Financial toxicity of informal caregivers of colorectal cancer patients: A cross-sectional study.

PURPOSE: To assess the level of financial toxicity of informal caregivers of colorectal cancer patients and explore the related key influencing factors. METHOD: A descriptive survey design was used in this study. Data were collected from 236 informal caregivers of colorectal cancer patients between March 2023 and July 2023 from a major hospital in central China (Henan province). Potential influence factors of financial toxicity, including basic information, perceived stress, and social support were analyzed using multivariate linear regression. RESULTS: The financial toxicity score of 236 caregivers of colorectal cancer patients was 19.42 ± 9.72. One hundred and fourteen caregivers (accounting for 48.31%) of colorectal cancer patients had high levels of financial toxicity. Financial toxicity scores of caregivers were negatively correlated with perceived stress (r = -0.421, P < 0.001) and positively correlated with social support (r = 0.416, P < 0.001). Our multivariate regression analysis identified some factors that directly affected caregivers' financial toxicity, including caregiver age (t = 2.105, P = 0.036), medical insurance (t = 2.462, P = 0.015), average household income (t = 2.995, P = 0.003), place of residence (t = 2.872, P = 0.004), perceived stress (t = -4.945, P < 0.001), and social support (t = 4.513, P < 0.001). CONCLUSIONS: Caregivers of colorectal cancer patients generally experience a higher level of financial toxicity, which could be eased by lower perceived stress and higher social support. In clinical practice, it is necessary to comprehensively assess the level of financial toxicity of particular caregivers and enact targeted interventions such as increasing communication and actively providing information to address the high medical costs, reducing the detrimental effects of financial toxicity, and improving the quality of colorectal cancer care.

Induced alternative splicing an opportunity to study PCSK9 protein isoforms at physiologically relevant concentrations.

Splice modulating antisense oligomers (AOs) are increasingly used to modulate RNA processing. While most are investigated for their use as therapeutics, AOs can also be used for basic research. This study examined their use to investigate internally and terminally truncated proprotein convertase subtilisin/kexin type 9 (PCSK9) protein isoforms. Previous studies have used plasmid or viral-vector-mediated protein overexpression to study different PCSK9 protein isoforms, creating an artificial environment within the cell. Here we designed and tested AOs to remove specific exons that encode for PCSK9 protein domains and produced protein isoforms at more physiologically relevant levels. We evaluated the isoforms' expression, secretion, and subsequent impact on the low-density lipoprotein (LDL) receptor and its activity in Huh-7 cells. We found that modifying the Cis-His-rich domain by targeting exons 10 or 11 negatively affected LDL receptor activity and hence did not enhance LDL uptake although the levels of LDL receptor were increased. On the other hand, removing the hinge region encoded by exon 8, or a portion of the prodomain encoded by exon 2, have the potential as therapeutics for hypercholesterolemia. Our findings expand the understanding of PCSK9 isoforms and their impact on the LDL receptor and its activity at physiologically relevant concentrations.

Mitochondria-targeted cyclometalated iridium-ß-carboline complexes as potent non-small cell lung cancer therapeutic agents.

Natural products and metals play a crucial role in cancer research and the development of antitumor drugs. We designed and synthesized three new carboline-based cyclometalated iridium complexes [Ir(C-N)2(PPßC)](PF6), where PPßC = N-(1,10-phenanthrolin-5-yl)-1-phenyl-9H-pyrido[3,4-b]indole-3-carboxamide, C-N = 2-phenylpyridine (ppy, Ir1), 2-(2,4-difluorophenyl) pyridine (dfppy, Ir2), 7,8-benzoquinoline (bzq, Ir3), by combining iridium with ß-carboline derivative. These iridium complexes exhibited high potential antitumor effects after being promptly taken up by A549 cells. Accumulating in mitochondria rapidly and preferentially, Ir1-3 caused a series of changes in mitochondrial events, including the loss of mitochondrial membrane potential, the depletion of cellular ATP, and the elevation of reactive oxygen species, leading to significant death of A549 cells. Moreover, the activation of intracellular caspase pathway and apoptosis was further validated to contribute to iridium complexes-induced cytotoxicity. These novel iridium complexes exerted a prominent inhibitory effect on tumor growth in a three-dimensional multicellular tumor spheroid model.

ß-cyclodextrin based nano gene delivery using pharmaceutical applications to treat Wolfram syndrome.

Wolfram syndrome is a rare multisystem autosomal recessive neurodegenerative disorder that affects the brain and central nervous system. Currently, there is no cure or treatment for Wolfram syndrome. Therefore, new techniques are needed to target the loss of the WFS1 gene. Gene therapy approach to introduce a functional gene using a viral or a non-viral vector could be a treatment strategy for Wolfram syndrome 1 (WS1). Viral vectors have therapeutic benefits and greater efficiency; however, they pose a high health risk. Recently pharmaceutical therapeutic research has developed cell-penetrating non-viral nano molecules that could be used as vectors for gene delivery. Among nonviral vectors, the unique properties of ß-cyclodextrin suggest that it can be a promising safe vector for gene delivery.

Wolfram syndrome (WS) is a monogenic disorder where the dysfunction of one specific gene (WFS1 gene) results in many clinical manifestations such as diabetes mellites, diabetes insipidus, deafness and optic atrophy. Management of WS is primarily palliative that focuses on treating the individual symptoms that do not address the underlying genetic defect. Gene therapy is a novel treatment approach, where a functional gene is introduced using a viral or a non-viral vector to replace a non-functional gene, and it can be used as a treatment for WS. Genes are usually delivered via viral or non-viral vectors. However, viral vectors pose safety risks, and non-viral vectors are safe but pose limited efficiency. Therefore, evaluating non-viral vectors has the potential to shed light on the development of an effective and safe non-viral gene therapy vector for neurodegenerative diseases such as WS.

Polyglutamine Ataxias: Our Current Molecular Understanding and What the Future Holds for Antisense Therapies.

Polyglutamine (polyQ) ataxias are a heterogenous group of neurological disorders all caused by an expanded CAG trinucleotide repeat located in the coding region of each unique causative gene. To date, polyQ ataxias encompass six disorders: spinocerebellar ataxia types 1, 2, 3, 6, 7, and 17 and account for a larger group of disorders simply known as polyglutamine disorders, which also includes Huntington's disease. These diseases are typically characterised by progressive ataxia, speech and swallowing difficulties, lack of coordination and gait, and are unfortunately fatal in nature, with the exception of SCA6. All the polyQ spinocerebellar ataxias have a hallmark feature of neuronal aggregations and share many common pathogenic mechanisms, such as mitochondrial dysfunction, impaired proteasomal function, and autophagy impairment. Currently, therapeutic options are limited, with no available treatments that slow or halt disease progression. Here, we discuss the common molecular and clinical presentations of polyQ spinocerebellar ataxias. We will also discuss the promising antisense oligonucleotide therapeutics being developed as treatments for these devastating diseases. With recent advancements and therapeutic approvals of various antisense therapies, it is envisioned that some of the studies reviewed may progress into clinical trials and beyond.

Pyrimidine Biosynthetic Enzyme CAD: Its Function, Regulation, and Diagnostic Potential.

CAD (Carbamoyl-phosphate synthetase 2, Aspartate transcarbamoylase, and Dihydroorotase) is a multifunctional protein that participates in the initial three speed-limiting steps of pyrimidine nucleotide synthesis. Over the past two decades, extensive investigations have been conducted to unmask CAD as a central player for the synthesis of nucleic acids, active intermediates, and cell membranes. Meanwhile, the important role of CAD in various physiopathological processes has also been emphasized. Deregulation of CAD-related pathways or CAD mutations cause cancer, neurological disorders, and inherited metabolic diseases. Here, we review the structure, function, and regulation of CAD in mammalian physiology as well as human diseases, and provide insights into the potential to target CAD in future clinical applications.

Neurodegenerative diseases: a hotbed for splicing defects and the potential therapies.

Precursor messenger RNA (pre-mRNA) splicing is a fundamental step in eukaryotic gene expression that systematically removes non-coding regions (introns) and ligates coding regions (exons) into a continuous message (mature mRNA). This process is highly regulated and can be highly flexible through a process known as alternative splicing, which allows for several transcripts to arise from a single gene, thereby greatly increasing genetic plasticity and the diversity of proteome. Alternative splicing is particularly prevalent in neuronal cells, where the splicing patterns are continuously changing to maintain cellular homeostasis and promote neurogenesis, migration and synaptic function. The continuous changes in splicing patterns and a high demand on many cis- and trans-splicing factors contribute to the susceptibility of neuronal tissues to splicing defects. The resultant neurodegenerative diseases are a large group of disorders defined by a gradual loss of neurons and a progressive impairment in neuronal function. Several of the most common neurodegenerative diseases involve some form of splicing defect(s), such as Alzheimer's disease, Parkinson's disease and spinal muscular atrophy. Our growing understanding of RNA splicing has led to the explosion of research in the field of splice-switching antisense oligonucleotide therapeutics. Here we review our current understanding of the effects alternative splicing has on neuronal differentiation, neuronal migration, synaptic maturation and regulation, as well as the impact on neurodegenerative diseases. We will also review the current landscape of splice-switching antisense oligonucleotides as a therapeutic strategy for a number of common neurodegenerative disorders.

Morpholino Oligomer-Induced Dystrophin Isoforms to Map the Functional Domains in the Dystrophin Protein.

Dystrophin plays a crucial role in maintaining sarcolemma stability during muscle contractions, and mutations that prevent the expression of a functional protein cause Duchenne muscular dystrophy (DMD). Antisense oligonucleotide-mediated manipulation of pre-messenger RNA splicing to bypass Duchenne-causing mutations and restore functional dystrophin expression has entered the clinic for the most common DMD mutations. The rationale of "exon skipping" is based upon genotype-phenotype correlations observed in Becker muscular dystrophy, a milder allelic disorder generally characterized by in-frame deletions and internally truncated but semi-functional dystrophin isoforms. However, there is a lack of genotype-phenotype correlations downstream of DMD exon 55, as deletions in this region are rare and most single exon deletions would disrupt the reading frame. Consequently, the amenability of mutations in this region of the DMD gene to exon skipping strategies remains unknown. Here, we induced "Becker muscular dystrophy-like" in-frame dystrophin isoforms in vivo by intraperitoneal injection of peptide-conjugated phosphorodiamidate morpholino oligomers targeting selected exons. The dystrophin isoform encoded by the transcript lacking exons 56+57 appears to be more functional than that encoded by the 58+59-deleted transcript, as determined by higher dystrophin expression, stabilized ß-dystroglycan, and less severe dystrophic pathology, indicating some potential for the strategy to address Duchenne-causing mutations affecting these exons.

A Splice Intervention Therapy for Autosomal Recessive Juvenile Parkinson's Disease Arising from Parkin Mutations.

Parkin-type autosomal recessive juvenile-onset Parkinson's disease is caused by mutations in the PRKN gene and accounts for 50% of all autosomal recessive Parkinsonism cases. Parkin is a neuroprotective protein that has dual functions as an E3 ligase in the ubiquitin-proteasome system and as a transcriptional repressor of p53. While genomic deletions of PRKN exon 3 disrupt the mRNA reading frame and result in the loss of functional parkin protein, deletions of both exon 3 and 4 maintain the reading frame and are associated with a later onset, milder disease progression, indicating this particular isoform retains some function. Here, we describe in vitro evaluation of antisense oligomers that restore functional parkin expression in cells derived from a Parkinson's patient carrying a heterozygous PRKN exon 3 deletion, by inducing exon 4 skipping to correct the reading frame. We show that the induced PRKN transcript is translated into a shorter but semi-functional parkin isoform able to be recruited to depolarised mitochondria, and also transcriptionally represses p53 expression. These results support the potential use of antisense oligomers as a disease-modifying treatment for selected pathogenic PRKN mutations.

Progress in the molecular pathogenesis and nucleic acid therapeutics for Parkinson's disease in the precision medicine era.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders that manifest various motor and nonmotor symptoms. Although currently available therapies can alleviate some of the symptoms, the disease continues to progress, leading eventually to severe motor and cognitive decline and reduced life expectancy. The past two decades have witnessed rapid progress in our understanding of the molecular and genetic pathogenesis of the disease, paving the way for the development of new therapeutic approaches to arrest or delay the neurodegenerative process. As a result of these advances, biomarker-driven subtyping is making it possible to stratify PD patients into more homogeneous subgroups that may better respond to potential genetic-molecular pathway targeted disease-modifying therapies. Therapeutic nucleic acid oligomers can bind to target gene sequences with very high specificity in a base-pairing manner and precisely modulate downstream molecular events. Recently, nucleic acid therapeutics have proven effective in the treatment of a number of severe neurological and neuromuscular disorders, drawing increasing attention to the possibility of developing novel molecular therapies for PD. In this review, we update the molecular pathogenesis of PD and discuss progress in the use of antisense oligonucleotides, small interfering RNAs, short hairpin RNAs, aptamers, and microRNA-based therapeutics to target critical elements in the pathogenesis of PD that could have the potential to modify disease progression. In addition, recent advances in the delivery of nucleic acid compounds across the blood-brain barrier and challenges facing PD clinical trials are also reviewed.

Precision Medicine through Antisense Oligonucleotide-Mediated Exon Skipping.

Clinical implementation of two recently approved antisense RNA therapeutics - Exondys51® to treat Duchenne muscular dystrophy (Duchenne MD) and Spinraza® as a treatment for spinal muscular atrophy (SMA) - highlights the therapeutic potential of antisense oligonucleotides (ASOs). As shown in the Duchenne and Becker cases, the identification and specific removal of 'dispensable' exons by exon-skipping ASOs could potentially bypass lethal mutations in other genes and bring clinical benefits to affected individuals carrying amenable mutations. In this review, we discuss the potential of therapeutic alternative splicing, with a particular focus on targeted exon skipping using Duchenne MD as an example, and speculate on new applications for other inherited rare diseases where redundant or dispensable exons may be amenable to exon-skipping ASO intervention as precision medicine.

Mutation Analysis of HTRA2 Gene in Chinese Familial Essential Tremor and Familial Parkinson's Disease.

Background. HTRA2 has already been nominated as PARK13 which may cause Parkinson's disease, though there are still discrepancies among these results. Recently, Gulsuner et al.'s study found that HTRA2 p.G399S is responsible for hereditary essential tremor and homozygotes of this allele develop Parkinson's disease by examining a six-generation family segregating essential tremor and essential tremor coexisting with Parkinson's disease. We performed this study to validate the condition of HTRA2 gene in Chinese familial essential tremor and familial Parkinson's disease patients, especially essential tremor. Methods. We directly sequenced all eight exons, exon-intron boundaries, and part of the introns in 101 familial essential tremor patients, 105 familial Parkinson's disease patients, and 100 healthy controls. Results. No exonic variant was identified, while one exon-intron boundary variant (rs2241028) and one intron variant (rs2241027) were detected, both with no clinical significance and uncertain function. There was no difference in allele, genotype, and haplotype between groups. Conclusions. HTRA2 exonic variant might be rare among Chinese Parkinson's disease and essential tremor patients with family history, and HTRA2 may not be the cause of familial Parkinson's disease and essential tremor in China.

A community-based study of risk factors for probable rapid eye movement sleep behavior disorder.

OBJECTIVES: To cross-sectionally explore the potential risk factors for rapid eye movement (REM) sleep behavior disorder (RBD) in a community cohort in Shanghai. METHODS: Based on the validated RBD screening questionnaire (RBDSQ), we identified individuals with probable RBD (pRBD) in 3635 community-dwelling residents (≥50 years old) from an urban community of Shanghai. Potential risk factors of pRBD, including age, sex, smoking, socioeconomic status, obesity, consumption of tea (surrogate for caffeine intake) and alcohol, medications and chronic disease status, were assessed via questionnaire. We used logistic regression to investigate the associations between these studied factors and pRBD after adjusting for age, sex and other studied factors. RESULTS: Based on the RBDSQ score ≥5, 2.70% (3.28% in men and 2.41% in women) participants were considered as pRBD. We found that lower education, presence of head injury, atrial fibrillation, hyperlipidemia, constipation, olfactory disturbance, and imbalance, use of alcoholic beverage, selective serotonin reuptake inhibitor, and benzodiazepine were associated with higher likelihood of having pRBD (P < 0.05 for all). In contrast, male sex, use of coffee or tea, smoking and other factors were not significantly association with altered risk of having pRBD. We did not find significant interaction between sex, age and these factors, in relation to pRBD risk. CONCLUSIONS: In this community-based study of older adults, we identified several potential risk factors for concurrent pRBD, including environmental factors and vascular risk factors.

Mutation analysis of CHCHD2 gene in Chinese Han familial essential tremor patients and familial Parkinson's disease patients.

CHCHD2 is the latest identified Parkinson's disease (PD)-causing gene, and previous studies have reported the same CHCHD2 variant (182C>T, Thr61Ile) in both PD and essential tremor (ET) patients. Whether CHCHD2 gene mutations are involved in both of these diseases remains unclear. We sequenced CHCHD2 gene in 171 familial ET patients, 133 autosomal dominant Parkinson's disease patients, and 211 normal controls. No pathogenic mutations were found, suggesting that CHCHD2 gene may not play a major role in our familial Chinese Han ET and PD patients.

The predictive value of SS-16 in clinically diagnosed Parkinson's disease patients: comparison with (99m)Tc-TRODAT-1 SPECT scans.

BACKGROUND: Dopamine transporter based imaging has high diagnostic performance in distinguishing patients with Parkinson's disease (PD) from patients with non-Parkinsonian syndromes. Our previous study indicated that the "Sniffin' Sticks" odor identification test (SS-16) acts as a valid instrument for olfactory assessment in Chinese PD patients. The aim of the study was to compare the efficacy of the two methods in diagnosing PD. METHODS: Fifty-two PD patients were involved in this study and underwent single photon emission computed tomography (SPECT) imaging using the labeled dopamine transporter radiotracer (99m)Tc-TRODAT-1 to assess nigrostriatal dopaminergic function. Olfactory function was assessed with the "Sniffin' Sticks" odor identification test (SS-16) in all patients who received DAT-SPECT scanning. Statistical analysis (SPSS version 21) was carried out to determine the diagnostic accuracy of SS-16 as well as its correlation with (99m)Tc-TRODAT-1 SPECT, its positive predictive value (PPV), and negative predictive value (NPV). RESULTS: We identified a negative correlation between SS-16 and DAT SPECT (Kappa = 0.269, p = 0.004). By using the (99m)Tc-TRODAT-1 uptake results as the gold standard, the sensitivity and specificity of SS-16 was 56.8 and 37.5 %, respectively. Furthermore, the negative and positive predictive values were calculated as 13.6 and 83.3 %, respectively. CONCLUSIONS: SS-16 would not be used as a diagnostic tool for early stage PD patients. Negative results of SS-16 would not exclude the diagnosis of PD. Further tests are needed for validation.

Effect of a Leucine-rich Repeat Kinase 2 Variant on Motor and Non-motor Symptoms in Chinese Parkinson's Disease Patients.

The G2385R variant of the leucine-rich repeat kinase 2 (LRRK2) is strongly associated with Parkinson's disease (PD) in Asian populations. However, it is still unclear whether the clinical phenotype of PD patients with the G2385R variant can be distinguished from that of patients with idiopathic PD. In this study, we investigated motor and non-motor symptoms of LRRK2 G2385R variant carriers in a Chinese population. We genotyped 1031 Chinese PD patients for the G2385R variant of the LRRK2 gene, and examined the demographic and clinical characteristics of LRRK2 G2385R variant carrier and non-carrier PD patients. LRRK2 G2385R variant carriers were more likely to present the postural instability and gait difficulty dominant (PIGD) phenotype. This variant was also significantly associated with motor fluctuations and the levodopa equivalent dose (LED). G2385R variant carriers had higher REM sleep behavior disorder (RBD) screening questionnaire (RBDSQ) score and more RBD symptoms compared with non-carriers. We concluded that the G2385R variant could be a risk factor for the PIGD phenotype, motor fluctuations, LED values and RBD symptoms.

Methylation status of DJ-1 in leukocyte DNA of Parkinson's disease patients.

BACKGROUND: DJ-1 has been thought as a candidate biomarker for Parkinson's disease (PD). It was found reduced in PD brains, CSF and saliva, although there were conflicting results. How DJ-1 expression may be regulated is not clear. Recently, blood-based DNA methylation represents a highly promising biomarker for PD by regulating the causative gene expression. Thus, in this study, we try to explore whether blood-based DNA methylation of DJ-1 could be used as a biomarker to differentiate PD patients from normal control (NC), and whether DNA methylation could regulate DJ-1 expression in a SH-SY5Y cell model. METHODS: Forty PD patients and 40 NC were recruited in this study. DNA was extracted from peripheral blood leukocytes (PBLs). Methylation status of two CpG islands (CpG1 and CpG2) in promoter region of DJ-1 was explored by bisulfite specific PCR-based sequencing method. Methylation inhibitor 5-Aza-dC was used to treat SH-SY5Y cell line, DJ-1 level was detected in both mRNA and protein level. RESULTS: CpG sites in these two CpG islands (CpG1 and CpG2) of DJ-1 were unmethylated in both PD and NC group. In SH-SY5Y cell model treated by methylation inhibitor, there was no significant change of DJ-1 expression in either mRNA level or protein level. CONCLUSIONS: Our results indicated that DNA methylation inhibitor didn't alter DJ-1 gene expression in SH-SY5Y cell model, and DNA methylation of DJ-1 promoter region in PBLs level might not be an efficient biomarker for PD patients.