Real-world therapeutic effectiveness of lorlatinib after alectinib in Japanese patients with ALK-positive non-small-cell lung cancer.

Alectinib, an anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI), is the recommended first-line treatment for ALK-positive non-small-cell lung cancer (NSCLC) in Japan. Lorlatinib was approved as a subsequent therapeutic option after progression while receiving ALK TKI treatment. However, data on the use of lorlatinib in the second- or third-line setting after alectinib failure are limited in Japanese patients. This retrospective real-world observational study investigated the clinical effectiveness of lorlatinib in second- or later-line settings after alectinib failure in Japanese patients. Clinical and demographic data collected in the Japan Medical Data Vision (MDV) database between December 2015 and March 2021 were used. Patients diagnosed with lung cancer who received lorlatinib following alectinib failure after the November 2018 marketing approval of lorlatinib in Japan were included. Of 1954 patients treated with alectinib, 221 were identified from the MDV database as receiving lorlatinib after November 2018. The median age of these patients was 62 years. Second-line lorlatinib treatment was reported for 154 patients (70%); third- or later-line lorlatinib treatment was reported for 67 patients (30%). The median duration of treatment (DOT) for all lorlatinib-treated patients was 161 days (95% confidence interval [CI], 126-248), and 83 patients (37.6%) continued treatment after data cut-off (March 31, 2021). Median DOTs of 147 days (95% CI, 113-242) and 244 days (95% CI, 109 to not reached) were reported with second-line and third- or later-line treatment, respectively. Consistent with clinical trial data, this real-world observational study supports data suggesting the effectiveness of lorlatinib after alectinib failure in Japanese patients.

Overlooked muscle cramps in patients with chronic liver disease: in relation to the prevalence of muscle cramps.

INTRODUCTION: Muscle cramps are common comorbidities in chronic liver disease (CLD). Although the prevalence of these has been reported in patients with liver cirrhosis (LC), that of CLD is unknown. In this study, we aimed to clarify the prevalence and characteristics of muscle cramps in individual CLD. PATIENTS AND METHODS: A total of 432 patients with CLD who visited our hospital were enrolled. The existence of muscle cramps, frequency, time zone, duration, and the degree of pain were investigated using a medical interview questionnaire. RESULTS: The median age of the patients was 65 years and 48.6% of the patients were women. The prevalence of muscle cramps was 25.9%. Age, female sex, lower BMI, existence of comorbid diseases, and liver fibrosis were associated significantly with muscle cramps. In LC, muscle cramps were significantly frequent, and the severity and duration of these were significantly stronger and longer compared with chronic hepatitis. Female sex [odds ratio (OR): 2.26; P=0.014], diabetes (OR: 29.4; P<0.001), chronic kidney disease (OR: 8.33; P=0.004), and lower BMI (OR: 0.853; P<0.001) were independent factors associated with muscle cramps in CLD. Muscle mass indices were significantly lower among nonalcoholic fatty liver disease patients with muscle cramps, female patients, elderly patients, and patients with advanced fibrosis. CONCLUSION: The prevalence of muscle cramps was relatively high in CLD. Female sex, comorbid diabetes, and chronic kidney disease are associated with muscle cramps in CLD. Furthermore, reduced muscle mass is related to muscle cramps in nonalcoholic fatty liver disease.

Biological and Pathological Implications of an Alternative ATP-Powered Proteasomal Assembly With Cdc48 and the 20S Peptidase.

The ATP-powered protein degradation machinery plays essential roles in maintaining protein homeostasis in all organisms. Robust proteolytic activities are typically sequestered within protein complexes to avoid the fatal removal of essential proteins. Because the openings of proteolytic chambers are narrow, substrate proteins must undergo unfolding. AAA superfamily proteins (ATPases associated with diverse cellular activities) are mostly located at these openings and regulate protein degradation appropriately. The 26S proteasome, comprising 20S peptidase and 19S regulatory particles, is the major ATP-powered protein degradation machinery in eukaryotes. The 19S particles are composed of six AAA proteins and 13 regulatory proteins, and bind to both ends of a barrel-shaped proteolytic chamber formed by the 20S peptidase. Several recent studies have reported that another AAA protein, Cdc48, can replace the 19S particles to form an alternative ATP-powered proteasomal complex, i.e., the Cdc48-20S proteasome. This review focuses on our current knowledge of this alternative proteasome and its possible linkage to amyotrophic lateral sclerosis.

Nitrogen:Phosphorus supply ratio may control the protein and total toxin of dinoflagellate Alexandrium tamarense.

The protein and total toxin of dinoflagellate Alexandrium tamarense at the exponential growth phase were studied at four N:P supply ratios=8, 16, 24 and 48 by maintaining the N concentration at 880 microM with variable P concentrations without nutrient limitation. Because A. tamarense grew well at all N:P supply ratios, they might synthesize RNA which contains high phosphorus and consequently low N:P atomic ratio of cells might be retained during exponential growth phase. Cellular protein:C ratio and toxin:C ratio depended on N:P supply ratio, suggesting that intracellular biochemical composition of A. tamarense might vary due to N:P supply conditions. These biochemical changes could not be detected by only investigations of cellular N:C atomic ratio which was independent on N:P supply ratio. Total cellular toxin contents of A. tamarense increased with increasing N:P supply ratio, indicated that total cellular toxin contents of A. tamarense might be stimulated by relative P-deficiency. In situ P concentration of the Seto Inland Sea of Japan has been reduced since 1980s the environmental regulation issued by Japanese Government, and therefore N:P supply ratio of input water from adjacent rivers has became higher than the Redfield ratio. The present study may suggest that the reduction of P supply into ambient sea water might cause A. tamarense to accumulate more toxin within the cell, in result, noxious A. tamarense would be more influential to marine organisms in coastal ecosystem.

Variability in toxicity of the dinoflagellate Alexandrium tamarense in response to different nitrogen sources and concentrations.

Nitrogen (N) supply in pulses was simulated by exposing Alexandrium tamarense which was acclimatized at low N concentration (6 microM-N) to sudden increase in concentrations of nitrate, ammonium and urea, and the variability in toxicity due to nutrient status of A. tamarense was examined. The toxin composition did not vary dramatically among the three N sources, however, ammonium induced the highest concentration of intracellular toxin, followed by urea and then nitrate. Therefore, populations utilizing high ammonium concentration could be more toxic than those growing on nitrate or urea. The toxin content was dependent on the cellular N status of nitrate grown cells only, suggesting that the competition for N in toxin production with other metabolic pathways such as growth may be different among N sources. The relationship between toxin and nutrient status is a complex interaction and it involves the redistribution of cellular N within the cells. Understanding the toxin dynamics of natural populations in relation to nutrient is essential for the mitigation of harmful dinoflagellates in a given coastal ecosystem.