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Long-standing thyroid swellings can present therapeutic and diagnostic challenges. Although benign, these nodules can harbour malignancies of diverse lineages ranging from those of follicular cell origin to rare malignancies such as lymphomas and paragangliomas. Here, the authors are sharing their three clinical experiences with thyroid neoplasms of long duration. The first case is a 42-year-old male patient who presented with an anterior neck swelling of 12 years’ duration. Postoperatively, a diagnosis of Mucosa-associated Lymphoid Tissue (MALT) lymphoma was made based on histopathology and immunohistochemistry. In the second case, a 43-year-old male presented with a neck swelling with eight years of history. Intraoperatively, the lesion was found to be locally aggressive with infiltration into the strap muscles and trachea. A tissue diagnosis of paraganglioma of the thyroid gland was made postoperatively. The third case involves a 72-year-old female who had undergone a left thyroidectomy 10 years back and presented to the Outpatient Department (OPD) with a history of right-sided neck swelling associated with dysphagia and a change in voice. The patient was diagnosed with anaplastic carcinoma, specifically squamous cell carcinoma. Thyroid lesions of abnormally large size create intraoperative problems concerning securing an adequate airway, locating anatomical structures, especially the Recurrent Laryngeal Nerve (RLN), parathyroids, and great vessels of the neck. Postoperatively, the tissue features may be very uncharacteristic, making reaching a proper diagnosis difficult. The use of immunohistochemistry helps in determining the cell lineage and type of malignancy.

Abstract Detecting pancreatic duct adenocarcinoma (PDAC) in its early stages and predicting late‐stage patient prognosis undergoing chemotherapy is challenging. This work shows that the activation of specific oncogenes leads to elevated expression of mRNAs and their corresponding proteins in extracellular vesicles (EVs) circulating in blood. Utilizing an immune lipoplex nanoparticle (ILN) biochip assay, these findings demonstrate that glypican 1 (GPC1) mRNA expression in the exosomes‐rich (Exo) EV subpopulation and GPC1 membrane protein (mProtein) expression in the microvesicles‐rich (MV) EV subpopulation, particularly the tumor associated microvesicles (tMV), served as a viable biomarker for PDAC. A combined analysis effectively discriminated early‐stage PDAC patients from benign pancreatic diseases and healthy donors in sizable clinical from multiple hospitals. Furthermore, among late‐stage PDAC patients undergoing chemotherapy, lower GPC1 tMV‐mProtein and Exo‐mRNA expression before treatment correlated significantly with prolonged overall survival. These findings underscore the potential of vesicular GPC1 expression for early PDAC screenings and chemotherapy prognosis.

Rett syndrome is an acquired progressive neurodevelopmental disorder caused by de novo mutations in the X-linked MECP2 gene which encodes a pleiotropic protein that functions as a global transcriptional regulator and a chromatin modifier. Rett syndrome predominantly affects heterozygous females while affected male hemizygotes rarely survive. Gene therapy of Rett syndrome has proven challenging due to a requirement for stringent regulation of expression with either over- or under-expression being toxic. Ectopic expression of MECP2 in conjunction with regulatory miRNA target sequences has achieved some success, but the durability of this approach remains unknown. Here we evaluated a nuclease-free homologous recombination (HR)-based genome editing strategy to correct mutations in the MECP2 gene. The stem cell-derived AAVHSCs have previously been shown to mediate seamless and precise HR-based genome editing. We tested the ability of HR-based genome editing to correct pathogenic mutations in Exons 3 and 4 of the MECP2 gene and restore the wild type sequence while preserving all native genomic regulatory elements associated with MECP2 expression, thus potentially addressing a significant issue in gene therapy for Rett syndrome. Moreover, since the mutations are edited directly at the level of the genome, the corrections are expected to be durable with progeny cells inheriting the edited gene. The AAVHSC MECP2 editing vector was designed to be fully homologous to the target MECP2 region and to insert a promoterless Venus reporter at the end of Exon 4. Evaluation of AAVHSC editing in a panel of Rett cell lines bearing mutations in Exons 3 and 4 demonstrated successful correction and rescue of expression of the edited MECP2 gene. Sequence analysis of edited Rett cells revealed successful and accurate correction of mutations in both Exons 3 and 4 and permitted mapping of HR crossover events. Successful correction was observed only when the mutations were flanked at both the 5′ and 3′ ends by crossover events, but not when both crossovers occurred either exclusively upstream or downstream of the mutation. Importantly, we concluded that pathogenic mutations were successfully corrected in every Rett line analyzed, demonstrating the therapeutic potential of HR-based genome editing.