e15056 Background: Precision radiotherapy has improved dose delivery, but biological response assessment is delayed, especially in high-volume Indian settings where early recognition of radio-resistance could alter outcomes. Circulating free DNA (cfDNA) reflects dynamic tumor burden and may offer a real-time biomarker. We assessed cfDNA kinetics during precision radiotherapy to predict response across diverse solid tumors. Methods: In this prospective, single-centre study we enrolled 22 adults undergoing image-guided radiotherapy for lung, esophageal, cervical, gastric or breast cancers. Peripheral blood was drawn at baseline, mid-course and completion. cfDNA was isolated from plasma via standardized EDTA-centrifugation protocol and quantified fluorometrically. Changes were calculated relative to baseline. End-of-treatment cfDNA below baseline defined a responder; mid-course decline defined early decline. Radiologic response was evaluated at 6–8 weeks post-RT using RECIST 1.1. Results: Baseline cfDNA values were heterogeneous. During treatment, cfDNA decreased in 8 patients and increased in 14. At completion, 10 patients (45%) had cfDNA decrease and were radiologic responders, while 12 (55%) had an increase and were non-responders. Early decline identified 5 of 10 final responders and early rise identified 9 of 12 final non-responders, so the early cfDNA trend matched the final trend in 14 of 22 cases (64%). cfDNA response agreed with imaging in 19 of 22 patients (90% concordance). In the breast-cancer subset (14 patients), 7 experienced cfDNA decline by the end of therapy. Conclusions: Real-time cfDNA monitoring during precision radiotherapy is feasible and provides an early indicator of treatment response across heterogeneous Indian cancers. Early cfDNA rise predicted resistance, whereas decline correlated with radiologic response. Though limited by sample size, this study shows that cfDNA trends are simple to measure and could be integrated into weekly clinic visits to guide adaptive dosing, prompt systemic therapy initiation, and engage patients. Further multicenter studies are needed to validate thresholds, interpret dynamics, and integrate cfDNA into personalized radiation oncology.
Ralstonia solanacearum is a major bacterial pathogen that causes wilt disease, leading to yield losses of up to 90 % in solanaceous crops such tomato (Solanum lycopersicum), brinjal (S. melongena), potato (S. tuberosum), chili (Capsicum annuum). This study investigated the antibacterial potential of Solanum torvum (S. torvum) plant extracts against this pathogen. Extracts from the root, stem and fruit were evaluated for their antimicrobial activity. Gas chromatography-mass spectrometry (GC-MS) analysis of the root extract revealed several bioactive compounds, including Oxirane, Decon-1-ol, 1-Cyclo Azopropyl and Pentadecanoic acid, which confirm its antimicrobial effects. The minimum inhibitory concentrations (MIC) of the root and leaf extracts ranged from 7.5 mg/mL to 10 mg/mL, indicating strong antibacterial activity. The root extract also demonstrated a lethal time (LT50) of 6.6 hr, confirming its effectiveness against R. solanacearum. Furthermore, the extract exhibited biofilm-inhibitory activity, with an IC50 value of 37.03 mg/mL, suggesting its ability to prevent bacterial colonization and biofilm formation.
Oral squamous cell carcinoma (OSCC) imposes a disproportionate epidemiological burden in India, yet lacks validated predictive biomarkers for immune-based therapies. We characterised the tumour immune microenvironment (TME) by evaluating tumour-infiltrating lymphocyte (TIL) subsets (CD3+, CD4+, CD8+, FOXP3+ and CD57+), PD-L1 expression, HPV/p16 status and the systemic peripheral neutrophil-to-lymphocyte ratio (NLR) in resection specimens from 299 patients (stratified by disease outcome: non-recurrent, n=106; recurrent, n=193) treated at two tertiary oncology centres in Bangalore and Cuttack, India, between 2020 and 2023. TIL subsets were assessed by immunohistochemistry; PD-L1 was scored using the Dako 22C3 assay with a cut-off of …., and p16 was interpreted per College of American Pathologists guidelines. FOXP3+ regulatory T cells showed the broadest association with adverse histopathology, including lymphovascular invasion (LVI; P < 0.001), worst pattern of invasion (WPOI; P = 0.038), and lymph node metastasis (P = 0.003). PD-L1 expression correlated positively with all five TIL subsets (P < 0.001 for each), defining an “inflamed but suppressed” TME. p16-positive tumours (4.0%, associated with recurrent patients) showed markedly reduced FOXP3+ infiltration (P < 0.001). In multivariate regression, only LVI and WPOI were associated with elevated pre-treatment log-NLR. The immune microenvironment was statistically indistinguishable between non-recurrent and recurrent tumours across all immune parameters. This integrated multi-biomarker framework — combining intratumoral TIL subset profiling, PD-L1 scoring, HPV/p16 status, and systemic NLR — demonstrates practical utility for immunotherapy patient stratification in South Indian OSCC. Notably, in our study, this utility operates independently of recurrence prediction, suggesting immunotherapy eligibility is a distinct biological dimension from recurrence risk
e16081 Background: Epidemiological studies on drug therapy outcomes in specific populations are crucial for post-marketing surveillance (PMS), especially in cancer treatment due to their toxicity and ethnic/interpersonal variability in therapy response. Relative Dose Intensity (RDI), the ratio of administered to standard dose per m² BSA per week, measures chemotherapy tolerance. This study evaluates RDI of capecitabine+oxaliplatin (CAPOX) therapy and its correlation with overall survival (OS) in the genetically diverse Indian gastric cancer population. Methods: This pilot-retrospective study analysed 30 patients (18–60 years) with Stage II/III gastric cancer who underwent D2 lymph node dissection (2015–2018). Data from medical records evaluated toxicities graded per CTCAE v5.0. RDI, calculated as administered dose intensity relative to the standard (mg/m²/week), was assessed. OS, the primary endpoint, measured survival from CAPOX initiation to death. Kaplan–Meier analysis estimated OS, with log-rank tests evaluated age, gender, stage, and mean RDI against median OS (P < 0.05). SPSS 23 was used for descriptive and survival analysis. Results: The mean follow-up was 5 years, with a median OS of 29.8 ± 11.5 months. The mean RDI of Capecitabine (54.30% ± 14.8) was notably lower than Oxaliplatin (85.60% ± 21.9). Half the patients (n = 15) failed to complete 6 cycles, among them 60% (n = 9) received below-mean RDI due to intolerance. Patients with Capecitabine RDI < 54.30% had significantly higher OS (37.61 ± 9.80 months, p = 0.005) than those > 54.30% (8.58 ± 2.18 months). Similarly, Oxaliplatin RDI < 85.6% reported 37.61 ± 8.28 months OS, compared to 10.95 ± 2.57 months > 85.6% (p = 0.005). Survival differences by age or stage were insignificant. Toxicities included fatigue (n = 6), neuropathy (n = 4), and hand-foot syndrome (n = 3). Conclusions: Our study reveals that reduced RDI for Capecitabine and Oxaliplatin, compared to standard CAPOX dosing, improved overall survival in Stage II/III gastric cancer patients within the Indian population. As a pilot study, these findings emphasize the need for larger studies to explore dose modifications for safe and effective drug therapy in specific population and highlights RDI’s value as a marker in region-specific post-marketing surveillance. Characteristics versus median survival. Parameters 95%CI (Range) N (%) Median Survival ± SD(months) 95%CI (Range) P value Age (mean ± SD) 65 ±9.75 43-78 >60 yrs 16 43.8 35.1±15.6 0.23 <60 yrs 8 25 29.9±8.2 Tumour stage Stage 2 10 33.3 29.9±12.6 0.58 Stage 3 13 43.3 20.5±12.6 Capecitabine RDI(mean ± SD) 54.30±14.8 18.39-56.83 RDI<54.3% 12 40 37.6±9.8 18.4-56.8 0.005 RDI>54.3% 12 40 8.6±2.2 4.5–12.9 Oxaliplatin RDI (mean ± SD) 85.60±21.9 37.6-133.5 <85.6% 11 36.6 37.6±8.3 21.4-53.9 0.005 >85.6% 13 43.3 10.9±2.6 5.9–16 Note: 6 patients were omitted due to lack of follow up.
