Establishment of highly invasive pancreatic cancer cell lines and the expression of IL-32

Role of interleukin‑32 in cancer progression (Review)

Interleukin (IL)-32 is induced by pro-inflammatory cytokines and promotes the release of inflammatory cytokines. Therefore, it can promote inflammatory responses. The present review article summarized the role of the receptors required for IL-32 action, the biological function of IL-32 and its mechanism of action in tumors. Moreover, it assessed the significance of aberrant IL-32 expression in associated diseases and analyzed the effects of IL-32 on four key types of cancer: Colorectal, gastric, breast and lung. However, the mechanism of action of IL-32 needs to be further demonstrated by assessing the role of this cytokine in cancer to elucidate novel and reliable targets for future cancer treatments.

SPARC accelerates biliary tract cancer progression through CTGF-mediated tumor-stroma interactions: SPARC as a prognostic marker of survival after neoadjuvant therapy

PURPOSE

In biliary tract cancer (BTC), malignancy is strongest at the invasion front. To improve the BTC prognosis, the invasion front should be controlled. We evaluated tumor-stroma crosstalk at the tumor center and at the invasion front of BTC lesions. We investigated the expression of SPARC, a marker of cancer-associated fibroblasts, and determined its ability to predict BTC prognosis after neoadjuvant chemoradiotherapy (NAC-RT).

METHODS

We performed immunohistochemistry to evaluate SPARC expression in resected specimens from patients that underwent BTC surgery. We established highly invasive (HI) clones in two BTC cell lines (NOZ, CCLP1), and performed mRNA microarrays to compare gene expression in parental and HI cells.

RESULTS

Among 92 specimens, stromal SPARC expression was higher at the invasion front than at the lesion center (p = 0.014). Among 50 specimens from patients treated with surgery alone, high stromal SPARC expression at the invasion front was associated with a poor prognosis (recurrence-free survival: p = 0.033; overall survival: p = 0.017). Coculturing fibroblasts with NOZ-HI cells upregulated fibroblast SPARC expression. mRNA microarrays showed that connective tissue growth factor (CTGF) was upregulated in NOZ-HI and CCLP1-HI cells. A CTGF knockdown suppressed cell invasion in NOZ-HI cells. Exogeneous CTGF upregulated SPARC expression in fibroblasts. SPARC expression at the invasion front was significantly lower after NAC-RT, compared to surgery alone (p = 0.003).

CONCLUSION

CTGF was associated with tumor-stroma crosstalk in BTC. CTGF activated stromal SPARC expression, which promoted tumor progression, particularly at the invasion front. SPARC expression at the invasion front after NAC-RT may serve as a prognosis predictor.

Predictive Value of MUC5AC Signature in Pancreatic Ductal Adenocarcinoma: A Hypothesis Based on Preclinical Evidence

Mucin 5AC (MUC5AC) glycoprotein plays a crucial role in carcinogenesis and drug sensitivity in pancreatic ductal adenocarcinoma (PDAC), both individually and in combination with other mucins. Its function and localization are glycoform-specific. The immature isoform (detected by the CLH2 monoclonal antibody, or mab) is usually in the perinuclear (cytoplasmic) region, while the mature (45 M1, 2-11, Nd2) variants are in apical and extracellular regions. There is preclinical evidence suggesting that mature MUC5AC has prognostic and predictive (response to treatment) value. However, these findings were not validated in clinical studies. We propose a MUC5AC signature with three components of MUC5AC-localization, variant composition, and intensity-suggesting a reliable marker in combination of variants than with individual MUC5AC variants alone. We also postulate a theory to explain the occurrence of different MUC5AC variants in abnormal pancreatic lesions (benign, precancerous, and cancerous). We also analyzed the effect of mature MUC5AC on sensitivity to drugs often used in PDAC management, such as gemcitabine, 5-fluorouracil, oxaliplatin, irinotecan, cisplatin, and paclitaxel. We found preliminary evidence of its predictive value, but there is a need for large-scale studies to validate them.

IL-32 and its Paradoxical Role in Neoplasia

Interleukin-32 (IL-32) is an interleukin cytokine usually linked to inflammation. In recent years, it has been found that IL-32 exhibits both pro- and anti-tumor effects. Although most of those effects from IL-32 appear to favor tumor growth, some isoforms have shown to favor tumor suppression. This suggests that the role of IL-32 in neoplasia is very complex. Thus, the role of IL-32 in these various cancers and protein pathways makes it a very crucial component to consider when looking at potential therapeutic options in tumor treatment. In this review, we will explore what is currently known about IL-32, including its relationship with tumorigenesis and the potential for IL-32 to enhance local and systemic anti-tumor immune responses. Such a study might be helpful to accelerate the development of IL-32-based immunotherapies.

A Paradoxical Effect of Interleukin-32 Isoforms on Cancer

IL-32 plays a contradictory role such as tumor proliferation or suppressor in cancer development depending on the cancer type. In most cancers, it was found that the high expression of IL-32 was associated with more proliferative and progression of cancer. However, studying the isoforms of IL-32 cytokine has placed its paradoxical role into a wide range of functions based on its dominant isoform and surrounding environment. IL-32β, for example, was found mostly in different types of cancer and associated with cancer expansion. This observation is legitimate since cancer exhibits some hypoxic environment and IL-32β was known to be induced under hypoxic conditions. However, IL-32θ interacts directly with protein kinase C-δ reducing NF-κB and STAT3 levels to inhibit epithelial-mesenchymal transition (EMT). This effect could explain the different functions of IL-32 isoforms in cancer. However, pro- or antitumor activity which is dependant on obesity, gender, and age as it relates to IL-32 has yet to be studied. Obesity-related IL-32 regulation indicated the role of IL-32 in cancer metabolism and inflammation. IL-32-specific direction in cancer therapy is difficult to conclude. In this review, we address that the paradoxical effect of IL-32 on cancer is attributed to the dominant isoform, cancer type, tumor microenvironment, and genetic background. IL-32 seems to have a contradictory role in cancer. However, investigating multiple IL-32 isoforms could explain this doubt and bring us closer to using them in therapy.

Oxidative Stress Markers Are Associated with a Poor Prognosis in Patients with Pancreatic Cancer

Pancreatic cancer is a malignancy of rising prevalence, especially in developed countries where dietary patterns and sedentariness favor its onset. This malady ranks seventh in cancer-related deaths in the world, although it is expected to rank second in the coming years, behind lung cancer. The low survival rate is due to the asymptomatic course of the early stages, which in many cases leads to metastases when becoming evident in advanced stages. In this context, molecular pathology is on the way towards finding new approaches with biomarkers that allow a better prognosis and monitoring of patients. So the present study aims to evaluate a series of molecular biomarkers, PARP1, NOX1, NOX2, eNOS and iNOS, as promising candidates for prognosis and survival by using immunohistochemistry. The analysis performed in 41 patients with pancreatic cancer showed a correlation between a high expression of all these components with a low survival rate, with high statistical power for all. In addition, a 60-month longitudinal surveillance program was managed, accompanied by several clinical parameters. The derivative Kaplan–Meier curves indicated a low cumulative survival rate as well. Ultimately, our research emphasized the value of these molecules as survival-associated biomarkers in pancreatic cancer, offering new gates for clinical management.

Application of Proteomics in Pancreatic Ductal Adenocarcinoma Biomarker Investigations: A Review

Pancreatic ductal adenocarcinoma (PDAC), a highly aggressive malignancy with a poor prognosis is usually detected at the advanced stage of the disease. The only US Food and Drug Administration-approved biomarker that is available for PDAC, CA 19-9, is most useful in monitoring treatment response among PDAC patients rather than for early detection. Moreover, when CA 19-9 is solely used for diagnostic purposes, it has only a recorded sensitivity of 79% and specificity of 82% in symptomatic individuals. Therefore, there is an urgent need to identify reliable biomarkers for diagnosis (specifically for the early diagnosis), ascertain prognosis as well as to monitor treatment response and tumour recurrence of PDAC. In recent years, proteomic technologies are growing exponentially at an accelerated rate for a wide range of applications in cancer research. In this review, we discussed the current status of biomarker research for PDAC using various proteomic technologies. This review will explore the potential perspective for understanding and identifying the unique alterations in protein expressions that could prove beneficial in discovering new robust biomarkers to detect PDAC at an early stage, ascertain prognosis of patients with the disease in addition to monitoring treatment response and tumour recurrence of patients.

Interleukin-32 regulates downstream molecules and promotes the invasion of pancreatic cancer cells

Pancreatic cancer is a malignant neoplasm with high invasiveness and poor prognosis. In a previous study, a highly invasive pancreatic cancer cell line was established and found to feature enhanced interleukin-32 (IL-32) expression. However, whether IL-32 promotes the invasiveness by enhancing or suppressing the expression of IL-32 through regulating downstream molecules was unclear. To investigate the effect of IL-32, cells were established with high levels of expression or downregulated IL-32; their invasive ability was measured using a real-time measurement system and the expression of some candidate downstream molecules involved in invasion was evaluated in the two cell types. The morphological changes in both cell types and the localization of IL-32 expression in pancreatic cancer tissues were studied using immunohistochemistry. Among the several splice variants of IL-32, cells transfected with the ε isoform had increased invasiveness, whereas the IL-32-suppressed cells had reduced invasiveness. Several downstream molecules, whose expression was changed in the two cell types, were monitored. Notably, changes of E-cadherin, CLDN1, CD44, CTGF and Wnt were documented. The morphologies of the two cell types differed from the original cell line. Immunohistochemically, the expression of IL-32 was observed only in tumor cells and not in normal pancreatic cells. In conclusion, IL-32 was found to promote the invasiveness of pancreatic cancer cells by regulating downstream molecules.