Uncovering immune checkpoint heterogeneity in oral squamous cell carcinoma using single cell RNA-sequencing data highlights three subgroups of patients with distinct immune phenotypes.

OBJECTIVES: In head and neck squamous cell carcinoma (HNSCC), PD-1/PD-L1 inhibitors remain inefficient in most patients, which points to the need for better characterization of immune checkpoint (ICP) molecule expression. MATERIAL AND METHODS: We evaluated the expression of 22 ICP ligands (ICPL) in 2,176 malignant cells from 10 patients in a public single-cell RNA-sequencing dataset and in two cohorts of HNSCC patients for which gene expression data are available. RESULTS: Based on ICPL expression, malignant cells formed three distinct clusters characterized either by a strong expression of ICPL together with an immune phenotype linked to IFN-γ response (cluster 1) or by a weak ICPL expression and little response to IFN-γ (clusters 2 and 3). Malignant cells from cluster 3 showed a high PD-L1 expression associated with NRF2 signature. The relevance of 3 groups of patients, i.e "high ICPL/high IFN-γ", "low ICPL/low IFN-γ" or "low ICPL/low IFN-γ/high PD-L1" was confirmed in a cohort of 259 OSCC whole tumor samples from TCGA and in the CLB-IHN cohort including patients treated with PD1/PD-L1 inhibitors. The heterogeneous expression of ICPL among patients' malignant cells was associated with immunologically distinct microenvironments, evaluated with the "hot/cold" and the Tumor microenvironment (TME) classification. Finally, the "low ICPL/low IFN-γ/high PD-L1" group 3 displayed a poor prognosis in the TCGA cohort. CONCLUSION: Hence, the global picture of ICPL gene expression in malignant cells from HNSCC patients may contribute to the broader issue of improving immunotherapy strategies though a better stratification of patients and the design of new treatment combinations.

[Uterin adenosarcoma: French Guidelines of the French Sarcoma Group and the Rare Gynecologic Tumor Group]. / Adénosarcomes mullériens de l'utérus ­ référentiels de prise en charge du GSF-GETO/NETSARC+ et du groupe TMRG.

Uterine adenosarcoma is a very rare malignancy defined as a biphasic tumor composed of both benign epithelial component and a malignant sarcoma component. The stage of the disease is determined by the presence of myometrial invasion and the extent of extra-uterine disease. The most important histopronostic factors are the existence of a sarcomatous overgrowth defined by a sarcomatous contingent occupying more than 25 % of the volume of the tumor (directly correlated to the grade of the disease), the presence of a heterologous and/or a high-grade component. Stage I adenosarcomas without sarcomatous overgrowth have a good prognosis, with an overall 5-year survival of up to 80 %. In localized disease, complete surgical removal is recommended. The role of hormone therapy, chemotherapy and adjuvant radiotherapy is not established. If possible, relapses should be re-treated surgically, with the aim of achieving complete resection. In the advanced inoperable or metastatic setting, hormone therapy is an option for low-grade adenosarcomas with estrogen receptor (ER) and progesterone receptor (PR) overexpression. For high-grade tumors, the standard chemotherapies are doxorubicin-based combinations, although an integrated approach of surgery and medical treatment should also be considered in this setting.

Datasets for gene expression profiles of head and neck squamous cell carcinoma and lung cancer treated or not by PD1/PD-L1 inhibitors.

Identification of tumors harboring an overall active immune phenotype may help for selecting patients with advanced head and neck squamous cell carcinomas (HNSCC) and non-small cell lung cancer (NSCLC) who may benefit from immunotherapies. In this context, we generated targeted gene expression profiles in three and two independent cohorts of patients with HNSCC or NSCLC respectively, treated or not by PD-1/PD-L1 inhibitors. Notably, we generated two datasets including 102 and 82 patients with HNSCC or NSCLC treated with PD-1/PD-L1 inhibitors. Clinical information, including detailed survival raw data, is available for each patient, allowing to test association between gene expression data and patient survival (overall and progression-free survival). Moreover, we also generated gene expression datasets of 27 paired HNSCC samples from diagnostic biopsies and versus surgically resected specimens as well as 33 paired HNSCC samples at initial diagnosis (untreated) and at recurrence. Those datasets may allow to test the stability of a given biomarker across paired samples.

Immunologically active phenotype by gene expression profiling is associated with clinical benefit from PD-1/PD-L1 inhibitors in real-world head and neck and lung cancer patients.

INTRODUCTION: Identification of tumours harbouring an overall active immune phenotype may help for selecting patients with advanced head and neck squamous cell carcinomas (HNSCC) and non-small cell lung cancer (NSCLC) who may benefit from immunotherapies. Our objective was to develop a reliable and stable scoring system to identify those immunologically active tumours. METHODS: Using gene expression profiles of 421 HNSCC, we developed a score to identify immunologically active tumours. Validation of the 'HOT' score was done in 40 HNSCC and 992 NSCLC. Stability of the 'HOT' score was tested in paired HNSCC samples from diagnostic biopsies versus surgically resected specimens, untreated versus recurrent samples, and pre-versus post-cetuximab samples in a total of 76 patients. The association between the 'HOT' score with overall survival (OS) and progression-free survival (PFS) was tested in 184 patients with HNSCC or NSCLC treated with PD-1/PD-L1 inhibitors. RESULTS: A 27-gene expression based 'HOT' score was correlated with: (i) PD-L1 and IDO1 expression, (ii) TCD8 infiltrate and (iii) activation of the IFN-γ pathway. The HOT score concordance when comparing diagnostic biopsies and surgically resected specimens was higher than in untreated samples versus recurrent or pre-versus post-cetuximab samples. In 102 and 82 patients with HNSCC or NSCLC treated with PD-1/PD-L1 inhibitors, the HOT score was associated with an improved OS and PFS in multivariate analysis. CONCLUSION: The 'HOT' score is a simple and robust approach to identify real-world patients with HNSCC and NSCLC immunologically active tumours who may benefit from PD-1/PD-L1 inhibitors.

Molecular Mechanisms of Kaposi Sarcoma Development.

Kaposi's sarcoma (KS) is a heterogeneous angioproliferative tumor that generally arises in the skin. At least four forms of this disease have been described, with the 'HIV'-related form being the most aggressive and can involve mucosae or visceral organs. Three quarters of KS cases occur in sub-Saharan Africa (SSA) as geographic variation is explained by the disparate prevalence of KS-associated herpes virus (KSHV), which is the underlying cause of this disease. It can infect endothelial and/or mesenchymal cells that consequently transdifferentiate to an intermediate state. KSHV establishes a latent phase in host cells in which latency proteins and various non-coding RNAs (ncRNAs) play a complex role in proliferation and angiogenesis. It also undergoes periods of sporadic lytic reactivation triggered by various biological signals in which lytic stage proteins modulate host cell signaling pathways and are key in KS progression. Complex interactions with the microenvironment with production of inflammatory cytokines with paracrine signaling is a standout feature of KS development and maintenance. KSHV impairs the immune response by various mechanisms such as the degradation of a variety of proteins involved in immune response or binding to cellular chemokines. Treatment options include classical chemotherapy, but other novel therapies are being investigated.

MEK1/2 inhibition transiently alters the tumor immune microenvironment to enhance immunotherapy efficacy against head and neck cancer.

BACKGROUND: Although the mitogen-activated protein kinases (MAPK) pathway is hyperactive in head and neck cancer (HNC), inhibition of MEK1/2 in HNC patients has not shown clinically meaningful activity. Therefore, we aimed to characterize the effect of MEK1/2 inhibition on the tumor microenvironment (TME) of MAPK-driven HNC, elucidate tumor-host interaction mechanisms facilitating immune escape on treatment, and apply rationale-based therapy combination immunotherapy and MEK1/2 inhibitor to induce tumor clearance. METHODS: Mouse syngeneic tumors and xenografts experiments were used to analyze tumor growth in vivo. Single-cell cytometry by time of flight, flow cytometry, and tissue stainings were used to profile the TME in response to trametinib (MEK1/2 inhibitor). Co-culture of myeloid-derived suppressor cells (MDSC) with CD8+ T cells was used to measure immune suppression. Overexpression of colony-stimulating factor-1 (CSF-1) in tumor cells was used to show the effect of tumor-derived CSF-1 on sensitivity to trametinib and anti-programmed death- 1 (αPD-1) in mice. In HNC patients, the ratio between CSF-1 and CD8A was measured to test the association with clinical benefit to αPD-1 and αPD-L1 treatment. RESULTS: Using preclinical HNC models, we demonstrated that treatment with trametinib delays HNC initiation and progression by reducing tumor cell proliferation and enhancing the antitumor immunity of CD8+ T cells. Activation of CD8+ T cells by supplementation with αPD-1 antibody eliminated tumors and induced an immune memory in the cured mice. Mechanistically, an early response to trametinib treatment sensitized tumors to αPD-1-supplementation by attenuating the expression of tumor-derived CSF-1, which reduced the abundance of two CSF-1R+CD11c+ MDSC populations in the TME. In contrast, prolonged treatment with trametinib abolished the antitumor activity of αPD-1, because tumor cells undergoing the epithelial to mesenchymal transition in response to trametinib restored CSF-1 expression and recreated an immune-suppressive TME. CONCLUSION: Our findings provide the rationale for testing the trametinib/αPD-1 combination in HNC and highlight the importance of sensitizing tumors to αPD-1 by using MEK1/2 to interfere with the tumor-host interaction. Moreover, we describe the concept that treatment of cancer with a targeted therapy transiently induces an immune-active microenvironment, and supplementation of immunotherapy during this time further activates the antitumor machinery to cause tumor elimination.

Longitudinal assessment of PD-L1 expression and gene expression profiles in patients with head and neck cancer reveals temporal heterogeneity.

BACKGROUND: Programmed death-ligand 1 (PD-L1) is the most validated predictive biomarker used for the treatment of head and neck squamous cell carcinoma (HNSCC) with immune checkpoint inhibitors (ICI). Several gene expression-based signatures surrogate of the activation of IFN-gamma pathway and of the presence of tertiary lymphoid structures (TLS) have also been proposed as potential biomarkers. While they may have a potential therapeutic implication, the longitudinal changes of either PD-L1 or gene expression profiles between the initial and recurrent HNSCC lesions is unknown. METHODS: PD-L1 immunohistochemistry (IHC) and targeted RNA-sequencing of 2,549 transcripts were analyzed on paired specimens from the initial diagnosis and recurrent HNSCC. PD-L1 status was defined using the combined positive score (CPS). PD-L1 mRNA levels were compared with protein expression levels by IHC. Enrichment scores of surrogate signatures for TLS and IFN-gamma (IFN-γ) pathway activation were computed using the single sample gene set enrichment analysis (ssGSEA). RESULTS: PD-L1 status was 64% (21/33) concordant between the initial and recurrent lesions using a CPS 1 threshold and 67% (22/33) concordant using a CPS 20 threshold. CPS score was associated with PD-L1 gene expression levels. There was a 43% (15/35) and 66% (23/35) concordance for the IFN-γ and TLS signature scores, respectively. CONCLUSION: Our study reveals temporal heterogeneity of PD-L1 status and TLS/IFN-γ gene expression surrogates in HNSCC that need to be considered when interpreting biomarker studies.

Precision Medicine Approaches to Overcome Resistance to Therapy in Head and Neck Cancers.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most incident cancer worldwide. More than half of HNSCC patients experience locoregional or distant relapse to treatment despite aggressive multimodal therapeutic approaches that include surgical resection, radiation therapy, and adjuvant chemotherapy. Before the arrival of immunotherapy, systemic chemotherapy was previously employed as the standard first-line protocol with an association of cisplatin or carboplatin plus 5-fluorouracil plus cetuximab (anti-EFGR antibody). Unfortunately, acquisition of therapy resistance is common in patients with HNSCC and often results in local and distant failure. Despite our better understanding of HNSCC biology, no other molecular-targeted agent has been approved for HNSCC. In this review, we outline the mechanisms of resistance to the therapeutic strategies currently used in HNSCC, discuss combination treatment strategies to overcome them, and summarize the therapeutic regimens that are presently being evaluated in early- and late-phase clinical trials.

Hyperprogression and impact of tumor growth kinetics after PD1/PDL1 inhibition in head and neck squamous cell carcinoma.

Background: Hyperprogressive disease (HPD) rate in head and neck squamous cell carcinoma (HNSCC) patients treated with immune checkpoint inhibitors (ICI) was determined using tumor growth kinetics (TGK) and compared with rapidly progressive screen-failure (SF) patients. The impact of TGK on outcomes with salvage chemotherapy (SCT) was also evaluated. Results: HPD was found in 22/120 (18%) patients. Median TGK before the onset of immunotherapy (TGKpre) was 2.7 for SF patients and 4.8 for HPD patients, with no significant difference (p = 0.17). Disease control rate after initial progressive disease on ICI was 86% with SCT in case of tumor growth deceleration vs 39% in case of tumor growth acceleration. Conclusions: HPD was frequent, but TGK of HPD patients treated with ICI did not differ from SF patients, suggesting that there is no relevant causal relationship between HPD and ICI. After initial PD with ICI, tumor growth deceleration was associated with better outcomes, indicating that TGKR might be useful to detect late responders, meriting prospective investigations. Materials and Methods: TGK ratio (TGKR) was defined as the ratio of TGK on ICI (TGKpost) to TGKpre. HPD was defined as TGKR ≥ 2. TGKR >1 indicated tumor growth acceleration, while 0 < TGKR < 1 indicated tumor deceleration.

Induction chemotherapy in head and neck cancers: Results and controversies.

Standard treatment for locally advanced head and neck squamous cell carcinoma (LAHNSCC) consists mainly of concurrent chemoradiation (CCR) but induction chemotherapy (IC) by docetaxel-cisplatin-fluorouracil (TPF), followed by CCR, is a strong option. Comparative trials suggest that IC and CCR are equivalent, and some trials suggest superiority of IC, whereas none shows inferiority. IC might have less interest in oropharyngeal cancer (more often linked to HPV infection). When functional laryngeal preservation is the patient's priority, essays strongly suggest that IC is the best treatment. There is little data about a less toxic regimen of IC, but several schemes are promising and need to be developed. An early selection of responders to IC by metabolic imaging must be considered. Intensification attempts with cetuximab were too toxic and unsafe, but trials with immunotherapy are ongoing to enhance TPF efficacy. After IC, CCR either with cetuximab or cisplatin seems to be equally effective.

Induction Chemotherapy in Head and Neck Squamous Cell Carcinoma: A Question of Belief.

Induction chemotherapy (IC) in locally advanced head and neck squamous cell carcinoma (LA HNSCC) has been used for decades. However, its role is yet to be clearly defined outside of larynx preservation. Patients with high risk of distant failure might potentially benefit from sequential treatment. It is now widely accepted that TPF (docetaxel, cisplatin, and fluorouracil) is the standard IC regimen. Essays that have compared this approach with the standard of care, concurrent chemoradiotherapy (CCRT), are mostly inconclusive. Radiotherapy (RT) can be used in the post-IC setting and be sensitized by chemotherapy or cetuximab. Again, no consensus exists but there seems to be trend in favor of potentiation by cisplatin. Less toxic schemes of IC are tested as toxicity is a major issue with TPF. IC might have an interesting role in human papilloma virus (HPV)-related LA HNSCC and lead to CCRT de-escalation.

Carboplatin in combination with weekly Paclitaxel as first-line therapy in patients with recurrent/metastatic head and neck squamous cell carcinoma unfit to EXTREME schedule.

The standard first-line treatment in recurrent/metastatic head and neck squamous cell carcinoma combines Cisplatin, 5 Fluorouracil and Cetuximab, but many patients aren't eligible. We retrospectively evaluated the efficacy and the tolerability of Carboplatin and Paclitaxel in this indication, mostly in patients unfit to Cisplatin. Paclitaxel (80mg/m2) was administered at day 1, 8 and 15 and Carboplatin area under the curve 5 at day 1, repeated every 28 days, for 6 cycles. Carboplatin could be administered at area under the curve 2 at day 1, 8 and 15. 117 patients received this association at our institution, 94 of those were ineligible to cisplatin due to severe comorbidities, age >70years or Performance status >1. The overall response rate was 40%. The median progression free survival for patients ineligible to Cisplatin was 4.4 months [95% CI; 3.4; 5.0] and the median overall survival was 8 months [95% CI; 5.4-10.7]. The most frequent toxicities were hematologic, with 94 grade ≥ 3, mostly in patients who received monthly Carboplatin. Our study shows Carboplatin and Paclitaxel in first-line in recurrent/metastatic head and neck squamous cell carcinoma appear efficient for patients ineligible to Cisplatin and safe when both drugs are weekly administered.

L'immunothérapie dans les cancers ORL.

IMMUNOTHERAPY IN HEAD AND NECK CANCERS: Immunotherapy wave has also touched head and neck cancer. In recurrent or metastatic disease, checkpoint inhibitors (anti PD-1/PD-L1) are approved in 2nd line with a clear benefit on overall survival and quality of life. Multiple clinical studies are in progress in both palliative and curative intent, combined or not with other checkpoint inhibitor (anti-CTLA4) or other standard therapies (radiotherapy, chemotherapy). It is essential to define which patients will benefit from immunotherapy, according to robust biomarkers, in order to increase risk benefit balance by decreasing side effects and selecting those who respond the most. Here we present an overview of immunotherapy in 2018 in head and neck squamous cell cancer.

Nivolumab in recurrent/metastatic head and neck cancers.

Head and neck cancer is an immunosuppressive disease, with a high proportion expressing PD-L1. Until recently, options were lacking in second line. Prognosis is poor especially for patients who progress during chemotherapy with survival often inferior to 6 months. Nivolumab is the only anti-PD-1 agent to prolong survival in the second-line setting and is now the standard option since the CheckMate-141 trial. Treatment is generally well tolerated, patients seem to have a better quality of life when compared with chemotherapy. Markers of efficacy are lacking even if some data are emerging. Different combinations of immunotherapy are ongoing. Hyperprogression is a phenomenon associated with poor outcome and might be the consequence of anti-PD-1 treatment but this is yet to be proven.

Chemotherapy for recurrent/metastatic head and neck cancers.

Chemotherapy is the only option of treatment for most patients presenting with a recurrent and/or metastatic head and neck squamous cell carcinoma. The triple association of cisplatin, 5-fluorouracile, and cetuximab is still the current standard for fit patients. Other schemes are currently being compared with this protocol in ongoing trials and the association of cisplatin, docetaxel, and cetuximab appears to be the most efficient. The human papilloma virus is very likely a favorable prognostic factor. Immunotherapy with nivolumab or pembrolizumab is now a new standard of treatment in second line after yielding an improvement in overall survival, but predictive markers of efficacy are needed to refine the selection of patients. The combination of paclitaxel and buparlisib appears to be promising.

Chemotherapy for localized head and neck squamous cell cancers.

Concomitant chemotherapy with cisplatin (100 mg/m every 3 weeks) improves outcome for high-risk patients in the postoperative setting and for inoperable disease. Toxicity is increased. Other schemes of potentiation are sometimes used to reduce toxicity, but efficiency is diminished. Cetuximab also improves outcome, but there has been no direct comparison with cisplatin. Immunotherapy is currently being evaluated in association with radiation therapy. Trials are ongoing to evaluate the impact of de-escalation for human papillomavirus-positive patients. The association of docetaxel, cisplatin, and 5-fluorouracil is the standard of induction; it is also the standard treatment for laryngeal preservation. Many trials have attempted to compare the concomitant approach with the sequential treatment; none have managed to show a difference between the two. After induction chemotherapy, there is still no standard of potentiation of radiotherapy.