背景:胃蛋白酶原C(PGC)在主细胞中表达,胃底粘液颈细胞,胃上皮和乳腺的幽门腺细胞,前列腺,肺,和精囊。
方法:我们通过病理学和生物信息学分析探讨了PGCmRNA的临床病理和预后意义。我们产生了PGC敲除和PGC-cre转基因小鼠,以观察PGC阳性细胞中PGC缺失和PTEN废除对胃癌发生的影响。最后,我们通过CCK8,膜联蛋白V染色观察了PGC表达改变对侵袭性表型的影响,伤口愈合和transwell测定,并使用共IP(共免疫沉淀)和双重荧光染色分析了PGC的伴侣蛋白。
结果:PGCmRNA水平与胃癌的T和G分期以及短生存期呈负相关(p<0.05)。PGC蛋白表达与淋巴结转移呈负相关,去分化,胃癌组织中Her-2低表达(p<0.05)。野生型(WT)和PGC基因敲除(KO)小鼠体重或身长无明显差异(p>0.05),但PGCKO小鼠的存活时间比WT小鼠短(p<0.05)。在PGCKO小鼠的颗粒状胃粘膜中未观察到胃部病变,与MNU治疗后的WT小鼠相比,胃病变的频率和严重程度较低。转基因PGC-cre小鼠在肺中显示出高的cre表达和活性,胃,肾,和乳房。在两次怀孕和母乳喂养的PGC-cre/PTENf/f小鼠中发现了胃癌和三阴性小叶乳腺癌,但是在暴露于雌激素或孕激素的转基因小鼠中没有发现乳腺癌,或两次怀孕且没有母乳喂养的人。PGC抑制增殖,迁移,入侵,诱导细胞凋亡,并与CCNT1、CNDP2和CTSB相互作用。
结论:PGC下调见于胃癌,但是PGC缺失导致对化学诱导的胃癌发生产生抗性。PGC表达可能通过与CCNT1,CNDP2和CTSB相互作用抑制胃癌细胞的增殖和侵袭。在PGC-cre/PTENF/f小鼠中可见自发性三阴性小叶腺癌和胃癌,乳腺癌的发生与怀孕和母乳喂养密切相关,但不是单一暴露于雌激素或孕激素,或怀孕。限制妊娠或母乳喂养可能有助于预防遗传性乳腺癌。
BACKGROUND: Pepsinogen C (PGC) is expressed in chief cells, fundic mucous neck cells, and pyloric gland cells of gastric epithelium and also in breast, prostate, lung, and seminal vesicles.
METHODS: We explored the clinicopathological and prognostic significances of PGC mRNA using pathological and bioinformatics analyses. We generated PGC knockout and PGC-cre transgenic mice to observe the effects of PGC deletion and
PTEN abrogation in PGC-positive cells on gastric carcinogenesis. Finally, we observed the effects of altered PGC expression on aggressive phenotypes by CCK8, Annexin V staining, wound healing and transwell assays and analyzed the partner proteins of PGC using co-IP (co-immunoprecipitation) and double fluorescence staining.
RESULTS: PGC mRNA level was inversely correlated with the T and G stage and a short survival of gastric cancer (p < 0.05). PGC protein expression was negatively linked to lymph node metastasis, dedifferentiation, and low Her-2 expression of gastric cancer (p < 0.05). No difference in body weight or length was evident between wild-type (WT) and PGC knockout (KO) mice (p > 0.05), but PGC KO mice had a shorter survival than WT mice (p < 0.05). No gastric lesions were observed in the mucosa of the granular stomach in PGC KO mice, which displayed lower frequency and severity of gastric lesion than in WT mice after treated with MNU. Transgenic PGC-cre mice showed high cre expression and activity in the lung, stomach, kidney, and breast. Gastric cancer and triple-negative lobular breast adenocarcinoma were found in PGC-cre/PTENf/f mice with two previous pregnancies and breast feeding, but breast cancer was not seen in transgenic mice exposed to either estrogen or progesterone, or those with two previous pregnancies and no breast feeding. PGC suppressed proliferation, migration, invasion, and induced apoptosis, and interacted with CCNT1, CNDP2 and CTSB.
CONCLUSIONS: PGC downregulation was seen in gastric cancer, but PGC deletion resulted in resistance to chemically-induced gastric carcinogenesis. PGC expression suppressed the proliferation and invasion of gastric cancer cells possibly by interacting with CCNT1, CNDP2 and CTSB. Spontaneous triple-negative lobular adenocarcinoma and gastric cancer were seen in PGC-cre/PTENf/f mice, and the breast carcinogenesis was closely linked to pregnancy and breast feeding, but not to single exposure to estrogen or progesterone, or pregnancy. Limiting either pregnancy or breast feeding might help to prevent hereditary breast cancer.