Hepatitis B virus envelope L particles form hollow nanoparticles displaying a peptide that is indispensable for liver-specific infection by hepatitis B virus in humans. Here we demonstrate the use of L particles for the efficient and specific transfer of a gene or drug into human hepatocytes both in culture and in a mouse xenograft model. In this model, intravenous injection of L particles carrying the gene for green fluorescent protein (GFP) or a fluorescent dye resulted in observable fluorescence only in human hepatocellular carcinomas but not in other human carcinomas or in mouse tissues. When the gene encoding human clotting factor IX was transferred into the xenograft model using L particles, factor IX was produced at levels relevant to the treatment of hemophilia B. The yeast-derived L particle is free of viral genomes, highly specific to human liver cells and able to accommodate drugs as well as genes. These advantages should facilitate targeted delivery of genes and drugs to the human liver.

It is difficult to say that there is more evidence for cardiac amyloidosis (CA) than for ischemic heart disease. On the other hand, 99 m technetium pyrophosphate ( 99 m Tc-PYP) scintigraphy has been reported to be useful with high sensitivity and specificity, especially in transthyretin (TTR) amyloidosis (ATTR) 1,2 Due to the spread of diagnosis using this method, CA, especially wild-type ATTR (ATTRwt) amyloidosis, which has traditionally been considered a rare disease, is more prevalent than previously assumed, and encountered relatively frequently in daily clinical practice. Furthermore, treatment for not only amyloid light-chain (AL) amyloidosis, but also ATTR, has also progressed rapidly. Tafamidis, a drug that stabilizes the TTR tetramer and suppresses amyloid fibril formation and tissue deposition, was listed and used in Japan in November 2013 for the treatment of peripheral neuropathy in patients with hereditary (variant) ATTR (ATTRv) amyloidosis. In addition, following the results of the 2018 Transthyretin Amyloidosis Cardiomyopathy Clinical Trial (ATTR-ACT), which showed the efficacy of tafamidis for CA, 3 the use of TTR to treat CA was approved in March 2019 in Japan.Needless to say, amyloidosis is a systemic disease, and in Japan, numerous studies have been conducted and medical treatments devised by the Ministry of Health, Labour and Welfare (MHLW)'s "Research Group on Amyloidosis", a research project on intractable disease policy. The present guidelines have been developed in coordination between the MHLW's "Research Group on Amyloidosis", the Japanese Circulation Society (JCS) and cardiology-related societies, the Japanese Society of Amyloidosis, and the Japanese Society of Hematology. Systemic amyloidosis specified by the MHLW as being an incurable disease is classified into the following four types.

No abstract

Hereditary ATTR (ATTRm) amyloidosis (also called transthyretin-type familial amyloid polyneuropathy [ATTR-FAP]) is an autosomal-dominant, adult-onset, rare systemic disorder predominantly characterized by irreversible, progressive, and persistent peripheral nerve damage. TTR gene mutations (e.g. replacement of valine with methionine at position 30 [Val30Met (p.Val50Met)]) lead to destabilization and dissociation of TTR tetramers into variant TTR monomers, which form amyloid fibrils that deposit in peripheral nerves and various organs, giving rise to peripheral and autonomic neuropathy and several non-disease specific symptoms.Phenotypic and genetic variability and non–disease-specific symptoms often delay diagnosis and lead to misdiagnosis. Red-flag symptom clusters simplify diagnosis globally. However, in Japan, types of TTR variants, age of onset, penetrance, and clinical symptoms of Val30Met are more varied than in other countries. Hence, development of a Japan-specific red-flag symptom cluster is warranted. Presence of progressive peripheral sensory-motor polyneuropathy and ≥1 red-flag sign/symptom (e.g. family history, autonomic dysfunction, cardiac involvement, carpal tunnel syndrome, gastrointestinal disturbances, unexplained weight loss, and immunotherapy resistance) suggests ATTR-FAP. Outside of Japan, pharmacotherapeutic options are first-line therapy. However, because of positive outcomes (better life expectancy and higher survival rates) with living donor transplant in Japan, liver transplantation remains first-line treatment, necessitating a Japan-specific treatment algorithm.Herein, we present a consolidated review of the ATTR-FAP Val30Met landscape in Japan and summarize findings from a medical advisory board meeting held in Tokyo on 18th August 2016, at which a Japan-specific ATTR-FAP red-flag symptom cluster and treatment algorithm was developed. Beside liver transplantation, a TTR-stabilizing agent (e.g. tafamidis) is a treatment option. Early diagnosis and timely treatment using the Japan-specific red-flag symptom cluster and treatment algorithm might help guide clinicians regarding apt and judicious use of available treatment modalities.

We carried out molecular cytogenetic characterization of 11 cell lines derived from hepatocellular carcinomas (HCCs) and 51 primary HCCs. Comparative genomic hybridization (CGH) revealed frequent amplification at 13q34, where we had detected amplification in several other types of tumor, including esophageal squamous cell carcinomas (ESC). Previously, we suggested possible involvement of TFDP1, encoding a transcription factor DP-1, in the 13q34 amplification observed in a primary ESC. Therefore, we investigated amplifications and expression levels of 5 genes mapped on the amplified region, including TFDP1, for exploring amplification targets at 13q34 in HCCs. 3 of those genes, TFDP1, CUL4A (cullin 4A), and CDC16 (cell division cycle 16), showed distinct amplification and consequent over-expression in some cell lines. Moreover, each was amplified in 3 or 4 of the 51 primary HCCs, and all 3 were amplified in 2 tumors, in which their expression patterns correlated with amplification patterns. To elucidate the functional role of TFDP1 in HCC, we examined expression levels of genes downstream of TFDP1 with real-time quantitative polymerase chain reaction (PCR). Expression of cyclin E gene (CCNE1) correlated closely with that of TFDP1 in not only cell lines, but also primary tumors. Treatment of HCC cells with the antisense oligonucleotide targeting TFDP1 resulted in down-regulation of CCNE1, suggesting that TFDP1 overexpression led to up-regulation of CCNE1 that encoded a positive regulator for cell cycle G1/S transition. In conclusion, our findings suggest that TFDP1, CUL4A, and CDC16 are probable targets of an amplification mechanism and therefore may be involved, together or separately, in development and/or progression of some HCCs.

Mutant (MT) forms of transthyretin (TTR) cause the most common type of autosomal-dominant hereditary systemic amyloidosis—familial amyloidotic polyneuropathy (FAP). Until 20 years ago, FAP was thought to be an endemic disease, but FAP is known to occur worldwide. To date, more than 130 mutations in the TTR gene have been reported. Genotype-phenotype correlations are seen in FAP, and some variation in clinical presentation is often observed in individual kindreds with the same mutation and even among family members. Of the pathogenic TTR mutations, Val30Met was the first to be identified and is the most frequent known mutation found throughout the world. Studies of patients with FAP amyloidogenic TTR (ATTR) Val30Met documented sensorimotor polyneuropathy, autonomic dysfunction, heart and kidney failure, gastrointestinal tract (GI) disorders, and other symptoms leading to death, usually within 10 years of the onset of disease. Diagnosis is sometimes delayed, especially in patients without a clear family history and typical clinical manifestations, since diagnosis requires various studies and techniques such as histopathology, genetic testing, and mass spectrometry. For treatment of FAP, liver transplantation (LT) reportedly halts the progression of clinical manifestations. Exchange of an FAP patient’s diseased liver with a healthy liver causes MT TTR in the body to be replaced by wild-type (WT) TTR. Although clinical evaluations indicated that progression of other clinical symptoms such as peripheral neuropathy, GI symptoms, and renal involvement usually halted after LT in FAP ATTR Val30Met patients, recent studies suggested that LT failed to prevent progression of cardiac amyloidosis in FAP ATTR Val30Met patients after LT, with this failure reportedly being due to continued formation of amyloid that derived mainly from WT TTR secreted from the transplanted non-mutant liver graft. In recent years, many therapeutic strategies have been proposed, and several ongoing therapeutic trials involve, for example, stabilizers of TTR tetramers (tafamidis and diflunisal) and gene therapies to suppress TTR expression (antisense methods and use of small interfering RNAs). These novel therapies may prove to prevent progression of FAP.

Amyloidosis is a protein conformational disorder with the distinctive feature of extracellular accumulation of amyloid fibrils that come from different proteins. In the ligamentum flavum of the lumbar spine, amyloid deposits were frequently found in elderly patients with lumbar spinal canal stenosis and were at least partially formed by wild-type transthyretin. However, how amyloid deposits in the ligamentum flavum affect lumbar spinal canal stenosis has remained unclear. In this study, we analyzed clinical, pathologic, and radiologic findings of patients with lumbar spinal canal stenosis who had amyloid deposits in the ligamentum flavum. We studied 95 ligamentum flavum specimens obtained from 56 patients with lumbar spinal canal stenosis and 21 ligamentum flavum specimens obtained from 19 patients with lumbar disk herniation. We evaluated histopathologic findings and clinicoradiologic manifestations, such as thickness of the ligamentum flavum and lumbar spinal segmental instability. We found that all 95 ligamentum flavum specimens resected from patients with lumbar spinal canal stenosis had amyloid deposits, which we classified into two types, transthyretin-positive and transthyretinnegative, and that transthyretin amyloid formation in the ligamentum flavum of patients with lumbar spinal canal stenosis was an age-associated phenomenon. The amount of amyloid in the ligamentum flavum was related to clinical manifestations of lumbar spinal canal stenosis, such as thickness of the ligamentum flavum and lumbar spinal segmental instability, in the patients with lumbar spinal canal stenosis with transthyretin-positive amyloid deposits. To our knowledge, this report is the first to show clinicopathologic correlations in transthyretin amyloid deposits of the ligamentum flavum. In conclusion, transthyretin amyloid deposits in the ligamentum flavum may be related to the pathogenesis of lumbar spinal canal stenosis in elderly patients.

Diagnosis in the early stages of hereditary transthyretin (ATTR) amyloidosis is imperative to support timely treatment to prevent or delay disease progression. Genetic testing in the setting of genetic counselling enables identification of carriers of a TTR gene mutation who are therefore at risk of developing TTR-associated disease. Knowledge of different genotypes and how they manifest in symptomatic disease should facilitate development of a structured and targeted approach to enable diagnosis of symptomatic disease in ATTR amyloidosis mutation carriers on the first manifestation of the earliest detectable sign or symptom. A group of experts from across Europe, Israel and Japan met to reach a consensus on such an approach. The proposed approach involves establishing a baseline for key clinical parameters, determination of the timing and frequency of follow-up in TTR mutation carriers based on a predicted age of disease onset, and recognition of the likely initial clinical signs and symptoms aligned with the phenotype of the specific TTR gene mutation and family history. Minimum criteria for diagnosis of symptomatic disease have been agreed, which it is hoped will ensure diagnosis of ATTR amyloidosis at the earliest possible stage in people with a known TTR mutation.