Background: Colorectal cancer (CRC) is one of the most common types of cancer diagnosed worldwide with high morbidity; drug resistance is often responsible for treatment failure in CRC. Non-coding RNAs (ncRNAs) play distinct regulatory roles in tumorigenesis, cancer progression and chemoresistance. Methods: Α literature search was conducted in PubMed database in order to sum up and discuss the role of exosomal ncRNAs (ex-ncRNAs) in CRC drug resistance/response and their possible mechanisms. Results: Thirty-six (36) original research articles were identified; these included exosome or extracellular vesicle (EV)-containing microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and small-interfering (siRNAs). No studies were found for piwi-interacting RNAs. Conclusions: Exosomal transfer of ncRNAs has been documented as a new mechanism of CRC drug resistance. Despite being in its infancy, it has emerged as a promising field for research in order to (i) discover novel biomarkers for therapy monitoring and/or (ii) reverse drug desensitization.

Gastric cancer (GC) is the fifth most commonly diagnosed malignancy and the fourth leading cause of cancer death worldwide. Skin metastases from internal organs are rare; skin metastasis from GC occurs even more rarely than skin metastases originating from other organs, and is associated with systematic disease and poor prognosis. The present study described an interesting and rare case of an extensive skin rash in a 42-year-old man diagnosed with GC, which was mainly affecting his left hemithorax, abdomen and back. The rash masqueraded as erysipelas and was initially treated as such; however, it did not respond to antibiotics, corticosteroids and antihistamines. Due to its persistence and location, the rash was biopsied and GC metastasis was confirmed. Thirdline chemotherapy was administered and the rash decreased in size; however, the patient suffered from disease deterioration with lung metastases and respiratory failure. The patient eventually died 4 months after the diagnosis of skin metastasis. In conclusion, cutaneous metastasis should be considered as a late and difficult to treat metastasis of GC, which requires high surveillance from medical oncologists, and a multidisciplinary approach for prompt and accurate diagnosis.

Introduction: During the evolution of the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic, several drug candidates have been proposed for repositioning towards a quest for more effective treatments. Methodology: We reviewed recent literature (Pubmed, Google, Clinicaltrials.gov), as of the middle of May 2021, for evidence regarding the potential benefit from poly(ADP-ribose)-polymerase inhibitors and vascular endothelial growth factor blockade in severe SARS-CoV-2 infection. Results: poly(ADP-ribose)-polymerase inhibitors have been suggested as potential agents against coronavirus disease 2019 (COVID-19) by a variety of mechanisms. vascular endothelial growth factor-associated vascular permeability is implicated with increased vascular leakage and pulmonary oedema. Thus, anti-angiogenesis factors, such as bevacizumab are being investigated in critically ill COVID-19 patients. Conclusions: The synergistic potential of these two classes of inhibitors in severe COVID-19 management could be beneficial. Further research should be carried out in order to support this hypothesis.

BRAF/MEK inhibitors are considered standard of care in the treatment of advanced BRAF-mutated malignant melanoma, and have been, in rare cases, associated with granulomatous reactions, mostly limited to skin lesions. The present study reported the case of a patient with metastatic melanoma developing a sarcoid-like reaction manifesting as asymptomatic mediastinal and right hilar lymphadenopathy while on antineoplastic therapy with dabrafenib and trametinib. To the best of our knowledge, this is the first reported case of isolated lymphadenopathy as a manifestation of drug-induced sarcoid-like reaction under dabrafenib and trametinib. Overall, only 17 other cases of granulomatosis have been reported in the literature. Although uncommon, such reactions should be considered in the differential diagnosis of lymph node enlargement, and distinguishing them from tumor progress is important and can be challenging in clinical practice.

Colorectal cancer represents a leading cause of cancer-related morbidity and mortality. Despite improvements, chemotherapy remains the backbone of colorectal cancer treatment. The aim of this study is to investigate the variation of circulating microRNA expression profiles and the response to irinotecan-based treatment in metastatic colorectal cancer and to identify relevant target genes and molecular functions. Serum samples from 95 metastatic colorectal cancer patients were analyzed. The microRNA expression was tested with a NucleoSpin miRNA kit (Machnery-Nagel, Germany), and a machine learning approach was subsequently applied for microRNA profiling. The top 10 upregulated microRNAs in the non-responders group were hsa-miR-181b-5p, hsa-miR-10b-5p, hsa-let-7f-5p, hsa-miR-181a-5p, hsa-miR-181d-5p, hsa-miR-301a-3p, hsa-miR-92a-3p, hsa-miR-155-5p, hsa-miR-30c-5p, and hsa-let-7i-5p. Similarly, the top 10 downregulated microRNAs were hsa-let-7d-5p, hsa-let-7c-5p, hsa-miR-215-5p, hsa-miR-143-3p, hsa-let-7a-5p, hsa-miR-10a-5p, hsa-miR-142-5p, hsa-miR-148a-3p, hsa-miR-122-5p, and hsa-miR-17-5p. The upregulation of microRNAs in the miR-181 family and the downregulation of those in the let-7 family appear to be mostly involved with non-responsiveness to irinotecan-based treatment.