SREBP1 promotes 5-FU resistance in colorectal cancer cells by inhibiting the expression of caspase7

BACKGROUND

The role of lipid metabolism played in cancer cell growth attracts more attention. SREBP1 is a common lipid regulatory factor. It has been reported that SREBP1 can promote tumor cell resistance. The aim of this study was to investigate its role in chemoresistance of colorectal cancer (CRC).

METHODS

The expression of SREBP1 in CRC tissues was analyzed by immunohistochemistry. Using a viability assay, the sensitivity to 5-fluorouracil in two colon cancer cell lines (HT-29 and SW620) was measured and its correlation with different expression levels of SREBP1 protein by western blot was investigated.

RESULTS

The protein expression of SREBP1 in CRC tissues was higher than that in normal colon tissues. We found that over-expression of SREBP1 through SREBP1 gene transfection enhances the resistant of CRC cell lines to 5-FU, and SREBP1 silencing through SREBP1 shRNA transfection can promote apoptosis in 5-FU treated SW620 cells. Further study indicated that SREBP1 could inhibit the expression of caspase7 and reduce PARP1 cleavage fragments.

CONCLUSION

Our results suggest that SREBP1 protect the 5-FU treated CRC cells through caspase7 dependent PARP1 cleavage in apoptosis pathway and potentially provide a new target in the treatment of CRC.

[Using peripheral perfusion index and venous-to-arterial CO(2) difference/arterial-central venous O(2) difference ratio to assess lactate clearance in septic patients after resuscitation]

Objective: The relationship of venous-to-arterial CO(2) difference(Pv-aCO(2))/arterial-central venous O(2) difference (Ca-vO(2)) ratio, peripheral perfusion index(PI) and lactate clearance(LC) were investigated during resuscitation in septic patients. And, the meaning of the combination PI and Pv-aCO(2)/Ca-vO(2) ratio to interpret incoherence of lactate clear was explored. Methods: The patients with sepsis were prospectively observed, who admitted to critically care medicine department of Peking Union Medical College Hospital. The hemodynamic parameters, simultaneous arterial and central venous blood gas analysis and PI were obtained at the enrollment (T0) and 8 hours (T8) during resuscitation. The lactate clearance was defined as 8h-LC≥10% and non-lactate clearance was defined as 8h-LC ≤ 10%. Additionally, the patients were divided as three sub-groups according to the PI value at T8: the normalized PI group with PI≥1.4,the mild impaired PI with 1.4<PI<0.6 and severe impaired PI with PI≤0.6. Results: A total of 84 patients were enrolled in this study. There was no significant difference in Pv-aCO(2)/Ca-vO(2) ratio in the three groups. However, the PI≤0.6 group had a significantly higher Pv-aCO(2) than other groups. Moreover, the patients with non-lactate clearance (13/32) had a higher Pv-aCO(2)/Ca-vO(2) ratio than the patients with lactate clearance in PI≥1.4 group (1.9±0.7 vs. 1.3±1.0, P=0.01). Multivariate analysis showed both Pv-aCO(2)/Ca-vO(2) ratio [Exp(B) 2.235, 95% CI 1.232-4.055, P=0.008] and acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) [Exp (B) 1.087, 95%CI 1.022-1.156, P=0.008] were independent risk factor of non-lactate clearance. 8h-PI was significantly negative correlated with the 8 h Pv-aCO(2) gap (r=-0.311, P=0.004), but not significantly with Pv-aCO(2)/Ca-vO(2) ratio (r=-0.094, P=0.385). Conclusions: Both high Pv-aCO(2)/Ca-vO(2) ratio and low PI were related to non-lactate clearance after resuscitation in sepsis. Combined PI and Pv-aCO(2)/Ca-vO(2) ratio could interpret incoherence of latacte clearance after resuscitation.

Body mass index and the risk of mortality among Chinese adults with Type 2 diabetes

AIMS

To examine the associations between BMI and the risks of all-cause, cardiovascular disease (CVD)-specific and cancer-specific mortality among people with Type 2 diabetes, and thus provide recommendations for weight management in the population.

METHODS

This retrospective cohort study was conducted among 52 763 people with newly diagnosed Type 2 diabetes between 1 January 2004 and 31 December 2014 in Shanghai, China. All cases of death were identified by linking to the Shanghai Vital Statistics. Some 52 488 people were included in the analysis. Survival curves for people with different BMI categories were plotted using the Kaplan-Meier method. Cox proportional hazard models within or without restricted cubic spline functions were applied to examine the potential non-linear or linear relationship between BMI and the risk of mortalities respectively.

RESULTS

A total of 4777 deaths were identified during an average of 6-year follow-up. An L-shaped association was observed between BMI and all-cause mortality in men (P for overall association < 0.001 and P for non-linearity < 0.001) while a U-shaped association was found in women (P for overall association < 0.001 and P for non-linearity< 0.001). In men, no significant association was observed for BMI with cancer-specific and CVD-specific mortality. In women, an increased risk of cancer-specific mortality was observed with increasing BMI, whereas decreasing BMI was associated with the increased CVD-specific mortality rate.

CONCLUSION

The increased all-cause mortality in men with low BMI and in women with either low or high BMI indicate the importance of keeping BMI in a normal range for Chinese adults with Type 2 diabetes.

Abstract P1-13-03: Effects of neratinib after trastuzumab-based adjuvant therapy in hormone receptor-positive HER2+ early-stage breast cancer: Exploratory analyses from the phase III ExteNET trial

Background: The international, randomized, placebo-controlled phase III ExteNET trial showed that a 1-year course of neratinib after trastuzumab-based adjuvant therapy significantly improved 2-year invasive disease-free survival (iDFS) in patients with early-stage HER2+ breast cancer (BC) (hazard ratio 0.67; 95% CI 0.50–0.91; p=0.009) [Chan et al. Lancet Oncol 2016]. The significant iDFS benefit with neratinib was maintained after a median 5 years' follow-up (hazard ratio 0.73; 95% CI 0.57-0.92; p=0.008) [Martin et al. ESMO 2017]. At both time-points, marked benefit with neratinib was evident in patients with hormone receptor (HR)+ tumors, whereas in patients with HR– disease, initial improvements with neratinib diminished after completing treatment. We report exploratory analyses from the ExteNET trial done to better characterize the effects of neratinib in the HR+ subgroup.

Methods: Patients with early-stage HER2+ BC were randomly assigned to oral neratinib 240 mg/day or placebo for 1 year after standard primary therapy and trastuzumab-based adjuvant therapy. Randomization was stratified by HR status (locally assessed), nodal status, and trastuzumab regimen. Adjuvant endocrine therapy was recommended for patients with HR+ disease. Data concerning disease recurrences were collected prospectively during year 1-2 post-randomization, and from medical records during year 3–5 post-randomization. Primary endpoint: iDFS. Secondary endpoints: DFS including ductal carcinoma in situ (DFS-DCIS); time to distant recurrence (TTDR); distant DFS (DDFS); cumulative incidence of central nervous system (CNS) recurrences; overall survival (OS). Hazard ratios (95% CI) were estimated using Cox proportional-hazards models. Data cut-off: March 2017. Clinicaltrials.gov: NCT00878709.

Results: 2840 patients were randomized (neratinib, n=1420; placebo, n=1420); 1631 (57%) patients had HR+ tumors (neratinib, n=816; placebo, n=815). 93% and 94% of HR+ patients in the neratinib and placebo groups, respectively, were receiving adjuvant endocrine therapy at baseline. Efficacy outcomes in the HR+ cohort after a median follow-up of 5.2 years are shown in the table. In subgroup analyses of the HR+ cohort, hazard ratios for iDFS were 0.49 in centrally confirmed HER2+ patients (n=951), and 0.58 in patients who had completed prior trastuzumab ≤12 months before randomization (n=1334). CNS recurrence and OS data are not yet mature.

 Updated 2-year analysis5-year analysis  Hazard ratiobP-value Hazard ratiobP-value Δ, %a(95% CI)(2 sided)Δ, %a(95% CI)(2 sided)iDFS4.10.49 (0.31–0.75)0.0014.40.60 (0.43–0.83)0.002DFS-DCIS4.80.45 (0.29–0.69)&lt;0.0015.10.57 (0.42–0.79)&lt;0.001DDFS3.10.52 (0.32–0.84)0.0084.00.60 (0.42–0.85)0.004TTDR2.90.52 (0.31–0.85)0.013.80.61 (0.42–0.86)0.006a. Difference in event rates between neratinib vs placebo; b. Neratinib vs placebo

Conclusions: Neratinib was associated with an absolute iDFS benefit of 4.4% in patients with HR+/HER2+ BC after 5 years' follow-up. HR/HER2 receptor cross-talk may underpin the notable effect of neratinib in patients with HR+ tumors when given in combination with endocrine therapy.

Citation Format: Chia SKL, Martin M, Iwata H, Moy B, Lalani AS, Holmes FA, Mansi J, von Minckwitz G, Buyse M, Delaloge S, Ejlertsen B, Yao B, Murias Rosales A, Hellerstedt B, Cold S, Inoue K, Shen Z-Z, Galeano T, Barrios CH, Chan A. Effects of neratinib after trastuzumab-based adjuvant therapy in hormone receptor-positive HER2+ early-stage breast cancer: Exploratory analyses from the phase III ExteNET trial [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-13-03.

Diagnostic performance of cytology for assessment of hepatic lipid content in dairy cattle

The objective of our study was to characterize the diagnostic performance of cytology for assessing hepatic lipid content (HLC) in dairy cows by comparing microscopic evaluation of lipid vacuolation in touch imprint slide preparations of liver biopsies with quantitative measurement of triglyceride concentration ([TG]; mg/mg of wet weight) in paired biopsy samples. Our study also sought to compare the diagnostic performance of liver cytology, plasma nonesterified fatty acid concentration ([NEFA]), and plasma β-hydroxybutyrate concentration ([BHB]) derived from a measurement performed on whole blood, for assessing HLC. Chemical extraction of TG from liver tissue remains the gold standard for quantifying HLC, largely because available blood tests, although useful for detecting some types of pathology, such as increased lipid mobilization, ketosis, or hepatocellular injury, are nonspecific as to etiology. Veterinary practitioners can sample bovine liver for cytological evaluation in a fast, minimally invasive, and inexpensive manner. Thus, if highly predictive of HLC, cytology would be a practical diagnostic tool for dairy veterinarians. In our study, liver biopsy samples from Holstein cows (219 samples from 105 cows: 52 from cows 2 to 20 d prepartum, 105 from cows 0 to 10 d in milk, 62 from cows 18 to 25 d in milk) were used to prepare cytology slides and to quantify [TG] using the Folch extraction method followed by the Hantzch condensation reaction and spectrophotometric measurement. An ordinal scale (0-4) based on amount of hepatocellular cytoplasm occupied by discrete clear vacuoles was used by 3 blinded, independent observers to rank HLC in Wright-Giemsa-stained slides. Interobserver agreement in cytology scoring was good. Corresponding plasma [NEFA] and [BHB] measurements were available for 187 and 195 of the 219 samples, respectively. Liver [TG] correlated more strongly with cytology score than with NEFA or BHB, and receiver operating characteristic curve analysis showed that cytology had better diagnostic performance than either NEFA or BHB for correctly categorizing [TG] at thresholds of 5, 10, and 15%. Hepatic lipidosis in high-producing dairy cows is of major clinical and economic importance, and this study demonstrates that cytology is an accurate means of assessing HLC. Additional work is indicated to evaluate the diagnostic utility of liver cytology.

Radiation pneumonitis in non-small-cell lung cancer patients treated with helical tomotherapy

OBJECTIVE

In this study, we investigated the incidence of radiation pneumonitis (RP) in non-small-cell lung cancer (NSCLC) patients undergoing helical tomotherapy (HT) and the clinical and dosimetric factors associated with it.

MATERIALS AND METHODS

We analyzed data from the treatment protocols of 62 NSCLC patients. The median total radiation dose was 64 Gy (range 57.6-66 Gy) at 1.8-2.2 Gy/fraction. Thirty-four of these patients underwent HT alone and 28 underwent HT in combination with chemotherapy. Treatment-related pneumonitis was graded according to the Common Terminology Criteria for Adverse Events, version 3.0.

RESULTS

We found that RP grades 1, 2, 3 and 5 occurred in 29 (46.8%), 23 (37.1%), 8 (12.9%), and 2 (3.2%) patients, respectively. Using univariate analyses, we found that a grade ≥3 RP was associated with poor performance status (PS), age, planning target volume, mean lung dose, and relative V5through V25, in increments of 5 Gy (P < 0.005). We determined that PS and V5V15were the most significant factors associated with grade ≥3 RP using multivariate analysis.

CONCLUSIONS

We found that poor PS and V5-V15 were the risk factors associated with grade ≥3 RP in NSCLC patients treated with HT. Thus, for NSCLC patients treated with HT, the volume of total lung with low-dose region (V5-V15) should be carefully regulated and the use of HT should be restricted in patients with Eastern Cooperative Oncology Group ≥2.

[Insulin regimes and impact on glycemic control in patients with type 1 diabetes]

Objective: To describe the insulin regimens and their associations with glycemic control and to explore factors associated with intensive insulin therapy. Methods: Patients with type 1 diabetes (T1DM) were recruited from Guangdong Type 1 Diabetes Mellitus Translational Medicine Study which was conducted in 16 centers in Guangdong province. The demographic and clinical data were collected. Patients were grouped according to different insulin regimens: insulin pump (R1), basal insulin plus regular insulin or short-acting insulin (R2), insulin injection 1-3 times per day (R3). Distribution of insulin regimens and the relationships between insulin regimens and hemoglobin A1c (HbA1c) were described. Multivariate logistic regression was used to identify factors associated with intensive insulin therapy. Results: A total of 1 421 patients with the age of 27.8 (19.4, 38.3) years and a duration of T1DM of 3.3 (0.5, 7.1) years were recruited. There was 12.3% of patients in R1 (n=175), 35.5% in R2 (n=504), and 52.2% in R3 (n=742), respectively. HbA1c was 8.0 (6.8, 9.3)%, 8.9 (7.1, 11.8)%, and 9.2 (7.5, 11.4)% in R1, R2, R3, respectively, and it was associated with insulin regimens (P<0.001). HbA1c target rate was 32.3%, 21.1%, 17.8% in R1, R2, R3, respectively (P=0.002). Older age (OR=1.01, P=0.027), higher education level (college or above) (OR=1.56, P=0.003), and higher household income (>30 000 yuan per year per person)(OR=1.45, P=0.009) were associated with intensive insulin therapy in adult patients. Conclusions: The study suggested that insulin therapy need to be optimized in patients with T1DM. The optimization of insulin regimens and diabetes education may be helpful for improvement of glycemic control.

[Study on sweat gland regeneration induced by microenvironment of three-dimensional bioprinting]

Sweat glands are abundant in the body surface and essential for thermoregulation. Sweat glands fail to conduct self-repair in patients with large area of burn and trauma, and the body temperature of patients increases in hot climate, which may cause shock or even death. Now, co-culture system, reprogramming, and tissue engineering have made progresses in inducing sweat gland regeneration, but the inductive efficiency and duration need to be improved. Cellular microenvironment can regulate cell biological behavior, including cell migration and cell differentiation. This article reviews the studies of establishment of microenvironment in vitro by three-dimensional bioprinting technology to induce sweat gland regeneration.

Wax: A benign hydrogen-storage material that rapidly releases H2-rich gases through microwave-assisted catalytic decomposition

Hydrogen is often described as the fuel of the future, especially for application in hydrogen powered fuel-cell vehicles (HFCV's). However, its widespread implementation in this role has been thwarted by the lack of a lightweight, safe, on-board hydrogen storage material. Here we show that benign, readily-available hydrocarbon wax is capable of rapidly releasing large amounts of hydrogen through microwave-assisted catalytic decomposition. This discovery offers a new material and system for safe and efficient hydrogen storage and could facilitate its application in a HFCV. Importantly, hydrogen storage materials made of wax can be manufactured through completely sustainable processes utilizing biomass or other renewable feedstocks.

Catalytic dehydrogenation of propane by carbon dioxide: a medium-temperature thermochemical process for carbon dioxide utilisation

The dehydrogenation of C₃H₈ in the presence of CO₂ is an attractive catalytic route for C₃H₆ production. In studying the various possibilities to utilise CO₂ to convert hydrocarbons using the sustainable energy source of solar thermal energy, thermodynamic calculations were carried out for the dehydrogenation of C₃H₈ using CO₂for the process operating in the temperature range of 300–500 °C. Importantly, the results highlight the enhanced potential of C₃H₈ as compared to its lighter and heavier homologues (C₂H₆ and C₄H₁₀, respectively). To be utilised in this CO₂ utilisation reaction the Gibbs free energy (Δ_rGθm) of each reaction in the modelled, complete reacting system of the dehydrogenation of C₃H₈ in the presence of CO₂ also indicate that further cracking of C₃H₆ will affect the ultimate yield and selectivity of the final products. In a parallel experimental study, catalytic tests of the dehydrogenation of C₃H₈ in the presence of CO₂ over 5 wt%-Cr₂O₃/ZrO₂ catalysts operating at 500 °C, atmospheric pressure, and for various C₃H₈ partial pressures and various overall GHSV (Gas Hourly Space Velocity) values. The results showed that an increase in the C₃H₈ partial pressure produced an inhibition of C₃H₈ conversion but, importantly, a promising enhancement of C₃H₆ selectivity. This phenomenon can be attributed to competitive adsorption on the catalyst between the generated C₃H₆ and inactivated C₃H₈, which inhibits any further cracking effect on C₃H₆ to produce by-products. As a comparison, the increase of the overall GHSV can also decrease the C₃H₈ conversion to a similar extent, but the further cracking of C₃H₆ cannot be limited.

Genetic diversity and expression profiles of cysteine phytases in the sheep rumen during a feeding cycle

Cysteine phytase is the main phytate-degrading enzyme of ruminant animals. To explore the genetic diversity and dynamic expression profile of cysteine phytase in sheep rumen during a feeding cycle, four transcript (0, 4, 9 and 16 h after feeding) and one DNA (9 h after feeding) clone libraries were constructed, respectively. A total of 46 distinct gene fragments were identified, and most of these sequences had low identities (<60%) with known phytases. Great divergence was found in the constitution and abundance of genes at the genome and transcriptional levels, and the transcript data are more reliable to reflect the information of functional genes. Phylogenetic analysis indicated that the genes from uncultured bacteria instead of Firmicutes played the major phytate-degrading role. Further comparative analysis revealed the dynamic constitution of cysteine phytase genes in rumen at different time points.

SIGNIFICANCE AND IMPACT OF THE STUDY

Ruminal phytases, that are cysteine phytases, are novel in sequences and functions. Great divergence in the constitution and abundance of cysteine phytase genes at the genome and transcriptional levels suggested that transcript data are more reliable to reflect the information of functional genes. Phylogenetic and rarefaction analyses indicated that the cysteine phytase genes from uncultured bacteria instead of Firmicutes play the major phytate-degrading role in rumen, and their constitution is dynamic at different time points. This study provides a new insight into ruminal cysteine phytase genes and undermines their expression profiles over a whole feeding cycle.

Phase III study (MONET1) of motesanib plus carboplatin/paclitaxel in patients with advanced nonsquamous nonsmall-cell lung cancer (NSCLC): Asian subgroup analysis

BACKGROUND

This preplanned subset analysis of the phase III MONET1 study aimed to determine whether motesanib combined with carboplatin/paclitaxel (C/P) would result in improved overall survival (OS) versus chemotherapy alone, in a subset of Asian patients with nonsquamous nonsmall-cell lung cancer (NSCLC).

PATIENTS AND METHODS

Patients with nonsquamous NSCLC (stage IIIB/IV or recurrent) and no prior systemic therapy for advanced disease were randomized to IV carboplatin (AUC, 6 mg/ml min) and paclitaxel (200 mg/m2) for up to six 3-week cycles, plus either oral motesanib 125 mg q.d. or placebo. Primary end point was OS; secondary end points included progression-free survival (PFS), objective response rate (ORR), and safety.

RESULTS

Two hundred twenty-seven Asian patients from MONET1 were included in this descriptive analysis. Median OS was 20.9 months in the motesanib plus C/P arm and 14.5 months in the placebo plus C/P arm (P=0.0223); median PFS was 7.0 and 5.3 months, respectively, (P=0.0004); and ORR was 62% and 27%, respectively, (P<0.0001). Grade≥3 adverse events were more common in the motesanib plus C/P arm versus placebo plus C/P (79% versus 61%).

CONCLUSION

In this preplanned subset analysis of Asian patients with nonsquamous NSCLC, motesanib plus C/P significantly improved OS, PFS, and ORR versus placebo plus C/P.

CLINICAL TRIAL NUMBER

NCT00460317.