Regulation of RHOV signaling by interaction with SH3 domain-containing adaptor proteins and phosphorylation by PKA.

RHOV and RHOU are considered atypical Rho-family small GTPases because of the existence of N- and C-terminal extension regions, abnormal GDP/GTP cycling, and post-translational modification. Particularly, RHOV and RHOU both have a proline-rich (PR) motif in the N-terminal region. It has been reported that the PR motif of RHOU interacts with GRB2, a SH3 domain-containing adaptor protein, and regulates its activity through EGF receptor signaling. However, it is unknown whether RHOV, like RHOU, interacts with SH3 domain-containing adaptor proteins. In this study, we investigated the interactions between RHOV and SH3 domain-containing adaptor proteins, including GRB2 and NCK2. The RHOV-induced serum response factor (SRF)-dependent gene transcriptional activity was attenuated in cells co-expressing either GRB2 or NCK2 compared to cells expressing RHOV alone. From the results of experiments using various gene mutants of RHOV and GRB2, it appears that the PR motif of the N-terminal region of RHOV is the crucial binding site for the SH3 domain-containing proteins. Furthermore, we found that Ser25 in the N-terminal region of RHOV is phosphorylated by PKA and that its phosphorylation is suppressed by interaction with NCK2 but not GRB2. We have found a novel regulatory mechanism for the phosphorylation of RHOV and its interaction with SH3 domain-containing adaptor proteins.

Unveiling the vitamin E profile in rice bran extracellular vesicles: evaluation of extraction and preparation methods.

Extracellular vesicles (EVs) are nanoscale entities secreted by various cells, encapsulating various nucleic acids and proteins that play important roles in cellular activities. Although rice bran is known for its richness in phytochemicals such as tocopherol and tocotrienol, the distribution of these compounds within EVs has not been extensively studied. The objective of this study was to detect and analyze the presence of vitamin E in EVs extracted from rice bran. We investigated several EV extraction methods, including rotation, vortex mixing, and ultrasonication, followed by post-extraction techniques such as ultracentrifugation, ultrafiltration, and lyophilization. Vitamin E in the EVs from rice bran was analyzed using LC-FLD. This study is the first to identify tocopherol and tocotrienol in rice bran-derived EVs. Our results indicate that ultracentrifugation followed by rotation is the most effective method for the preparation of rice bran-derived EVs. Notably, the vitamin E profile in EVs varies depending on the preparation method and differs from that in rice bran extracts. The pronounced presence of vitamin E in EVs suggests unique pharmacokinetics and underscores the potential of EVs as carriers for drug delivery systems. This study not only confirms the presence of vitamin E in EVs, but also underscores the potential of EVs and their phytochemical content for therapeutic applications.

Relationship between immune-related adverse events and treatment effectiveness in extensive disease small cell lung cancer.

BACKGROUND: This study aimed to assess the relationship between immune response adverse events (irAEs) and treatment efficacy in patients with extensive disease small cell lung cancer (ED-SCLC). METHODS: We retrospectively evaluated the clinical effects in 40 ED-SCLC patients who had received immune-checkpoint inhibitors (ICIs), platinum agents, and etoposide between September 2019 and September 2021. We identified and compared patients belonging to two groups: irAE and non-irAE. RESULTS: Fifteen patients experienced irAEs, and 25 did not. The median progression-free survival in patients with irAE was longer than that in patients without irAE (12.6 months [95% CI: 6.3-19.3 months] vs. 7.2 months [95% CI: 5.8-7.9 months], p = 0.0108). However, the median overall survival (OS) was similar between irAE and non-irAE groups (27.6 months [95% CI: 15.4-NA] vs. 24.9 months [95% CI: 13.7-NA], p = 0.268). Seven (46.7%) in the irAE group and 20 (80%) in the non-irAE group received sequential therapy. The median OS was prolonged in patients who received first- and second-line therapy than in those who received first-line therapy alone (27.6 months [95% CI: 19.2-NA] vs. 6.6 months [95% CI: 0.3-NA], p = 0.053). Grade ≧ 3 irAEs occurred in five (12.5%) patients. Among them, grade 5 irAEs were observed in two patients, including exacerbation of polymyositis and pulmonary arterial embolism. CONCLUSION: In this study, the development of irAEs did not affect OS in patients with ED-SCLC who received platinum-based agents, etoposide, or ICI therapy. We determined that managing irAEs and administering first- and second-line therapies could contribute to prolonged OS.

Understanding of cell death induced by the constituents of Taxus yunnanensis wood.

The ethanol extract from the wood of Taxus Yunnanensis (TY) induced apoptosis in all cancer cell lines tested, which was mainly due to activation of an extrinsic pathway in human colon cancer DLD-1 cells. The extrinsic pathway was activated by the upregulation of the expression levels of Fas and TRAIL/DR5, which led to the activation of caspase-8. Of note, the machinery of this increase in expression was promoted by the upregulation of MIR32a expression, which silenced MIR34a-targeting E2F3 transcription factor. Furthermore, ectopic expression of MIR32a or siR-E2F3 silencing E2F3 increased Fas and TRAIL/DR5 expression. Thus, the extract activated the extrinsic pathway through the MIR34a/E2F3 axis, resulting in the autocrine and paracrine release of TRAIL, and upregulated expression of death receptors Fas and DR5 in the treated DLD-1 cells, which were functionally validated by Fas immunocytochemistry, and using anti-Fas and anti-TRAIL antibodies, respectively. In vivo, TY showed significant anti-tumor effects on xenografted and syngeneic model mice. The extract may also aid in chemoprevention by selectively making marked tumor cells susceptible to the tumor immunosurveillance system.

Plant hvu-MIR168-3p enhances expression of glucose transporter 1 (SLC2A1) in human cells by silencing genes related to mitochondrial electron transport chain complex I.

Diet is a crucial factor for preventing most diseases. Edible plant extracts are known to contain exosome-like nanoparticles, in which food-derived plant microRNAs are included and may serve as a novel functional component in human health. Here, we demonstrated that hvu-MIR168-3p included in the nanoparticles of rice aleurone cells down-regulated the expression of the genes related to mitochondrial electron transport chain complex I in human cells. Subsequently, hvu-MIR168-3p enhanced protein and RNA expression levels of glucose transporter I and caused a decrease in the blood glucose level, which findings were obtained by in vitro and in vivo experiments, respectively. These findings suggest that a cross-kingdom relationship between plants and humans with respect to hvu-MIR168-3p exists and may contribute to preventive medicine for GLUT1-related dysfunctions including glucose metabolism, aging, and tumor immunology.

Time-related change evaluation of the cerebrospinal fluid using postmortem CT.

PURPOSE: We retrospectively evaluated the cerebro-spinal fluid (CSF) CT density at the lateral ventricle to compare the postmortem intervals in cadavers. MATERIALS AND METHODS: The number of cadavers enrolled in this study was 189 (male 120, female 69). According to the estimated postmortem time, the cadavers were divided into 13 groups (postmortem day 0.5, 1, 1.5, 2, 2.5, 3, 4, 5, 7, 10, 14, 21, 30), and were also re-grouped into 3 groups according to the postmortem time-width: group A (postmortem day 0.5-2.5), group B (day 3-7), and group C (day 10-30). Comparisons between the CSF density and estimated postmortem time were also analyzed. RESULTS: The CSF density was around 20HU up to day 2.5, and it increased gradually after day 3. Day 3 and 4 presented higher CSF density than day 1 and 1.5 (p<0.05). Day 7 presented higher CSF density than day 3 (p<0.05). According to the postmortem time-width, the CSF density increased with postmortem time (p<0.05). The simple linear regression equations presented negative correlation between CSF density and estimated postmortem time, and R(2) was 0.119. CONCLUSION: The CSF density increased, but not linearly, according to the postmortem time, and the 3rd postmortem day was the earliest time allowing the difference to be detected. The CSF density needs further evaluation to enable estimation of the postmortem time.

Selective oxygenation of ring-substituted toluenes with electron-donating and -withdrawing substituents by molecular oxygen via photoinduced electron transfer.

A ring-substituted toluene with an electron-withdrawing substituent, p-tolunitrile, is oxygenated by molecular oxygen to yield the corresponding aldehyde with tetrafluoro-p-dicyanobenzene as a photocatalyst under photoirradiation with an Hg lamp (lambda > 300 nm). The oxygenation of a ring-substituted toluene with an electron-donating substituent, p-xylene, by molecular oxygen is also achieved with 10-methyl-9-phenylacridinium ion as a photocatalyst under visible light irradiation, yielding p-tolualdehyde exclusively as the final oxygenated product. Both the oxygenation reactions are initiated by photoinduced electron transfer from the ring-substituted toluene to the singlet excited state of the photocatalyst. The reason for the high selectivity in the photocatalytic oxygenation of various toluene derivatives by molecular oxygen is discussed on the basis of the photoinduced electron transfer mechanism that does not involve the autoxidation process (radical chain reactions). The reactive intermediates in the photocatalytic cycle are successfully detected as the transient absorption spectra and the electron spin resonance spectra.