Keyword: Colorectal Neoplasms
2 results found.
Congress Abstract
Oncology, Nuclear Medicine and Transplantology, 2(3, Suppl. 1), 2026, onmt_A17, https://doi.org/10.63946/onmt/19328
ABSTRACT:
Introduction: Cdc42 is a small Rho GTPase that regulates various cellular functions controlling cell motility, shape, and growth through actin cytoskeleton dynamics. This protein is also known to be overexpressed in various diseases, particularly in cancer. Colorectal cancer is a common malignancy with a high mortality rate. Elevated Cdc42 expression is observed in colorectal cancer. Inhibition of Cdc42 can significantly slow the growth and metastasis of colorectal cancer but often causes severe side effects. To address this issue, PLGA-PEG nanoparticles functionalized with DNA aptamers were developed to selectively deliver the Cdc42 inhibitor CASIN to tumor cells by targeting nucleolin—a protein that is overexpressed in colorectal cancer.
Materials and Methods: The nucleolin-targeting aptamer AS1411 (5'-FAM–GGT GGT GGT GGT TGT GGT GGT GGT GG–3'-NH2) was synthesized as a 28-base single-stranded DNA oligonucleotide modified with a fluorescein label at the 5' end and an amine group at the 3' end. PLGA-PEG-NHS nanoparticles conjugated with the AS1411 aptamer were prepared using the nanoprecipitation method. Conjugation efficiency was assessed by DNA quantification, as well as by fluorescence microscopy and Raman spectroscopy. Binding affinity and specificity of aptamer-functionalized nanoparticles to nucleolin-positive cancer cells were confirmed by flow cytometry.
Results: AS1411-functionalized PLGA-PEG-NHS nanoparticles loaded with CASIN had an average size of approximately 129 nm (polydispersity index 0.259) and a zeta potential of –52.3 mV. Encapsulation efficiency was 38.1%, and drug loading content was 7.35%. CASIN release occurred in two phases: an initial burst release followed by a gradual release over 48 hours. In vitro, these nanoparticles significantly suppressed the growth of colorectal cancer cells (HT29, SW620, HCT116) and substantially reduced HT29 cell migration, while AS1411-modified nanoparticles without CASIN had minimal effects. Furthermore, the nanoparticles significantly reduced the migratory and invasive capacity of colorectal cancer cells.
Conclusion: Overall, this targeted nanoparticle system represents a promising strategy for improving the precision and efficacy of colorectal cancer treatment. This research was funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP26100973) and Nazarbayev University under Collaborative Research Project (CRP) No. 211123CRP1611.
Materials and Methods: The nucleolin-targeting aptamer AS1411 (5'-FAM–GGT GGT GGT GGT TGT GGT GGT GGT GG–3'-NH2) was synthesized as a 28-base single-stranded DNA oligonucleotide modified with a fluorescein label at the 5' end and an amine group at the 3' end. PLGA-PEG-NHS nanoparticles conjugated with the AS1411 aptamer were prepared using the nanoprecipitation method. Conjugation efficiency was assessed by DNA quantification, as well as by fluorescence microscopy and Raman spectroscopy. Binding affinity and specificity of aptamer-functionalized nanoparticles to nucleolin-positive cancer cells were confirmed by flow cytometry.
Results: AS1411-functionalized PLGA-PEG-NHS nanoparticles loaded with CASIN had an average size of approximately 129 nm (polydispersity index 0.259) and a zeta potential of –52.3 mV. Encapsulation efficiency was 38.1%, and drug loading content was 7.35%. CASIN release occurred in two phases: an initial burst release followed by a gradual release over 48 hours. In vitro, these nanoparticles significantly suppressed the growth of colorectal cancer cells (HT29, SW620, HCT116) and substantially reduced HT29 cell migration, while AS1411-modified nanoparticles without CASIN had minimal effects. Furthermore, the nanoparticles significantly reduced the migratory and invasive capacity of colorectal cancer cells.
Conclusion: Overall, this targeted nanoparticle system represents a promising strategy for improving the precision and efficacy of colorectal cancer treatment. This research was funded by the Science Committee of the Ministry of Science and Higher Education of the Republic of Kazakhstan (Grant No. AP26100973) and Nazarbayev University under Collaborative Research Project (CRP) No. 211123CRP1611.
Congress Abstract
Oncology, Nuclear Medicine and Transplantology, 2(3, Suppl. 1), 2026, onmt_A18, https://doi.org/10.63946/onmt/19255
ABSTRACT:
Introduction: Colorectal cancer remains one of the leading causes of cancer morbidity and mortality. Timely detection of metastases and assessment of treatment efficacy are important tasks in modern oncology. PET/CT with 18F-FDG has limitations related to physiological uptake of the radiopharmaceutical in the intestine and variable sensitivity across different histological tumor types. The use of 68Ga-FAPI, which has high affinity for tumor stroma and low background uptake, is a promising alternative.
Objective: To evaluate the diagnostic value of PET/CT with 68Ga-FAPI in detecting colorectal cancer metastases and monitoring treatment efficacy.
Materials and Methods: The study included 311 patients with histologically verified colorectal cancer examined between January 2024 and January 2026. The study had a retrospective-prospective design. All patients underwent PET/CT using 68Ga-FAPI. Radiopharmaceutical distribution, the presence of metastatic and additional suspicious lesions, as well as dynamic changes during treatment were assessed. Statistical analysis was performed in Microsoft Excel, calculating mean, median, and SUVmax range. The study was approved by the Local Bioethics Committee of the "Astana Medical University" NJSC (Decision No. 11 dated 27.02.2026).
Results: The mean age of patients was 58.5 years (range 17–87 years); 171 (55.0%) were women and 140 (45.0%) were men. Adenocarcinoma predominated (87%), predominantly G2; the majority of patients had stage II–III disease. Metastases were detected in 31.2% of patients, most frequently in the liver and lymph nodes; recurrence was observed in 13.0%. Additional suspicious lesions requiring verification were identified in 40% of patients. The mean SUVmax of metastatic lesions was 6.46 (range 1.1–13.8), for recurrence – 5.78 (range 2.6–9.5), and for suspicious lesions – 4.02.
Conclusions: PET/CT using 68Ga-FAPI is a promising imaging modality for colorectal cancer, allowing detection of metastatic and additional suspicious lesions and assessment of dynamic changes during antitumor treatment.
Objective: To evaluate the diagnostic value of PET/CT with 68Ga-FAPI in detecting colorectal cancer metastases and monitoring treatment efficacy.
Materials and Methods: The study included 311 patients with histologically verified colorectal cancer examined between January 2024 and January 2026. The study had a retrospective-prospective design. All patients underwent PET/CT using 68Ga-FAPI. Radiopharmaceutical distribution, the presence of metastatic and additional suspicious lesions, as well as dynamic changes during treatment were assessed. Statistical analysis was performed in Microsoft Excel, calculating mean, median, and SUVmax range. The study was approved by the Local Bioethics Committee of the "Astana Medical University" NJSC (Decision No. 11 dated 27.02.2026).
Results: The mean age of patients was 58.5 years (range 17–87 years); 171 (55.0%) were women and 140 (45.0%) were men. Adenocarcinoma predominated (87%), predominantly G2; the majority of patients had stage II–III disease. Metastases were detected in 31.2% of patients, most frequently in the liver and lymph nodes; recurrence was observed in 13.0%. Additional suspicious lesions requiring verification were identified in 40% of patients. The mean SUVmax of metastatic lesions was 6.46 (range 1.1–13.8), for recurrence – 5.78 (range 2.6–9.5), and for suspicious lesions – 4.02.
Conclusions: PET/CT using 68Ga-FAPI is a promising imaging modality for colorectal cancer, allowing detection of metastatic and additional suspicious lesions and assessment of dynamic changes during antitumor treatment.