Molecular cloning and analysis of the human Tec protein-tyrosine kinase

Mouse Tec is a non-receptor type protein-tyrosine kinase and is highly expressed in many hematopoietic cell lines. To investigate the roles of the Tec kinase in the human hematopoietic system, we isolated cDNAs encoding the human Tec kinase. The human tec cDNAs can encode a peptide of 631 amino acid residues with a calculated molecular mass of 73,624. The predicted human Tec protein is highly homologous to those of the members of the Tec family including mouse Tec type IV (94% homology), mouse Tsk/Itk (60%), and human Btk (57%). The homology between human Tec and other members of the Tec family can be observed not only in the Src homology 3 (SH3), SH2, and kinase domains, but also in the N-terminal unique domain. Northern blot analysis demonstrated that the major transcripts of tec could be detected at 2.6 kb and 3.6 kb in a wide range of human hematopoietic cell lines including myeloid, B-, and T-cell lineages. Interestingly, high expression of the tec gene could be detected in all of the three patients examined with myelodysplastic syndrome. The human tec gene was mapped by fluorescence in situ hybridization (FISH) to chromosome 4p12.

Sofosbuvir/Ribavirin therapy for patients experiencing failure of ombitasvir/paritaprevir/ritonavir + ribavirin therapy: Two cases report and review of literature

BACKGROUND

The effectiveness of sofosbuvir/ribavirin (SOF/RBV) combination therapy, which is one of the 1st-choice therapeutic options for patients with hepatitis C virus (HCV) genotype 2 (HCV-G2) in Japan according to the most recent version of the Japan Society of Hepatology guideline, for patients who experienced failure of the ombitasvir/paritaprevir/ritonavir plus ribavirin (OBV/PTV/r+RBV) combination therapy, which was another option for patients with HCV-G2, is unknown.

CASE SUMMARY

We evaluated the effects of SOF/RBV combination therapy in two patients with genotype 2a who could not achieve a sustained virological response (SVR) by OBV/PTV/r+RBV combination therapy. One patient was complicated with Vogt-Koyanagi-Harada (VKH) disease. Resistance-associated variations before SOF/RBV combination therapy were not detected in two patients. Both patients had an SVR at 12 wk after the treatment (SVR12). Regarding adverse events (AEs), itching, chill, a dull feeling in the throat and cough as well as increase of alanine transaminase level were shown in one patient, while a headache and deterioration of light aversion probably due to the recurrence of VKH disease were shown in the other patients. In addition, the latter patient developed arthralgia and morning stiffness approximately 7 wk after the therapy and turned out to be diagnosed with rheumatoid arthralgia.

CONCLUSION

SOF/RBV therapy might be effective for patients experiencing failure of OBV/PTV/r+RBV therapy, but caution should be taken regarding the AEs.

Adolescents with chronic hepatitis C might be good candidates for direct-acting antiviral therapy

Three Japanese adolescents with chronic hepatitis C were treated by direct-acting antivirals (DAAs). No adverse events or laboratory abnormalities were observed during and after DAA therapy, and a sustained virological response was achieved in all cases. The emotional functioning of the patients and their mothers were improved after DAA therapy.

Small pancreatic lipoma: case report and literature review

Pancreatic lipomas are very rare and only 19 cases have so far been reported. We present a case of small asymptomatic pancreatic lipoma found incidentally in a 45-year-old man with findings of ultrasonography, computed tomography, and magnetic resonance imaging, including fat-suppressed proton-density-weight imaging. We also provide a brief review of the literature.

Successful radical surgery for lymph node metastasis in a patient with hepatocellular carcinoma following atezolizumab plus bevacizumab combination therapy: a case report and literature review

A woman in her early 80 s was followed up in our hospital for chronic hepatitis C after viral eradication. We detected rapid-growing lymph node metastasis of hepatocellular carcinoma (HCC) after treatment with transcatheter arterial chemoembolization and/or radiofrequency ablation. We found that the metastasis was operable, but the size and location of the metastasis obliged the patient to receive pancreatoduodenectomy, which was too invasive. Then we initiated systemic chemotherapy to perform radical minimally invasive surgery. We treated the patient with 3 weekly cycles of atezolizumab 1200 mg plus bevacizumab 15 mg/kg. The patient tolerated the treatment well, and treatment-emergent adverse events included deterioration of hypertension and increased uric protein. After a total of 4 cycles of therapy, abdominal computed tomography findings showed that the metastasis evidently decreased, and a complete response was achieved based on the Revised Response Evaluation Criteria in Solid Tumors (RECIST) guidelines (version 1.1). Seventeen days later, the metastasis was dissected. Subsequently, we confirmed that there was no pathological metastatic lesion in the resected lymph node. Our case is the first report of successful application of the radical therapy to lymph node metastasis of HCC via combination therapy with atezolizumab/bevacizumab.

Extended therapy duration for therapy-refractory hepatitis C patients with genotype 2

We devised an extended 72-wk peginterferon-α-2a/ribavirin therapy regimen for the retreatment of highly intractable cases, i.e., 48-wk peginterferon-α-2b/ribavirin therapy-intractable cases. Although 2 cases achieved a rapid virological response to 72-wk peginterferon-α-2a/ribavirin therapy, 1 case failed to achieve a sustained virological response. Although the reason for this difference in the effectiveness of 72-wk peginterferon-α-2a/ribavirin therapy between the cases was unclear, the rebound phenomenon of serum transaminase after 48-wk peginterferon-α-2b/ribavirin therapy and the resultant lower viral load compared to that before 48-wk peginterferon-α-2b/ribavirin therapy might have influenced the treatment outcome. Thus, it may be beneficial to consider the rebound phenomenon of serum transaminase and the changes in viral load resulting from previous interferon-based therapy and then cautiously determine the indication and the timing of the administration of 72-wk peginterferon-α-2a/ribavirin in highly intractable cases. Further studies should be performed to confirm this strategy.

A Newly Developed Method-Based Xanthine Oxidoreductase Activities in Various Human Liver Diseases

Studies evaluating xanthine oxidoreductase (XOR) activities in comprehensive liver diseases are scarce, and different etiologies have previously been combined in groups for comparison. To accurately evaluate XOR activities in liver diseases, the plasma XOR activities in etiology-based comprehensive liver diseases were measured using a novel, sensitive, and accurate assay that is a combination of liquid chromatography and triple quadrupole mass spectrometry to detect [13C2, 15N2]uric acid using [13C2, 15N2]xanthine as a substrate. We also mainly evaluated the association between the plasma XOR activities and parameters of liver tests, purine metabolism-associated markers, oxidative stress markers, and an inflammation marker. In total, 329 patients and 32 controls were enrolled in our study. Plasma XOR activities were generally increased in liver diseases, especially in the active phase, such as in patients with hepatitis C virus RNA positivity, those with abnormal alanine transaminase (ALT) levels in autoimmune liver diseases, and uncured hepatocellular carcinoma patients. Plasma XOR activities were numerically highest in patients with acute hepatitis B. Plasma XOR activities were closely correlated with parameters of liver tests, especially serum ALT levels, regardless of etiology and plasma xanthine levels. Our results indicated that plasma XOR activity might reflect the active phase in various liver diseases.

Emerging therapeutic strategies for hepatitis C virus infection

The universal prevalence of hepatitis C virus (HCV) infection, which causes chronic hepatitis, cirrhosis, liver failure, and hepatocellular carcinoma, has become a significant health problem worldwide. Interferon-based therapies, the current standard, IFN-based therapies have limited efficacy and undesirable adverse effects. In addition, neither vaccination against HCV nor specific antiviral reagents for HCV are yet available. Thus, a major medical need still exists for novel and more efficacious anti-HCV reagents showing broad-spectrum clinical efficacy with enhanced tolerability. With the progress in our current understanding of the function and regulation of HCV gene products, the three-dimensional structures of virally encoded enzymes and the recent establishment of the HCV-replicon system, several pharmacological targets are being studied for HCV therapy, including cellular receptors mediating HCV entry, factors facilitating HCV replication and assembly, and intracellular pathways. Recently developed mouse models will be very helpful in evaluating the in vivo efficacy of novel antiviral reagents. Currently many novel antiviral drugs are under evaluation in clinical trials. This review will comprehensively discuss the current treatment options and various novel antiviral reagents available. Ongoing clinical studies of promising lead drugs are also reviewed.

Treatment of intermediate-to-advanced unresectable hepatocellular carcinoma is shifting toward a multidisciplinary strategy that includes multiple modalities as needed

In the recent issue of the World Journal of Gastroenterology, Han et al compared the efficacy of and adverse reactions to bevacizumab versus lenvatinib as molecularly targeted agents in combination with interventional therapy and immunotherapy (IMT) to treat intermediate-to-advanced unresectable hepatocellular carcinoma. No significant differences in efficacy or adverse reactions were observed between bevacizumab and lenvatinib. This study is highly promising because in some regions, e.g., Japan, the combination of molecularly targeted therapy with IMT is fixed because of insurance restrictions, and some molecularly targeted agents cannot be combined with IMT. Further studies using these three modalities are expected to be conducted in the future. Additionally, because advanced radiotherapy modalities have recently been established, the number of combinations continues to increase, and further evidence regarding combination therapy, which is the cornerstone of personalized medicine, needs to be accumulated.

Successful treatment of Japanese hemophilia patient co-infected with HIV and HCV genotype 4a by glecaprevir/pibrentasvir therapy

Although direct-acting antiviral (DAA)-based anti-hepatitis C virus (HCV) therapies are very effective for patients with genotypes 1 and 2, evidence of the efficacy of DAA-based therapy for the special population of patients with genotypes 3-6 is insufficient due to the relatively small number of these subjects in Japan. Human immunodeficiency virus (HIV)/HCV-co-infected patients are recommended to be treated as HCV-mono-infected patients by the latest version of the Japan Society of Hepatology guidelines. However, evidence of efficacy in patients with HIV/HCV genotype 3-6 co-infection is insufficient. Currently, HCV genotypes 3-6 can be treated with two DAA-based therapies, including glecaprevir (GLE)/pibrentasvir (PIB) therapy in Japan. We experienced a relatively rare case of a Japanese hemophilia patient co-infected with HIV/HCV genotype 4a. We evaluated resistance-associated substitutions (RASs) against GLE and PIB before GLE/PIB therapy and found that he had no RASs. He was treated with 12 weeks of GLE/PIB therapy and achieved a sustained virologic response at post-treatment weeks 24. Although the treatment was well tolerated, the patient developed hyper-low-density lipoproteinemia that was probably associated with HCV elimination during the therapy. Additional studies are needed to confirm the efficacy and safety of GLE/PIB therapy for this special population in Japan.