Construction of test strips for lung cancer detection based on aptamers.

Lung cancer is the most common malignancy worldwide. Early diagnosis helps to reduce mortality and improve survival. Aptamers are widely used in cancer screening because of their high specificity, good stability and low cost. In this study, using the specific aptamer of lung cancer serum, the sandwich method colloidal gold test strip was prepared by isothermal amplification technique and the principle of nucleic acid hybridisation for the early diagnosis of lung cancer. The results showed that the test strip was positive in 8 patients with lung cancer, which was consistent with the actual cases. The test strip can accurately identify lung cancer patients. The concentration range of nucleic acid detection is 1 × 10-4 - 7 × 10-4 mol/L, and the detection limit is 0.67 mM. The test strip detection method has low cost and simple operation, and provides a reference for the development of home portable tumor early detection.

Screening and application of inhibitory aptamers for DNA repair protein apurinic/apyrimidinic endonuclease 1.

The base excision repair (BER) pathway is crucial for DNA repair, and apurinic/apyrimidinic endonuclease 1 (APE1) is a critical enzyme in this pathway. Overexpression of APE1 has been linked to multidrug resistance in various cancers, including lung cancer, colorectal cancer, and other malignant tumors. Therefore, reducing APE1 activity is desirable to improve cancer treatment. Inhibitory aptamers, which are versatile oligonucleotides for protein recognition and function restriction, are a promising tool for this purpose. In this study, we developed an inhibitory aptamer for APE1 using systematic evolution of ligands by exponential (SELEX) technology. We used carboxyl magnetic beads as the carrier and APE1 with a His-Tag as the positive screening target, while the His-Tag itself served as the negative screening target. The aptamer APT-D1 was selected based on its high binding affinity for APE1, with a dissociation constant (Kd) of 1.306 ± 0.1418 nM. Gel electrophoresis analysis showed that APT-D1 at a concentration of 1.6 µM could entirely inhibit APE1 with 21 nM. Our results suggest that these aptamers can be utilized for early cancer diagnosis and the treatment, and as an essential tool for studying the function of APE1.

Optimal waiting period for frozen embryo transfer after hysteroscopic polypectomy: A propensity score matching analysis.

Objective: To evaluate the optimal waiting period for frozen-thawed embryo transfer (FET) after hysteroscopic polypectomy (HSC-P). Design: Retrospective cohort. Setting: University-affiliated hospital. Patients: All patients included in this research underwent hysteroscopy before the first FET cycle after whole embryo freezing. A total of 206 patients had undergone HSC-P, and 3681 patients without endometrial polyps were defined as the controls. Interventions: HSC-P. Main outcome measures: The HSC-P group was divided into three subgroups based on the time interval between HSC-P and the start of an FET cycle. Subgroup 1 consisted of patients who underwent FET after their next menses, subgroup 2 after two menstrual cycles, and subgroup 3 after three or more menstrual cycles. Demographics, baseline in vitro fertilization (IVF) characteristics, and pregnancy outcomes, especially perinatal outcomes after FET were compared among the groups. Results: There were 137 patients in subgroup 1, 40 in subgroup 2, and 29 in subgroup 3. There were no differences in the baseline characteristics of the three groups. IVF-related data and FET-related data, such as endometrial thickness and ET no. Of embryoes, were similar among the three subgroups. The three subgroups showed no significant differences in implantation rate, biochemical pregnancy rate, abortion rate, clinical pregnancy rate or live birth rate. Besides, There was no significant difference in perinatal outcomes including very preterm delivery, preterm delivery, low birth weight, macrosomia, small for gestational age, large for gestational age, birth weight(g), birth-height(cm)and Apgar Scores. Conclusions: Compared with FET after their next menses, FET after two or more menstrual cycles after HSC-P does not necessarily produce superior outcomes.

Hypoxia induction of SH2D3A triggers malignant progression of lung cancer.

Lung cancer is the most prevalent and aggressive cancer and is one of the leading causes of cancer-related death worldwide. Hypoxia in the tumor microenvironment is associated with poor patient survival and is a crucial characteristic of solid tumors. A subset of tumor cells, termed cancer stem cells (CSCs), with self-renewal and differentiation capabilities simultaneously, are regarded as responsible for cancer tumorigenesis, resistance to therapeutics, and cancer relapse. Recent advances have revealed that hypoxia plays an essential role in CSCs self-replication maintenance. Yet, the underlying mechanisms of hypoxia that trigger the stemness maintenance of CSCs are still poorly understood. Here, we provide evidence showing that SH2D3A expression level was increased in lung cancer and lung CSCs, and high expression of SH2D3A was associated with the overall survival of patients with lung cancer. Mechanistically, HIF-2α, which is a key transcription factor in response to hypoxia directly binds to the SH2D3A promoter and facilitates SH2D3A expression at the transcription level. SH2D3A was found to be functionally important for lung CSC malignant behaviors such as uncontrolled self-replication and proliferation. We demonstrated that pharmacological downregulation of SH2D3A expression by AM966, a small molecule compound, efficiently induces tumor regression in vitro and in vivo. Thus, this study highlights the biological implications of SH2D3A as a novel prognostic marker and therapeutic target in lung cancer in the future.

Prediction and prognostic significance of ALOX12B and PACSIN1 expression in gastric cancer by genome-wide RNA expression and methylation analysis.

BACKGROUND: Stomach adenocarcinoma (STAD) is one of the common gastrointestinal cancers, characterized by late discovery and metastasis. However, research of gene methylation and expression in gastric cancer (GC) metastasis has been quite limited. This study aimed to investigate the altered gene expression patterns between metastasis and non-metastasis samples using high-throughput RNA and methylation profiles from a large number of patients. Another aim was to identify a specific potential metastasis biomarker, with the ability to predict the metastasis possibility and prognosis of patients with STAD. METHODS: In this study, we integrated The Cancer Genome Atlas (TCGA) program STAD datasets, analyzed the RNA expression and DNA methylation data between non-metastasis (M0) and distant metastasis (M1) samples, and evaluated the candidate biomarker in survival and prognosis of GC. RESULTS: Among all patients enrolled, 329 with M0 and M1 information were positive for RNA analysis, and 353 with M0 and M1 information were positive for methylation analysis. We found 29 upregulated and 200 downregulated genes in RNA level, and 5,046 hypermethylated and 8,563 hypomethylated probes in methylation level. Among these genes, we found high RNA expression level and low DNA methylation level of ALOX12B and PACSIN1 in GC metastasis samples. Patients with high expression of these 2 genes had poor overall survival (OS), progression-free survival (PFS), and post-progression survival (PPS). CONCLUSIONS: The expression levels of ALOX12B and PACSIN1 were higher in the metastasis than non-metastasis group, and participants with high expression of these 2 genes were found to have poor survival. The genes ALOX12B and PACSIN1 are potential biomarkers of metastasis and poor prognosis, especially in early stage GC, and provide additional information for subsequent comprehensive treatment of GC.