An evaluation of the effects of medium pH on the viability of the HepG2 cell line

Yıl 2020, , 107 - 114, 31.12.2020

Neşe Güvenalp , Dilek Güvenç

https://doi.org/10.35864/evmd.742482

Cited By: 1

Öz

Cancer cells are characterized by increased glucose uptake and the production of lactate, which leads to acidification of the tumor microenvironment. This acidification facilitates the development of invasiveness and metastasis. In this study, we investigated the effects of medium pH manipulation on the proliferation and viability of human hepatocellular carcinoma (HepG2) cells in vitro. HepG2 cells were grown in media with pH ranging from 6.0 to 8.5 for 24 h. The cells were then subjected to WST-1 and trypan blue exclusion assays to evaluate viability and cell proliferation, respectively. At pH 6.8 and 6.6, HepG2 cell viability was not significantly different from the control group (pH 7.2) (p>0.05) but there was a significant decrease at pH 6.4, 6.2 and 6.0 (p < 0.05). Furthermore, there was a significant decrease in cell viability at pH’s 7.8, 8.0 and 8.5 (p<0.05). Cell numbers decreased at pH 6.8 and increased at pH 6.6, although not significantly (p>0.05), and decreased at pH 7.6 and 7.8 (significant at pH 7.8; p<0.05). In acidic environments, the cells were spindle-shaped and formed islands but they became more spherical and had reduced adhesion capacity in alkaline media. In this study, an alkaline environment reduced the proliferation and viability of the cell line, HepG2. Therefore, after further investigations, in addition to current treatments, systemic alkalization that appropriately increases the pH of the tumor microenvironment may suppress the activity of tumor cells and increase the efficacy of normal HCC treatment.

Anahtar Kelimeler

Alkali medium, HepG2, microenvironment, proliferation, Warburg effect

Destekleyen Kurum

Ondokuz Mayis University Research Foundation

Proje Numarası

PYO.VET.1904.19.001

Teşekkür

The authors thank Dr. Gregory T. Sullivan for proofreading an earlier version of this manuscript.

HepG2 hücre hattının canlılığı üzerine medium pH'sının etkisinin incelenmesi

Öz

Kanser hücreleri, tümör mikroçevresinin asitleşmesine neden olan artmış glikoz alımı ve laktat üretimi ile karakterizedir. Asidik mikro-çevre kanser hücrelerinin invazyon ve metastaz gelişimini kolaylaştırır. Bu çalışmada medium pH değişiminin, in vitro insan hepatoselüler karsinom (HepG2) hücrelerinin proliferasyon ve canlılığına etkisinin değerlendirilmesi amaçlanmıştır. HepG2 hücreleri pH değeri 6.0 ila 8.5 arasında değişen medium ortamlarında 24 saat boyunca inkübe edildi. Daha sonra hücre canlılığı ve proliferasyon değerlendirmeleri için sırasıyla WST-1 ve tripan mavisi hücre canlılık testleri uygulandı. HepG2 hücre canlılığında, medium pH’sı 6.6 ve 6.8 olan gruplar ile kontrol grubu (pH 7.2) karşılaştırıldığında önemli bir farkın bulunmadığı (p> 0.05), ancak pH 6.4, 6.2, 6.0'da önemli oranda azalmanın olduğu saptandı (p <0.05). Ayrıca alkali gruplardan pH 7.8, pH 8.0 ve pH 8.5'te hücre canlılık oranında belirgin bir azalma gözlemlendi (p<0.05). Hücre sayısında pH 6.8'de artış ve pH 6.6'da azalmanın olduğu ancak istatistiksel olarak önemli fark olmadığı (p>0.05), pH 7.6 ve 7.8'de azalmanın bulunduğu ve bu azalmanın pH 7.8’de önemli olduğu saptandı (p<0.05). Asidik ortamlarda, iğ şeklindeki hücrelerin adalar oluşturduğu, alkali ortamda ise yapışma kapasiteleri azalmış hücrelerin yuvarlak şekilde olduğu gözlendi. Bu çalışmada, alkali mikro-çevrenin HepG2 hücre hattının canlılığını ve proliferasyonunu azalttığı tespit edilmiştir. Bu nedenle, daha ileri araştırmalardan sonra mevcut tedavi yöntemlerine ek olarak tümör mikro-çevre pH'sını uygun bir şekilde yükselten sistemik alkalizasyonun, tümör hücrelerinin aktivitesini baskılayabileceği ve normal HCC tedavisinin etkinliğini artırabileceği sonucuna varıldı.

Anahtar Kelimeler

Alkali ortam, HepG2, mikro-çevre, proliferasyon, Warburg etkisi

Proje Numarası

PYO.VET.1904.19.001

Kaynakça

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