Triptolide induces mitochondrial apoptosis through modulating dual specificity phosphatase 1/mitogen-activated protein kinases cascade in osteosarcoma cells

Due to chemoresistance and metastasis, the overall prognosis of osteosarcoma (OS) has not improved over the last two decades. Exploring novel therapeutic agents that can circumvent theses malignant phenotypes of OS would be essential to improve the survival of OS patients. Triptolide is a unique diterpene triepoxide that possesses potent antitumor activities.However, the effects and mechanism of triptolide on OS cells remain unknown. The effects of triptolide on viability, apoptosis, cell cycle distribution and migratory ability of OS cells were measured using MTT, flow cytometry and wound healing and transwell invasion assays. And an OS tumor xenograft mouse model was produced to further study the in vivo antitumor effects of triptolide. The expression of DUSP1 at the protein and mRNA level in OS cells was detected by western blot and qPCR. We report that triptolide exhibits multidimensional antitumor activities in OS cells, including the induction of apoptosis and G1 phase accumulation, inhibition of cell viability, migration, and invasion. We further demonstrate that triptolide inhibits the expression of dual-specificity protein phosphatase1 (DUSP1) through inhibiting its promoter activity, which causes sustained activation of three subfamilies of mitogen-activated protein kinase (MAPK). And the modulation of DUSP1/MAPK cascade is associated with the apoptosis of OS cells, since the ectopic expression of DUSP1 or the inhibition of MAPK using specific inhibitors can counteract triptolide-induced apoptosis. In addition, triptolide enhances doxorubicin-induced apoptosis. In summary, our study suggests that DUSP1 is an important cellular target of triptolide, and triptolide may be a promising treatment option for OS as a single agent or combined with other chemotherapeutics.

PREGABALIN TREATMENT OF PERIPHERAL NERVE DAMAGE IN A MURINE DIABETIC PERIPHERAL NEUROPATHY MODEL

Context

Peripheral nerve lesions are a major complication of diabetes mellitus, the main clinical manifestations of which are numbness and pain involving the limbs.

Objective

To determine the correlation between pregabalin treatment and diabetic peripheral neuropathic pain.

Design

An experimental animal study in BALB/c mice.

Subjects and Methods

Diabetes models are established by injecting streptozotocin (STZ) into the abdominal cavities of mice. The correlation between the treatment effect, time, and dosage of pregabalin was determined. The effect of a type 1 organic cation transporter (Octn1) in the absorption of pregabalin was evaluated.

Results

Pregabalin reduced tactile allodynia in diabetic mice. The best analgesic effect occurred when intestinal absorption was increased. Octn1 mediated pregabalin entry into intestinal epithelial cells, which influenced the absorption of pregabalin with a time-dependent fluctuation in the small intestine. Peripheral nerve damage caused by diabetes was dependent on time and dose of pregabalin, which was related to the regular expression of Octn1 in small intestinal epithelium.

Conclusions

Peripheral nerve damage caused by diabetes was dependent on time and dosage of pregabalin, which was related to the regular expression of Octn1 in small intestinal epithelium.

[Application of dental floss traction-assisted endoscopic submucosa dissection to rectal neuroendocrine neoplasm]

Objective: To evaluate the safety and efficacy of dental floss traction-assisted endoscopic submucosal dissection (DFS-ESD) for rectal neuroendocrine neoplasm (NEN). Methods: A retrospective cohort study was performed. Clinical data of rectal NEN patients undergoing ESD at Endoscopy Center of Zhongshan Hospital, Fudan University from January 2016 to December 2017 were retrospectively analyzed. Inclusion criteria: 1) age of 18 to 80 years old; 2) maximal diameter of lesions <1.5 cm; 3) tumor locating in the submucosa without invasion into the muscularis propria; 4) no enlarged lymph nodes around bowel and in abdominal cavity; 5) ESD requested actively by patients. A total of 37 patients were enrolled, including 23 male and 14 female cases with mean age of (56.0±11.3) years. All the lesions were single tumor of stage T1, and the mean size was 0.8±0.2(0.5-1.2) cm. Postoperative pathology revealed all samples as neuroendocrine tumors (NET). Seventeen patients received DFS-ESD treatment (DFS-ESD group) and 20 patient received conventional ESD treatment (conventional ESD group). In DFS-ESD group, after the mucosa was partly incised along the marker dots, the endoscopy was extracted, and the dental floss was tied to one arm of the metallic clip. When the endoscope was reinserted, the hemoclip was attached onto the incised mucosa; another hemoclip was attached onto normal mucosa opposite to the lesion in the same way. The submucosa was clearly exposed with the traction of dental floss and the resection could proceed. The conventional ESD group received the traditional ESD operation procedure. The operation time, modified operation time (remaining time after excluding the assembly time of dental floss traction in DFS-ESD group), en bloc resection rate, R0 resection rate, morbidity of operative complication, recurrence and metastasis were compared between two groups. Results: The average tumor size was (0.8±0.2) cm in DFS-ESD group and (0.7±0.2) cm in conventional ESD group (t=0.425, P=0.673). According to postoperative pathological grading of rectal neuroendocrine neoplasm, 13 were G1 and 4 were G2 in DFS-ESD group, while 17 cases were G1 and 3 cases were G2 in conventional ESD group without significant difference (P=0.680). There were no significant differences in baseline data between in the two groups (all P>0.05). All the basal resection margins were negative, the en bloc resection rate was 100% and the R0 resection rate was 100%. Pathological results showed tumor tissue close to the burning margin in 5 cases of conventional ESD group and in 2 cases of DFS-ESD group (P=0.416). The operation time was (17.9±6.6) minutes in conventional ESD group and (14.7±3.3) minutes in DFS-ESD group (t=1.776, P=0.084). The modified operation time of DFS-ESD group was (11.9±2.8) minutes, which was significantly shorter than (17.9±6.6) minutes in conventional ESD group (t=3.425, P=0.002). The hospital stay was (2.3±0.6) days and (2.0±0.5) days in conventional ESD group and DFS-ESD group, respectively, without significant difference (t=1.436, P=0.160). No patient was transferred to surgery, and no delayed bleeding or perforation occurred in either group. There was no recurrence or primary tumor-related death, and all the patients recovered well during a follow-up period of 14(1-24) months. Conclusion: Dental floss traction-assisted ESD for rectal neuroendocrine neoplasm can simplify operation and ensure negative basal margin.

[Efficacy of RCDOP regimen in the treatment of patients with diffuse large B-cell lymphoma]

Objective: To investigate the efficacy of RCDOP (Rituximab, cyclophosphamide, liposome doxorubicin, vincristine and prednisone) regimen in patients with de novo diffuse large B-cell lymphoma (DLBCL), especially in those patients with multiple extra-nodal involvement or Bulky diseases. Methods: A total of 87 newly diagnosed DLBCL patients who received RCDOP regimen from October 2012 to October 2017 were enrolled into this study. Survival functions were estimated using the Kaplan-Meier method and compared by the log-rank test, and χ(2) tests were used for categorical data. Results: Among the 87 DLBCL patients treated with RCDOP regimen, 81 patients achieved complete remission (CR) or partial remission (PR), with ORR as 93.1%. Patients were further classified into groups, according to the risk factors, such as IPI scores, multiple extra-nodal involvement, bulky disease, age>60, tumor Ki-67>80%, elevated serum LDH level and advanced Ann Arbor stage. The progression-free survival (PFS, P=0.084) and overall survival (OS, P=0.515) had no statistical difference among the IPI low risk (0-1 score) group, intermediate risk (2-3 scores) group and high risk (4-5 scores) group. Similarly, no statistical difference were fou nd in PFS and OS of patients with extra-nodal involvements ≥2 (P=0.303 and P=0.624), with bulky disease (P=0.518 and P=0.466), with age>60 (P=0.600 and P=0.183), with elevated serum LDH level (P=0.054 and P=0.880), with advanced Ann Arbor stage (P=0.075 and P=0.286), and with tumor Ki-67 over 80% (P=0.190 and P=0.109), when compared with those of patients without these risk factors. Conclusion: RCDOP can improve the therapeutic effect and prognosis of DLBCL patients with certain high risk factors, such as intermediate and high IPI risks, multiple extra-nodal involvements, bulky disease, age over 60, elevated LDH level, advanced Ann Arbor stage and tumor Ki-67 over 80%.

[Killing activity of nonequilibrium plasma against young and old Enterococcus faecalis biofilms with long-term exposure in infected root canals in vitro]

Objective: To evaluate the antimicrobial activity of nonequilibrium plasma against Enterococcus faecalis (Ef) biofilms in vitro and to obtain novel evidence of root canal disinfection with nonequilibrium plasma. Methods: Sterile cover slips and single-rooted canals were filled with Ef and incubated to form 1-week-old and 3-week-old biofilms, respectively. The infected samples were subjected to nonequilibrium plasma, 2% chlorhexidine digluconate (CHX) and saline for 3, 10 and 30 minutes, respectively. After treatment, the killing effectiveness of nonequilibrium plasma was analyzed by using laser scanning confocal microscopy (LSCM) and colony forming unit (CFU) counting. Results: The 3-dimentional reconstruction LSCM images showed that about 48.3%-79.8% of 1-week-old Ef biofilm cells and 40.0%-67.4% of 3-week-old biofilm cells were killed by nonequilibrium plasma and 2% CHX compared to saline (P<0.05). The proportion of killing activity was lower after 3 minutes (40.0%-50.9% killing) than after 10 minutes (65.3%-77.8% killing) and 30 minutes (66.4%-79.8% killing) (P<0.05). And the killing of biofilm bacteria was fastest during the first 3 minutes (13.3%-17.0% killing per minute) and slow down greatly after 10 minutes. Remarkably more bacteria were killed in 1-week-old Ef biofilms (48.3%-79.8% killing) than in 3-week-old biofilms (P<0.05). Conclusions: The nonequilibrium plasma killed more Ef biofilm cells in infected root canals showed promotional as an additional approach against bacterial biofilms during root canal disinfection.

Longitudinal evaluation of markers of inflammation in HIV-positive and HIV-negative Rwandan women

OBJECTIVES

African women are disproportionately affected by HIV infection and may experience non-AIDS-related complications associated with inflammation. High-sensitivity C-reactive protein (hsCRP), d-dimer and transthyretin have been examined as inflammatory markers elsewhere, but it is unclear how they change over time in HIV-negative or HIV-positive African women with or without antiretroviral therapy (ART) initiation.

METHODS

We examined hsCRP, d-dimer and transthyretin levels at baseline and at follow-up of ≥2 years in 185 HIV-negative and 510 HIV-positive Rwandan women who were ART naïve at study entry. Generalized estimating equations for each marker were used to investigate the association with HIV infection/CD4 count, ART and follow-up time.

RESULTS

Compared with HIV-negative women, HIV-positive women had higher hsCRP and d-dimer and lower transthyretin concentrations, with greater differences at lower CD4 counts. After adjusting for CD4 count and other factors, ART was not significantly associated with log hsCRP (P = 0.36) at follow-up, but was independently associated with lower log d-dimer (P = 0.03) and higher transthyretin (P = 0.0008) concentrations. At ≥ 2 years of follow-up, hsCRP had not significantly changed in any group but log d-dimer had decreased significantly in all groups. Transthyretin declined significantly over time in HIV-negative women and HIV-positive non-ART initiators, but increased significantly in HIV-positive ART initiators.

CONCLUSIONS

HIV infection and advanced immune suppression were associated with higher hsCRP and d-dimer and lower transthyretin concentrations. ART (independently of CD4 changes) was significantly associated with decreases in d-dimer and increases in transthyretin, but, in contrast to other studies, was not associated with decreases in hsCRP. We found no change in hsCRP over time in any group.

Labour patterns in Chinese women in Chongqing

OBJECTIVE

To obtain data on the characteristics of labour from a regional sample of Chinese parturients and to assess the pattern of progress of labour among nulliparous women.

DESIGN

A prospective observational study.

SETTING

The study was conducted in the First Affiliated Hospital of Chongqing Medical University.

POPULATION

The final sample involved 1200 Chinese parturients with singleton, vertex and term gestation; spontaneous onset of labour; vaginal delivery; and without adverse perinatal outcomes.

METHODS

A repeated-measures analysis was used to depict labour curves while an interval-censored regression was used to estimate the duration of labour centimetre by centimetre.

MAIN OUTCOME MEASURES

Labour curves and the duration of labour at the 50th and 95th percentiles.

RESULTS

Among 1091 nulliparous women, 57.7% had cervical dilation of 3 cm or less at the time of admission, and the mean duration of the first stage of labour was 9.1 ± 3.3 hours. From 5 to 9 cm of cervical dilation it sometimes took more than 2 hours for dilation to advance 1 cm. No obvious inflection points appeared in the labour curve of Chinese nulliparae, and no deceleration was observed.

CONCLUSION

Progress of labour in Chinese parturients was more gradual than in their Western counterparts. Obstetric practice standards based on data generated from Western countries may not be appropriate for Chinese women.

TWEETABLE ABSTRACT

A prospective study has evaluated labour patterns in Chinese women using regional data from nulliparae.

Abstract P3-07-08: Temozolomide as a targeted therapy strategy for triple negative breast cancer

BACKGROUND:

Approximately 15% of newly diagnosed breast cancers are classified as triple negative (TNBC). TNBCs are considered more aggressive and have a worse prognosis as no targeted therapies are currently available. These tumors are routinely treated with chemotherapy agents with only modest proven efficacy.

Temozolomide (TMZ) is an oral chemotherapy agent commonly used for the treatment of brain tumors and melanoma. TMZ is an alkylating agent, and its therapeutic benefit depends on its ability to alkylate/methylate DNA, most commonly at the N-7 or O-6 positions of guanine residues. This process leads to DNA damage and subsequently triggers cell death. Cells that express the enzyme O6-Methylguanine-DNA Methyltransferase (MGMT) are able to repair damage caused by TMZ. Tumors that lack expression of MGMT, owing to methylation of the gene promoter, demonstrate a better response to TMZ treatment as a result of synthetic lethality.

It was first reported in 2012 that TNBCs were more likely to be MGMT methylated, which was confirmed by another group that reported up to 64% of wild-type BRCA1 TNBC exhibited MGMT gene methylation. In 2013 it was found that basal-like breast cancers were more likely to be MGMT methylated and linked to larger tumor size. Together these findings suggest that a sub-population of TNBCs lack MGMT expression, due to promoter methylation.

Currently, TMZ is not a treatment option for breast cancers given the modest efficacy of TMZ noted in breast cancer clinical trials; however, most of these trials have focused on using this agent to either treat or prevent brain metastases, due to TMZs ability to cross the blood-brain barrier. Importantly, none of these trials investigated MGMT expression or specifically TNBC populations.

We hypothesize that TMZ may be a viable and efficacious treatment option for TNBCs that lack MGMT expression, due to promoter methylation.

METHODS:

We analyzed 12 archival specimens and 4 TNBC cell lines (HTB132, HTB26, HTB126 and HCC1806) for MGMT expression using a qRT-PCR clinical assay available from Calgary Laboratory Services. Additionally, we also looked at MGMT protein expression in the cell lines using Western Blot analysis to confirm the qRT-PCR results. Finally, we performed an in vitro assay with TNBC cell lines to determine cytotoxicity of TMZ.

RESULTS:

Analysis of the archival specimens found that 33% of samples analyzed had MGMT promoter methylation by qRT-PCR. Additionally, we found that HTB26 and HTB126 cell lines showed MGMT promoter methylation by qRT-pCR analysis. Western Blot analysis confirmed lack of MGMT expression in these two cell lines, and also identified another cell line (HCC1806) lacking MGMT protein that was classified as unmethylated by the qRT-PCR clinical assay. Moreover, our in vitro assay found that two cell lines (HTB26 and HCC1806) showed a noticeable response to treatment with TMZ. Interestingly, HTB126 did not show response to TMZ, suggesting that there may be another putative resistance pathway.

CONCLUSIONS:

Preliminary findings suggest that TMZ may be a viable targeted treatment option for TNBCs. Currently, we are investigating drug response using in vivo mouse models, as well as investigating synergistic combination therapy options.

Citation Format: Kornaga EN, Gratton K, Shi Q, Yang A, Nixon NA, Roldan Urgoiti G, Morris DG. Temozolomide as a targeted therapy strategy for triple negative breast cancer [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 P3-07-08.

Prognostic value of primary tumour resection in synchronous metastatic colorectal cancer: Individual patient data analysis of first-line randomised trials from the ARCAD database

Indication for primary tumour resection (PTR) in asymptomatic metastatic colorectal cancer (mCRC) patients is unclear. Previous retrospective analyses suggest a survival benefit for patients who underwent PTR. The aim was to evaluate the prognostic value of PTR in patients with synchronous mCRC by analysis of recent large RCTs including systemic therapy with modern targeted agents. Individual patient data (IPD) of 3423 patients enrolled into 8 randomised controlled trials (RCTs) with first-line systemic therapy in the ARCAD (Aide et Recherche en Cancérologie Digestive) database were analysed. The number of patients with unresected synchronous mCRC, resected synchronous mCRC and metachronous mCRC was 710 (21%), 1705 (50%) and 1008 (29%), respectively. Adjusting for age, gender, performance status (PS) and prior chemotherapy, the unresected group had a significantly worse median overall survival (16.4 m) compared with the synchronous resected (22.2 m; hazard ratio [HR] 1.60, 95% CI 1.43-1.78) and metachronous (22.4 m; HR 1.81, 95% CI 1.58-2.07) groups. Similarly, median progression-free survival was significantly worse for the unresected group compared with the synchronous resected (HR 1.31, 95% CI 1.19-1.44) and metachronous (HR 1.47, 95% CI 1.30-1.66) groups. In a multivariate analysis, the observed associations remained significant. This largest IPD analysis of mCRC trials to date demonstrates an improved survival in synchronous mCRC patients after PTR. These results may be subject to bias since reasons for (non)resection were not available. Until results of ongoing RCTs are available, both upfront PTR followed by systemic treatment and upfront systemic treatment are considered appropriate treatment strategies.