Characterization of a novel T cell-engaging bispecific antibody for elimination of L1CAM-positive tumors.

Neural cell adhesion molecule L1 (L1CAM) is a cell-surface glycoprotein involved in cancer occurrence and migration. Up to today, L1CAM-targeted therapy appeared limited efficacy in clinical trials although quite a few attempts by monoclonal antibody (mAb) or chimeric antigen receptor T-cell therapy (CAR-T) have been reported. Therefore, the development of new effective therapies targeting L1CAM is highly desirable. It has been demonstrated that T cell-engaging bispecific antibody (TCE) plays an effective role in cancer immunotherapy by redirecting the cytotoxic activity of CD3+ T cells to tumor cells, resulting in tumor cell death. In this study, we designed and characterized a novel bispecific antibody (CE7-TCE) based on the IgG-(L)-ScFv format, which targets L1CAM and CD3 simultaneously. In vitro, CE7-TCE induced specific killing of L1CAM-positive tumor cells through T cells. In vivo, CE7-TCE inhibited tumor growth in human peripheral blood mononuclear cell/tumor cell co-grafting models. To overcome the adaptive immune resistance (AIR) that impairs the efficacy of TCEs, we conducted a combination therapy of CE7-TCE with Pembrolizumab (anti-PD1 mAb), which enhanced the anti-tumor activity of CE7-TCE. Our results confirmed the feasibility of using L1CAM as a TCE target for the treatment of solid tumors and revealed the therapeutic potential of CE7-TCE combined with immune checkpoint inhibitors.

A novel bispecific antibody drug conjugate targeting HER2 and HER3 with potent therapeutic efficacy against breast cancer.

Antibody drug conjugate (ADC) therapy has become one of the most promising approaches in cancer immunotherapy. Bispecific targeting could enhance the efficacy and safety of ADC by improving its specificity, affinity and internalization. In this study we constructed a HER2/HER3-targeting bispecific ADC (BsADC) and characterized its physiochemical properties, target specificity and internalization in vitro, and assessed its anti-tumor activities in breast cancer cell lines and in animal models. The HER2/HER3-targeting BsADC had a drug to antibody ratio (DAR) of 2.89, displayed a high selectivity against the target JIMT-1 breast cancer cells in vitro, as well as a slightly higher level of internalization than HER2- or HER3-monospecific ADCs. More importantly, the bispecific ADC potently inhibited the viability of MCF7, JIMT-1, BT474, BxPC-3 and SKOV-3 cancer cells in vitro. In JIMT-1 breast cancer xenograft mice, a single injection of bispecific ADC (3 mg/kg, i.v.) significantly inhibited the tumor growth with an efficacy comparable to that caused by combined injection of HER2 and HER3-monospecific ADCs (3 mg/kg for each). Our study demonstrates that the bispecific ADC concept can be applied to development of more potent new cancer therapeutics than the monospecific ADCs.

Concurrent Dual-Contrast Enhancement Using Fe3O4 Nanoparticles to Achieve a CEST Signal Controllability.

Traditional T2 magnetic resonance imaging (MRI) contrast agents have defects inherent to negative contrast agents, while chemical exchange saturation transfer (CEST) contrast agents can quantify substances at trace concentrations. After reaching a certain concentration, iron-based contrast agents can "shut down" CEST signals. The application range of T2 contrast agents can be widened through a combination of CEST and T2 contrast agents, which has promising application prospects. The purpose of this study is to develop a T2 MRI negative contrast agent with a controllable size and to explore the feasibility of dual contrast enhancement by combining T2 with CEST contrast agents. The study was carried out in vitro with HCT-116 human colon cancer cells. A GE SIGNA Pioneer 3.0 T medical MRI scanner was used to acquire CEST images with different saturation radio-frequency powers (1.25/2.5/3.75/5 µT) by 2D spin echo-echo planar imaging (SE-EPI). Magnetic resonance image compilation (MAGiC) was acquired by a multidynamic multiecho 2D fast spin-echo sequence. The feasibility of this dual-contrast enhancement method was assessed by scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering, ζ potential analysis, inductively coupled plasma, X-ray photoelectron spectroscopy, X-ray powder diffraction, vibrating-sample magnetometry, MRI, and a Cell Counting Kit-8 assay. The association between the transverse relaxation rate r2 and the pH of the iron-based contrast agents was analyzed by linear fitting, and the linear relationship between the CEST effect in different B1 fields and pH was analyzed by the ratio method. Fe3O4 nanoparticles (NPs) with a mean particle size of 82.6 ± 22.4 nm were prepared by a classical process, and their surface was successfully modified with -OH active functional groups. They exhibited self-aggregation in an acidic environment. The CEST effect was enhanced as the B1 field increased, and an in vitro pH map was successfully plotted using the ratio method. Fe3O4 NPs could stably serve as reference agents at different pH values. At a concentration of 30 µg/mL, Fe3O4 NPs "shut down" the CEST signals, but when the concentration of Fe3O4 NPs was less than 10 µg/mL, the two contrast agents coexisted. The prepared Fe3O4 NPs had almost no toxicity, and when their concentration rose to 200 µg/mL at pH 6.5 or 7.4, they did not reach the half-maximum inhibitory concentration (IC50). Fe3O4 magnetic NPs with a controllable size and no toxicity were successfully synthesized. By combining Fe3O4 NPs with a CEST contrast agent, the two contrast agents could be imaged simultaneously; at higher concentrations, the iron-based contrast agent "shut down" the CEST signal. An in vitro pH map was successfully plotted by the ratio method. CEST signal inhibition can be used to realize the pH mapping of solid tumors and the identification of tumor active components, thus providing a new imaging method for tumor efficacy evaluation.

Binding domain on CD22 molecules contributing to the biological activity of T cell-engaging bispecific antibodies.

CD22, as the B-cell malignancies antigen, has been targeted for immunotherapies through CAR-T cells, antibody-drug conjugates (ADCs) and immunotoxins via interaction of antibodies with binding domains on the receptor. We hypothesized that avidity and binding domain of antibody to target cells may have significant impact on the biological function in tumor immunotherapy, and T cell-engaging bispecific antibody (TCB) targeting CD22 could be used in the therapy of hematologic malignancies. So, to address the question, we utilized the information of six previously reported CD22 mAbs to generate CD22-TCBs with different avidity to different domains on CD22 protein. We found that the avidity of CD22-TCBs to protein was not consistent with the avidity to target cells, indicating that TCBs had different binding mode to the protein and cells. In vitro results indicated that CD22-TCBs mediated cytotoxicity depended on the avidity of antibodies to target cells rather than to protein. Moreover, distal binding domain of the antigen contributed to the avidity and biological activity of IgG-[L]-scfv-like CD22-TCBs. The T cells' proliferation, activation, cytotoxicity as well as cytokine release were compared, and G5/44 BsAb was selected for further in vivo assessment in anti-tumor activity. In vivo results demonstrated that CD22-TCB (G5/44 BsAb) significantly inhibited the tumors growth in mice. All these data suggested that CD22-TCBs could be developed as a promising candidate for B-cell malignancies therapy through optimizing the design with avidity and binding domain to CD22 target in consideration.

A Gold Nanocage Probe Targeting Survivin for the Diagnosis of Pancreatic Cancer.

In this paper, Au nanocages (AuNCs) loaded with the MRI contrast agent gadolinium (Gd) and capped with the tumor-targeting gene survivin (Sur-AuNC•Gd-Cy7 nanoprobes) were designed and applied as a targeted imaging agent for pancreatic cancer. With its capacity to transport fluorescent dyes and MR imaging agents, the gold cage is an outstanding platform. Furthermore, it has the potential to transport different drugs in the future, making it a unique carrier platform. The utilization of Sur-AuNC•Gd-Cy7 nanoprobes has proven to be an effective means of targeting and localizing survivin-positive BxPC-3 cells within their cytoplasm. By targeting survivin, an antiapoptotic gene, the Sur-AuNC•Gd-Cy7 nanoprobe was able to induce pro-apoptotic effects in BxPC-3 pancreatic cancer cells. The biocompatibility of AuNCs•Gd, AuNCs•Gd-Cy7 nanoparticles, and Sur-AuNC•Gd-Cy7 nanoprobes is evaluated through the hemolysis rate assay. The stability of AuNCs•Gd, AuNCs•Gd-Cy7 nanoparticles, and Sur-AuNC•Gd-Cy7 nanoprobes was evaluated by determining their hydrodynamic dimensions following storage in different pH solutions for a corresponding duration. Excellent biocompatibility and stability of the Sur-AuNC•Gd-Cy7 nanoprobes will facilitate their further utilization in vivo and in vitro. The surface-bound survivin plays a role in facilitating the Sur-AuNC•Gd-Cy7 nanoprobes' ability to locate the BxPC-3 tumor. The probe was modified to incorporate Gd and Cy7, thereby enabling the simultaneous utilization of magnetic resonance imaging (MRI) and fluorescence imaging (FI) techniques. In vivo, the Sur-AuNC•Gd-Cy7 nanoprobes were found to effectively target and localize survivin-positive BxPC-3 tumors through the use of MRI and FI. After being injected via the caudal vein, the Sur-AuNC•Gd-Cy7 nanoprobes were found to accumulate effectively in an in situ pancreatic cancer model within 24 h. Furthermore, these nanoprobes were observed to be eliminated from the body through the kidneys within 72 h after a single injection. This characteristic is crucial for a diagnostic agent. Based on the aforementioned outcomes, the Sur-AuNC•Gd-Cy7 nanoprobes have significant potential advantages for the theranostic treatment of pancreatic cancer. This nanoprobe possesses distinctive characteristics, such as advanced imaging abilities and specific drug delivery, which offer the possibility of enhancing the precision of diagnosis and efficacy of treatment for this destructive illness.

Comparison of efficacy and safety between endoscopic mucosal dissection and resection in the treatment of early gastrointestinal cancer and precancerous lesions: a systematic review and meta-analysis.

Background: Endoscopic mucosal dissection (EMD) is a new treatment method. Whether its clinical efficacy and safety are superior to surgical resection is still controversial. The sample size of previous studies on EMD for the treatment of early cancer of digestive tract is small, and there is no reliable evidence at present. Therefore, it is necessary to evaluate the efficacy and safety of EMD based on the evidence of evidence-based medicine. Methods: The PubMed, Web of Science, Cochrane Library, Embase, China National Knowledge Infrastructure, Wanfang, cqvip.com (VIP), websites and citation searching were searched to obtain relevant literature on EMD for early cancer and precancerous lesions of digestive tract. The retrieval time was from the establishment of the database to November 29th, 2022. Literature was screened according to inclusion and exclusion criteria and data and data were extracted. The final included literature was assessed by Cochrane risk of bias tool, and publication bias was assessed by Egger's test. Results: A total of 10 articles were included, with a total of 1,165 patients. Among these, 585 cases were treated with EMD and 580 cases were in the control group. The literature quality evaluation found that 5 articles had low risk of bias and 5 articles had unclear risk of bias. The results showed that the complete resection rate in the observation group was higher than that in the control group [risk ratio (RR) =1.25, 95% confidence interval (CI): 1.15-1.35, P<0.01]. Cumulative intraoperative blood loss (P<0.01), operation time (P<0.01), postoperative complications (P<0.01), hospital stay (P<0.01), and hospitalization expenses (P<0.01) in the observation group were lower than those in the control group. Conclusions: EMD for early gastrointestinal cancer and precancerous lesions can improve the complete resection rate of tumors; reduce intraoperative blood loss, complications, operation time, and hospitalization time and cost. However, due to the small number of literatures included in this paper, the quality of literatures is not high, and some results have heterogeneous interference, the conclusion needs to include more high-treatment studies for further study.

Microenvironment-responsive anti-PD-L1 × CD3 bispecific T-cell engager for solid tumor immunotherapy.

Bispecific T-cell Engager (BiTE) antibodies can redirect T-cells to tumor cells, and turn on the targeted lysis of tumor cells. However, BiTE has been challenging in solid tumors due to short plasma half-life, "off-target" effect, and immunosuppression via PD-1/PD-L1 axis. This study designed a safe, long-acting, and highly effective Protease-Activated PSTAGylated BiTE, named PAPB, which includes a shielding polypeptide domain (PSTAG), a protease-activated linker, and a BiTE core. The BiTE core consists of two scFvs targeting PD-L1 and CD3. BiTE core bound PD-L1 and CD3 in a dose-dependent manner, and PAPB can release BiTE core in response to MMP2 in the tumor microenvironment to exert antitumor activity. The plasma half-life of PAPB in mice was significantly prolonged from 2.46 h to 6.34 h of the BiTE core. In mice bearing melanoma (A375) xenografts, PAPB significantly increased infiltration of T lymphocytes in tumor tissue, and inhibited tumor proliferation without activating T-cells in the peripheral blood. Overall, the engineering protein PAPB could be a promising drug candidate for solid tumor immunotherapy.

Long-term passaging of pseudo-typed SARS-CoV-2 reveals the breadth of monoclonal and bispecific antibody cocktails.

The continuous emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants poses challenges to the effectiveness of neutralizing antibodies. Rational design of antibody cocktails is a realizable approach addressing viral immune evasion. However, evaluating the breadth of antibody cocktails is essential for understanding the development potential. Here, based on a replication competent vesicular stomatitis virus model that incorporates the spike of SARS-CoV-2 (VSV-SARS-CoV-2), we evaluated the breadth of a number of antibody cocktails consisting of monoclonal antibodies and bispecific antibodies by long-term passaging the virus in the presence of the cocktails. Results from over two-month passaging of the virus showed that 9E12 + 10D4 + 2G1 and 7B9-9D11 + 2G1 from these cocktails were highly resistant to random mutation, and there was no breakthrough after 30 rounds of passaging. As a control, antibody REGN10933 was broken through in the third passage. Next generation sequencing was performed and several critical mutations related to viral evasion were identified. These mutations caused a decrease in neutralization efficiency, but the reduced replication rate and ACE2 susceptibility of the mutant virus suggested that they might not have the potential to become epidemic strains. The 9E12 + 10D4 + 2G1 and 7B9-9D11 + 2G1 cocktails that picked from the VSV-SARS-CoV-2 system efficiently neutralized all current variants of concern and variants of interest including the most recent variants Delta and Omicron, as well as SARS-CoV-1. Our results highlight the feasibility of using the VSV-SARS-CoV-2 system to develop SARS-CoV-2 antibody cocktails and provide a reference for the clinical selection of therapeutic strategies to address the mutational escape of SARS-CoV-2.

Pralsetinib for the treatment of a RET-positive advanced non-small-cell lung cancer patient harboring both ANK-RET and CCDC6-RET fusions with coronary heart disease: a case report.

Background: Rearranged during transfection (RET) is one of the rare driver genes of non-small-cell lung cancer (NSCLC), having a gene fusion incidence of 1-2% in NSCLC. Before the emergence of specific RET inhibitors, multikinase inhibitors such as cabozantinib and vandetanib were tried for RET fusion-positive NSCLC, but their efficacies were poor, and the U.S. Food and Drug Administration did not approve the application of these drugs for such patients. In the phase I/II ARROW clinical trial, pralsetinib significantly improved the overall remission rate and disease progression-free survival (PFS) of RET fusion-positive NSCLC patients. In the clinic, it is necessary to conduct adequate molecular screening of patients to guide drug choices. With the wide application of second-generation sequencing technology in clinical practice, many RET fusion partners have been discovered. It is rare for one patient with two RET fusions. Case Description: This paper reports a rare case of RET dual fusion in an advanced NSCLC patient who had coronary heart disease. After the failure of first-line treatment with platinum-based chemotherapy and post-line treatment with small-molecule targeted therapy of anlotinib and alectinib, the application of pralsetinib (400 mg, qd) reduced the tumor volume by 79% and achieved partial remission (based on the evaluation criteria of the World Health Organization) or reduced tumor volume by 17% (based on the Response Evaluation Criteria in Solid Tumors). It had an overall manageable safety profile. Conclusions: This patient with two different RET fusions was sensitive to pralsetinib. Patients with well-controlled coronary heart disease and recurrent myocardial infarction might benefit from pralsetinib. The pathogenesis of RET-dual-fusion NSCLC and its clinical impact need to be further studied to provide a theoretical basis for personalized treatment.

Cystic Neoplasms of the Pancreas: Differential Diagnosis and Radiology Correlation.

Although the probability of pancreatic cystic neoplasms (PCNs) being detected is raising year by year, their differential diagnosis and individualized treatment are still a challenge in clinical work. PCNs are tumors containing cystic components with different biological behaviors, and their clinical manifestations, epidemiology, imaging features, and malignant risks are different. Some are benign [e.g., serous cystic neoplasms (SCNs)], with a barely possible that turning into malignant, while others display a low or higher malignant risk [e.g., solid pseudopapillary neoplasms (SPNs), intraductal papillary mucinous neoplasms (IPMNs), and mucinous cystic neoplasms (MCNs)]. PCN management should concentrate on preventing the progression of malignant tumors while preventing complications caused by unnecessary surgical intervention. Clinically, various advanced imaging equipment are usually combined to obtain a more reliable preoperative diagnosis. The challenge for clinicians and radiologists is how to accurately diagnose PCNs before surgery so that corresponding surgical methods and follow-up strategies can be developed or not, as appropriate. The objective of this review is to sum up the clinical features, imaging findings and management of the most common PCNs according to the classic literature and latest guidelines.

Broad ultra-potent neutralization of SARS-CoV-2 variants by monoclonal antibodies specific to the tip of RBD.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants of concern (VOCs) continue to wreak havoc across the globe. Higher transmissibility and immunologic resistance of VOCs bring unprecedented challenges to epidemic extinguishment. Here we describe a monoclonal antibody, 2G1, that neutralizes all current VOCs and has surprising tolerance to mutations adjacent to or within its interaction epitope. Cryo-electron microscopy structure showed that 2G1 bound to the tip of receptor binding domain (RBD) of spike protein with small contact interface but strong hydrophobic effect, which resulted in nanomolar to sub-nanomolar affinities to spike proteins. The epitope of 2G1 on RBD partially overlaps with angiotensin converting enzyme 2 (ACE2) interface, which enables 2G1 to block interaction between RBD and ACE2. The narrow binding epitope but high affinity bestow outstanding therapeutic efficacy upon 2G1 that neutralized VOCs with sub-nanomolar half maximal inhibitory concentration in vitro. In SARS-CoV-2, Beta or Delta variant-challenged transgenic mice and rhesus macaque models, 2G1 protected animals from clinical illness and eliminated viral burden, without serious impact to animal safety. Mutagenesis experiments suggest that 2G1 is potentially capable of dealing with emerging SARS-CoV-2 variants in the future. This report characterized the therapeutic antibodies specific to the tip of spike against SARS-CoV-2 variants and highlights the potential clinical applications as well as for developing vaccine and cocktail therapy.

Identification of Predominant Histopathological Growth Patterns of Colorectal Liver Metastasis by Multi-Habitat and Multi-Sequence Based Radiomics Analysis.

Purpose: Developing an MRI-based radiomics model to effectively and accurately predict the predominant histopathologic growth patterns (HGPs) of colorectal liver metastases (CRLMs). Materials and Methods: In this study, 182 resected and histopathological proven CRLMs of chemotherapy-naive patients from two institutions, including 123 replacement CRLMs and 59 desmoplastic CRLMs, were retrospectively analyzed. Radiomics analysis was performed on two regions of interest (ROI), the tumor zone and the tumor-liver interface (TLI) zone. Decision tree (DT) algorithm was used for radiomics modeling on each MR sequence, and fused radiomics model was constructed by combining the radiomics signature of each sequence. The clinical and combination models were developed through multivariate logistic regression method. The performance of the developed models was assessed by receiver operating characteristic (ROC) curves with indicators of area under curve (AUC), accuracy, sensitivity, and specificity. A nomogram was constructed to evaluate the discrimination, calibration, and usefulness. Results: The fused radiomicstumor and radiomicsTLI models showed better performance than any single sequence and clinical model. In addition, the radiomicsTLI model exhibited better performance than radiomicstumor model (AUC of 0.912 vs. 0.879) in internal validation cohort. The combination model showed good discrimination, and the AUC of nomogram was 0.971, 0.909, and 0.905 in the training, internal validation, and external validation cohorts, respectively. Conclusion: MRI-based radiomics method has high potential in predicting the predominant HGPs of CRLM. Preoperative non-invasive identification of predominant HGPs could further explore the ability of HGPs as a potential biomarker for clinical treatment strategy, reflecting different biological pathways.

Tumor targeting and microenvironment-responsive multifunctional fusion protein for pro-apoptotic peptide delivery.

The great therapeutic potential of peptides has not yet been achieved, mainly due to their remarkably short in vivo half-life. Although conjugation to macromolecules has been an effective way of improving protein in vivo half-life, the steric hindrance of macromolecules usually reduces the in vivo efficacy of peptides. Here we report a complex delivery system made from PsTag polypeptide, polyglutamic acid chain, matrix metalloproteinase 2 (MMP2)-degradable domain and cationic cell penetrating peptide for anticancer peptide delivery. Clear evidence was shown in vitro and in vivo to demonstrate that this multifunctional protein fusing a pro-apoptotic KLAKLAKKLAKLAK (KLA), named PAK, can increase circulation time in blood, enhance accumulation at tumor sites, eliminate the PsTag domain and the polyanionic sequence when triggered by tumor overexpressing MMP2, and then expose the cell penetrating peptide to realize the potent cellular uptake of KLA. Treatment of tumor-bearing mice with PAK could markedly induce tumor cells apoptosis and inhibit tumor growth, with no significant adverse effects. These results suggest our fusion protein can be a potential delivery system for peptide delivery in cancer treatments.

Microenvironment-Responsive Delivery of the Cas9 RNA-Guided Endonuclease for Efficient Genome Editing.

Successful and efficient delivery of Cas9 protein and gRNA into cells is critical for genome editing and its therapeutic application. In this study, we developed an improved supercharged polypeptide (SCP) mediated delivery system based on dithiocyclopeptide linker to realize the effective genome editing in tumor cells. The fusion protein Cas9-linker-SCP (Cas9-LS) forms positively charged complexes with gRNA in vitro to provide possibilities for gRNA delivery into cells. Under the microenvironment of tumor cells, the dithiocyclopeptide linker, containing matrix metalloproteinase 2 (MMP-2) sensitive sequence and an intramolecular disulfide bond, can be completely disconnected to promote the release of Cas9 protein with the nuclear localization sequence (NLS) in the cytoplasm and transfer to the cell nucleus for highly efficient genome editing, resulting in an obvious increase of indel efficiency in comparison to fusion protein without dithiocyclopeptide linker (Cas9-SCP). Furthermore, Cas9-LS shows no significant cytotoxicity and minimal hemolytic activity. We envision that the microenvironment-responsive Cas9 protein delivery system can facilitate more efficient genome editing in tumor cells.

Three-Dimensional CT Texture Analysis to Differentiate Colorectal Signet-Ring Cell Carcinoma and Adenocarcinoma.

PURPOSE: The objective of this research was to validate the diagnostic value of three-dimensional texture parameters and clinical characteristics in the differentiation of colorectal signet-ring cell carcinoma (SRCC) and adenocarcinoma (AC). METHODS: We retrospectively analyzed data from 102 patients with SRCC or AC confirmed by pathology, including 51 SRCC (from January 2015 to July 2019) and 51 AC patients (from January 2019 to July 2019). CT findings and clinical data, including age, gender, clinical symptoms, serological biomarkers, tumor size, and tumor location, were compared between SRCC and AC. CT texture features were quantified on portal phase images using three-dimensional analysis. A list of texture parameters was generated with MaZda software for the classification of tumors. The texture features, clinical data and CT findings were statistically analyzed for the discrimination ability of SRCC and AC, and the potential predictive parameters that may be used to differentiate the two groups were subsequently tested using the least absolute shrinkage and selection operator (LASSO) and logistic regression analyses. The receiver operating characteristic curve (ROC) provided a range of values for establishing the cutoff value, as well as the sensitivity and specificity of prediction for each significant variable. RESULTS: SRCC occurred more often in men than AC did (80.39% vs 49.02%, P < 0.01). The patients were younger in the SRCC group than in the AC group, without a statistically significant difference (55.84 vs 59.20 years, P = 0.216). There were no significant differences in the clinical symptoms, tumor size, or tumor location between the two groups (P=0.505, P=0.19, P=0.843, respectively). The elevation of serological biomarker CA724 was more common in SRCC than in AC (P< 0.001). Perc.01%3D, Perc.10%3D and s(1,0,0) SumAverg were lower in the SRCC group than in the AC group during the portal phase, with the areas under curve (AUCs) of 0.892-0.929, sensitivity of 76.5-84.3% and specificity of 88.2-96.1%. In the differentiation between SRCC and AC, the 1-NN minimal classification error (MCR) was 29.41%. CONCLUSION: Three-dimensional texture parameters, including Perc.01%3D, Perc.10%3D and s(1,0,0) SumAverg, exhibited a favorable discriminatory ability to distinguish SRCC from AC.

Engineering Extracellular Expression Systems in Escherichia coli Based on Transcriptome Analysis and Cell Growth State.

Escherichia coli extracellular expression systems have a number of advantages over other systems, such as lower pyrogen levels and a simple purification process. Various approaches, such as the generation of leaky mutants via chromosomal engineering, have been explored for this expression system. However, extracellular protein yields in leaky mutants are relatively low compared to that in intracellular expression systems and therefore need to be improved. In this work, we describe the construction, characterization, and mechanism of enhanced extracellular expression in Escherichia coli. On the basis of the localizations, functions, and transcription levels of cell envelope proteins, we systematically elucidated the effects of multiple gene deletions on cell growth and extracellular expression using modified CRISPR/Cas9-based genome editing and a FlAsH labeling assay. High extracellular yields of heterologous proteins of different sizes were obtained by screening multiple gene mutations. The enhancement of extracellular secretion was associated with the derepression of translation and translocation. This work utilized universal methods in the design of extracellular expression systems for genes not directly associated with protein synthesis that were used to generate strains with higher protein expression capability. We anticipate that extracellular expression systems may help to shed light on the poorly understood aspects of these secretion processes as well as to further assist in the construction of engineered prokaryotic cells for efficient extracellular production of heterologous proteins.

Plectin-1 Targeted Dual-modality Nanoparticles for Pancreatic Cancer Imaging.

BACKGROUND: Biomarker-targeted molecular imaging holds promise for early detection of pancreatic cancer. The aim of this study was to design and evaluate a plectin-1 targeted multi-functional nanoparticle probe for pancreatic cancer imaging. METHODS: 1,2-Distearoyl-sn-glycero-3-phosphoethanolamine-N-amino(polyethylene glycol) (DSPE-PEG-NH2)-modified superparamagnetic iron oxide (Fe3O4) nanoparticles (SPION) were conjugated with plectin-1 antibody and/or Cy7 to create the multi-functional targeted nanoparticle targeted probe (Plectin-SPION-Cy7) or non-targeted probe (SPION-Cy7). Pancreatic carcinoma cell lines expressing plectin-1 were cultured with the targeted or control probes and then were imaged using confocal laser scanning microscopy and magnetic resonance imaging (MRI). Accumulations of the nanoparticles in pancreatic tumor xenografted mice were determined by MRI and fluorescence imaging. RESULTS: In vitro optical imaging and MRI showed that the targeted nanoparticles were highly accumulated in MIAPaCa2 and XPA-1 carcinoma cells but not in non-carcinoma MIN6 cells, which was further confirmed by Prussian blue staining. In vivo MRI showed a significant T2 signal reduction. Prussian blue staining further confirmed that the plectin-1 targeted nanoparticles were highly accumulated in the tumor mass but not in normal pancreatic tissues, or in the liver and kidney, and few nanoparticles were observed in the tumors of mice injected with SPION-Cy7. CONCLUSIONS: Our data demonstrate that plectin-1 targeted fluorescence and MR dual-functional nanoparticle can visualize pancreatic cancer, and it has great potential to be used with various imaging devices for pancreatic cancer detection.

MRI findings of low-grade fibromyxoid sarcoma: a case report and literature review.

BACKGROUND: Low-grade fibromyxoid sarcoma (LGFMS) is a distinctive slow growing soft tissue neoplasm, mostly affecting young individuals with no gender difference. It usually arises in deep soft tissue of the lower limbs and trunk, but few cases of LGFMS located in pelvis have been reported. CASE PRESENTATION: We describe the magnetic resonance imaging(MRI) features of LGFMS located in the anterior pelvic wall of a 21-year-old female and correlate them with clinicopathological features. The tumor was completely resected and there is no recidivism during the follow-up one year. CONCLUSIONS: We report on the radiological findings of LGFMS with histological correlation. Awareness of the imaging features may be useful for the diagnosis of LGFMS and helpful to distinguish among mimics.