Huiyu Yuan

Secretory expression of heterologous protein in Kluyveromyces cicerisporus.

To explore the potential of heterologous protein expression in Kluyveromyces cicerisporus, three expression plasmids, pUK1-PIT, pUKD-PIT and pUKD-S-PIT, based on the vector pUK1 or pUKD were constructed and transformed, respectively, into yeast strain K. cicerisporus Y179U. Human interferon α-2a, used as an example protein, was successfully expressed and secreted by transformant Y179U/pUKD-PIT and Y179U/pUKD-S-PIT. In the flask culture, strain Y179U/pUKD-S-PIT could express interferon at 60 mg/l. The stability of plasmid pUKD-S-PIT in the host was higher than that of pUKD-PIT. This was consistent with their expression levels of interferon. There were two interferon-related bands found by Western blotting analysis. The possible reason for this is discussed.

The assessment of estrogen receptor status and its intratumoral heterogeneity in patients with breast cancer by using 18F-fluoroestradiol PET/CT

Aim The aim of this study was to investigate the clinical value of 18F-fluoroestradiol (18F-FES) PET/CT in the assessment of the estrogen receptor (ER) and its intratumoral heterogeneity in breast cancer patients. Methods Forty-six female patients (50 lesions) with histologically confirmed invasive breast cancer who underwent both 18F-FES and 18F-FDG PET/CT in our center were retrospectively included. All the patients enrolled were scheduled to undergo biopsy. The 18F-FES and FDG uptakes were compared with pathological features (tumor size, ER, progesterone receptor, human epidermal growth factor receptor 2, and Ki67%). The optimal threshold to discriminate ER-positive and ER-negative lesions was determined by receiver operating characteristic curve analysis. Furthermore, we observed the intratumoral heterogeneity by a heterogeneity index (SUVmax/SUVmean) and compared the results with the Chang-Gung Image Texture Analysis. Results There was good agreement between 18F-FES uptake and ER, progesterone receptor, and human epidermal growth factor receptor 2 expression (P < 0.001), and the use of SUVmean instead of SUVmax can provide a slightly better correlation. The optimal threshold for 18F-FES PET/CT to discriminate between ER-positive and ER-negative lesions, as determined by receiver operating characteristic curve analysis, was an SUVmax of 1.82 (sensitivity = 88.2% and specificity = 87.5%) and SUVmean of 1.21 (sensitivity = 85.3% and specificity = 93.7). Our simplified heterogeneity index–FES can easily observe ER heterogeneity. In addition, our results suggested that recurrent/metastatic patients and lesions located other than breast might have greater heterogeneity. Conclusions 18F-FES PET/CT is a feasible, noninvasive method for assessing ER expression in breast cancer patients. Because intratumoral heterogeneity exists, 18F-FES PET/CT might better reflect the ER expression, especially in metastatic patients after treatment, thus assisting in making individualized treatment decisions.

The significant value of predicting prognosis in patients with colorectal cancer using 18F-FDG PET metabolic parameters of primary tumors and hematological parameters

ObjectsThe purpose was to evaluate the correlation of the pre-treatment hematological parameters with metabolic parameters of primary tumor in baseline 18F-FDG PET/CT in patients with colorectal cancer (CRC) and estimate the prognostic value of both.MethodsWe retrospectively investigated 231 patients with CRC who underwent baseline 18F-FDG PET/CT. Routine blood sampling was tested in the same term. PET parameters in term of hematological parameters and pathological characteristics of primary tumor were compared. Kaplan–Meier survival analysis was performed in the patients without distant metastasis. The differences of disease-free survival between groups were compared by log-rank tests.ResultsNeutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were significantly correlated with all the metabolic parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV) and tumor lesion glycolysis (TLG). The patients with NLR > 3 had higher MTV (24.82 ± 18.16 vs 19.06 ± 13.30, P = 0.039) and TLG (219.04 ± 186.94 vs 166.45 ± 146.39, P = 0.047) than those whose NLR ≤ 3. NLR in those patients with distant metastasis was significantly higher than those without distant metastasis (P = 0.018) while LMR in those patients with distant metastasis was significantly lower than those without distant metastasis (P = 0.032). Survival analysis showed that those patients with low MTV (P = 0.015), low NLR (P = 0.008) and high LMR (P = 0.027) revealed significant survival benefit.ConclusionsThere was a significant association between the pre-treatment hematological parameters and metabolic parameters of baseline 18F-FDG PET/CT in the patients with CRC. It might be helpful in those patients with high NLR and low LMR to undergo 18F-FDG PET/CT to detect distant metastasis and predict prognosis.