Enhancing tylosin production by combinatorial overexpression of efflux, SAM biosynthesis, and regulatory genes in hyperproducing Streptomyces xinghaiensis strain.

Tylosin is a 16-membered macrolide antibiotic widely used in veterinary medicine to control infections caused by Gram-positive pathogens and mycoplasmas. To improve the fermentation titer of tylosin in the hyperproducing Streptomyces xinghaiensis strain TL01, we sequenced its whole genome and identified the biosynthetic gene cluster therein. Overexpression of the tylosin efflux gene tlrC, the cluster-situated S-adenosyl methionine (SAM) synthetase gene metKcs, the SAM biosynthetic genes adoKcs-metFcs, or the pathway-specific activator gene tylR enhanced tylosin production by 18%, 12%, 11%, and 11% in the respective engineered strains TLPH08-2, TLPH09, TLPH10, and TLPH12. Co-overexpression of metKcs and adoKcs-metFcs as two transcripts increased tylosin production by 22% in the resultant strain TLPH11 compared to that in TL01. Furthermore, combinational overexpression of tlrC, metKcs, adoKcs-metFcs, and tylR as four transcripts increased tylosin production by 23% (10.93g/L) in the resultant strain TLPH17 compared to that in TL01. However, a negligible additive effect was displayed upon combinational overexpression in TLPH17 as suggested by the limited increment of fermentation titer compared to that in TLPH08-2. Transcription analyses indicated that the expression of tlrC and three SAM biosynthetic genes in TLPH17 was considerably lower than that of TLPH08-2 and TLPH11. Based on this observation, the five genes were rearranged into one or two operons to coordinate their overexpression, yielding two engineered strains TLPH23 and TLPH24, and leading to further enhancement of tylosin production over TLPH17. In particular, the production of TLPH23 reached 11.35 g/L. These findings indicated that the combinatorial strategy is a promising approach for enhancing tylosin production in high-yielding industrial strains.

Breast-conserving surgery and sentinel lymph node biopsy for breast cancer and their correlation with the expression of polyligand proteoglycan-1.

BACKGROUND: Breast cancer is a malignant tumor with an unclear etiology and is the most common malignant tumor in women. Surgery is the main clinical treatment for breast cancer. Although traditional total mastectomy combined with axillary lymph node dissection is effective, it can result in shoulder dysfunction, especially in middle-aged and elderly patients with breast cancer with weak constitution and other underlying diseases. Furthermore, the postoperative quality of life is poor. AIM: To assess breast-conserving surgery and sentinel lymph node biopsy for breast cancer treatment and their correlation with polyligand proteoglycan-1. METHODS: Overall, 80 patients with breast cancer treated in our hospital from January 2021 to July 2021 were retrospectively selected and divided into an observation group (n = 44) and control group (n = 36) according to the treatment plan. The observation group was treated with breast-conserving surgery and sentinel lymph node biopsy, and the control group was treated with total breast resection. Simultaneously, immunohistochemical staining was used to detect the expression of syndecan-1 (SDC-1) in the lesions, and its relationship with clinicopathological findings was analyzed. RESULTS: Intraoperative blood loss, operation time, and hospital stay in the observation group were 65.51 ± 9.94 mL, 65.59 ± 9.40 min, and 14.80 ± 3.03 d, respectively, which were significantly lower than those in the control group (P < 0.05). The incidence of postoperative complications in the observation group was 11.36%, which was significantly lower than that in the control group (P < 0.05). The positive expression rate of SDC-1 in the observation group was 25.00%, and there was no significant difference between the groups (P > 0.05). The positive expression rate of SDC-1 in patients with American Joint Committee on Cancer (AJCC) stage II was 14.29%, which was significantly lower than that in patients with AJCC stage I (P < 0.05). The positive expression of SDC-1 had no significant relationship with age, course of disease, site, tissue type, and treatment plan (P > 0.05). CONCLUSION: Breast preservation surgery and sentinel lymph node biopsy for breast cancer treatment have fewer complications and quicker recovery than those treated with total breast resection. Low SDC-1 expression in breast cancer lesions is related to AJCC staging.

EZH2, a prominent orchestrator of genetic and epigenetic regulation of solid tumor microenvironment and immunotherapy.

Immune checkpoint blockade (ICB) is regarded as a promising strategy for cancer therapy. The histone methyltransferase, Enhancer of Zeste Homolog 2 (EZH2), has been implicated in the carcinogenesis of numerous solid tumors. However, the underlying mechanism of EZH2 in cancer immunotherapeutic resistance remains unknown. EZH2 orchestrates the regulation of the innate and adaptive immune systems of the tumor microenvironment (TME). Profound epigenetic and transcriptomic changes induced by EZH2 in tumor cells and immune cells mobilize the elements of the TME, leading to immune-suppressive activity of solid tumors. In this review, we summarized the dynamic functions of EZH2 on the different components of the TME, including tumor cells, T cells, macrophages, natural killer cells, myeloid-derived suppressor cells, dendritic cells, fibroblasts, and mesenchymal stem cells. Several ongoing anti-tumor clinical trials using EZH2 inhibitors have also been included as translational perspectives. In conclusion, based combinational therapy to enable ICB could offer a survival benefit in patients with cancer.

High FAS expression correlates with a better prognosis and efficacy of taxanes and target regents in breast cancer.

BACKGROUND: FAS can serve as both an oncogene and a suppresser in different malignancies, and the prognostic value of FAS remains controversial. METHODS: The Oncomine database, KM-Plotter and bc-GenExMiner platform were adopted to analyze the prognostic value of FAS in breast cancer. Breast cancer tissue microarrays were further used to verify these data. The Cell Miner Tool was used to predict the value of FAS mRNA expression in predicting the efficacies of clinical drugs. RESULTS: We found that both FAS mRNA and protein expression level significantly reduced in breast carcinoma. In addition, high FAS expression indicates a better metastatic relapse-free survival. Interestingly, FAS was associated with a better prognosis in different subtypes of breast cancer patients, namely, only in grade II and III, lymph nodal positive or p53 wild-type patients. The data from the Cell Miner Tool revealed that FAS mRNA expression was correlated with the efficacy of the first-line chemotherapeutic taxane agents and target drugs including olaparib and everolimus. CONCLUSIONS: FAS expression correlates with a better prognosis in breast cancer and may provide an effective clinical strategy to predict the sensitivity of taxanes and targeted drugs.

miR-301b-3p Regulates Breast Cancer Cell Proliferation, Migration, and Invasion by Targeting NR3C2.

OBJECTIVES: Breast cancer is the most common malignant tumor among females, and miRNAs have been reported to play an important regulatory role in breast cancer progression. This study aimed to explore the function and underlying molecular mechanism of miR-301b-3p in breast cancer. METHODS: Differential analysis and survival analysis were performed based on the data accessed from the TCGA-BRCA dataset for identification of the target miRNA. Bioinformatics analysis was conducted to predict the downstream target gene of the miRNA. Real-time quantitative PCR was carried out to detect the expression of miR-301b-3p and nuclear receptor subfamily 3 group C member 2 (NR3C2). Western blot was used to assess the protein expression of NR3C2. Cell counting kit-8 assay was performed to evaluate the proliferation of breast cancer cells. Transwell assay was conducted to determine the migratory and invasive abilities of breast cancer cells. Dual-luciferase reporter assay was employed to verify the targeting relationship between miR-301b-3p and NR3C2. RESULTS: miR-301b-3p was elevated in breast cancer cell lines and promoted cell proliferation, migration, and invasion in terms of its biological function in breast cancer. NR3C2 was validated as a direct target of miR-301b-3p via bioinformatics analysis and dual-luciferase reporter assay, and NR3C2 was downregulated in breast cancer cell lines. The rescue experiment indicated that NR3C2 was involved in the mechanism by which miR-301b-3p regulated the malignant phenotype of breast cancer cells. CONCLUSION: The present study revealed for the first time that miR-301b-3p could foster breast cancer cell proliferation, migration, and invasion by targeting NR3C2, unveiling that miR-301b-3p is a novel carcinogen in breast cancer.

The Progress and Prospect of Tunable Organic Molecules for Organic Lithium-Ion Batteries.

Compared to inorganic electrodes, organic materials are regarded as promising electrodes for lithium-ion batteries (LIBs) due to the attractive advantages of light elements, molecular-level structural design, fast electron/ion transferring, favorable environmental impacts, and flexible feature, etc. Not only specific capacities but also working potentials of organic electrodes are reasonably tuned by polymerization, electron-donating/withdrawing groups, and multifunctional groups as well as conductive additives, which have attracted intensive attention. However, organic LIBs (OLIBs) are also facing challenges on capacity loss, side reactions, electrode dissolution, low electronic conductivity, and short cycle life, etc. Many strategies have been applied to tackle those challenges, and many inspiring results have been achieved in the last few decades. In this review, we have introduced the basic concepts of LIBs and OLIBs, followed by the typical cathode and anode materials with various physicochemical properties, redox reaction mechanisms, and evolutions of functional groups. Typical charge-discharge behaviors and molecular structures of organic electrodes are displayed. Moreover, effective strategies on addressing problems of organic electrodes are summarized to give some guidance on the synthesis of optimized organic electrodes for practical applications of OLIBs.

An ERP Study on the Auditory Stream Segregation in Cochlear Implant Simulations: Effects of Frequency Separation and Time Interval.

Auditory stream segregation is an important function of the auditory system, and the extent to which this function works has a major impact on listener's ability to recognize auditory objects in complex listening environments. However, cochlear implant (CI) listeners are poorly equipped for this challenge, mainly owing to the impoverished sensory information available via their implants. The purpose of this study was to examine two factors, i.e., frequency separation and time interval, affecting the auditory stream segregation in vocoder simulations simulating CI speech processing based on an event-related potential (ERP) experiment. The pure-tone stimuli were processed by a vocoding process, and presented to normal-hearing listeners in an ERP experiment. Experimental results showed that a large frequency separation or a short time interval led to a larger mismatch negativity (MMN) response. The MMN results in this work suggested that the degree of auditory stream segregation was affected by frequency separation and time interval, and MMN could serve as a potential index for future ERP studies on auditory stream segregation in CI users.

Factors affecting the intelligibility of high-intensity-level-based speech.

The present work examined factors affecting the intelligibility of high-intensity-level-based speech. Mandarin sentences were processed to contain only high-intensity segments confined by a 5-dB selected intensity range (SIR), with other segments replaced by noise. The processed stimuli were presented to normal-hearing listeners to recognize. The greatest intensity density occurred in the SIR with an upper boundary 3 dB below the peak intensity level, and this SIR yielded the highest intelligibility score in quiet. The SIR with the upper boundary at the peak intensity level yielded better intelligibility performance under noisy conditions, due largely to the relatively high effective signal-to-noise ratio.

Studying the Effect of Carrier Type on the Perception of Vocoded Stimuli via Mismatch Negativity.

Vocoder processing has been long used in many studies to examine how acoustic cues affect speech understanding and auditory processing. Early behavioral studies have shown that the type of carrier (i.e., pure-tone or noise) used in vocoding process affected the intelligibility of the perceived speech, and tone-vocoded stimuli had a perceptual advantage over noise-vocoded stimuli. This work further assessed whether the auditory evoked cortical response could objectively measure the perceptual difference between the two types of vocoded stimuli using an oddball-paradigm based event-related potential (ERP) experiment. A vowel stimulus was processed by noise- and tone-vocoding processes, and the processed stimuli were presented to normal-hearing listeners in an ERP experiment. The noise-vocoded and tone-vocoded vowel stimuli served as the deviant stimuli and the non-vocoded vowel stimulus as the standard stimulus. Experimental results showed that tone-vocoded stimulus evoked a significantly larger mismatch negativity (MMN) amplitude and a significantly shorter MMN peak latency than noise-vocoded stimulus did. Results in this work suggested that compared to noise-vocoded stimulus, tone-vocoded stimulus had a larger perceptual difference relative to the reference stimulus, and this effect caused by the usage of different carrier signals could be reflected by the MMN response.

An ERP Study on the Combined-stimulation Advantage in Vocoder Simulations.

Electric hearing is presently the only treatment solution for patients with profound-to-severe hearing loss. For those patients also preserving low-frequency residual hearing on the ipsilateral ear, combined electric-and-acoustic stimulation (EAS) could notably improve their speech understanding abilities relative to those aided with electric-only (E-only) hearing. Early behavioral studies have consistently shown the advantage of combined stimulation. The aim of this work was to objectively examine the advantage of combined stimulation over electric-only hearing using an oddballparadigm based event-related potential (ERP) experiment. The vowel stimulus was processed by vocoding processes simulating the E-only and EAS conditions, and the generated stimuli were presented to normal-hearing listeners in the ERP experiment. Experiment results showed that the mismatch negativity (MMN) response elicited in the combined-stimulation condition featured a smaller peak amplitude and a more delayed peak latency than that in the E-only condition. The MMN results in this work demonstrated that compared with the ERP response elicited in the E-only condition, the response in the combinedstimulation condition was much closer to that elicited by the full-spectrum stimulus, yielding neurophysiological evidence on the combined-stimulation advantage.