Erratum to "Mixed tumors of the canine mammary glands: Evaluation of prognostic factors, treatment, and overall survival" [7C (June 2019) 100039].

[This corrects the article DOI: 10.1016/j.vas.2018.09.003.].

Identification of PIKfyve kinase as a target in multiple myeloma.

The cellular cytotoxicity of APY0201, a PIKfyve inhibitor, against multiple myeloma was initially identified in an unbiased in vitro chemical library screen. The activity of APY0201 was confirmed in all 25 cell lines tested and in 40% of 100 ex vivo patient-derived primary samples, with increased activity in primary samples harboring trisomies and lacking t(11;14). The broad anti-multiple myeloma activity of PIKfyve inhibitors was further demonstrated in confirmatory screens and showed the superior potency of APY0201 when compared to the PIKfyve inhibitors YM201636 and apilimod, with a mid-point half maximal effective concentration (EC50) at nanomolar concentrations in, respectively, 65%, 40%, and 5% of the tested cell lines. Upregulation of genes in the lysosomal pathway and increased cellular vacuolization were observed in vitro following APY0201 treatment, although these cellular effects did not correlate well with responsiveness. We confirm that PIKfyve inhibition is associated with activation of the transcription factor EB, a master regulator of lysosomal biogenesis and autophagy. Furthermore, we established an assay measuring autophagy as a predictive marker of APY0201 sensitivity. Overall, these findings indicate promising activity of PIKfyve inhibitors secondary to disruption of autophagy in multiple myeloma and suggest a strategy to enrich for likely responders.

Versican and Tumor-Associated Macrophages Promotes Tumor Progression and Metastasis in Canine and Murine Models of Breast Carcinoma.

Versican and tumor-associated macrophages (TAMs) are involved in growth and metastases in several cancers. Here, we investigated the potential role of versican, a matrix proteoglycan, and its correlation with TAMs infiltrates in different stages of two different breast cancer models: spontaneous canine mammary gland carcinomas and the murine 4T1 breast cancer model. The stromal versican expression was correlated with TAMs accumulation in tumors with an advanced stage from spontaneous canine mammary carcinoma samples. Versican expression in mice, identified in late stages of tumor progression, was associated to a high number of peri-tumoral infiltrating TAMs. Indeed, TAMs were related to a pro-inflammatory and pro-angiogenic state in the primary tumor. Furthermore, TAMs accumulation was related to versican expression in the lungs and an increased number of pulmonary metastatic nodules with pulmonary mechanical dysfunction, which was due to leukocyte influx in the airways and elevated growth factor levels in the microenvironment. Thus, we suggest that versican and TAMs as attractive targets for breast cancer therapy.

Identification of lenalidomide resistance pathways in myeloma and targeted resensitization using cereblon replacement, inhibition of STAT3 or targeting of IRF4.

To understand immunomodulatory drug (IMiD) resistance in multiple myeloma (MM), we created isogenic human multiple myeloma cell lines (HMCLs) sensitive and resistant to lenalidomide, respectively. Four HMCLs were demonstrated to be resistant to all IMiDs including lenalidomide, pomalidomide, and CC-220, but not to Bortezomib. In three HMLCs (MM.1.SLenRes, KMS11LenRes and OPM2LenRes), CRBN abnormalities were found, including chromosomal deletion, point mutation, and low CRBN expression. The remaining HMCL, XG1LenRes, showed no changes in CRBN but exhibited CD147 upregulation and impaired IRF4 downregulation after lenalidomide treatment. Depletion of CD147 in XG1LenRes and three additional HMCLs had no significant impact on MM viability and lenalidomide response. Further analysis of XG1LenRes demonstrated increased IL6 expression and constitutive STAT3 activation. Inhibition of STAT3 with a selective compound (PB-1-102) re-sensitized XG1LenRes to lenalidomide. Since XG1LenRes harbors a truncated IRF4 that is not downregulated by lenalidomide, we targeted IRF4/MYC axis with a selective inhibitor of the bromodomain of CBP/EP300 (SGC-CBP30), which restored lenalidomide response in XG1LenRes. This strategy also appeared to be more broadly applicable as SGC-CBP30 could re-sensitize two resistant HMCLs with low but detectable CRBN expression to lenalidomide, suggesting that targeting CBP/E300 is a promising approach to restore IMiD sensitivity in MM with detectable CRBN expression.

Mixed tumors of the canine mammary glands: Evaluation of prognostic factors, treatment, and overall survival.

Mixed tumors are the most frequent mammary gland neoplasms in bitches; however, studies that thoroughly describe their clinicopathological data, treatment approaches, and the survival of bitches with mixed tumors are scarce. This study evaluated the epidemiological and clinicopathological data, prognostic factors, and therapeutic approaches for bitches with mixed tumors. In all, 162 benign mixed tumors, 682 carcinomas in mixed tumors, and 60 carcinosarcomas were included. Regarding tumor size, T3 lesions were predominantly associated with carcinosarcomas, while T1 and T2 lesions occurred more frequently in benign mixed tumors and in carcinomas in mixed tumors. Based on clinical staging, most bitches with benign mixed tumors presented with stage I tumors; 92% of bitches with carcinomas in mixed tumors presented with stage I-III tumors, while 8% presented with stage IV-V tumors; and 70% of bitches with carcinosarcomas presented with stage I-III tumors, while 30% presented with stage IV-V tumors. Surgery was curative for bitches with benign mixed tumors and for those with stage I-III carcinomas in mixed tumors. Combination therapy in bitches with carcinomas in mixed tumors (IV-V) and carcinosarcomas resulted in a higher overall survival compared with bitches who underwent surgery only. Carcinosarcomas presented higher relapse rates and distant metastases than carcinomas in mixed tumors did.

Adjuvant Thalidomide and Metronomic Chemotherapy for the Treatment of Canine Malignant Mammary Gland Neoplasms.

BACKGROUND/AIM: The aim of the present study was to evaluate a multimodal approach for the treatment of canine malignant mammary gland neoplasms, including surgery, chemotherapy, thalidomide, and metronomic chemotherapy (MC). MATERIALS AND METHODS: Fifty-eight female dogs were submitted to four different treatments: surgery; surgery with chemotherapy; surgery with chemotherapy and thalidomide; and surgery with chemotherapy and metronomic chemotherapy and overall survival was evaluated. RESULTS: No statistical difference was found in the proliferative index and microvessel density of primary neoplasms and distant metastases following thalidomide treatment. Diffuse intense inflammatory infiltrate was predominant in primary tumors and diffuse moderate inflammatory infiltrate in metastatic lesions. No statistically significant difference was observed in median survival time (MST) between treatment groups when including all clinical stages (p=0.3177). However, animals diagnosed with distant metastasis treated with surgery and chemotherapy associated with thalidomide or MC presented longer MST when compared to animals treated only with surgery or surgery and chemotherapy (p<0.0001). CONCLUSION: The proposed multimodal therapy protocols including antiangiogenic and immunomodulatory therapies demonstrated a clinical benefit for patients in advanced clinical stages.

Relationship between the inflammatory tumor microenvironment and different histologic types of canine mammary tumors.

Mammary neoplasms are the tumors with higher incidence in female dogs. Among the factors that contribute for the development of this and other neoplasms, the inflammatory tumor microenvironment plays a crucial role. Several studies reported important roles for lymphocytes, macrophages, plasma cells, neutrophils, eosinophils and mast cells in this context. In the present study, our aim was to evaluate the number of profile cells of inflammatory cells and area of tumor fibrosis and the relation of these features with canine mammary tumors of different histologic and clinical presentation (benign mixed tumor, carcinoma in mixed tumor, solid carcinoma and tubular carcinoma) Counting and staining of inflammatory cells and tumor fibrosis were performed through histochemistry, while counting and staining of CD4+, TCD8+ and FOXP3+ lymphocytes were performed through immunohistochemistry. Statistical analysis of the association between densities of inflammatory cells, tumor fibrosis and histologic types revealed significant difference for plasma cells (p = .035), neutrophils (p = .0113), macrophages (p = .0047), and tumor fibrosis (p = .05). The found data suggest associations between high number of neutrophils and aggressive mammary tumors, between high densities of plasma cells, macrophages and CD8+ cells and between low number of profile cells of CD4+ cells and less aggressive tumors. Larger areas of tumor fibrosis showed relation to more aggressive canine mammary tumors.

Cytologic analysis of the mammary papillar discharge in a canine micropapillary carcinoma.

This is a report on the cytologic analysis of the mammary papillar discharge in a 7-year-old female Doberman dog with an invasive micropapillary carcinoma. Cytologic evaluation of nipple discharge is a well-known method for the rapid diagnosis of breast cancer in women. However, there is no previous report regarding the use of this technique for assessing mammary tumors in dogs. The aim of this study was to describe the use of mammary papillar discharge cytology for diagnosing a micropapillary carcinoma in a dog. Cytologically, evaluation of the papillar discharge revealed cells arranged in clusters in a papillary pattern or in a morula-like arrangement, suggesting the diagnosis of a micropapillary carcinoma, which was subsequently confirmed by histopathology. Thus, mammary papillar discharge cytology should be considered as an ancillary method for evaluating mammary diseases in dogs.

Use of surgery and carboplatin in feline malignant mammary gland neoplasms with advanced clinical staging.

BACKGROUND/AIM: Feline mammary carcinomas (FMCs) are characterized by poor prognosis and little progress has been made in extending patient survival. The aim of the study was to compare overall survival periods of FMCs submitted to different treatment protocols, including surgery and adjuvant chemotherapy. MATERIALS AND METHODS: Analysis of conventional surgical excision alone or in association with adjuvant chemotherapy with carboplatin in sixteen cats diagnosed with stage III and grade II or III FMCs was performed. RESULTS: Patients treated with surgery and chemotherapy presented a longer overall survival (OS) than those treated only with surgery, however, no statistical difference was observed when comparing both treatments (p=0.883). CONCLUSION: Therapeutic benefit of carboplatin remains invalidated for FMCs and further investigation regarding adjuvant therapies are warranted. Surgery remains as the gold treatment in FMCs.

Canine malignant mammary gland neoplasms with advanced clinical staging treated with carboplatin and cyclooxygenase inhibitors.

Surgery remains the treatment of choice for female dogs with mammary gland tumors. Chemotherapy is not commonly used as an adjuvant therapy. Cyclooxygenase 2 (COX-2) has been related to angiogenesis development in tumors, disease progression and worse prognosis. The aim of this prospective study was to compare overall survival periods of female dogs diagnosed with advanced mammary tumors submitted to different treatment protocols, including surgery, chemotherapy and cyclooxygenase inhibitors. Twenty-nine female dogs were evaluated and treated with four different protocols. The overall survival of patients with low COX-2 scores was longer when compared to patients with high COX-2 scores. Different proposed adjuvant treatments associated with surgery led to a statistically significant longer overall survival when compared to surgical treatment alone. Canine patients presenting malignant mammary gland neoplasms with advanced clinical staging should be submitted to complementary therapeutic medication based on clinical staging and immunophenotypical characteristics of the disease.