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Background: Multidrug resistance (MDR) is one of the reasons for treatment failure in oral squamous cancer patients; however, the MDR mechanisms remain elusive.Methods: Two human oral squamous cell carcinoma (OSCC) cell lines, CAL27 and SCC9, were analyzed by stepwise selection upon exposure to 5-fluorouracil (5-FU) and cisplatin (CDDP) for MDR cell line establishment, and cell viability was analyzed by CCK8 assays. Transcriptomes of the CAL27 and CAL27-MDR cells were analyzed by RNA-seq assay. The molecules in Sonic hedgehog (Shh) signal pathway and MDR related pathway were selected for validation by qRT-PCR and Western blot. Human OSCC tissues were applied for immunohistochemical and clinicopathological analysis.Results: The OSCC-MDR cell lines with resistance to 5-FU and CDDP were successfully established. Protein expression levels of ATP-binding cassette (ABC) transporter ABCC1 and ABCG2 were increased 1.6-fold and 2.1-flod, respectively, in OSCC specimen from the patients with chemotherapy. The RNA-seq assay speculated the activation of Hedgehog (Hh) signaling with the upregulation of SHH, PTCH1, and SMO in OSCC-MDR cells as compared with OSCC cells. Furthermore, immunohistochemical studies confirmed that the high expression of SHH, PTCH1, and SMO in OSCC patients was significantly associated with chemotherapy. Overexpression of SHH increased the chemoresistance in OSCC cells, while the mRNA expression levels of PTCH1 and ABCG2 were increased in OSCC cells upon stimulation with recombinant SHH protein.Conclusions: These results revealed that the activation of Hh signaling pathway regulating ABC transporters is associated MDR in OSCC. [ABSTRACT FROM AUTHOR]

This paper makes a research on the relationship between TFT transmittance and white color uniformity, which based on 1st ITO process optimization. The results show that the better TFT transmittance uniformity leads to better white color uniformity, and the ITO oxidation is an important factor for TFT transmittance uniformity improvement. Annealing and increase oxygen flow during ITO sputtering when annealing is skipped are both the effective methods to obtain an excellent white color uniformity. [ABSTRACT FROM AUTHOR]

Cancer heterogeneity has been proposed to be one of the main causes of metastatic dissemination and therapy failure. However, the underlying mechanisms of this phenomenon remain poorly understood. Melanoma is an aggressive malignancy with a high heterogeneity and metastatic potential. Therefore, the present study investigated the possible association between cancer heterogeneity and metastasis in melanoma. In total, two novel Chinese oral mucosal melanoma (COMM) cell lines, namely COMM‑1 and COMM‑2, were established for exploring methods into preventing the loss of cellular heterogeneity caused by long‑term cell culture. Each cell line was grown under two different models of culture, which yielded two subtypes, one exhibited an adhesive morphology (COMM‑AD), whereas the other was grown in suspension (COMM‑SUS). Compared with the COMM‑AD cells, the COMM‑SUS cells exhibited higher metastatic capacities and autofluorescence. Further investigations indicated that the COMM‑SUS cells exhibited metabolic reprogramming by taking up lactate produced by COMM‑AD cells at increased levels to accumulate NADH through monocarboxylate transporter 1, whilst also increasing NADPH levels through the pentose phosphate pathway (PPP). Additionally, increased NADH and NADPH levels in the COMM‑SUS cells, coupled with the upregulation of the anti‑ferroptotic proteins, glutathione peroxidase 4 and ferrop-tosis suppressor protein 1, enabled them to resist ferroptotic cell death induced by oxidative stress during hematogenous dissemination. The inhibition of ferroptosis was found to substantially increase the metastatic capacity of COMM‑AD cells. Furthermore, suppressing lactate uptake and impairing PPP activation significantly decreased the metastatic potential of the COMM‑SUS cells. Thus, the present study on metabolic heterogeneity in COMM cells potentially provides a novel perspective for exploring this mechanism underlying cancer metastasis.