Macrophage-derived CXCL9 and CXCL11, T-cell skin homing, and disease control in mogamulizumab-treated CTCL patients.

Cutaneous T-cell lymphomas (CTCLs) are rare malignancies involving primarily the skin. Responses to treatment are usually short-lived in advanced CTCL. The determinants of long-term CTCL control are unclear. Mogamulizumab, an anti-human CCR4 antibody that acts by antibody-dependent cell cytotoxicity against CCR4+ CTCL tumor cells and peripheral memory blood regulatory T cells, has been associated with long-lasting remissions and immune adverse events. Here, we reported skin rashes in 32% of 44 patients with CTCL treated with mogamulizumab, associated with significantly higher overall survival (hazard ratio, 0.16; 0.04-0.73; P = .01). Rash occurred in patients with Sézary syndrome and was associated with longer time to progression. These rashes were characterized by a CD163+ granulomatous and/or CD8+ lichenoid skin infiltrate. High-throughput sequencing analysis of T-cell receptor ß genes in skin and blood flow cytometry confirmed the depletion of CTCL tumor cells, as well as the recruitment of new reactive T-cell clones in skin at the time of skin rash. CXCL9 and CXCL11, two macrophage-derived chemokines that recruit CXCR3+ T cells to skin, were overexpressed in skin rashes. A higher frequency of TIGIT+ and PD1+ exhausted reactive blood T cells was observed at baseline in patients with rash, and this frequency decreased with mogamulizumab treatment. These data are consistent with mogamulizumab-induced long-term immune CTCL control by activation of the macrophage and T-cell responses in patients with rash.

Porocarcinomas with PAK1/2/3 fusions: a series of 12 cases.

AIMS: Porocarcinoma is a malignant sweat gland tumour differentiated toward the upper part of the sweat duct and may arise from the transformation of a preexisting benign poroma. In 2019, Sekine et al. demonstrated the presence of YAP1::MAML2 and YAP1::NUTM1 fusions in most poromas and porocarcinomas. Recently, our group identified PAK2-fusions in a subset of benign poromas. Herein we report a series of 12 porocarcinoma cases harbouring PAK1/2/3 fusions. METHODS AND RESULTS: Five patients were male and the median age was 79 years (ranges: 59-95). Tumours were located on the trunk (n = 7), on the thigh (n = 3), neck (n = 1), or groin area (n = 1). Four patients developed distant metastases. Microscopically, seven cases harboured a benign poroma component and a malignant invasive part. Ductal formations were observed in all, while infundibular/horn cysts and cells with vacuolated cytoplasm were detected in seven and six tumours, respectively. In three cases, the invasive component consisted of a proliferation of elongated cells, some of which formed pseudovascular spaces, whereas the others harboured a predominant solid or trabecular growth pattern. Immunohistochemical staining for CEA and EMA confirmed the presence of ducts. Focal androgen receptor expression was detected in three specimens. Whole RNA sequencing evidenced LAMTOR1::PAK1 (n = 2), ZDHHC5::PAK1 (n = 2), DLG1::PAK2, CTDSP1::PAK1, CTNND1::PAK1, SSR1::PAK3, CTNNA1::PAK2, RNF13::PAK2, ROBO1::PAK2, and CD47::PAK2. Activating mutation of HRAS (G13V, n = 3, G13R, n = 1, Q61L, n = 2) was present in six cases. CONCLUSION: Our study suggests that PAK1/2/3 fusions is the oncogenic driver of a subset of porocarcinomas lacking YAP1 rearrangement.

Microsecretory adenocarcinoma of the skin, a novel type of sweat gland carcinoma: Report of three additional cases.

Microsecretory adenocarcinoma (MSA) is a newly described salivary gland tumor harboring a characteristic balanced chromosomal translocation resulting in MEF2C::SS18 gene fusion. Six primary cutaneous MSA cases have been recently described. We report three additional cases confirming the relevance of this recently identified entity of primary cutaneous adnexal tumor. Three patients aged 53-, 64- and 78-year-old were retrospectively diagnosed with MSA of the skin (MSAS) as consultation cases of the CARADERM (CAncers RAres DERMatologiques) national network. The clinical presentation was an indolent nodule on the upper extremities. There was no history of salivary gland tumor. Histopathologically, the tumors presented as dermal nodular proliferation with slightly infiltrative borders, composed of cribriform and microcystic structures with abundant myxoid intraluminal secretion embedded in a fibromyxoid stroma. They diffusely expressed cytokeratin 8 and SOX10, focally p63 and heterogeneously smooth muscle actin. All tumors harbored the MEF2C::SS18 gene fusion. A complete surgical excision was performed. No local recurrence or distant metastases were observed so far (follow-up: 17, 38, and 45 months). MSAS is the cutaneous homologue of MSA of the salivary gland, a low-grade adnexal neoplasm whose prognosis seems to be excellent once the complete removal of the tumor is assured.

Mechanisms of resistance and predictive biomarkers of response to targeted therapies and immunotherapies in metastatic melanoma.

PURPOSE OF REVIEW: Thanks to mitogen-activated protein kinase inhibitors (MAPKi) and immune checkpoint inhibitors (ICI), major progress has been made in the field of melanoma treatment. However, long-term success is still scarce because of the development of resistance. Understanding these mechanisms of resistance and identifying predictive genomic biomarkers are now key points in the therapeutic management of melanoma patients. RECENT FINDINGS: Multiple and complex mechanisms of resistance to MAPKi or ICI have been uncovered in the past few years. The lack of response can be driven by mutations and nonmutational events in tumor cells, as well as by changes in the tumor microenvironment. Melanoma cells are also capable of rapidly switching their molecular and cellular phenotype, leading to an initial drug-tolerant favorizing melanoma resistance. Tumor molecular profiling and circulating tumor cell analyses are of high interest as predictive biomarkers as well as studying immunogenic changes and microbiome in ICI-treated patients. SUMMARY: Resistance to MAPKi and ICI is a key point in therapeutic management of metastatic melanoma patients. Validated biomarkers predicting response to therapy are urgently needed to move toward personalized medicine. Combinatory treatments guided by the understanding of resistance mechanisms will be of major importance in the future of melanoma therapy.

Trough Levels of Infliximab at Week 6 Are Predictive of Remission at Week 14 in Pediatric Crohn's Disease.

OBJECTIVE: Infliximab (IFX) is a frequent therapeutic option for Crohn disease (CD) patients. Early detection of responders to IFX is critical for the management of CD in order to avoid long-term exposure to the drug without benefit. This retrospective study aimed at analysing which early parameters recorded during the induction period are able to predict response to IFX during the maintenance period in pediatric CD. PATIENTS AND METHODS: Medical records of all CD patients ages from 2 to 18 years who received IFX at a tertiary IBD center were retrospectively analyzed. Children were classified in 3 groups according to their response at week 14 (W14) remission, clinical response or , no response. The factors recorded at W0, W2, and W6, which were associated with remission at W14 were analyzed using a logistic regression. RESULTS: Among the 111 patients included, 74.8% patients were responders to IFX at W14, including 38.7% in clinical remission and 36% with partial clinical response. Clinical remission at W14 was associated with normal growth (P < 0.01), and normal albuminemia (P = 0.01) at baseline, It was also associated with trough levels to IFX >8.3 µg/ml at week 6 (P < 0.01). CONCLUSION: Trough levels to IFX >8.3 µg/ml at week 6 are predictive of remission at W14 for luminal disease.

Infliximab Paradoxical Psoriasis in a Cohort of Children With Inflammatory Bowel Disease.

OBJECTIVES: In adult inflammatory bowel disease (IBD) treated by anti-TNF antibodies, paradoxical psoriasis has an estimated prevalence of 1.6 to 22%, especially in infliximab (IFX)-treated patients. Little is known in the pediatric IBD (PIBD) populations. METHODS: All patients ages from 2 to 18 years with Crohn disease (CD) or ulcerative colitis (UC) and treated for the first time by IFX between January 2002 and March 2014, were considered for inclusion in this retrospective study performed in a tertiary PIBD centre. Paradoxical psoriasis events together with clinical and biological data were collected in all patients. Comparisons between psoriasis and control groups were performed using univariate statistical analyses. RESULTS: One hundred and twenty-three CD patients and 24 UC patients were treated with IFX. Twenty patients (13.6%) experienced a paradoxical psoriasis. All of them were affected by CD. Perianal CD was more frequent in the psoriasis group (P = 0.033). Fourteen patients (70%) were in remission when skin lesions occurred. Paradoxical psoriasis was diagnosed 355 days (median, interquartile range [IQR] 239; 532) after the initiation of IFX corresponding to the eighth injection (median, IQR: 6; 15). Psoriasis lesions were controlled by local steroids in all cases and no patients discontinued IFX therapy. CONCLUSIONS: 13.6% of our IBD patients treated with IFX developed psoriasis during a median follow-up of 23.9 months (IQR: 11.6; 36.5). Crohn disease patients with perianal disease were at a higher risk to develop this common side effect.

Effect of cumulative exposure to corticosteroid and DMARD on radiographic progression in rheumatoid arthritis: results from the ESPOIR cohort.

Objectives: Several authors have tried to predict the risk of radiographic progression in RA according to baseline characteristics, considering exposure to treatment only as a binary variable (Treated: Yes/No). This study aims to model the risk of 5-year radiographic progression taking into account both baseline characteristics and the cumulative time-varying exposure to corticosteroids or DMARDs. Methods: The study population consisted of 403 patients of the Etude et Suivi des Polyarthrites Indifférenciées Récentes cohort meeting the 1987 ACR or 2010 ACR/EULAR criteria for RA at inclusion and having complete radiographic data at baseline and 5 years. Radiographic progression was defined at 5 years as a significant increase of the Sharp/van der Heidje score (smallest detectable difference ⩾5). The best logistic regression model was selected from the following: model including only clinico-biological baseline characteristics; model considering baseline characteristics and treatments as binary variables; and model considering baseline characteristics and treatments as weighted cumulative exposure variables. Results: Radiographic progression occurred in 143 (35.5%) patients. The best model combined anti-citrullinated peptide antibody positivity, ESR, swollen joint count >14 and erosion score at baseline, as well as corticosteroids, MTX/LEF (MTX or LEF) and biologic DMARDs (bDMARDs) as weighted cumulative exposure variables. Recent cumulative exposure to high doses of corticosteroids (⩽ 3months) was significantly associated with the risk of 5-year radiographic progression and a significant protective association was highlighted for a 36-month exposure to bDMARDs. Conclusion: Corticosteroids and bDMARDs play an important role in radiographic progression. Accounting for treatment class and intensity of exposure is a major concern in predictive models of radiographic progression in RA patients.

Inactivation of kindlin-3 increases human melanoma aggressiveness through the collagen-activated tyrosine kinase receptor DDR1.

The role of the focal adhesion protein kindlin-3 as a tumor suppressor and its interaction mechanisms with extracellular matrix constitute a major field of investigation to better decipher tumor progression. Besides the well-described role of kindlin-3 in integrin activation, evidence regarding modulatory functions between melanoma cells and tumor microenvironment are lacking and data are needed to understand mechanisms driven by kindlin-3 inactivation. Here, we show that kindlin-3 inactivation through knockdown or somatic mutations increases BRAFV600mut melanoma cells oncogenic properties via collagen-related signaling by decreasing cell adhesion and enhancing proliferation and migration in vitro, and by promoting tumor growth in mice. Mechanistic analysis reveals that kindlin-3 interacts with the collagen-activated tyrosine kinase receptor DDR1 (Discoidin domain receptor 1) modulating its expression and its interaction with ß1-integrin. Kindlin-3 knockdown or mutational inactivation disrupt DDR1/ß1-integrin complex in vitro and in vivo and its loss improves the anti-proliferative effect of DDR1 inhibition. In agreement, kindlin-3 downregulation is associated with DDR1 over-expression in situ and linked to worse melanoma prognosis. Our study reveals a unique mechanism of action of kindlin-3 in the regulation of tumorigenesis mediated by the collagen-activated tyrosine kinase receptor DDR1 thus paving the way for innovative therapeutic targeting approaches in melanoma.

Combined PDE4+MEK inhibition shows antiproliferative effects in NRASQ61 mutated melanoma preclinical models.

Upregulation of phosphodiesterase type 4 (PDE4) has been associated with worse prognosis in several cancers. In melanomas harboring NRAS mutations, PDE4 upregulation has been shown to trigger a switch in signaling from BRAF to RAF1 which leads to mitogen-activated protein kinase pathway activation. Previous in vitro evidence showed that PDE4 inhibition induced death in NRASQ61mut melanoma cells and such a strategy may thus be a relevant therapeutic option in those cases with no molecular targeted therapies approved to date. In this study, we generated patient-derived xenografts (PDX) from two NRASQ61mut melanoma lesions. We performed ex vivo histoculture drug response assays and in vivo experiments. A significant ex vivo inhibition of proliferation with the combination of roflumilast+cobimetinib was observed compared to dimethyl sulfoxide control in both models (51 and 67%). This antiproliferative effect was confirmed in vivo for PDX-1 with a 56% inhibition of tumor growth. To decipher molecular mechanisms underlying this effect, we performed transcriptomic analyses and revealed a decrease in MKI67, RAF1 and CCND1 expression under bitherapy. Our findings strengthen the therapeutic interest of PDE4 inhibitors and support further experiments to evaluate this approach in metastatic melanoma.

TERT Expression Induces Resistance to BRAF and MEK Inhibitors in BRAF-Mutated Melanoma In Vitro.

Because BRAF-mutated melanomas are addicted to the Mitogen Activated Protein Kinase (MAPK) pathway they show a high response rate to BRAF and MEK inhibitors. However, the clinical responses to these inhibitors are often short-lived with the rapid onset of resistance to treatment. Deciphering the molecular mechanisms driving resistance has been the subject of intense research. Recent in vitro and clinical data have suggested a link between expression of telomerase and resistance to targeted therapy in melanoma. TERT promoter mutations are the main mechanism for the continuous upregulation of telomerase in melanoma and co-occur frequently with BRAF alterations. To understand how TERT promoter mutations could be associated with resistance to targeted therapy in melanoma, we conducted translational and in vitro studies. In a cohort of V600E-BRAF-mutated melanoma patients, we showed that the TERT promoter mutation status and TERT expression tended to be associated with response to BRAF and MEK inhibitors. We demonstrated that TERT overexpression in BRAF-mutated melanoma cells reduced sensitivity to BRAF and MEK independently of TERT's telomer maintenance activity. Interestingly, inhibition of TERT reduced growth of BRAF-mutated melanoma including resistant cells. TERT expression in melanoma can therefore be a new biomarker for resistance to MAPK inhibitors as well as a novel therapeutic target.

Pharmacogenomics in solid cancers and hematologic malignancies: Improving personalized drug prescription.

The discovery of molecular alterations involved in oncogenesis is evolving rapidly and has led to the development of new innovative targeted therapies in oncology. High-throughput sequencing techniques help to identify genomic targets and to provide predictive molecular biomarkers of response to guide alternative therapeutic strategies. Besides the emergence of these theranostic markers for the new targeted treatments, pharmacogenetic markers (corresponding to genetic variants existing in the constitutional DNA, i.e., the host genome) can help to optimize the use of chemotherapy. In this review, we present the current clinical applications of constitutional PG and the recent concepts and advances in pharmacogenomics, a rapidly evolving field that focuses on various molecular alterations identified on constitutional or somatic (tumor) genome.

Clinicopathologic and molecular characterization of melanomas mutated for CTNNB1 and MAPK.

Wnt/ß-catenin signaling plays crucial roles in melanocyte biology and may be implicated in melanoma progression. In this study, we retrospectively examined a real-life cohort of melanomas mutated for ß-catenin (CTNNB1), in association or not with a MAPK mutation (of BRAF or NRAS), and analyzed their clinical, histopathological, and molecular characteristics. Our results indicate that, regardless of the presence of a concurrent MAPK mutation, CTNNB1mut cutaneous primary melanomas display more proliferative hallmarks (increased Breslow thickness, mitotic index, and ulceration) than their CTNNB1 wild-type counterparts. Accordingly, they often progress to the metastatic stage. Furthermore, concurrent CTNNB1 and MAPK mutations do not necessarily confer a deep penetrating nevi phenotype. Altogether, this study provides evidence that CTNNB1 mutations in melanomas are associated with specific clinical and pathological features.

Custom pyrosequencing assay to detect short BRAF deletions in Langerhans cell histiocytic lesions.

Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplastic disease driven by activating mutations in the mitogen-activating protein kinase signalling pathway, including the BRAF V600E mutation and BRAF deletions (BRAFdel). Next-generation sequencing and whole exome sequencing (WES) are valuable and powerful approaches for BRAFdel identification, but these techniques are costly and time consuming. Pyrosequencing is an alternative method that has the potential to rapidly and reliably identify gene deletions. We developed a custom pyrosequencing assay to detect the exon-12 BRAFdel in 18 biopsies from adult patients with LCH, which were all genotyped in parallel using Sanger sequencing and WES. A BRAFdel was detected in 7/18 (39%), 6/18 (33%) and 3/18 (17%) LCH lesions using WES, pyrosequencing and Sanger, respectively, with good concordance between the WES and pyrosequencing results (Kappa-coefficient=0.88). Therefore, our pyrosequencing assay is reliable and useful for detecting BRAFdel, particularly in BRAF V600E-negative LCH lesions, for which targeted treatment is indicated.