Retraction notice regarding several articles published in Tumor Biology

The publisher and the Editor-in-Chief, in consultation with former publisher of Tumor Biology, retract a total of 15 articles from the journals’ online catalog. The articles were published in different issues of the journal during the period 2014–2016. All articles affected by this retraction notice have problems related to image manipulation or misuse. A detailed explanation is given for each retracted article. The investigations were carried out in accordance with the recommendations of the Committee on Publication Ethics (COPE).

Effect of pentoxifylline on colon cancer patients treated with chemotherapy (Part I)

BACKGROUND: Cancer progression is associated with significant systemic clinical manifestations including cachexia induced weight loss and anorexia. Pentoxifylline (PTX) is a drug that has been shown to have multiple beneficial effects in cancer patients through its anti-inflammatory properties. MAIN OBJECTIVE: To evaluate PTX effects on colon cancer patients treated with chemotherapy. PATIENTS and METHODS: Forty metastatic colon cancer patients receiving chemotherapy were enrolled in this randomized study. 17 patients were treated with a full dose of PTX (400 mg TID), 9 patients with a reduced dose PTX (200 mg TID) and 23 served as controls (no PTX). RESULTS: Follow-up evaluations of patients included the following: physical examination; leukopenia determination; weight determination; stomatitis determination; and survival rate. Patients treated with PTX (both full and reduced doses), experienced a significant increase in weight and a reduction in stomatitis relative to the control group. Treatment with PTX also significantly increased patient survival rate. All patients treated with PTX, had a median overall survival (OS) rate of 20.4 months as compared to 13.2 months in the control group. CONCLUSIONS: PTX treatment of colon cancer patients, in addition to chemotherapy, significantly improved survival rates, induced weight gain and reduced stomatitis occurrence –all important parameters of cachexia.

Analysis of serum HE4 levels in various histologic subtypes of epithelial ovarian cancer and other malignant tumors

BACKGROUND: The measurement of serum HE4 levels has emerged as a sensitive and specific biomarker for epithelial ovarian cancers (EOCs). However, serum levels in women diagnosed with various histologic subtypes of EOC and in women with metastatic non-ovarian primary malignancies have not been widely reported. OBJECTIVE: The goal of this study was to identify how serum HE4 levels vary in women diagnosed with different histologic subtypes of EOC and non-ovarian malignancies. METHODS: Data from six prospective pelvic mass clinical trials was combined and an evaluation of serum HE4 levels in women diagnosed with a malignancy was performed. For all patients, serum was obtained prior to surgery and final pathology, including primary tumor site, histologic subtype, grade and stage, were recorded. The mean, median, standard deviation, maximum, and minimum HE4 levels were determined for each group. RESULTS: A total of 984 patients were included in this study, with the average patient age being 60 years old. There were 230 premenopausal and 754 postmenopausal patients. Serum HE4 levels were elevated (≥70.0 pMol) in 85%of EOCs, 40%of LMP tumors, 21%of non-EOCs (germ cell tumors), 25%of cervical cancers, and 47%of non-gynecologic metastatic cancers. Analysis of histologic subtypes revealed 90%(n = 391) of serous, 85%(n = 73) of endometrioid, 45%(n = 42) of mucinous, 86%(n = 51) of mixed tumors, and 69%(n = 36) of clear cell tumors had elevated serum HE4 levels. CONCLUSIONS: Serum HE4 levels are most often elevated in women with high grade serous and endometrioid EOCs, and though serum elevations are seen more often with advanced stage disease, HE4 is also often elevated in early stage disease and lower grade tumors.

Effects of in vitro short- and long-term treatment with telomerase inhibitor in U-251 glioma cells

BACKGROUND: The inhibition of the enzyme telomerase (TERT) has been widely investigated as a new pharmacological approach for cancer treatment, but its real potential and the biochemical consequences are not totally understood. OBJECTIVE: Here, we investigated the effects of the telomerase inhibitor MST-312 on a human glioma cell line after both short- and long-term (290 days) treatments. METHODS: Effects on cell growth, viability, cell cycle, morphology, cell death and genes expression were assessed. RESULTS: We found that short-term treatment promoted cell cycle arrest followed by apoptosis. Importantly, cells with telomerase knock-down revealed that the toxic effects of MST-312 are partially TERT dependent. In contrast, although the long-term treatment decreased cell proliferation at first, it also caused adaptations potentially related to treatment resistance and tumor aggressiveness after long time of exposition. CONCLUSIONS: Despite the short-term effects of telomerase inhibition not being due to telomere erosion, they are at least partially related to the enzyme inhibition, which may represent an important strategy to pave the way for tumor growth control, especially through modulation of the non-canonical functions of telomerase. On the other hand, long-term exposure to the inhibitor had the potential to induce cell adaptations with possible negative clinical implications.

Identification of interleukin-16 production on tumor aggravation in hepatocellular carcinoma by a proteomics approach

BACKGROUND: Cytokines play an important role in the immune response, angiogenesis, cell growth, and differentiation in hepatocellular carcinoma (HCC). OBJECTIVE: We performed a comprehensive study to identify tumor-related cytokines and pathways involved in HCC pathogenesis. METHODS: Cytokine production was evaluated in human HCC tissues and adjacent non-tumor tissues using an antibody-based protein array technique. We compared cytokine expression in HCC tissues with that of hepatic hemangioma (HH), liver metastasis of colorectal cancer, and noncancerous liver tissues from transplantation donors. The protein levels and localization of the candidate cytokines were analyzed by western blotting and immunohistochemistry. RESULTS: Increased expression of interleukin (IL)-1 receptor antagonist, macrophage migration inhibitory factor, and IL-16 was observed in HCC and paired adjacent non-tumor tissues compared with noncancerous livers. In addition, there were increased IL-16 levels in HCC tissues compared with HH. IL-16 treatment significantly increased cell proliferation in vitro. The expression of extracellular signal-regulated kinase (ERK)1/2 and cyclin D1 was markedly increased in cells from two HCC cell lines, Huh7 and HepG2, in a dose- and time-dependent manner. Phosphorylated to total ERK1/2 ratio was increased in Huh7 cells following IL-16 50 ng/ml, but not HepG2 cells. ERK phosphorylation have occurred earlier than protein accumulation at 48 h. Pretreatment with the ERK inhibitor, FR18024, or an anti-IL-16 antibody reduced the increase in IL-16 production in HCC cells. CONCLUSIONS: These results suggest that cell proliferation induced by IL-16 is mediated through the ERK pathway, thus, we identified a new factor associated with HCC tumor growth.

Seeding metastases: The role and clinical utility of circulating tumour cells

Peripheral human blood is a readily-accessible source of patient material in which circulating tumour cells (CTCs) can be found. Their isolation and characterization holds the potential to provide prognostic value for various solid cancers. Enumeration of CTCs from blood is becoming a common practice in informing prognosis and may guide therapy decisions. It is further recognized that enumeration alone does not capture perspective on the heterogeneity of tumours and varying functional abilities of the CTCs to interact with the secondary microenvironment. Characterizing the isolated CTCs further, in particular assessing their functional abilities, can track molecular changes in the disease progress. As a step towards identifying a suite of functional features of CTCs that could aid in clinical decisions, developing a CTC isolation technique based on extracellular matrix (ECM) interactions may provide a more solid foundation for isolating the cells of interest. Techniques based on size, charge, density, and single biomarkers are not sufficient as they underutilize other characteristics of cancer cells. The ability of cancer cells to interact with ECM proteins presents an opportunity to utilize their full character in capturing, and also allows assessment of the features that reveal how cells might behave at secondary sites during metastasis. This article will review some common techniques and recent advances in CTC capture technologies. It will further explore the heterogeneity of the CTC population, challenges they experience in their metastatic journey, and the advantages of utilizing an ECM-based platform for CTC capture. Lastly, we will discuss how tailored ECM approaches may present an optimal platform to capture an influential heterogeneous population of CTCs.