Ricerc@Sapienza

Present research aims to collect a series of results applicable in the battle against cancers of hepato-biliary-pancreatic system, which are characterized by high aggressiveness, resistance to chemotherapy and poor prognosis. Recent evidence suggests that chemoresistance occurs because of a complex network involving many cell alterations, including metabolic changes, aberrant activation of survival and growth signalings, and overexpression of membrane transporters. Along with difficulties to achieving effective treatments, many anticancer regimens produce severe side effects, thus hindering the continuation of therapy. To overcome these drawbacks, some innovative pharmacological regimens, among which drug combination, have been proposed. Besides the reduction of anticancer drug toxicity, drug combination allows the simultaneous blockage of distinct key molecules in oncogenic signalling network, thus affecting both primary pathways involved in cancer cell proliferation and the activation of specific deregulated mechanisms, which help the cell overcome the treatment injury. Searching for chemosensitizing agents has attracted great attention by researchers due to the interesting possible application of this strategy in adjuvant chemotherapy or in sensitizing resistant cancer cells. However, variability in cancer phenotype and the complex network carrying chemoresistance make difficult to identify an ideal mechanism to be targeted for counteracting its development.
Among different mechanisms, the overexpression of ABC transmembrane proteins has been widely investigated, although further studied are required to better define all the pump isoforms in cancer cells (especially in pancreatic and biliary cancers). Also, considering that efflux pumps control the normal detoxification from toxicants, a complete inhibition can induce severe side effects. This evidence strengthens the need of better characterizing the role of specific ABC transporter in liver, biliary and pancreatic cancer cells and the involved molecular pathways, in order to better design possible modulating interventions.
In this project, we propose to evaluate the ability of caryophyllane sesquiterpenes to target the HIF-1alpha/STAT3/Nrf2 axis, thus leading to a more articulated modulation of the hypoxia-induce metabolic reprogramming, activation of abnormal growth and metastasization, apoptosis inhibition, adaptation to oxidative stress and ABC transporter overexpression. Moreover, characterizing the role of HIF-1alpha/STAT3/Nrf2 axis and the specific ABC pumps for each tumour allows to identify possible biomarkers to be detected for supporting the choice of a targeted chemotherapy. The expected results will allow to better understand the molecular basis of the strong aggressiveness and chemoresistance of liver, biliary and pancreatic cancers, the possible similarity and differences in the mechanisms of carcinogenesis, due to the common endodermal origin followed by a specific differentiation, and to approach targeted preventive strategies to improve the prognosis of patients [5]. Also, highlighting the tolerability of tested combinations of chemosensitizers and anticancer drugs in noncancerous cells is an important goal as it allows to overcame common drawbacks of standard chemotherapy and can drive a further pharmacological interest for the tested sesquiterpenes.
Taken together, the results acquired within present research project could provide a new approach to overcome MDR phenomenon and consequently to improve the quality of life of patients by increasing the survival expectations.
Feasibility of this project is assured by the availability of adequate laboratory infrastructures for cell culturing and treatment, along with suitable instrumentation for spectrophotometric and fluorescence analysis, at Dept. of Physiology and Pharmacology V. Erspamer. Flow cytometer and western blotting equipments will be accessed within a collaboration with Dept. of Biochemical Sciences. Furthermore, a novel instrument for cell imaging, multimode reader and live-cell analysis will be soon available at Dept. of Physiology and Pharmacology V. Erspamer, thanks to a grant received from Sapienza University (PI Prof. Mazzanti). This instrument allows to perform rapid multi-sample analyses and simultaneous determinations in a short time, using low volumes and few manual manipulations, thus providing a powerful tool for obtaining reliable data with reduced time and costs. The possibility to work with small volumes also reduces reagent, cell and nutrient consumption, and optimizes the management of laboratory. This fully automated equipment is also supported by an incubator-like control system, which enables to work under both normoxia and hypoxia, and to acquire accurate quantitative and phenotypic data. Taken together, the automated, versatile, and well-integrated features of this instrument will strengthen the quality of our research.