Immunoprophylactic and immunotherapeutic control of hormone receptor-positive breast cancer.

Hormone receptor (HR)+ breast cancer (BC) causes most BC-related deaths, calling for improved therapeutic approaches. Despite expectations, immune checkpoint blockers (ICBs) are poorly active in patients with HR+ BC, in part reflecting the lack of preclinical models that recapitulate disease progression in immunocompetent hosts. We demonstrate that mammary tumors driven by medroxyprogesterone acetate (M) and 7,12-dimethylbenz[a]anthracene (D) recapitulate several key features of human luminal B HR+HER2- BC, including limited immune infiltration and poor sensitivity to ICBs. M/D-driven oncogenesis is accelerated by immune defects, demonstrating that M/D-driven tumors are under immunosurveillance. Safe nutritional measures including nicotinamide (NAM) supplementation efficiently delay M/D-driven oncogenesis by reactivating immunosurveillance. NAM also mediates immunotherapeutic effects against established M/D-driven and transplantable BC, largely reflecting increased type I interferon secretion by malignant cells and direct stimulation of immune effector cells. Our findings identify NAM as a potential strategy for the prevention and treatment of HR+ BC.

Immunogenic stress and death of cancer cells: Contribution of antigenicity vs adjuvanticity to immunosurveillance.

Cancer cells are subjected to constant selection by the immune system, meaning that tumors that become clinically manifest have managed to subvert or hide from immunosurveillance. Immune control can be facilitated by induction of autophagy, as well as by polyploidization of cancer cells. While autophagy causes the release of ATP, a chemotactic signal for myeloid cells, polyploidization can trigger endoplasmic reticulum stress with consequent exposure of the "eat-me" signal calreticulin on the cell surface, thereby facilitating the transfer of tumor antigens into dendritic cells. Hence, both autophagy and polyploidization cause the emission of adjuvant signals that ultimately elicit immune control by CD8+ T lymphocytes. We investigated the possibility that autophagy and polyploidization might also affect the antigenicity of cancer cells by altering the immunopeptidome. Mass spectrometry led to the identification of peptides that were presented on major histocompatibility complex (MHC) class I molecules in an autophagy-dependent fashion or that were specifically exposed on the surface of polyploid cells, yet lost upon passage of such cells through immunocompetent (but not immunodeficient) mice. However, the preferential recognition of autophagy-competent and polyploid cells by the innate and cellular immune systems did not correlate with the preferential recognition of such peptides in vivo. Moreover, vaccination with such peptides was unable to elicit tumor growth-inhibitory responses in vivo. We conclude that autophagy and polyploidy increase the immunogenicity of cancer cells mostly by affecting their adjuvanticity rather than their antigenicity.

Coffee induces autophagy in vivo.

Epidemiological studies and clinical trials revealed that chronic consumption coffee is associated with the inhibition of several metabolic diseases as well as reduction in overall and cause-specific mortality. We show that both natural and decaffeinated brands of coffee similarly rapidly trigger autophagy in mice. One to 4 h after coffee consumption, we observed an increase in autophagic flux in all investigated organs (liver, muscle, heart) in vivo, as indicated by the increased lipidation of LC3B and the reduction of the abundance of the autophagic substrate sequestosome 1 (p62/SQSTM1). These changes were accompanied by the inhibition of the enzymatic activity of mammalian target of rapamycin complex 1 (mTORC1), leading to the reduced phosphorylation of p70(S6K), as well as by the global deacetylation of cellular proteins detectable by immunoblot. Immunohistochemical analyses of transgenic mice expressing a GFP-LC3B fusion protein confirmed the coffee-induced relocation of LC3B to autophagosomes, as well as general protein deacetylation. Altogether, these results indicate that coffee triggers 2 phenomena that are also induced by nutrient depletion, namely a reduction of protein acetylation coupled to an increase in autophagy. We speculate that polyphenols contained in coffee promote health by stimulating autophagy.

Prognostic value of LIPC in non-small cell lung carcinoma.

Non-small cell lung carcinoma (NSCLC) is the most common form of lung cancer and is associated with a high mortality rate worldwide. The majority of individuals bearing NSCLC are treated with surgery plus adjuvant cisplatin, an initially effective therapeutic regimen that, however, is unable to prevent relapse within 5 years after tumor resection in an elevated proportion of patients. The factors that predict the clinical course of NSCLC and its sensitivity to therapy remain largely obscure. One notable exception is provided by pyridoxal kinase (PDXK), the enzyme that generates the bioactive form of vitamin B6. PDXK has recently been shown to be required for optimal cisplatin responses in vitro and in vivo and to constitute a bona fide prognostic marker in the NSCLC setting. Together with PDXK, 84 additional factors were identified that influence the response of NSCLC cells to cisplatin, in vitro including the hepatic lipase LIPC. Here, we report that the intratumoral levels of LIPC, as assessed by immunohistochemistry in two independent cohorts of NSCLC patients, positively correlate with disease outcome. In one out of two cohorts studied, the overall survival of NSCLC patients bearing LIPChigh lesions was unaffected, if not slightly worsened, by cisplatin-based adjuvant therapy. Conversely, the overall survival of patients with LIPClow lesions was prolonged by post-operative cisplatin. Pending validation in appropriate clinical series, these results suggest that LIPClow NSCLC patients would be those who mainly benefit from adjuvant cisplatin therapy. Thus, the expression levels of LIPC appear to have an independent prognostic value (and perhaps a predictive potential) in the setting of NSCLC. If these findings were confirmed by additional studies, LIPC expression levels might allow not only for NSCLC patient stratification, but also for the implementation of personalized therapeutic approaches.

Analgesic, anti-inflammatory and anticancer activities of extra virgin olive oil.

Background. In folk medicine, extra virgin olive oil (EVOO) is used as a remedy for a variety of diseases. This study investigates the in vivo antinociceptive, anti-inflammatory, and anti-cancer effects of EVOO on mice and rats. Materials and Methods. In this experimental study, using the acetic acid-induced writhing and formalin tests in mice, the analgesic effect of EVOO was evaluated. Acetylsalicylic acid and morphine were used as standard drugs, respectively. The anti-inflammatory activity was investigated by means of the carrageenan-induced paw edema model in rats using acetylsalicylic acid and dexamethasone as standard drugs. Last, the xenograft model in athymic mice was used to evaluate the anticancer effect in vivo. Results. EVOO significantly decreased acetic acid-induced abdominal writhes and reduces acute and inflammatory pain in the two phases of the formalin test. It has also a better effect than Dexamethasone in the anti-inflammatory test. Finally, the intraperitoneal administration of EVOO affects the growth of HCT 116 tumours xenografted in athymic mice. Conclusion. EVOO has a significant analgesic, anti-inflammatory, and anticancer properties. However, further detailed studies are required to determine the active component responsible for these effects and mechanism pathway.

Multifunctional cells in human pituitary adenomas: implications for paradoxical secretion and tumorigenesis.

Pituitary adenomas are very common in humans. They are of monoclonal origin, very heterogeneous, and produce frequently paradoxical secretion. The normal anterior pituitary (AP) contains some unorthodox multifunctional cells able to store more than one AP hormone (polyhormonal) and/or to express multiple hypothalamic-releasing hormone receptors (multiresponsive). Multifunctional AP cells seem to be involved in plasticity processes such as transdifferentiation or paradoxical secretion. Here, we have characterized the single-cell phenotypes of 15 human pituitary tumors, including prolactinomas, nonfunctioning adenomas, and adenomas from multiple endocrine neoplasia type I (MEN-I) and pituitary Cushing's disease patients. Individual tumor cells were typed according to expression of AP hormones and hypothalamic-releasing hormone receptors by combination of calcium imaging and multiple sequential immunocytochemistry in the same cells. We found a large heterogeneity among the different tumors. In eight of the 15 tumors studied, more than 80% of the cells presented a multifunctional phenotype. This may explain the occurrence of paradoxical secretion. In addition, our results suggest that human pituitary adenomas might derive from multifunctional cells. This is consistent with the existence of a link between pituitary plasticity and tumorigenesis.