ATF4 renders human T-cell acute lymphoblastic leukemia cell resistance to FGFR1 inhibitors through amino acid metabolic reprogramming.

Abnormalities of FGFR1 have been reported in multiple malignancies, suggesting FGFR1 as a potential target for precision treatment, but drug resistance remains a formidable obstacle. In this study, we explored whether FGFR1 acted a therapeutic target in human T-cell acute lymphoblastic leukemia (T-ALL) and the molecular mechanisms underlying T-ALL cell resistance to FGFR1 inhibitors. We showed that FGFR1 was significantly upregulated in human T-ALL and inversely correlated with the prognosis of patients.

Deficiency of Tfh Cells and Germinal Center in Deceased COVID-19 Patients.

The COVID-19 pandemic caused by SARS-CoV2 is characterized by a remarkable variation in clinical severity ranging from a mild illness to a fatal multi-organ disease. Understanding the dysregulated human immune responses in the fatal subjects is critical for management of COVID-19 patients and the pandemic. In this study, we examined the immune cell compositions in the lung tissues and hilar lymph nodes using immunohistochemistry on 6 deceased COVID-19 patients and 4 focal organizing pneumonia (FOP) patients who underwent lung surgery and served as controls.

[Expression of fatty acid synthase and its association with HER2 in invasive ductal carcinoma of breast].

Objective: To investigate the expression of fatty acid synthase (FAS) in adenosis, atypical ductal epithelial hyperplasia, ductal carcinoma in situ (DCIS) and invasive ductal carcinoma (IDC) of breast, and the correlation of FAS expression with HER2 gene amplification in IDC.

Methods: Immunohistochemical EnVision method staining for FAS was performed in 100 cases of breast lesions and 10 normal breast tissues. HER2 gene amplification was detected with FISH in 60 cases of IDC.

[Effect of hypoxia on the chemotherapeutic sensitivity of human ovarian cancer cells to paclitaxel and its mechanism].

Objective: To explore the effect of hypoxia and hypoxia-inducible factor-1alpha (HIF-1alpha) on the expression of multidrug resistance gene-1 (mdr-1) and its coded p-glyeoprotein (P-gp) as well as the chemotherapeutic sensitivity of human ovarian cancer cells to paclitaxel and its mechanism.

Methods: The mRNA and protein levels of HIF-1alpha, mdr-1 and p-gp were studied by immunocytochemistry, semiquantitative reverse transcription-ploymerase chain reaction (RT-PCR) and Western blot analysis in human ovarian cancer cells (A2780) in 5% CO2 + 1% O2 hypoxic culture and 21% O2 normoxic culture, respectively. Methyl thiazolyl tetrazolium (MIT) was used to evaluate the chemotherapeutic sensitivity of A2780 cells to paclitaxel by inhibition rate.

[The role of myocardin in hypoxia-induced transdifferentiation of pulmonary artery endothelial cells into smooth muscle-like cells].

Objective: To investigate the transdifferentiation of pulmonary artery endothelial cells (PAECs) into smooth muscle-like cells under hypoxia and the role of myocardin therein.

Methods: Recombinant plasmid psimyocardin (pSi), capable of silencing the expression of myocardin gene, was constructed by RNAi to be used to transfect the PAECs. Endothelial cells of adult pig pulmonary small arteries were purified by immunomagnetic purification technique, and divided into 4 groups: normoxia group (to be cultured in normoxic cell culture box containing 21% O(2), 5% CO2, and 74% N(2)), normoxia + pSi group, hypoxia group (to be cultured in cell box containing 1% O(2), 5% CO2, and 74% N(2)), and hypoxia + pSi group to be cultured for 1, 4, and 7 days respectively.

Cigarette smoke extract inhibits the proliferation of alveolar epithelial cells and induces apoptosis.

Cigarette smoke extract (CSE) contains abundant oxidants and free radicals. Oxidative stress caused by cigarette smoking results in the destruction of the alveolar cell walls and emphysema. However, there exists discrepancy about how CSE works in the process.

[Impact of hypoxia on taxol-induced apoptosis in human ovarian cancer cell line A2780 and its mechanism].

Background & Objective: Hypoxia, a feature and important living microenvironment of solid tumors, might be related to drug-resistance of tumors. This study was to establish a hypoxic model of ovarian cancer cell line A2780, and to investigate impacts of hypoxia and hypoxia inducible factor-1alpha (HIF-1alpha) on Taxol-induced apoptosis in A2780 cells.

Methods: Cobalt chloride (CoCl(2)), a chemical hypoxia inducer, was added in A2780 cells to develop a hypoxic model.