Functional dissection of parabrachial substrates in processing nociceptive information.

Painful stimuli elicit first-line reflexive defensive reactions and, in many cases, also evoke second-line recuperative behaviors, the latter of which reflects the sensing of tissue damage and the alleviation of suffering. The lateral parabrachial nucleus (lPBN), composed of external- (elPBN), dorsal- (dlPBN), and central/superior-subnuclei (jointly referred to as slPBN), receives sensory inputs from spinal projection neurons and plays important roles in processing affective information from external threats and body integrity disruption. However, the organizational rules of lPBN neurons that provoke diverse behaviors in response to different painful stimuli from cutaneous and deep tissues remain unclear. In this study, we used region-specific neuronal depletion or silencing approaches combined with a battery of behavioral assays to show that slPBN neurons expressing substance P receptor ( NK1R) (lPBN NK1R) are crucial for driving pain-associated self-care behaviors evoked by sustained noxious thermal and mechanical stimuli applied to skin or bone/muscle, while elPBN neurons are dispensable for driving such reactions. Notably, lPBN NK1R neurons are specifically required for forming sustained somatic pain-induced negative teaching signals and aversive memory but are not necessary for fear-learning or escape behaviors elicited by external threats. Lastly, both lPBN NK1R and elPBN neurons contribute to chemical irritant-induced nocifensive reactions. Our results reveal the functional organization of parabrachial substrates that drive distinct behavioral outcomes in response to sustained pain versus external danger under physiological conditions.

Dual specific phosphatase 4 suppresses ferroptosis and enhances sorafenib resistance in hepatocellular carcinoma.

AIMS: This investigation aims to elucidate the mechanism underlying sorafenib-induced ferroptosis in hepatocellular carcinoma (HCC). METHODS: The role of dual specificity phosphatase 4 (DUSP4) in sorafenib-treated HCC was investigated using comprehensive assessments both in vitro and in vivo, including Western blotting, qRT-PCR, cell viability assay, lipid reactive oxygen species (ROS) assay, immunohistochemistry, and xenograft tumor mouse model. Additionally, label-free quantitative proteomics was employed to identify potential proteins associated with DUSP4. RESULTS: Our study revealed that suppression of DUSP4 expression heightens the susceptibility of HCC cells to ferroptosis inducers, specifically sorafenib and erastin, in both in vitro and in vivo settings. Furthermore, we identified DUSP4-mediated regulation of key ferroptosis-related markers, such as ferritin light chain (FTL) and ferritin heavy chain 1 (FTH1). Notably, label-free quantitative proteomics unveiled the phosphorylation of threonine residue T148 on YTH Domain Containing 1 (YTHDC1) by DUSP4. Further investigations unraveled that YTHDC1, functioning as an mRNA nuclear export regulator, is a direct target of DUSP4, orchestrating the subcellular localization of FTL and FTH1 mRNAs. Significantly, our study highlights a strong correlation between elevated DUSP4 expression and sorafenib resistance in HCC. CONCLUSIONS: Our findings introduce DUSP4 as a negative regulator of sorafenib-induced ferroptosis. This discovery opens new avenues for the development of ferroptosis-based therapeutic strategies tailored for HCC treatment.

Ac4C Enhances the Translation Efficiency of Vegfa mRNA and Mediates Central Sensitization in Spinal Dorsal Horn in Neuropathic Pain.

N4-Acetylcytidine (ac4C), a highly conserved post-transcriptional machinery with extensive existence for RNA modification, plays versatile roles in various cellular processes and functions. However, the molecular mechanism by which ac4C modification mediates neuropathic pain remains elusive. Here, it is found that the enhanced ac4C modification promotes the recruitment of polysome in Vegfa mRNA and strengthens the translation efficiency following SNI. Nerve injury increases the expression of NAT10 and the interaction between NAT10 and Vegfa mRNA in the dorsal horn neurons, and the gain and loss of NAT10 function further confirm that NAT10 is involved in the ac4C modification in Vegfa mRNA and pain behavior. Moreover, the ac4C-mediated VEGFA upregulation contributes to the central sensitivity and neuropathic pain induced by SNI or AAV-hSyn-NAT10. Finally, SNI promotes the binding of HNRNPK in Vegfa mRNA and subsequently recruits the NAT10. The enhanced interaction between HNRNPK and NAT10 contributes to the ac4C modification of Vegfa mRNA and neuropathic pain. These findings suggest that the enhanced interaction between HNRNPK and Vegfa mRNA upregulates the ac4C level by recruiting NAT10 and contributes to the central sensitivity and neuropathic pain following SNI. Blocking this cascade may be a novel therapeutic approach in patients with neuropathic pain.

Systolic Blood Pressure and Cardiovascular Risk in Normotensive Adults.

OBJECTIVE: To examine the association of systolic blood pressure (SBP) and cardiovascular risk in normotensive adults. PATIENTS AND METHODS: This study analyzed data from 7 prospective cohorts between September 29, 1948, and December 31, 2018. Complete information on history of hypertension and baseline blood pressure measurements were required for inclusion. We excluded individuals younger than 18 years old, those with a history of hypertension, and patients with baseline SBP measurements of less than 90 mm Hg or 140 mm Hg or higher. Cox proportional hazards regression and restricted cubic spline models were used to evaluate the hazards of cardiovascular outcomes. RESULTS: A total of 31,033 participants were included. The mean ± SD age was 45.3±14.8 years, 16,693 of the participants (53.8%) were female, and the mean ± SD SBP was 115.8±11.7. Over a median follow-up of 23.5 years, 7005 cardiovascular events occurred. Compared with those who had SBP levels of 90 to 99 mm Hg, participants with SBP levels of 100 to 109, 110 to 119, 120 to 129, and 130 to 139 mm Hg experienced 23% (hazard ratio [HR], 1.23; 95% CI, 1.07 to 1.42), 53% (HR, 1.53; 95% CI, 1.33 to 1.76), 87% (HR, 1.87; 95% CI, 1.62 to 2.16), and 117% (HR, 2.17; 95% CI, 1.87 to 2.52) increased risks of cardiovascular events, respectively. Compared with follow-up SBP of 90 to 99 mm Hg, the HRs for cardiovascular events were 1.25 (95% CI, 1.02 to 1.54), 1.93 (95% CI, 1.58 to 2.34), 2.55 (95% CI, 2.09 to 3.10), and 3.39 (95% CI, 2.78 to 4.14), respectively, for follow-up SBP levels of 100 to 109, 110 to 119, 120 to 129, and 130 to 139 mm Hg. CONCLUSION: In adults without hypertension, there is a stepwise increase in risk of cardiovascular events, with increasing SBP starting at levels as low as 90 mm Hg.

Nalbuphine attenuates morphine-induced scratching by inhibiting PKCß-dependent microglial activation and p38 phosphorylation in male mice.

Morphine-induced scratching (MIS) is a common adverse effect associated with the use of morphine as analgesia after surgery. However, the treatment of MIS is less than satisfactory due to its unclear mechanism, which needs to be enunciated. We found that intrathecal (i.t.) injections of morphine significantly enhanced scratching behavior in C57BL/6J male mice as well as increased the expressions of protein kinase C ß (PKCß), phosphorylated p38 mitogen-activated protein kinases (MAPK), and ionized calcium-binding adapter molecule 1 (Iba1) within spinal cord dorsal horn. Conversely, using the kappa opioid receptor antagonist nalbuphine significantly attenuated scratching behavior, reduced PKCß expression and p38 phosphorylation, and decreased spinal dorsal horn microglial activation, while PKCδ and KOR expression elevated. Spinal PKCß silencing mitigated MIS and microglial activation. Still, knockdown of PKCδ reversed the inhibitory effect of nalbuphine on MIS and microglial activation, indicating that PKCδ is indispensable for the antipruritic effects of nalbuphine. In contrast, PKCß is crucial for inducing microglial activation in MIS in male mice. Our findings show a distinct itch cascade of morphine, PKCß/p38MAPK, and microglial activation, but an anti-MIS pathway of nalbuphine, PKCδ/KOR, and neuron activation.

The α2δ-1-NMDA Receptor Complex Is Critically Involved in Neuropathic Pain Development and Gabapentin Therapeutic Actions.

α2δ-1, commonly known as a voltage-activated Ca2+ channel subunit, is a binding site of gabapentinoids used to treat neuropathic pain and epilepsy. However, it is unclear how α2δ-1 contributes to neuropathic pain and gabapentinoid actions. Here, we show that Cacna2d1 overexpression potentiates presynaptic and postsynaptic NMDAR activity of spinal dorsal horn neurons to cause pain hypersensitivity. Conversely, Cacna2d1 knockdown or ablation normalizes synaptic NMDAR activity increased by nerve injury. α2δ-1 forms a heteromeric complex with NMDARs in rodent and human spinal cords. The α2δ-1-NMDAR interaction predominantly occurs through the C terminus of α2δ-1 and promotes surface trafficking and synaptic targeting of NMDARs. Gabapentin or an α2δ-1 C terminus-interfering peptide normalizes NMDAR synaptic targeting and activity increased by nerve injury. Thus, α2δ-1 is an NMDAR-interacting protein that increases NMDAR synaptic delivery in neuropathic pain. Gabapentinoids reduce neuropathic pain by inhibiting forward trafficking of α2δ-1-NMDAR complexes.

Can therapeutic drug monitoring increase the safety of Imatinib in GIST patients?

Imatinib at 400 mg daily is the standard treatment for patients affected with CML and GIST. The intervariability in plasma concentration is very significant. In many reports, a good therapeutic effect is attributed to an adequate concentration of Imatinib. However, few studies have been conducted to investigate the association between plasma concentration and side effects. Besides, no upper concentration limit of Imatinib plasma concentration detection has been established. The correlation of Imatinib trough concentrations (Cmin ) with adverse effects (AEs) was described here. Plasma samples were obtained from patients after 3 months treatment with Imatinib (steady state, n = 122). Liquid chromatography/ tandem mass spectrometry was used to determine the concentration of Imatinib and its metabolite NDI. The incidence of myelosuppression was increased significantly with the increased Imatinib trough plasma concentration. The plasma level of Imatinib and NDI in patients who developed myelosuppression are 1698.3 ± 598.6 ng/mL and 242.1 ng/mL, respectively, which were significantly higher than those in patients who did not (1327.2 ± 623.4 ng/mL, P = 1.75 × 10-4 ; 206.3 ng/mL, P = 0.006). Estimated exposure thresholds of Imatinib and NDI were 1451.6 ng/mL with ROCAUC (95%CI) of 0.693 (0.597-0.789) and 207.1 ng/mL with ROCAUC (95%CI) of 0.646 (0.546-0.745), respectively. Multivariate regression confirmed the correlation of Imatinib Cmin with myelosuppression. Other side effects such as fluid retention and rash were not found to be correlated with Imatinib concentrations. These results suggest that trough concentration of Imatinib should be taken into consideration to increase the safety of Imatinib therapy in GIST patients.

The Prognostic Value of Peripheral Benzodiazepine Receptor in Patients with Esophageal Squamous Cell Carcinoma.

Background: The peripheral benzodiazepine receptor (PBR) has previously been reported as an oncogene in prostate, breast and colorectal cancers, but its prognostic value, biological behavior and function in esophageal squamous cell carcinoma (ESCC) has not been investigated. Methods: qRT-PCR, western blotting and immunohistochemistry (IHC) were used to detect PBR expression in ESCC and matched non-cancerous tissues. Based on all of the significantly independent factors, a nomogram was established to predict the prognosis of ESCC patients. In addition, we performed comprehensive in vitro experiments to study the functions of PBR in cell growth, colony formation, and migration ability, as well as its relationship with epithelial-mesenchymal transition (EMT) related proteins in ESCC cells. Results: The mRNA and protein expression levels of PBR in ESCC were higher than those in adjacent non-tumor esophageal epithelial tissues. The IHC results demonstrated that PBR expression was an independent prognostic factor in ESCC survival, patients with higher PBR expression had a poorer survival than those with low expression, and PBR expression was significantly associated with lymphoid nodal status. Furthermore, a nomogram was established to reliably predict the probability of death in ESCC patients, with a Harrell's c-index of 0.696. In the vitro experiments, knocking down the expression of PBR inhibited proliferation, colony formation and migration of ESCC cells, and regulated EMT-associated proteins (up-regulation of E-cadherin, ZO-1 and ß-catenin and concomitant with down-regulation of Fibronectin and N-cadherin). Conclusions: PBR is an independent prognostic factor in ESCC, and it promotes ESCC progression and metastasis. Basing on PBR expression level, a nomogram is established and performs a well in predicting survival of ESCC patients.

Presynaptic mGluR5 receptor controls glutamatergic input through protein kinase C-NMDA receptors in paclitaxel-induced neuropathic pain.

Chemotherapeutic drugs such as paclitaxel cause painful peripheral neuropathy in many cancer patients and survivors. Although NMDA receptors (NMDARs) at primary afferent terminals are known to be critically involved in chemotherapy-induced chronic pain, the upstream signaling mechanism that leads to presynaptic NMDAR activation is unclear. Group I metabotropic glutamate receptors (mGluRs) play a role in synaptic plasticity and NMDAR regulation. Here we report that the Group I mGluR agonist (S)-3,5-dihydroxyphenylglycine (DHPG) significantly increased the frequency of miniature excitatory postsynaptic currents (EPSCs) and the amplitude of monosynaptic EPSCs evoked from the dorsal root. DHPG also reduced the paired-pulse ratio of evoked EPSCs in spinal dorsal horn neurons. These effects were blocked by the selective mGluR5 antagonist 2-methyl-6-(phenylethynyl)-pyridine (MPEP), but not by an mGluR1 antagonist. MPEP normalized the frequency of miniature EPSCs and the amplitude of evoked EPSCs in paclitaxel-treated rats but had no effect in vehicle-treated rats. Furthermore, mGluR5 protein levels in the dorsal root ganglion and spinal cord synaptosomes were significantly higher in paclitaxel- than in vehicle-treated rats. Inhibiting protein kinase C (PKC) or blocking NMDARs abolished DHPG-induced increases in the miniature EPSC frequency of spinal dorsal horn neurons in vehicle- and paclitaxel-treated rats. Moreover, intrathecal administration of MPEP reversed pain hypersensitivity caused by paclitaxel treatment. Our findings suggest that paclitaxel-induced painful neuropathy is associated with increased presynaptic mGluR5 activity at the spinal cord level, which serves as upstream signaling for PKC-mediated tonic activation of NMDARs. mGluR5 is therefore a promising target for reducing chemotherapy-induced neuropathic pain.

Bortezomib induces neuropathic pain through protein kinase C-mediated activation of presynaptic NMDA receptors in the spinal cord.

Chemotherapeutic drugs, including bortezomib, often cause painful peripheral neuropathy, which is a severe dose-limiting adverse effect experienced by many cancer patients. The glutamate N-methyl-d-aspartate receptors (NMDARs) at the spinal cord level are critically involved in the synaptic plasticity associated with neuropathic pain. In this study, we determined whether treatment with bortezomib, a proteasome inhibitor, affects the NMDAR activity of spinal dorsal horn neurons. Systemic treatment with bortezomib in rats did not significantly affect postsynaptic NMDAR currents elicited by puff application of NMDA directly to dorsal horn neurons. Bortezomib treatment markedly increased the baseline frequency of miniature excitatory postsynaptic currents (EPSCs), which was completely normalized by the NMDAR antagonist 2-amino-5-phosphonopentanoic acid (AP5). AP5 also reduced the amplitude of monosynaptic EPSCs evoked by dorsal root stimulation in bortezomib-treated, but not vehicle-treated, rats. Furthermore, inhibition of protein kinase C (PKC) with chelerythrine fully reversed the increased frequency of miniature EPSCs and the amplitude of evoked EPSCs in bortezomib-treated rats. Intrathecal injection of AP5 and chelerythrine both profoundly attenuated mechanical allodynia and hyperalgesia induced by systemic treatment with bortezomib. In addition, treatment with bortezomib induced striking membrane translocation of PKC-ßII, PKC-δ, and PKC-ε in the dorsal root ganglion. Our findings indicate that bortezomib treatment potentiates nociceptive input from primary afferent nerves via PKC-mediated tonic activation of presynaptic NMDARs. Targeting presynaptic NMDARs and PKC at the spinal cord level may be an effective strategy for treating chemotherapy-induced neuropathic pain.

Old age at diagnosis increases risk of tumor progression in nasopharyngeal cancer.

Age at diagnosis has been found to be a prognostic factor of outcomes in various cancers. However, the effect of age at diagnosis on nasopharyngeal cancer (NPC) progression has not been explored. We retrospectively evaluated the relationship between age and disease progression in 3,153 NPC patients who underwent radiotherapy, chemotherapy, or chemoradiotherapy between 2007 and 2009. Patients were randomly assigned to either a testing cohort or a validation cohort by computer-generated random assignment. X-tile plots determined the optimal cut-point of age based on survival status to be ≤61 vs. >61 years. Further correlation analysis showed that age >61 years was significantly correlated with the tumor progression and therapeutic regimen in both testing and validation cohorts (P <0.05). In the present study, we observed that older age (>61 years) was a strong and independent predictor of poor disease-free survival (DFS) and cancer-specific survival (CSS), in both univariate and multivariate analyses. Age was also found to be a significant prognostic predictor as well (P <0.05) when evaluating patients with the same disease stage. ROC analysis confirmed the predictive value of age on NPC-specific survival in both cohorts (P <0.001) and suggested that age may improve the ability to discriminate outcomes in NPCs, especially regarding tumor progression. In conclusion, our study suggests that older age at NPC diagnosis is associated with a higher incidence of tumor progression and cancer-specific mortality. Age is a strong and independent predictor of poor outcomes and may allow for more tailored therapeutic decision-making and individualized patient counseling.

Presynaptic N-Methyl-d-aspartate (NMDA) Receptor Activity Is Increased Through Protein Kinase C in Paclitaxel-induced Neuropathic Pain.

Painful peripheral neuropathy is a severe adverse effect of chemotherapeutic drugs such as paclitaxel (Taxol). The glutamate N-methyl-d-aspartate receptors (NMDARs) are critically involved in the synaptic plasticity associated with neuropathic pain. However, paclitaxel treatment does not alter the postsynaptic NMDAR activity of spinal dorsal horn neurons. In this study, we determined whether paclitaxel affects presynaptic NMDAR activity by recording excitatory postsynaptic currents (EPSCs) of dorsal horn neurons in spinal cord slices. In paclitaxel-treated rats, the baseline frequency of miniature EPSCs (mEPSCs) was significantly increased; the NMDAR antagonist 2-amino-5-phosphonopentanoic acid (AP5) completely normalized this frequency. Also, AP5 significantly reduced the amplitude of monosynaptic EPSCs evoked by dorsal root stimulation and reversed the reduction in the paired-pulse ratio of evoked EPSCs in paclitaxel-treated rats. Blocking GluN2A-containing, but not GluN2B-containing, NMDARs largely decreased the frequency of mEPSCs and the amplitude of evoked EPSCs of dorsal horn neurons in paclitaxel-treated rats. Furthermore, inhibition of protein kinase C fully reversed the increased frequency of mEPSCs and the amplitude of evoked EPSCs in paclitaxel-treated rats. Paclitaxel treatment significantly increased the protein level of GluN2A and phosphorylated GluN1 in the dorsal root ganglion. In addition, intrathecal injection of AP5 or systemic administration of memantine profoundly attenuated pain hypersensitivity induced by paclitaxel. Our findings indicate that paclitaxel treatment induces tonic activation of presynaptic NMDARs in the spinal cord through protein kinase C to potentiate nociceptive input from primary afferent nerves. Targeting presynaptic NMDARs at the spinal cord level may be an effective strategy for treating chemotherapy-induced neuropathic pain.

Chloride Homeostasis Critically Regulates Synaptic NMDA Receptor Activity in Neuropathic Pain.

Chronic neuropathic pain is a debilitating condition that remains difficult to treat. Diminished synaptic inhibition by GABA and glycine and increased NMDA receptor (NMDAR) activity in the spinal dorsal horn are key mechanisms underlying neuropathic pain. However, the reciprocal relationship between synaptic inhibition and excitation in neuropathic pain is unclear. Here, we show that intrathecal delivery of K(+)-Cl(-) cotransporter-2 (KCC2) using lentiviral vectors produces a complete and long-lasting reversal of pain hypersensitivity induced by nerve injury. KCC2 gene transfer restores Cl(-) homeostasis disrupted by nerve injury in both spinal dorsal horn and primary sensory neurons. Remarkably, restoring Cl(-) homeostasis normalizes both presynaptic and postsynaptic NMDAR activity increased by nerve injury in the spinal dorsal horn. Our findings indicate that nerve injury recruits NMDAR-mediated signaling pathways through the disruption of Cl(-) homeostasis in spinal dorsal horn and primary sensory neurons. Lentiviral vector-mediated KCC2 expression is a promising gene therapy for the treatment of neuropathic pain.

Fentanyl Enhances Hepatotoxicity of Paclitaxel via Inhibition of CYP3A4 and ABCB1 Transport Activity in Mice.

Fentanyl, a potent opioid analgesic that is used to treat cancer pain, is commonly administered with paclitaxel in advanced tumors. However, the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanism of action is not well studied. The purpose of this study was to investigate the effect of fentanyl on the hepatotoxicity of paclitaxel and its potential mechanisms of action. Pharmacokinetic parameters of paclitaxel were tested using reversed phase high-performance liquid chromatography (RP-HPLC). Aspartate transaminase (AST), alanine aminotransferase (ALT), and mouse liver histopathology were examined. Moreover, the cytotoxicity of anti-carcinogens was examined using 1-(4, 5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT), and the intracellular accumulation of doxorubicin and rhodamine 123 was detected by flow cytometry. Furthermore, the expression of ABCB1 and the activity of ABCB1 ATPase and CYP3A4 were also examined. In this study, the co-administration of fentanyl and paclitaxel prolonged the half-life (t1/2) of paclitaxel from 1.455 hours to 2.344 hours and decreased the clearance (CL) from 10.997 ml/h to 7.014 ml/h in mice. Fentanyl significantly increased the levels of ALT in mice to 88.2 U/L, which is more than 2-fold higher than the level detected in the control group, and it increased the histological damage in mouse livers. Furthermore, fentanyl enhanced the cytotoxicity of anti-carcinogens that are ABCB1 substrates and increased the accumulation of doxorubicin and rhodamine 123. Additionally, fentanyl stimulated ABCB1 ATPase activity and inhibited CYP3A4 activity in the liver microsomes of mice. Our study indicates that the obvious hepatotoxicity during this co-administration was due to the inhibition of CYP3A4 activity and ABCB1 transport activity. These findings suggested that the accumulation-induced hepatotoxicity of paclitaxel when it is combined with fentanyl should be avoided.

Prognostic value of SATB2 expression in patients with esophageal squamous cell carcinoma.

SATB2, a member of the family of special AT-rich binding proteins, has been shown to affect numerous tumorigenesis. However, the role of SATB2 in esophageal squamous cell carcinoma (ESCC) remains unclear. In this study, the SATB2 expression was examined at mRNA and protein levels by quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR), Western blotting, and immunohistochemistry in ESCC tissues and adjacent non-cancerous tissues. Statistical analyses were applied to test the associations between SATB2 expression, clinicopathologic factors, and prognosis. Western blotting and qRT-PCR showed that the expression levels of SATB2 mRNA and protein were both significantly lower in SATB2 tissues than those in non-cancerous tissues. Immunohistochemistry analysis showed that SATB2 expression was significantly correlated with clinical stage and Histological differentiation. The results of Kaplan-Meier analysis indicated that a low expression level of SATB2 resulted in a significantly poor prognosis of ESCC patients. Importantly, multivariate analysis showed that low SATB2 expression was an independent prognostic factor for ESCC patients. In sum, our data suggest that SATB2 plays an important role in ESCC progression, and that decreased expression of SATB2 in tumor tissues could be used as a potential prognostic marker for patients with ESCC.

The prognostic effect of perineural invasion in esophageal squamous cell carcinoma.

BACKGROUND: Perineural invasion (PNI) is correlated with adverse survival in several malignancies, but its significance in esophageal squamous cell carcinoma (ESCC) remains to be clearly defined. The objective of this study was to determine the association between PNI status and clinical outcomes. METHODS: We retrospectively evaluated the PNI of 433 patients with ESCC treated with surgery between 2000 and 2007 at a single academic center. The resulting data were analyzed using Spearman's rank correlation, the Kaplan-Meier method, Cox proportional hazards regression modeling and Harrell's concordance index (C-index). RESULTS: PNI was identified in 209 of the 433 (47.7%) cases of ESCC. The correlation analysis demonstrated that PNI in ESCC was significantly correlated with tumor differentiation, infiltration depth, pN classification and stage (P < 0.05). The five-year overall survival rate was 0.570 for PNI-negative tumors versus 0.326 for PNI-positive tumors. Patients with PNI-negative tumors exhibited a 1.7-fold increase in five-year recurrence-free survival compared with patients with PNI-positive tumors (0.531 v 0.305, respectively; P < 0.0001). In the subset of patients with node-negative disease, PNI was evaluated as a prognostic predictor as well (P < 0.05). In the multivariate analysis, PNI was an independent prognostic factor for overall survival (P = 0.027). The C-index estimate for the combined model (PNI, gender and pN status) was a significant improvement on the C-index estimate of the clinicopathologic model alone (0.739 v 0.706, respectively). CONCLUSIONS: PNI can function as an independent prognostic factor of outcomes in ESCC patients, and the PNI status in primary ESCC specimens should be considered for therapy stratification.

Saracatinib (AZD0530) is a potent modulator of ABCB1-mediated multidrug resistance in vitro and in vivo.

Saracatinib, a highly selective, dual Src/Abl kinase inhibitor, is currently in a Phase II clinical trial for the treatment of ovarian cancer. In our study, we investigated the effect of saracatinib on the reversal of multidrug resistance (MDR) induced by ATP-binding cassette (ABC) transporters in vitro and in vivo. Our results showed that saracatinib significantly enhanced the cytotoxicity of ABCB1 substrate drugs in ABCB1 overexpressing HeLa/v200, MCF-7/adr and HEK293/ABCB1 cells, an effect that was stronger than that of gefitinib, whereas it had no effect on the cytotoxicity of the substrates in ABCC1 overexpressing HL-60/adr cells and its parental sensitive cells. Additionally, saracatinib significantly increased the doxorubicin (Dox) and Rho 123 accumulation in HeLa/v200 and MCF-7/adr cells, whereas it had no effect on HeLa and MCF-7 cells. Furthermore, saracatinib stimulated the ATPase activity and inhibited photolabeling of ABCB1 with [(125)I]-iodoarylazidoprazosin in a concentration-dependent manner. In addition, the homology modeling predicted the binding conformation of saracatinib within the large hydrophobic drug-binding cavity of human ABCB1. However, neither the expression level of ABCB1 nor the phosphorylation level of Akt was altered at the reversal concentrations of saracatinib. Importantly, saracatinib significantly enhanced the effect of paclitaxel against ABCB1-overexpressing HeLa/v200 cancer cell xenografts in nude mice. In conclusion, saracatinib reverses ABCB1-mediated MDR in vitro and in vivo by directly inhibiting ABCB1 transport function, without altering ABCB1 expression or AKT phosphorylation. These findings may be helpful to attenuate the effect of MDR by combining saracatinib with other chemotherapeutic drugs in the clinic.

Effect of dicycloplatin, a novel platinum chemotherapeutical drug, on inhibiting cell growth and inducing cell apoptosis.

Dicycloplatin, a new supramolecular platinum-based antitumor drug, has been approved by the State Food and Administration (SFDA) of China. In this study, we investigated the anticancer activity of dicycloplatin in cancer cells and signaling pathways involved in dicycloplatin-induced apoptosis. Dicycloplatin inhibited the proliferation of cancer cells and increased the percentage of apoptosis in a concentration-dependent manner. Besides, some apoptosis related events were observed after treatment with dicycloplatin, including increase of reactive oxygen species (ROS), collapse of mitochondrial membrane potential (Δψm), release of cytochrome c from the mitochondria to the cytosol, upregulation of p53, which were accompanied by activation of caspase-9, caspase-3, caspase-8, and poly (ADP-ribose) polymerase cleavage in a concentration-dependent manner. The role of apoptosis in dicycloplatin-mediated cell death was further confirmed by the concomitant treatment with caspase-8 or caspase-9 inhibitors, which inhibited apoptosis and PARP cleavage. Intracellular glutathione (GSH) was also found to inhibit the cytotoxic effect of dicycloplatin. In conclusion, these findings suggest that dicycloplatin induces apoptosis through ROS stress-mediated death receptor pathway and mitochondrial pathway which is similar to carboplatin.