Organoid models derived from patients with malignant phyllodes tumor of the breast

PURPOSE

Phyllodes tumor of the breast is a kind of rare neoplasm, which accounts for less than 1% of all breast tumors. Malignant phyllodes tumor (MPT) is the highest risk subtype of phyllodes tumor, and is characterized by the tendency of local recurrence and distant metastasis. The prediction of prognosis and the individual therapy for MPT is still challenging. It's urgent to develop a new reliable in vitro preclinical model in order to understand this disease better and to explore appropriate anticancer drugs for individual patients.

METHODS

Two surgically resected MPT specimens were processed for organoid establishment. MPT organoids were subsequently subjected to H&E staining, immunohistochemical analysis and drug screening, respectively.

RESULTS

We successfully established two organoid lines from different patients with MPT. The MPT organoids can well retain the histological features and capture the marker expression in original tumor tissues, including p63, vimentin, Bcl-2, CD34, c-Kit, and Ki-67, even after a long-term culture. The dose titration tests of eight typical chemotherapeutic drugs (paclitaxel, docetaxel, vincristine, doxorubicin, cisplatin, gemcitabine, cyclophosphamide, ifosfamide) on the two MPT organoid lines showed patient-specific drug responses and varying IC₅₀ values. Of all the drugs, doxorubicin and gemcitabine showed the best anti-tumor effect on the two organoid lines.

CONCLUSION

Organoids derived from MPT may be a novel preclinical model for testing personalized therapies for patients with MPT.

[Determination of methylmercury in urine by direct mercury analyzer]

Objective: To develop asolvent extraction-direct mercury analyzer method for determination of methylmercury in urine. Methods: After the urinehydrolyzesd by hydrobromic acid, methylmercury was extracted by tolueneand reverse-extracted from L-cysteine solution, it was then detectedbydirect mercuryanalyzer. Results: The linear range was 0.2-50.0 μg/L, and the related coefficient was 0.9999. The relative standard deviations (RSD) within the group were 5.04%-6.64%, and the RSD between the group were 5.65%-8.11 %. The average recovery efficiencies were 85.4%-95.5%. The detection limitation was 0.0482 μg/L and the quantification concentrations was 0.1607 μg/L. Conclusion: The method, which has low detection limit, high sensitivity, easy to operate, is stability for the determination of methylmercury in urine.

Multiplexed evaluation of immunity against SARS-CoV-2 variants using surface enhanced fluorescence from a nanostructured plasmonic chip

Generated by the immune system post-infection or through vaccination, the effectiveness of antibodies against emerging SARS-CoV-2 variants is crucial for protecting individuals from the COVID-19 pandemic. Herein, a platform for the multiplexed evaluation of SARS-CoV-2 neutralizing antibodies against various variants was designed on the basis of near-infrared (NIR) surface enhanced fluorescence by nano-plasmonic gold chip (pGOLD). Antibody level across variants (Wild-type, Alpha, Beta, Delta, Omicron) was confirmed by the sera from recovered-individuals who were unvaccinated and had infected with Wild-type, Delta, Omicron variants. However, the neutralizing activity against Omicron variant was markedly decreased for individuals infected by Wild-type (~ 5.6-fold) and Delta variant (~ 19.1-fold). To the opposite, neutralizing antibody from individuals recovered from Omicron variant infection showed weak binding strength against non-Omicron variants. Antibody evolution over time was studied with individuals 196-530 days post Wild-type infection. Decreasing IgG antibody titer accompanied by increasing IgG binding avidity with elongated post-infection period were observed for the sera from Wild-type recovered-individuals with different post-infection times, suggesting that after the primary infection, a great number of antibodies were generated and then gradually decreased, while the antibody matured over time. By comparing the IgG level of individuals vaccinated for 27-51 days with individual post-infection, we found that ca. 1 month after two doses of vaccination, the antibody level was comparable to that of 500 days post-infection, and vaccination could enhance IgG avidity more efficiently. This work demonstrated a platform for the multiplexed, high-throughput and rapid screening of acquired immunity against SARS-CoV-2 variants, providing a new approach for the analysis of vaccine effectiveness, immunity against emerging variants, and related serological study.