Tyrosine catabolism enhances genotoxic chemotherapy by suppressing translesion DNA synthesis in epithelial ovarian cancer.

Amino acid metabolism has been actively investigated as a potential target for antitumor therapy, but how it may alter the response to genotoxic chemotherapy remains largely unknown. Here, we report that the depletion of fumarylacetoacetate hydrolase (FAH), an enzyme that catalyzes the final step of tyrosine catabolism, reduced chemosensitivity in epithelial ovarian cancer (EOC). The expression level of FAH correlated significantly with chemotherapy efficacy in patients with EOC. Mechanistically, under genotoxic chemotherapy, FAH is oxidized at Met308 and translocates to the nucleus, where FAH-mediated tyrosine catabolism predominantly supplies fumarate. FAH-produced fumarate binds directly to REV1, resulting in the suppression of translesion DNA synthesis (TLS) and improved chemosensitivity. Furthermore, in vivo tyrosine supplementation improves sensitivity to genotoxic chemotherapeutics and reduces the occurrence of therapy resistance. Our findings reveal a unique role for tyrosine-derived fumarate in the regulation of TLS and may be exploited to improve genotoxic chemotherapy through dietary tyrosine supplementation.

ASCT2-mediated glutamine uptake of epithelial cells facilitates CCL5-induced T cell infiltration via ROS-STAT3 pathway in oral lichen planus.

BACKGROUND: Oral lichen planus (OLP) is a chronic inflammatory disease characterized by T cell infiltration at lesion sites. T cell migration is greatly facilitated by chemokines produced by epithelial cells. Studies have noted the potential role of glutamine uptake in OLP and other inflammatory diseases. Here, we investigated the effect of altered glutamine uptake of epithelial cells on T cell infiltration and its underlying mechanisms in OLP. METHODS: Immunohistochemistry was used to identify the expressions of glutamine transporter alanine-serine-cysteine transporter 2 (ASCT2) and C-C motif chemokine ligand 5 (CCL5) in oral tissues of OLP and healthy controls. Human gingival epithelial cells (HGECs) were treated with glutamine deprivation and ASCT2 inhibiter GPNA respectively to detect the expressions of CCL5 and its related signaling molecules. Additionally, we had determined the impact of epithelial cell-derived CCL5 on T-cell migration using a co-culture system in vitro. RESULTS: ASCT2 and CCL5 expressions in OLP were significantly higher than healthy controls and positively correlated with the density of inflammatory infiltrations. Glutamine supplement significantly increased CCL5 production in HGECs, which was effectively inhibited by GPNA. Besides, glutamine could inhibit reactive oxygen species (ROS) production to activate the signal transducer and activator of transcription 3 (STAT3) causing higher expression level of CCL5 in HGECs. Simultaneously, T cell migration could be blocked by anti-CCL5 neutralizing antibody and STAT3 inhibitor stattic in the co-culture system. CONCLUSION: The upregulated ASCT2-mediated glutamine uptake in epithelial cells promotes CCL5 production via ROS-STAT3 signaling, which boosts the T-cell infiltration in OLP lesion.

Ultrasound-Guided Median Nerve Electrical Stimulation to Promote Upper Limb Function Recovery after Stroke.

Peripheral electrical nerve stimulation enhances hand function during stroke rehabilitation. Here, we proposed a percutaneous direct median nerve stimulation guided by ultrasound (ultrasound-guided median nerve electrical stimulation, UG-MNES) and evaluated its feasibility and effectiveness in the treatment of stroke patients with upper limb extremity impairments. Sixty-three stroke patients (2-3 months of onset) were randomly divided into control and UG-MNES groups. Both groups received routine rehabilitation and the UG-MNES group received an additional ultrasound-guided electrical stimulation of the median nerve at 2 Hz, 0.2 ms pulse-width for 20 minutes with gradual intensity enhancement. The Fugl-Meyer Assessment for upper extremity motor function (FMA-UE) was used as the primary outcome. The secondary outcomes were the Functional Test for the Hemiplegic Upper Extremity (FTHUE-HK), Hand Function Rating Scale, Brunnstrom Stages, and Barthel Index scores for motor and daily functions. All the participants completed the trial without any side effects or adverse events during the intervention. After 4 weeks of intervention, the functions of the upper limbs on the hemiplegic side in both groups achieved significant recovery. Compared to the control group, all evaluation indices used in this trial were improved significantly in the UG-MNES group after 2 and 4 weeks of intervention; particularly, the first intervention of UG-MNES immediately improved all the assessment items significantly. In conclusion, the UG-MNES is a safe and feasible treatment for stroke patients with upper limb extremity impairments and could significantly improve the motor function of the affected upper limb, especially in the first intervention. The UG-MNES could be an effective alternative intervention for stroke with upper limb extremity impairments.

Efficacy of sorafenib adjuvant therapy in northwestern Chinese patients with non-metastatic renal-cell carcinoma after nephrectomy: A multicenter retrospective study.

Recent studies have confirmed the efficacy of sorafenib for patients with advanced renal cell carcinoma; however, its efficacy and safety as an adjuvant therapy in patients with non-metastatic and loco-regional renal cell carcinoma after surgery remains controversial. Thus, the aim of the present retrospective study was to evaluate the efficacy of adjuvant sorafenib therapy in such patients from 8 centers in northwestern China that were treated from August 2009 to December 2016.After surgery, the patients (n = 48) received oral sorafenib for 3 months. The control group (n = 48) comprised patients that underwent the same surgery from December 2009 to June 2016 but without adjuvant therapy who were matched 1:1 with the sorafenib group with respect to sex, age, pathological findings, disease stage and grade, operation time, and surgical procedure. The primary outcome compared between the groups was disease-free survival. Adverse events were also recorded to evaluate the safety of sorafenib. The influence of patients' characteristics and laboratory tests on recurrence was analyzed using unconditional logistic regression.Overall, the demographic characteristics of the 2 groups were similar. There was no significant difference in the rate of recurrence (8.3% for sorafenib patients and 6.2% for the matched patients, P = .66) or median disease-free survival between the 2 groups (hazard ratio = 1.561, 95% confidence interval = 0.349-6.987, P = .56). In multiple logistic regression analysis, increased blood urea nitrogen (BUN) emerged as an independent predictor of recurrence risk (P = .02).These results indicate that postoperative sorafenib adjuvant therapy did not achieve the expected beneficial effect, pointing to the need for further studies to evaluate its utility in such cases.

The Relationship Between the Adverse Events and Efficacy of Sorafenib in Patients With Metastatic Renal Cell Carcinoma: A Multicenter Retrospective Study from Northwest China.

The aim of the study is to evaluate the relationship between the adverse events and efficacy of sorafenib in patients with metastatic renal cell carcinoma (mRCC), with a purpose to guide the judgment of efficacy in sorafenib treatment.Eighty-three mRCC patients who received sorafenib therapy at northwest China were studied retrospectively. Univariate and multivariate analyses were performed to correlate tumor response, progression-free survival (PFS), and overall survival (OS) with adverse event types and grades.Among 83 patients who underwent sorafenib therapy, 2 cases (2.4%) had completed response (CR), 14 cases (16.9%) had partial response (PR), 57 cases (68.7%) had stable disease (SD), and 10 cases (12.0%) developed progressive disease (PD). The median PFS and OS were 15.0 and 29.0 months, respectively. The most frequent grade 1 or 2 adverse events included hand-foot syndrome (68.7%), diarrhea (54.2%), and alopecia (51.8%). The most common grade 3 or 4 adverse events were hand-foot syndrome (6.0%), hypertension (4.8%), and diarrhea (3.6%). The frequency and severity of adverse events correlated with tumor response rate (both with P < 0.05). Multivariate analysis showed the independent predictors of better PFS included rash (OR 0.307, 95%CI 0.148-0.636, P = 0.001) and diarrhea (OR 0.391, 95%CI 0.169-0.783, P = 0.008). Elevated transaminase was the independent predictor of poor PFS (OR 2.606, 95%CI 1.299-5.532, P = 0.012). For OS, rash (OR 0.473, 95%CI 0.253-0.886, P = 0.019) and diarrhea (OR 0.321, 95%CI 0.171-0.605, P = 0.000) correlated with better OS.Sorafenib-related adverse events are associated with efficacy in patients with mRCC from northwest China. Rash and diarrhea are independent protective factors of both PFS and OS, and elevated transaminase is an independent risk factor of PFS. A large prospective study is warranted.

Differential therapeutic effects of nateglinide and acarbose on fasting and postprandial lipid profiles: a randomized trial.

BACKGROUND: Dyslipidemia is commonly seen in patients with type 2 diabetes mellitus (T2DM). The current study sought to compare the effects of nateglinide and acarbose, two antihyperglycemic agents, on both fasting and postprandial lipid profiles in Chinese subjects with T2DM. SUBJECTS AND METHODS: For this multicenter, open-label, randomized, active-controlled, parallel-group study, 103 antihyperglycemic agent-naive patients with T2DM were recruited from four hospitals in China. In total, 85 subjects (44 in the nateglinide group, 41 in the acarbose group) with a known complete lipid profile underwent the entire clinical trial and were included in the final analysis. Serum was collected in the fasting state and 30 and 120 min after a standardized meal (postprandial states) to measure the baseline lipid profiles; the same testing was performed upon completion of a 2-week course of nateglinide (120 mg three times a day) or acarbose (50 mg three times a day). RESULTS: Fasting triglyceride (TG) levels were significantly reduced by both nateglinide and acarbose (P<0.001), with acarbose providing a significantly more robust improvement (vs. nateglinide, P=0.005). Additionally, the TG levels at both postprandial times were significantly reduced by acarbose (P<0.001 at 30 min and P=0.002 at 120 min), whereas nateglinide treatment only significantly reduced the 30-min postprandial TG (P=0.029). Neither nateglinide nor acarbose treatment had significant impact on total cholesterol, high-density lipoprotein, low-density lipoprotein, or non-high-density lipoprotein cholesterol. CONCLUSIONS: Compared with nateglinide, acarbose has superior therapeutic efficacy for reducing fasting and postprandial TG levels in patients with T2DM.