The Differential Impact of SRC Expression on the Prognosis of Patients with Head and Neck Squamous Cell Carcinoma

Aberrant SRC expression and activation is frequently detected in multiple cancers, and hence, targeting SRC has emerged as a promising therapeutic strategy. Different SRC inhibitors have demonstrated potent anti-tumor activity in preclinical models, although they largely lack clinical efficacy as monotherapy in late-stage solid tumors, including head and neck squamous cell carcinomas (HNSCC). Adequate selection and stratification of patients who may respond to and benefit from anti-SRC therapies is therefore needed to guide clinical trials and treatment efficacy. This study investigates the prognostic significance of active SRC expression in a homogeneous cohort of 122 human papillomavirus (HPV)-negative, surgically treated HNSCC patients. Immunohistochemical evaluation of the active form of SRC by means of anti-SRC Clone 28 monoclonal antibody was specifically performed and subsequently correlated with clinical data. The expression of p-SRC (Tyr419), total SRC, and downstream SRC effectors was also analyzed. Our results uncovered striking differences in the prognostic relevance of SRC expression in HNSCC patients depending on the tumor site. Active SRC expression was found to significantly associate with advanced disease stages, presence of lymph node metastasis, and tumor recurrences in patients with laryngeal tumors, but not in the pharyngeal subgroup. Multivariate Cox analysis further revealed active SRC expression as an independent predictor of cancer-specific mortality in patients with laryngeal carcinomas. Concordantly, expression of p-SRC (Tyr419) and the SRC substrates focal adhesion kinase (FAK) and the Arf GTPase-activating protein ASAP1 also showed specific associations with poor prognosis in the larynx. These findings could have important implications in ongoing Src family kinase (SFK)-based clinical trials, as these new criteria could help to improve patient selection and develop biomarker-stratified trials

YES1 drives lung cancer growth and progression and predicts sensitivity to dasatinib

Rationale: The characterization of new genetic alterations is essential to assign effective personalized therapies in non–small cell lung cancer (NSCLC). Furthermore, finding stratification biomarkers is essential for successful personalized therapies. Molecular alterations of YES1, a member of the SRC (proto-oncogene tyrosine-protein kinase Src) family kinases (SFKs), can be found in a significant subset of patients with lung cancer. Objectives: To evaluate YES1 (v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1) genetic alteration as a therapeutic target and predictive biomarker of response to dasatinib in NSCLC. Methods: Functional significance was evaluated by in vivo models of NSCLC and metastasis and patient-derived xenografts. The efficacy of pharmacological and genetic (CRISPR [clustered regularly interspaced short palindromic repeats]/Cas9 [CRISPR-associated protein 9]) YES1 abrogation was also evaluated. In vitro functional assays for signaling, survival, and invasion were also performed. The association between YES1 alterations and prognosis was evaluated in clinical samples. Measurements and Main Results: We demonstrated that YES1 is essential for NSCLC carcinogenesis. Furthermore, YES1 overexpression induced metastatic spread in preclinical in vivo models. YES1 genetic depletion by CRISPR/Cas9 technology significantly reduced tumor growth and metastasis. YES1 effects were mainly driven by mTOR (mammalian target of rapamycin) signaling. Interestingly, cell lines and patient-derived xenograft models with YES1 gene amplifications presented a high sensitivity to dasatinib, an SFK inhibitor, pointing out YES1 status as a stratification biomarker for dasatinib response. Moreover, high YES1 protein expression was an independent predictor for poor prognosis in patients with lung cancer. Conclusions: YES1 is a promising therapeutic target in lung cancer. Our results provide support for the clinical evaluation of dasatinib treatment in a selected subset of patients using YES1 status as predictive biomarker for therapy

SRC family kinase (SFK) inhibitor dasatinib improves the antitumor activity of anti-PD-1 in NSCLC models by inhibiting Treg cell conversion and proliferation

Introduction The use of immune-checkpoint inhibitors has drastically improved the management of patients with non-small cell lung cancer (NSCLC), but innate and acquired resistances are hurdles needed to be solved. Immunomodulatory drugs that can reinvigorate the immune cytotoxic activity, in combination with antiprogrammed cell death 1 (PD-1) antibody, are a great promise to overcome resistance. We evaluated the impact of the SRC family kinases (SFKs) on NSCLC prognosis, and the immunomodulatory effect of the SFK inhibitor dasatinib, in combination with anti-PD-1, in clinically relevant mouse models of NSCLC. Methods A cohort of patients from University Clinic of Navarra (n=116) was used to study immune infiltrates by multiplex immunofluorescence (mIF) and YES1 protein expression in tumor samples. Publicly available resources (TCGA, Km Plotter, and CIBERSORT) were used to study patient's survival based on expression of SFKs and tumor infiltrates. Syngeneic NSCLC mouse models 393P and UNSCC680AJ were used for in vivo drug testing. Results Among the SFK members, YES1 expression showed the highest association with poor prognosis. Patients with high YES1 tumor levels also showed high infiltration of CD4+/FOXP3+ cells (regulatory T cells (Tregs)), suggesting an immunosuppressive phenotype. After testing for YES1 expression in a panel of murine cell lines, 393P and UNSCC680AJ were selected for in vivo studies. In the 393P model, dasatinib+anti-PD-1 treatment resulted in synergistic activity, with 87% tumor regressions and development of immunological memory that impeded tumor growth when mice were rechallenged. In vivo depletion experiments further showed that CD8+ and CD4+ cells are necessary for the therapeutic effect of the combination. The antitumor activity was accompanied by a very significant decrease in the number of Tregs, which was validated by mIF in tumor sections. In the UNSCC680AJ model, the antitumor effects of dasatinib+anti-PD-1 were milder but similar to the 393P model. In in vitro assays, we demonstrated that dasatinib blocks proliferation and transforming growth factor beta-driven conversion of effector CD4+ cells into Tregs through targeting of phospholymphocyte-specific protein tyrosine kinase and downstream effectors pSTAT5 and pSMAD3. Conclusions YES1 protein expression is associated with increased numbers of Tregs in patients with NSCLC. Dasatinib synergizes with anti-PD-1 to impair tumor growth in NSCLC experimental models. This study provides the preclinical rationale for the combined use of dasatinib and PD-1/programmed death-ligand 1 blockade to improve outcomes of patients with NSCLC

YES1 drives lung cancer growth and progression and predicts sensitivity to dasatinib

Rationale: The characterization of new genetic alterations is essential to assign effective personalized therapies in non–small cell lung cancer (NSCLC). Furthermore, finding stratification biomarkers is essential for successful personalized therapies. Molecular alterations of YES1, a member of the SRC (proto-oncogene tyrosine-protein kinase Src) family kinases (SFKs), can be found in a significant subset of patients with lung cancer. Objectives: To evaluate YES1 (v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1) genetic alteration as a therapeutic target and predictive biomarker of response to dasatinib in NSCLC. Methods: Functional significance was evaluated by in vivo models of NSCLC and metastasis and patient-derived xenografts. The efficacy of pharmacological and genetic (CRISPR [clustered regularly interspaced short palindromic repeats]/Cas9 [CRISPR-associated protein 9]) YES1 abrogation was also evaluated. In vitro functional assays for signaling, survival, and invasion were also performed. The association between YES1 alterations and prognosis was evaluated in clinical samples. Measurements and Main Results: We demonstrated that YES1 is essential for NSCLC carcinogenesis. Furthermore, YES1 overexpression induced metastatic spread in preclinical in vivo models. YES1 genetic depletion by CRISPR/Cas9 technology significantly reduced tumor growth and metastasis. YES1 effects were mainly driven by mTOR (mammalian target of rapamycin) signaling. Interestingly, cell lines and patient-derived xenograft models with YES1 gene amplifications presented a high sensitivity to dasatinib, an SFK inhibitor, pointing out YES1 status as a stratification biomarker for dasatinib response. Moreover, high YES1 protein expression was an independent predictor for poor prognosis in patients with lung cancer. Conclusions: YES1 is a promising therapeutic target in lung cancer. Our results provide support for the clinical evaluation of dasatinib treatment in a selected subset of patients using YES1 status as predictive biomarker for therapy