A pilot study on the detection of microsatellite instability using long mononucleotide repeats in solid tumors.

Microsatellite instability (MSI) status is a prognostic biomarker for immunotherapy in certain types of cancers, such as colorectal cancers (CRCs) and endometrial cancers (ECs). Tumors that are categorized as having high MSI (MSI-H) express high levels of neoantigens for immune recognition. The typical MSI test measures the length of short mononucleotide repeats (SMR) poly(A) 21-27; however, a limitation of this test is the difficulty in determining the shift size, particularly in endometrial cancer. To investigate an MSI detection assay with improved performance, the present study analyzed the use of poly(A) 40-44 mononucleotide repeats to detect the MSI status of 100 patients with either CRC (n=50) or EC (n=50). Capillary electrophoresis was used to evaluate five long mononucleotide repeat (LMR) markers, including poly(A) 40-A, 40-B, 40-C, 40-D and 44. The concordance rate of the LMR-MSI assay compared with an immunohistochemistry MSI detection assay was 96.0 and 95.1% for CRCs and ECs respectively, with the detection limit of the LMR-MSI assay demonstrated to be 2.5% MSI-H in HCT116 colorectal carcinoma cell lines. The LMR-MSI assay yielded a 95.1% concordance rate in ECs compared with that in the SMR-MSI test (87.8%). The LMR-MSI test identified a significantly higher mean shift size (13 bp) in MSI-H tumors compared with the SMR-MSI test (10 bp), in both EC and CRC tissue samples. Together, the present study suggested that the LMR-MSI test could potentially be a sensitive and practical technology for molecular laboratory testing, particularly in the use of immunotherapy for patients with CRCs and ECs.

Genomic instabilities in hepatocellular carcinoma: biomarkers and application in immunotherapies.

Hepatocellular carcinoma (HCC) is one of the deadliest cancers. For patients with advanced HCC, liver function decompensation often occurs, which leads to poor tolerance to chemotherapies and other aggressive treatments. Therefore, it remains critical to develop effective therapeutic strategies for HCC. Etiological factors for HCC are complex and multifaceted, including hepatitis virus infection, alcohol, drug abuse, chronic metabolic abnormalities, and others. Thus, HCC has been categorized as a "genomically unstable" cancer due to the typical manifestation of chromosome breakage and aneuploidy, and oxidative DNA damage. In recent years, immunotherapy has provided a new option for cancer treatments, and the degree of genomic instability positively correlates with immunotherapy efficacies. This article reviews the endogenous and exogenous causes that affect the genomic stability of liver cells; it also updates the current biomarkers and their detection methods for genomic instabilities and relevant applications in cancer immunotherapies. Including genomic instability biomarkers in consideration of cancer treatment options shall increase the patients' well-being.

A novel smart somatosensory wearable assistive device for older adults' home rehabilitation during the COVID-19 pandemic.

Background: Due to the Coronavirus disease 19 (COVID-19) related social distancing measures and health service suspension, physical activity has declined, leading to increased falling risk and disability, and consequently, compromising the older adult health. How to improve the quality of older adult life has become a crucial social issue. Objective: In traditional rehabilitation, manual and repetitive muscle training cannot identify the patient's rehabilitation effect, and increasing the willingness to use it is not easy. Therefore, based on the usability perspective, this study aims to develop a novel smart somatosensory wearable assistive device (called SSWAD) combined with wireless surface electromyography (sEMG) and exergame software and hardware technology. The older adult can do knee extension, ankle dorsiflexion, and ankle plantar flexion rehabilitation exercises at home. Meanwhile, sEMG values can be digitally recorded to assist physicians (or professionals) in judgment, treatment, or diagnosis. Methods: To explore whether the novel SSWAD could improve the older adult willingness to use and motivation for home rehabilitation, 25 frail older adult (12 males and 13 females with an average age of 69.3) perform the rehabilitation program with the SSWAD, followed by completing the system usability scale (SUS) questionnaire and the semi-structured interview for the quantitative and qualitative analyses. In addition, we further investigate whether the factor of gender or prior rehabilitation experience would affect the home rehabilitation willingness or not. Results: According to the overall SUS score, the novel SSWAD has good overall usability performance (77.70), meaning that the SSWAD makes older adult feel interested and improves their willingness for continuous rehabilitation at home. In addition, the individual item scores of SUS are shown that female older adult with prior rehabilitation experience perform better in "Learnability" (t = 2.35, p = 0.03) and "Confidence" (t = -3.24, p = 0.01). On the contrary, male older adult without rehabilitation experience are more willing to adopt new technologies (t = -2.73, p = 0.02), and perform better in "Learnability" (t = 2.18, p = 0.04) and "Confidence" (t = -3.75, p < 0.001) with the SSWAD. In addition, the result of the semi-structured interview shows that the operation of the SSWAD is highly flexible, thus reducing older adult burden during the rehabilitation exercise and using them long-term. Conclusion: This novel SSWAD receives consistently positive feedback regardless of the gender or prior rehabilitation experience of elders. The SSWAD could be used as a novel way of home rehabilitation for elders, especially during the COVID-19 pandemic. Older adult can do rehabilitation exercises at home, and physicians could make proper judgments or adjust suitable treatments online according to the sEMG data, which older adult can know their rehabilitation progress at the same time. Most importantly, older adult do not have to go to the hospital every time for rehabilitation, which significantly reduces time and the risk of infection.

Enhancing diagnosis of T-cell lymphoma using non-recombined T-cell receptor sequences.

Clonality assessment, which can detect neoplastic T cells by identifying the uniquely recombined T-cell receptor (TCR) genes, provides important support in the diagnosis of T-cell lymphoma (TCL). BIOMED-2 is the gold standard clonality assay and has proven to be effective in European TCL patients. However, we failed to prove its sensitivity in Taiwanese TCL patients, especially based on the TCRß gene. To explore potential impact of genetic background in the BIOMED-2 test, we analyzed TCRß sequences of 21 healthy individuals and two TCL patients. This analysis suggests that genetic variations in the BIOMED-2 primer sites could not explain the difference in sensitivity. The BIOMED-2 test results of the two TCL patients were positive and negative, respectively. Interestingly, a higher percentage (>81%) of non-recombined TCRß sequences was observed in the test-negative patient than those of the test-positive patient and all healthy individuals (13~66%). The result suggests a new TCR target for enhancing TCL diagnosis. To further explore the hypothesis, we proposed a cost-effective digital PCR assay that quantifies the relative abundance of non-recombined TCRß sequences containing a J2-2P~J2-3 segment. With the digital PCR assay, bone marrow specimens from TCL patients (n=9) showed a positive outcome (i.e., the relative abundance of the J2-2P~J2-3 sequences ≧5%), whereas non-TCL patients (n=6) gave a negative result. As five of nine TCL patients had a negative BIOMED-2 test result, the J2-2P~J2-3 sequences may improve TCL detection. This is the first report showing the capability of characterizing non-recombined TCR sequences as a supplementary strategy for the BIOMED-2 clonality test.

Normal cells repel WWOX-negative or -dysfunctional cancer cells via WWOX cell surface epitope 286-299.

Metastatic cancer cells are frequently deficient in WWOX protein or express dysfunctional WWOX (designated WWOXd). Here, we determined that functional WWOX-expressing (WWOXf) cells migrate collectively and expel the individually migrating WWOXd cells. For return, WWOXd cells induces apoptosis of WWOXf cells from a remote distance. Survival of WWOXd from the cell-to-cell encounter is due to activation of the survival IκBα/ERK/WWOX signaling. Mechanistically, cell surface epitope WWOX286-299 (repl) in WWOXf repels the invading WWOXd to undergo retrograde migration. However, when epitope WWOX7-21 (gre) is exposed, WWOXf greets WWOXd to migrate forward for merge. WWOX binds membrane type II TGFß receptor (TßRII), and TßRII IgG-pretreated WWOXf greet WWOXd to migrate forward and merge with each other. In contrast, TßRII IgG-pretreated WWOXd loses recognition by WWOXf, and WWOXf mediates apoptosis of WWOXd. The observatons suggest that normal cells can be activated to attack metastatic cancer cells. WWOXd cells are less efficient in generating Ca2+ influx and undergo non-apoptotic explosion in response to UV irradiation in room temperature. WWOXf cells exhibit bubbling cell death and Ca2+ influx effectively caused by UV or apoptotic stress. Together, membrane WWOX/TßRII complex is needed for cell-to-cell recognition, maintaining the efficacy of Ca2+ influx, and control of cell invasiveness.