sirolimus and Squamous-Cell-Carcinoma-of-Head-and-Neck

Patients with cetuximab-resistant, recurrent/metastatic head and neck squamous cell carcinoma (HNSCC) have poor outcomes. This study hypothesized that dual blockade of mammalian target of rapamycin and epidermal growth factor receptor (EGFR) would overcome cetuximab resistance on the basis of the role of phosphoinositide 3-kinase signaling in preclinical models of EGFR resistance.. In this multicenter, randomized clinical study, patients with recurrent/metastatic HNSCC with documented progression on cetuximab (in any line in the recurrent/metastatic setting) received 25 mg of temsirolimus weekly plus cetuximab at 400/250 mg/m. Eighty patients were randomized to therapy with TC or T alone. There was no difference for the primary outcome of median PFS (TC arm, 3.5 months; T arm, 3.5 months). The response rate was 12.5% in the TC arm (5 responses, including 1 complete response [2.5%]) and 2.5% in the T arm (1 partial response; P = .10). Responses were clinically meaningful in the TC arm (range, 3.6-9.1 months) but not in the T-alone arm (1.9 months). Fatigue, electrolyte abnormalities, and leukopenia were the most common grade 3 or higher adverse events and occurred in less than 20% of patients in both arms.. The study did not meet its primary endpoint of improvement in PFS. However, TC induced responses in cetuximab-refractory patients with good tolerability. The post hoc observation of activity in patients with acquired resistance (after prior benefit from cetuximab monotherapy) may warrant further investigation.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Agents, Immunological; Antineoplastic Combined Chemotherapy Protocols; Cetuximab; Drug Resistance, Neoplasm; ErbB Receptors; Female; Head and Neck Neoplasms; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Progression-Free Survival; Protein Kinase Inhibitors; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases

We studied the impact of mTOR signaling inhibition with rapamycin in head and neck squamous cell carcinoma (HNSCC) in the neoadjuvant setting. The goals were to evaluate the mTOR pathway as a therapeutic target for patients with advanced HNSCC, and the clinical safety, antitumor, and molecular activity of rapamycin administration on HNSCC.. Patients with untreated stage II-IVA HNSCC received rapamycin for 21 days (day 1, 15 mg; days 2-12, 5 mg) prior to definitive treatment with surgery or chemoradiation. Treatment responses were assessed clinically and radiographically with CT and FDG-PET. Pre- and posttreatment biopsies and blood were obtained for toxicity, immune monitoring, and IHC assessment of mTOR signaling, as well as exome sequencing.. Sixteen patients (eight oral cavity, eight oropharyngeal) completed rapamycin and definitive treatment. Half of patients were p16 positive. One patient had a pathologic complete response and four (25%) patients met RECIST criteria for response (1 CR, 3 PR, 12 SD). Treatment was well tolerated with no grade 4 or unexpected toxicities. No significant immune suppression was observed. Downstream mTOR signaling was downregulated in tumor tissues as measured by phosphorylation of S6 (. Rapamycin treatment was well tolerated, reduced mTOR signaling and tumor growth, and resulted in significant clinical responses despite the brief treatment duration, thus supporting the potential role of mTOR inhibitors in treatment regimens for HNSCC.

Topics: Animals; Apoptosis; Cell Line, Tumor; Class I Phosphatidylinositol 3-Kinases; Exome Sequencing; Female; Gene Expression Regulation, Neoplastic; Head and Neck Neoplasms; Humans; Male; Mice; Middle Aged; Neoadjuvant Therapy; Neoplasm Staging; Phosphorylation; Positron Emission Tomography Computed Tomography; Proto-Oncogene Proteins c-akt; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Activating events along the PI3K/mTOR pathway are common in head and neck squamous cell carcinomas (HNSCC), and preclinical studies suggest additive or synergistic effects when combining mTORC1 inhibitors with carboplatin and paclitaxel chemotherapy.. In this single-institution phase II study, the combination of temsirolimus 25 mg, carboplatin AUC 1.5, and paclitaxel 80 mg/m2 administered on days 1 and 8 of a 21-day cycle was evaluated in 36 patients with recurrent and/or metastatic (R/M) HNSCC. The primary end point was objective response rate after two cycles of treatment. Secondary end points include the safety and tolerability profile and overall survival. Correlative studies with exome mutational analysis were performed in pre-treatment biopsy samples from 21 patients.. Fifteen (41.7%) patients had an objective response, which were all partial responses, and 19 (52.3%) patients had stable disease as best response. The two patients who were designated as 'non-responders' were removed from study prior to two cycles of treatment, but are included in the efficacy and safety analyses. The median duration on study was 5.3 months and the median progression-free survival and overall survival were 5.9 months (95% confidence interval, 4.8-7.1) and 12.8 months (95% confidence interval, 9.8-15.8), respectively. The most common grade 3 and 4 adverse events were hematologic toxicities. Three (3.8%) patients developed neutropenic fever on study. Three of four patients with PIK3CA mutations experienced tumor regressions, and responses were also seen in patients with other genetic alterations in the PI3K/mTOR pathway.. The combination of temsirolimus with low-dose weekly carboplatin and paclitaxel appears to have meaningful clinical efficacy in the treatment of R/M HNSCC. This regimen has a relatively high response rate compared to other treatments evaluated in R/M HNSCC, and potential associations with genetic alterations in the PI3K/mTOR pathway should be further explored.

Topics: Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Carcinoma, Squamous Cell; Dose-Response Relationship, Drug; Drug Administration Schedule; Female; Head and Neck Neoplasms; Humans; Male; Middle Aged; Neoplasm Metastasis; Neoplasm Recurrence, Local; Paclitaxel; Sirolimus; Squamous Cell Carcinoma of Head and Neck

Squamous cell carcinoma of the head and neck (SCCHN) is a common disease, which has a poor prognosis after failure of therapy. Activation of the PI3K-AKT-mTOR axis is commonly detected in recurrent or metastatic SCCHN, and provided the rationale for the clinical phase II trial in pretreated SCCHN.. The primary end point was the progression-free survival rate (PFR) at 12 weeks. Forty eligible patients have been recruited after failure of platinum chemotherapy and cetuximab. A preplanned futility analysis was successfully passed after ≥1 success was detected in 20 patients. Secondary objectives consisted of progression-free survival (PFS), disease control rate (DCR), overall survival (OS), safety and tolerability, and predictive biomarkers for KRAS, BRAF, PIK3CA mutations, and HPV status. Archived tumor tissue was analyzed for DNA sequence.. A total of 40 patients were eligible. The PFR at 12 weeks was 40% (95% CI 25.0-54.6). The median PFS and OS were 56 days (95% CI 36-113 days) and 152 days (76-256 days), respectively. In 33 assessable patients, disease stabilization occurred in 57.6%, with tumor shrinkage in 13 patients (39.4%). Overall, the treatment was well tolerated. Fatigue (47.5%), anemia (25.0%), nausea (20.0%), and pneumonia (20.0%) were the most common adverse events. Neither PIK3CA mutations, nor HPV status were predictive for success with temsirolimus treatment. No mutations were found for KRAS or BRAF.. Tumor shrinkage and efficacy parameter indicate that inhibition of the PI3K-AKT-mTOR axis was a putative novel treatment paradigm for SCCHN. We could not identify parameters predictive for treatment success of temsirolimus, which underscores the need for refinement of the molecular analysis in future studies.. NCT01172769.

Topics: Adult; Aged; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Squamous Cell; Cetuximab; Cisplatin; Disease-Free Survival; Female; Germany; Head and Neck Neoplasms; Humans; Male; Middle Aged; Neoplasm Recurrence, Local; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Treatment Outcome

Squamous cell cancer of the head and neck (SCCHN) is a frequent aggressive malignancy with limited therapeutic options. Increasing evidence suggests that mammalian target of rapamycin (mTOR)-inhibitors might be effective in advanced SCCHN. However, non-invasive biomarkers for early prediction of treatment efficacy are not established in SCCHN. Highly proliferating tumours are characterised by enhanced cell turnover which is associated with enhanced apoptosis. During apoptosis of epithelial cells caspases cleave cytokeratin (CK)-18 can be detected in the blood. In this study we analysed sera from patients with relapsed or metastatic SCCHN patients who have been treated with temsirolimus for caspase-cleaved and total (caspase-cleaved and uncleaved) CK-18 by enzyme-linked immunosorbent assays (ELISAs). In addition, caspase-3 activity was detected by luminometric substrate assay. SCCHN patients revealed higher serum levels of those biomarkers compared to healthy controls. Importantly, patients with short progression-free survival (PFS) showed higher serum levels of caspase-3 activity compared to patients with longer PFS (⩾ 2months). Caspase-3 activity is inversely correlated with PFS. A cut-off value for caspase-3 activity was determined that correctly predicted PFS <2months with a sensitivity of 86% and a specificity of 67%. These data demonstrate that detection of serum caspase-3 activity might be a useful non-invasive biomarker for early identification of SCCHN patients not responding to treatment with novel targeted therapies such as mTOR-inhibitors.

Topics: Aged; Antineoplastic Agents; Biomarkers, Tumor; Carcinoma, Squamous Cell; Caspases; Disease-Free Survival; Enzyme-Linked Immunosorbent Assay; Female; Head and Neck Neoplasms; Humans; Male; Middle Aged; Predictive Value of Tests; Protein Kinase Inhibitors; Sirolimus; Squamous Cell Carcinoma of Head and Neck

The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of rapamycin (PI3K-AKT-mTOR) signalling pathway is aberrantly activated in several cancers. Notch signalling maintains cell proliferation, growth and metabolism in part by driving the PI3K pathway. Combining the mTOR inhibitor ridaforolimus with the Notch inhibitor MK-0752 may increase blockade of the PI3K pathway.. This phase I dose-escalation study (NCT01295632) aimed to define the dose-limiting toxicities (DLTs) and maximum tolerated dose (MTD) of combination oral ridaforolimus (rising doses starting at 20 mg, 5 days/week) and oral MK-0752 (1800 mg once weekly) in patients with solid tumours. No intrapatient dose escalation was permitted.. Twenty eight patients were treated on study. Ridaforolimus doses were escalated from 20 to 30 mg/day. Among 14 evaluable patients receiving ridaforolimus 20 mg, one DLT (grade 2 stomatitis, second episode) was reported. Among eight evaluable patients receiving ridaforolimus 30 mg, three DLTs were reported (one each grade 3 stomatitis, grade 3 diarrhoea, and grade 3 asthenia). The MTD was 20 mg daily ridaforolimus 5 days/week+1800 mg weekly MK-0752. The most common drug-related adverse events included stomatitis, diarrhoea, decreased appetite, hyperglycaemia, thrombocytopenia, asthenia and rash. Two of 15 (13%) patients with head and neck squamous cell carcinoma (HNSCC) had responses: one with complete response and one with partial response. In addition, one patient experienced stable disease ⩾6 months.. Combined ridaforolimus and MK-0752 showed activity in HNSCC. However, a high number of adverse events were reported at the MTD, which would require careful management during future clinical development.

Topics: Administration, Oral; Adult; Aged; Aged, 80 and over; Antineoplastic Combined Chemotherapy Protocols; Benzene Derivatives; Carcinoma, Squamous Cell; Drug Administration Schedule; Europe; Female; Head and Neck Neoplasms; Humans; Male; Maximum Tolerated Dose; Middle Aged; Molecular Targeted Therapy; Multimodal Imaging; Positron-Emission Tomography; Propionates; Protein Kinase Inhibitors; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Sulfones; Time Factors; Tomography, X-Ray Computed; Treatment Outcome; United States

Platinum-based therapy combined with cetuximab is standard first-line therapy for recurrent or metastatic squamous cell carcinoma of the head and neck (RMSCCHN). Preclinical studies have suggested that mammalian target of rapamycin inhibitors may overcome resistance to epidermal growth factor receptor blockers and may augment cetuximab antitumor activity. We conducted a phase 1b trial of carboplatin, cetuximab, and everolimus for untreated RMSCCHN.. Patients received carboplatin (area under the curve = 2 mg/ml/min; 3 weeks on, 1 week off), cetuximab (with a loading dose of 400 mg/m(2) and then 250 mg/m(2) weekly), and dose-escalating everolimus (2.5, 5.0, 7.5, and 10 mg/day) with a 3+3 design. After 4 cycles, patients without progression continued cetuximab/everolimus until progression or intolerable toxicity. Patients (age ≥ 18 years) had previously untreated, unresectable RMSCCHN not amenable to radiotherapy and an Eastern Cooperative Oncology Group performance status of 0 to 2.. The study enrolled 20 patients (male/female = 18/2) with RMSCCHN; the median age was 65 years (44-75 years). Thirteen patients received everolimus (male/female = 92%). Two of 6 patients receiving 2.5 mg/day experienced dose-limiting toxicity (DLT) with grade 3 hyponatremia and nausea. In 7 patients receiving de-escalated everolimus (2.5 mg every other day), grade 3 hyperglycemia produced DLT in 1 of 6 patients. The objective response rate (RR) was 61.5% (all partial responses). Progression-free survival (PFS) was 8.15 months. The pharmacokinetics of everolimus was described with a 2-compartment mixed-effects model. There was a significant correlation between tumor p-p44/42 staining and response (P = .044) and a marginally significant correlation between phosphorylated mammalian target of rapamycin and overall survival.. The maximum tolerated dose of everolimus with cetuximab and carboplatin was 2.5 mg every other day. The regimen was associated with an encouraging RR and PFS, and this suggested possible clinical efficacy in a select group of patients with squamous cell carcinoma of the head and neck.

Topics: Adult; Aged; Antibodies, Monoclonal, Humanized; Antineoplastic Combined Chemotherapy Protocols; Carboplatin; Carcinoma, Squamous Cell; Cetuximab; Disease-Free Survival; Drug Administration Schedule; Everolimus; Female; Head and Neck Neoplasms; Humans; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Metastasis; Recurrence; Sirolimus; Squamous Cell Carcinoma of Head and Neck

Elevated expression of eukaryotic protein synthesis initiation factor 4E (eIF4E) in histologically cancer-free margins of resected head and neck squamous cell carcinomas (HNSCCs) is mediated by mammalian target of rapamycin complex 1 (mTORC1) and has been associated with increased risk of disease recurrence. Preclinically, inhibition of mTORC1 with everolimus sensitizes cancer cells to cisplatin and radiation.. This was single-institution phase 1 study to establish the maximum tolerated dose of daily everolimus given with fixed dose cisplatin (30 mg/m(2) weekly × 6) and concurrent intensity modulated radiation therapy for patients with locally and/or regionally advanced head-and-neck cancer. The study had a standard 3 + 3 dose-escalation design.. Tumor primary sites were oral cavity (4), salivary gland (4), oropharynx (2), nasopharynx (1), scalp (1), and neck node with occult primary (1). In 4 of 4 cases in which resected HNSCC surgical pathology specimens were available for immunohistochemistry, elevated expression of eIF4E was observed in the cancer-free margins. The most common grade ≥3 treatment-related adverse event was lymphopenia (92%), and dose-limiting toxicities (DLTs) were mucositis (n=2) and failure to thrive (n=1). With a median follow up of 19.4 months, 2 patients have experienced recurrent disease. The maximum tolerated dose was everolimus 5 mg/day.. Head-and-neck cancer patients tolerated everolimus at therapeutic doses (5 mg/day) given with weekly cisplatin and intensity modulated radiation therapy. The regimen merits further evaluation, especially among patients who are status post resection of HNSCCs that harbor mTORC1-mediated activation of eIF4E in histologically negative surgical margins.

Topics: Administration, Oral; Adult; Aged; Antineoplastic Agents; Carcinoma, Squamous Cell; Chemoradiotherapy; Cisplatin; Drug Administration Schedule; Eukaryotic Initiation Factor-4E; Everolimus; Female; Head and Neck Neoplasms; Humans; Injections, Intravenous; Male; Maximum Tolerated Dose; Middle Aged; Neoplasm Proteins; Prospective Studies; Radiation-Sensitizing Agents; Radiotherapy Dosage; Radiotherapy, Intensity-Modulated; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases

Emerging evidence suggests that the modest response of head and neck squamous cell carcinoma (HNSCC) to treatment is associated with cancer stem cells (CSC). However, the signaling pathways that play a role in HNSCC CSC maintenance and therapy response are not well-understood. In this study, we investigate the response of CSCs to phosphatase and tensin homolog (PTEN) modulation and its potential dependency on the mammalian target of rapamycin (mTOR) signaling.. PTEN deficiency was stably induced using short hairpin RNA (shRNA). Downregulation of RPTOR/mTORC1 and RICTOR/mTORC2 was achieved using small interfering RNA (siRNA). CSCs were evaluated through tumorsphere formation and were classified into various subtypes: parasphere, merosphere, and holosphere. We investigated the effect of rapamycin on CSC properties in both control and PTEN-deficient HNSCC cells.. PTEN deficiency led to an accumulation of CSCs and enhanced a favorable response to rapamycin treatment. The viability of HNSCC CSCs was dependent on mTOR signaling. Deficiencies in both mTORC1 and mTORC2 reduced the number of CSCs. However, CSCs with PTEN deficiency had a greater reliance on mTORC1 signaling. Interestingly, when considering CSC subtypes, a deficiency in mTORC2 led to an increased number of paraspheres in both the control and PTEN-deficient groups.. Loss of PTEN signaling increased the HNSCC CSC population, which can be targeted by rapamycin. However, the mTORC2 deficiency can induce a problematic selection of paraspheres CSCs subtype.

Topics: Head and Neck Neoplasms; Humans; Mechanistic Target of Rapamycin Complex 1; Mechanistic Target of Rapamycin Complex 2; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Stem Cells; TOR Serine-Threonine Kinases

TP53 is the most frequently mutated gene in head and neck squamous cell carcinoma (HNSCC). Patients with HPV-negative TP53 mutant HNSCC have the worst prognosis, necessitating additional agents for treatment. Since mutant p53 causes sustained activation of the PI3K/AKT/mTOR signaling pathway, we investigated the effect of rapalogs RAD001 and CCI-779 on HPV-negative mutTP53 HNSCC cell lines and xenografts. Rapalogs significantly reduced cell viability and colony formation. Interestingly, rapalogs-induced autophagy with no effect on apoptosis. Pretreatment with autophagy inhibitors, 3-methyladenine (3-MA) and ULK-101 rescued the cell viability by inhibiting rapalog-induced autophagy, suggesting that both RAD001 and CCI-779 induce non-apoptotic autophagy-dependent cell death (ADCD). Moreover, rapalogs upregulated the levels of ULK1 and pULK1 S555 with concomitant downregulation of the mTORC1 pathway. However, pretreatment of cells with rapalogs prevented the ULK-101-mediated inhibition of ULK1 to sustained autophagy, suggesting that rapalogs induce ADCD through the activation of ULK1. To further translate our in vitro studies, we investigated the effect of RAD001 in HPV-negative mutTP53 (HN31 and FaDu) tumor cell xenograft model in nude mice. Mice treated with RAD001 exhibited a significant tumor volume reduction without induction of apoptosis, and with a concomitant increase in autophagy. Further, treatment with RAD001 was associated with a considerable increase in pULK1 S555 and ULK1 levels through the inhibition of mTORC1. 3-MA reversed the effect of RAD001 on FaDu tumor growth suggesting that RAD001 promotes ACDC in HPV-negative mutTP53 xenograft. This is the first report demonstrating that rapalogs promote non-apoptotic ADCD in HPV-negative mutTP53 HNSCC via the ULK1 pathway. Further studies are required to establish the promising role of rapalogs in preventing the regrowth of HPV-negative mutTP53 HNSCC.

Topics: Animals; Autophagic Cell Death; Autophagy-Related Protein-1 Homolog; Cell Line, Tumor; Cell Proliferation; Cell Survival; Everolimus; Gene Expression Regulation, Neoplastic; Head and Neck Neoplasms; Humans; Intracellular Signaling Peptides and Proteins; Mice; MTOR Inhibitors; Mutation; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Tumor Suppressor Protein p53; Xenograft Model Antitumor Assays

The phosphatidylinositol 3-kinase/protein kinase-B/mammalian target of the rapamycin (PI3K-AKT-mTOR) signaling pathway is an important regulator of cell proliferation, survival, and motility. The gain or loss of function of proteins related to this pathway results in the neoplastic transformation in several types of cancers. This study aimed to evaluate the expression profile of the PI3K-AKT-mTOR pathway in patients with head and neck squamous cell carcinoma (HNSCC) and HNSCC cell lines.. The study involved 26 formalin-fixed paraffin-embedded tissue samples from patients with HNSCC. The analysis of immunohistochemical expression of PI3K, AKT, p-mTOR, and phosphatase and tensin homolog (PTEN) proteins was performed by a quantitative assessment. The in vitro gene and protein expression evaluation was performed by real-time polymerase chain reaction and Western blot assay, respectively, in the human cell lines SCC-9 and FaDu.. High levels of PI3K, AKT, and p-mTOR were found in most HNSCC tumors. Following this result, we observed low amounts or absence of PTEN in most samples. Additionally, the FaDu cells (pharynx) showed higher AKT expression but lower expression of p-mTOR compared with SCC-9 cells (oral cavity), which hints at a loco-anatomical relevance.. Overall, this study found increased expression of the PI3K-AKT-mTOR pathway along with evident PTEN reduction in head and neck cancer.

Topics: Brazil; Cell Line, Tumor; Cell Proliferation; Head and Neck Neoplasms; Humans; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; PTEN Phosphohydrolase; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases

EGFR inhibitors have shown poor efficacy in head and neck squamous cell carcinoma (HNSCC) with demonstrated involvement of the insulin-like growth factor-1 receptor (IGF1R) in resistance to EGFR inhibition. IGF1R activates the PI3K-Akt pathway, which phosphorylates proline-rich Akt substrate of 40 kDa (PRAS40) to cease mTOR inhibition resulting in increased mTOR signaling. Proliferation assays separated six HNSCC cell lines into two groups: sensitive to EGFR inhibition or resistant; all sensitive cell lines demonstrated reduced sensitivity to EGFR inhibition upon IGF1R activation. Reverse phase protein microarray analysis and immunoblot identified a correlation between increased PRAS40 phosphorylation and IGFR-mediated resistance to EGFR inhibition. In sensitive cell lines, PRAS40 phosphorylation decreased 44%-80% with EGFR inhibition and was restored to 98%-196% of control by IGF1R activation, while phosphorylation was unaffected in resistant cell lines. Possible involvement of mTOR in this resistance mechanism was demonstrated through a similar pattern of p70S6K phosphorylation. However, addition of temsirolimus, an mTORC1 inhibitor, was insufficient to overcome IGF1R-mediated resistance and suggested an alternative mechanism. Forkhead box O3a (FOXO3a), which has been reported to complex with PRAS40 in the cytoplasm, demonstrated a 6-fold increase in nuclear to cytoplasmic ratio upon EGFR inhibition that was eliminated with concurrent IGF1R activation. Transcription of FOXO3a-regulated TRAIL and PTEN-induced putative kinase-1 (PINK1) was increased with EGFR inhibition in sensitive cell lines; this effect was diminished with IGF1R stimulation. IMPLICATIONS: These data suggest PRAS40 may play an important role in IGF1R-based therapeutic resistance to EGFR inhibition, and this likely occurs via inhibition of FOXO3a-mediated proapoptotic gene transcription.

Topics: Adaptor Proteins, Signal Transducing; Cell Line, Tumor; Drug Resistance, Neoplasm; ErbB Receptors; Head and Neck Neoplasms; Humans; Insulin-Like Growth Factor I; Mechanistic Target of Rapamycin Complex 1; Phosphorylation; Protein Kinase Inhibitors; Receptor, IGF Type 1; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases

Programmed death‑ligand 1 (PD‑L1), an immune co‑stimulatory molecule, is expressed on various cancer cells and the surface of immune cells. Its overexpression on tumor cells suppresses the immune response to promote tumor cell immune escape. The present study demonstrated that PD‑L1 was critical in head and neck squamous cell carcinoma (HNSCC) carcinogenesis. Immunohistochemical analysis of HNSCC tissue microarrays revealed that PD‑L1 was overexpressed in tumor tissue, and its expression increased as tumor malignancy progressed (from grade I to IV). Subsequently, the expression of PD‑L1 was knocked down or overexpressed in the HNSCC cell lines Cal‑27 and Fadu. It was demonstrated that PD‑L1 significantly induced HNSCC cell proliferation and colony forming ability. Cell proliferation was also promoted in Cal‑27 cell xenograft BALB/c nude mice. In addition, it was determined by western blotting that the PD‑L1‑mediated increase in HNSCC cell proliferation may have been associated with the activation of mammalian target of rapamycin (mTOR) signaling pathway. Furthermore, mTOR inhibitor (rapamycin) prevented the increase in proliferation. Based on these results, it was concluded that PD‑L1 promoted cell proliferation of HNSCC cells through mTOR signaling, and blocking PD‑L1 may be conducive in HNSCC therapy.

Topics: Adult; Aged; Animals; Apoptosis; B7-H1 Antigen; Cell Line, Tumor; Cell Proliferation; Female; Head and Neck Neoplasms; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Middle Aged; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Tissue Array Analysis; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

CIP2A may activate multiple oncogenic proteins and promote the proliferation of various cancer cells.. We investigated that the role of CIP2A in radioresistant head and neck cancer (HNC) cell line with TP53 mutation and the effect of the rapamycin on the response of HN31 with TP53 mutation cells to irradiation related to CIP2A expression.. CIP2A expression was stimulated by p53 mutation and critical for the inhibition of senescence induction in response to radiation. The treatment with radiation alone neither induced cytotoxicity in HN31 cells nor completely suppressed the activation of CIP2A. However, the combination of radiation and rapamycin increase the radiosensitivity through the induction of senescence with downregulation of CIP2A expression both in vivo and in vitro.. Our results suggest that CIP2A may serve as a therapeutic target of rapamycin through induction of senescence in radioresistant HNC with TP53 mutation.

Topics: Animals; Antibiotics, Antineoplastic; Autoantigens; Cell Culture Techniques; Cell Line, Tumor; Head and Neck Neoplasms; Humans; Intracellular Signaling Peptides and Proteins; Male; Membrane Proteins; Mice; Mutation; Neoplasm Transplantation; Radiation Tolerance; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Tumor Suppressor Protein p53

Head and neck squamous cell carcinoma (HNSCC) clearly involves activation of the Akt mammalian target of rapamycin (mTOR) signalling pathway. However, the effectiveness of treatment with the mTOR inhibitor rapamycin is often limited by chemoresistance. Melatonin suppresses neoplastic growth via different mechanisms in a variety of tumours. In this study, we aimed to elucidate the effects of melatonin on rapamycin-induced HNSCC cell death and to identify potential cross-talk pathways. We analysed the dose-dependent effects of melatonin in rapamycin-treated HNSCC cell lines (Cal-27 and SCC-9). These cells were treated with 0.1, 0.5 or 1 mmol/L melatonin combined with 20 nM rapamycin. We further examined the potential synergistic effects of melatonin with rapamycin in Cal-27 xenograft mice. Relationships between inhibition of the mTOR pathway, reactive oxygen species (ROS), and apoptosis and mitophagy reportedly increased the cytotoxic effects of rapamycin in HNSCC. Our results demonstrated that combined treatment with rapamycin and melatonin blocked the negative feedback loop from the specific downstream effector of mTOR activation S6K1 to Akt signalling, which decreased cell viability, proliferation and clonogenic capacity. Interestingly, combined treatment with rapamycin and melatonin-induced changes in mitochondrial function, which were associated with increased ROS production, increasing apoptosis and mitophagy. This led to increase cell death and cellular differentiation. Our data further indicated that melatonin administration reduced rapamycin-associated toxicity to healthy cells. Overall, our findings suggested that melatonin could be used as an adjuvant agent with rapamycin, improving effectiveness while minimizing its side effects.

Topics: Animals; Antineoplastic Combined Chemotherapy Protocols; Apoptosis; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cell Survival; Head and Neck Neoplasms; Humans; Melatonin; Mice; Mice, Nude; Mitophagy; Proto-Oncogene Proteins c-akt; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Aberrant epidermal growth factor receptor (EGFR) signaling is associated with tumor growth in head and neck squamous cell carcinoma (HNSCC) and is a major focus of targeted therapy. The phosphatidylinositol-3-kinase/AKT/mammalian target of the rapamycin (PI3K/AKT/mTOR) signaling pathway is frequently mutated in HNSCC and is involved in disease progression and resistance to EGFR inhibitors. The aim of this study was to assess the antiproliferative effects of mTOR inhibition (temsirolimus) combined with the anti-EGFR monoclonal antibody cetuximab, administered according to different combination schedules. Antiproliferative effects of the combination of temsirolimus and cetuximab were determined on the representative HNSCC CAL33 cell line (PI3KCA H1047R mutated and K-RAS wild-type). In addition, key proteins related to the EGFR pathway (pEGFR/EGFR, pAKT/AKT) and the mTOR pathway (p-p70S6K1, p4E-BP1) were determined to explain the cytotoxic effects. Temsirolimus and cetuximab showed a synergistic effect when administered in combination. Supra-additive effect was lost when the two drugs were administered sequentially, irrespective of which drug was administered first. Synergistic effect of the combination was corroborated by a marked downregulation of pEGFR, significant downregulation of pAKT expression, and a marked diminution of p70S6K1 and p4E-BP1 expression. Our study demonstrated a synergistic effect of temsirolimus and cetuximab administered in combination, well illustrated by a simultaneous blockade of intracellular signaling pathways regulating cell proliferation and survival. These results establish the notion of a schedule dependency for the combined treatment, which can be of importance at the clinical level.

Topics: Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Squamous Cell; Cell Line, Tumor; Cetuximab; Drug Administration Schedule; Drug Interactions; Drug Synergism; ErbB Receptors; Head and Neck Neoplasms; Humans; Mechanistic Target of Rapamycin Complex 1; Proto-Oncogene Proteins c-akt; ras Proteins; Sirolimus; Squamous Cell Carcinoma of Head and Neck

Head and neck squamous cell carcinoma (HNSCC) is an aggressive epithelial malignancy. It is the most common neoplasm appearing in the upper aerodigestive tract and the sixth most common cancer worldwide. The five-year survival rate remains poor despite advances in surgery, radiation and chemotherapy. Furthermore, the incidence of human papillomavirus (HPV)-associated oropharyngeal cancer is rising. Thus, innovative therapy approaches are imperative in order to improve the situation. Everolimus, an inhibitor of the mammalian target of rapamycin (mTOR) and sorafenib and sunitinib, multityrosine kinase inhibitors, have been notably effective in the therapy of different tumor entities. The modest side-effects and oral application of the drugs might improve patient compliance. Expression levels of mTOR and Amphiregulin (AREG) in p16-positive and -negative SCC (squamous cell carcinoma) and the effect of everolimus, sorafenib or sunitinib on the expression levels of these target proteins were assessed. As far as we are aware of, this is one of the first in vitro studies to evaluate the effect of these small-molecule drugs with regard to the p16 status of SCC cells.. p16-negative HNSCC 11A and 14C cells and p16-positive CERV196 cells were exposed to different concentrations of everolimus, sorafenib and sunitinib for 2-8 days. Expression levels of mTOR and AREG were determined by enzyme-linked immunosorbent assay (ELISA) and compared against a chemonaïve control.. AREG and mTOR were expressed in all tested cell lines. CERV196 displayed a remarkable increase of mTOR expression compared to p16-negative HNSCC. On the contrary, AREG levels were reduced by 50% in CERV196. Everolimus, sorafenib and sunitinib significantly reduced mTOR expression. Everolimus significantly decreased AREG expression independently of the HPV status. Sunitinib and sorafenib increased AREG expression in HNSCC 11A and 14C but not in CERV196.. The applied drugs showed remarkable suppression of mTOR expression, which might delay tumor progression. Interestingly, sorafenib and sunitinib increased AREG in HNSCC 11A and 14C, which could be a possible evasive mechanism following incubation with these drugs. On the contrary, p16-positive CERV196 showed increased susceptibility to sorafenib and sunitinib concerning suppression of AREG expression. Further studies are required to evaluate the HPV-dependent differences of therapy response and the possible consequences for treatment options.

Topics: Amphiregulin; Carcinoma, Squamous Cell; EGF Family of Proteins; Everolimus; Gene Expression Regulation, Neoplastic; Head and Neck Neoplasms; Human papillomavirus 16; Humans; Indoles; Molecular Targeted Therapy; Niacinamide; Papillomaviridae; Phenylurea Compounds; Pyrroles; Sirolimus; Sorafenib; Squamous Cell Carcinoma of Head and Neck; Sunitinib; TOR Serine-Threonine Kinases

The mammalian target of rapamycin (mTOR) signaling pathway plays a pivotal role in numerous cellular processes involving growth, proliferation and survival. The purpose of this study was to investigate the anti-tumoral effect of the mTOR inhibitor (mTORi) CCI-779 in HNSCC cell lines and its potency in cisplatin- and cetuximab-resistant cells.. A panel of 10 HNSCC cell lines with differences in TP53 mutational status and basal cisplatin sensitivity and two isogenic models of acquired resistance to cisplatin and cetuximab, respectively were studied. Cell survival after treatment with CCI-779, cisplatin and cetuximab alone or in combination was determined by MTT assays. Potential predictive biomarkers for tumor cell sensitivity to CCI-779 were evaluated.. We observed considerable heterogeneity in sensitivity of HNSCC cell lines to CCI-779 monotherapy. Sensitivity was observed in TP53 mutated as well as wild-type cell lines. Total and p-EGFR expression levels but not the basal activity of the mTOR and MAPK signaling pathways were correlated with sensitivity to CCI-779. Resistant cells with increased EGFR activation could be sensitized by the combination of CCI-779 with cetuximab. Interestingly, cell lines with acquired resistance to cisplatin displayed a higher sensitivity to CCI-779 whereas cetuximab-resistant cells were less sensitive to the drug, but could be sensitized to CCI-779 by EGFR blockade.. Activity of CCI-779 in HNSCC cells harboring TP53 mutations and displaying a phenotype of cisplatin resistance suggests its clinical potential even in patients with dismal outcome after current standard treatment. Cetuximab/mTORi combinations might be useful for treatment of tumors with high expression of EGFR/p-EGFR and/or acquired cetuximab resistance. This combinatorial treatment modality needs further evaluation in future translational and clinical studies.

Topics: Antineoplastic Agents; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cell Survival; Cetuximab; Cisplatin; Drug Resistance, Neoplasm; ErbB Receptors; Head and Neck Neoplasms; Humans; Mutation; RNA, Messenger; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases

Radiotherapy is widely used to treat cancer because it has the advantage of physically and functionally conserving the affected organ. To improve radiotherapy and investigate the molecular mechanisms of cellular radioresistance, we established a clinically relevant radioresistant (CRR) cell line, SAS-R, from SAS cells. SAS-R cells continue to proliferate when exposed to fractionated radiation (FR) of 2 Gy/day for more than 30 days in vitro. A xenograft tumor model of SAS-R was also resistant to 2 Gy/day of X-rays for 30 days. The density of blood vessels in SAS-R tumors was higher than in SAS tumors. Everolimus, a mammalian target of rapamycin (mTOR) inhibitor, sensitized microvascular endothelial cells to radiation, but failed to radiosensitize SAS and SAS-R cells in vitro. Everolimus with FR markedly reduced SAS and SAS-R tumor volumes. Additionally, the apoptosis of endothelial cells (ECs) increased in SAS-R tumor tissues when both Everolimus and radiation were administered. Both CD34-positive and tomato lectin-positive blood vessel densities in SAS-R tumor tissues decreased remarkably after the Everolimus and radiation treatment. Everolimus-induced apoptosis of vascular ECs in response to radiation was also followed by thrombus formation that leads to tumor necrosis. We conclude that FR combined with Everolimus may be an effective modality to overcome radioresistant tumors via targeting tumor ECs.

Topics: Animals; Antineoplastic Agents; Apoptosis; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Endothelial Cells; Everolimus; Female; Head and Neck Neoplasms; HeLa Cells; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Radiation-Sensitizing Agents; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Uterine Cervical Neoplasms; Xenograft Model Antitumor Assays

Human papillomavirus (HPV)-related head and neck squamous cell carcinoma (HNSCC) incidence is increasing at a near epidemic rate. We investigated whether the mammalian (or mechanistic) target of rapamycin (mTOR) inhibitor, rapamycin, can be used as a concurrent agent to standard-of-care cisplatin/radiation therapy (CRT) to attenuate tumor lactate production, thus enhancing CRT-induced immune-mediated clearance of this antigenic tumor type. A C57Bl/6-derived mouse oropharyngeal epithelial cell line retrovirally transduced with HPV type 16 E6/E7 and human squamous cell carcinoma cell lines were evaluated for their response to rapamycin in vitro with proliferation assays, Western blots, and lactate assays. Clonogenic assays and a preclinical mouse model were used to assess rapamycin as a concurrent agent to CRT. The potential of rapamycin to enhance immune response through lactate attenuation was assessed using quantitative tumor lactate bioluminescence and assessment of cell-mediated immunity using E6/E7-vaccinated mouse splenocytes. Rapamycin alone inhibited mTOR signaling of all cancer cell lines tested in vitro and in vivo. Furthermore, rapamycin administered alone significantly prolonged survival in vivo but did not result in any long-term cures. Given concurrently, CRT/rapamycin significantly enhanced direct cell killing in clonogenic assays and prolonged survival in immunocompromised mice. However, in immunocompetent mice, concurrent CRT/rapamycin increased long-term cures by 21%. Preliminary findings suggest that improved survival involves increased cell killing and enhanced immune-mediated clearance in part due to decreased lactate production. The results may provide rationale for the clinical evaluation of mTOR inhibitors concurrent with standard-of-care CRT for treatment of HPV-positive HNSCC.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cisplatin; Head and Neck Neoplasms; Human papillomavirus 16; Humans; Immunity, Cellular; Lactates; Male; Mice; Mice, Inbred C57BL; Papillomavirus Infections; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; Survival Rate; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Heat shock protein 90 (HSP90) and mammalian target of rapamycin (mTOR) are involved in the molecular pathogenesis of advanced oral squamous cell carcinoma. HSP90 inhibitors are capable of effectively interfering with multiple signaling pathways, including the mTOR signaling pathway. However, the combined effects of HSP90 and mTOR inhibitors on oral squamous cell carcinoma are still unknown. In this study, we investigated the dual treatment of the novel HSP90 inhibitor NVP-AUY922 and temsirolimus against oral squamous cell carcinoma.. The effect of the combination of NVP-AUY922 and temsirolimus on oral squamous cell carcinoma in vitro and in vivo was determined by MTS assay and mouse xenograft models. The effect of the combination on angiogenesis was determined by tube formation assay and angioreactor.. The combination treatment of NVP-AUY922 and temsirolimus significantly inhibited the proliferation of SAS oral squamous cell carcinoma cells in vitro and suppressed the growth of oral squamous cell carcinoma xenografts in vivo. We have clearly shown that the combination treatment of NVP-AUY922 and temsirolimus inhibited vascular formation both in vitro and in vivo. Moreover, the combination treatment of NVP-AUY922 and temsirolimus prolonged the survival rate in mice xenografted with oral squamous cell carcinoma.. Here, we showed the activity of a combination of mTOR and HSP90 inhibitors for the treatment of advanced oral squamous carcinoma.

Topics: Angiogenesis Inhibitors; Animals; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Squamous Cell; Cell Line, Tumor; Cells, Cultured; Female; Head and Neck Neoplasms; HSP90 Heat-Shock Proteins; Human Umbilical Vein Endothelial Cells; Humans; Isoxazoles; Mice; Mice, Nude; Molecular Targeted Therapy; Mouth Neoplasms; Neoplasm Proteins; Neovascularization, Pathologic; Protein Kinase Inhibitors; Random Allocation; Resorcinols; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Xenograft Model Antitumor Assays

Rapamycin is an mTOR inhibitor with preclinical efficacy in squamous cell carcinoma of the head and neck (SCCHN). However, mTOR inhibitors also increase Akt activity in SCCHN cell lines, which would promote survival and oncogenesis. Enzastaurin is an AGC kinase inhibitor with nanomolar inhibitory concentrations for Akt and protein kinase C (PKC). Moreover, Akt and PKC inhibitors have demonstrated efficacy in SCCHN.. We hypothesized that the combination of rapamycin and enzastaurin would be more effective than either agent alone.. Rapamycin and enzastaurin generally inhibited putative targets in SCCHN cell lines in culture. In mice xenografted with CAL27 cells, rapamycin and enzastaurin produced growth delay. In contrast, the combination of rapamycin and enzastaurin caused regression of CAL27 tumors with evidence of inhibition of putative targets, survival, angiogenesis and proliferation.. These data demonstrate that the combination of rapamycin and enzastaurin disrupts critical oncogenic pathways in SCCHN and has efficacy in preclinical models.

Topics: Animals; Antibiotics, Antineoplastic; Apoptosis; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Proliferation; Cell Survival; Drug Synergism; Female; Head and Neck Neoplasms; In Situ Nick-End Labeling; Indoles; MAP Kinase Signaling System; Mice; Mice, Nude; Neoplasm Transplantation; Neovascularization, Pathologic; Protein Kinase Inhibitors; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Tumor Cells, Cultured

Recently it has been shown that radiation induces migration of glioma cells and facilitates a further spread of tumor cells locally and systemically. The aim of this study was to evaluate whether radiotherapy induces migration in head and neck squamous cell carcinoma (HNSCC). A further aim was to investigate the effects of blocking the epidermal growth factor receptor (EGFR) and its downstream pathways (Raf/MEK/ERK, PI3K/Akt) on tumor cell migration in vitro.. Migration of tumor cells was assessed via a wound healing assay and proliferation by a MTT colorimeritric assay using 3 HNSCC cell lines (BHY, CAL-27, HN). The cells were treated with increasing doses of irradiation (2 Gy, 5 Gy, 8 Gy) in the presence or absence of EGF, EGFR-antagonist (AG1478) or inhibitors of the downstream pathways PI3K (LY294002), mTOR (rapamycin) and MEK1 (PD98059). Biochemical activation of EGFR and the downstream markers Akt and ERK were examined by Western blot analysis.. In absence of stimulation or inhibition, increasing doses of irradiation induced a dose-dependent enhancement of migrating cells (p < 0.05 for the 3 HNSCC cell lines) and a decrease of cell proliferation (p < 0.05 for the 3 HNSCC cell lines). The inhibition of EGFR or the downstream pathways reduced cell migration significantly (almost all p < 0.05 for the 3 HNSCC cell lines). Stimulation of HNSCC cells with EGF caused a significant increase in migration (p < 0.05 for the 3 HNSCC cell lines). After irradiation alone a pronounced activation of EGFR was observed by Western blot analysis.. Our results demonstrate that the EGFR is involved in radiation induced migration of HNSCC cells. Therefore EGFR or the downstream pathways might be a target for the treatment of HNSCC to improve the efficacy of radiotherapy.

Topics: Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Movement; Dose-Response Relationship, Radiation; Epidermal Growth Factor; ErbB Receptors; Flavonoids; Gamma Rays; Head and Neck Neoplasms; Humans; MAP Kinase Kinase 1; MAP Kinase Signaling System; Phosphatidylinositol 3-Kinases; Quinazolines; Signal Transduction; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Tyrphostins

Despite our improved understanding of cancer, the 5-year survival rate for head and neck squamous cell carcinomas (HNSCC) patients remains relatively unchanged at 50% for the past three decades. HNSCCs often metastasize to locoregional lymph nodes, and lymph node involvement represents one of the most important prognostic factors of poor clinical outcome. Among the multiple dysregulated molecular mechanism in HNSCCs, emerging basic, preclinical, and clinical findings support the importance of the mTOR signaling route in HNSCC progression. Indeed, we observed here that the activation of mTOR is a widespread event in clinical specimens of HNSCCs invading locoregional lymph nodes. We developed an orthotopic model of HNSCC consisting of the implantation of HNSCC cells into the tongues of immunocompromised mice. These orthotopic tumors spontaneously metastasize to the cervical lymph nodes, where the presence of HNSCC cells can be revealed by histologic and immunohistochemical evaluation. Both primary and metastatic experimental HNSCC lesions exhibited elevated mTOR activity. The ability to monitor and quantitate lymph node invasion in this model system enabled us to explore whether the blockade of mTOR could impact HNSCC metastasis. We found that inhibition of mTOR with rapamycin and the rapalog RAD001 diminished lymphangiogenesis in the primary tumors and prevented the dissemination of HNSCC cancer cells to the cervical lymph nodes, thereby prolonging animal survival. These findings may provide a rationale for the future clinical evaluation of mTOR inhibitors, including rapamycin and its analogues, as part of a molecular-targeted metastasis preventive strategy for the treatment of patients with HNSCC.

Topics: Animals; Carcinoma, Squamous Cell; Everolimus; Female; Head and Neck Neoplasms; Humans; Lymphangiogenesis; Lymphatic Metastasis; Mice; Mice, SCID; Sirolimus; Squamous Cell Carcinoma of Head and Neck; TOR Serine-Threonine Kinases; Transcription Factors