RICTOR/mTORC2 downregulation in BRAFV600E melanoma cells promotes resistance to BRAF/MEK inhibition.

BACKGROUND: The main drawback of BRAF/MEK inhibitors (BRAF/MEKi)-based targeted therapy in the management of BRAF-mutated cutaneous metastatic melanoma (MM) is the development of therapeutic resistance. We aimed to assess in this context the role of mTORC2, a signaling complex defined by the presence of the essential RICTOR subunit, regarded as an oncogenic driver in several tumor types, including MM. METHODS: After analyzing The Cancer Genome Atlas MM patients' database to explore both overall survival and molecular signatures as a function of intra-tumor RICTOR levels, we investigated the effects of RICTOR downregulation in BRAFV600E MM cell lines on their response to BRAF/MEKi. We performed proteomic screening to identify proteins modulated by changes in RICTOR expression, and Seahorse analysis to evaluate the effects of RICTOR depletion on mitochondrial respiration. The combination of BRAFi with drugs targeting proteins and processes emerged in the proteomic screening was carried out on RICTOR-deficient cells in vitro and in a xenograft setting in vivo. RESULTS: Low RICTOR levels in BRAF-mutated MM correlate with a worse clinical outcome. Gene Set Enrichment Analysis of low-RICTOR tumors display gene signatures suggestive of activation of the mitochondrial Electron Transport Chain (ETC) energy production. RICTOR-deficient BRAFV600E cells are intrinsically tolerant to BRAF/MEKi and anticipate the onset of resistance to BRAFi upon prolonged drug exposure. Moreover, in drug-naïve cells we observed a decline in RICTOR expression shortly after BRAFi exposure. In RICTOR-depleted cells, both mitochondrial respiration and expression of nicotinamide phosphoribosyltransferase (NAMPT) are enhanced, and their pharmacological inhibition restores sensitivity to BRAFi. CONCLUSIONS: Our work unveils an unforeseen tumor-suppressing role for mTORC2 in the early adaptation phase of BRAFV600E melanoma cells to targeted therapy and identifies the NAMPT-ETC axis as a potential therapeutic vulnerability of low RICTOR tumors. Importantly, our findings indicate that the evaluation of intra-tumor RICTOR levels has a prognostic value in metastatic melanoma and may help to guide therapeutic strategies in a personalized manner.

Carfilzomib, lenalidomide, dexamethasone (KRD) in BTKi relapsed or refractory mantle cell lymphoma: A phase II study from Fondazione Italiana Linfomi.

Mantle cell lymphoma (MCL) is a rare lymphoproliferative neoplasm considered incurable, with a median survival of 3-5 years. In recent years, Bruton's tyrosine kinase inhibitors (BTKi) have been introduced, demonstrating high therapeutic activity. However, the prognosis for MCL patients failing ibrutinib therapy is particularly poor, with a survival expectation of a few months. In this phase II trial, we assessed the efficacy and safety of the carfilzomib-lenalidomide-dexamethasone (KRD) combination in MCL patients who were relapsed/refractory (R/R) or intolerant to BTKi and in need of treatment. The primary objective of the study was to evaluate the antitumor efficacy of the KRD combination in terms of 12-month overall survival (12-month OS). From September 2019 to December 2020, 16 patients were enrolled from 11 Italian centers. After a median follow-up of 2.37 months (95% CI 0.92-6.47), the 12-month OS was 13%. The rate of grade 3-4 adverse events (AEs) was 35%, and the overall response rate (ORR) was 19%. These results led to the premature termination of enrollment, as defined in the protocol stopping rules. The efficacy of the KRD combination in advanced-stage MCL patients who are R/R to BTKi is unsatisfactory and too toxic.

IELSG38: phase II trial of front-line chlorambucil plus subcutaneous rituximab induction and maintenance in mucosa-associated lymphoid tissue lymphoma.

The IELSG38 trial was conducted to investigate the effects of subcutaneous (SC) rituximab on the complete remission (CR) rate and the benefits of SC maintenance in patients with extranodal marginal zone lymphoma (MZL) who received frontline treatment with chlorambucil plus rituximab. Study treatment comprised an induction phase with chlorambucil 6 mg/m2/day orally on weeks 1-6, 9-10, 13-14, 17-18, and 21-22, and rituximab 375 mg/m2 intravenously on day 1 of weeks 1-4, and 1400 mg SC on weeks 9, 13, 17, and 21. Then, a maintenance phase followed with rituximab administered at 1400 mg SC every two months for two years. Of the 112 patients enrolled, 109 were evaluated for efficacy. The CR rates increased from 52% at the end of the induction phase to 70% upon completion of the maintenance phase. With a median follow-up of 5.8 years, the 5-year event-free, progression-free, and overall survival rates were 87% (95% CI, 78-92), 84% (95% CI, 75-89), and 93% (95% CI, 86-96), respectively. The most common grade ≥3 toxicities were neutropenia (33%) and lymphocytopenia (16%). Six patients experienced treatment-related serious adverse events, including fever of unknown origin, sepsis, pneumonia, respiratory failure, severe cerebellar ataxia, and fatal acute myeloid leukemia. The trial showed that subcutaneous rituximab did not improve the complete remission rate at the conclusion of the induction phase, which was the main endpoint. Nevertheless, SC maintenance might have facilitated long-term disease control, potentially contributing to enhanced event-free and progression-free survival.

A chimeric human/dog-DNA vaccine against CSPG4 induces immunity with therapeutic potential in comparative preclinical models of osteosarcoma.

The high mortality rate of osteosarcoma (OSA) patients highlights the requirement of alternative strategies. The young age of patients, as well as the rarity and aggressiveness of the disease, limits opportunities for the robust testing of novel therapies, suggesting the need for valuable preclinical systems. Having previously shown the overexpression of the chondroitin sulfate proteoglycan (CSPG)4 in OSA, herein the functional consequences of its downmodulation in human OSA cells were evaluated in vitro, with a significant impairment of cell proliferation, migration, and osteosphere generation. The potential of a chimeric human/dog (HuDo)-CSPG4 DNA vaccine was explored in translational comparative OSA models, including human xenograft mouse models and canine patients affected by spontaneous OSA. The adoptive transfer of HuDo-CSPG4 vaccine-induced CD8+ T cells and sera in immunodeficient human OSA-bearing mice delayed tumor growth and metastasis development. HuDo-CSPG4 vaccination resulted safe and effective in inducing anti-CSPG4 immunity in OSA-affected dogs, which displayed prolonged survival as compared to controls. Finally, HuDo-CSPG4 was also able to induce a cytotoxic response in a human surrogate setting in vitro. On the basis of these results and the high predictive value of spontaneous OSA in dogs, this study paves the way for a possible translation of this approach to humans.

Breast cancer stem cell antigens as targets for immunotherapy.

The great success of immunotherapy is paving the way for a new era in cancer treatment and is driving major improvements in the therapy of patients suffering from a range of solid tumors. However, the choice of the appropriate tumor antigens to be targeted with cancer vaccines and T-cell therapies is still a challenge. Most antigens targeted so far have been identified on the tumor bulk and are expressed on differentiated cancer cells. The discovery of a small population of cancer stem cells (CSC), which is refractory to most current therapies and responsible for the development of metastasis and recurrence, has made it clear that the ideal targets for immunotherapies are the antigens that are expressed in CSC and play a key role in their function. Indeed, their immunotargeting would enable the eradication of CSC to be performed, thus eliminating the tumor source. We call these antigens "CSC oncoantigens". Herein, we summarize the controversial nature of breast CSC, discuss why they represent good candidates for cancer immunotherapy, and review the CSC antigens that have been used as targets for CSC immunotargeting this far. Moreover, we describe the pipeline that we have developed for the identification of fresh CSC oncoantigens, and present the pre-clinical results obtained with vaccines that target some of these antigens.

Biological features and outcome of diffuse large B-cell lymphoma associated with hepatitis C virus in elderly patients: Results of the prospective 'Elderly Project' by the Fondazione Italiana Linfomi.

Up to 10%-15% of diffuse large B-cell lymphoma (DLBCL) are related to hepatitis C virus (HCV) infection, in particular in elderly patients. The Fondazione Italiana Linfomi has recently published a multicentre prospective observational study, the 'Elderly Project', on the outcome of DLBCL in patients aged ≥65 years, evaluated using a simplified comprehensive geriatric assessment. The aim of this study was to compare biological and clinical features of HCV positive (HCV+) with HCV negative (HCV-) cases. A total of 89 HCV+ patients were identified out of 1095 evaluated for HCV serology (8.1%). The HCV+ patients were older, less fit, and had frequent extranodal involvement. The cell-of-origin determination by Nanostring showed that HCV+ cases less frequently had an activated B-cell profile compared to HCV- patients (18% vs. 43%). In all, 86% of HCV+ patients received rituximab-cyclophosphamide, doxorubicin, vincristine (Oncovin) and prednisone (R-CHOP)-like immunochemotherapy. Grade 3-4 liver toxicity occurred in 3% of cases. Among centrally reviewed cases confirmed as DLBCL, the 3-year overall survival of HCV+ patients was very similar to HCV- (63% vs. 61%, p = 0.926). In all, 20 HCV+ patients were treated with direct-acting antiviral agents (DAAs), with good tolerance and sustained virological response in all cases. The 3-year progression-free survival for this subgroup was excellent (77%), suggesting DAAs' possible role in reducing the risk of relapse by eliminating the viral trigger.

Diffuse large B-cell lymphoma in octogenarians aged 85 and older can benefit from treatment with curative intent: a report on 129 patients prospectively registered in the Elderly Project of the Fondazione Italiana Linfomi (FIL).

Octogenarian patients with diffuse large B-cell lymphoma are managed mainly with palliation, but recent improvement in their overall condition makes potentially curative treatment a possibility. Studies have shown that half of selected octogenarians may be cured using reduced-dose anthracycline chemoimmunotherapy. However, patients aged >85 (late octogenarians [LO]) were underrepresented, and selection criteria were poorly defined. We analyzed the clinical characteristics and outcomes of LO enrolled in the FIL Elderly Project in terms of the treatment received (palliative vs. curative) and of their simplified geriatric assessment (sGA), then compared them with early octogenarians (EO) aged 80- 84 and with those aged 65-79 classified as UNFIT or FRAIL according to sGA enrolled in the same study. Of the 1,163 patients, 370 were >80 and 129 LO. Clinical characteristics were similar between LO and EO, but LO more frequently received palliation (50% vs. 23%; P=0.001) and had worse 2-year overall survival (OS) (48% vs. 63%; P=0.001) and 2-year progression-free survival (PFS) (43% vs. 56%; P=0.01). Patients receiving anthracycline did better than patients receiving palliation (P<0.001), without any difference between full or reduced doses. Rituximab within palliation improved outcome (2-yr OS with or without rituximab 42% vs. 22%; P=0.008). Elderly Prognostic Index (EPI) performed better than sGA in identifying different risk categories, and high-risk EPI retained an independent unfavorable effect on OS and PFS, together with treatment without anthracycline. In conclusion, late octogenarians can benefit from a curative approach with reduced-dose anthracycline and from rituximab within palliation. EPI may help in patient selection more than sGA can.

The elderly prognostic index predicts early mortality in older patients with diffuse large B-cell lymphoma. An ad hoc analysis of the elderly project by the Fondazione Italiana Linfomi.

The Elderly Prognostic Index (EPI) is based on the integration of a simplified geriatric assessment, hemoglobin levels and International Prognostic Index and has been validated to predict overall survival in older patients with diffuse large B-cell lymphoma (DLBCL). In this study, we evaluated the ability of EPI to predict the risk of early mortality. This study included all patients registered in the Elderly Project for whom treatment details and a minimum follow-up of 3 months were available. Three main treatment groups were identified based on the anthracycline amount administered: cases receiving >70% of the theoretical anthracyclines dose (Full Dose [FD] group), ≤70% (Reduced Dose [RD]) and palliative therapy (PT; no anthracyclines). The primary endpoint was early mortality rate, defined as death for any cause occurring within 90 days from diagnosis. We identified 1150 patients with a median age of 76 years (range 65-94). Overall, 69 early deaths were observed, accounting for 19% of all reported deaths. The cumulative rate of early mortality at 90 days was 6.0%. Comparing early with delayed deaths, we observed a lower frequency of deaths due to lymphoma progression (42% vs. 75%; p < 0.001) and a higher frequency due to toxicity and infections (22% vs. 4%, p < 0.001, and 22% vs. 3%, p < 0.001, respectively) for early events. A multivariable logistic analysis on 931 patients (excluding PT) confirmed an independent association of high-risk EPI (odds ratio [OR] 3.60; 95% confidence interval [CI] 1.15-11.2) and bulky disease (OR 2.08; 95% CI 1.09-3.97) with the risk of early mortality. The cumulative incidence of early mortality for older patients with DLBCL is not negligible and is mainly associated with non-lymphoma related events. For patients receiving anthracyclines, high-risk EPI and bulky disease are associated with a higher probability of early mortality.

Efficacy of rituximab in anti-myelin-associated glycoprotein demyelinating polyneuropathy: Clinical, hematological and neurophysiological correlations during 2 years of follow-up.

BACKGROUND AND PURPOSE: We evaluated the clinical and neurophysiological efficacy of rituximab (RTX) in a neurophysiologically homogeneous group of patients with monoclonal gammopathy and immunoglobulin M (IgM) anti-myelin-associated glycoprotein antibody (anti-MAG) demyelinating polyneuropathy. METHODS: Twenty three anti-MAG-positive polyneuropathic patients were prospectively evaluated before and for 2 years after treatment with RTX 375 mg/m2 . The Inflammatory Neuropathy Cause and Treatment (INCAT) disability scale (INCAT-ds), modified INCAT sensory score (mISS), Medical Research Council sum score, Patients' Global Impression of Change scale were used, IgM levels were assessed and extensive electrophysiological examinations were performed before (T0) and 1 year (T1) and 2 years (T2) after RTX treatment. RESULTS: At T1 and T2 there was a significant reduction from T0 both in mISS and in INCAT-ds, with a p value < 0.001 in the inferential Friedman's test overall analysis. Ulnar nerve Terminal Latency Index and distal motor latency significantly changed from T0 to T1 and in the overall analysis (p = 0.001 and p = 0.002), and ulnar nerve sensory nerve action potential (SNAP) amplitude was significantly increased at T2 from T1, with a p value < 0.001 in the overall analysis. Analysis of the receiver-operating characteristic curves showed that a 41.8% increase in SNAP amplitude in the ulnar nerve at T2 from T0 was a fair predictor of a mISS reduction of ≥2 points (area under the curve 0.85; p = 0.005; sensitivity: 90.9%, specificity: 83.3%). CONCLUSIONS: This study suggests that RTX is effective in patients with clinically active demyelinating anti-MAG neuropathy over 2 years of follow-up, and that some neurophysiological variables might be useful for monitoring this efficacy.

Tumour acidosis evaluated in vivo by MRI-CEST pH imaging reveals breast cancer metastatic potential.

BACKGROUND: Tumour acidosis is considered to play a central role in promoting cancer invasion and migration, but few studies have investigated in vivo how tumour pH correlates with cancer invasion. This study aims to determine in vivo whether tumour acidity is associated with cancer metastatic potential. METHODS: Breast cancer cell lines with different metastatic potentials have been characterised for several markers of aggressiveness and invasiveness. Murine tumour models have been developed and assessed for lung metastases and tumour acidosis has been assessed in vivo by a magnetic resonance imaging-based chemical exchange saturation transfer (CEST) pH imaging approach. RESULTS: The higher metastatic potential of 4T1 and TS/A primary tumours, in comparison to the less aggressive TUBO and BALB-neuT ones, was confirmed by the highest expression of cancer cell stem markers (CD44+CD24-), highlighting their propensity to migrate and invade, coinciding with the measurement obtained by in vitro assays. MRI-CEST pH imaging successfully discriminated the more aggressive 4T1 and TS/A tumours that displayed a more acidic pH. Moreover, the observed higher tumour acidity was significantly correlated with an increased number of lung metastases. CONCLUSIONS: The findings of this study indicate that the extracellular acidification is associated with the metastatic potential.

Integration of cell of origin into the clinical CNS International Prognostic Index improves CNS relapse prediction in DLBCL.

Central nervous system (CNS) relapse carries a poor prognosis in diffuse large B-cell lymphoma (DLBCL). Integrating biomarkers into the CNS-International Prognostic Index (CNS-IPI) risk model may improve identification of patients at high risk for developing secondary CNS disease. CNS relapse was analyzed in 1418 DLBCL patients treated with obinutuzumab or rituximab plus cyclophosphamide, doxorubicin, vincristine, prednisone chemotherapy in the phase 3 GOYA study. Cell of origin (COO) was assessed using gene-expression profiling. BCL2 and MYC protein expression was analyzed by immunohistochemistry. The impact of CNS-IPI, COO, and BCL2/MYC dual-expression status on CNS relapse was assessed using a multivariate Cox regression model (data available in n = 1418, n = 933, and n = 688, respectively). High CNS-IPI score (hazard ratio [HR], 4.0; 95% confidence interval [CI], 1.3-12.3; P = .02) and activated B-cell‒like (ABC) (HR, 5.2; 95% CI, 2.1-12.9; P = .0004) or unclassified COO subtypes (HR, 4.2; 95% CI, 1.5-11.7; P = .006) were independently associated with CNS relapse. BCL2/MYC dual-expression status did not impact CNS relapse risk. Three risk subgroups were identified based on the presence of high CNS-IPI score and/or ABC/unclassified COO (CNS-IPI-C model): low risk (no risk factors, n = 450 [48.2%]), intermediate risk (1 factor, n = 408 [43.7%]), and high risk (both factors, n = 75 [8.0%]). Two-year CNS relapse rates were 0.5%, 4.4%, and 15.2% in the respective risk subgroups. Combining high CNS-IPI and ABC/unclassified COO improved CNS relapse prediction and identified a patient subgroup at high risk for developing CNS relapse. The study was registered at www.clinicaltrials.gov as #NCT01287741.

Early progression as a predictor of survival in marginal zone lymphomas: an analysis from the FIL-NF10 study.

Marginal zone lymphomas (MZLs) are indolent nonfollicular B-cell lymphomas (INFLs) and have heterogeneous clinical behavior. Recently, time to progression of disease at 24 months (POD24) was identified to stratify overall survival (OS) in follicular non-Hodgkin lymphoma and in INFL. Here, we examined the ability of POD24 to predict subsequent OS in a large, international cohort of MZL as part of the NF10 prospective international registry headed by Fondazione Italiana Linfomi (FIL). POD24 was only calculated for MZL patients requiring immediate therapy and was defined as experiencing lymphoma progression within 24 months from diagnosis. Among the 1325 patients enrolled in the NF10 study, we identified 321 patients with MZL for whom immediate therapy was planned right after lymphoma diagnosis. Overall, POD24 was confirmed in 59 patients (18%). Three-year OS for patients with POD24 was 53% with a hazard ratio of 19.5 (95% confidence interval, 8.4-45) compared with patients without POD24 (3-year OS, 95%). Association of POD24 with OS was confirmed for the subgroup of splenic and extranodal MZLs. Assessment of POD24 stratifies subsequent outcome in MZL and identifies a high-risk population. This trial was registered at www.clinicaltrials.gov as #NCT02904577.

Targeted locus amplification to detect molecular markers in mantle cell and follicular lymphoma.

Minimal residual disease (MRD) monitoring by PCR methods is a strong and standardized predictor of clinical outcome in mantle cell lymphoma (MCL) and follicular lymphoma (FL). However, about 20% of MCL and 40% of FL patients lack a reliable molecular marker, being thus not eligible for MRD studies. Recently, targeted locus amplification (TLA), a next-generation sequencing (NGS) method based on the physical proximity of DNA sequences for target selection, identified novel gene rearrangements in leukemia. The aim of this study was to test TLA in MCL and FL diagnostic samples lacking a classical, PCR-detectable, t(11; 14) MTC (BCL1/IGH), or t(14; 18) major breakpoint region and minor cluster region (BCL2/IGH) rearrangements. Overall, TLA was performed on 20 MCL bone marrow (BM) or peripheral blood (PB) primary samples and on 20 FL BM, identifying a novel BCL1 or BCL2/IGH breakpoint in 16 MCL and 8 FL patients (80% and 40%, respectively). These new breakpoints (named BCL1-TLA and BCL2-TLA) were validated by ASO primers design and compared as MRD markers to classical IGH rearrangements in eight MCL: overall, MRD results by BCL1-TLA were superimposable (R Pearson = 0.76) to the standardized IGH-based approach. Moreover, MRD by BCL2-TLA reached good sensitivity levels also in FL and was predictive of a primary refractory case. In conclusion, this study offers the proof of principle that TLA is a promising and reliable NGS-based technology for the identification of novel molecular markers, suitable for further MRD analysis in previously not traceable MCL and FL patients.

Health-related quality of life and utility outcomes with selinexor in relapsed/refractory diffuse large B-cell lymphoma.

Aim: Evaluate health-related quality of life (HRQoL) and health utility impact of single-agent selinexor in heavily pretreated patients with relapsed/refractory diffuse large B-cell lymphoma. Patients & methods: Functional Assessment of Cancer Therapy (FACT) - Lymphoma and EuroQoL five-dimensions five-levels data collected in the single-arm Phase IIb trial SADAL (NCT02227251) were analyzed with mixed-effects models. Results: Treatment responders maintained higher FACT - Lymphoma (p ≤ 0.05), FACT - General (p < 0.05) and EuroQoL five-dimensions five-levels index scores (p < 0.001) beginning in cycle 3. The estimated difference in health state utilities for treatment response and progressive disease was both statistically significant and clinically meaningful (mean difference: 0.07; p = 0.001). Conclusion: In patients with relapsed/refractory diffuse large B-cell lymphoma, objective response to selinexor was associated with HRQoL maintenance, reduction in disease-related HRQoL decrements and higher health utilities.

Lay abstract This work examined quality of life (QoL) among patients with relapsed/refractory diffuse large B-cell lymphoma with two to five prior therapies who received single-agent selinexor in the SADAL clinical trial. Analysis of patient-reported Functional Assessment of Cancer Therapy ­ Lymphoma and EuroQoL five-dimensions five-levels data showed that patients who had objective clinical response to selinexor maintained their QoL over the course of treatment. Grade ≥3 adverse events and serious adverse events were not associated with clinically meaningful negative QoL impacts. Clinical trial registration: NCT02227251 (ClinicalTrials.gov).

ABVD vs BEACOPP escalated in advanced-stage Hodgkin's lymphoma: Results from a multicenter European study.

The optimal first-line treatment for advanced-stage Hodgkin's lymphoma (HL) is still a matter of debate. While ABVD is less toxic and as effective as other, more intensive chemotherapy regimens, escalated BEACOPP (BEACOPPesc) is superior to ABVD for initial disease control and prolonged time-to-relapse. However, this advantage is associated with higher rate of early and late toxicities. As most of these data have been accumulated from clinical trials, a retrospective analysis was conducted in a large database of patients treated outside clinical trials to investigate the advantages and disadvantages of these regimes in a real-world setting. From October 2009 to October 2018, 397 advanced-stage HL patients treated with either ABVD or BEACOPPesc were retrospectively assessed in 7 European cancer centers (2 Austrian and 5 Italian centers). Complete metabolic remission (CMR) by PET was achieved in 76% and 85% of patients in the ABVD and BEACOPPesc groups, respectively (p = .01). Severe adverse events occurred more frequently with BEACOPPesc than ABVD. At a median follow-up of 8 years, 9% of the patients who achieved CMR after BEACOPPesc relapsed compared to 16.6% in the ABVD group (p = .043). No statistical difference in progression free survival (PFS) was observed between the two cohorts overall (p = .11), but there was a trend towards a superior PFS in high-risk patients treated with BEACOPPesc (p = .074). Nevertheless, overall survival was similar between the two groups (p = .94). In conclusion, we confirm that ABVD is an effective and less toxic therapeutic option for advanced-stage HL. Although BEACOPP results in better initial tumor control, the long-term outcome remains similar between the two regimens.

Toll-Like Receptor 2 at the Crossroad between Cancer Cells, the Immune System, and the Microbiota.

Toll-like receptor 2 (TLR2) expressed on myeloid cells mediates the recognition of harmful molecules belonging to invading pathogens or host damaged tissues, leading to inflammation. For this ability to activate immune responses, TLR2 has been considered a player in anti-cancer immunity. Therefore, TLR2 agonists have been used as adjuvants for anti-cancer immunotherapies. However, TLR2 is also expressed on neoplastic cells from different malignancies and promotes their proliferation through activation of the myeloid differentiation primary response protein 88 (MyD88)/nuclear factor kappa-light-chain-enhancer of activated B cell (NF-κB) pathway. Furthermore, its activation on regulatory immune cells may contribute to the generation of an immunosuppressive microenvironment and of the pre-metastatic niche, promoting cancer progression. Thus, TLR2 represents a double-edge sword, whose role in cancer needs to be carefully understood for the setup of effective therapies. In this review, we discuss the divergent effects induced by TLR2 activation in different immune cell populations, cancer cells, and cancer stem cells. Moreover, we analyze the stimuli that lead to its activation in the tumor microenvironment, addressing the role of danger, pathogen, and microbiota-associated molecular patterns and their modulation during cancer treatments. This information will contribute to the scientific debate on the use of TLR2 agonists or antagonists in cancer treatment and pave the way for new therapeutic avenues.

Non-Melanoma Skin Cancers: Biological and Clinical Features.

Non-melanoma skin cancers (NMSCs) include basal cell carcinoma (BCC), squamous cell carcinoma (SCC) and Merkel cell carcinoma (MCC). These neoplasms are highly diverse in their clinical presentation, as well as in their biological evolution. While the deregulation of the Hedgehog pathway is commonly observed in BCC, SCC and MCC are characterized by a strikingly elevated mutational and neoantigen burden. As result of our improved understanding of the biology of non-melanoma skin cancers, innovative treatment options including inhibitors of the Hedgehog pathway and immunotherapeutic agents have been recently investigated against these malignancies, leading to their approval by regulatory authorities. Herein, we review the most relevant biological and clinical features of NMSC, focusing on innovative treatment approaches.

Outcome of transformed follicular lymphoma worsens according to the timing of transformation and to the number of previous therapies. A retrospective multicenter study on behalf of Fondazione Italiana Linfomi (FIL).

Optimal treatment for transformed follicular lymphoma (tFL) is not fully defined. Clinical characteristics and treatments that impact on post-transformation outcome of 176 biopsy-proven tFL were analysed. Transformation occurred at initial diagnosis in 52% (Group 1) and after a FL diagnosis in 48% (Group 2). Five-year overall survival was 84% for Group 1 and 51% for Group 2 (P < 0·001). In Group 1, 5-year progression-free survival was superior after rituximab maintenance compared to observation only (94% vs. 53%, P = 0·024). In Group 2, an inverse trend was found between survival and both a higher number of pre-transformation treatment lines and a short time-to-transformation.

Naturally occurring cancers in pet dogs as pre-clinical models for cancer immunotherapy.

Despite the significant progress in tumor prevention, early detection, diagnosis and treatment made over recent decades, cancer is still an enormous public health challenge all around the world, with the number of people affected increasing every year. A great deal of effort is therefore being devoted to the search for novel safe, effective and economically sustainable treatments for the growing population of neoplastic patients. One main obstacle to this process is the extremely low percentage of therapeutic approaches that, after successfully passing pre-clinical testing, actually demonstrate activity when finally tested in humans. This disappointing and expensive failure rate is partly due to the pre-clinical murine models used for in vivo testing, which cannot faithfully recapitulate the multifaceted nature and evolution of human malignancies. These features are better mirrored in natural disease models, i.e., companion animals affected by cancers. Herein, we discuss the relevance of spontaneous canine tumors for the evaluation of the safety and anti-tumor activity of novel therapeutic strategies before in-human trials, and present our experience in the development of a vaccine that targets chondroitin sulphate proteoglycan (CSPG)4 as an example of these comparative oncology studies.

Fighting breast cancer stem cells through the immune-targeting of the xCT cystine-glutamate antiporter.

Tumor relapse and metastatic spreading act as major hindrances to achieve complete cure of breast cancer. Evidence suggests that cancer stem cells (CSC) would function as a reservoir for the local and distant recurrence of the disease, due to their resistance to radio- and chemotherapy and their ability to regenerate the tumor. Therefore, the identification of appropriate molecular targets expressed by CSC may be critical in the development of more effective therapies. Our studies focused on the identification of mammary CSC antigens and on the development of CSC-targeting vaccines. We compared the transcriptional profile of CSC-enriched tumorspheres from an Her2+ breast cancer cell line with that of the more differentiated parental cells. Among the molecules strongly upregulated in tumorspheres we selected the transmembrane amino-acid antiporter xCT. In this review, we summarize the results we obtained with different xCT-targeting vaccines. We show that, despite xCT being a self-antigen, vaccination was able to induce a humoral immune response that delayed primary tumor growth and strongly impaired pulmonary metastasis formation in mice challenged with tumorsphere-derived cells. Moreover, immunotargeting of xCT was able to increase CSC chemosensitivity to doxorubicin, suggesting that it may act as an adjuvant to chemotherapy. In conclusion, our approach based on the comparison of the transcriptome of tumorspheres and parental cells allowed us to identify a novel CSC-related target and to develop preclinical therapeutic approaches able to impact on CSC biology, and therefore, hampering tumor growth and dissemination.