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 Tuhina Khan and Nicola Relitti contributed equally to this work. and on future therapeutic perspectives combining the early detection of relevant biomarkers with drug discovery for the treatment of OSCC and ESCC. K E Y W O R D S autophagy, autophagy modulators, biomarkers, esophageal squamous cell carcinoma, exosomes, oral squamous cell carcinoma, targeted therapy 1 | INTRODUCTION Oral squamous cell carcinoma (OSCC) is the predominant malignant neoplasm of the oral cavity followed by verrucous carcinoma, undifferentiated carcinoma, and small salivary adenocarcinoma. 1 Esophageal squamous cell carcinoma (ESCC) is the first histological type and accounts for 80% of cases of esophageal cancer. 2 OSCC and ESCC are indicated as one of the most common cancers by the International Union Against Cancer with an annual incidence of 275 000 and 456 000 cases worldwide, respectively. 3,4 The primary etiology in both OSCC and ESCC is attributed to the environmental factors (tobacco abuse, alcohol consumption), genetic factors (eg, mutations in enzymes), viral factors (human papilloma virus [HPV] infection), and/or the coexistence of these factors. Alcohol intake and tobacco use are responsible for at least 75% of these carcinomas. The underlying initiation and progression mechanisms of OSCC and ESCC are generally characterized by the accumulation of serial epigenetic and genetic alterations, which eventually lead to uncontrolled proliferation of the mutated cells, followed by vigorous cell division. 5,7 Early-stage OSCC detection displays an 80% survival rate at 5 years, while detection at advanced stage leads to survival rates ranging from 20% to 40%. 6 In ESCC, the 5-year survival rate for early-stage detection may reach 85%, whereas a dr...

Telomeres are protective chromosomal ends that shield the chromosomes from DNA damage, exonucleolytic degradation, recombination, and end-to-end fusion. Telomerase is a ribonucleoprotein that adds TTAGGG tandem repeats to the telomeric ends. It has been observed that 85 to 90% of human tumors express high levels of telomerase, playing a crucial role in the development of cancers. Interestingly, the telomerase activity is generally absent in normal somatic cells. This selective telomerase expression has driven scientists to develop novel anti-cancer therapeutics with high specificity and potency. Several advancements have been made in this area, which is reflected by the enormous success of the anticancer agent Imetelstat. Since the discovery of Imetelstat, several research groups have contributed to enrich the therapeutic arsenal against cancer. Such contributions include the application of new classes of small molecules, peptides, and hTERT-based immunotherapeutic agents (p540, GV1001, GRNVAC1 or combinations of these such as Vx-001). Many of these therapeutic tools are under different stages of clinical trials and have shown promising outcomes. In this review, we highlight the current status of telomerase-based cancer therapeutics and the outcome of these investigations.

Microtubule-targeting agents (MTAs) are a class of clinically successful anti-cancer drugs. The emergence of multidrug resistance to MTAs imposes the need for developing new MTAs endowed with diverse mechanistic properties. Benzoxazepines were recently identified as a novel class of MTAs. These anticancer agents were thoroughly characterized for their antitumor activity, although, their exact mechanism of action remained elusive. Combining chemical, biochemical, cellular, bioinformatics and structural efforts we developed improved pyrrolonaphthoxazepines antitumor agents and their mode of action at the molecular level was elucidated. Compound 6j, one of the most potent analogues, was confirmed by X-ray as a colchicine-site MTA. A comprehensive structural investigation was performed for a complete elucidation of the structure-activity relationships. Selected pyrrolonaphthoxazepines were evaluated for their effects on cell cycle, apoptosis and differentiation in a variety of cancer cells, including multidrug resistant cell lines. Our results define compound 6j as a potentially useful optimized hit for the development of effective compounds for treating drug-resistant tumors.

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Leishmania spp. are responsible for up to 1 million new cases each year. The current therapeutic arsenal against Leishmania is largely inadequate, and there is an urgent need for better drugs. Trypanothione reductase (TR) represents a druggable target since it is essential for the parasite and not shared by the human host. Here, we report the optimization of a novel class of potent and selective LiTR inhibitors realized through a concerted effort involving X-ray crystallography, synthesis, structure–activity relationship (SAR) investigation, molecular modeling, and in vitro phenotypic assays. 5-Nitrothiophene-2-carboxamides 3, 6e, and 8 were among the most potent and selective TR inhibitors identified in this study. 6e and 8 displayed leishmanicidal activity in the low micromolar range coupled to SI > 50. Our studies could pave the way for the use of TR inhibitors not only against leishmaniasis but also against other trypanosomatidae due to the structural similarity of TR enzymes.