Widowed status predicts poor overall survival of Chinese patients with prostate cancer.

BACKGROUND: Little is known about the influence of marital status on Chinese prostate cancer (PCa) patients. Marital status may have an impact on overall survival in Chinese men with prostate cancer. METHODS: We identified 4,208 Chinese patients diagnosed with PCa between 2004 and 2015 in the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate Cox proportional hazard models were used to determine the impact of marital status on the overall survival (OS) of Chinese PCa patients. Survival analysis was performed using the Kaplan-Meier method. Smoothing function and threshold effect analysis were performed to determine the turning points of variables. RESULTS: Univariate analysis demonstrated that marital status, prostate-specific antigen (PSA) category, surgery status, T stage, N stage, and M stage were associated with OS. Multivariate analysis further indicated that marital status, PSA category, surgery status, T stage, and M stage were independent risk factors of OS. Survival analysis demonstrated that the nonwidowed group had a better OS than the widowed group. The risk of poor OS increased rapidly with the PSA level up to the turning point 15.6 and 45.4 ng/mL in the nonwidowed group (HR =1.089; 95% CI: 1.064-1.115; P<0.0001) and the widowed group (HR =1.056; 95% CI: 1.028-1.084; P<0.001), respectively. CONCLUSIONS: In conclusion, this study demonstrated that widowed status greatly affects the OS of Chinese PCa patients. Altogether, this study highlights the importance of psychological intervention, especially for widowed Chinese PCa patients. Timely psychological intervention for widowed Chinese PCa patients might improve the survival outcomes of PCa.

[Comprehensive analysis of therapeutic methods and effect on cesarean scar pregnancy].

OBJECTIVE: To evaluate the efficacies and medic economic efficiency of therapeutic method for cesarean scar pregnancy (CSP). METHODS: The pertinent literatures on the treatment of CSP were collected and screened by retrieving some Chinese and English databases, such as PubMed, VIP and Wanfang Data. The weighting means and polled standard deviations of operative duration, operative hemorrhage volume, hysterectomy rate, length of stay, medical fees and the time of serum level of beta-human chorionic gonadotropin (ß-HCG) returning to normal were reckoned. RESULTS: Among different therapeutic methods of CSP, curettage duration was shortest in the patients with methotrexate (MTX) injection; operative hemorrhage volume, hysterectomy rate and length of stay were smallest in those with uterine artery embolization; medical fees was least in those with local MTX injection; the time of serum ß-HCG level returning to normal was shortest in those with hysteroscopic and/or laparoscopic operation after MTX injection or uterine artery embolization. CONCLUSION: Curettage after uterine artery embolization offers multiple advantages over therapeutic methods in the treatment of CSP.

Characterization of a novel splice variant of δ ENaC subunit in human lungs.

Salt absorption via apical epithelial sodium channels (ENaC) is a critical rate-limiting process in maintaining airway and lung lining fluid at the physiological level. δ ENaC (termed δ1 in this article) has been detected in human lung epithelial cells in addition to α, ß, and γ subunits (Ji HL, Su XF, Kedar S, Li J, Barbry P, Smith PR, Matalon S, Benos DJ. J Biol Chem 281: 8233-8241, 2006; Nie HG, Chen L, Han DY, Li J, Song WF, Wei SP, Fang XH, Gu X, Matalon S, Ji HL, J Physiol 587: 2663-2676, 2009) and may contribute to the differences in the biophysical properties of amiloride-inhibitable cation channels in pulmonary epithelial cells. Here we cloned a splicing variant of the δ1 ENaC, namely, δ2 ENaC in human bronchoalveolar epithelial cells (16HBEo). δ2 ENaC possesses 66 extra amino acids attached to the distal amino terminal tail of the δ1 ENaC. δ2 ENaC was expressed in both alveolar type I and II cells of human lungs as revealed by in situ hybridization and real-time RT-PCR. To characterize the biophysical and pharmacological features of the splicing variant, we injected Xenopus oocytes with human ENaC cRNAs and measured whole cell and single channel currents of δ1ßγ, δ2ßγ, and αßγ channels. Oocytes injected with δ2ßγ cRNAs exhibited whole cell currents significantly greater than those expressing δ1ßγ and αßγ channels. Single channel activity, unitary conductance, and open probability of δ2ßγ channels were significantly greater compared with δ1ßγ and αßγ channels. In addition, δ2ßγ and δ1ßγ channels displayed significant differences in apparent Na(+) affinity, dissociation constant for amiloride (K(i)(amil)), the EC(50) for capsazepine activation, and gating kinetics by protons. Channels comprising of this novel splice variant may contribute to the diversities of native epithelial Na(+) channels.

Pulmonary vein sarcoma: a case report.

Recently, we treated a patient with pulmonary vein sarcoma. The patient was a 41-year-old woman, had cough, short of breath and apsychia, with obvious jugular venous distention, rales in both lungs and a diastolic murmur at the apex. CT and Echo revealed a tumor in the left atrium. She received an emergency surgery to remove the mass in the heart. The pathological diagnosis demonstrated it as leiomyosarcoma. Though the patient accepted radiotherapy and chemotherapy, she still died of recurrence and metastasis of the sarcoma 10 months after operation.

8-(4-chlorophenylthio)-guanosine-3',5'-cyclic monophosphate-Na stimulates human alveolar fluid clearance by releasing external Na+ self-inhibition of epithelial Na+ channels.

Salt absorption via alveolar epithelial Na(+) channels (ENaC) is a critical step for maintaining an airspace free of flooding. Previously, we found that 8-(4-chlorophenylthio)-guanosine-3',5'-cyclic monophosphate-Na (CPT-cGMP) activated native and heterologous ENaC. To investigate the potential pharmacological relevance, we applied this compound intratracheally to human lungs and found that ex vivo alveolar fluid clearance was increased significantly. Furthermore, this compound eliminated self-inhibition in human lung H441 cells and in oocytes expressing human αßγ but not δßγ channels. To further elucidate this novel mechanism, we constructed mutants abolishing (ß(ΔV348) and γ(H233R)) or augmenting (α(Y458A) and γ(M432G)) self-inhibition. The mutants eliminating self-inhibition lost their responses to CPT-cGMP, whereas those enhancing self-inhibition facilitated the stimulatory effects of this compound. CPT-cGMP was unable to activate a high P(o) mutant (ß(S520C)) and plasmin proteolytically cleaved channels. Our data suggest that elimination of self-inhibition of αßγ ENaC may be a novel mechanism for CPT-cGMP to stimulate salt reabsorption in human lungs.

Cpt-cAMP activates human epithelial sodium channels via relieving self-inhibition.

External Na(+) self-inhibition is an intrinsic feature of epithelial sodium channels (ENaC). Cpt-cAMP regulates heterologous guinea pig but not rat αßγ ENaC in a ligand-gated manner. We hypothesized that cpt-cAMP may eliminate the self-inhibition of human ENaC thereby open channels. Regulation of self-inhibition by this compound in oocytes was analyzed using the two-electrode voltage clamp and Ussing chamber setups. External cpt-cAMP stimulated human but not rat and murine αßγ ENaC in a dose- and external Na(+) concentration-dependent fashion. Intriguingly, cpt-cAMP activated human δßγ more potently than αßγ channels, suggesting that structural diversity in ectoloop between human α, δ, and those ENaC of other species determines the stimulating effects of cpt-cAMP. Cpt-cAMP increased the ratio of stationary and maximal currents. Mutants having abolished self-inhibition (ß(ΔV348) and γ(H233R)) almost completely eliminated cpt-cAMP mediated activation of ENaC. On the other hand, mutants both enhancing self-inhibition and elevating cpt-cAMP sensitivity increased the stimulating effects of the compound. This compound, however, could not activate already fully opened channels, e.g., degenerin mutation (αß(S520C)γ) and the proteolytically cleaved ENaC by plasmin. Cpt-cAMP activated native ENaC to the same extent as that for heterologous ENaC in human lung epithelial cells. Our data demonstrate that cpt-cAMP, a broadly used PKA activator, stimulates human αßγ and δßγ ENaC channels by relieving self-inhibition.

K+ channel openers restore verapamil-inhibited lung fluid resolution and transepithelial ion transport.

BACKGROUND: Lung epithelial Na+ channels (ENaC) are regulated by cell Ca2+ signal, which may contribute to calcium antagonist-induced noncardiogenic lung edema. Although K+ channel modulators regulate ENaC activity in normal lungs, the therapeutical relevance and the underlying mechanisms have not been completely explored. We hypothesized that K+ channel openers may restore calcium channel blocker-inhibited alveolar fluid clearance (AFC) by up-regulating both apical and basolateral ion transport. METHODS: Verapamil-induced depression of heterologously expressed human alphabetagamma ENaC in Xenopus oocytes, apical and basolateral ion transport in monolayers of human lung epithelial cells (H441), and in vivo alveolar fluid clearance were measured, respectively, using the two-electrode voltage clamp, Ussing chamber, and BSA protein assays. Ca2+ signal in H441 cells was analyzed using Fluo 4AM. RESULTS: The rate of in vivo AFC was reduced significantly (40.6+/-6.3% of control, P<0.05, n=12) in mice intratracheally administrated verapamil. KCa3.1 (1-EBIO) and KATP (minoxidil) channel openers significantly recovered AFC. In addition to short-circuit current (Isc) in intact H441 monolayers, both apical and basolateral Isc levels were reduced by verapamil in permeabilized monolayers. Moreover, verapamil significantly altered Ca2+ signal evoked by ionomycin in H441 cells. Depletion of cytosolic Ca2+ in alphabetagamma ENaC-expressing oocytes completely abolished verapamil-induced inhibition. Intriguingly, KV (pyrithione-Na), K Ca3.1 (1-EBIO), and KATP (minoxidil) channel openers almost completely restored the verapamil-induced decrease in Isc levels by diversely up-regulating apical and basolateral Na+ and K+ transport pathways. CONCLUSIONS: Our observations demonstrate that K+ channel openers are capable of rescuing reduced vectorial Na+ transport across lung epithelial cells with impaired Ca2+ signal.

8-pCPT-cGMP stimulates alphabetagamma-ENaC activity in oocytes as an external ligand requiring specific nucleotide moieties.

Epithelial sodium channels (ENaC) are regulated by protein kinase A, in addition to a broad spectrum of other protein kinases. It is not clear whether cGMP/PKG signaling might regulate ENaC activity. We examined the responses of alphabetagamma-ENaC channels expressed in Xenopus oocytes to 8-(4-chlorophenylthio)-cGMP (8-pCPT-cGMP), a cell-permeable cGMP analog. This compound stimulated human alphabetagamma-ENaC activity in a dose-dependent fashion, but cell-impermeable cGMP had no effect. Similar stimulatory effects of cGMP were observed in oocytes expressing either mouse or rat alphabetagamma-ENaC channels. The identical ion selectivity and amiloride sensitivity of the 8-pCPT-cGMP-activated currents to those of alphabetagamma-ENaC channels suggest that the cGMP-activated currents are associated with expressed ENaC. The PKGI activator Sp isomer of beta-phenyl-1,N(2)-etheno-8-bromo-cGMP did not elicit a rise in ENaC current and that the 8-pCPT-cGMP-induced activation of ENaC channels was blocked by incubating oocytes with a PKG inhibitor, but not with other cGMP-sensitive kinase inactivators for PKA, MEK, MAP, and PKC. Surprisingly, both site-directed mutation of putative consensus PKG phosphorylation sites and truncation of entire cytosolic NH(2)- and COOH-terminal tails did not alter the response to 8-pCPT-cGMP. The ENaC activity was activated to the same extent by 8-pCPT-cGMP in cells in which PKGII expression was knocked down using small interfering RNA. Analog to 8-CPT-cAMP, 8-pCPT-cGMP was capable of activating ENaC in the identical manner in cell-free outside-out patches. We conclude that the rapid upregulation of human alphabetagamma-ENaC activity in oocytes by external 8-pCPT-cGMP and 4-chlorothiolphenol-cAMP depends on the para-chlorophenylthiol and the hydroxy groups, and 8-pCPT-cGMP may serve as a novel ENaC ligand in addition to activating PKG signal.

Expression and regulation of epithelial Na+ channels by nucleotides in pleural mesothelial cells.

Pleural effusions are commonly clinical disorders, resulting from the imbalance between pleural fluid turnover and reabsorption. The mechanisms underlying pleural fluid clearance across the mesothelium remain to be elucidated. We hypothesized that epithelial Na(+) channel (ENaC) is expressed and forms the molecular basis of the amiloride-sensitive resistance in human mesothelial cells. Our RT-PCR results showed that three ENaC subunits, namely, alpha, beta, gamma, and two delta ENaC subunits, are expressed in human primary pleural mesothelial cells, a human mesothelioma cell line (M9K), and mouse pleural tissue. In addition, Western blotting and immunofluorescence microscopy studies revealed that alpha, beta, gamma, and delta ENaC subunits are expressed in primary human mesothelial cells and M9K cells at the protein level. An amiloride-inhibitable short-circuit current was detected in M9K monolayers and mouse pleural tissues when mounted in Ussing chambers. Whole-cell patch clamp recordings showed an ENaC-like channel with an amiloride concentration producing 50% inhibition of 12 microM in M9K cells. This cation channel has a high affinity for extracellular Na+ ions (K(m): 53 mM). The ion selectivity of this channel to cations follows the same order as ENaC: Li+ > Na+ > K+. The unitary Li(+) conductance was 15 pS in on-cell patches. Four ENaC subunits form a functional Na+ channel when coinjected into Xenopus oocytes. Furthermore, we found that both forskolin and cGMP increased the short-circuit currents in mouse pleural tissues. Taken together, our data demonstrate that the ENaC channels are biochemically and functionally expressed in human pleural mesothelial cells, and can be up-regulated by cyclic AMP and cyclic GMP.

SARS-CoV proteins decrease levels and activity of human ENaC via activation of distinct PKC isoforms.

Among the multiple organ disorders caused by the severe acute respiratory syndrome coronavirus (SARS-CoV), acute lung failure following atypical pneumonia is the most serious and often fatal event. We hypothesized that two of the hydrophilic structural coronoviral proteins (S and E) would regulate alveolar fluid clearance by decreasing the cell surface expression and activity of amiloride-sensitive epithelial sodium (Na(+)) channels (ENaC), the rate-limiting protein in transepithelial Na(+) vectorial transport across distal lung epithelial cells. Coexpression of either S or E protein with human alpha-, beta-, and gamma-ENaC in Xenopus oocytes led to significant decreases of both amiloride-sensitive Na(+) currents and gamma-ENaC protein levels at their plasma membranes. S and E proteins decreased the rate of ENaC exocytosis and either had no effect (S) or decreased (E) rates of endocytosis. No direct interactions among SARS-CoV E protein with either alpha- or gamma-ENaC were indentified. Instead, the downregulation of ENaC activity by SARS proteins was partially or completely restored by administration of inhibitors of PKCalpha/beta1 and PKCzeta. Consistent with the whole cell data, expression of S and E proteins decreased ENaC single-channel activity in oocytes, and these effects were partially abrogated by PKCalpha/beta1 inhibitors. Finally, transfection of human airway epithelial (H441) cells with SARS E protein decreased whole cell amiloride-sensitive currents. These findings indicate that lung edema in SARS infection may be due at least in part to activation of PKC by SARS proteins, leading to decreasing levels and activity of ENaC at the apical surfaces of lung epithelial cells.

Delta-subunit confers novel biophysical features to alpha beta gamma-human epithelial sodium channel (ENaC) via a physical interaction.

Native amiloride-sensitive Na+ channels exhibit a variety of biophysical properties, including variable sensitivities to amiloride, different ion selectivities, and diverse unitary conductances. The molecular basis of these differences has not been elucidated. We tested the hypothesis that co-expression of delta-epithelial sodium channel (ENaC) underlies, at least in part, the multiplicity of amiloride-sensitive Na+ conductances in epithelial cells. For example, the delta-subunit may form multimeric channels with alpha beta gamma-ENaC. Reverse transcription-PCR revealed that delta-ENaC is co-expressed with alpha beta gamma-subunits in cultured human lung (H441 and A549), pancreatic (CFPAC), and colonic epithelial cells (Caco-2). Indirect immunofluorescence microscopy revealed that delta-ENaC is co-expressed with alpha-, beta-, and gamma-ENaC in H441 cells at the protein level. Measurement of current-voltage that cation selectivity ratios for the revealed relationships Na+/Li+/K+/Cs+/Ca2+/Mg2+, the apparent dissociation constant (Ki) for amiloride, and unitary conductances for delta alpha beta gamma-ENaC differed from those of both alpha beta gamma- and delta beta gamma-ENaC (n = 6). The contribution of the delta subunit to P(Li)/P(Na) ratio and unitary Na+ conductance under bi-ionic conditions depended on the injected cRNA concentration. In addition, the EC50 for proton activation, mean open and closed times, and the self-inhibition time of delta alpha beta gamma-ENaC differed from those of alpha beta gamma- and delta beta gamma-ENaC. Co-immunoprecipitation of delta-ENaC with alpha- and gamma-subunits in H441 and transfected COS-7 cells suggests an interaction among these proteins. We, therefore, concluded that the interactions of delta-ENaC with other subunits could account for heterogeneity of native epithelial channels.