Overexpression of cry1c* Enhances Resistance against to Soybean Pod Borer (Leguminivora glycinivorella) in Soybean

Soybean [Glycine max (L.) Merr.], an essential staple food and oil crop worldwide, boasts abundant vegetable proteins and fats beneficial for both human and animal consumption. However, the soybean pod borer (Leguminivora glycinivorella) (SPB) stands as the most destructive soybean insect pest in northeast China and other northeastern Asian regions, leading to significant annual losses in soybean yield and economic burden. Therefore, this study aims to investigate the introduction of a previously tested codon-optimized cry1c gene, cry1c*, into the soybean genome and assess its effect on the SPB infestation by generating and characterizing stable transgenic soybeans overexpressing cry1c*. The transgenic soybean lines that constitutively overexpressed cry1c* exhibited a significant reduction in the percentage of damaged seeds, reaching as low as 5% in plants under field conditions. Additionally, feeding transgenic leaves to the larvae of S. exigua, S. litura, and M. separta resulted in inhibited larval growth, decreased larval body weight, and lower survival rates compared to larvae fed on wild-type leaves. These findings showed that the transgenic lines maintained their resistance to SPB and other lepidopteran pests, especially the transgenic line KC1. Southern blotting and genome-wide resequencing analysis revealed that T-DNA integration occurred as a single copy between loci 50,868,122 and 50,868,123 of chromosome 10 in the transgenic line KC1. Therefore, the transgenic line KC1, overexpressing high levels of cry1c* in leaves and seeds, holds strong potential for commercial use in the integrated management of SPB and other lepidopteran pests.

Long-term Effectiveness of Integrated Caries Preventive Programs in Thailand Among Preschool Children Using a System Dynamics Model

OBJECTIVE

To compare the effect of three caries preventive interventions provided by Thailand's Ministry of Public Health (MOPH): supervised toothbrushing (STB), fluoride varnish (FV), and combined STB+FV from 0 to 5 years old to the base case using the System Dynamics Model (SDM).

METHODS

The SDM was developed to compare the intervention scenarios: STB, FV, and combined STB+FV with the base case scenario. Meta-analyses determined the effective rates of the interventions included in the model.

RESULTS

The model indicated that the population with no caries in deciduous teeth increased by 7.5%, 5.7%, and 4.2% at three years of age, and 12.8%, 9.9%, and 5.9% at five years of age, under STB+FV, STB, and FV respectively when compared to the base case. At three years old, the population with untreated caries in deciduous teeth decreased by 12.9% in STB+FV, 9.8% in STB, and 7.3% in FV, and by 10.9% in STB+FV, 8.5% in STB, and 4.9% in FV, at five years old. The increase in the population without caries is considered clinically significant compared to baseline.

CONCLUSION

The model determined that an effective combination of STB and FV should be administered between 0 and 5 years of age to reduce caries in the primary dentition. The SDM could be applied as a "what-if" analysis in order to determine the most beneficial intervention or policy by comparing them.

Abstract P1-16-04: Risk of venous thromboembolism with abemaciclib based regimen versus other CDK 4/6 inhibitor containing regimens in patients with hormone receptor-positive HER2-negative metastatic breast cancer

Background: Approximately 70% of patients with metastatic breast cancer (MBC) are hormone receptor (HR) - positive and the cyclin dependent kinases (CDK) along with their D-type cyclin catalysts, have been shown to play a role in mediating the resistance to endocrine therapy. Several CDK-targeted agents have been recently approved by FDA. Nevertheless, the risk of venous thromboembolism (VTE) with the use of different CDK 4/6 inhibitors has never been reported. We undertook a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of VTE with abemaciclib based regimens versus other CDK 4/6 inhibitor containing regimens in patients with HR-positive HER2-negative MBC.

Methods: We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through February 2018. The randomized controlled trials that mention deep vein thrombosis and pulmonary embolism as adverse effects of CDK 4/6 inhibitor therapy were incorporated in the analysis. The primary meta- analytic approach was a fixed effects model using the Mantel-Haenszel (MH) method. It was used to calculate the estimated pooled risk ratio (RR) and risk difference (RD) with 95% confidence interval (CI).

Results: Five phase 3 studies and one phase 2 study with a total of 3,159 patients with HR-positive HER2-negative MBC were eligible for analysis. The study arms used palbociclib-letrozole, palbociclib-fulvestrant, ribociclib-letrozole, abemaciclib-fulvestrant, and abemaciclib-nonsteroidal aromatase inhibitors (either letrozole or anastrozole) while the control arms utilized placebo in combination with letrozole or anastrozole or fulvestrant. The randomization ratio was 2 to 1 in PALOMA-2, PALOMA-3, MONARCH-2 and MONARCH-3 studies and 1 to 1 in PALOMA-1 and MONALEESA-2 trials. CDK 4/6 inhibitors were utilized as first line treatment in PALOMA-1, PALOMA-2, MONALEESA-2 and MONARCH-3. The I2 statistic for heterogeneity was 0, and the heterogeneity X2 (Cochran's Q) was 1 (P= 0.707), suggesting homogeneity among RCTs. The VTE incidence was 25 (3.255%) in the abemaciclib group vs 2 (0.520%) in the control group. The pooled relative risk for VTE was 6.222 (95% CI: 1.481 – 26.145, P = 0.013) and the absolute RD was 0.027 (95% CI: 0.013 – 0.042, P < 0.0001). In other CDK 4/6 inhibitor containing regimens, the VTE incidence was reported at 15 (1.243%) vs 2 (0.374%) in the control arm. The pooled RR for VTE was 2.312 (95% CI: 0.852 –6.272, P = 0.100) and the absolute RD was 0.008 (95% CI: - 0.000 – 0.017, P = 0.259).

Conclusion: VTE is a major cause of morbidity and mortality and is particularly common in patients with breast cancer. Our meta-analysis demonstrated that the addition of abemaciclib to endocrine therapy notably contributed to a higher incidence of VTE with a relative risk of 6.22. However, no significant increase in the risk of VTE was noted in other CDK 4/6 inhibitor-based regimen. More randomized trials are required to determine the actual relation and definitive incidence of VTE among different CDK-targeted agents when added to endocrine therapy.

Citation Format: Thein KZ, Ball S, Zaw MH, Quirch M, Hardwicke F, Awasthi S, Oo TH, Jones C. Risk of venous thromboembolism with abemaciclib based regimen versus other CDK 4/6 inhibitor containing regimens in patients with hormone receptor-positive HER2-negative metastatic 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 P1-16-04.

Abstract P3-14-02: Incidence of venous thromboembolism in patients with hormone receptor-positive HER2-negative metastatic breast cancer treated with CDK 4/6 inhibitors: A systematic review and meta- analysis of randomized controlled trials

Background:

The cyclin dependent kinases (CDK) along with their partners, the cyclins, have a crucial role in regulation of the cell cycle. Several CDK-targeted agents have been employed in hormone receptor positive metastatic breast cancer (MBC) with noteworthy safety concerns. Nevertheless, the impact of this agent on risk of venous thromboembolism (VTE) remains uncertain. We performed a systematic review and meta-analysis of randomized controlled trials (RCT) to determine the risk of VTE among patients with hormone receptor-positive HER2-negative MBC treated with CDK 4/6 inhibitors.

Methods:

We systematically conducted a comprehensive literature search using MEDLINE, EMBASE databases and meeting abstracts through June 2017. Trials that mention deep vein thrombosis and pulmonary embolism as adverse effects were incorporated in the analysis. The primary meta- analytic approach was a fixed effects model using the Mantel-Haenszel (MH) method. It was used to calculate the estimated pooled risk ratio (RR), and risk difference (RD) with 95% confidence interval (CI). Pooled VTE rates were estimated as follows: we multiplied the median follow-up duration by the sample size. Crude study-specific VTE rates were then calculated by dividing the number of incident VTE cases by the total number of person-months follow-up.

Results:

A total of 2671 patients with hormone receptor-positive HER2-negative MBC from four phase 3 studies and one phase 2 study were eligible for analysis. The study arm used palbociclib-letrozole, palbociclib-fulvestrant, ribociclib-letrozole and abemaciclib-fulvestrant while the control arm utilized placebo in combination with letrozole or fulvestrant. The I2 statistic for heterogeneity was 13.6, and the heterogeneity X2 (Cochran's Q) was 4.6 (P= 0.3), suggesting homogeneity of results among the randomized trials. The VTE incidence was 24 (1.46%) in CDK 4/6 group vs 4 (0.39%) in control group. The pooled RR for VTE was 2.736 (95% CI: 1.115 – 6.714, P = 0.028) and the absolute RD was 0.010 (95% CI: 0.002 – 0.018, P = 0.010) according to the fixed effects model. By the random effects model, the pooled RR was 2.411 (95% CI: 0.809 – 7.181, P = 0.114) and RD was 0.009 (95% CI: 0.0 – 0.019, P = 0.048). Over median follow up of 36 months, the RR for VTE was 3.792 (95% CI: 1.838 – 7.822, P < 0.0001) and RD was 0.024 (95% CI: 0.014 – 0.034, P < 0.0001) with the fixed effects model. By the random effects model, the pooled RR for VTE was 4.248 (95% CI: 0.952- 18.959, P = 0.058) and RD was 0.026 (95% CI: 0.004 – 0.021, P < 0.0001). The pooled rate of VTE among CDK 4/6 group was 2.99 per person years compared to 0.50 per person years among control arm.

Conclusion:

Approximately 1% of patients on letrozole or fulvestrant alone developed VTE in previous studies. Our meta-analysis demonstrated that the addition of CDK 4/6 inhibitors to letrozole or fulvestrant, contribute to higher incidence of VTE. More randomized trials are required to determine the actual relation and definitive incidence of VTE, a major cause of morbidity and mortality among these patients.

Citation Format: Thein KZ, Zaw MH, Tun AM, Jones C, Radhi S, Hardwicke F, Oo TH. Incidence of venous thromboembolism in patients with hormone receptor-positive HER2-negative metastatic breast cancer treated with CDK 4/6 inhibitors: A systematic review and meta- analysis of randomized controlled trials [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 P3-14-02.