LncRNA UCA1 regulates proliferation, migration and invasion of cervical cancer cells by targeting miR-145

OBJECTIVE

Finding a key target for the development of cervical cancer is conducive to the treatment of cervical cancer. LncRNA UCA1 plays a role in multiple tumors, such as the digestive tract and bladder. However, whether LncRNA UCA1 plays a role in cervical cancer is unclear.

PATIENTS AND METHODS

The tumor tissues (tumor group) and adjacent tissues (normal group) of cervical cancer patients were collected for analysis of expression of LncRNA UCA1 and miR-145 by Real Time-Polymerase Chain Reaction (RT-PCR). Cervical cancer HeLa cell line was cultured and divided into NC group, si-UCA1 group, and si-UCA1+ miR-145 inhibitor group. It was followed by the analysis of LucRNA UCA1 expression by Real Time-PCR, cell proliferation by MTT assay, cell migration and invasion by respective cell scratch, transwell chamber assay, and targeted relationship between UCA1 and miR-145 by Dual-Luciferase activity.

RESULTS

LncRNA UCA1 expression was significantly increased in cervical cancer and miR-145 expression was decreased compared with the normal group (p<0.05). There was a negative correlation between them (p<0.05). The downregulation of UCA1 significantly inhibited tumor cell proliferation, migration, and invasion compared with NC group (p<0.05). MiR-145 is the target miRNA of UCA1. The addition of miR-145 inhibitor reversed the effect of UCA1 siRNA on downregulating UCA1 expression, and the difference was statistically significant compared with the si-UCA1 group (p<0.05).

CONCLUSIONS

LncRNA UCA1 expression is significantly increased in cervical cancer and miR-145 expression is decreased with a negative correlation between them. Lnc-RNA UCA1 regulates cervical cancer cell proliferation, migration, and invasion by targeting miR-145.

Unconventional Transverse Transport above and below the Magnetic Transition Temperature in Weyl Semimetal EuCd_{2}As_{2}

As exemplified by the growing interest in the quantum anomalous Hall effect, the research on topology as an organizing principle of quantum matter is greatly enriched from the interplay with magnetism. In this vein, we present a combined electrical and thermoelectrical transport study on the magnetic Weyl semimetal EuCd_{2}As_{2}. Unconventional contribution to the anomalous Hall and anomalous Nernst effects were observed both above and below the magnetic transition temperature of EuCd_{2}As_{2}, indicating the existence of significant Berry curvature. EuCd_{2}As_{2} represents a rare case in which this unconventional transverse transport emerges both above and below the magnetic transition temperature in the same material. The transport properties evolve with temperature and field in the antiferromagnetic phase in a different manner than in the paramagnetic phase, suggesting different mechanisms to their origin. Our results indicate EuCd_{2}As_{2} is a fertile playground for investigating the interplay between magnetism and topology, and potentially a plethora of topologically nontrivial phases rooted in this interplay.

MiR-101 affects proliferation and apoptosis of cervical cancer cells by inhibition of JAK2

OBJECTIVE

JAK2 expression and dysfunction play a role in tumor pathogenesis. Bioinformatics analysis revealed a targeted binding site between miR-101 and the 3'-UTR of JAK2 mRNA. This study investigated the role of miR-101 in regulating JAK2 expression and affecting the proliferation and apoptosis of cervical cancer cells.

PATIENTS AND METHODS

The tumor tissues and adjacent tissues of patients with cervical cancer were collected. The expression of miR-101 and JAK2 was detected by qRT-PCR. The dual luciferase reporter gene assay validated the targeting relationship between miR-101 and JAK2. The cervical cancer Caski cells were cultured in vitro, and divided into miR-NC group and miR-101 mimic group. The expression of JAK2 and p-JAK2 was detected by Western blot, cell apoptosis was detected by flow cytometry, and cell proliferation was detected by EdU staining.

RESULTS

Compared with adjacent tissues, miR-101 expression was significantly decreased, and JAK2 expression was increased in cervical cancer tissues. There was a targeted regulatory relationship between miR-101 and JAK2. Compared with HcerEpic cells, miR-101 expression in HeLa and Caski was significantly decreased, and the expression of JAK2 and p-JAK2 was significantly increased. Transfection of miR-101 mimic significantly reduced the expression of JAK2 and p-JAK2 in Caski cells, reduced cell proliferation and increased cell apoptosis.

CONCLUSIONS

The decrease of miR-101 expression and the increase of JAK2 expression play a role in cervical cancer, while the increase of miR-101 expression can inhibit the proliferation and promote the apoptosis of cells by inhibiting the expression of JAK2.

Analysis of gene mutation associated with tyrosine kinase inhibitor sensitivity of epidermal growth factor receptor in cervical cancer patients

OBJECTIVE

Cervical cancer is frequent in females. Epidermal growth factor receptor has a prominent expression in certain malignant tumors. This study aims to observe the expressional profile of epidermal growth factor receptor (EGFR) in cervical cancer patients, and mutation of EGFR gene related with its sensitivity towards tyrosine kinase inhibitor.

MATERIALS AND METHODS

Cervical cancer patients from our hospital were recruited as the experimental group, in parallel with chronic cervicitis patients as control group. Serum EGFR level was measured by enzyme-linked immunosorbent assay (ELISA), and EGFR levels in cervical tissues were quantified by immunohistochemistry assay (IHC) staining. Real Time-PCR (RT-PCR) examined mutations of exon 18, 19, and 21 of the EGFR gene, to analyze their correlation with clinical or pathological features.

RESULTS

Serum EGFR in experimental group was 1.16 ± 0.04 ng/ml, significantly higher than control group (p < 0.05). EGFR positive rate was 71.1% in cancer tissues, significantly higher compared to controlled or adjacent tissues (p < 0.05). Mutation rats of EGFR exon 19 and exon 21 were 3.3% and 5%, respectively. No mutation was found in exon 18. Such mutations of EGFR gene were related with cancer differentiation grade, tumor-lymph-node-metastasis (TNM) stage, lymph node or distal metastasis (p < 0.05), but not age, Karnofsky performance score (KPS) score or infiltration depth.

CONCLUSIONS

EGFR is highly expressed in serum and tumors of cervical cancer patients, some of which showed mutations of exon 19 and 21 of EGFR gene with relatively lower frequency. Mutation rates were significantly higher in patients with highly differentiated grade, early TNM stage, and those without lymph node or distal metastasis.

Magnetic-Competition-Induced Colossal Magnetoresistance in n-Type HgCr_{2}Se_{4} under High Pressure

The n-type HgCr_{2}Se_{4} exhibits a sharp semiconductor-to-metal transition (SMT) in resistivity accompanying the ferromagnetic order at T_{C}=106  K. Here, we investigate the effects of pressure and magnetic field on the concomitant SMT and ferromagnetic order by measuring resistivity, dc and ac magnetic susceptibility, as well as single-crystal neutron diffraction under various pressures up to 8 GPa and magnetic fields up to 8 T. Our results demonstrate that the ferromagnetic metallic ground state of n-type HgCr_{2}Se_{4} is destabilized and gradually replaced by an antiferromagnetic, most likely a spiral magnetic, and insulating ground state upon the application of high pressure. On the other hand, the application of external magnetic fields can restore the ferromagnetic metallic state again at high pressures, resulting in a colossal magnetoresistance (CMR) as high as ∼ 3×10^{11}% under 5 T and 2 K at 4 GPa. The present study demonstrates that n-type HgCr_{2}Se_{4} is located at a peculiar critical point where the balance of competition between ferromagnetic and antiferromagnetic interactions can be easily tipped by external stimuli, providing a new platform for achieving CMR in a single-valent system.

Tuning the Distance to a Possible Ferromagnetic Quantum Critical Point in A_{2}Cr_{3}As_{3}

Although superconductivity in the vicinity of an antiferromagnetic (AFM) instability has been extensively explored in the last three decades or so, superconductivity in compounds with a background of ferromagnetic (FM) spin fluctuations is still rare. We report ^{75}As nuclear quadrupole resonance measurements on the A_{2}Cr_{3}As_{3} family, which is the first group of Cr-based superconductors at ambient pressure, with A being alkali elements. From the temperature dependence of the spin-lattice relaxation rate (1/T_{1}), we find that by changing A in the order of A=Na, Na_{0.75}K_{0.25}, K, and Rb, the system is tuned to approach a possible FM quantum critical point (QCP). This may be ascribed to the Cr2-As2-Cr2 bond angle that decreases towards 90°, which enhances the FM interaction via the Cr2-As2-Cr2 path. Upon moving away from the QCP, the superconducting transition temperature T_{sc} increases progressively up to 8.0 K in Na_{2}Cr_{3}As_{3}, which is in sharp contrast to the AFM case where T_{sc} usually shows a maximum around a QCP. The 1/T_{1} decreases rapidly below T_{sc} with no Hebel-Slichter peak, and ubiquitously follows a T^{5} variation below a characteristic temperature T^{*}≈0.6 T_{sc}, which indicates the existence of point nodes in the superconducting gap function commonly in the family. These results suggest that the A_{2}Cr_{3}As_{3} family is a possible solid-state analog of superfluid ^{3}He.

Effect of hydrostatic pressure on the superconducting properties of quasi-1D superconductor K2Cr3As3

K₂Cr₃As₃ is a newly discovered quasi-1D superconductor with a T _c  =  6.1 K and an upper critical field µ ₀ H _c2(0)  ≈  40 T three times larger than the Pauli paramagnetic limit µ ₀ H _p that is suggestive of a spin-triplet Cooper pairing. In this paper, we have investigated the effects of hydrostatic pressure on its T _c and µ ₀ H _c2 by measuring the ac magnetic susceptibility χ'(T) under magnetic fields at various hydrostatic pressures up to 7.5 GPa. The major findings include: (1) T _c is suppressed gradually to below 2 K at 7.5 GPa; (2) the estimated µ ₀ H _c2(0) decreases dramatically to below µ ₀ H _p above ~2 GPa and becomes slight lower than the orbital limiting field [Formula: see text] estimated from the initial slope of upper critical field via [Formula: see text]  =  -0.73T _cdH _c2/[Formula: see text] in the clean limit; (3) the estimated Maki parameter α  =  √2[Formula: see text]/H _p drops from 4 at ambient pressure to well below 1 at P  >  2 GPa, suggesting the crossover from Pauli paramagnetic limiting to orbital limiting in the pair breaking process upon increasing pressure. These observations suggested that the application of hydrostatic pressure could drive K₂Cr₃As₃ away from the ferromagnetic instability and lead to a breakdown of the spin-triplet pairing channel. We have also made a side-by-side comparison and discussed the distinct effects of chemical and physical pressures on the superconducting properties of K₂Cr₃As₃.

Enhancement of radiation effect by Ginkgo biloba extract in C3H mouse fibrosarcoma

BACKGROUND AND PURPOSE

Ginkgo biloba leaf extract (GBE) is known to increase peripheral blood circulation. The hypothesis that GBE may be able to enhance radiosensitivity of tumor by improving tumor blood flow and thus decreasing hypoxic fraction was tested.

MATERIALS AND METHODS

Fibrosarcoma (FSaII) growing in C3H mouse leg muscle was used as a tumor model. GBE was given i.p. 1 h before irradiation with or without priming dose given 1 day earlier. Effect on tumor and normal tissue radiation reaction was investigated.

RESULTS

Tumor growth delay by radiation was more elongated after two doses (1-day interval) of GBE than after a single dose. Radiation dose for 3-day tumor growth delay was decreased from 12.45 (10.97-13.93) Gy to 6.06 (3.89-8.22) Gy by two doses of GBE [enhancement ratio = 2.06 (1.32-2.79)]. Hypoxic cell fraction was 10.6% (6.3-18.2%) for control, 7.2% (3.8-14.0%) after a single dose (P = 0.18) and 2.7% (1.5-5.0%) after two doses (P < 0.001). Radiation effect on normal tissue, estimated by acute skin reaction and jejunal crypt assay, was not affected by GBE.

CONCLUSION

Ginkgo biloba extract enhances radiation effect on tumor without increasing acute normal tissue radiation damage in this model system probably by increasing tumor blood flow and further investigation for this possible radiosensitizer is needed.