Downregulation of kynureninase restrains cutaneous squamous cell carcinoma proliferation and represses the PI3K/AKT pathway

BACKGROUND

The protein kynureninase (KYNU) has recently been reported to participate in the pathological processes of various diseases.

AIM

To explore the expression and the biological function of KYNU in cutaneous squamous cell carcinoma (cSCC).

METHODS

Expression of KYNU in cSCC cell lines and tissues was firstly evaluated based on the Gene Expression Omnibus and the Oncomine databases. Quantitative reverse transcription-PCR was performed to determine the mRNA expression of KYNU in cSCC cell lines. Small interfering RNA (siRNA) was used for silencing KYNU. The effect of KYNU on the growth and motility of cSCC cells was determined by cell counting kit-8, wound-healing and Transwell assays, and western blotting was used to determine the protein expression of KYNU, AKT, phosphoinositide 3-kinase (PI3K), phosphorylated (p)-AKT and p-PI3K.

RESULTS

KYNU was significantly upregulated in cSCC tissues and cell lines. Knockdown of KYNU using siRNA noticeably suppressed the proliferation, migration and invasion ability of SCL-1 cells (P < 0.01). Western blotting revealed that phosphorylation of AKT and PI3K was markedly inhibited after silencing KYNU. The ratios of p-AKT/AKT and p-PI3K/PI3K were significantly decreased in the si-KYNU group compared with the control group.

CONCLUSION

Depletion of KYNU could inhibit the growth of cSCC cells, possibly through modulating PI3K/AKT pathway. These data indicate that KYNU takes a key part in the malignant progression of cSCC, and could be considered as a promising therapeutic target for cSCC treatment.

Molecular cloning, characterisation, and expression analysis of adipocyte fatty acid binding protein gene in Xupu goose (Anser cygnoides domesticus)

1. Adipocyte fatty acid binding protein (A-FABP) plays a key role in fatty acid uptake and intracellular transport. The objective of the present study was to identify and characterise the A-FABP gene in Xupu goose.2. The full-length cDNA of goose A-FABP gene was cloned from the liver tissue using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The distribution of the goose A-FABP in different tissues was determined by quantitative real-time PCR (qRT-PCR).3. The results showed that the full-length cDNA sequence of goose A-FABP was 657 bp, containing a 5'-UTR of 52 bp, a 3'-UTR of 206 bp and an open reading frame (ORF) of 399 bp, which encoded a polypeptide of 132 amino acids (AA).4. The AA sequence of goose A-FABP showed 76.52%, 75.00%, 93.18% and 99.24% identities with previously described homologues from humans (Homo sapiens), mouse (Mus musculus), chicken (Gallus gallus), and duck (Anas platyrhynchos), respectively, and phylogenetic analysis revealed a close relationship among them. The transcript of Xupu goose A-FABP was ubiquitously expressed in all tested tissues, and showed a high-level expression in abdominal fat, sebum and liver.5. A significant positive correlation was identified between A-FABP mRNA abundance in the three adipose tissues and liver weight, ratio of liver to body weight, TG content, and VLDL concentration in the plasma of Xupu goose. A significant negative correlation was observed between the mRNA level of A-FABP and HDL concentration in the plasma of Xupu goose.6. These findings provide a foundation for further research on the function and mechanism of A-FABP in the fat deposition process.

The oncological outcome and influence of neoadjuvant chemotherapy on the surgery in the resectable and locally advanced oral squamous cell carcinoma

Aim

The role of neoadjuvant chemotherapy (NCT) in the treatment of advanced oral squamous cell carcinoma (OSCC) is still controversial. Especially, there are still few studies investigating the influence of NCT on the following surgery. In this retrospective single-center attended cohort study, we investigated the oncological effect of NCT and its influence on the following surgery in patients with resectable locally advanced OSCC.

Method

The clinical data of 88 patients with locally advanced but resectable OSCC (T3/4) were reviewed retrospectively. NCT plus conservative surgery and radical surgery were compared. Five-year disease-specific survival (DSS) was observed as the main endpoint.

Results

Among 88 patients enrolled in this study, 56 patients received upfront radical surgery (non-NCT group) and 32 patients received NCT followed by surgery (NCT group). The patients in the non-NCT group had a statistically better DSS than the patients in the NCT group (P=0.041). Twenty-one out of 32 (65.6%) patients who received NCT were good responders including two patients (6.2%) had a complete response and 19 patients (59.4%) had a partial response. There was no statistical difference between good and poor responders in 5-year DSS (P=0.823). Eleven patients (34.4%) had conservative surgery without flap reconstruction and 21 patients had radical surgery with flap reconstruction after NCT. No statistical difference in surgical margins was found between the two types of surgery (P=0.519). There was also no statistical difference in 5-year DSS between the two types of surgery (P=0.652).

Conclusion

NCT plus surgery could not improve survival compared with upfront surgery. NCT could modify the surgical extent but would not affect the surgical margins. This conclusion should be explained cautiously, and randomized clinical trials with large sample size were needed to further answer the question.

Comprehensive analysis of EGFR T790M detection by ddPCR and ARMS-PCR and the effect of mutant abundance on the efficacy of osimertinib in NSCLC patients

Background

Patients with non-small cell lung cancer (NSCLC) harboring epidermal growth factor receptor (EGFR) mutations often develop systemic disease progression during treatment with EGFR-tyrosine kinase inhibitors (TKIs). Droplet digital polymerase chain reaction (ddPCR) and amplification refractory mutation system (ARMS)-PCR are routinely applied for detection of EGFR mutations, including T790M, which is associated with TKI sensitivity. We compared the efficiency of ddPCR and ARMS-PCR in detecting T790M and explored the association between T790M abundance and osimertinib efficacy.

Methods

Genomic DNA (gDNA) from tissue and cells in hydrothorax and circulating tumor DNA (ctDNA) from peripheral blood (PB), and clinicopathological data were retrospectively collected from 263 patients who visited Sun Yat-sen University Cancer Center for T790M test.

Results

Mean T790M abundance and mutant copy number of cases tested positive by both methods, i.e., the ddPCR+ARMS+ group (19.1%, 636.9), were higher than those in the ddPCR+ARMS- group (0.36%, 12.1), suggesting that ddPCR is more sensitive in detecting samples with low mutant abundance than ARMS-PCR. T790M detection rate was comparable for gDNA and ctDNA samples (44.7% vs. 37.6%, P=0.242); however, gDNA sample tended to show more T790M abundance in ddPCR analysis. T790M coexisted with L858R mutation (8/11) more than with deletions in exon 19 (19del) mutation (3/11) in TKI-naive tumors, while 19del co-occurred as often as L858R in post-TKI tumors. T790M+ patients benefited more from osimertinib and showed longer progression-free survival (PFS) (not achieved vs. 10.1 months, P=0.0399), while lower T790M abundance (<1.065%) was associated with longer PFS (not achieved vs. 8.8 months, P=0.0033).

Conclusions

ddPCR has a higher sensitivity than ARMS-PCR, especially in detecting the less abundant T790M. Although detection rates were comparable for ctDNA and gDNA samples, the mutation abundance was higher in gDNA sample. Finally, low T790M abundance was associated with longer PFS in NSCLC patients receiving osimertinib treatment.

Type-II InSe/ g-C3N4 Heterostructure as a High-Efficiency Oxygen Evolution Reaction Catalyst for Photoelectrochemical Water Splitting

We propose a conceptual design of InSe/ g-C₃N₄ van der Waals heterostructure to achieve highly efficient and spontaneous water splitting. InSe/ g-C₃N₄ possesses a direct band gap of 2.04 eV with type-II band alignment, which is beneficial to the separation of electrons and holes and exhibits proper valence and conduction-band positions for the redox reactions of H₂O. In addition, the adsorption of multiple water molecules and the changes of free energy on InSe/ g-C₃N₄ have been calculated to understand the oxygen evolution reaction (OER) process of water splitting. The free energies of reaction on three sides are all downhill, and the values of Δ G reduce to about -0.406 eV, indicating that the OER of water splitting is a thermodynamically permissible reaction without the aid of any other substance. Therefore, the water-splitting reaction could be thermodynamically continued using InSe/ g-C₃N₄ as a photocatalyst, which indicates that InSe/ g-C₃N₄ is an excellent candidate for photocatalyst or photoelectronic applications.

Genome-wide association study identified genes in the response to Salmonella pullorum infection in chickens

Pullorum is a bacterial disease that threatens the modern poultry industry. Over the years, research on this topic has focused mainly on its epidemiology, whereas the hosts' genetic basis of infection is still vague. In order to identify chickens' genes associated with pullorum, we sequenced 300 New Pudong chicken by double digest genotyping-by-sequencing. We obtained 1 527 953 SNPs for a genome-wide association analysis, which identified 43 genome-wide significant markers. Most of the significant SNPs were in the interval of 57.7-59.0 Mb on chromosome 5. The gene set enrichment analysis suggests a potential manner for bacterial infection and remaining inside the host. This work provides basic data for the purification, prevention and treatment of pullorum disease.

[Inhibitory Eefects of the novel tyrosine kinase inhibitor BGJ398 against human leukemic cell line KG-1 cells]

目的

探讨针对FGFR1的酪氨酸激酶抑制剂BGJ398对人急性髓系白血病细胞株KG-1细胞的影响及可能的作用机制。

方法

CCK-8法检测BGJ398对KG-1细胞增殖的影响；流式细胞术Annexin Ⅴ/PI双重染色法检测BGJ398对细胞凋亡的影响；RQ-PCR检测细胞凋亡相关基因的表达；Western blot法检测凋亡相关蛋白、FGFR1OP2-FGFR1融合蛋白及信号通路分子磷酸化水平的表达变化。

结果

BGJ398能有效抑制KG-1细胞增殖，抑制率呈剂量依赖性升高，并能诱导细胞凋亡。BGJ398作用KG-1细胞48 h后，与对照组比较凋亡相关基因Bcl-2表达下降（0.342±0.054对1.026±0.165，t=3.94，P=0.017），caspase-3表达上调（0.456±0.189对1.008±0.091，t=16.44，P<0.001），差异均有统计学意义。与对照组相比，BGJ398作用组caspase-3活化蛋白表达增加，同时Bcl-2蛋白表达下调；FGFR1OP2-FGFR1融合蛋白水平及AKT、S6K1磷酸化水平下调，差异均有统计学意义（P值均<0.01），但ERK磷酸化表达水平无明显改变。

结论

BGJ398能有效抑制KG-1细胞增殖并诱导细胞凋亡，其机制可能与抑制FGFR1表达、下调Bcl-2水平、促进Caspase-3活化及抑制AKT和S6K磷酸化有关。

Abstract P1-09-15: DNA methylation markers influenced by BMI are associated with breast cancer

Body mass index (BMI) is a well-established risk factor for breast cancer. However, the underlying molecular mechanism through which BMI acts on breast cancer remain largely unknown. DNA methylation plays a critical role in regulating gene expression. Aberrant DNA methylation has been implicated in breast cancer development. We hypothesize that BMI influences DNA methylation that in turn leads to breast cancer. We therefore conducted a molecular epidemiological study to identify DNA methylation markers that are associated with BMI in healthy women and further determine the association of these DNA methylation changes with breast cancer development and occurrence. We analyzed 270 normal breast tissue from healthy women and 109 tumor tissue from breast cancer patients for genome-wide DNA methylation profiling using the Illumina Truseq® Methyl Capture EPIC sequencing technology. After data quality control, approximately 3 million CpG sites (sequencing depth≥10) were retained and included in further statistical analysis. Linear regression was performed to examine the association between BMI and each of CpG sites, adjusting for age and race. Bonferroni correction was used for control for multiple comparisons. We further investigated whether these BMI-associated DNA methylation markers were differentially methylated in normal and breast tissue. We found that 30 CpG sites were significantly associated with BMI (P&lt; 1.5x 10-8) in normal breast tissue. Many of these GpG sites were also differentially methylated in tumor and normal breast tissue. Top CpG hits are near novel and putative cancer genes mainly involved in lipid metabolism and related reproductive phenotypes that increase breast cancer risk, including KIAA0232, SHZ2, LACTB, PAPPA, and DLGAP2. The most significant CpG site associated with BMI is on chr. 4 in KIAA0232 gene. Little is known about the function of this gene, but genetic variant near the gene are associated with platelet count and volume in GWAS. The second most significant hit is on chr.20 in gene TSHZ2. This gene is found downregulated in breast and prostate cancer. LACTB gene is a tumor suppressor that modulates lipid metabolism and cell state. Its mechanism of action involves alteration of mitochondrial lipid metabolism and differentiation of breast cancer cells. PAPPA gene plays a role in inflammation and promote invasion of cancer cells. DLGAP2 is an imprinted gene, and SNPs near DLGAP2 are associated with age at menarche in AA women. Our results suggest DNA methylation may intermediate the observed association between BMI and breast cancer. Further research is warranted to validate these findings in larger studies as well as to understand the regulatory network by linking data with gene expression.

Citation Format: He C, Lin N, Castle J, Liu J, Liu Y, Wang C. DNA methylation markers influenced by BMI are associated with breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-09-15.

Pulsed electromagnetic fields: promising treatment for osteoporosis

Osteoporosis (OP) is considered to be a well-defined disease which results in high morbidity and mortality. In patients diagnosed with OP, low bone mass and fragile bone strength have been demonstrated to significantly increase risk of fragility fractures. To date, various anabolic and antiresorptive therapies have been applied to maintain healthy bone mass and strength. Pulsed electromagnetic fields (PEMFs) are employed to treat patients suffering from delayed fracture healing and nonunions. Although PEMFs stimulate osteoblastogenesis, suppress osteoclastogenesis, and influence the activity of bone marrow mesenchymal stem cells (BMSCs) and osteocytes, ultimately leading to retention of bone mass and strength. However, whether PEMFs could be taken into clinical use to treat OP is still unknown. Furthermore, the deeper signaling pathways underlying the way in which PEMFs influence OP remain unclear.

Identification and characterization of circular RNAs during the sea buckthorn fruit development

As a rising star of noncoding RNA, circular RNAs (circRNAs) have a covalently closed loop structure, which formed by 3'-5' ligation during splicing. A few circRNAs were identified and thought to be transcriptional noise due to cognitive defect over the past 40 years. Recently, with the development of high-throughput RNA sequencing techniques and specific algorithms for circRNA detection and quantification, plenty of potential circRNAs were identified in many species which play important roles in various biological processes. However, researches on circRNAs in fruit ripening process were lacking. Here, we totally identified 2616 circRNAs in sea buckthorn fruit development process, which uniformly distributed in sea buckthorn chromosome. Among them, 1721 (65.8%) circRNAs were arising from the exons of their host genes, 252 circRNAs were identified as the differentially expressed circRNAs (DEcircRNAs) between three different development stages, and 181 (71.8%) DEcircRNAs had sequence similarity with 235 identified circRNAs from five know plant species. Functional annotation revealed that host genes of DEcircRNAs were predicted to be involved in carotenoid biosynthesis, lipid synthesis and plant hormone signal transduction. Additionally, 53 DEcircRNAs were predicted as the corresponding nine miRNAs sponges in sea buckthorn. Divergent reverse-transcription PCR and RT-qPCR were used for validate the differential expression and back-splicing sites of six DEcircRNAs. These results revealed the role of circRNAs in sea buckthorn fruit ripening process and promoted the noncoding RNA researches in plants.

A systematic review and quantitative assessment of methylation biomarkers in fecal DNA and colorectal cancer and its precursor, colorectal adenoma

Colorectal cancer (CRC) arises from accumulated genetic and epigenetic alterations, which provide the possibility to identify tumor-specific biomarkers by analyzing fecal DNA. Methylation status in human genes from tumor tissue is highlighted as promising biomarker in the early detection of CRC. A number of studies have documented altered methylation levels in DNA extracted from stool samples, but generated heterogeneous results. We performed a systematic review and quantitative assessment of existing studies to compare levels of DNA methylation in most frequently studied genes and their diagnostic value in CRC and its precursor, colorectal adenoma, with their counterparts in healthy subjects. Robust searches of the literature were performed in our study with explicit strategies and definite inclusion/exclusion criteria. Pooled data revealed that methylation levels of SFRP2, SFRP1, TFPI2, BMP3, NDRG4, SPG20, and BMP3 plus NDRG4 genes exceeded a sensitivity of 70% and a specificity of 80% for CRC detection. The DOR of the seven candidate biomarkers ranged from 19.80 to 334.33, indicating a good diagnostic power in discriminating cancer from normal tissues. The AUC range was from 0.88 to 0.95, indicating a good or very good discriminatory performance. When test results for BMP3 and NDRG4 were combined, the DOR of CRC detection was 98.36, which was higher than that for BMP3 and NDRG4 separately. As for adenoma detection, the DOR of methylated NDRG4 is higher than that for CRC (CRC vs. adenoma: 54.86 vs. 57.22). Both the sensitivity and specificity of NDRG4 for adenoma detection exceeded 70%. These findings demonstrate the eligibility and feasibility of DNA methylation as a minimally invasive biomarker in feces in the diagnosis of CRC and adenoma. The use of DNA from human stools has the potential to be readily applicable to detect aberrant DNA methylation levels among many subjects for CRC early screening.

Transcriptomic and functional analyses unveil the role of long non-coding RNAs in anthocyanin biosynthesis during sea buckthorn fruit ripening

Fruit ripening is a developmental process regulated by a complex network of endogenous and exogenous cues. Sea buckthorn is an excellent material for fruit ripening studies due to its dramatic ripening process and high contents of nutritional and anti-oxidant compounds in berries. Here, the whole transcriptome of sea buckthorn fruit at three development stages were analysed using multiple high-throughput sequencings. We assembled and annotated 9,008 long non-coding RNAs (lncRNAs) in sea buckthorn fruits, and identified 118 differentially expressed lncRNAs (DE-lncRNAs) and 32 differentially expressed microRNAs in fruit developmental process. In addition, we predicted 1,061 cis-regulated and 782 trans-regulated targets of DE-lncRNAs, and these DE-lncRNAs are specifically enriched in the biosynthesis of ascorbic acid, carotenoids and flavonoids. Moreover, the silencing of two lncRNAs (LNC1 and LNC2) in vivo and expression analysis revealed that LNC1 and LNC2 can act as endogenous target mimics of miR156a and miR828a to reduce SPL9 and induce MYB114 expression, respectively, which lead to increased and decreased anthocyanin content as revealed by high-performance liquid chromatography analysis. Our results present the first global functional analysis of lncRNA in sea buckthorn and provide two essential regulators of anthocyanin biosynthesis, which provides new insights into the regulation of fruit quality.

Size, Aspect Ratio and Anatomic Location of Ruptured Intracranial Aneurysms: Consecutive Series of 415 Patients from a Prospective, Multicenter, Observational Study

To analyze the size and location distribution of ruptured intracranial aneurysms (IAs) helps to provide evidence for clinical treatment of unruptured IAs using this feature of aneurysms. In this study, 415 patients who presented with an acute subarachnoid hemorrhage caused by IAs were enrolled from eight tertiary referral centers between June 2016 and March 2018. The size, aspect ratio and anatomic location of ruptured IAs were defined and reported by patient sex. In the study cohort of 415 patients (60.5% women) with saccular ruptured IAs, the three most common locations of ruptured IAs were posterior communicating artery (32.0%), anterior communicating artery (28.7%), and middle cerebral artery (13.5%). The mean size of all ruptured IAs was 5.3±3.1 mm (range 1.1-28.5 mm), but the size varied considerably by location. For example, ruptured IAs of the posterior communicating artery had a mean size of 5.8±3.1 mm, whereas the mean size of ruptured anterior communicating artery aneurysms was 4.6±1.7 mm. The mean AR in all ruptured IAs was 1.66±0.76. Of those aneurysms, 243 (58.6%) had an AR smaller than 1.6 and 318 (76.6%) had an AR smaller than 2.0. Our results suggested that the size of the most ruptured IAs are smaller than 7 mm or even 5 mm. The size and AR varied by sex and location. With the knowledge of size, location and AR, multiplicity should be considered for treatment strategies of unruptured IAs.

[The application of retroperitoneal laparoscopic nephron-sparing surgery in stage T(1b) renal cell carcinoma]

Objective: To investigate the safety and feasibility of retroperitoneal laparoscopic nephron-sparing surgery (NSS) in stage T(1b) renal cell carcinoma (RCC) patients . Methods: Between March 2014 and June 2017, 52 stage T(1b) RCC cases (36 males, 16 females) treated with retroperitoneal laparoscopic NSS in Zhongshan Hospital and Central Hospital of Minhang District were enrolled and retrospectively analyzed, with a tumor size range of 4.0 to 6.8 cm, and a mean size of(4.7±0.45)cm.The anatomic characteristics of tumors, operative time, intra-operative blood loss, warm ischemia time, intra- and post-operative complications, length of hospital stay, and oncological outcomes were reviewed. Results: Only 2 cases converted to open surgery due to uncontrollable bleeding in operation. The rest 50 cases successfully underwent retroperitoneal laparoscopic NSS, with mean operative time of (122±20.86) min (range: 100-220 min), mean blood loss of (140±128.85)ml (range: 50-800 ml), mean warm ischemia time of (30±3.52)min (range: 25-42 min), pre-operative mean serum creatinine of (100±23.54)μmol/L (range: 65-148 μmol/L), mean serum creatinine three monthsafter operation of (104±30.84)μmol/L (range: 72-224 μmol/L), mean drainage of (180±82.33)ml (range: 80-550 ml), mean length of hospital stay after operation of (8±1.56)d (range: 5-15 d). There was no significant difference in renal function between pre- and post-operation (P=0.056). One patient suffered pulmonary embolism was cured conservatively. Fifty patients were followed up, among which 47 cases with malignant pathology were followed up for 3-29 months, and two of them suffered from pulmonary metastasis. Conclusions: After pre-operative comprehensive assessment of tumors, stage T(1b) renal cell carcinoma could be treated with retroperitoneal laparoscopic NSS safely.