Interaction between CXCR4 and CCL20 Pathways Regulates Tumor Growth

The chemokine receptor CXCR4 and its ligand CXCL12 is overexpressed in the majority of tumors and is critically involved in the development and metastasis of these tumors. CXCR4 is expressed in malignant tumor cells whereas its ligand SDF-1 (CXCL12) is expressed mainly by cancer associated fibroblasts (CAF). Similarly to CXCR4, the chemokine CCL20 is overexpressed in variety of tumors; however its role and regulation in tumors is not fully clear. Here, we show that the chemokine receptor CXCR4 stimulates the production of the chemokine CCL20 and that CCL20 stimulates the proliferation and adhesion to collagen of various tumor cells. Furthermore, overexpression of CCL20 in tumor cells promotes growth and adhesion in vitro and increased tumor growth and invasiveness in vivo. Moreover, neutralizing antibodies to CCL20 inhibit the in vivo growth of tumors that either overexpress CXCR4 or CCL20 or naturally express CCL20. These results reveal a role for CCL20 in CXCR4-dependent and -independent tumor growth and suggest a therapeutic potential for CCL20 and CCR6 antagonists in the treatment of CXCR4- and CCL20-dependent malignancies

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Application of geomorphic principles to environmental management in semiarid regions

Submitted to Office of Water Research and Technology, U.S. Department of the Interior.Bibliography: p.42-43.February 1980.The incision of gullies into valley alluvium is a severe soil conservation problem, resulting in deterioration of agricultural land, sediment pollution, filling of reservoirs, and water table lowering in the valley floor. Therefore, it is of importance to identify as accurately as possible those valleys which are prone to gullying, in order to establish priorities for soil conservation treatment within a geomorphically similar area. In other words, what is needed is an operational definition of the geomorphic threshold above which gully incision into the valley alluvium occurs. In many valleys of the semiarid west valley floors are either flat and vegetated without a channel, or they are gullied. It will be of value to establish under what conditions the stable valley floor is incised by discontinuous gullies. Normally the explanation is a large storm, overgrazing or other man-induced changes; however, the character of the valley floor also plays an important role. The valley floor itself can provide a means of recognizing incipiently unstable conditions that lead to incision. Using previously collected data from the Piceance Creek area of western Colorado, it is possible to identify a valley-slope threshold above which, for a given drainage area, gullying is certain. Below this valley-slope threshold the valley floors are stable; above it they are susceptible to gullying. When the relations and techniques developed in western Colorado were applied to a similar situation in northeastern Colorado, the Chalk Bluffs area, it was determined that valley width was also a significant factor determining valley stability, and a ratio of valley slope to valley width could be used to identify at a given drainage area a threshold zone of valley floor instability. These relations explain the observed variability of gullies and also permit identification of those locations where gullying is probable.OWRT Project no. B-150-COLO; supported (in part) by funds provided by the U. S. Department of the Interior, Office of Water Research and Technology, as authorized by the Water Resources Research Act of 1978, and pursuant to Grant Agreement no. 14-34-001-7143