[Evaluation of the predictive effect of PD-L1 expression on survival in early triple-negative breast cancer]

Objectives: To find the prognostic factors related to early triple-negative breast cancer to optimize the therapeutic strategies, and explore the influence of programmed cell death ligand-1(PD-L1)expression in early triple-negative breast cancer on its prognosis, so as to provide support for clinical treatment decisions. Methods: Early triple-negative breast cancer patients treated at the National Cancer Center, National Clinical Research Center for Cancer, Cancer Hospital, Chinese Academy of Medical Sciences during 1st June, 2009 and 31st Oct, 2015 were enrolled in this study. All the clinicopathological data of patients were collected, and the paraffin sections of the surgical specimens were stained with estrogen receptor, progesterone receptor, human epidermal growth factor receptor-2, secreted protein acidic and rich in cysteine (SPARC), androgen receptor, PD-L1 and other antibodies by the immunohistochemical method. Kaplan-Meier survival and Cox regression curves were used for survival analysis of relevant clinical and pathological results and nomogram survival prediction models were established to explore the influence of relevant factors on the prognosis. Results: A total of 205 patients with triple-negative breast cancer were enrolled. Ninety patients (43.9%) were PD-L1 positive. The median follow-up time was 63 months. Thirty-seven patients were relapsed or recurrent and 16 patients were dead. The 5-year disease-free survival (DFS) rate and overall survival (OS) rate were 86.1% (95% CI: 81.4%-90.8%) and 93.6% (95% CI: 91.0%-97.6%), respectively, in the general population. Univariate Cox regression analysis showed that PD-L1 expression and lymph node metastasis were correlated with DFS and OS (P<0.05). In multivariate analysis, PD-L1 expression was an independent influencing factor of DFS, with PD-L1 positive patients possessing a significant survival benefit in DFS (HR=0.31, 95% CI: 0.13-0.73). Lymph node metastasis was an independent influencing factor of OS, and OS was significantly shortened in patients with positive lymph node metastasis (HR=3.24, 95% CI: 1.15-9.17). PD-L1, lymph node metastasis, menopausal status, Ki-67 index and adjuvant chemotherapy regimen were included to establish the 1- and 3-year DFS and OS nomogram prediction models, resulting in C indices of 0.698 and 0.748, respectively. Conclusions: PD-L1 expression is a predictive biomarker of good prognostic factor in triple-negative breast cancer patients. DFS is significantly prolonged in PD-L1 positive patients and OS also shows a prolongation trend. The nomogram prognosis prediction models have reference values for adjuvant chemotherapy in this patient group.

[Evaluation of the efficacy and safety of combination of gemcitabine and nedaplatin for patients with HER-2 negative metastatic breast cancer]

Objective: To assess the therapeutic efficacy and safety of the gemcitabine combined with nedaplatin (GN) chemotherapy for metastatic human epidermal growth factor receptor-2 (HER-2) negative breast cancer patients. Methods: Forty-five patients with HER-2 negative recurrent metastatic breast cancer who had received prior adjuvant or neoadjuvant therapy with anthracycline and/or taxanes were enrolled. All the patients received GN regime from January 2014 to February 2019. The therapeutic efficacy was evaluated according to response evaluation criteria in solid tumors (RECIST) 1.1. The adverse response was evaluated and monitored according to common terminology criteria for adverse events (CTCAE). The progression-free survival (PFS) and overall survival (OS) and prognostic factors were also analyzed. Results: All of the 45 patients received 4 course GN, 1 of them achieved complete response, 21 achieved partial response. The objective response rate was 48.9 (95% CI: 33.7%-64.1%). Grade 3-4 hematological toxicities include leukopenia occurred in 10 (22.2%) of patients, neutropenia in 13 (28.9%) patients, and thrombocytopenia in 8 (17.6%) patients. The grade 3-4 hematological toxicities mainly manifested as nausea and vomiting, and the incidence was 4.4% (2/45). Among the 45 patients, 34 died, the median PFS was 5.1 (95% CI: 3.9-6.1) months and the median OS was 17.6 (95% CI: 13.1-20.9) months. Conclusion: The combination of gemcitabine and nedaplatin is an effective and tolerable treatment for metastatic breast cancer patients previously treated with anthracyclines and/or taxanes.

Antifungal activity of the bioactive substance from Bacillus atrophaeus strain HAB-5 and its toxicity assessment on Danio rerio

The prevalence of pathogen inhibitors bacteria has motivate the study for antimicrobial compounds. Bioactive fungicide have always received considerable attention. A bacterial isolated strain HAB-5 showed antifungal activity against plant fungi. Based on morphological, physiological, biochemical and 16SrDNA sequence analysis, the strain was identified to be a Bacillus atrophaeus. This strain possessed a broad spectrum antifungal activity against various plant pathogenic fungi. Extraction of antifungal substance was performed and the crude extract had potent antifungal ability and showed great potential for swelling and inhibiting spore germination. This antifungal displayed heat stability and active in a wide pH range 5.0-10.0. Moreover no reduction was found in its activity after enzyme treatment. The toxicity test was evaluated in Danio rerio. The acute toxicity test indicated that the 24, 48, 72, 96h LC₅₀ values of UMTLS to the zebrafish were 14.4, 13.8, 13.4, and 12.9%, respectively. Based on the results obtained in this study, antifungal substance was not toxic to zebra. Analyses of disease suppression showed that HAB-5 was effective to reduce the incidence of anthracnose symptoms on mango fruits, also prevent disease infection and protect tobacco seedling from Phytophtora nicotianae. The bioactive substance from Bacillus atrophaeus HAB-5 could be a candidate in the generation of new antifungal agents in crop.

Identification of lipopeptides produced by Bacillus subtilis Czk1 isolated from the aerial roots of rubber trees

We obtained a strain of Bacillus subtilis, which we named Czk1, from the aerial roots of rubber trees. This bacterial isolate exhibits strong antagonistic activity against Ganoderma pseudoferreum, Phellinus noxius, Helicobasidium compactum, Rigidoporus lignosus, Sphaerostilbe repens, and Colletotrichum gloeosporioides. Our earlier research has shown that the antagonistic activity of a fermentation supernatant Czk1 isolate produces a complex mixture of lipopeptides. In this study, we used methanol to extract crude lipopeptides, purified them using a Sephadex G-25 column, cloned the lipopeptide genes, and analyzed purified fractions by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF-MS) to identify the lipopeptides from B. subtilis strain Czk1. The cloned lipopeptide genes included those that encode the enzymes lpa, ituD, sfp, and fenB. The crude lipopeptides were purified and found in five fractions. Further analysis revealed that five fractions of the purified composition contained members of the surfactin, iturin, fengycin, and bacillomycin families of antibiotics. This suggests that these lipopeptides from strain Czk1 have potential as plant disease biocontrol agents.

Pythium vexans causing patch canker of rubber trees on Hainan Island, China

This is the first report of patch canker disease of rubber trees (clone RRIM600) in China. It is characterized by discrete irregular patches of rotted, discolored bark and wood, accompanied by a decrease in latex flow. A total of seven isolates of Pythium vexans were obtained from the diseased bark of the trunks and roots of rubber trees. Inoculating these isolates into healthy, mature rubber trees resulted in symptoms similar to patch canker and the same fungal species was re-isolated from the diseased tissues. This is also the first record of Py. vexans in Hainan.

[Antagonistic effects of dextromethorphan on vasoconstriction of phencyclidine in vitro]

Bioassay and spectrophotofluorometry were used to study the antagonistic effect of dextromethorphan (DM) on phencyclidine (PCP) vasoconstriction in rabbit ear artery. DM (5 mumols.L-1) antagonized enhancement of PCP, N-[1-(2-thienyl) cyclohexyl] piperidine (TCP) and dizocilpine maleate (MK-801) (5 mumols.L-1) on electrical stimulation-induced vasoconstriction by 86 +/- 18%, 84 +/- 17%, and 86 +/- 18%, respectively (n = 6, P less than 0.01), but had no obvious bioactivity itself at the same concentration. DM (1, 2.5, and 5 mumols.L-1) inhibited the PCP effect and reduced the maximal effect of PCP with pD2' = 5.3 +/- 0.3 (n = 4). The contents of norepinephrine (NE) in control, PCP, and DM + PCP groups were 5 +/- 6, 12 +/- 8, and 5 +/- 6 ng.ml-1, respectively (n = 9). PCP (10 mumols.L-1) increased the NE release (P less than 0.05) but DM (10 mumols.L-1) inhibited it (P less than 0.01). The results suggest DM may be a noncompetitive blockader for PCP receptors.