The current role of systemic chemotherapy in the primary treatment of head and neck cancer

Inhibition of autophagy initiation: A novel strategy for oral squamous cell carcinomas

BACKGROUND

Oral squamous cell carcinoma (OSCC) is one of the most common forms of oral cancer and is known to have poor prognostic outcomes. Autophagy is known to be associated with aggressive tumor biology of OSCC. Hence, this study aimed to develop a novel therapeutic strategy against OSCC by targeting the autophagic pathway.

METHODS

Immunoblotting, and confocal microscopy were used to examine the effect of tumor microenvironmental stressors on the autophagy activity. Cellular proliferation and migration assays were performed to assess the anti-cancer activity of standard chemotherapy and autophagy initiation inhibitors, either alone or in combination. High resolution mass-spectrometry based proteomic analysis was utilized to understand the mechanisms behind chemoresistance in OSCC models. Finally, immunohistochemistry was performed to determine associations between autophagy markers and clinicopathological characteristics.

RESULTS

Tumor microenvironmental stressors were shown to induce autophagy activity in OSCC cell lines. Novel combinations of chemotherapy and autophagy inhibitors as well as different classes of autophagy inhibitors were identified. Combination of MRT68921 and SAR405 demonstrated marked synergy in their anti-proliferative activity and also showed synergy with chemotherapy in chemoresistant OSCC cell models. Autophagy was identified as one of the key pathways involved in mediating chemoresistance in OSCC. Furthermore, TGM2 was identified as a key upstream regulator of chemoresistance in OSCC models. Finally, positive staining for autophagosome marker LC3 was shown to be associated with low histological grade OSCC.

CONCLUSION

In conclusion, this study identified a combination of novel autophagy inhibitors which can potently inhibit proliferation of both chemosensitive as well as chemoresistant OSCC cells and could be developed as a novel therapy against advanced OSCC tumors.

Enhancing the anticancer potential of metformin: fabrication of efficient nanospanlastics, in vitro cytotoxic studies on HEP-2 cells and reactome enhanced pathway analysis

Metformin (MET), an oral antidiabetic drug, was reported to possess promising anticancer effects. We hypothesized that MET encapsulation in unique nanospanlastics would enhance its anticancer potential against HEP-2 cells. Our results showed the successful fabrication of Nano-MET spanlastics (d = 232.10 ± 0.20 nm; PDI = 0.25 ± 0.11; zeta potential = (-) 44.50 ± 0.96; drug content = 99.90 ± 0.11 and entrapment efficiency = 88.01 ± 2.50%). MTT assay revealed the enhanced Nano-MET cytotoxicity over MET with a calculated IC50 of 50 μg/mL and > 500 μg/mL, respectively. Annexin V/PI apoptosis assay showed that Nano-MET significantly decreased the percentage of live cells from 95.49 to 93.70 compared to MET and increased the percentage of cells arrested in the G0/G1 phase by 8.38%. Moreover, Nano-MET downregulated BCL-2 and upregulated BAX protein levels by 1.57 and 1.88 folds, respectively. RT-qPCR revealed that Nano-MET caused a significant 13.75, 4.15, and 2.23-fold increase in caspase-3, -8, and - 9 levels as well as a 100 and 43.47-fold decrease in cyclin D1 and mTOR levels, respectively. The proliferation marker Ki67 immunofluorescent staining revealed a 3-fold decrease in positive cells in Nano-MET compared to the control. Utilizing the combined Pathway-Enrichment Analysis (PEA) and Reactome analysis indicated high enrichment of certain pathways including nucleotides metabolism, Nudix-type hydrolase enzymes, carbon dioxide hydration, hemostasis, and the innate immune system. In summary, our results confirm MET cytotoxicity enhancement by its encapsulation in nanospanlastics. We also highlight, using PEA, that MET can modulate multiple pathways implicated in carcinogenesis.

Emerging Role of Autophagy in the Development and Progression of Oral Squamous Cell Carcinoma

Autophagy is a cellular catabolic process, which is characterized by degradation of damaged proteins and organelles needed to supply the cell with essential nutrients. At basal levels, autophagy is important to maintain cellular homeostasis and development. It is also a stress responsive process that allows the cells to survive when subjected to stressful conditions such as nutrient deprivation. Autophagy has been implicated in many pathologies including cancer. It is well established that autophagy plays a dual role in different cancer types. There is emerging role of autophagy in oral squamous cell carcinoma (OSCC) development and progression. This review will focus on the role played by autophagy in relation to different aspects of cancer progression and discuss recent studies exploring the role of autophagy in OSCC. It will further discuss potential therapeutic approaches to target autophagy in OSCC.

Locally Advanced Oral Tongue Cancer: Is Organ Preservation a Safe Option in Resource-Limited High-Volume Setting?

Background

Oral tongue is found to be the most common intraoral subsite with worse prognosis despite the use of multimodality treatments. Extensive resections have resulted in loss of form and function of tongue in advanced tumors. The objective of the study was to analyze the role of induction chemotherapy (IC) in intermediate to advanced staged oral tongue cancer for organ preservation and survival outcome in a developing country.

Materials and Methods

The records of oral tongue cancer patients treated from 2007 to 2016 were retrospectively analyzed.

Results

Eighty-one oral tongue cancer patients with advanced stage were treated using induction arm in 10 years. The median follow-up was 24 months with 3- and 5-year survival of 77% and 58%, respectively. IC has an overall response in 87% of the patients at primary site. The chemotherapy has completely resolved the nodal disease in 17% of the patients, but 23% of the patients had failed to respond. Only 21% of the patients received reconstruction using local or regional flaps.

Conclusion

IC has shown encouraging results in advanced staged oral tongue cancers with function preservation and improved survival outcome in less privileged high-volume centers.

Autophagy modulators for the treatment of oral and esophageal squamous cell carcinomas

Oral squamous cell carcinomas (OSCC) and esophageal squamous cell carcinomas (ESCC) exhibit a survival rate of less than 60% and 40%, respectively. Late-stage diagnosis and lack of effective treatment strategies make both OSCC and ESCC a significant health burden. Autophagy, a lysosome-dependent catabolic process, involves the degradation of intracellular components to maintain cell homeostasis. Targeting autophagy has been highlighted as a feasible therapeutic strategy with clinical utility in cancer treatment, although its associated regulatory mechanisms remain elusive. The detection of relevant biomarkers in biological fluids has been anticipated to facilitate early diagnosis and/or prognosis for these tumors. In this context, recent studies have indicated the presence of specific proteins and small RNAs, detectable in circulating plasma and serum, as biomarkers. Interestingly, the interplay between biomarkers (eg, exosomal microRNAs) and autophagic processes could be exploited in the quest for targeted and more effective therapies for OSCC and ESCC. In this review, we give an overview of the available biomarkers and innovative targeted therapeutic strategies, including the application of autophagy modulators in OSCC and ESCC. Additionally, we provide a viewpoint on the state of the art and on future therapeutic perspectives combining the early detection of relevant biomarkers with drug discovery for the treatment of OSCC and ESCC.

Efficacy and Safety of Intro-Arterial Chemotherapy Combined with Radiotherapy on Head and Neck Cancer: A Systematic Review and Meta-Analysis

Objectives: Intro-arterial chemotherapy combined with radiotherapy (IACRT) for the treatment of head and neck cancer (HNC) underwent a revival in recent years. Although many clinical trials have reported favorable outcomes, the effect of IACRT for HNC is still controversial. Therefore, this study was designed to evaluate the efficacy and safety of IACRT for HNC.

Methods: The relevant articles published before August 2019 were searched from PubMed, Embase, Cochrane Library, Web of Science and PMC databases. Data were extracted and the combined complete response (CR), overall survival (OS) and toxicity incidence with 95% credible interval (CI) were examined from eligible studies.

Results: Thirty-four studies comprising 1890 patients were included. IACRT achieved high CR (0.81, 95% CI: 0.76-0.86, P < 0.001), 3-year OS (0.75, 95% CI: 0.68-0.82, P < 0.001) and 5-year OS (0.68, 95% CI: 0.61-0.75, P < 0.001). The 3-year OS rate of stage III cancer (0.75, 95% CI: 0.53-0.97, P< 0.001) was higher than stage IV (0.52, 95% CI: 0.37-0.66, P = 0.025). Meanwhile, the 5-year OS of T3 cancer (0.87, 95% CI: 0.73-1.01, P = 0.028) was higher than T4 (0.53, 95% CI: 0.42-0.63, P = 0.286). Additionally, oral diseases, mucositis, leukopenia and dermatitis were the major toxicities of IACRT, which were all reversible.

Conclusion: IACRT is an efficient and safe modality for HNC, which could achieve favorable cancer response and higher survival rate with acceptable toxicities, even for advanced HNC.

Role of chemotherapy in 5000 patients with head and neck cancer treated by curative surgery: A subgroup analysis of the meta-analysis of chemotherapy in head and neck cancer

OBJECTIVE

To evaluate the effect of chemotherapy added to a surgical locoregional treatment (LRT) for patients with locally advanced head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

We studied the sub-group of trials with surgical LRT included in the meta-analysis on chemotherapy in head and neck cancer (MACH-NC). Data from published and unpublished randomized trials comparing the addition of chemotherapy to LRT in HNSCC patients were sought using electronic database searching for the period 1965-2000, hand searching and by contacting experts in the field. Trials with less than 60 patients, or preoperative radiotherapy or where the type of LRT could not be individually determined were excluded. All individual patient data were checked for internal consistency, compared with published reports, and validated with trialists. Data were pooled using a fixed-effect model. Heterogeneity was assessed using Cochrane test and I² statistic.

RESULTS

Twenty-four trials were eligible (5000 patients). Chemotherapy improved overall survival (HR = 0.92 [95%CI: 0.85-0.99] p = 0.02). There was a significant interaction between treatment effect and timing of chemotherapy (p = 0.08 at pre-specified threshold of 0.10) with a greater effect for concomitant chemotherapy (HR = 0.79, 95%CI: 0.69-0.92). The benefit of chemotherapy was greater in women (HR_women = 0.63, 95%CI: 0.50-0.80) compared to men (HR_men = 0.96, 95%CI: 0.89-1.04; p for interaction = 0.001).

CONCLUSIONS

This analysis confirmed the benefit of concomitant chemotherapy added to surgical LRT. The role of induction therapy as yet to be determined as it did not improve OS. Women may benefit more than men from chemotherapy.

IRX-2 natural cytokine biologic for immunotherapy in patients with head and neck cancers

Head and neck squamous cell carcinoma (HNSCC) is an immunosuppressive malignancy characterized by tumor-driven immune-system abnormalities that contribute to disease progression. For patients with surgically resectable HNSCC, treatment is often curative surgery followed by irradiation or chemoradiation in high-risk settings to reduce the risk of recurrence. Poor survival and considerable morbidity of current treatments suggest the need for new therapeutic modalities that can improve outcomes. Defects in antitumor immunity of HNSCC patients include suppressed dendritic cell (DC) maturation, deficient antigen-presenting cell function, compromised natural killer (NK)-cell cytotoxicity, increased apoptosis of activated T lymphocytes, and impaired immune-cell migration to tumor sites. Strategies for relieving immunosuppression and restoring antitumor immune functions could benefit HNSCC patients. IRX-2 is a primary cell-derived biologic consisting of physiologic levels of T-helper type 1 cytokines produced by stimulating peripheral blood mononuclear cells of normal donors with phytohemagglutinin. The primary active components in IRX-2 are IL2, IL1β, IFNγ, and TNFα. In vitro, IRX-2 acts on multiple immune-system cell types, including DCs, T cells, and NK cells, to overcome tumor-mediated immunosuppression. In clinical settings, IRX-2 is administered as part of a 21-day neoadjuvant regimen, which includes additional pharmacologic agents (low-dose cyclophosphamide, indomethacin, and zinc) to promote anticancer immunoresponses. In a Phase IIA trial in 27 patients with surgically resectable, previously untreated HNSCC, neoadjuvant IRX-2 increased infiltration of T cells, B cells, and DCs into tumors and was associated with radiological reductions in tumor size. Event-free survival was 64% at 2 years, and overall 5-year survival was 65%. Follow-up and data analysis are under way in the multicenter, randomized, Phase IIB INSPIRE trial evaluating the IRX-2 regimen as a stand-alone therapy for activating the immune system to recognize and attack tumors.

Dihydromyricetin promotes autophagy and apoptosis through ROS-STAT3 signaling in head and neck squamous cell carcinoma

Chemotherapy is an effective weapon in the battle against cancer, but numerous cancer patients are either not sensitive to chemotherapy or develop drug resistance to current chemotherapy regimens. Therefore, an effective chemotherapy mechanism that enhances tumor sensitivity to chemotherapeutics is urgently needed. The aim of the present study was to determine the antitumor activity of dihydromyricetin (DHM) on head and neck squamous cell carcinoma (HNSCC) and its underlying mechanisms. We demonstrated that DHM can markedly induce apoptotic cell death and autophagy in HNSCC cells. Meanwhile, increased autophagy inhibited apoptosis. Pharmacological or genetic inhibition of autophagy further sensitized the HNSCC cells to DHM-induced apoptosis. Mechanistic analysis showed that the antitumor of DHM may be due to the activation phosphorylation of signal transducer and activator of transcription 3 (p-STAT3), which contributed to autophagy. Importantly, DHM triggered reactive oxygen species (ROS) generation in the HNSCC cells and the levels of ROS decreased with N-acetyl-cysteine (NAC), a ROS scavenger. Moreover, NAC abrogated the effects of DHM on STAT3-dependent autophagy. Overall, the following critical issues were observed: first, DHM increased the p-STAT3-dependent autophagy by generating ROS-signaling pathways in head and neck squamous cell carcinoma. Second, inhibiting autophagy could enhance DHM-induced apoptosis in head and neck squamous cell carcinoma.

Radiotherapy for locally advanced resectable T3-T4 laryngeal cancer-does laryngeal preservation strategy compromise survival?

With the advancement of chemotherapy, a laryngeal preservation (LP) strategy was explored with the aim of improving maintenance of quality of life. Induction chemotherapy (ICT) following radiotherapy (RT) was considered a viable option because of its high initial response rate without hampering of overall survival (OS). Subsequently, concurrent chemoradiotherapy (CCRT) using CDDP became the standard of care for LP, showing the best LP ratio. For enhancing treatment intensity, ICT with taxan + CDDP + 5-FU (TPF-ICT) followed by RT showed superiority over ICT with CDDP + 5-FU (PF-ICT) followed by RT. Given that almost all randomized controlled trials investigating ICT include not only operable (endpoint, LP) but also inoperable (endpoint, OS) cases, physicians are faced with a dilemma regarding application in daily practice. In addition, increased treatment intensity causes augmentation of adverse events, which might reduce compliance. Thereafter, cetuximab, an effective drug with fewer adverse effects [bioradiotherapy (BRT)], emerged as another option. However, little evidence has confirmed its superiority over RT (or CCRT) in laryngeal cancer subpopulations. In spite of these developments, the OS of patients with laryngeal cancer has not improved for several decades. In fact, several studies indicated a decrease in OS during the 1990s, probably due to overuse of CCRT. Fortunately, the latter was not the case in most institutions. Currently, no other treatment has better OS than surgery. The eligibility criteria for LP and/or surgery largely depend upon the available expertise and experience, which differ from one institution to another. Therefore, a multidisciplinary team is required for the treatment of LP.

Anti-tumor effects of metformin on head and neck carcinoma cell lines: A systematic review

Metformin is commonly used for treating type 2 diabetes, and may also reduce cancer risk. Previous studies have demonstrated the association between metformin use and a decreased risk of head and neck cancer. Therefore, the aim of the present systematic review was to summarize the available literature on the in vitro anti-tumor effects of metformin on head and neck squamous cell carcinoma (HNSCC). Research studies were obtained from Cochrane Library, Embase, LILACS, MEDLINE and PubMed databases, without time or language restrictions. Only in vitro studies analyzing the effects of metformin on HNSCC cell lines were included. The authors methodically appraised all the selected studies according to the Grading of Recommendations Assessment, Development and Evaluation method to make a judgment of the evidence quality. Of the 388 identified reports, 11 studies met the inclusion criteria and were used for qualitative analysis. These studies demonstrated that metformin is important in inhibiting cell proliferation, inducing G0/G1 cell cycle arrest and apoptosis, and in regulating proteins involved in carcinogenesis pathways, which corroborates its potential in vitro anti-tumor effects. The present systematic review highlights the biological mechanisms of metformin used alone or together with traditional therapies for cancer. Though very limited, currently available preclinical evidence shows that metformin exerts a potential effect on head and neck carcinoma.

Induction chemotherapy for squamous cell carcinomas of the oral cavity: A cumulative meta-analysis

Induction chemotherapy (ICT) is a controversial treatment for head and neck squamous cell carcinomas (HNSCC). Despite numerous randomized controlled trials (RCTs), a majority do not have enough statistical power alone to conclude ICT's treatment value among oral squamous carcinoma patients (OSCC) since many addressed HNSCC as one entity instead of by specific subtypes. By performing a systematic review and cumulative meta-analysis, we aim to determine the benefits of ICT in OSCC therapy. A literature search identified for RCTs comparing OSCC patients who received ICT against those without. Log-hazard ratio, and relative risk were used for comparison. Heterogeneity was determined using the I(2) statistic package. The primary endpoint was overall survival (OS), followed by disease-free survival (DFS), locoregional recurrence (LRR) and distant metastasis (DM) as secondary endpoints.

RESULTS

27 randomized trials were included for analysis (n=2872 patients). The shortest median follow-up was 15months whereas the longest was 11.5years. ICT does not improve OS (HR=0.947, 95% CI 0.85-1.05, p=0.318), DFS (RR=1.05, 95% CI 0.92-1.21, p=0.462) and DM (RR=0.626, CI 95% 0.361-1.086, p=0.096) compared to locoregional treatment alone. However, there was a significant improvement to LRR (RR=0.778, 95% CI 0.622-0.972, p=0.027). There is no evidence ICT improves survival outcomes for OSCC patients. However, ICT reduces locoregional recurrence of OSCC, which may need further verification.

Induction chemotherapy for head and neck cancer: is there still a role?

Integration and optimization of active systemic agents and radiosensitizers into the therapeutic regimen for head and neck cancer remains a topic of active investigation. Recent trials have not consistently supported the use of induction chemotherapy. There are several clinical scenarios in which there is a strong rationale for induction chemotherapy, such as larynx preservation, unfavorable sites and bulky locally advanced disease. The increasing prevalence of HPV-positive malignancies, impacts both interpretation of clinical research and the design of future trials. In the broad spectrum of this disease the prognosis is often dismal, with substantial room for improvement over current therapy. In the face of conflicting clinical data, we address the question of whether there remains a role for induction chemotherapy.

Advanced oropharyngeal squamous cell carcinoma: Pathogenesis, treatment, and novel therapeutic approaches

Oropharyngeal cancer accounts for approximately 2.8% of newly cancer cases. Although classically a tobacco related disease, most cases today are related to infection with human papilloma virus (HPV) and present with locally advanced tumors. HPV related tumors have been recognized as a molecularly distinct entity with higher response rates to therapy, lower rates of relapse, and improved overall survival. Treatment of oropharyngeal cancer entails a multi-disciplinary approach with concomitant chemoradiation. The role of induction chemotherapy in locally advanced tumors continues to be controversial however large studies have demonstrated no difference in survival or time to treatment failure. Surgical approaches may be employed with low volume oropharyngeal cancers and with development new endoscopic tools, more tumors are able to be resected via an endoscopic approach. Given advances in the understanding of HPV related oropharyngeal cancer, ongoing research is looking at ways to minimize toxicities via de-intensification of therapy. Unfortunately, some patients develop recurrent or metastatic disease. Novel therapeutics are currently being investigated for this patient population including immunotherapeutics. This review discusses the current understanding of the pathogenesis of oropharyngeal cancer and treatment. We also discuss emerging areas of research as it pertains to de-intensification as well novel therapeutics for the management of metastatic disease.

Effect of nisin and doxorubicin on DMBA-induced skin carcinogenesis--a possible adjunct therapy

In view of the emergence of multidrug-resistant cancer cells, there is a need for therapeutic alternatives. Keeping this in mind, the present study was aimed at evaluating the synergism between nisin (an antimicrobial peptide) and doxorubicin (DOX) against DMBA-induced skin carcinogenesis. The possible tumoricidal activity of the combination was evaluated in terms of animal bioassay observations, changes in hisotological architecture of skin tissues, in situ apoptosis assay (TUNEL assay) and in terms of oxidant and antioxidant status of the skin tissues. In vivo additive effect of the combination was evidenced by larger decreases in mean tumour burden and tumour volume in mice treated with the combination than those treated with the drugs alone. Histological observations indicated that nisin-DOX therapy causes chromatin condensation and marginalisation of nuclear material in skin tissues of treated mice which correlated well with the results of TUNEL assay wherein a marked increase in the rate of apoptosis was revealed in tissues treated with the combination. A slightly increased oxidative stress in response to the adjunct therapy as compared to dox-alone-treated group was revealed by levels of lipid peroxidation (LPO) and nitrite generation in skin tissue-treated mice. An almost similar marginal enhancement in superoxide dismutase levels corresponding with a decrease in catalase activity could also be observed in nisin + DOX-treated groups as compared to nisin and dox-alone-treated groups. These results point towards the possible use of nisin as an adjunct to doxorubicin may help in developing alternate strategies to combat currently developing drug resistance in cancer cells.