AGE), worldwide.ObjectivesTo evaluate the frequency, viral load and molecular profile of NoV in fecal and nasopharyngeal swab samples from hospitalized children, and to determine children’s secretor status.Study designFrom May 2014 to May 2015, 219 children were included in the study, 96 with gastroenteric symptoms and 123 without gastroenteric symptoms. All fecal and nasopharyngeal swab samples were screened by TaqMan RT-qPCR duplex (GI/GII NoV) and quality samples were characterized by genomic sequencing.ResultsNorovirus positivity rate in feces was 15.4% in asymptomatic and 18.8% in the symptomatic group. The median viral loads in feces were 2.69 × 10⁸ GC/g and 4.32 × 10⁷ GC/g from children with or without AGE symptoms, respectively. In nasopharyngeal swab samples, the NoV positivity was 11.4% in symptomatic children, with a median viral load of 2.20 × 10⁷ GC/mL and 6.5% in asymptomatic children, with an average viral load of 1.73 × 10⁶ GC/mL. In only two cases NoV was detected in both samples. A considerable genomic variability was observed in feces, with six genotypes being detected, as follows: GII.4, GII.6, GI.3 and GII.3, GI.2 and GI.5. Two GI.3 was detected in nasopharyngeal swab.ConclusionsOur data reveal considerable NoV frequencies in both nasopharyngeal and fecal samples from symptomatic and asymptomatic children. Higher viral loads were detected in samples from AGE symptomatic children, when compared to asymptomatic children. High genomic variability was observed, with this being the first report of GI.5 NoV in Brazil and of GI.3 in nasopharyngeal swab samples.     

Hepatocyte growth factor-regulated tyrosine kinase substrate (HGS) and guanylate kinase 1 (GUK1) are differentially expressed in GH-secreting adenomas

Pituitary tumors, adenomas in their vast majority, represent around 10–15% of the intracranial neoplasms. Pituitary carcinomas are exceedingly rare. Clinically, these neoplasms cause hormonal dysfunctions, and mass effect symptoms as headache and visual disorders in the case of macroadenomas. Pituitary tumorigenesis is still poorly understood. In order to investigate the expression of cancer-related genes in pituitary tumors, we employed a human cancer cDNA macroarray membrane with 1176 well-characterized human genes related to cancer and tumor biology. We were able to identify several differentially expressed genes, among them hepatocyte growth factor-regulated tyrosine kinase substrate (HGS) and guanylate kinase 1 (GUK1) which were over expressed in a pool of clinically nonfunctioning pituitary adenomas, compared with a spinal cord metastasis of a nonfunctioning pituitary carcinoma. HGS and GUK1 mRNA expression were chosen to be validated by quantitative RT-qPCR, however, only GUK1 had the differential expression confirmed between the adenomas and the metastasis of a pituitary carcinoma. We have also investigated HGS and GUK1 mRNA expressions in a series of 46 pituitary adenomas (18 nonfunctioning, 12 GH-secreting, nine PRL-secreting, and seven ACTH-secreting adenomas). HGS and GUK1 were significantly over expressed in GH-secreting adenomas, compared with ACTH-secreting adenomas and nonfunctioning tumors, and with PRL-secreting adenomas, respectively. We have shown that these genes, involved in tumorigenesis in other tissues, are as well over expressed in the pituitary tumors, however, their role in the oncogenesis of these tumors need to be further investigated.