Gui-Long Guo

Upregulation of CD44v6 contributes to acquired chemoresistance via the modulation of autophagy in colon cancer SW480 cells

The CD44 isoform containing variant exon v6 (CD44v6) plays an important role in the progression, metastasis, and prognosis of colorectal cancer (CRC). Recently, it was found that CD44v6 is involved in acquired drug resistance. This study aimed to investigate the molecular mechanism of CD44v6 in the resistance of CRC cells to chemotherapy. A stable CD44v6 overexpression model in SW480 cells was established via lentiviral transduction. The chemosensitivity of cells to 5-fluorouracil (5-FU) and oxaliplatin (L-OHP) was determined by cell counting kit (CCK)-8, lactate dehydrogenase (LDH) release, and colony formation assays. Immunohistochemical staining of CD44v6 was performed in human CRC tissues. The key components in cell apoptosis, drug efflux and metabolism, mismatch repair, autophagy, epithelial–mesenchymal transition (EMT), and the PI3K–Akt and MAPK–Ras–Erk1/2 pathways were assessed using flow cytometry, quantitative real-time polymerase chain reaction (PCR), and western blot assays. The CD44v6 overexpression cells showed a higher viability, a lower LDH release rate, and an increased clonogenicity than the control cells under drug treatment. Moreover, overexpression of CD44v6 resulted in enhanced autophagy flux, EMT, and phosphorylation of Akt and Erk in the presence of drugs. Furthermore, high CD44v6 expression in the primary tumor was closely associated with an early recurrence in CRC patients who underwent curative surgery and adjuvant chemotherapy. In conclusion, overexpression of CD44v6 contributes to chemoresistance in SW480 cells under cytotoxic stress via the modulation of autophagy, EMT, and activation of the PI3K–Akt and MAPK–Ras–Erk pathways.

Preoperative platelet to lymphocyte ratio is a valuable prognostic biomarker in patients with colorectal cancer.

Objectives Recent studies suggest that an elevated preoperative platelet to lymphocyte ratio (PLR) may be considered a poor prognostic biomarker in patients with colorectal cancer (CRC). The aim of this study was to evaluate the prognostic impact of PLR in patients with CRC. Methods We enrolled 1314 patients who underwent surgery for CRC between 2005 and 2011. Preoperative PLR level was stratified into quintiles for Kaplan-Meier analysis and multivariable Cox proportional hazard regression models. Results Higher PLR quintiles were significantly associated with poorer overall survival (P = 0.002). Multivariate analysis showed that PLR was an independent risk factor for overall survival (OS) (P = 0.034). Patients in PLR quintile 5 had lower overall survival than in quintile 1 (hazard ratio (HR) = 1.701, 95% confidence interval (CI): 1.267–2.282, P < 0.001). Although patients in PLR quintile 5 had significantly lower disease-free survival (DFS) than in quintile 1 (HR = 1.522, 95% CI: 1.114–2.080, P = 0.008), this association was not significant after multivariable adjustment (P = 0.075). In the subgroup analysis, PLR remained an independent factor in terms of advanced tumor stage (III, IV), male sex, carcinoembryonic antigen (≤ 5 ng/ml), age (> 65 years) and body mass index (≤ 25) (P < 0.05 for all measurements). The results remained unchanged when the PLR was analyzed as a dichotomous variable by applying different cut-off values of 150, 185, 220. Conclusions Elevated preoperative PLR was independently associated with an increased risk of mortality in patients with CRC. The utility of PLR may help to improve prognostic predictors.

Nonalcoholic fatty liver disease: a negative risk factor for colorectal cancer prognosis.

AbstractNonalcoholic fatty liver disease (NAFLD) is known to be associated with an increased risk of colorectal cancer (CRC). However, the relationship between NAFLD and the prognosis of CRC remains unclear. The primary objective of this study was to evaluate the overall survival (OS) and disease-free survival (DFS) rates in patients with CRC and the secondary objective was to compare clinicopathologic variables which were stratified by NAFLD.We performed a large cohort study of 1314 patients who were first diagnosed with CRC between January 2006 and April 2011. Postoperative follow-up data were collected from out-patient medical records, telephone consultations, and social security death indices. The Kaplan–Meier method was used to calculate the cumulative survival rate. Clinicopathologic variables were analyzed by univariate analysis and multivariate analysis through a Cox proportional hazard regression model.The mean follow-up time was 52.7 ± 25.3 months. Upon baseline comparison, the NAFLD group had significantly higher values of body mass index, triglycerides, and uric acid and significantly lower values of high-density lipoprotein, compared with the non-NAFLD group (P < 0.05 for all). There were no significant differences between the 2 groups with regard to tumor location, TNM staging, tumor differentiation, carcinoembryonic antigen, and vascular invasion. The cumulative 1-, 3-, and 5-year OS rates were 96.1%, 85.2%, and 80.6%, respectively, in the NAFLD group, which were statistically significantly higher than the OS rates of 91.6%, 76.2%, and 67.8%, respectively, in the non-NAFLD group (P = 0.075, P = 0.002, P = 0.030, respectively). There was no difference in DFS rates between the CRC patients with and without NAFLD (P = 0.267). Multivariate analysis showed that the presence of NAFLD was an independent negative risk factor for OS after adjusting for clinicopathologic covariates (hazard ratio = 0.593; 95% confidence interval 0.442, 0.921; P = 0.020), but not for DFS (P = 0.270).NAFLD may play a protective role in OS for CRC patients. Further studies are needed to elucidate the molecular mechanisms of putative protective effects in CRC patients with NAFLD.

Impact of platelet to lymphocyte ratio and metabolic syndrome on the prognosis of colorectal cancer patients

Objective The aim of this study was to evaluate the prognostic value of both platelet to lymphocyte ratio (PLR) and metabolic syndrome (MetS) in colorectal cancer (CRC) patients. Patients and methods We retrospectively enrolled 1,163 CRC patients. Preoperative values of PLR were stratified into three groups according to cut-off values of 120 and 220. The Kaplan–Meier analysis was used to calculate cumulative survival rate related to PLR and MetS. Cox proportional hazard regression models were used to analyze potential risk factors and the prognosis associated with PLR and MetS in CRC patients. Results PLR was significantly higher in the MetS(+) group as compared to MetS(−) group (P=0.039). An elevated PLR was significantly associated with mortality (P=0.014), but not the existence of MetS (P=0.235). In multivariate regression analysis, PLR was an independent risk factor for overall survival (OS) (P=0.046). For the subgroup with a PLR >220, MetS was an independent predictor for both OS and disease-free survival (P=0.039 and P=0.047, respectively) by multivariate analysis adjusting for confounding covariates. In addition, the presence of MetS was associated with a 2-fold increased risk of mortality and tumor recurrences (hazard ratio [HR] =2.0 and HR =1.9, P<0.05, respectively). Conclusion Preoperative PLR was associated with MetS in CRC patients. Testing for the combined presence of PLR and MetS could potentially improve the predictive accuracy of CRC prognosis.

(S)-crizotinib induces apoptosis in human non-small cell lung cancer cells by activating ROS independent of MTH1

BackgroundNon–small cell lung cancer (NSCLC) accounts for approximately 80–85% of all lung cancers and is usually diagnosed at an advanced stage with poor prognosis. Targeted therapy has produced unprecedented outcomes in patients with NSCLC as a number of oncogenic drivers have been found. Crizotinib, a selective small-molecule inhibitor, has been widely used for the treatment of NSCLC patients with ALK gene rearrangements. A recent study has also shown that (S)-enantiomer of crizotinib exhibits anticancer activity by targeting the protein mutT homologue (MTH1). Since this discovery, contradictory studies have cast a doubt on MTH1 as a therapeutic target of (S)-crizotinib.MethodsNCI-H460, H1975, and A549 cells and immunodeficient mice were chosen as a model to study the (S)-crizotinib treatment. The changes induced by (S)-crizotinib treatment in cell viability, apoptosis as well as ROS, and endoplasmic reticulum stress pathway in the cells were analyzed by MTT assay, FACSCalibur, Western blotting, ROS imaging and electron microscopy.ResultsHere, we report that MTH1 does not affect survival of NSCLC cells. We found that (S)-crizotinib induces lethal endoplasmic reticulum stress (ER) response in cultured NSCLC cells by increasing intracellular levels of reactive oxygen species (ROS). Blockage of ROS production markedly reversed (S)-crizotinib-induced ER stress and cell apoptosis, independent of MTH1. We confirmed these findings in NSCLC xenograft studies and showed that (S)-crizotinib-induced ER stress and cell apoptosis.ConclusionsOur results reveal a novel antitumor mechanism of (S)-crizotinib in NSCLC which involves activation of ROS-dependent ER stress apoptotic pathway and is independent of MTH1 inhibition.

Prognostic Value of Chemotherapy-Induced Neutropenia at the First Cycle in Invasive Breast Cancer.

AbstractChemotherapy-induced neutropenia (CIN) was the most apparent side effects of bone marrow suppression with adjuvant chemotherapy. Recently, several studies revealed that CIN may predict better outcomes. However, the researches upon breast cancer were still indefinite.We reviewed the female patients with pathologically diagnosed invasive breast cancer at the First Affiliated Hospital of Wenzhou Medical University, between Jan 2008 and Dec 2010. The lowest neutrophil counts in the second week after the first cycle of chemotherapy were collected. Clinicopathological characteristics and survival rates were compared and analyzed between the CIN group and non-CIN group.The median follow-up time was 62 months. The differences of over-all survival and local recurrence-free survival between the 2 groups were nonsense (P = 0.938, P = 0.695, respectively). But the disease-free survival and distant metastasis-free survival of the CIN group were statically significantly better (HR = 0.391, P = 0.009, and HR = 0.315, P = 0.005, respectively). The bone metastasis-free survival may be responsible for the differences (HR = 0.469, P = 0.005). Subgroup analyses showed the CIN may predict lower bone metastases rates with ER positive status, premenopause or younger age (⩽ 40) (P = 0.002, P = 0.004, and P = 0.0001, respectively). Cox analysis showed younger ages, N staging, and the presence of CIN were associated with bone metastasis-free survival independently adjusting to peritumoral vascular invasion (P < 0.05).CIN may predict a decreased recurrence risk of breast cancer, especially bone metastases.

The Clinical Relevance of Psammoma Body and Hashimoto Thyroiditis in Papillary Thyroid Carcinoma: A Large Case-control Study.

AbstractThis study aims to investigate the impact of psammoma body (PB) on papillary thyroid carcinoma (PTC), and evaluate the association among PB, Hashimoto thyroiditis (HT), and other clinicopathologic characteristics in PTC patients.We conducted a retrospective case-control study involving 1052 PTC patients who underwent total thyroidectomy or lobectomy with lymph node dissection.Psammoma body was observed in 324 out of 1052 PTC (30.8%) patients. Ultrasonographic (US) calcification (P < 0.001), multifocality of the tumor (P = 0.047), lymph node metastasis (LNM) (P < 0.001), HT (P < 0.001), and Primary tumor (T), Regional lymph nodes (N), Distant metastasis (M) staging (P = 0.001) were significantly related to the presence of PB. The presence of PB was significantly associated with US microcalcification (P < 0.001). In the subgroup with HT, compared with the patients without PB, the patients with PB exhibited a higher frequency of central LNM (54.7% vs 32.1%; P < 0.001) and US microcalcification (94.7% vs 38.8%; P < 0.001), as well as smaller tumors (0.9 ± 0.6 vs 1.3 ± 0.9 cm; P < 0.001). In the subgroup without HT, the patients with PB displayed a higher incidence of lateral LNM (25.8% vs 14.6%; P < 0.001), US microcalcification (87.3% vs 52.5%; P < 0.001), and extrathyroidal extension (47.2% vs 34.8%; P = 0.001), as well as larger tumors (1.3 ± 0.9 vs 1.0 ± 0.8 cm; P < 0.001) than without PB. Moreover, in the subgroup with PB, the PTC patients with HT showed a higher LNM (77.9% vs 57.2%; P < 0.001) and a lower frequency of extrathyroidal extension (20.0% vs 47.2%; P < 0.001) than without HT.Psammoma body is a useful predictor of aggressive tumor behavior in PTC patients. HT with PB shows more aggressive behaviors than non-HT with PB in PTC patients.

Schisandrin B exhibits potent anticancer activity in triple negative breast cancer by inhibiting STAT3

ABSTRACT Triple negative breast cancer (TNBC) is an aggressive subgroup of human breast cancer. In this study, we have examined the potential of Schisandrin B (Sch B), a bioactive chemical compound found in Schisandra chinensis, against TNBC. We used MDA‐MB‐231, BT‐549, and MDA‐MB‐468 TNBC cells and immunodeficient mice to study the effect of Sch B. Our results show that Sch B inhibits TNBC growth by inducing cell cycle arrest and by triggering apoptotic death. Sch B also inhibited the migration and colony formation of tumor cells, and prevented the growth of TNBC cells in mice. We found that these inhibitory activities were mediated through suppression of signal transducer and activator of transcription‐3 (STAT3) phosphorylation and nuclear translocation. Taken together, our studies show that Sch B has potent anti‐tumor activity against TNBC via a novel mechanism involving STAT3 inactivation. HighlightsSchisandrin B exhibits potent anticancer activity in TNBC.Schisandrin B inhibits STAT3 in TNBC.Schisandrin B can be a potential new therapeutic agent for the management of TNBC.

A mono-carbonyl analog of curcumin induces apoptosis in drug-resistant EGFR-mutant lung cancer through the generation of oxidative stress and mitochondrial dysfunction

Introduction Targeted therapies using epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC) patients harboring EGFR mutations, leading to the approval of gefitinib and erlotinib as standard first-line clinical treatment. Inevitably, a considerable proportion of patients develop resistance to EGFR-TKIs due to the acquisition of secondary mutations within EGFR. Therefore, alternative strategies to target NSCLC are desperately needed. Materials and methods In this study, we have evaluated the effect of a reactive oxygen species (ROS)-inducing agent WZ35, a mono-carbonyl analog of curcumin, to target an inherent biological property of cancer cells, increased oxidative stress. To study whether WZ35 can inhibit NSCLC tumorigenesis, we used gefitinib- and erlotinib-resistant cell line H1975. Results In this study, we show that WZ35 treatment dramatically decreases cell viability and induces apoptosis in H1975 cells through the generation of ROS. We also found that the antitumor activity of WZ35 involved ROS-mediated activation of the endoplasmic reticulum stress pathway and mitochondrial dysfunction. Furthermore, WZ35 significantly inhibited H1975 xenograft tumor growth through the inhibition of cell proliferation and induction of apoptosis. Discussion These findings show that WZ35 may be a promising candidate for the treatment of EGFR-TKI-resistant NSCLC.

Novel allylated monocarbonyl analogs of curcumin induce mitotic arrest and apoptosis by reactive oxygen species-mediated endoplasmic reticulum stress and inhibition of STAT3

Curcumin is a promising active compound from a natural source and is extensively being tested in clinical trials because of its bio-functional properties. However, poor bioavailability has hampered its clinical application. Numerous attempts have been made in our laboratory to discover analogs of curcumin with enhanced bioavailability and superior pharmacological activity. In this study, we have investigated a new series of allylated monocarbonyl analogs of curcumin (MAC) and tested their effect on gastric cancer cells. Our results show six MAC that selectively targeted cancer cell lines to inhibit growth and induce apoptosis. This activity was achieved by generation of reactive oxygen species (ROS) by MAC. We selected one effective MAC (CA10) for further investigation and show that CA10 inhibits cell growth by causing G2/M cell cycle arrest and induction of apoptotic death. CA10 induced ROS generation and subsequent activation of endoplasmic reticulum (ER) stress and inhibition of signal transducer and activator of transcription 3 (STAT3) phosphorylation, inhibits cancer cell proliferation. These anti-tumor activities of CA10 were confirmed in gastric cancer xenografts. CA10 induced ROS, activated the ER stress pathway and inhibited STAT3 phosphorylation and gastric xenografts tumor growth in mice. Our studies provide experimental evidence that MAC CA10 effectively targets gastric cancer in preclinical models by enhancing ROS and ROS-mediated signaling.