Design, synthesis and evaluation of oxime-functionalized nitrofuranylamides as novel antitubercular agents.

A series of oxime-functionalized nitrofuranylamides were designed, synthesized and evaluated for their in vitro anti-mycobacterial activities against MTB H37Rv and drug-resistant clinical isolates. Among them, two compounds 7a and 7b exhibited excellent activity against the three tested strains. Both of them were comparable to the first-line anti-TB agents INH and RIF against MTB H37Rv, and were far more potent than INH and RIF against MDR-TB 16833 and 16995 strains. Thus, both of them could act as leads for further optimization.

Effects of siRNA targeting BMPR-II on the biological activities of human liver cancer cells and its mechanism.

BACKGROUND: Bone morphogenetic protein receptor II (BMPR-II) plays an important role in tumor's invasion and proliferation. In this study, we observed the effects of small interfering RNA (siRNA) targeting bone morphogenetic protein receptor II (BMPR-II) on the biological activities of human liver cells and explore its mechanism. METHODS: The molecular sequences of three siRNA targeting BMPR-IIwere designed and synthesized. In this study, there were 6 groups including group I (normal control), group II (blank control), group III (negative control) and group IV-VI (BMPR-II-siRNA-a, siRNA-b and siRNA-c-transfected cells, respectively). The levels of mRNA and protein of BMPR-II were determined to select the best sequence for BMPR-II silence. After liver cancer cells were transfected with the best sequence, proliferation and invasion of transfected cells were assessed, and apoptosis and cell cycle were detected. The expressions of mitogen-activated protein kinases (MAPKs) signal pathway-related VEGF-C protein were observed after BMPR-II silence and BMPR-II silence combined with inhibiting MAPKs signal pathway, respectively. RESULTS: RT-PCR and Western blot indicated that BMPR-II expression was the highest in HepG2 among the three liver cancer lines (P < 0.01) and the lowest in group IV among the six groups (P < 0.01). MTT assay and transwell assay revealed that the numbers of cell growth and cell transmembrane were significantly lower in group IV than in control groups 48 h after cells were transfected (P < 0.05). Flow cytometer showed that apoptosis was the highest and cells were significantly blocked in S phase 48 h after cells were transfected in group IV (P < 0.01). Western blot indicated that the protein levels of p-P38 (P < 0.01) and vascular endothelial growth factor-C (VEGF-C) (P < 0.01) were significantly decreased after BMPR-II silence. The protein level of VEGF-C was significantly decreased in PD98059 + siRNA-BMPR-II-a and SB203580 + siRNA-BMPR-II-a groups (P < 0.01), especially in SB203580 + siRNA-BMPR-II-a group (P < 0.01). CONCLUSIONS: siRNA targeting BMPR-IIcan markedly inhibit HepG2 proliferation and invasion, promote apoptosis and block HepG2 in S phase. Its mechanism may be that BMPR-II silence down-regulates VEGF-C expression through MAPK/P38 and MAPK/ERK1/2 pathways, especially MAPK/P38. This study provides a new targeted therapy for liver cancer.

Analysis of the impact of platinum-based combination chemotherapy in small cell cervical carcinoma: a multicenter retrospective study in Chinese patients.

BACKGROUND: Small cell cervical carcinoma (SCCC) is a rare, aggressive tumor with a poor prognosis. However, information in relation to its treatment is scarce due to the limited numbers of patients. The aim of this study was to establish whether platinum-based combination chemotherapy may by beneficial in this patient population. METHODS: We carried out a multicenter, retrospective study comprising of 72 Chinese patients with SCCC. The patients were treated between 1995 and 2010 at Sun Yat-sen Memorial Hospital or the Cancer Center of Sun Yat-Sen University, and at the First Affiliated Hospital of Shantou University Medical College, China. RESULTS: Of the 72 patients, 46/72 (63.9%) had Federation of Gynecology and Obstetrics (FIGO) stage Ia-Ib2 and 26/72 (36.1%) had stage IIa-IV disease. Surgery was performed in 63/72 (87.5%) patients, 61/72 (84.7%) patients received chemoradiotherapy and 35/72 (48.6%) received radiotherapy. The 3-year overall survival (OS) and disease-free survival (DFS) rates were as follows: Ia (100%, 100%); Ib1 (62%, 57%); Ib2 (53%, 48%); IIa (36%, 23%); IIb (29%, 21%); IIIb (50%, 50%); and IV (0%, 0%), respectively. The estimated 3-year OS and DFS rates in patients who received platinum-based combination chemotherapy (etoposide + cisplatin [EP], or paclitaxel + cisplatin [TP]) as part of their adjuvant treatment were 64.8% and 63.0%, respectively, compared to 25.2% and 22.0% in those who did not (P = 0.0003; P = 0.0003). Univariate analysis showed that platinum-based combination chemotherapy was associated with improved survival compared to other chemotherapy techniques or no chemotherapy (OS: HR = 0.227; 95% CI, 0.099-0.524; P = 0.001; DFS: HR = 0.210; 95% CI, 0.087-0.506; P = 0.001). Multivariate analysis identified FIGO stage, lymphatic metastasis and platinum-based combination chemotherapy as independent prognostic factors for improved survival in patients with SCCC. CONCLUSIONS: Platinum-based combination chemotherapy (with EP or TP) can improve the 3-year survival outcomes in patients with SCCC. Therefore, it should be considered an important component in a future standardized treatment strategy for SCCC.

Low expression of long noncoding XLOC_010588 indicates a poor prognosis and promotes proliferation through upregulation of c-Myc in cervical cancer.

OBJECTIVE: The identification and investigation of cancer-associated long non-coding RNAs are important for understanding the molecular biology of cancer. The aim of the present study was to examine the expression pattern of lncRNA XLOC_010588 in cervical cancer and to evaluate its biological role and clinical significance in tumor progression. METHODS: We examined the expression of XLOC_010588 in 218 cervical cancer tissues and matched 218 adjacent normal tissues using real-time qRT-PCR. Over-expression and RNA interference approaches were used to investigate the biological functions of XLOC_010588. The effect of XLOC_010588 on proliferation was evaluated by MTT and BrdU assays. Western blot assays were used to investigate the molecular mechanism by which XLOC_010588 increases cervical cancer cell proliferation. RESULTS: The results showed that XLOC_010588 expression in cervical cancer was significantly downregulated. Decreased XLOC_010588 expression was correlated with FIGO stage, tumor size and SCC-Ag. Moreover, cervical cancer patients with XLOC_010588 lower expression have shown poorer prognosis. Multivariate Cox regression analyses showed that XLOC_010588 expression served as an independent predictor for overall survival. Ectopic expression of XLOC_010588 inhibited the proliferation of HeLa and SiHa cells. By contrast, knockdown of XLOC_010588 promoted the growth of HCC94 cells. Western blot assays confirmed that XLOC_010588 physically associates with c-Myc, consequently decreasing the expression of c-Myc. The expression of XLOC_010588 and c-Myc is strongly correlated in cervical cancer tissues. CONCLUSION: These results suggested that XLOC_010588 plays a pivotal role in cervical cancer cell proliferation via decreasing c-Myc expression and implicated the potential application of XLOC_010588 in cervical cancer therapy.

Overexpression of long noncoding RNA HOTAIR predicts a poor prognosis in patients with cervical cancer.

PURPOSE: The long noncoding RNA HOTAIR has been reported to be a good biomarker for poor prognosis in a variety of human cancers. However, whether HOTAIR could serve as novel biomarker to predict prognosis in cervical cancer or not is unknown. The aim of the present study was to examine the expression of HOTAIR in cervical cancers and to investigate the relationship between this lncRNA expression levels and existing clinicopathological factors and patient survival. METHODS: We examined the expression of HOTAIR in 218 cervical cancer tissues and matched 218 adjacent normal tissues using quantitative real-time RT-PCR and analyzed its correlation with the clinical parameters. RESULTS: The results showed that HOTAIR expression in cervical cancer tissues was significantly upregulated compared with the matched nontumorous tissues (P < 0.0001). Increased HOTAIR expression was significantly correlated with FIGO stage (P < 0.0001), lymph node metastasis (P < 0.0001), depth of cervical invasion (P < 0.0001), tumor size (P = 0.006) and age (P = 0.020), but not other clinical characteristics. Moreover, cervical cancer patients with HOTAIR higher expression have shown significantly poorer overall survival (P < 0.0001) and disease-free survival (P < 0.0001) than those with lower HOTAIR expression. Univariate (P < 0.0001, HR = 4.566, 95 % CI 2.122-9.825) and multivariate (P = 0.012, HR = 2.863, 95 % CI 1.263-76.490). Cox regression analyses showed that HOTAIR expression served as an independent predictor for overall survival. CONCLUSIONS: our data indicate that high expression of HOTAIR is involved in cervical cancer progression and could be a potential target for diagnosis and gene therapy.

Immune checkpoint inhibitors and anti-vascular endothelial growth factor antibody/tyrosine kinase inhibitors with or without transarterial chemoembolization as first-line treatment for advanced hepatocellular carcinoma (CHANCE2201): a target trial emulation study.

Background: The role of transarterial chemoembolization (TACE) in the treatment of advanced hepatocellular carcinoma (HCC) is unconfirmed. This study aimed to assess the efficacy and safety of immune checkpoint inhibitors (ICIs) plus anti-vascular endothelial growth factor (anti-VEGF) antibody/tyrosine kinase inhibitors (TKIs) with or without TACE as first-line treatment for advanced HCC. Methods: This nationwide, multicenter, retrospective cohort study included advanced HCC patients receiving either TACE with ICIs plus anti-VEGF antibody/TKIs (TACE-ICI-VEGF) or only ICIs plus anti-VEGF antibody/TKIs (ICI-VEGF) from January 2018 to December 2022. The study design followed the target trial emulation framework with stabilized inverse probability of treatment weighting (sIPTW) to minimize biases. The primary outcome was overall survival (OS). Secondary outcomes included progression-free survival (PFS), objective response rate (ORR), and safety. The study is registered with ClinicalTrials.gov, NCT05332821. Findings: Among 1244 patients included in the analysis, 802 (64.5%) patients received TACE-ICI-VEGF treatment, and 442 (35.5%) patients received ICI-VEGF treatment. The median follow-up time was 21.1 months and 20.6 months, respectively. Post-application of sIPTW, baseline characteristics were well-balanced between the two groups. TACE-ICI-VEGF group exhibited a significantly improved median OS (22.6 months [95% CI: 21.2-23.9] vs 15.9 months [14.9-17.8]; P < 0.0001; adjusted hazard ratio [aHR] 0.63 [95% CI: 0.53-0.75]). Median PFS was also longer in TACE-ICI-VEGF group (9.9 months [9.1-10.6] vs 7.4 months [6.7-8.5]; P < 0.0001; aHR 0.74 [0.65-0.85]) per Response Evaluation Criteria in Solid Tumours (RECIST) version 1.1. A higher ORR was observed in TACE-ICI-VEGF group, by either RECIST v1.1 or modified RECIST (41.2% vs 22.9%, P < 0.0001; 47.3% vs 29.7%, P < 0.0001). Grade ≥3 adverse events occurred in 178 patients (22.2%) in TACE-ICI-VEGF group and 80 patients (18.1%) in ICI-VEGF group. Interpretation: This multicenter study supports the use of TACE combined with ICIs and anti-VEGF antibody/TKIs as first-line treatment for advanced HCC, demonstrating an acceptable safety profile. Funding: National Natural Science Foundation of China, National Key Research and Development Program of China, Jiangsu Provincial Medical Innovation Center, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, and Nanjing Life Health Science and Technology Project.

Transarterial chemoembolization with PD-(L)1 inhibitors plus molecular targeted therapies for hepatocellular carcinoma (CHANCE001).

There is considerable potential for integrating transarterial chemoembolization (TACE), programmed death-(ligand)1 (PD-[L]1) inhibitors, and molecular targeted treatments (MTT) in hepatocellular carcinoma (HCC). It is necessary to investigate the therapeutic efficacy and safety of TACE combined with PD-(L)1 inhibitors and MTT in real-world situations. In this nationwide, retrospective, cohort study, 826 HCC patients receiving either TACE plus PD-(L)1 blockades and MTT (combination group, n = 376) or TACE monotherapy (monotherapy group, n = 450) were included from January 2018 to May 2021. The primary endpoint was progression-free survival (PFS) according to modified RECIST. The secondary outcomes included overall survival (OS), objective response rate (ORR), and safety. We performed propensity score matching approaches to reduce bias between two groups. After matching, 228 pairs were included with a predominantly advanced disease population. Median PFS in combination group was 9.5 months (95% confidence interval [CI], 8.4-11.0) versus 8.0 months (95% CI, 6.6-9.5) (adjusted hazard ratio [HR], 0.70, P = 0.002). OS and ORR were also significantly higher in combination group (median OS, 19.2 [16.1-27.3] vs. 15.7 months [13.0-20.2]; adjusted HR, 0.63, P = 0.001; ORR, 60.1% vs. 32.0%; P < 0.001). Grade 3/4 adverse events were observed at a rate of 15.8% and 7.5% in combination and monotherapy groups, respectively. Our results suggest that TACE plus PD-(L)1 blockades and MTT could significantly improve PFS, OS, and ORR versus TACE monotherapy for Chinese patients with predominantly advanced HCC in real-world practice, with an acceptable safety profile.

Retraction Notice to: Silencing Long Non-coding RNA LINC01224 Inhibits Hepatocellular Carcinoma Progression via MicroRNA-330-5p-Induced Inhibition of CHEK1.

[This retracts the article DOI: 10.1016/j.omtn.2019.10.007.].

[Study on the conversion of acrylic C=C double bonds during dark reaction after UV curing using infrared spectroscopy].

Infrared spectroscopy was used to determine 1,648-1,589 cm(-1) characteristic absorption peak area so as to study the conversation of acrylic C=C double bonds after UV curing. The effects of phototinitiators, active diluents and UV curing resins on the conversion of C=C double bonds were also investigated. The results showed that 40%-85% of C=C double bonds were conversed during dark reaction after 45 s UV curing. Dark reaction will be changed gently after 1.75 h, but 95% conversion of C=C double bonds needed more than 24 h. The rates of polymerization and conversation were affected by photoinitiators, the concentration of photoinitiator, oxygen inhibition, and C=C functional groups of active diluents. The rate of polymerization was affected by the C=C functional groups and types of UV curing resins, but conversation was not.

Design, synthesis, and biological evaluation of ligustrazine/resveratrol hybrids as potential anti-ischemic stroke agents.

To search for potent anti-ischemic stroke agents, a series of tetramethylpyrazine (TMP)/resveratrol (RES) hybrids 6a-t were designed and synthesized. These hybrids inhibited adenosine diphosphate (ADP)- or arachidonic acid (AA)-induced platelet aggregation, among them, 6d, 6g-i, 6o and 6q were more active than TMP. The most active compound 6h exhibited more potent anti-platelet aggregation activity than TMP, RES, as well as positive control ticlopidine (Ticlid) and aspirin (ASP). Furthermore, 6h exerted strong antioxidative activity in a dose-dependent manner in rat pheochromocytoma PC12 cells which were treated with hydrogen peroxide (H2O2) or hydroxyl radical (·OH). Importantly, 6h significantly protected primary neuronal cells suffered from oxygen-glucose deprivation/reoxygenation (OGD/R) injury, comparable to an anti-ischemic drug edaravone (Eda). Together, our findings suggest that 6h may be a promising candidate warranting further investigation for the intervention of ischemic stroke.

Nitric oxide donating anti-glaucoma drugs: advances and prospects.

Glaucoma is a disease that causes irreversible blindness. Reducing intraocular pressure (IOP) is the main treatment at present. Nitric oxide (NO), an endogenous gas signaling molecule, can increase aqueous humor outflow facility, inhibit aqueous humor production thereby reducing IOP, as well as regulate eye blood flow and protect the optic nerve. Therefore, NO donating anti-glaucoma drugs have broad research prospects. In this review, we summarize NO-mediated therapy for glaucoma, and the state of the art of some NO donating molecules, including latanoprostene bunod in market and some other candidate compounds, for the intervention of glaucoma, as well as prospects and challenges ahead in this field.

Silencing Long Non-coding RNA LINC01224 Inhibits Hepatocellular Carcinoma Progression via MicroRNA-330-5p-Induced Inhibition of CHEK1.

Hepatocellular carcinoma (HCC) accounts for approximately 85%-90% of primary liver cancers. Based on in silico analysis, differentially expressed long non-coding RNA (lncRNA) LINC01224 in HCC, the downstream microRNA (miRNA) miR-330-5p, and its target gene checkpoint kinase 1 (CHEK1) were selected as research subjects. Herein, this study was designed to evaluate their interaction effects on the malignant phenotypes of HCC cells. LINC01224 and CHEK1 were upregulated and miR-330-5p was downregulated in HCC cells. miR-330-5p shared negative correlations with LINC01224 and CHEK1, and LINC01224 shared a positive correlation with CHEK1. Notably, LINC01224 could specifically bind to miR-330-5p, and CHEK1 was identified as a target gene of miR-330-5p. When LINC01224 was silenced or miR-330-5p was elevated, the sphere and colony formation abilities and proliferative, migrative, and invasive potentials of HCC cells were diminished, while cell cycle arrest and apoptosis were enhanced. Moreover, LINC01224 induced HCC progression in vitro and accelerated tumor formation in nude mice by increasing CHEK1 expression. The key findings of the present study demonstrated that silencing LINC01224 could downregulate the expression of CHEK1 by competitively binding to miR-330-5p, thus inhibiting HCC progression. This result highlights the LINC01224/miR-330-5p/CHEK1 axis as a novel molecular mechanism involved in the pathology of HCC.

Validation and evaluation of clinical prediction systems for first and repeated transarterial chemoembolization in unresectable hepatocellular carcinoma: A Chinese multicenter retrospective study.

BACKGROUND: The treatment outcome of transarterial chemoembolization (TACE) in unresectable hepatocellular carcinoma (HCC) varies greatly due to the clinical heterogeneity of the patients. Therefore, several prognostic systems have been proposed for risk stratification and candidate identification for first TACE and repeated TACE (re-TACE). AIM: To investigate the correlations between prognostic systems and radiological response, compare the predictive abilities, and integrate them in sequence for outcome prediction. METHODS: This nationwide multicenter retrospective cohort consisted of 1107 unresectable HCC patients in 15 Chinese tertiary hospitals from January 2010 to May 2016. The Hepatoma Arterial-embolization Prognostic (HAP) score system and its modified versions (mHAP, mHAP2 and mHAP3), as well as the six-and-twelve criteria were compared in terms of their correlations with radiological response and overall survival (OS) prediction for first TACE. The same analyses were conducted in 912 patients receiving re-TACE to evaluate the ART (assessment for re-treatment with TACE) and ABCR (alpha-fetoprotein, Barcelona Clinic Liver Cancer, Child-Pugh and Response) systems for post re-TACE survival (PRTS). RESULTS: All the prognostic systems were correlated with radiological response achieved by first TACE, and the six-and-twelve criteria exhibited the highest correlation (Spearman R = 0.39, P = 0.026) and consistency (Kappa = 0.14, P = 0.019), with optimal performance by area under the receiver operating characteristic curve of 0.71 [95% confidence interval (CI): 0.68-0.74]. With regard to the prediction of OS, the mHAP3 system identified patients with a favorable outcome with the highest concordance (C)-index of 0.60 (95%CI: 0.57-0.62) and the best area under the receiver operating characteristic curve at any time point during follow-up; whereas, PRTS was well-predicted by the ABCR system with a C-index of 0.61 (95%CI: 0.59-0.63), rather than ART. Finally, combining the mHAP3 and ABCR systems identified candidates suitable for TACE with an improved median PRTS of 36.6 mo, compared with non-candidates with a median PRTS of 20.0 mo (log-rank test P < 0.001). CONCLUSION: Radiological response to TACE is closely associated with tumor burden, but superior prognostic prediction could be achieved with the combination of mHAP3 and ABCR in patients with unresectable liver-confined HCC.

BMP2 secretion from hepatocellular carcinoma cell HepG2 enhances angiogenesis and tumor growth in endothelial cells via activation of the MAPK/p38 signaling pathway.

BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most common tumors globally, with varying prevalence based on endemic risk factors. Bone morphogenetic protein (BMP) exhibits a broad spectrum of biological activities in various tissues including angiogenesis. Here, this study aimed to investigate the mechanism of BMP2 in HCC by mediating the mitogen-activated protein kinase (MAPK)/p38 signaling pathway. METHODS: BMP2 expression was quantified in HCC and adjacent tissues. BMP2 gain- and loss-of-function experiments were conducted by infection with lentivirus over-expressing BMP2 or expressing shRNA against BMP2. The angiogenesis was evaluated with HepG2 cells co-cultured with ECV304 cells. SB-239063 was applied to inhibit the activation of the MAPK/p38 signaling pathway so as to identify the significance of this pathway in HCC progression. Finally, in vivo experiments were conducted to identify the role of BMP2 and the MAPK/p38 signaling pathway in tumor growth and angiogenesis. RESULTS: BMP2 was highly expressed in HCC. Over-expression of BMP2 was found to accelerate cell proliferation, migration, invasion, microvascular density, and angiogenesis and decrease cell apoptosis in vitro and in vivo. BMP2 silencing exhibited inhibitory effects on HCC cell invasion and angiogenesis. The co-culture system illustrated that HepG2 cells secreted BMP2 in ECV304, and silenced BMP2 in HepG2 cells resulted in the inactivation of the MAPK/p38 signaling pathway, thus suppressing cancer progression, tumor growth, and angiogenesis in HCC. CONCLUSION: Taken together, the key findings of this study propose that silencing of BMP2 inhibits angiogenesis and tumor growth in HCC, highlighting BMP2 silencing as a potential strategy for the treatment of HCC.

Antiplasmodial and antimalarial activities of quinolone derivatives: An overview.

Malaria remains one of the most deadly infectious diseases globally. Considering the growing spread of resistance, development of new and effective antimalarials remains an urgent priority. Quinolones, which are emerged as one of the most important class of antibiotics in the treatment of various bacterial infections, showed potential in vitro antiplasmodial and in vivo antimalarial activities, making them promising candidates for the chemoprophylaxis and treatment of malaria. This review presents the current progresses and applications of quinolone-based derivatives as potential antimalarials to pave the way for the development of new antimalarials.

Fluoroquinolone derivatives and their anti-tubercular activities.

Tuberculosis (TB) remains one of the most widespread and leading deadliest diseases, around one-third of the world's population harbor a latent infection by Mycobacterium tuberculosis (MTB), and 5-10% eventually develop an active TB. The emergency of MTB new virulent forms as well as the co-infection between MTB and HIV alarming the serious problem in TB control and demanding the need for new drugs more potent than earlier with safe ADME profile. Fluoroquinolones are emerged as a large family of synthetic broad spectrum antibiotics, and some of them were recommended as the second-line agents for the treatment of TB mainly in cases involving resistance or intolerance to first-line anti-TB therapy by WHO. Numerous of FQs derivatives have been synthesized for seeking for new anti-TB agents, and some of them exhibited promising potency. This review aims to summarize the recent advances made towards the discovery of FQs derivatives as anti-TB agents and the structure-activity relationship of these derivatives.

Influence of Cr(III) and Cr(VI) on the interaction between sparfloxacin and calf thymus DNA.

Cr(III) and Cr(VI) have different binding capacity with sparfloxacin, and have different combination modes with calf thymus DNA. Selecting these two different metal ions, the influence of them on the binding constants between sparfloxacin (SPFX) and calf thymus DNA, as well as the related mechanism has been studied by using absorption and fluorescence spectroscopy. The result shows that Cr(III) has weaker binding capacity to SPFX in the SPFX-Cr(III) binary system, but influences the binding between SPFX and DNA obviously in SPFX-DNA-Cr(III) ternary system. However, although Cr(VI) has a stronger binding capacity to SPFX, it has no effect on the binding between SPFX and DNA. Referring to the different modes of Cr(III) and Cr(VI) binding to DNA, the mechanism of the influence of metal ions on the binding between SPFX and DNA has been proposed. SPFX can directly bind to DNA by chelating DNA base sites. If a metal ion at certain concentration binds mainly to DNA bases, it can decrease the binding constants between SPFX and DNA through competing with SPFX. While if a metal ion at certain concentration mainly binds to phosphate groups of DNA, it can increase the binding constants by building a bridge between SPFX and DNA. If a metal ion at certain concentrations binds neither to bases nor phosphate groups in DNA, it will have no effect on the binding constant between SPFX and DNA. Our result supports Palumbo's conclusion that the binding between SPFX and the phosphata groups is the precondition for the combination between SPFX and DNA, which is stabilized through stacking interactions between the condensed rings of SPFX and DNA bases.

Preparation and characterization of a potent, long-lasting recombinant human serum albumin-interferon-alpha2b fusion protein expressed in Pichia pastoris.

A long-lasting recombinant human serum albumin-interferon-alpha2b fusion protein (rHSA/IFNalpha2b) was prepared and its structure and biological activities were studied. rHSA/IFNalpha2b was expressed in methylotrophic yeast Pichia pastoris with HSA's natural signal peptide and purified by dye affinity chromatography, hydrophobic interaction chromatography, ion exchange chromatography and Sephadex G25. Purity of the prepared rHSA/IFNalpha2b was greater than 97% analyzed by non-reduced SDS-PAGE and RP-HPLC. Structure and biological activities of the prepared rHSA/IFNalpha2b were characterized by physical, chemical and biological methods. Its pI was 5.3 and showed a single band on IEF gel. Molecular weight determined by MALDI-TOF was 86004.3+/-29.2. Amino-terminal and carboxyl-terminal amino acid sequences were identical to predicted sequence. Its specific activity in vitro was 6.3+/-0.8x10(5) IU/mg fusion protein, retaining about 1.4% of that of unmodified rIFNalpha on a molar basis. After administered in monkeys, significant increases of 2',5'-oligoadenylate synthetase activity relative to IFN-alpha were maintained for 14 days in serum and the rHSA/IFNalpha2b showed more potent biological activity than IFN-alpha on a molar basis. Therefore, markedly improved in vivo biological activity of rHSA/IFNalpha2b could exhibit more potent antiviral activity than IFNalpha2b in future clinical trials.