The immune microenvironment of HPV-negative oral squamous cell carcinoma from never-smokers and never-drinkers patients suggests higher clinical benefit of IDO1 and PD1/PD-L1 blockade.

BACKGROUND: Never-smokers and never-drinkers patients (NSND) suffering from oral squamous cell carcinoma (OSCC) are epidemiologically different from smokers drinkers (SD). We therefore hypothesized that they harbored distinct targetable molecular alterations. PATIENTS AND METHODS: Data from The Cancer Genome Atlas (TCGA) (discovery set), Gene Expression Omnibus and Centre Léon Bérard (CLB) (three validation sets) with available gene expression profiles of HPV-negative OSCC from NSND and SD were mined. Protein expression profiles and genomic alterations were also analyzed from TCGA, and a functional pathway enrichment analysis was carried out. Formalin-fixed paraffin-embedded samples from 44 OSCC including 20 NSND and 24 SD treated at CLB were retrospectively collected to perform targeted-sequencing of 2559 transcripts (HTG EdgeSeq system), and CD3, CD4, CD8, IDO1, and PD-L1 expression analyses by immunohistochemistry (IHC). Enrichment of a six-gene interferon-γ signature of clinical response to pembrozulimab (PD-1 inhibitor) was evaluated in each sample from all cohorts, using the single sample gene set enrichment analysis method. RESULTS: A total of 854 genes and 29 proteins were found to be differentially expressed between NSND and SD in TCGA. Functional pathway analysis highlighted an overall enrichment for immune-related pathways in OSCC from NSND, especially involving T-cell activation. Interferon-γ response and PD1 signaling were strongly enriched in NSND. IDO1 and PD-L1 were overexpressed and the score of response to pembrolizumab was higher in NSND than in SD, although the mutational load was lower in NSND. IHC analyses in the CLB cohort evidenced IDO1 and PD-L1 overexpression in tumor cells that was associated with a higher rate of tumor-infiltrating T-cells in NSND compared with SD. CONCLUSION: The main biological and actionable difference between OSCC from NSND and SD lies in the immune microenvironment, suggesting a higher clinical benefit of PD-L1 and IDO1 inhibition in OSCC from NSND.

Canarypox virus expressing wild type p53 for gene therapy in murine tumors mutated in p53.

The antitumor activity of a recombinant canarypox virus expressing wild type murine p53 (ALVAC-p53) was investigated in two murine syngeneic tumors harboring an endogenous p53 mutation (CMS4 and TS/A). Direct intratumor injections of ALVAC-p53 in CMS4 pre-established subcutaneous tumors induced total tumor regression in 66% of mice. Furthermore, 100% of the cured mice was protected against a contralateral subsequent challenge with the parental tumor cells. The intravenous treatment of experimental lung metastasis by ALVAC-p53 also induced significant tumor growth inhibition in both models. The antitumor effect of ALVAC-p53 was only observed in immunocompetent animals and was associated with the generation of a specific antitumor immune response. ALVAC-p53 induced the expression of a functional p53 wild type protein as demonstrated by up-regulation of p21waf1 and induction of apoptosis. A vaccine strategy using intravenous or subcutaneous ALVAC-p53/NYVAC-p53 prime boost protocol failed to induce CTL against p53 wild type used as target tumor antigen, and failed to protect mice against challenge with the mutated tumor cells. The mechanism of the curative and protective effects observed after direct intratumor injections results from the induction of a specific antitumor response directed against other antigens than p53. Our results suggest that the local induction of tumor apoptosis, combined with the adjuvant effect of ALVAC vector, enhances the immunogenicity of the intratumor environment and allows induction of specific antitumor immune response.

[Cryosurgery of liver neoplasms]. / La cryochirurgie des tumeurs du foie.

Cryosurgery is the in situ destruction of tissue using subzero temperatures. Its use for the treatment of some unresectable liver tumors has been clearly established as a therapeutic option. Experimental studies have demonstrated the feasibility of freezing of large liver volumes without any major metabolic and hemorrhagic complications. Modern cryosurgery has received substantial impetus from the development of automated cryosurgical apparatuses using liquid nitrogen. Intraoperative ultrasound has enhanced the process by enabling visualization of tissue freezing and ensuring precise and optimal treatment of the tumor. Clinical reports of cryosurgery for liver primary tumors and metastases have confirmed the safety of the procedure. Major complications include myoglobinuria, coagulopathy and pleural effusions. The benefit of cryosurgery is that it broadens the number of patients that can be brought to surgery and can potentially become disease-free.

Hepatocarcinoma-specific mutant p53-249ser induces mitotic activity but has no effect on transforming growth factor beta 1-mediated apoptosis.

Mutations affecting the p53 gene abrogate its tumor suppressor activity. It is, however, unclear whether such mutations can generate mutant p53 proteins with an intrinsic transforming ability. More importantly, the mechanism(s) by which they exert such activity is unknown. We report here that p53-deficient hepatoma cells (Hep3B) transfected with mutant p53-249ser (codon 249 Arg-->Ser) acquire a new phenotype with an increased in vitro survival and mitotic activity. However, such a phenotypic change is not sufficient to cause a major shift in the poor tumorigenic potential of these cells. This is apparently due to transforming growth factor beta 1-mediated apoptotic death of Hep3B cells which is not affected by the expression of p53-249ser.

[Prognostic value of lympho node micrometastases detected by immunohistochemistry. Study of 168 cases of breast cancer with a 10-year follow-up]. / Valeur pronostique des micrométastases ganglionnaires détectées par analyse immunohistochimique. A propos de 168 cas de carcinomes mammaires suivis pendant plus de 10 ans.

The authors reported a retrospective pathological study of 168 patients classified PT2N- treated by Patey mastectomy completed by axillary and internal mammary lymph node removal. The size of micrometastases ranged from 0.012 to 0.87 millimeters. All 2800 lymph nodes were examined, using successively HPS and IHC procedures. Detection of micrometastases has been improved by immunohistochemical staining on paraffin embedded sections using anticytokeratin MAb clone antiKL1. The 168 patients were divided into two groups. The first one included 31 patients IHC+ out of 168 (18.5%); there were 47 micrometastatic nodes with negatives nodes out of 2800 (1,67%). The second group included 137 patients (81.5%) out of 168 with negative nodes. If we consider the PT2N-clinical status, it appears a percentage of 16 to 20% of patients developing recurrence within ten years after surgical treatment. There was no significant difference concerning the disease--free survival at ten years. Variability in metastatic node involvement spread led us to distinguish 3 subgroups of uneven prognostic value. The relative risk of relapse ranged from 1 (ICH + 1) to 1.94 (ICH + 2 and 3) merged. Do PT2N- group with recurrence and ICH + group concern the same patients? We cannot statistically prove that micrometastatic nodes are a bad prognostic factor by further studies which are required.

[Detection of micrometastases in excised regional lymph nodes in cancer of the breast. Systematic use of KL1 anticytokeratin monoclonal antibodies in a prospective series of 120 T2 N- patients]. / Détection des micrométastases dans les curages ganglionnaires régionaux des cancers mammaires. Utilisation systématique de l'anticorps monoclonal anticytokératine KL1 sur une série prospective de 120 patients T2 N-.

A series of 120 patients (T2, No, N1a according to UICC classification) with mammary cancer treated by mastectomy and regional lymph node dissection, classified T2N-after Hemalun-Phloxine Safran (HPS) standard sections, have a positive reaction with immunohistochemical staining (IHM) using monoclonal antibodies (anti KL1) so that IHM improve the detection of lymph node metastases. 13 patients out of 120 presumed N-after HPS technic became positive with IHM staining. We examined 2108 lymph nodes and noticed 19 N+, the size of which was less than 2 millimeters. Microscopically, three main aspects are follows. Micrometastases made of clusters of malignant cells; micrometastases with single cells in file, and a composite aspect from both previous ones. Metastatic cells detected by anti KL1 have an excellent contrast due to clear nucleus surrounded by a large rim of dark cytoplasm. Although T2N-has a better prognosis than T2N+, 10 to 20% of patients relapsed within ten years after surgical treatment. It is important to determine whether the detection of occult micrometastases permits to predict recurrence. Is it a relevant correlation or not? if such a connection does'not exist, micrometastasis detection became irrelevant; on the contrary, if it exists, the therapists can launch on adequate adjuvant treatment - useful only - for patients with high risk of relapse.