Anticancer activity of carbon dots with different chemical compositions against Lewis lung carcinoma in mice

This study investigated the antitumor potential of carbon dots (CDs) with distinct surface chemistries in a Lewis lung carcinoma (LLC) mouse model. The effects of CD_3011, CDN19, and CDF19 were evaluated in terms of tumor growth, systemic biochemical and hematological responses, and histopathological changes. All tested formulations produced measurable tumor growth inhibition, with statistically significant effects emerging between days 12 and 14 of treatment. Relative tumor volume analysis demonstrated significant inhibition for CDN19 and CDF19, whereas CD_3011 showed a non-significant trend, likely due to higher variability. Tumor growth inhibition indices confirmed CDN19 as the most potent formulation, also showing significant suppression of metastasis. Vehicle-treated tumor-bearing mice exhibited elevated AST, GGT, and LDH levels, decreased ALP and urea, leukocyte redistribution (reduced lymphocytes, increased granulocytes), and reduced erythrocyte counts. CD treatment partially normalized these tumor-associated systemic alterations, with most parameters remaining within physiological ranges. Histologically, Vehicle-treated animals displayed renal stress, hepatic micrometastases, inflammatory infiltration, and high tumor proliferation with limited apoptosis. CD administration attenuated liver metastasis, reduced inflammatory and vascular changes, suppressed tumor proliferation, and enhanced apoptosis and necrosis, particularly in the CDN19 group. Mild renal alterations were noted in some CD-treated groups, consistent with prior toxicity observations. Overall, the findings demonstrate that surface-modified carbon dots—especially CDN19—exert antitumor, anti-metastatic, and systemic protective effects, supporting their potential as multifunctional nanotherapeutic agents in cancer treatment.