68Ga-Pentixafor PET/CT Demonstrating In Vivo CXCR4 Receptor Overexpression in Rare Lung Malignancies: Correlation with Histologic and Histochemical Findings.

68Ga-pentixafor PET/CT imaging allows noninvasive assessment of C-X-C chemokine receptor type 4 (CXCR4) expression in various malignancies, but its use in rare lung cancer variants has not been reported. Methods: 68Ga-pentixafor PET/CT imaging was performed on 6 patients (3 men, 3 women; mean age, 57.0 ± 16.8 y) with suspected lung masses. Whole-body PET/CT images were acquired 1 h after intravenous injection of 148.0-185.0 MBq of the tracer. PET/CT images were reconstructed and analyzed. The image findings were correlated with histopathologic and quantitative (CXCR4) fluorescence-activated cell sorting analysis. Results: Histopathologic diagnosis of hemangioendothelioma, sarcomatoid carcinoma, and hemangiopericytoma was confirmed in 1 patient each. Lung metastasis was diagnosed in the remaining 3 of 6 patients with primary sarcoma (n = 1), renal cell carcinoma (n = 1), and unknown primary (n = 1). Increased uptake in the primary lung mass, with an SUVmax of 3.0, 6.34, and 13.0, was noted in the hemangiopericytoma, sarcomatoid carcinoma and hemangioendothelioma cases, respectively. The mean SUVmax, mean fluorescence intensity, and percentage of stained cells were highest in hemangioendothelioma. Among 3 patients with lung metastases, the highest SUVmax, 9.5, was in the primary sarcoma patient. Conclusion: 68Ga-pentixafor selectively targets the in vivo whole-body disease burden of CXCR4 receptors. This approach thus holds promise for developing suitable radiotheranostics for lung cancers expressing these targets.

Human umbilical cord-derived mesenchymal stem cells induce tissue repair and regeneration in collagen-induced arthritis in rats.

The immunosuppressive and anti-inflammatory properties of mesenchymal stem/stromal cells (MSCs) have prompted their therapeutic application in several autoimmune diseases, including rheumatoid arthritis (RA). MSCs derived from bone marrow and adipose tissue has earlier been tried with limited success. However, Wharton's jelly present in human umbilical cord is discarded after delivery which makes a rich source of MSCs with least ethical issues. The immunomodulatory properties of human umbilical cord-derived MSCs (UC-MSCs) were evaluated in-vitro on the mononuclear cells from synovial fluid (SF) and peripheral blood of RA patients. The therapeutic potential of UC-MSCs was checked by transplanting the cells in rats with collagen-induced arthritis (CIA). MSCs isolated from Wharton's Jelly significantly suppressed the proliferation and activation of lymphocytes from both peripheral blood as well as SF of RA patients, down-modulated the functions of activated CD4+, CD8+ T-cells, suppressed the secretion of pro-inflammatory cytokines, and induced the expansion of T-regulatory cells. Xenotransplantation of UC-MSCs in CIA rats clearly indicated a sustained impact in terms of slowing down the progression of disease activity and reversal of arthritic processes along with triggering of joint tissue repair mechanisms, which could be observed till 6 weeks post-transplantation. The results from the current study suggest that human umbilical cord is a rich source of MSCs for allotransplantation. The UC-MSCs may be used successfully as a cell-based therapeutic option either in isolation or in conjunction with existing therapeutic drugs not only to relieve the joint inflammation but also regenerate the damaged bone and cartilage tissues in arthritis. RELEVANCE TO PATIENTS: The current study highlights the potential use of MSCs as a cell-based therapeutic option for the treatment of inflammatory RA.