In vivo and in vitro application of near-infrared fiber optic probe for Ehrlich carcinoma distinction: Towards the development of real-time tumor margins assessment tool.

This report describes a full-scale experiment on intradermal Ehrlich carcinoma (EC) differentiation in mouse model using NIR spectroscopy in diffuse reflectance mode and chemometric data processing. EC is widely used as an experimental tumor model due to its resemblance with human undifferentiated epithelial tumors and can be applied as a preclinical testing in order to verify the capability of NIR spectroscopy to distinguish cancer from healthy tissues before a clinical research with an aim of creating a new analytical tool for on-line intraoperative tumor margins assessment. The study consists of five steps of NIR spectra measurements: in vivo on the early stage of carcinoma growth; in vivo on the advanced stage of carcinoma growth; in vivo during the surgery; in vitro study of the post-operative materials stored in formalin; in vitro study of the post-operative materials stored in paraffin. It was shown that reliable tumor differentiation with a compact optic fiber probe was possible in all these cases. The classification models were built on two data sets, obtained during in vivo and in vitro measurements; both of them demonstrated 100% specificity and sensitivity.

Licorice preparations improve efficiency of chemotherapy and surgical treatment of transplanted tumors.

Experiments on animals with Lewis lung carcinoma and Ehrlich tumor showed that licorice (glycyrrhiza) extract and glyciram prepared from this plant improved the antitumor effect of cyclophosphamide. Glyciram reduced the toxic effect of the cytostatic on peripheral blood leukocytes. Licorice extract inhibited the growth of Ehrlich tumor and development of metastases in mice with Lewis lung carcinoma. Glyciram administered to mice after removal of Lewis lung carcinoma produced an antimetastatic effect and prevented relapses.

Specificity of relapses and metastases of experimental transplanted Ehrlich carcinoma and B16 melanoma.

Experiments on female (CBAxC57Bl/6)F1 mice with simultaneously transplanted Ehrlich carcinoma and B16 melanoma showed that removal of one of the primary nodes led to metastasizing of the removed tumor alone. It seems that this specificity of the inhibitory effect of the primary tumor can be explained by peculiarities of glycosylation and subsequent complex formation of serum proteins with the tumor.

Low dose gamma-rays activate immune functions via induction of glutathione and delay tumor growth.

We examined whether the increase of glutathione level induced by low dose gamma-ray irradiation is involved in the appearance of enhanced natural killer (NK) activity and antibody-dependent cellular cytotoxicity (ADCC), leading to delayed tumor growth in Ehrlich solid tumor-bearing mice. NK activity in ICR mouse splenocytes significantly increased from 4 h to 6 h after whole-body gamma-ray irradiation at 0.5 Gy, and thereafter decreased almost to the zero-time level by 24 h post-irradiation. ADCC also increased significantly in a similar way. Reduced glutathione exogenously added to splenocytes obtained from normal mice enhanced both NK activity and ADCC in a dose-dependent manner. Since immune functions were enhanced through the induction of cellular glutathione after low-dose irradiation, the inhibitory effect of the radiation on tumor growth was then examined in Ehrlich solid tumor-bearing mice. Tumor growth after inoculation was significantly delayed by the radiation. These results suggest that low-dose gamma-rays activate immune functions via an induction of glutathione, leading to a delay of tumor growth.

Effect of a submaxillary gland extract on Ehrlich tumor growth in mice

Ablation of host submaxillary glands modifies Ehrlich tumor growth and tumor-infiltrating leukocytes, possibly by modifications in the serum level of growth factors produced by this gland. To extend this research, 7-month-old male EPM-1 mice (N = 30) were divided into two groups: 1) inoculated with tumor cells previously incubated with submaxillary salivary gland extract (SGE) in PBS for 30 min at 37 percent; 2) inoculated with tumor cells previously incubated with PBS, under the same conditions. Animals were inoculated into the footpad with 40 µl of a suspension containing 4.5 x 107 tumor cells/ml, and footpad thickness was measured daily for 10 days. Sections and smears of tumor cells were prepared from the tumor mass to determine mitosis frequency, percent of tumor cells immunopositive to nerve (NGF) and epidermal (EGF) growth factors and percent of tumor-infiltrating leukocytes. The incubation of tumor cells with SGE produced a tumor reduction of about 30 percent in size. This effect was not related to loss of cell viability during incubation, but a 33 percent increase 0.05 in the percentage of dead or dying tumor cells and a 15 percent increase in the percent of NGF/EGF-positive tumor cells 0.01 were observed in vivo at the end of experiment. Tumor-infiltrating lymphocytes and mitosis frequency did not differ between groups. These data suggest a direct effect of factors present in SGE on tumor cells, which induce degeneration of tumor cells

[The characteristics of Ehrlich carcinoma recurrence and metastasis]. / Nekotorye osobennosti retsidivirovaniia i metastazirovaniia kartsinomy Erlikha.

It was shown that surgical removal of Ehrlich carcinoma growing i. m. in male mice F1 (CBA C57Bl/6) does not entail longer survival in comparison with intact tumor-bearing mice (59.4 and 62.2 days, respectively). Postoperative relapses appear in 40-60% of the animals, metastases in 100% of animals. Metastases were not observed in intact tumor bearing mice. The second-challenge tumor was not observed in operated mice despite metastatic growth and recurrences of the same tumor. We suggest that metastatic growth depends on the tumor cell features and that this process is controlled by host organism.

[The effect of antitumor vaccine on the recurrence of solid tumors in mice subjected to surgery]. / Vliianie protivoopukholevoi vaktsiny na retsidivirovanie solidnykh novoobrazovanii u prooperirovannykh myshei.

The frequency of tumour recurrences in A/Sn mice with operated Ehrlich carcinomas and treated with lyophylized antitumour vaccine and trypan blue or both of them was investigated. The tumours in vaccinated mice relapsed by the 47th day after the operation in 10% of cases, in 50% of control animals, the injection of trypan blue increased the tumour recurrences by 20%. The antitumour effect of vaccination is associated with the enhancement of the activity of the cellular and humoral immune systems. The trypan blue inhibition of the macrophage function suppresses the antitumor activity of the immunity cellular components.

Augmentation of antitumor activity by combined cryo-destruction of sarcoma 180 and protein-bound polysaccharide, EA6, isolated from Flammulina velutipes (Curt. ex Fr.) Sing. in ICR mice.

Augmentation of antitumor activity by combined in situ freeze-destruction of tumor (cryosurgery) and administration of antitumor active substances isolated from a hot water extract of an edible mushroom, Flammulina velutipes (Curt. ex Fr.) SING., was investigated in sarcoma 180 bearing ICR mice. Antitumor active substances of the mushroom included beta-(1,3)-glucan (EA3) and protein-bound polysaccharide (EA6). Antitumor activity was evaluated by the growth rate of the solid tumor rechallenged subcutaneously (s.c.) or by cumulative mortalities of the mice rechallenged intraperitoneally (i.p.) with the ascites tumor, on day 7 after cryosurgery. Weak antitumor effect induced by cryosurgery against challenged solid tumor of sarcoma 180 was markedly augmented by i.p. administration of EA6 (10 mg/kg). Cryosurgery of the solid sarcoma 180 apparently did not induce any antitumor effect against challenged ascites sarcoma 180. However, when cryosurgery was combined with oral administration of the polysaccharides (50 mg/kg), prolonged survival of the mice challenged with ascites sarcoma 180 i.p. was recognized by EA6, but not by EA3. Timing of the administration of EA6 (i.p.) with cryosurgery was best in pre- and post-cryosurgery. Immunological activity of EA6 to the host was discussed.

[Effect of pulsed laser radiation on the lysosomes of Ehrlich ascitic tumor cells]. / Vliianie impul'snogo lazzernogo izlucheniia na lizosomy kletok astsitnoi opukholi Erlikha.

The results of a study on the effect of neodymium pulsed laser radiation on Ehrlich ascites tumor lysosomes are discussed. Tumor cell suspension was exposed in vitro to 10 pulses of laser irradiation with fluences of 10, 25 and 100 J/cm2, at a wavelength of 1.06 microns and a pulse duration of 1 microsecond. A rise in the free and total activities of acid phosphatase in the fraction of isolated lysosomes was registered one or four hours after exposure, particularly, at fluences of 10 and 25 J/cm2. However, laser radiation did not affect acid phosphatase activity in preparations of solubilized enzyme. Special experiments involving the use of detergents showed the increased activity of acid phosphatase in isolated lysosome fraction to be due to labilization of cytoplasmic membranes of tumor cells.

[Kinetic changes in the cellular proliferation of Ehrlich ascites tumor as affected by low-intensity laser radiation]. / Izmenenie kinetiki kletochnoi proliferatsii astsitnoi opukholi Erlikha pod vliianiem lazernogo izlucheniia maloi moshchnosti.

A radiographical study, using 3H-thymidine, has shown that, under the influence of He-Ne laser irradiation, the enhancement of the Ehrlich ascite tumour growth is associated with a shorter duration of the mitotic cycle which, in turn, is due to the decrease of all its phases. Besides, the enhancement is related to the increase of proliferative pool.