Nakka, Naga Malleswara Rao

Abstract Background Glioblastoma (GBM) is the most common high-grade primary malignant brain tumor, characterized by a notably poor prognosis. Current treatments for GBM have shown limited effectiveness in improving patient survival, highlighting the urgent need for novel therapeutic strategies. Combination therapy offers significant potential in overcoming resistance by targeting multiple signaling pathways; however, it often comes with increased toxicity compared to monotherapy. Co-encapsulating multiple therapeutic agents into a tumor-targeted drug delivery platform holds promise for overcoming these limitations and improving treatment outcomes. Methods We developed a tumor-targeted liposomal nanoformulation (TTL) using phospholipids, cholesterol, DSPE-(PEG)2000-OMe, and a proprietary tumor-targeting peptide (TTP). The TTL was loaded with everolimus (TTL-E), vinorelbine (TTL-V), rapamycin (TTL-R), a combination (TTL-EV), or (TTL-RV). These formulations were tested in vivo on orthotopic GBM mice, combined with temozolomide and radiation. RNA sequencing was performed to identify molecular and transcriptome changes post-treatment. Results TTL demonstrated tumor-specific uptake, effectively delivering drugs to GBM tumors. TTL-EV and TTL-RV outperformed single-drug formulations. Radiation combined with TTL-EV/RV improved tumor growth inhibition and survival, while temozolomide provided minimal benefit. Transcriptome analysis revealed differentially expressed genes (DEGs) linked to DNA damage repair, cell cycle, metabolism, and extracellular matrix pathways. Conclusion TTL crossed the blood-brain barrier, targeting tumors effectively. Radiation plus TTL-EV/RV enhanced tumor suppression and survival in GBM models. Gene expression analysis identified DEGs related to DNA damage and cell death. Mechanistic studies suggest TTL-EV plus radiation inhibits mTOR/MAPK pathways and sensitizes tumors to radiation. These findings offer a potential approach for improving GBM treatment.

Importance The prognosis of advanced pancreaticobiliary tumors is poor. Next-generation sequencing (NGS) of tissue samples is utilized to identify actionable alterations, but there are occasional limitations due to inadequate tissue acquisition. Circulating tumor DNA (ctDNA) is an alternative method, but its correlation with tissue-based NGS remains unexplored. Objectives To assess the mutation concordance (mCR) rates between ctDNA and tissue testing for patients with pancreatic ductal adenocarcinoma (PDAC) and cholangiocarcinoma (CC) and to evaluate how ctDNA performs as a treatment response biomarker. Design, Setting, and Participants This retrospective cohort study was conducted among patients with PDAC and CC treated at academic institutions from January 2014 to January 2025. Patients underwent ctDNA testing using 1 platform and tissue NGS testing using 2 platforms. Main Outcomes and Measures mCR, which measures the shared gene alterations observed by both ctDNA and tissue-based NGS testing, was calculated using the Spearman correlation for PDAC and CC. The performance of ctDNA as a treatment response biomarker was assessed by comparing serial ctDNA data with restaging scans and cancer antigen 19-9 levels in patients with PDAC. Results Our cohort included 790 patients: 570 with advanced PDAC (265 [46.5%] female; median [IQR] age, 64 [33-84] years) and 220 with advanced CC (95 [43.2%] female; median [IQR] age, 66 [42-88] years). Overall, 461 patients with PDAC (80.9%) and 192 patients with CC (87.2%) underwent ctDNA testing, while 239 patients with PDAC (41.9%) and 70 patients with CC (31.8%) had tissue NGS testing. Among patients with PDAC, 85 of 130 patients (65.4%) showed shared specific gene alterations between ctDNA and tissue testing; there was a significant mCR, with a Spearman correlation of 0.47 (95% CI, 0.28-0.62; P < .001). For patients with CC, 32 of 48 (66.7%) had shared alterations between ctDNA and tissue testing; there was a significant mCR, with a Spearman correlation of 0.56 (95% CI, 0.35-0.70; P < .001). A subgroup analysis of patients with PDAC who underwent serial ctDNA testing suggested that new TP53 subclones and increased ctDNA variant allele frequency levels of TP53 and KRAS were associated with higher odds of progressive disease (eg, increased TP53 frequency: odds ratio, 7.28; 95% CI, 2.15-24.66; P = .001). Conclusions and Relevance In this cohort study of patients with pancreaticobiliary tumors, there was a significant mCR between ctDNA and tissue NGS testing. Additionally, results suggest that ctDNA might detect resistant clones and enable assessment of treatment response.

Pancreatic cancer ranks third in cancer related deaths in the USA, however, no reliable theragnostic biomarker exists for the disease. The community of bacteria within the body can become dysbiotic and promote cancer through inflammation and other means. The objectives of this study were to determine the identity and abundance of bacterial species in the gut of mice before and after development of pancreatic cancer. As there can be significant variation in the genomes of different strains of bacterial species, a metagenome analysis was also performed. We hypothesized that there would be significant variation in species and genes of the gastrointestinal tract of mice before and after xenografting with pancreatic cancer. A decrease in ecological diversity was also predicted. Fifteen female SCID mice were divided into three cages. To develop the SubQ pancreatic cancer model, 5 X 106 Panc1 cells were injected at the flank. Fecal materials were collected prior to tumor cell implantation and after tumor development. DNA was extracted from the fecal material. For phylogenetic analysis the seven variable regions of the 16S rRNA gene were amplified and sequenced. Metagenomic analysis was performed as well. Average tumor size in mice after 40 days was ∼ 32 mm3. Microbial diversity was decreased in two out of the three groups of mice. Principle component analysis showed major differences between all samples. There were at least 15 OTUs in each set of samples specific to pretumor mice and 15 OTUs specific to tumor bearing mice. One genus of bacteria, Alistipes, was specific to each set of tumor bearing mice. Taxa at significantly increased abundances in tumor bearing mice included Prevotellaceae and Porpyromonadaceae. Moreover, there were several gene functions that were enriched in tumor bearing mice. This study produced data that demonstrates that there is a link between health status and the gut microbiome. However, this is not a new idea. This study could serve as foundation to establish a gut microbiota profile of pancreatic cancer. Precision medicine is becoming more common due to the decreasing costs of DNA sequencing. The findings of our investigation strengthens the hypothesis that there is an interaction between gut microbiome and pancreatic cancer development and bacteria or bacterial genes could serve as theragnostic biomarker for pancreatic cancer. Acknowledgement: This research was supported by NIH Grant# T34-GM100831, NSF-NOYCE Graduate student training award, a US Department of Education Graduate student training award to Elizabeth City State University Campus of The University of North Carolina and a University of North Carolina Collaboratory Grant award to Dr. H. Banerjee and Dr. Colby Hunter. Citation Format: Gabrielle Morgan, Colby Hunter, Michael Hall, Narendra Banerjee, Erik Armstrong, Kanisha McNeil, Karington Perry, Santanu Bhattacharya, Hirendra N. Banerjee, Krishna K. Rachamala, Shamit Dutta, Naga M. Nakka. Phylogenetic and metagenomic analysis of the human pancreatic cancer microbiome [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6526.

The zebrafish (Danio rerio) has emerged as an appreciated and versatile model organism for studying cardiovascular and metabolic diseases, offering unique advantages for both basic research and drug discovery. The genetic conservation between zebrafish and humans and their high fecundity and transparent embryos allow for efficient large-scale genetic and drug-oriented screening studies. Zebrafish possess a simplified cardiovascular system that shares similarities with mammals, making them particularly suitable for modeling various aspects of heart development, function, and disease. The transparency of zebrafish embryos enables the real-time visualization of cardiovascular dynamics, offering insights into early embryonic events and facilitating the study of heart-related anomalies. In metabolic research, zebrafish provide a cost-effective platform for modeling obesity, type 2 diabetes, hyperlipidemia, and other metabolic disorders. Their high reproductive rate allows for the generation of large cohorts for robust statistical analyses, while advanced genetic tools, such as CRISPR/Cas9, enable precise gene editing with which to model specific genetic mutations associated with human diseases. Zebrafish metabolic models have been instrumental in elucidating the molecular mechanisms underlying metabolic diseases, studying the effects of environmental factors, and identifying potential therapeutic targets. Additionally, the permeability of zebrafish embryos to small molecules facilitates drug discovery and screening, offering a rapid and economical approach to identifying compounds with therapeutic potential. In conclusion, zebrafish cardiovascular and metabolic disease models continue to contribute significantly to our perception of disease pathogenesis, providing a platform for translational research and developing novel therapeutic interventions. The versatility, scalability, and genetic manipulability of zebrafish position them as an invaluable asset in unraveling the complexities of cardiovascular and metabolic diseases. This review presents an overview of the zebrafish model’s key features and contributions to investigating cardiovascular and metabolic disorders. We discuss the benefits and drawbacks of using zebrafish models to study human disease and the critical findings revealed by the progress in this endeavor to date.

Abstract Background Renal cell carcinoma (RCC) was historically considered to be less responsive to radiation therapy (RT) compared to other cancer indications. However, advancements in precision high-dose radiation delivery through single-fraction and multi-fraction stereotactic ablative radiotherapy (SABR) have led to better outcomes and reduced treatment-related toxicities, sparking renewed interest in using RT to treat RCC. Moreover, numerous studies have revealed that certain therapeutic agents including chemotherapies can increase the sensitivity of tumors to RT, leading to a growing interest in combining these treatments. Here, we developed a rational combination of two radiosensitizers in a tumor-targeted liposomal formulation for augmenting RT in RCC. The objective of this study is to assess the efficacy of a tumor-targeted liposomal formulation combining the mTOR inhibitor everolimus (E) with the survivin inhibitor YM155 (Y) in enhancing the sensitivity of RCC tumors to radiation. Experimental Design: We slightly modified our previously published tumor-targeted liposomal formulation to develop a rational combination of E and Y in a single liposomal formulation (EY-L) and assessed its efficacy in RCC cell lines in vitro and in RCC tumors in vivo. We further investigated how well EY-L sensitizes RCC cell lines and tumors toward radiation and explored the underlying mechanism of radiosensitization. Results EY-L outperformed the corresponding single drug-loaded formulations E-L and Y-L in terms of containing primary tumor growth and improving survival in an immunocompetent syngeneic mouse model of RCC. EY-L also exhibited significantly higher sensitization of RCC cells towards radiation in vitro than E-L and Y-L. Additionally, EY-L sensitized RCC tumors towards radiation therapy in xenograft and murine RCC models. EY-L mediated induction of mitotic catastrophe via downregulation of multiple cell cycle checkpoints and DNA damage repair pathways could be responsible for the augmentation of radiation therapy. Conclusion Taken together, our study demonstrated the efficacy of a strategic combination therapy in sensitizing RCC to radiation therapy via inhibition of DNA damage repair and a substantial increase in mitotic catastrophe. This combination therapy may find its use in the augmentation of radiation therapy during the treatment of RCC patients.

Glioblastoma multiforme (GBM) is a primary malignant brain tumor characterized by a high grade of malignancy and an extremely unfavorable prognosis. The current efficacy of established treatments for GBM is insufficient, necessitating the prompt development of novel therapeutic approaches. The progress made in the fundamental scientific understanding of GBM is swiftly translated into more advanced stages of therapeutic studies. Despite extensive efforts to identify new therapeutic approaches, GBM exhibits a high mortality rate. The current efficacy of treatments for GBM patients is insufficient due to factors such as tumor heterogeneity, the blood–brain barrier, glioma stem cells, drug efflux pumps, and DNA damage repair mechanisms. Considering this, pharmacological cocktail therapy has demonstrated a growing efficacy in addressing these challenges. Towards this, various forms of immunotherapy, including the immune checkpoint blockade, chimeric antigen receptor T (CAR T) cell therapy, oncolytic virotherapy, and vaccine therapy have emerged as potential strategies for enhancing the prognosis of GBM. Current investigations are focused on exploring combination therapies to mitigate undesirable side effects and enhance immune responses against tumors. Furthermore, clinical trials are underway to evaluate the efficacy of several strategies to circumvent the blood–brain barrier (BBB) to achieve targeted delivery in patients suffering from recurrent GBM. In this review, we have described the biological and molecular targets for GBM therapy, pharmacologic therapy status, prominent resistance mechanisms, and new treatment approaches. We also discuss these promising therapeutic approaches to assess prospective innovative therapeutic agents and evaluated the present state of preclinical and clinical studies in GBM treatment. Overall, this review attempts to provide comprehensive information on the current status of GBM therapy.