Recent advances in biomaterials and 3D printing/culture methods enable various tissue-engineered tumor models. However, it is still challenging to achieve native tumor-like characteristics due to lower cell density than native tissues and prolonged culture duration for maturation. Here, we report a new method to create tumoroids with a mechanically active tumor-stroma interface at extremely high cell density. This method, named “inkjet-printed morphogenesis” (iPM) of the tumor-stroma interface, is based on a hypothesis that cellular contractile force can significantly remodel the cell-laden polymer matrix to form densely-packed tissue-like constructs. Thus, differential cell-derived compaction of tumor cells and cancer-associated fibroblasts (CAFs) can be used to build a mechanically active tumor-stroma interface. In this methods, two kinds of bioinks are prepared, in which tumor cells and CAFs are suspended respectively in the mixture of collagen and poly (N-isopropyl acrylamide-co-methyl methacrylate) solution. These two cellular inks are inkjet-printed in multi-line or multi-layer patterns. As a result of cell-derived compaction, the resulting structure forms tumoroids with mechanically active tumor-stroma interface at extremely high cell density. We further test our working hypothesis that the morphogenesis can be controlled by manipulating the force balance between cellular contractile force and matrix stiffness. Furthermore, this new concept of “morphogenetic printing” is demonstrated to create more complex structures beyond current 3D bioprinting techniques.

生物材料和 3D 打印/培养方法的最新进展使各种组织工程肿瘤模型成为可能。然而，由于细胞密度低于天然组织且培养成熟时间较长，实现天然肿瘤样特征仍然具有挑战性。在这里，我们报告了一种以极高的细胞密度创建具有机械活性肿瘤基质界面的类肿瘤的新方法。这种方法被称为肿瘤-基质界面的“喷墨打印形态发生”（iPM），基于这样的假设：细胞收缩力可以显着重塑充满细胞的聚合物基质，形成致密的组织样结构。因此，肿瘤细胞和癌症相关成纤维细胞（CAF）的细胞衍生压实差异可用于构建机械活性的肿瘤基质界面。在该方法中，制备了两种生物墨水，其中肿瘤细胞和CAF分别悬浮在胶原蛋白和聚(N-异丙基丙烯酰胺-共-甲基丙烯酸甲酯)溶液的混合物中。这两种细胞墨水以多线或多层图案喷墨印刷。由于细胞源性压实，所得结构以极高的细胞密度形成具有机械活性肿瘤-基质界面的肿瘤样体。我们进一步测试了我们的工作假设，即形态发生可以通过操纵细胞收缩力和基质刚度之间的力平衡来控制。此外，这种“形态发生打印”的新概念被证明可以创造出超越当前 3D 生物打印技术的更复杂的结构。