Regulator of G protein signalling 18 promotes osteocyte proliferation by activating the extracellular signal­regulated kinase signalling pathway.

Osteocyte function is critical for metabolism, remodelling and regeneration of bone tissue. In the present study, the roles of regulator of G protein signalling 18 (RGS18) were assessed in the regulation of osteocyte proliferation and bone formation. Target genes and signalling pathways were screened using the Gene Expression Omnibus (GEO) database and Gene Set Enrichment Analysis (GSEA). The function of RGS18 and the associated mechanisms were analysed by Cell Counting Kit 8 assay, 5­ethynyl­2'­deoxyuridine assay, flow cytometry, reverse transcription­quantitative PCR, western blotting and immunostaining. Overlap analysis of acutely injured subjects (AIS) and healthy volunteers (HVs) from the GSE93138 and GSE93215 datasets of the GEO database identified four genes: KIAA0825, ANXA3, RGS18 and LIPN. Notably, RGS18 was more highly expressed in peripheral blood samples from AIS than in those from HVs. Furthermore, RGS18 overexpression promoted MLO­Y4 and MC3T3­E1 cell viability, proliferation and S­phase arrest, but inhibited apoptosis by suppressing caspase­3/9 cleavage. Silencing RGS18 exerted the opposite effects. GSEA of GSE93138 revealed that RGS18 has the ability to regulate MAPK signalling. Treatment with the MEK1/2 inhibitor PD98059 reversed the RGS18 overexpression­induced osteocyte proliferation, and treatment with the ERK1/2 activator 12­O­tetradecanoylphorbol­13­acetate reversed the effects of RGS18 silencing on osteocyte proliferation. In conclusion, RGS18 may contribute to osteocyte proliferation and bone fracture healing via activation of ERK signalling.

Wrapping pancreaticojejunostomy using the ligamentum teres hepatis during laparoscopic pancreaticoduodenectomy: a propensity score matching analysis.

BACKGROUND AND OBJECTIVE: It is controversial whether wrapping around the pancreaticojejunostomy (PJ) could reduce the rate of postoperative pancreatic fistula (POPF), especially in laparoscopic pancreaticoduodenectomy (LPD). This study aims to summarize our single-center initial experience in wrapping around PJ using the ligamentum teres hepatis (LTH) and demonstrate the feasibility and safety of this method. METHODS: Patients who underwent LPD applying the procedure of wrapping around the PJ were identified. The cohort was compared to the cohort with standard non-wrapping PJ. A 1:1 propensity score matching (PSM) was performed to compare the early postoperative outcomes of the two cohorts. Risk factors for POPF were determined by using univariate and multivariate logistic regression analysis. RESULTS: Overall, 143 patients were analyzed (LPD without wrapping (n = 91) and LPD with wrapping (n = 52)). After 1:1 PSM, 48 patients in each cohort were selected for further analysis. Bile leakage, DGE, intra-abdominal infection, postoperative hospital stays, harvested lymph nodes, and R0 resection were comparable between the two cohorts. However, the wrapping cohort was associated with significantly less POPF B (1 vs 18, P = 0.003), POPF C (0 vs 8, P = 0.043), and Clavien-Dindo classification level III-V (5 vs 26, P = 0.010). No patients died due to the clinically relevant POPF in the two cohorts. No patients who underwent the LTH wrapping procedure developed complications directly related to the wrapping procedure. After PSM, whether wrapping was an independent risk factor for POPF (OR = 0.202; 95%CI:0.080-0.513; P = 0.001). CONCLUSIONS: Wrapping the LTH around the PJ technique for LPD was safe, efficient, and reproducible with favorable perioperative outcomes in selected patients. However, further validations using high-quality RCTs are still required to confirm the findings of this study.

Prognostic value of preoperative prealbumin levels in patients with unresectable hepatocellular carcinoma undergoing transcatheter arterial chemoembolisation.

Background: This retrospective study analyzed the prognostic value of preoperative prealbumin (PAB) levels in patients with unresectable hepatocellular carcinoma (HCC) after transcatheter arterial chemoembolisation (TACE). Methods: Four hundred and two patients diagnosed with unresectable HCC were included in this retrospective study. All patients underwent their first TACE procedure. Based on PAB levels before the first TACE, 402 patients were classified as having low PAB levels and high PAB levels. Potential confounding factors between the two groups were eliminated using. Propensity Score Matching (PSM) analysis. The time to progression (TTP) and overall survival (OS) of the two groups were compared using Kaplan-Meier curves before and after PSM. Risk factors for poor prognosis were determined using univariate and multivariate Cox proportional hazards models. Results: Before PSM, the high PAB level group had a significantly longer median TTP and OS than the low PAB level group (all P values < 0.0001). After PSM, the high PAB level group still had a significantly longer median TTP and OS than the low PAB level group (all P values < 0.05). After PSM, low PAB level was found to be an independent predictor of shorter OS (HR = 0.656; 95% CI:0.448-0.961; P = 0.03). The subgroup analysis before PSM showed that low PAB levels increased the risk of poor prognosis in most subgroups. Conclusions: Low preoperative PAB levels are associated with poor prognosis in patients with unresectable HCC after TACE.

A single-center initial experience on laparoscopic pancreatic operation combined with hepatic arterial resection and reconstruction.

Objective: This study aims to summarize our single-center initial experience in laparoscopic pancreatic operation (LPO) combined with hepatic arterial resection and reconstruction, as well as to demonstrate the feasibility, safety, and key surgical procedure for LPO. Methods: We retrospectively analyzed 7 patients who had undergone LPO combined with hepatic arterial resection and reconstruction in our center from January 2021 to December 2022. The clinical data of these 7 patients were collected and analyzed. Results: In our case series, two patients underwent passive arterial resection and reconstruction due to iatrogenic arterial injury, and five patients underwent forward arterial resection and reconstruction due to arterial invasion. The arterial anastomosis was successful in 5 cases, including 2 cases of end-to-end in situ and 3 cases of arterial transposition, and the vascular reconstruction time was 38.28 ± 15.32 min. There were two conversions to laparotomy. The postoperative recovery of all patients was uneventful, with one liver abscess (Segment 4) and no Clavien III-IV complications. We also share valuable technical feedback and experience gained from the initial practice. Conclusions: Based on the surgeon's proficiency in open arterial resection and reconstruction and laparoscopic technique. This study demonstrated the feasibility of total laparoscopic hepatic arterial resection and reconstruction in properly selected cases of arterial involvement or iatrogenic arterial injury. Our initial experience provides valuable information for laparoscopic pancreas surgery with arterial resection and reconstruction.

PNI-Based Nomograms to Predict Tumor Progression and Survival for Patients with Unresectable Hepatocellular Carcinoma Undergoing Transcatheter Arterial Chemoembolization.

BACKGROUND: The relationship between the prognostic nutritional index (PNI) and the prognosis of malignancy has been increasingly mentioned in recent research. This study aimed to construct nomograms based on the PNI to predict tumor progression and survival in patients with unresectable hepatocellular carcinoma (HCC) undergoing transcatheter arterial chemoembolization (TACE). MATERIALS AND METHODS: The development set included 785 patients who underwent their first TACE between 2012 and 2016, and the validation set included 336 patients who underwent their first TACE between 2017 and 2018. The clinical outcomes included the time to progression (TTP) and overall survival (OS). Cox regression was applied to screen for independent risk factors of TTP and OS in the development set, and PNI-based nomograms were constructed for TTP and OS. The predictive performance of nomograms was conducted through the C-index, calibration curves, and decision analysis curves in the development set and validation set. RESULTS: After multivariate analysis, the prognostic predictors of both TTP and OS included portal vessel invasion, extrahepatic metastasis, tumor number, alpha-fetoprotein (AFP) level, longest tumor diameter, and PNI. Furthermore, the Child-Pugh classification and platelets (PLTs) were independent risk factors for OS only. Nomograms for predicting TTP and OS were constructed using TTP and OS prognostic factors. In the development set and the validation set, the C-index of the TTP nomograms was 0.699 (95% confidence interval (CI): 0.680-0.718) and 0.670 (95%CI: 0.638-0.702), and the C-index of the OS nomograms was 0.730 (95%CI: 0.712-0.748) and 0.700 (95%CI: 0.665-0.723), respectively. CONCLUSION: Nomograms based on the PNI can effectively predict tumor progression and survival in patients with unresectable HCC undergoing TACE.

Comparative proteomic analysis of wild-type and a SlETR-3 (Nr) mutant reveals an ethylene-induced physiological regulatory network in fresh-cut tomatoes.

Ethylene plays a crucial role in regulating fruit ripening, quality, and defense response. However, the mechanism(s) responsible for wound-induced ethylene regulation of fruit physiology at a network level is unclear. We used mass spectrometry (MS) to identify differences in the physiological response between fresh-cut fruits of wild-type (WT) tomato and an ethylene receptor mutant (SlETR-3) (also referred to as Nr) during storage. We found that Nr mutants exhibited better appearance and quality, as well as higher ethylene levels during the first 3 d of storage at 4 °C. Thirty-seven (0 h), eighty-two (12 h) and twelve (24 h) differentially abundant proteins were identified between the fresh-cut slices of the two genotypes during storage at the designated timepoints. In particular, antioxidant enzymes, such as ascorbate peroxidase, glutathione S-transferase, and peroxiredoxin were highly expressed in WT fruit, which was associated with higher H2O2 production, and high levels of transcription of cell-wall degrading enzymes. Leucine aminopeptidase, a marker enzyme for response to wounding exhibited higher levels in the Nr mutant, which is consistent with its higher production of ethylene. Collectively, our results provide a deeper insight into the ethylene-induced physiological regulatory network that is activated in fresh-cut tomatoes.

Itaconate alleviates ß2-microglobulin-induced cognitive impairment by enhancing the hippocampal amino-ß-carboxymuconate-semialdehyde-decarboxylase/picolinic acid pathway.

ß2-microglobulin (B2M) has been established to impair cognitive function. However, no treatment is currently available for B2M-induced cognitive dysfunction. Itaconate is a tricarboxylic acid (TCA) cycle intermediate that exerts neuroprotective effects in several neurological diseases. The amino-ß-carboxymuconate-semialdehyde-decarboxylase (ACMSD)/picolinic acid (PIC) pathway is a crucial neuroprotective branch in the kynurenine pathway (KP). The present study sought to investigate whether Itaconate attenuates B2M-induced cognitive impairment and examine the mediatory role of the hippocampal ACMSD/PIC pathway. We demonstrated that 4-Octyl Itaconate (OI, an itaconate derivative) significantly alleviated B2M-induced cognitive dysfunction and hippocampal neurogenesis impairment. OI treatment also increased the expression of ACMSD, elevated the concentration of PIC, and decreased the level of 3-HAA in the hippocampus of B2M-exposed rats. Furthermore, inhibition of ACMSD by TES-991 significantly abolished the protections of Itaconate against B2M-induced cognitive impairment and neurogenesis deficits. Exogenous PIC supplementation in hippocampus also improved cognitive performance and hippocampal neurogenesis in B2M-exposed rats. These findings demonstrated that Itaconate alleviates B2M-induced cognitive impairment by upregulation of the hippocampal ACMSD/PIC pathway. This is the first study to document Itaconate as a promising therapeutic agent to ameliorate cognitive impairment. Moreover, the mechanistic insights into the ACMSD/PIC pathway improve our understanding of it as a potential therapeutic target for neurological diseases beyond B2M-associated neurocognitive disorders.

Evaluation of Walking Comfort in Children's School Travel at Street Scale: A Case Study in Tianjin (China).

(1) Background: school travel is an important part of a child's daily activities. A comfortable walking environment can encourage children to walk to school. The existing methods of evaluating walking environments are not specific to children's walks to school. (2) Methods: this study proposes a method of evaluating walking comfort in children traveling to school at street scale. Related indexes were selected that reflect children's school travel behavior and their needs in street environments based on walking environment audit tools. Factor analysis was then used to calculate the relative weight of each index. (3) Results: the new evaluation method was tested in the neighborhoods around the First Central Primary School in Hedong District, Tianjin, China. The walking comfort for children's school travel was evaluated in eight indexes: effective street width; street flatness; street cleanliness; interface diversity; buffer; shade coverage; green looking ratio; and sound decibels. Different classes and types of streets were found to have various vulnerabilities. (4) Conclusions: this evaluation method can accurately locate the weak spots in streets to improve the local policymakers' perception of street environments, which can greatly facilitate the implementation of precise measures to promote children walking to school.

Evaluation and Optimization of Walkability of Children's School Travel Road for Accessibility and Safety Improvement.

(1) Background: In the context of a children friendly city, accessibility and safety are the basic needs of children's pedestrian school travel. This study proposes a comprehensive evaluation method of pedestrian accessibility and safety for children's school travel. (2) Methods: Firstly, the school travel network was constructed by simulating the path of children walking to school. Secondly, from the meso and micro dimensions, the impact factors of pedestrian accessibility and safety were combed out, and an evaluation index system was constructed. Finally, pedestrian accessibility and safety were evaluated based on the Space Syntax analysis and ArcGIS spatial analysis, and the results were superimposed and spatially differentiated. The new evaluation method was tested in the Jintang Road area in Hedong District, Tianjin, China. (3) Results: The pedestrian accessibility and safety of children's school travel road in the study area needed to be improved. It was found that the main impact factors were the effective walking width, the spatial connectivity, the visual integration, the obstruction of pedestrian safety, the completeness of crossing facilities and the influence of traffic flow and put forward optimization strategies. After optimized simulation verification, the overall improvement was achieved. (4) Conclusion: The evaluation method is helpful to calculate the pedestrian accessibility and safety of children's school travel, and help decision makers determine the design and management strategies of child-friendly streets.

Systematic analysis of immune-related genes based on a combination of multiple databases to build a diagnostic and a prognostic risk model for hepatocellular carcinoma.

The immune microenvironment plays a vital role in the progression of hepatocellular carcinoma (HCC). Thousands of immune-related genes (IRGs) have been identified, but their effects on HCC are not fully understood. In this study, we identified the differentially expressed IRGs and analyzed their functions in HCC in a systematic way. Furthermore, we constructed a diagnostic and a prognostic model using multiple statistical methods, and both models had good distinguishing performance, which we verified in several independent datasets. This diagnostic model was also adaptable to proteomic data. The combination of a prognostic risk model and classic clinical staging can effectively distinguish patients in high- and low-risk groups. Furthermore, we systematically explore the differences in the immune microenvironment between the high-risk group and the low-risk group to help clinical decision-making. In summary, we systematically analyzed immune-related genes in HCC, explored their functions, constructed a diagnostic and a prognostic model and investigated potential therapeutic schedules in high-risk patients. The model performance was verified in multiple databases. Our findings can provide directions for future research.

Anti-CD206 antibody-conjugated Fe3O4-based PLGA nanoparticles selectively promote tumor-associated macrophages to polarize to the pro-inflammatory subtype.

M2 macrophages serve roles in inhibiting inflammation and promoting tumor development. Reversing tumor-associated macrophages (TAMs) from M2- to M1-type polarization may provide an important strategy for tumor immunotherapy. The present study aimed to enhance antitumor immunity by targeting the concentration of iron in macrophages. Fe3O4-based poly(lactic-co-glycolic) acid (PLGA) nanoparticles surface-modified with an anti-CD206 monoclonal antibody were prepared using the oil in water single-emulsion technique. Particle size was measured using a particle size analyzer, the ζ potential was determined using a ζ potential analyzer and the carrier rate of Fe3O4 was measured using an iron assay kit. The conjugation of anti-CD206, and the ability to target M2 macrophages were studied via immunofluorescence. Polarization indexes of the macrophages were detected using both western blotting and reverse transcription-quantitative PCR (RT-qPCR), and a mouse model with subcutaneous tumors was established to verify the antitumor effects of the nanoparticles in vivo. Nanoparticles had a mean diameter in the range of 260-295 nm, and the ζ potential values were between -19 and -33 mV. The Fe3O4 association efficiency ranged from 65-75%, whereas the anti-CD206 conjunction efficiency ranged from 65-70%. The immunofluorescence experiments were able to demonstrate the successful targeting of the M2 macrophages. The western blotting and RT-qPCR experiments identified that CD206-Fe3O4-PLGA and Fe3O4-PLGA promoted the expression of TNF-α, inducible nitric oxide synthase (iNOS) and IL-1ß in the macrophages. The in vivo studies indicated that CD206-Fe3O4-PLGA nanoparticles were able to promote CD86 expression in TAMs, with CD86 being a specific marker of the M1 subtype. In summary, nanoparticles were characterized in the present study by their mean particle size, polydispersity index, ζ potential and morphology, as well as by their association with Fe3O4 and conjugation with the anti-CD206 monoclonal antibody. Collectively, the present results suggested that the nanoparticles were able to both target M2 macrophages and reverse the M2 polarization of the macrophages to the M1 phenotype via the release of coated iron-oxide particles.

[Internal and external fixation combined with second stage perforator flap for the treatment of ankle fracture dislocation of Gustilo-Anderson types â ¢B and â ¢ C].

OBJECTIVE: To explore clinical effect of internal and external fixation combined with second-stage perforator fiap for the treatment of ankle fracture dislocation of Gustilo-Anderson types ⅢB and ⅢC. METHODS: From May 2014 to July 2017, 20 patients with Gustilo-Anderson types ⅢB and ⅢC ankle fracture dislocation were treated with internal and external fixation combined with second-stage perforator fiap, including 14 males and 6 females, aged from 18 to 58 years old with an average of (39.0±9.7) years old;17 patients were type ⅢB and 3 patients were type ⅢC according to Gustilo-Anderson classification;4 patients were type A, 7 patients were type B, and 9 patients were type C according to AO classification. The size of wound ranged from 4 cm×3 cm to 20 cm×9 cm. Second-stage perforator flap, 11 patients were performed with posterior tibial artery perforator flap, 5 patients were performed with fibular artery perforator flap, 1 patient was performed with anterior ankle flap, and 3 patients were performed with posterior tibial artery perforator flap combined with fibular artery perforator flap. Postoperative wound healing, flap survival and fracture healing were observed, AOFAS score was used to evaluate at the latest follow up. RESULTS: All limbs were preserved successfully without amputation. Nine patients occurred superficial infection without deep infection and osteomyelitis occurring. The flaps of 19 patients survived. All patients were followed up for 6 to 18 months with an average of (12.0±2.9) months. The flaps healed well without sinus tract, bone exposure and bone disunion occurring. Fracture healing time ranged from 4 to 10 months with an average of (6.6±1.7) months. PostoperativeAOFAS score was 76.7± 16.4, among which 4 patients got excellent result, 11 patients good, 3 patients fair, and 2 poor. CONCLUSION: Internal and external fixation combined with second stage perforator fiap for the treatment of ankle fracture dislocation of Gustilo-Anderson types ⅢB and ⅢC could effectively close the wound, improve fracture healing and restore appearance and function of limbs to the maximum.

Hydrogen Sulfide Prevents Sleep Deprivation-Induced Hippocampal Damage by Upregulation of Sirt1 in the Hippocampus.

Sleep deprivation (SD) induces hippocampal damage. Hydrogen sulfide (H2S) is a neuronal protective factor. Silence information regulating factor 1 (Sirt1) plays an important role in neuroprotection. Therefore, this study was aimed at exploring whether H2S meliorates SD-induced hippocampal damage and whether Sirt1 mediates this protective role of H2S. We found that sodium hydrosulfide (NaHS, a donor of H2S) alleviated SD-generated hippocampal oxidative stress, including increases in the activation of SOD and the level of GSH as well as a decrease in the level of MDA. Meanwhile, we found that NaHS reduced SD-exerted hippocampal endoplasmic reticulum (ER) Stress, including downregulations of GRP78, CHOP, and cleaved-caspase-12 expression. Moreover, NaHS reduced the apoptosis in the SD-exposed hippocampus, and this included decreases in the number of apoptotic cells and the activation of caspase-3, downregulation of Bax expression, and upregulation of Bcl-2 expression. NaHS upregulated the expression of Sirt1 in the hippocampus of SD-exposed rats. Furthermore, Sirtinol, the inhibitor of Sirt1, abrogated the protection of NaHS against SD-exerted hippocampal oxidative stress, ER stress, and apoptosis. These results suggested that H2S alleviates SD-induced hippocampal damage by upregulation of hippocampal Sirt1.

Impact of salinity on anaerobic microbial community structure in high organic loading purified terephthalic acid wastewater treatment system.

To investigate the effect of salinity (1% sodium chloride) on anaerobic microbial community structure in high strength telephthalic wastewater treatment system, the performances of anaerobic-aerobic process and the shifts of microbial community in anaerobic tank were studied and determined. Results showed that the chemical oxygen demand (COD) removal in the whole process remained above 90%. And the effluent concentrations of targeted pollutants were lower than 10 mg/L, other than para-toluic acid (PT, 38.09 mg/L). However, methane production significantly decreased compared to no salinity situation. This might be due to the inhibition of salinity on methanogens, which hindered the conversion of acetate to methane. Furthermore, the dominant genus in bacterial level changed from Tepidisphaera to Syntrophus, which facilitated the syntrophic association with hydrogenotrophic methanogens. The prevailed archaea remained acetoclastic Methanothrix above 90%. Therefore, the salinity on anaerobic microbial community structure mainly reflects in the methanogen process, remarkably decreasing methane production.

Research Status of Mesenchymal Stem Cells in Liver Transplantation.

Liver transplantation has been deemed the best choice for end-stage liver disease patients but immune rejection after surgery is still a serious problem. Patients have to take immunosuppressive drugs for a long time after liver transplantation, and this often leads to many side effects. Mesenchymal stem cells (MSCs) gradually became of interest to researchers because of their powerful immunomodulatory effects. In the past, a large number of in vitro and in vivo studies have demonstrated the great potential of MSCs for participation in posttransplant immunomodulation. In addition, MSCs also have properties that may potentially benefit patients undergoing liver transplantation. This article aims to provide an overview of the current understanding of the immunomodulation achieved by the application of MSCs in liver transplantation, to discuss the problems that may be encountered when using MSCs in clinical practice, and to describe some of the underlying capabilities of MSCs in liver transplantation. Cell-cell contact, soluble molecules, and exosomes have been suggested to be critical approaches to MSCs' immunoregulation in vitro; however, the exact mechanism, especially in vivo, is still unclear. In recent years, the clinical safety of MSCs has been proven by a series of clinical trials. The obstacles to the clinical application of MSCs are decreasing, but large sample clinical trials involving MSCs are still needed to further study their clinical effects.

Retraction Note: MicroRNA-31-5p regulates chemosensitivity by preventing the nuclear location of PARP1 in hepatocellular carcinoma.

The authors are retracting this article [1] because it overlaps significantly with a previously published article by Moody et al. [2] without proper citation. All authors agree with this retraction.

Peroneus Longus Tendon Autograft is a Safe and Effective Alternative for Anterior Cruciate Ligament Reconstruction.

The ipsilateral peroneus longus tendon (PLT) was utilized as an autograft for anterior cruciate ligament (ACL) reconstruction of patients with acute ACL rupture and grade III medial collateral ligament (MCL) injury. We investigated the efficacy and safety of this alternative autograft compared with autologous hamstring tendon (HT). Biomechanical testing of the graft options was performed and compared with the native ACL. Thirty-eight patients with acute ACL ruptures and grade III MCL injuries were treated with ACL reconstruction with a doubled autologous PLT or quadrupled autologous HT. Knee stability and function was evaluated clinically with the Lachman test and KT-2000 arthometer as well as subjectively with functional scores. Effects on the donor ankle were evaluated by biomechanical testing. The ultimate tensile strengths of doubled PLT and quadrupled HT were significantly higher than that of the native ACL and the ultimate tensile strength of doubled PLT was comparable with that of quadrupled HT. There were no significant differences in clinical or functional scores between the two groups. There were no significant differences in pre- and postoperative biomechanical testing of the donor ankle. PLT is a suitable alternative autograft for an ACL reconstruction in patients with a concomitant grade III MCL injury without a significant biomechanical disadvantage to the ankle donor site.

Supersonic gas flow for preparation of ultrafine silicon powders and mechanochemical synthesis.

We report the supersonic gas flow for crush and mechanochemical synthesis. The key instrument parameters for production of supersonic particle flow, such as annular nozzle, expansion angle and length of the accelerating duct, are theoretically designed and optimized. Based on the theoretical results, supersonic gas flow equipment is fabricated. The capacity of the present equipment for production of supersonic particle flow is demonstrated by particle image velocimetry measurement, and the maximum transient velocity of the particles achieves as much as 550 m s-1. Additionally, the present equipment is applied for continuous and physical preparation of ultrafine Si powders with a high scalability and mechanochemical synthesis of TiO2 and TiNx nanopowders at a high production rate.

MicroRNA-31-5p regulates chemosensitivity by preventing the nuclear location of PARP1 in hepatocellular carcinoma.

BACKGROUND: MicroRNAs (miRNAs) posttranscriptionally regulate gene expression and thereby contribute to the modulation of numerous complex and disease-relevant cellular processes, including cell proliferation, cell motility, apoptosis and stress response. miRNA-31-5p is encoded on a genomic fragile site, 9p21.3, which is reportedly lost in many hepatocellular carcinoma (HCC) tumors. Based on previous findings, we hypothesized that miR-31-5p alters chemosensitivity and that miR-31-5p mimics may influence sensitivity to chemotherapeutics in HCC as well as in a variety of other cancers. METHODS: MiR-31-5p and PARP1 in HCC tissues were tested by RT-PCR and histological analysis, respectively. Next, clonogenic assay and western blot were used to detect miR-31-5p and PARP1 to modulate sensitivity to OXA-based chemotherapy. The distribution of OXA in the nuclear and intracellular was detected by ICP-MS. Coimmunoprecipitation was used to characterize the protein-protein interaction between PARP1 and ABCB9. A xenograft nude mouse model was used to examine the in vivo effects of miR-31-5p. RESULTS: Reintroduction of miR-31-5p into miR-31-5p-null Hep3B cells significantly enhanced clonogenic resistance to oxaliplatin. Although miR-31-5p re-expression increased chemoresistance, it paradoxically increased the relative intracellular accumulation of oxaliplatin. This effect was coupled with a significantly decreased intranuclear concentration of oxaliplatin by ICP-MS. miR-31-5p prevents the nuclear location of PARP1 detected by immunofluorescence, histological analysis and Western blotting analysis. We subsequently identified an indirect miR-31-5p-mediated upregulation of ABCB9, which is a transporter associated with drug accumulation in lysosomes, along with an increased uptake of oxaliplatin to lysosomes; these phenomena were associated with a downregulation of PARP1, a bipotential transcriptional regulator with multiple miR-31-5p binding sites. However, the indirect overexpression of ABCB9 promoted cellular chemosensitivity, suggesting that miR-31-5p promotes chemoresistance largely via an ABCB9-independent mechanism. CONCLUSIONS: Overall, our data suggest that the loss of miR-31-5p from HCC tumors promotes chemosensitivity, and this knowledge may be prognostically beneficial in the context of therapeutic sensitivity.