A Feasibility Study of Capecitabine and Oxaliplatin for Patients with Stage II/III Colon Cancer -ACTOR Study

Retrospective cohort study for thrombocytopenia during concurrent chemoradiotherapy for rectal cancer

Background

The aim of this article was to establish the clinical prognostic models and identify the predictive radiation dosimetric parameters for thrombocytopenia during concurrent chemoradiotherapy for rectal cancer.

Methods

In this retrospective cohort study, patients with rectal adenocarcinoma undergoing concurrent long-term chemoradiotherapy were included. The primary outcome of interest was grade 2 or higher (2+) thrombocytopenia (platelet(PLT) count <75,000/μL). Secondary outcomes included: grade 1 or higher thrombocytopenia (PLT count<100,000/μL) and the PLT count during chemoradiotherapy and its nadir. The risk prediction model was developed by logistic regression to identify clinical predictors of 2+ thrombocytopenia. Univariate linear regression models were used to test correlations between radiation dosimetric parameters and the absolute PLT count at nadirs.

Results

This retrospective cohort comprised 238 patients. Fifty-four (22.6%) patients developed thrombocytopenia during concurrent chemoradiotherapy, while 15 (6.3%) patients developed 2+ thrombocytopenia. Four independently associated risk factors, including age, Alb level, PLT count, and chemotherapy regimen, were included in the final model and used to form a 2+ thrombocytopenia probability estimation nomogram. The C-index was 0.87 (95% CI: 0.78-0.96). The calibration plot showed a moderate agreement, and the Brier score was 0.047 (95% CI: 0.025-0.070). The total absolute volume of bone marrow irradiated by 5 Gy, 10 Gy and 15 Gy of radiation (BM-V5ab, BM-V10ab, BM-V15ab), calculated by the volume of bone marrow multiplied by the corresponding Vx, were identified as new predictors. The nadir of PLT was found to be negatively correlated with BM-V5ab (β = -0.062, P =0.030), BM-V10ab (β = -0.065, P =0.030) and BM-V15ab (β = -0.064, P =0.042).

Conclusion

The occurrence of 2+ thrombocytopenia during concurrent chemoradiotherapy for rectal cancer can be predicted by the patient's baseline status and chemoradiotherapy regimen, and low dose irradiation of bone marrow can affect the level of platelets during the treatment.

MicroRNA-363-3p, negatively regulated by long non-coding RNA small nucleolar RNA host gene 5, inhibits tumor progression by targeting Aurora kinase A in colorectal cancer

MicroRNA-363-3p (miR-363-3p), reportedly, exhibits a tumor-suppressive role in human malignancies. Herein, our research was designed to further explain the functions and molecular mechanisms of miR-363-3p in the progression of colorectal cancer (CRC). With in vitro models, this study found that miR-363-3p was markedly under-expressed in CRC tissues and cells, and its overexpression suppressed the viability, migration, and invasion of CRC cells, and promoted cell apoptosis, whereas inhibiting miR-363-3p expression exhibited an opposite role. Additionally, aurora kinase A (AURKA), capable of counteracting the impacts of miR-363-3p on malignant biological behaviors of CRC cells, was identified as a direct target of miR-363-3p. Besides, miR-363-3p was sponged by long non-coding RNA small nucleolar RNA host gene 5 (SNHG5), which suppressed miR-363-3p expression. This research shows that SNHG5/miR-363-3p/AURKA axis partakes in CRC progression.

The Long Non-Coding RNA-RoR Promotes the Tumorigenesis of Human Colorectal Cancer by Targeting miR-6833-3p Through SMC4

BACKGROUND

Long non-coding RNA regulator of reprogramming (LINC-RoR) has shown different expressions in a variety of tumors as a stem cell inducer through reprogramming regulation. However, its role and regulation mechanisms in colorectal cancer (CRC) are still unclear.

MATERIALS AND METHODS

Quantitative real-time PCR and Western blot were performed to examine LINC-RoR expression in paired CRC samples and cell lines. The relationship of LINC-RoR expression with clinicopathological characteristics and clinical outcomes was analyzed. The biological functions of LINC-RoR were studied by MTS and colony formation in vitro. Cell apoptosis was analysed by the flow cytometry. The Dual-luciferase reporter assays and RIP assays were performed to explore the regulatory relationship of LINC-RoR.

RESULTS

In this study, we found that LINC-RoR was upregulated in CRC cell lines and tissues. High expression of LINC-RoR was associated with poorer survival time and multivariate analysis results showed that LINC-RoR was an independent risk factor of tumor malignancy progression. Overexpression of LINC-RoR promoted the cell proliferation and knocked down it can reverse the effect in vitro. The regulatory network of LINC-ROR/miR-6833-3p/SMC4 was predicted with bioinformatics analysis tools and validated via dual-luciferase reporter assays and RIP. Further study revealed that in overexpression LINC-RoR cell lines the expression of miR-6833-3p was downregulated and miR-6833-3p can inhibit its target gene SMC4, the apoptosis-related protein.

CONCLUSION

We concluded that LINC-RoR functions as an oncogene in CRC through the miR-6833-3p/SMC4 pathway.

LINC00957 Acted as Prognostic Marker Was Associated With Fluorouracil Resistance in Human Colorectal Cancer

Colorectal cancer (CRC) is one of the most prevalent digestive tumors in China. Recent studies indicate that long intergenic non-coding RNAs (lincRNAs) play a crucial role in predicting survival for CRC patients. However, the novel lincRNA, LINC00957, is largely unclear in CRC. The purpose of the current study was to determine LINC00957 expression, assess its the clinical significance and explore the potential mechanism in CRC. The qRT-PCR was used to quantify the expression levels of LINC00957 in tissues and cell lines. Our research revealed that LINC00957 was significantly higher expression in CRC. In addition, the LINC00957 expression was associated with TNM stage and chemotherapy outcome, but age, gender, tumor size, histological grade, primary tumor location. CRC patients with high LINC00957 expression level showed poor overall survival (P = 0.002). Multivariate survival analysis indicated that LINC00957 was a prognostic factor for CRC patients (P = 0.010). Mechanically, inhibition of LINC00957 expression reversed 5-FU resistance by down-regulating P-gP. In summary, our study indicated that this novel lncRNA expression signature might be a useful biomarker of the prognosis and therapeutic target for CRC patients.