Clinical and genetic profiles of chinese pediatric patients with catecholaminergic polymorphic ventricular tachycardia

BACKGROUNDS

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a rare but lethal cardiac ion channelopathy. Delayed diagnosis and misdiagnosis remain a matter of concern due to its rarity and insufficient recognition of this disorder, particularly in developing countries like China.

AIMS AND METHODS

We reported six catecholaminergic polymorphic ventricular tachycardia (CPVT) children diagnosed in our center along with a comprehensive review of Chinese pediatric CPVT patients reported in domestic and overseas literature between January 2013 and December 2021 to provide an essential reference for physicians to deepen their understanding of pediatric CPVT.

RESULTS

A total of 95 children with CPVT, including our six patients from 21 medical centers were identified. The median age of symptom onset is 8.7 ± 3.0 years. Diagnosis occurred at a median age of 12.9 ± 6.8 years with a delay of 4.3 ± 6.6 years. Selective beta-blockers (Metoprolol and Bisoprolol) were prescribed for 38 patients (56.7%) and 29 (43.3%) patients received non-selective beta-blocker (Propranolol and Nadolol) treatment. Six patients accepted LCSD and seven received ICD implantation at the subsequent therapy. A total of 13 patients died during the disease course. Of the 67 patients with positive gene test results, variants in RYR2 were 47 (70.1%), CASQ2 were 11 (16.4%), and RYR2 accompanied SCN5A were 7 (10.4%). Patients with CASQ2 gene mutations presented with younger symptom onset age, higher positive family history rate and better prognosis than those with RYR2 mutations.

CONCLUSION

Chinese pediatric patients with CPVT had a poorer prognosis than other cohorts, probably due to delayed/missed diagnosis, non-standard usage of beta-blockers, unavailability of flecainide, and a lower rate of LCSD and ICD implantation.

Virulence and antimicrobial resistance of Shiga toxin-producing Escherichia coli from dairy goat and sheep farms in the Netherlands

AIMS

The aim of our study was to investigate the virulence and resistance of STEC from small ruminants farms in the Netherlands. Moreover, the potential transmission of STEC between animals and humans on farms was evaluated.

METHODS AND RESULTS

From 182 farms, in total 287 unique STEC isolates were successfully recovered from animal samples. In addition, STEC was isolated from eight out of 144 human samples. The most detected serotype was O146:H21, however, among other serotypes also O26:H11, O157:H7 and O182:H25 isolates were present. Whole genome sequencing covering all human isolates and 50 of the animal isolates revealed a diversity of stx1, stx2, and eae sub-types and an additional 57 virulence factors. The assessed antimicrobial resistance phenotype, as determined by microdilution, was concordant with the genetic profiles identified by WGS. WGS also showed that three of the human isolates could be linked to an animal isolate from the same farm.

CONCLUSIONS

The obtained STEC isolates showed great diversity in serotype, virulence and resistance factors. Further analysis by WGS allowed for an in-depth assessment of virulence and resistance factors present and to determine the relatedness of human and animal isolates.

Establishment and drug screening of patient-derived extrahepatic biliary tract carcinoma organoids

BACKGROUND

Patient-derived organoids (PDO) have been proposed as a novel in vitro method of drug screening for different types of cancer. However, to date, extrahepatic biliary tract carcinoma (eBTC) PDOs have not yet been fully established.

METHODS

We collected six samples of gallbladder carcinoma (GBC) and one sample of extrahepatic cholangiocarcinoma (eCCA) from seven patients to attempt to establish eBTC PDOs for drug screening. We successfully established five GBC and one eCCA PDOs. Histological staining was used to compare structural features between the original tissues and cancer PDOs. Whole exome sequencing (WES) was performed to analyze the genetic profiles of original tissues and cancer PDOs. Drug screening, including gemcitabine, 5-fluorouracil, cisplatin, paclitaxel, infigratinib, and ivosidenib, was measured and verified by clinical effects in certain cases.

RESULTS

Different PDOs exhibited diverse growth rates during in vitro culture. Hematoxylin and eosin staining demonstrated that the structures of most cancer PDOs retained the original structures of adenocarcinoma. Immunohistological and periodic acid-schiff staining revealed that marker expression in cancer PDOs was similar to that of the original specimens. Genetic profiles from the four original specimens, as well as paired cancer PDOs, were analyzed using whole exome sequencing. Three of the four PDOs exhibited a high degree of similarity when compared to the original specimens, except for GBC2 PDO, which only had a concordance of 74% in the proportion of single nucleotide polymorphisms in the coding sequence. In general, gemcitabine was found to be the most efficient drug for eBTC treatment, as it showed moderate or significant inhibitory impact on cancer growth. Results from drug screening were confirmed to a certain extent by three clinical cases.

CONCLUSIONS

Our study successfully established a series of eBTC PDOs, which contributed to the field of eBTC PDOs. Additional enhancements should be explored to improve the growth rate of PDOs and to preserve their immune microenvironment.

Genomic profiles and transcriptomic microenvironments in 2 patients with synchronous lung adenocarcinoma and lung squamous cell carcinoma: a case report

Background

Multifocal lung cancers (MLCs) are common in patients newly diagnosed with lung cancer, and histological results of most synchronous MLCs are similar. Few cases with different histology findings have been reported, and no genomic or transcriptomic profiling of this kind of cases were done before. Here, we analyzed genomic and transcriptomic profiles of all lung tumors from 2 patients with synchronous adenocarcinoma and squamous cell carcinoma in the same lung lobe.

Case presentation

Two patients were diagnosed as synchronous adenocarcinoma and squamous cell carcinoma and underwent surgical resection. All 4 tumors showed distinct genomic profiles, therefore were independent primary tumors. Several cancer-associated pathways, such as RTK-RAS pathway and Notch pathway, exhibited different mutated genes in different tumors from the same patient. Several known cancer genes with different mutations, including TP53 and KEAP1, were also detected. Mutation signature analysis demonstrated that the tumor initiation might be related to the transcription coupled nucleotide excision repair process. Two tumors for these 2 patients had loss of heterogeneity (LOH) in HLA genes, showing tumor escaping mechanism. Furthermore, tumor microenvironments showed different patterns in 2 tumors from the same patient. The tumor with more neoantigens and no HLA LOH showed more infiltrating CD8+ T cells and more clonal TCRs, indicating a more active microenvironment.

Conclusions

The lung squamous cell carcinoma and lung adenocarcinoma form the same patient are from independent origins. The genetic profiles and transcriptomic microenvironments are quite different for these 2 tumors. With the same genetic background, the 2 tumors in one patient exhibited different tumor escape mechanisms and immune responses, including HLA LOH and T cell infiltrating and expansion.

An Open-Label, Single-Arm, Two-Stage, Multicenter, Phase II Study to Evaluate the Efficacy of TLC388 and Genomic Analysis for Poorly Differentiated Neuroendocrine Carcinomas

BACKGROUND

The discovery of effective therapeutic options for treating metastatic poorly differentiated neuroendocrine carcinoma (NEC) after prior platinum-based chemotherapy remains elusive. This study analyzed the efficacy of TLC388 (Lipotecan) Hydrochloride, a novel camptothecin analog, for pretreated patients with metastatic NEC.

METHODS

This single-arm, two-stage, phase II clinical trial was conducted at four community and academic centers in Taiwan. Patients aged 20 years or older with confirmed metastatic NEC and who had received prior systemic therapy with etoposide plus cisplatin were enrolled between July 2015 and May 2018. Patients received 40 mg/m² of TLC388 intravenously on days 1, 8, and 15 of a 28-day cycle until disease progression or unacceptable toxic effects. Gene mutations were analyzed by next-generation sequencing.

RESULTS

Twenty-three patients with a median age of 61 (range, 44-73) years, 18 of whom were men (78%), were enrolled. Patients received a median of 2 (range, 0-6) treatment cycles. Among 20 evaluable patients, 3 patients exhibited stable disease and no patient experienced a complete or partial remission, resulting in a disease control rate of 15%. Median progression-free survival was 1.8 (95% confidence interval [CI], 0.4-15) months, and the median overall survival was 4.3 (95% CI, 1.7-15) months. The most common treatment-related hematologic adverse events at grade 3 or higher were leukopenia (22.7%), anemia (31.8%), and thrombocytopenia (18.2%). The most frequent mutated genes in 35 patients with NEC were ARSA, DPYD, HEXB, BRCA1, HPD, MYBPC3, BBS2, IL7R, HSD17B4, and PRODH.

CONCLUSION

TLC388 demonstrates limited antitumor activity in metastatic NEC. ClinicalTrials.gov identifier: NCT02457273.

IMPLICATIONS FOR PRACTICE

Poorly differentiated neuroendocrine carcinomas (NECs) are rare and aggressive. Currently, effective therapeutic options for treating metastatic poorly differentiated NECs beyond platinum-based chemotherapy remain elusive. In this single-arm, multicenter, phase II study, 23 patients with NEC were enrolled and received TLC388 (Lipotecan) Hydrochloride, which is a novel camptothecin analog. The results demonstrated the disease control rate of 15%, the median progression-free survival of 1.8 (95% confidence interval [CI], 0.4-15) months, and the median overall survival of 4.3 (95% CI, 1.7-15) months. Most importantly, several novel genetic mutations and pathways were identified. These results offer the opportunity to develop future treatment strategies in this rare cancer.

Four Genome-Wide Association Studies Identify New Extreme Longevity Variants

The search for the genetic determinants of extreme human longevity has been challenged by the phenotype's rarity and its nonspecific definition by investigators. To address these issues, we established a consortium of four studies of extreme longevity that contributed 2,070 individuals who survived to the oldest one percentile of survival for the 1900 U.S. birth year cohort. We conducted various analyses to discover longevity-associated variants (LAV) and characterized those LAVs that differentiate survival to extreme age at death (eSAVs) from those LAVs that become more frequent in centenarians because of mortality selection (eg, survival to younger years). The analyses identified new rare variants in chromosomes 4 and 7 associated with extreme survival and with reduced risk for cardiovascular disease and Alzheimer's disease. The results confirm the importance of studying truly rare survival to discover those combinations of common and rare variants associated with extreme longevity and longer health span.