Value of a molecular screening program to support clinical trial enrollment in Asian cancer patients: The Integrated Molecular Analysis of Cancer (IMAC) Study.

The value of precision oncology initiatives in Asian contexts remains unresolved. Here, we review the institutional implementation of prospective molecular screening to facilitate accrual of patients into biomarker-driven clinical trials, and to explore the mutational landscape of advanced tumors occurring in a prospective cohort of Asian patients (n = 396) with diverse cancer types. Next-generation sequencing (NGS) and routine clinicopathological assays, such as immunohistochemistry, copy number analysis and in situ hybridization tests, were performed on tumor samples. Actionable biomarker results were used to identify eligibility for early-phase, biomarker-driven clinical trials. Overall, NGS was successful in 365 of 396 patients (92%), achieving a mean depth of 1,943× and coverage uniformity of 96%. The median turnaround time from sample receipt to return of genomic results was 26.0 days (IQR, 19.0-39.0 days). Reportable mutations were found in 300 of 365 patients (82%). Ninety-one percent of patients at study enrollment indicated consent to receive incidental findings and willingness to undergo genetic counseling if required. The most commonly mutated oncogenes included KRAS (19%), PIK3CA (16%), EGFR (5%), BRAF (3%) and KIT (3%); while the most frequently mutated tumor suppressor genes included TP53 (40%), SMARCB1 (12%), APC (8%), PTEN (6%) and SMAD4 (5%). Among 23 patients enrolled in genotype-matched trials, median progression-free survival was 2.9 months (IQR, 1.5-4.0 months). Nine of 20 evaluable patients (45%; 95% CI, 23.1-68.5%) derived clinical benefit, including 3 partial responses and 6 with stable disease lasting ≥ 8 weeks.

Statistical Process Control Charts for Monitoring Next-Generation Sequencing and Bioinformatics Turnaround in Precision Medicine Initiatives.

PURPOSE: Precision oncology, such as next generation sequencing (NGS) molecular analysis and bioinformatics are used to guide targeted therapies. The laboratory turnaround time (TAT) is a key performance indicator of laboratory performance. This study aims to formally apply statistical process control (SPC) methods such as CUSUM and EWMA to a precision medicine programme to analyze the learning curves of NGS and bioinformatics processes. PATIENTS AND METHODS: Trends in NGS and bioinformatics TAT were analyzed using simple regression models with TAT as the dependent variable and chronologically-ordered case number as the independent variable. The M-estimator "robust" regression and negative binomial regression were chosen to serve as sensitivity analyses to each other. Next, two popular statistical process control (SPC) approaches which are CUSUM and EWMA were utilized and the CUSUM log-likelihood ratio (LLR) charts were also generated. All statistical analyses were done in Stata version 16.0 (StataCorp), and nominal P < 0.05 was considered to be statistically significant. RESULTS: A total of 365 patients underwent successful molecular profiling. Both the robust linear model and negative binomial model showed statistically significant reductions in TAT with accumulating experience. The EWMA and CUSUM charts of overall TAT largely corresponded except that the EWMA chart consistently decreased while the CUSUM analyses indicated improvement only after a nadir at the 82nd case. CUSUM analysis found that the bioinformatics team took a lower number of cases (54 cases) to overcome the learning curve compared to the NGS team (85 cases). CONCLUSION: As NGS and bioinformatics lead precision oncology into the forefront of cancer management, characterizing the TAT of NGS and bioinformatics processes improves the timeliness of data output by potentially spotlighting problems early for rectification, thereby improving care delivery.

Nerve regeneration by human corneal stromal keratocytes and stromal fibroblasts.

Laser refractive surgeries reshape corneal stroma to correct refractive errors, but unavoidably affect corneal nerves. Slow nerve regeneration and atypical neurite morphology cause desensitization and neuro-epitheliopathy. Following injury, surviving corneal stromal keratocytes (CSKs) are activated to stromal fibroblasts (SFs). How these two different cell types influence nerve regeneration is elusive. Our study evaluated the neuro-regulatory effects of human SFs versus CSKs derived from the same corneal stroma using an in vitro chick dorsal root ganglion model. The neurite growth was assessed by a validated concentric circle intersection count method. Serum-free conditioned media (CM) from SFs promoted neurite growth dose-dependently, compared to that from CSKs. We detected neurotrophic and pro-inflammatory factors (interleukin-8, interleukin-15, monocyte chemoattractant protein-1, eotaxin, RANTES) in SFCM by Bio-Plex Human Cytokine assay. More than 130 proteins in SFCM and 49 in CSKCM were identified by nanoLC-MS/MS. Proteins uniquely present in SFCM had reported neuro-regulatory activities and were predicted to regulate neurogenesis, focal adhesion and wound healing. Conclusively, this was the first study showing a physiological relationship between nerve growth and the metabolically active SFs versus quiescent CSKs from the same cornea source. The dose-dependent effect on neurite growth indicated that nerve regeneration could be influenced by SF density.

Decellularization of human stromal refractive lenticules for corneal tissue engineering.

Small incision lenticule extraction (SMILE) becomes a procedure to correct myopia. The extracted lenticule can be used for other clinical scenarios. To prepare for allogeneic implantation, lenticule decellularization with preserved optical property, stromal architecture and chemistry would be necessary. We evaluated different methods to decellularize thin human corneal stromal lenticules created by femtosecond laser. Treatment with 0.1% sodium dodecylsulfate (SDS) followed by extensive washes was the most efficient protocol to remove cellular and nuclear materials. Empty cell space was found inside the stroma, which displayed aligned collagen fibril architecture similar to native stroma. The SDS-based method was superior to other treatments with hyperosmotic 1.5 M sodium chloride, 0.1% Triton X-100 and nucleases (from 2 to 10 U/ml DNase and RNase) in preserving extracellular matrix content (collagens, glycoproteins and glycosaminoglycans). The stromal transparency and light transmittance was indifferent to untreated lenticules. In vitro recellularization showed that the SDS-treated lenticules supported corneal stromal fibroblast growth. In vivo re-implantation into a rabbit stromal pocket further revealed the safety and biocompatibility of SDS-decellularized lenticules without short- and long-term rejection risk. Our results concluded that femtosecond laser-derived human stromal lenticules decellularized by 0.1% SDS could generate a transplantable bioscaffold with native-like stromal architecture and chemistry.

Telomere shortening in human diseases.

The discovery of telomeres dates back to the early 20th century. In humans, telomeres are heterochromatic structures with tandem DNA repeats of 5'-TTAGGG-3' at the chromosomal ends. Telomere length varies greatly among species and ranges from 10 to 15 kb in humans. With each cell division, telomeres shorten progressively because of the 'end-replication problem'. Short or dysfunctional telomeres are often recognized as DNA DSBs, triggering cell-cycle arrest and result in cellular senescence or apoptotic cell death. Therefore, telomere shortening serves as an important tumor-suppressive mechanism by limiting cellular proliferative capacity by regulating senescence checkpoint activation. Although telomeres serve as a mitotic clock to cells, they also confer capping on chromosomes, with help from telomere-associated proteins. Over the past decades, many studies of telomere biology have demonstrated that telomeres and telomere-associated proteins are implicated in human genetic diseases. In addition, it has become more apparent that accelerated telomere erosion is associated with a myriad of metabolic and inflammatory diseases. Moreover, critically short or unprotected telomeres are likely to form telomeric fusions, leading to genomic instability, the cornerstone for carcinogenesis. In light of these, this minireview summarizes studies on telomeres and telomere-associated proteins in human diseases. Elucidating the roles of telomeres involved in the mechanisms underlying pathogenesis of these diseases may open up new possibilities for novel molecular targets as well as provide important diagnostic and therapeutic implications.