Study of Gemcitabine Plus Nab-Paclitaxel-Based Chemotherapy Regimen as First-Line Treatment in Metastatic Pancreatic Carcinoma

Background The purpose of this study was to study the effectiveness of gemcitabine and nab-paclitaxel combination as first-line chemotherapy regimen for the treatment of metastatic pancreatic cancer. There is scarcity of data regarding efficacy and toxicity profile of this combination in Indian population. Aims and Objectives The primary aim of this study was to assess efficacy of this regimen, for which evaluation done in terms of the objective response rate, progression-free survival (PFS), and overall survival. Safety data were also evaluated. Materials and Methods In this prospective study, gemcitabine plus nab-paclitaxel combination chemotherapy was given as first line in metastatic pancreatic carcinoma patients till progression or appearance of grade 3/4 toxicities with treatment. Results The study was performed in 30 patients comprising 18 (60%) males and 12 (40%) females. The median age was 60 years. Median number of cycles administered were six cycles per patient. Seventeen patients (56.67%) had a partial response and 0% had complete response. A total of seven (23.3%) patients progressed on chemotherapy and six (20%) had stable disease (SD). The disease control rate (responses and SD) was 76.7%. The median PFS was 5.75 months. There was no statistically significant difference in terms of response rates and baseline CA 19-9 levels. Most common toxicities were hematological toxicities with rates of grade 3/4 anemia and neutropenia of 20%. Among nonhematological toxicities, nausea (46.67%) and fatigue (30%) were the commonest. Conclusion Combination of gemcitabine and nab-paclitaxel is active and well tolerated in advanced pancreatic carcinoma. To the best of our knowledge, this is the first such study conducted in India.

Identifying and Validating an Acidosis-Related Signature Associated with Prognosis and Tumor Immune Infiltration Characteristics in Pancreatic Carcinoma

Background. Acidosis in the tumor microenvironment (TME) is involved in tumor immune dysfunction and tumor progression. We attempted to develop an acidosis-related index (ARI) signature to improve the prognostic prediction of pancreatic carcinoma (PC). Methods. Differential gene expression analyses of two public datasets (GSE152345 and GSE62452) from the Gene Expression Omnibus database were performed to identify the acidosis-related genes. The Cancer Genome Atlas–pancreatic carcinoma (TCGA-PAAD) cohort in the TCGA database was set as the discovery dataset. Univariate Cox regression and the Kaplan–Meier method were applied to screen for prognostic genes. The least absolute shrinkage and selection operator (LASSO) Cox regression was used to establish the optimal model. The tumor immune infiltrating pattern was characterized by the single-sample gene set enrichment analysis (ssGSEA) method, and the prediction of immunotherapy responsiveness was conducted using the tumor immune dysfunction and exclusion (TIDE) algorithm. Results. We identified 133 acidosis-related genes, of which 37 were identified as prognostic genes by univariate Cox analysis in combination with the Kaplan–Meier method ( p values of both methods < 0.05). An acidosis-related signature involving seven genes (ARNTL2, DKK1, CEP55, CTSV, MYEOV, DSG2, and GBP2) was developed in TCGA-PAAD and further validated in GSE62452. Patients in the acidosis-related high-risk group consistently showed poorer survival outcomes than those in the low-risk group. The 5-year AUCs (areas under the curve) for survival prediction were 0.738 for TCGA-PAAD and 0.889 for GSE62452, suggesting excellent performance. The low-risk group in TCGA-PAAD showed a higher abundance of CD8+ T cells and activated natural killer cells and was predicted to possess an elevated proportion of immunotherapeutic responders compared with the high-risk counterpart. Conclusions. We developed a reliable acidosis-related signature that showed excellent performance in prognostic prediction and correlated with tumor immune infiltration, providing a new direction for prognostic evaluation and immunotherapy management in PC.

Intrinsic nucleus-targeted ultra-small metal–organic framework for the type I sonodynamic treatment of orthotopic pancreatic carcinoma

Background Sonodynamic therapy (SDT) strategies exhibit a high tissue penetration depth and can achieve therapeutic efficacy by facilitating the intertumoral release of reactive oxygen species (ROS) with a short lifespan and limited diffusion capabilities. The majority of SDT systems developed to date are of the highly O2-dependent type II variety, limiting their therapeutic utility in pancreatic cancer and other hypoxic solid tumor types. Results Herein, a nucleus-targeted ultra-small Ti-tetrakis(4-carboxyphenyl)porphyrin (TCPP) metal–organic framework (MOF) platform was synthesized and shown to be an effective mediator of SDT. This MOF was capable of generating large quantities of ROS in an oxygen-independent manner in response to low-intensity ultrasound (US) irradiation (0.5 W cm−2), thereby facilitating both type I and type II SDT. This approach thus holds great promise for the treatment of highly hypoxic orthotopic pancreatic carcinoma solid tumors. This Ti-TCPP MOF was able to induce in vitro cellular apoptosis by directly destroying DNA and inducing S phase cell cycle arrest following US irradiation. The prolonged circulation, high intratumoral accumulation, and nucleus-targeting attributes of these MOF preparations significantly also served to significantly inhibit orthotopic pancreatic tumor growth and prolong the survival of tumor-bearing mice following Ti-TCPP + US treatment. Moreover, this Ti-TCPP MOF was almost completely cleared from mice within 7 days of treatment, and no apparent treatment-associated toxicity was observed. Conclusion The nucleus-targeted ultra-small Ti-TCPP MOF developed herein represents an effective approach to the enhanced SDT treatment of tumors in response to low-intensity US irradiation. Graphic abstract