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beta-Catenin and gamma-catenin (plakoglobin), vertebrate homologs of Drosophila armadillo, function in cell adhesion and the Wnt signaling pathway. In colon and other cancers, mutations in the APC tumor suppressor protein or beta-catenin's amino terminus stabilize beta-catenin, enhancing its ability to activate transcription of Tcf/Lef target genes. Though beta- and gamma-catenin have analogous structures and functions and like binding to APC, evidence that gamma-catenin has an important role in cancer has been lacking. We report here that APC regulates both beta- and gamma-catenin and gamma-catenin functions as an oncogene. In contrast to beta-catenin, for which only amino-terminal mutated forms transform RK3E epithelial cells, wild-type and several amino-terminal mutated forms of gamma-catenin had similar transforming activity. gamma-Catenin's transforming activity, like beta-catenin's, was dependent on Tcf/Lef function. However, in contrast to beta-catenin, gamma-catenin strongly activated c-Myc expression and c-Myc function was crucial for gamma-catenin transformation. Our findings suggest APC mutations alter regulation of both beta- and gamma-catenin, perhaps explaining why the frequency of APC mutations in colon cancer far exceeds that of beta-catenin mutations. Elevated c-Myc expression in cancers with APC defects may be due to altered regulation of both beta- and gamma-catenin. Furthermore, the data imply beta- and gamma-catenin may have distinct roles in Wnt signaling and cancer via differential effects on downstream target genes.

This article discusses the issue of international technology licensing. Along with the issue of appropriateness of technology, the compensation issue has been major concerns of licensors, licensees and licensee governments. In imperfect international technology markets, technology prices tend to be determined as a result of a series of negotiations between licensors and licensees and are strongly influenced by their relative bargaining leverages in the negotiation process. Particularly, imperfect nature of international technology markets and weak bargaining leverages of licensees frequently lead to charges of over-compensation for the technologies purchased by licensees and their governments, and provide reasons for their governments to intervene in international technology licensing to ensure fair prices, though elusive, for the technologies imported. Some policy implications can be made from the above discussions with regard to the issue of fair compensation in international technology licensing. Generally, licensee government policies on technology compensation are aimed at lowering short-run balance-of-payments costs by enacting ceilings on size and rates of royalty and other fees or prohibiting inequitable compensatory provisions of licensing agreements.

Countertrade has become a reality and is increasing in prominence in international business scene today. Despite its negative macroeconomic welfare and efficiency implications, its shrewd employment can be an effective management technique in increasingly competitive international markets. It can provide important opportunities to enter new foreign markets, expand foreign sales, procure necessary raw materials or intermediate products on favorable terms, and help operate production facilities optimally. This article explores various advantages and pitfalls of countertrade and suggests the need for a corporatewide concerted approach to properly use it as a competitive management tool. The complexity and uniqueness of countertrade management requires wider participation of and closer coordination among various functions of the company. A belief that countertrade can be effectively handled within the capacity of normal trading function would prove to be very costly for the company involved. Considering the resurgence and pervasiveness of countertrade and the increasing market competition in recent international business scene, a shrewd use of countertrade can be an important management technique for a company to obtain a competitive advantage in international markets. Clear understanding of various advantages and pitfalls of the countertrade and a concerted managerial approach mobilizing existing company resources would make this possible.

The article discusses determinants of multinational banks (MNBs). A theoretical model has been developed by the author to explain the phenomenon of multi-national banks (MNBs). Several factors have been identified, which are instrumental for the growth of MNBs. Size of a bank, effective lending rate differentials and size of host banking market are found to be important determinants of MNB growth in the onshore market, whereas size of a bank is found to be an important determinant in the offshore market. No internalization advantage factors are found to be significant in this particular set of tests. One alternative explanation for this may be any internalization advantage effects that actually exist might have been subsumed under effects of ownership-specific advantages as quite frequently only "internalized" ownership-specific advantages are reflected in ex post bank performance data used in most empirical studies. If this is true, more powerful proxies for internalization advantage factors might have been able to separate internalization advantage effects from ownership-specific advantage effects. But the current level of bank data availability makes this extremely difficult to accomplish. This fact remains to be the most controversial aspect of the eclectic model in explaining MNBs empirically.