Endoplasmic Reticulum Stress Promotes Autophagy and Apoptosis and Reduces Chemotherapy Resistance in Mutant p53 Lung Cancer Cells.

BACKGROUND/AIMS: Lung cancer (LC) continues to be one of the most prevalent cancers around the world. During this study we aimed to investigate the involvement of endoplasmic reticulum stress (ERS) in autophagy, apoptosis, and chemotherapy resistance of mutant p53 LC cells. METHODS: Immunohistochemistry was employed to help determine the p53 mutation status of cancer cells from 92 primary LC patients, who were subsequently assigned to either the mutant p53 (n = 39) or wild-type p53 group (n = 53). RESULTS: Mutant p53 cells exhibited increased expression of the C/EBP homologous protein (CHOP), glucose-regulated protein 78 (GRP78), and inositol-requiring enzyme-1α (IRE1α). The Mutant p53 cells were also found to be sensitive to chemotherapy and displayed decreased expression of PI3K, Akt, and mTOR. The mutant p53 cell lines were treated with tunicamycin to induce ERS and rapamycin in order to inhibit mTOR. Both agents increased the expression of CHOP, GRP78, IRE1α, LC3-II/LC3-I, Atg5, Atg7, caspase-3, caspase-12, cleaved caspase-3, cleaved caspase-12, as well as decreases in cell proliferation as well as the expression levels of PI3K, Akt, and mTOR. Enhanced levels of cell apoptosis and reduced chemotherapy resistance were also detected. CONCLUSION: The findings of our study suggest that ERS promotes autophagy and apoptosis, while acting to reduce chemotherapy resistance in mutant p53 LC cells by downregulating the PI3K/Akt/mTOR signaling pathway.

TUSC3 induces autophagy in human non-small cell lung cancer cells through Wnt/ß-catenin signaling.

We investigated the effects of tumor suppressor candidate 3 (TUSC3) on autophagy in human non-small cell lung cancer (NSCLC) cells. A total of 118 NSCLC patients (88 males and 30 females) who underwent surgery at our institute were enrolled in the study. Immunohistochemical analysis revealed that TUSC3 protein expression was lower in NSCLC specimens than adjacent normal tissue. Correspondingly, there was greater methylation of TUSC3 in NSCLC than adjacent normal tissue. After transient transfection of A549 NSCLC cells with constructs designed to up-regulate or down-regulate TUSC3 expression, we analyzed the effects of inhibiting the Wnt pathway (XAV939) and autophagy (chloroquine, CQ) on the behavior of NSCLC cells. We also performed TOP/FOP-Flash reporter assays, MTT assays, Annexin V-FITC/propidium iodide staining, and acridine orange staining to evaluate Wnt/ß-catenin signaling, cell proliferation, apoptosis, and autophagy, respectively. Expression of Wnt/ß-catenin pathway components and autophagy-related proteins was analyzed using qRT-PCR and Western blotting. We found that TUSC3 inhibited cell proliferation and promoted both apoptosis and autophagy in A549 cells. In addition, TUSC3 increased expression of autophagy-related proteins. It also increased expression of Wnt/ß-catenin signaling pathway components and promoted nuclear transfer of ß-catenin, resulting in activation of Wnt/ß-catenin signaling. TUSC3 thus induces autophagy in human NSCLC cells through activation of the Wnt/ß-catenin signaling pathway.

Pretreatment of Shaoyao Gancao Decoction () alters pharmacokinetics of intravenous paclitaxel in rats.

OBJECTIVE: To investigate the effect of Shaoyao Gancao Decoction (, SGD) on the pharmacokinetics of intravenously administered paclitaxel in rats. METHODS: Paclitaxel was intravenously administered to rats (3 mg/kg) with or without the concomitant administration of SGD (752 mg/kg, a single day or 14 consecutive days pretreatment). The paclitaxel in the serum was quantified using a simple and rapid ultra performance liquid chromatography (UPLC) method for the pharmacokinetic study. The pharmacokinetic parameters were calculated via a non-compartment model using the computer program DAS 2.0. RESULTS: The pharmacokinetic parameters of paclitaxel were significantly altered in response to 14 consecutive days of pretreatment with SGD. The area under the curve (AUC0-t, from 4 820±197 to 4 205±186 ng·mL-1·-1) and AUC0-∞ (from 5 237±280 to 4 514±210 ng·mL-1·-1) significantly decreased in response to the 14-day pretreatment with SGD. The values of Vdss (L/kg) were 10.74±1.08 and 9.35±0.49, those of CL (L/kg) were 0.67±0.03 and 0.57±0.03 and the t1/2 (h) values were 11.17±0.84 and 11.32±0.93, respectively, for the 14-day SGD pretreatment and intravenous paclitaxel alone. The AUC0-t and AUC0-∞ values decreased by 13% and 14% (P<0.01), respectively. The area under the curve decreased signifificantly (P<0.01), and the total clearance increased by 1.2-fold (P<0.01), after 14 consecutive days of pretreatment with SGD. A single-day pretreatment with SGD did not signifificantly affect the pharmacokinetic parameters of paclitaxel. CONCLUSIONS: SGD administration for 14 consecutive days increased the metabolism of paclitaxel, while a 1-day pretreatment had little effect. The results would contribute important information to the study on interaction between Chinese medicines and chemotherapy and also help to utilize SGD better in the adjunctive therapy of cancer patients.

ALDH1A1 mediates resistance of diffuse large B cell lymphoma to the CHOP regimen.

Although there have been substantial advances in our knowledge of the resistance of diffuse large B cell lymphoma (DLBCL) to chemotherapy, there are few efficient treatment strategies for recurrent/refractory DLBCL. The aim of this study was to investigate the role of aldehyde dehydrogenase (ALDH) 1A1 in the resistance of diffuse large B cell lymphoma to the chemotherapeutic mixture consisting of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP). The involvement of ALDH1A1 in DLBCL was elucidated by knockdown and pharmacologic inhibition; Cell Counting Kit-8 (CCK-8) and clone formation assays were used to determine its role in CHOP sensitivity and clone formation ability. Caspase colorimetric assay was used to measure the extent of apoptosis. Western blot analysis was used to measure signal transducer and activator of transcription 3 (STAT3)/nuclear factor kappa B (NF-κB) signaling proteins, and quantitative real-time PCR (RT-PCR) was used to measure the differential expression of ALDH1A1 of DLBCL patients and healthy donors. ALDH1A1 showed a 5.64-fold higher expression in malignant B cells than in normal B cells. Diethylaminobenzaldehyde (DEAB) decreased the half maximal inhibitory concentration (IC50) of the CHOP regimen in Farage cells from 344.78 ± 65.75 to 183.88 ± 49.75 ng/ml (P = 0.004). Both knockdown and inhibition of ALDH1A1 reduced clonogenicity, increased caspase-3/caspase-9 activity, and attenuated the phosphorylation status of STAT3/NF-κB. The prognosis of patients with a high level of ALDH1A1 expression was poor compared with that of patients with low levels of expression (P = 0.044). ALDH1A1 is a new mediator for resistance of DLBCL to CHOP; it is a predictor of clinical prognosis and may serve as a potential target to improve chemotherapy responsiveness of human DLBCL.

[Myoepithelial carcinoma of salivary glands: a clinical analysis of 13 cases].

PURPOSE: This study retrospectively analyzed the clinical data of 13 patients with myoepithelial carcinoma of salivary glands for improving the accuracy of diagnosis and treatment outcome. METHODS: Thirteen cases with myoepithelial carcinoma of the salivary glands in Xiangya Hospital from January 1992 to September 2010 were reviewed, including the clinical biological behavior, diagnosis,treatment and prognosis. RESULTS: Thirteen patients included 6 men and 7 women, aged from 14 to 71 years (median 40 years).The tumor occurred predominantly in the parotid gland (53.8%).Among the 13 cases,7 were clinically misdiagnosed as benign tumors and 2 were misdiagnosed pathologically. All cases underwent operation. Two cases received surgery plus adjuvant chemotherapy; five cases underwent surgery plus adjuvant radiotherapy. 4(30.8%) had cervical lymph node metastasis and 2 cases(15.4%) developed distant metastasis. Follow-up time ranged from 3 months to 6 years. Six cases died of local recurrence or distal metastasis. CONCLUSIONS: Myoepithelial carcinoma of the salivary glands is a rare tumor. The diagnosis is depended on histology and immunohistochemistry. The tumor has a high rate of distant metastasis and high rate of lymph node metastasis in T3 to T4 cases. Radical surgery is the treatment of choice. Elective neck dissection should be considered in T3 to T4 cN0 cases. The effect of chemotherapy and radiotherapy needs to be investigated.