Research progress of circRNA as a biomarker of osteoporosis.

Osteoporosis, as a chronic metabolic bone disease, has the characteristic of insidious disease progression, which often leads to relatively delayed disease diagnosis. Therefore, early screening for osteoporosis has become a major public health challenge. The latest research indicates that circRNA is widely involved in the regulation of bone metabolism and is closely related to the occurrence and development of osteoporosis. Based on its high degree of sequence conservation and stability, circRNA has the potential to become a new clinical biomarker. The study of biomarkers is generally based on body fluid samples or adjacent tissue samples, with blood being the most commonly used, which can be divided into sources such as serum, plasma, peripheral blood monocytes, and plasma exosomes. Therefore, this article aims to review the research status of circRNA as a biomarker of osteoporosis.

Extensive Diversity and Prevalent Fluconazole Resistance among Environmental Yeasts from Tropical China.

Yeasts play important roles in both the environment and in human welfare. While some environmental yeasts positively contribute to nutrient cycling and food production, a significant number of yeast species are opportunistic human pathogens, including several that are tolerant/resistant to commonly used antifungal drugs. At present, most of our understanding of environmental yeasts has come from a few terrestrial environments in selected geographic regions. Relatively little is known about yeast diversity in tropical environments and their potential impacts on human health. Here, we characterize culturable yeasts in 968 environmental samples from eight regions in tropical China. Among the 516 soil, 273 freshwater, and 179 seawater samples, 71.5%, 85.7%, and 43.6% contained yeasts, respectively. A total of 984 yeast isolates were analyzed for their DNA barcode sequences and their susceptibilities to fluconazole. DNA sequence comparisons revealed that the 984 yeast isolates likely belonged to 144 species, including 106 known species and 38 putative novel species. About 38% of the 984 isolates belonged to known human pathogens and the most common species was Candida tropicalis, accounting for 21% (207/984) of all isolates. Further analyses based on multi-locus sequence typing revealed that some of these environmental C. tropicalis shared identical genotypes with clinical isolates previously reported from tropical China and elsewhere. Importantly, 374 of the 984 (38%) yeast isolates showed intermediate susceptibility or resistance to fluconazole. Our results suggest that these environmental yeasts could have significant negative impacts on human health.

MMP25-AS1/hsa-miR-10a-5p/SERPINE1 axis as a novel prognostic biomarker associated with immune cell infiltration in KIRC.

Long non-coding RNAs (lncRNAs) play a significant role in multiple human cancers as competing endogenous RNAs (ceRNAs). However, a systematic mRNA-microRNA (miRNA)-lncRNA network linked to kidney renal clear cell carcinoma (KIRC) prognosis has not been described. In this study, we aimed to identify the prognosis-related ceRNA regulatory network and analyzed its relationship with immune cell infiltration to predict KIRC patient survival. The MMP25-AS1/hsa-miR-10a-5p/SERPINE1 ceRNA network related to the prognosis of KIRC was obtained through bioinformatics analysis based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Meanwhile, we constructed a three-gene-based survival predictor model, which could be referential for future clinical research. Methylation analyses suggested that the abnormal upregulation of the SERPINE1 likely resulted from hypomethylation. Furthermore, the immune infiltration analysis showed that the MMP25-AS1/hsa-miR-10a-5p/SERPINE1 axis could affect the changes in the tumor immune microenvironment and the development of KIRC by affecting the expression of chemokines (CCL4, CCL5, CXCL13, and XCL2). Tumor Immune Dysfunction and Exclusion (TIDE) analysis indicated that the high expression of SERPINE1 might be related to tumor immune evasion in KIRC. In summary, the current study constructing the MMP25-AS1/hsa-miR-10a-5p/SERPINE1 ceRNA network might be a novel significant prognostic factor associated with the diagnosis and prognosis of KIRC.

In Situ Vitrification of Lung Cancer Organoids on a Microwell Array.

Three-dimensional cultured patient-derived cancer organoids (PDOs) represent a powerful tool for anti-cancer drug development due to their similarity to the in vivo tumor tissues. However, the culture and manipulation of PDOs is more difficult than 2D cultured cell lines due to the presence of the culture matrix and the 3D feature of the organoids. In our other study, we established a method for lung cancer organoid (LCO)-based drug sensitivity tests on the superhydrophobic microwell array chip (SMAR-chip). Here, we describe a novel in situ cryopreservation technology on the SMAR-chip to preserve the viability of the organoids for future drug sensitivity tests. We compared two cryopreservation approaches (slow freezing and vitrification) and demonstrated that vitrification performed better at preserving the viability of LCOs. Next, we developed a simple procedure for in situ cryopreservation and thawing of the LCOs on the SMAR-chip. We proved that the on-chip cryopreserved organoids can be recovered successfully and, more importantly, showing similar responses to anti-cancer drugs as the unfrozen controls. This in situ vitrification technology eliminated the harvesting and centrifugation steps in conventional cryopreservation, making the whole freeze-thaw process easier to perform and the preserved LCOs ready to be used for the subsequent drug sensitivity test.

Species Diversity and Antifungal Susceptibilities of Oral Yeasts from Patients with Head and Neck Cancer.

PURPOSE: To investigate the colonization and susceptibility to antifungal drugs of oral yeasts in head and neck cancer patients in Hainan, China. METHODS: Oral mucosa samples from 211 head and neck cancer patients were collected. Oral yeasts were isolated and identified to species by rDNA ITS sequencing. The susceptibilities of all yeasts to amphotericin B, fluconazole, fluorocytosine, itraconazole, and ketoconazole were determined. RESULTS: Yeasts were isolated from 124 of the 211 oral swabs. The 124 yeast isolates were classified into following 10 species, from the most frequent to the least frequent, Candida albicans (53.2%), Candida tropicalis (22.6%), Candida krusei (6.5%), Kodamaea ohmeri (5.6%), Candida parapsilosis (4.8%), Hanseniaspora opuntiae (2.4%), Candida metapsilosis (1.6%), Pichia terricola (1.6%), Pichia norvegensis (0.8%), and Trichosporon asahii (0.8%). The overall frequencies of resistance among the yeasts to amphotericin B, fluconazole, flucytosine, itraconazole, and ketoconazole were 4.8%, 8.1%, 16.1%, 9.7%, and 9.7%, respectively. One C. albicans strain and one C. tropicalis strain were tolerant/resistant to all five drugs. CONCLUSION: Given the high prevalence of oral yeast colonization in head and neck cancer patients and the observed resistance of certain yeast isolates to the five antifungal drugs, our results suggest that rapid identification and susceptibility testing should be implemented before antifungal treatment is applied among patients with head and neck cancer in Hainan.

Lung cancer organoids analyzed on microwell arrays predict drug responses of patients within a week.

While the potential of patient-derived organoids (PDOs) to predict patients' responses to anti-cancer treatments has been well recognized, the lengthy time and the low efficiency in establishing PDOs hamper the implementation of PDO-based drug sensitivity tests in clinics. We first adapt a mechanical sample processing method to generate lung cancer organoids (LCOs) from surgically resected and biopsy tumor tissues. The LCOs recapitulate the histological and genetic features of the parental tumors and have the potential to expand indefinitely. By employing an integrated superhydrophobic microwell array chip (InSMAR-chip), we demonstrate hundreds of LCOs, a number that can be generated from most of the samples at passage 0, are sufficient to produce clinically meaningful drug responses within a week. The results prove our one-week drug tests are in good agreement with patient-derived xenografts, genetic mutations of tumors, and clinical outcomes. The LCO model coupled with the microwell device provides a technically feasible means for predicting patient-specific drug responses in clinical settings.

Relationship between expression of CXCR7 and NF-κB in breast cancer tissue and occurrence of breast cancer and lymphatic metastasis.

It is designed to discuss the relationship between the expression of chemokine receptor 7 (chemokine receptor 7, CXCR7) and nuclear transcription factor-κB (nuclear factor kappa B, NF-κB) and the occurrence of the breast cancer and lymphatic metastasis. METHOD: 80 samples were excised and confirmed as breast cancer through our hospital pathology from January 2014 to December 2016 and tumor tissues and normal mammary tissues 2 cm from the tumor edges were taken as an experimental group and a control group, respectively. The method of immunohistochemical is utilized to test the expression of CXCR7 and NF-κB in the breast cancer tissue, compared with the para-carcinoma tissue, and analyze its relevance with the clinicopathologic features of the breast cancer tissue, such as tumor size, TNM staging, lymphatic metastasis and other conditions. RESULTS: both CXCR7 and NF-κB were highly expressed in the breast cancer tissue, the positive rate was significantly higher that that of paracancerous normal tissues, and the difference was statistically significant. And the expressions of CXCR7 and NF-κB were related to TNM staging of the breast cancer and lymphatic metastasis and unrelated to the tumor size, age, and expressions of ER, PR and HER2. CONCLUSION: both CXCR7 and NF-κB are related to the malignant grade of the breast cancer and lymphatic metastasis, which may be regarded as in important indicator to judge the prognosis of the breast cancer and be expected to be the new target of curing part of the breast cancer.

High-throughput superhydrophobic microwell arrays for investigating multifactorial stem cell niches.

Understanding the complex regulatory network that determines stem cell fates requires a high-throughput platform that can generate a large number of precisely controlled microenvironments representing multiple factors for stem cell culture and analysis. Here, we developed a superhydrophobic microwell array chip on which the culture conditions in each microwell can be spontaneously isolated by a grafted layer of superhydrophobic polymers. Simple steps for medium exchange were developed to facilitate the on-chip culture of both adherent and non-adherent cells for up to six days without compromising cell viability and functionality. The culture conditions in each microwell were facilely manipulated using a robotic spotter. Stem cell niches combining soluble factors, extracellular matrices and microtopographic cues were generated on a single 512-well SMARchip and their combinatorial effects on the fate of mouse Oct4-EGFP iPSCs were systematically probed. We observed significant differences in iPSC pluripotency and proliferation between adherent flat and suspended spherical cultures on our platform, which might provide insights into improvement of stem cell technologies.